Novell Security Manager Powered by Astaro User guide

Novell Confidential Manual (ENU) 21 December 2004

Novell

Security Manager Powered by

Astaro

w w w . n o v e l l . c o m

U S E R G U I D E

F e b r u a r y 2 5 , 2 0 0 5


Legal Notices

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Further, Novell, Inc. makes no representations or warranties with respect to any software, and specifically disclaims any express or implied warranties of merchantability or fitness for any particular purpose. Further, Novell, Inc. reserves the right to make changes to any and all parts of Novell software, at any time, without any obligation to notify any person or entity of such changes.

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Novell, Inc.

404 Wyman Street, Suite 500

Waltham, MA 02451

U.S.A.

www.novell.com

Novell Security Manager Powered by Astaro User Guide

February 25, 2005

Online Documentation: To access the online documentation for this and other Novell products, and to get updates, see www.novell.com/documentation.


Novell Trademarks

NetWare is a registered trademark of Novell, Inc. in the United States and other countries.

Novell is a registered trademark of Novell, Inc. in the United States and other countries.

SUSE is a registered trademark of SUSE LINUX AG, a Novell business.

Third-Party Materials

Astaro Security Linux and WebAdmin are trademarks of Astaro AG. Linux is a trademark of Linus Torvalds. All third-party trademarks are the property of their respective owners.

Portions © Astaro AG. All rights reserved. Pfinztalstrasse 90, 76227 Karlsruhe, Germany (http://www.astaro.com). Portions © Kaspersky Labs.


Table of Contents

Contents Page

1.Introduction to the Technology.............................................5

2.Installation.........................................................................12

2.1.System Requirements .....................................................13

2.2.Installation Instructions .................................................16

2.2.1.Software Installation ...................................................16

2.2.2.Configuring the Security System ..................................21

3.WebAdmin .........................................................................29

3.1.Info Box .........................................................................30

3.2.Tab List ...........................................................................30

3.3.Menus 31

3.3.1.The Status Light ...........................................................31

3.3.2.Selection Field ..............................................................31

3.3.3.The Selection Table ......................................................32

3.3.4.Drop-down Menus ........................................................33

3.3.5.Lists 34

3.4.Online Help .....................................................................35

3.5.Refresh ...........................................................................36

4.Using the Security System .................................................37

4.1.Basic Settings (System)...................................................39

4.1.1.Settings ........................................................................39

4.1.2.Licensing .....................................................................44

4.1.3.Up2Date Service ...........................................................48

4.1.4.Backup .........................................................................55

4.1.5.SNMP ...........................................................................62

4.1.6.Remote Syslog Server ..................................................64

4.1.7.User Authentication .....................................................66

4.1.7.1.RADIUS .....................................................................67

4.1.7.2.SAM – NT/2000/XP ...................................................72

4.1.7.3.Active Directory/NT Domain Membership .................74

4.1.7.4.LDAP Server ..............................................................76

4.1.8.WebAdmin Settings ......................................................92

4.1.9.WebAdmin Site Certificate ...........................................95

4.1.10.High Availability .........................................................98

4.1.11.Shut down/Restart ...................................................105

4.2.Networks and Services (Definitions) .............................105

4.2.1.Networks ....................................................................106

4.2.2.Services .....................................................................113

4.2.3.Users ..........................................................................117

4.3.Network Settings (Network) .........................................121

4.3.1.Hostname/DynDNS ....................................................121

4.3.2.Interfaces ..................................................................122

4.3.2.1.Standard Ethernet Interface ...................................127

4.3.2.2.Additional Address on Ethernet Interface ................133

4.3.2.3.Wireless LAN ...........................................................135

4.3.2.4.Virtual LAN .............................................................145

4.3.2.5.PPPoE-DSL Connection ............................................150

4.3.2.6.PPTPoE/PPPoA-DSL Connections ............................155

4.3.2.7.PPP over Serial Modem Line ....................................160

4.3.3.Routing ......................................................................166

4.3.4.NAT/Masquerading.....................................................168

4.3.4.1.NAT .........................................................................168

4.3.4.2.Masquerading ..........................................................172

4.3.4.3.Load Balancing ........................................................173

4.3.5.DHCP Server ...............................................................176

4.3.6.PPTP VPN ...................................................................180

4.3.7.Accounting .................................................................186

4.3.8.Ping Check .................................................................188

4.4.Intrusion Protection ......................................................190

4.4.1.Settings ......................................................................190

4.4.2.Rules ..........................................................................192

4.4.3.Advanced ...................................................................197

4.5.Packet Filter ..................................................................199

4.5.1.Rules ..........................................................................199

4.5.2.ICMP ..........................................................................211

4.5.3.Advanced ...................................................................214

4.6.Application Gateways (Proxies).....................................220

4.6.1.HTTP ..........................................................................221

4.6.1.1.Content Filter (Surf Protection) ...............................229

4.6.2.DNS 241

4.6.3.SOCKS ........................................................................243

4.6.4.POP3 ..........................................................................245

4.6.5.Ident ..........................................................................250

4.6.6.SMTP ..........................................................................251

4.6.6.1.Content Filter ..........................................................260

4.6.6.2.Spam Protection ......................................................265

4.6.7.Proxy Content Manager ..............................................274

4.7.Virtual Private Networks (IPSec VPN) ...........................280

4.7.1.Connections ...............................................................288

4.7.2.Policies .......................................................................297

4.7.3.Local Keys ..................................................................301

4.7.4.Remote Keys ..............................................................304

4.7.5.L2TP over IPSec .........................................................307

4.7.6.CA Management .........................................................309

4.7.7.Advanced ...................................................................314

4.8.System Management (Reporting) ..................................317

4.8.1.Administration ...........................................................317

4.8.2.Virus ..........................................................................318

4.8.3.Hardware ...................................................................318

4.8.4.Network .....................................................................319

4.8.5.Packet Filter ...............................................................320

4.8.6.Content Filter .............................................................320

4.8.7.PPTP/IPSec VPN ........................................................321

4.8.8.Intrusion Protection ...................................................321

4.8.9.DNS 321

4.8.10.HTTP Proxy Usage ....................................................321

4.8.11.Executive Report ......................................................321

4.8.12.Accounting ...............................................................322

4.8.13.System Information .................................................324

4.9.Remote Management (Remote Management) ................326

4.9.1.Report Manager (RM) .................................................326

4.10.Local Logs (Log Files) .................................................331

4.10.1.Settings ....................................................................331

4.10.2.Local Log File Query .................................................335

4.10.3.Browse .....................................................................336

4.10.3.1.Log Files ................................................................340

4.10.3.2.Error Codes ...........................................................344

4.11.Online Help .................................................................358

4.12.Exiting the Security System ........................................359

Glossary...............................................................................360

Index...................................................................................367

Notes ..................................................................................381

Table of Contents

4

Installation

1.Introduction to the Technology

Before exploring the Novell Security Manager powered by Astaro security system in detail, it may be helpful to take an overview of network and security technology in general. In particular, it is important to understand the serious risks that unprotected systems face as well as where and how to deploy this security system to mitigate these risks.

Networks

The Internet is already well established as a vital communications medium and a key marketplace for both traditional and new services.

Since its inception, its size has multiplied, with domain name growth between 1995 and 2003 reaching almost exponential proportions.

Computers on this worldwide network communicate using the Inter-

net Protocol (IP), as well as various higher-level protocols such as

TCP, UDP, and ICMP. IP addresses uniquely identify each of the computers reachable on the network.

The Internet itself is a collection of smaller networks of various kinds.

When two or more networks are connected, a number of issues arise which are dealt with by devices such as routers, bridges, and gateways. A firewall is another such device, designed with security in mind.

As a rule, three kinds of network meet at the firewall:

• An external or Wide Area Network (WAN)

• An internal or Local Area Network (LAN)

• A De-Militarized Zone (DMZ)

An example configuration is shown on the next page.

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Installation

The Firewall

One of the components in this security system is a firewall. The characteristic tasks of a firewall connecting a WAN, LAN, and DMZ are:

• Protection against unauthorized access

• Access control

• Collection of audit trails

• Protocol analysis

• Reporting of security-related events

• Concealing internal network structure

• Separation of servers and clients using proxies

• Guaranteeing information confidentiality

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Installation

A firewall combines several network components in order to provide these assurances. The following is a brief look at some of these tools and their uses.

Network-Layer Firewalls: Packet Filters

As the name suggests, this component filters IP packets on the basis of source and destination address, IP flags, and packet payload. This allows an administrator to grant or deny access to services based on factors such as:

• The source address

• The destination address

• The protocol (e.g., TCP, UDP, ICMP)

• The port number

The primary advantages of packet filters are their speed and their independence of operating systems and applications in use behind the firewall.

Advanced implementations of packet filters also inspect packets at higher network layers. Such filters interpret transport-level information (such as TCP and UDP headers) to analyze and record all current connections. This process is known as stateful inspection.

A stateful packet filter records the status of all connections, and allows only those packets associated with a current connection to pass. This is especially important for allowing connections from a protected network to an unprotected one, but disallowing connections in the opposite direction.

When a computer in the protected network establishes a connection with an external server, the stateful packet filter will allow the server’s response packets in to the protected network. When the original connection is closed, however, the packet filter will block all further packets from the unprotected network (unless, of course, they have been explicitly allowed).

Application-Layer Gateways: Application Proxies

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Installation

The second main kind of firewall is the application-layer gateway.

These gateways act as a middleman in connections between external systems and protected ones. With such gateways, packets aren’t forwarded so much as translated and rewritten, with the gateway performing the translation.

The translation process on the gateway is called a proxy server, or

proxy for short. Because each proxy serves only one or a few welldefined application protocols, it is able to analyze and log protocol usage at a fine-grained level, and thereby offer a wide range of monitoring and security options.

The analysis can be especially intensive at the application level, because the application data transferred conforms to standardized protocols. The firewall knows about and can inspect every aspect of the data flow. This also means that small, manageable modules can be used for each kind of data, which in turn means the system is less prone to problems due to implementation errors.

For example, this security system includes the following proxies:

• An HTTP proxy with Java, JavaScript and ActiveX

• An SMTP proxy, which scans e-mails for viruses and controls email distribution

• A SOCKS proxy which acts as a generic authenticating circuit-level proxy for many applications

Application-level gateways have the advantage of allowing the complete separation of protected and unprotected networks. They ensure that no packets are allowed to move directly from one network to the other. This results in reduced administration costs: as proxies ensure the integrity of protocol data, they can protect all of the clients and servers in your network, independent of brand, version, or platform.

Protection Mechanisms

Some firewalls contain further mechanisms to ensure added security.

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Installation

One such mechanism is supporting the use of private IP addresses in protected networks through Network Address Translation (NAT), specifically …

• Masquerading

• Source NAT (SNAT)

• Destination NAT (DNAT)

This allows an entire network to hide behind one or a few IP addresses, and hides the internal network topology from the outside.

This allows internal machines to access Internet servers while making it is impossible to identify individual machines from the outside.

Using Destination NAT, it is nevertheless possible to make internal or DMZ servers available to the outside network for specific services.

Example: An external user

(see graphic on left) with the IP address 5.4.3.2 sends a request from port 1111 to the web server in the DMZ. The user knows only the external IP and port (65.227.28.232, port

88).

Using DNAT, the firewall changes the destination address of the request to the internal address of the web server (192.168.2.99, port

80), and sends it to the web server. The web server then responds, using its own internal IP address (192.168.2.99, Port 80), and sends the reply back to the user. The firewall recognizes the packet from the user’s address and changes the source address of the reply from the

9

Installation web server’s address to its own external address (65.227.28.232, port 88).

Another advanced protection mechanism is the VPN technology. To meet the demands of modern business, IT infrastructures must offer real-time communication and allow close cooperation between business partners, consultants, and branch offices. Increasingly, these demands are being met through the use of extranets, which usually operate either

• via dedicated lines, or

• unencrypted over the Internet.

Each of these approaches has advantages and disadvantages which must be balanced according to cost and security requirements.

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Installation

Virtual Private Networks (VPN) provide a cost-effective solution to this problem: they can connect LANs over the Internet using encrypted connections, thus enabling secure, transparent, end-to-end communication without the need for leased lines. This is especially useful when an organization has many branch offices connected to the

Internet. IPSec technology provides a standard model for these secure connections.

These secure connections can be used automatically, independent of the data being transferred – this protects the data without requiring extra configuration or passwords on the client systems.

At the other end of the connection, the data is transparently decoded and forwarded to the recipient in its original form.

The Firewall component of this security system is a hybrid of the preceding protection mechanisms, combining the advantages of each:

The Stateful Inspection Packet

Filter offers the platform-independent flexibility to define, enable, and disable all necessary services.

The Proxies incorporated into this security system transform it into an Application Gateway capable of securing vital services such as

HTTP, Mail and DNS. Further, the SOCKS proxy enables generic circuit-level proxying for all proxy-aware applications.

VPN, SNAT, DNAT, Masquerading and static routing capabilities make the firewall a powerful connection and control point on your network.

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Installation

2.Installation

The installation of this Internet security system proceeds in two main steps: loading the software, and configuring the system parameters.

The initial configuration required for loading the software is performed through the console-based Installation Menu, while the final configuration and customization can be performed from your management workstation through the web-based WebAdmin interface.

While configuring your system, please note that the

WebAdmin system provides additional information and help through its Online

Help system. To access this system, simply click the button marked ?.

The following pages contain configuration worksheets where you can enter the data (such as default gateways and IP addresses) you use to set up your system. We recommend you fill these out as you configure the system, and that you keep the worksheets in a safe place for future reference.

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Installation

2.1. System Requirements

The requirements for installing and using this security system are:

Hardware

• Processor: Pentium II or compatible (up to 100 users)

• Processor: Pentium III or compatible (above 100 users)

• 256 MB RAM

• 8 GB IDE or SCSI hard drive

• Bootable IDE or SCSI CD-ROM drive

• 2 or more PCI Ethernet network cards

• For wireless LAN access: a wireless LAN PCMCIA card with the

Prism2, Prism2,5 or Prism3 chipset (or compatible)

Important Note:

The High Availability (HA), Wireless LAN, and Virtual LAN subsystems require extra hardware. Please check the Hardware

Compatibility List for Novell Security Manager powered by

Astaro

, available at

http://www.novell.com/documentation/

nsma51 for compatibility.

To make Heart Beat monitoring of the High Availability (HA) system easier, we recommend using network cards from the Hard-

ware Compatibility List (HCL) for all interfaces. The installation of the

HA system is described in detail in chapter on page 98.

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Installation

Administration PC

• Correct configuration of the Default Gateway, IP Address, and

Subnet Mask

• An HTTPS-compliant browser (Microsoft Explorer 5.0 or newer,

Netscape Communicator 6.1 or newer, or Mozilla 1.6+):

JavaScript must be activated.

The browser must be configured not to use a proxy for the IP address of the security system’s internal network card (eth0).

Browser configuration is discussed in chapter on page 221.

Example Configuration

As in the diagram on the left, the security system should be the only link between the internal and external networks.

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Installation

Address Table

IP Address Network Mask Default Gateway

Internal network interface

External network interface

DMZ network interface 1)

Network interface for the HA system 2)

___.___.___.___ ___.___.___.___ ___.___.___.___

___.___.___.___ ___.___.___.___ ___.___.___.___

___.___.___.___ ___.___.___.___ ___.___.___.___

___.___.___.___ ___.___.___.___

1) The third and further network cards are optional.

2) Network interface for the High Availability system.

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Installation

2.2. Installation Instructions

What follows is a step-by-step guide to the installation process.

Attention:

The installation process will destroy all existing data on the hard disc!

Preparation

Before installation, please make sure you have the following items ready:

• the security system CD-ROM

• the license key for the security system

• the address table, with all IP addresses, network masks and

default gateway filled in

2.2.1.

Software Installation

The first part of the installation uses the Installation Menu to configure basic settings.

The setup program will check the hardware of the system, and then install the necessary software on your PC.

1.

Boot your PC from the CD-ROM Drive:

Select the appropriate installation mode for your computer.

Three pre-compiled kernel options are available for this purpose:

Default: Kernel for systems with a CPU.

SMP: Kernel for systems with several processors.

Classic: Kernel for systems with a CPU, in which the support for

APIC (Advanced Programmable Interrupt Controller) and ACPI

(Advanced Configuration and Power Interface) is disabled.

Since in older hardware components APIC and ACPI are often not supported, we recommend using the Classic Kernel in this case!

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Installation

2.

Key Functions during the Installation (Step 1):

In order to navigate through the menus, use the following keys.

Please note the additional key functions listed in the green bar at the bottom of the screen.

Cursor keys: Use these keys to navigate through the text boxes

(e.g., the license agreement or when selecting a keyboard layout).

Enter key: The entered information is confirmed, and the installation proceeds to the next step.

ESC key: Abort the installation.

Tab key: Move between text boxes, entry fields, and buttons.

Press Enter to continue.

Attention:

The installation will destroy all data on the PC!

Confirm the following security question by clicking the F8 key.

3.

Keyboard Layout (Step 2):

Use the Cursor keys to select your keyboard layout and press

Enter to continue.

4.

Hardware Detection (Step 3):

The software will check the following hardware requirements:

CPU, size and type of hard drive, CD-ROM drive, network cards, and IDE or SCSI controllers.

If your system does not meet the minimum requirements, the installation will report the error and abort.

5.

Time and Date (Step 4):

Use the Cursor keys to select your country and press Enter to confirm.

Use the Cursor keys to select your time zone and press Enter to continue.

17

Installation

Next, enter the current time and date in the entry field. Use Tab and the Cursor keys to switch between entry fields. Invalid entries will be rejected.

Confirm your entries with the Enter key.

6.

Network Card Selection and Configuration (Step 5):

In order to use the WebAdmin tool to configure the rest of your security system, you must now configure a card to be the in-

ternal network card (eth0).

Choose one of the available network cards from the list and confirm your selection with the Enter key.

Next, define the IP address, network mask, and default

gateway for this network card.

Example:

Address: 192.168.2.100

Netmask: 255.255.255.0

You must enter a value in the Gateway field if you wish to use the WebAdmin interface from a workstation outside the subnet defined by the netmask. Note that the gateway itself must be within the subnet.

For example, if you are using a network mask of 255.255.255.0, the subnet is defined by the first three values of the address: in this case, 192.168.2. If your administration computer is at, for example, 192.168.10.5, it is not on the same subnet, and thus requires a gateway to be configured here. The gateway router must have an interface on the 192.168.2 subnet, and must be able to contact the administration computer.

In our example, assume the gateway is at 192.168.2.1:

Gateway: 192.168.2.1

If the administration computer is on the same subnet as the internal network card (in our example, if its address is

18

Installation

192.168.2.x) it does not need a gateway. In this case, enter the following value here:

Gateway: none

Confirm your entries with the Enter key.

7.

License Agreement (Step 6):

Note:

Please read the license agreement carefully.

Press F8 to agree to the terms of the license.

8.

Final Notes (Step 7):

Attention:

Please read the notes and warnings presented during the installation carefully. After confirming them, all existing data on the PC will be destroyed!

If you wish to change your entries, press F12 to return to Step

1. Otherwise, start the installation process by pressing the F8 key.

9.

Installing the Software (Step 8):

The software installation process can take up to a couple of minutes. You can follow the progress of the installation using the four monitoring consoles:

There are four consoles available:

Main Installation (Alt + F1).

Interactive bash Shell 1 (Alt + F2).

Installation Log (Alt + F3).

Kernel Log (Alt + F4).

When the installation process completes, remove the CD-ROM from the drive and connect the eth0 network card to the internal network.

19

Installation

Except for the internal network card (eth0), the sequence of network cards normally will be determined by PCI ID and by the

Kernel drivers.

The sequence of network card names may also change if the hardware configuration is changed, especially if network cards are removed or added.

10.

Reboot the System:

Reboot the security system by pressing Ctrl + Alt + Del or the

Reset button.

During the boot process, the IP addresses of the internal network cards are changed. The Install Routine console (Alt + F1) may display the message

No IP on eth0

during this time.

After the security system has rebooted (a process which, depending on hardware, can take up to five minutes), ping the IP Address of the

eth0 interface to ensure it is reachable.

If no connection is possible, please check for the following possible problems.

Error:

The security system is not reachable from the internal network.

Possible Causes:

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Installation

• The IP address of the security system is incorrect

• The IP address of the client computer is incorrect

• The default gateway on the client is incorrect

• The network cable is connected to the wrong network card

• All network cards are connected to the same hub

Note:

If you connect to the Internet through a DSL connection, please read the installation instructions at

http://www.novell.com/documentation/nsma5.

2.2.2.

Configuring the Security System

The rest of the configuration will use the WebAdmin interface, accessed through a standard web browser (e.g., MS Internet

Explorer) from your administration PC:

1Start your Browser and open WebAdmin:

Before you can access the WebAdmin interface, you must make sure that your browser is configured correctly. Please see in chapter on page 221 for more details.

Once your browser is correctly configured, start it and enter the management address of the security system (the internal IP address configured for eth0) as follows: https://IP Address.

(In the example from step 6 above, this would be https://192.168.2.100)

A security notice will appear. When you generate a certificate for WebAdmin in a later step, this notice will disappear.

Further information on generating and installing certificates can be found in chapter on page 95.

For now, simply accept the security notice by clicking the Yes button.

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Installation

The first time you start WebAdmin, two windows will open: the first contains the License Agreement, and the second is used for Setting System Passwords.

11.

Complete the License Agreement:

In the License Agreement window, accept the terms of the license by clicking the I agree to the terms of the license selection box.

Note:

Please read the terms of the license carefully.

12.

Set the System Passwords:

In the Setting System Passwords window, enter the passwords for the Internet security system.

Security Note:

Use a secure password! Your name spelled backwards is, for example, not a secure password – while something like xfT35$4 would be.

You will only be able to start WebAdmin once you have entered passwords for the functions listed below. Enter the password for each service, and then re-enter it in the text field labeled

Confirm. The usernames are pre-defined, and cannot be changed.

WebAdmin user: access to WebAdmin

This user is called admin.

Shell Login user: access to SSH

This user is called loginuser.

Shell Administrator user: administrator privileges in the entire security system.

This user is called root.

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Installation

Security Note:

Use different passwords for the Shell Login and Shell

Administrator users.

Configuration Manager User (optional): You need this password, if you wish to configure the Security system with the

Configuration Manager.

Boot Manager (optional): If set, the password will prevent unauthorized users from changing boot-time parameters.

Confirm the entered passwords by clicking Save.

13.

Log in to WebAdmin:

User: admin

Password: Password of the WebAdmin user

Please note that passwords are case-sensitive!

Click Login.

Note:

Please follow steps through in the order listed below.

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Installation

14.

Uploading the License Key:

In the System tab, open the Licensing menu and upload the

license key under the License File window.

Note:

When using a license with the High Availability (HA) option, you must import the License Key to both security systems

(Normal and Hot Standby mode).

For more information on Licensing, see chapter on page 44.

15.

Configure Basic Settings:

In the System tab, open the Settings menu and enter the following setting:

Administrator E-Mail Addresses: Enter the e-mail address of the administrator here.

You can find further information about these functions in chapter on page 39.

In the Network tab, open the Hostname/DynDNS menu and enter the following settings in the General System Settings window:

Hostname: Enter the Hostname for this security system.

A domain name may contain alphanumeric characters, periods, and hyphens. The end of the name must be a valid top-level domain, such as “com”, “de”, or “org”. The Hostname will be included in all Notification E-Mails.

Save the settings by clicking Save.

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Installation

16.

Configure the internal Network Interface (eth0):

In the Network tab, open the Interfaces menu and check the settings for eth0 network card.

The settings for this network card are based on the information entered during the software installation. After starting the security system, they are shown in the Current Interface

Status window.

If you wish to change settings for this card, for example changing the configured name, please open the Edit Interface window by clicking the edit button and make these changes now.

Attention:

If you change the IP address of the eth0 network card, you will be locked out of WebAdmin.

The configuration of network cards and virtual interfaces is described in chapter on page 122.

17.

Configure the internal Network:

In the

Definitions tab, open the

Networks menu and check the settings for the internal network. Three logical networks were defined during installation based on your settings for the internal network card (eth0):

The interface Internal (Interface), consisting of the defined IP address (example: 192.168.2.100) and the host network mask

255.255.255.255.

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Installation

The broadcast network Internal (Broadcast), consisting of the broadcast address (example: 192.168.2.255) and the host network mask 255.255.255.255.

The internal network Internal (Network), consisting of the defined IP address (example: 192.168.2.0) and the defined network mask (example: 255.255.255.0).

Defining new Networks is described in chapter on page 106.

18.

Configure the external Network Card:

In the Network tab, open the Interfaces menu and configure the interface to be used to connect to the external network

(Internet). The choice of interface and the required configuration depend on what kind of connection to the Internet you will be using.

The configuration of network cards and virtual interfaces is described in chapter on page 122.

19.

Define Masquerading Rules:

If you wish to use private IP addresses for your internal network and wish to connect directly (without proxies) to the Internet, you can now establish the relevant rules in the Network/

NAT/Masquerading menu.

More information about DNAT, SNAT and Masquerading can be found in chapter on page 168.

IP routing entries for networks directly connected to the security system’s network cards (Interface Routes) will be added automatically.

If required, you can also define routing entries manually using the Routing menu. This will, however, usually only be necessary in complex network environments.

26

Installation

20.

Configure the DNS Proxy:

In order to speed up name resolution, you can specify a local

DNS name server (or one provided by your ISP) in the

Proxies/DNS menu. Otherwise, the security system will automatically use the root name servers.

If you wish to use the proxy, you should configure the DNS

Proxy settings now.

More information about configuring the DNS Proxy can be found in chapter on page 241.

21.

Connect other Networks:

If you wish to connect other internal networks to the security system, attach their cables now.

22.

Configure the HTTP Proxy:

If computers on the internal network should use the HTTP proxy to connect to the Internet, open the HTTP menu in the Proxies tab and click Enable.

It might be necessary to configure the browsers to allow the computers in the internal network to access the Internet by using the HTTP proxy afterwards - e.g. if the proxy was configured for the standard operation mode.

The configuration of the HTTP proxy is described in more detail in chapter on page 221.

23.

Configure the Packet Filter:

In the Rules menu under the Packet Filter tab, you can establish packet filtering rules.

By default, all packets are filtered until you explicitly enable certain services. New rules are added to the bottom of the list, and are inactive until explicitly enabled. The rules are processed starting with the first and moving down the list, stopping at the first applicable rule. To activate a rule, click the status light once

– the status light will turn green.

27

Installation

Please note that, because the security system uses Stateful

Inspection, only the connection-building packets need be specified. All response packets will automatically be recognized and accepted.

Configuring the Packet Filter is described in chapter on page

199.

24.

Debug Packet Filter Rules:

With the Packet Filter Live Log function In the Packet Filter/

Advanced menu, you can see which packets the packet filter is filtering. If you have problems after installing your security system, this information can be helpful in debugging your filtering rules.

The Packet Filter Live Log function is described in chapter on page 214.

25.

Install System and Virus Scanner Updates:

You should download and install the latest System Up2Dates as soon as possible.

If you have a license for the Virus Protection option, you should also run the Pattern Up2Date system.

The Up2Date Service option is described in chapter on page

48.

When you’ve completed these steps, the initial configuration of your security system is complete. Click the Exit tab to leave WebAdmin.

Problems

If you have problems completing these steps, please visit the Novell

Support Forum at: http://support.novell.com/forums/2sm.html

28

Installation

3.WebAdmin

The WebAdmin tool allows you to configure every aspect of the

Internet security system. This chapter explains the tools and concepts used by WebAdmin, and shows how to use the built-in online help system.

WebAdmin has five main components:

(1) Info Box

(2) Tabs

(3) Menus

(4) Online help

(5) Refresh

29

Installation

3.1. Info Box

The system time and time zone are always displayed in the top left-hand corner of the screen. If you roll the mouse over the time display, the Info Box will appear, containing the following information:

Uptime: Displays how long the security system has been running without a restart.

User: Displays which user is currently logged in to WebAdmin, as well as the client the user is logged in from.

Last Login: Displays when and from which client WebAdmin was last used.

3.2. Tab List

The Tab List on the left of the screen organizes the various menus according to subject.

To list the menus contained under a subject heading, simply click the tab: the available menus will appear below. For ease of use, chapter 5, “Using the

Security system”, has been structured to match the order of topics in the Tab List.

30

Installation

3.3. Menus

Every function of the security system has its own separate menu in

WebAdmin. This chapter describes the tools and displays used in the configuration menus.

3.3.1.

The Status Light

Many features and subsystems of the security system can be enabled or disabled while the system is running.

A status light displays the current status of such subsystems:

• red = Function is disabled

• green = Function is enabled

For many features, the configuration options and tools will not be displayed until the status light is green.

3.3.2.

Selection Field

With the selection fields the allowed networks and

allowed users are assigned to the functions and services.

Adding Objects to the Selected List:

1.

In the Available list, select the object (e.g., the network or user) you wish to add by clicking its name.

2.

You can select more than one object at a time by holding the

CTRL key while you make your selection.

Click the Left Arrow button.

31

Installation

The names you selected in the Available window will be moved to the Selected window.

Removing Objects from the Selected List:

1In the Selected list, choose the objects (networks or users) you wish to remove by clicking them.

3.

Again, you can select more than one object at a time by holding the CTRL key while you make your selection.

Click the Right Arrow button.

The objects will be moved back to the Available window.

3.3.3.

The Selection Table

Use the selection table to assign the corresponding au-

thentication method or an

interface to the functions and services.

The authentication method

(Menu System/User Au-

thentication) and the interfaces (Menu Network/

Interfaces) must first be configured by the administrator. The picture above shows a selection table for interfaces. The picture below shows a table for the selection of authentications.

The functions with the entries:

The functions are only activated if the corresponding entry has been selected. The position of the entry is displayed in the left column. Use the buttons in the right column to change the order of the entries.

Clicking on the buttons or moves the respective entry one line up and/or one line down.

Clicking on the buttons or moves the respective entry in the first

32

Installation and/or last line of the table.

Assigning the authentication method or interface:

Select the authentication method and/or interface by clicking on the check box.

This activates the new setting and moves it into the last line of the already selected entries.

Disabling an authentication method or interface:

Disable an entry by clicking on the activated check box in the corresponding line.

The entry is immediately disabled. The functions in this line will then be no longer available.

3.3.4.

Drop-down Menus

Drop-down menus are used to configure functions that can have only one of a few values. To use, simply select the value from the list: as a rule, values chosen in drop-down menus take effect immediately.

33

Installation

3.3.5.

Lists

Lists are used, in contrast, to configure functions that not only allow more than one value to be configured, and where the listed objects do not need to be first defined by the administrator. In some instances, the order of the configured values is also relevant.

Each list can contain many pages of values, and each page displays ten entries.

The Interfaces menu, instance, uses a list to allow access to the Wireless LAN

Access Point.

The first row of the table shows the number of pages in the list on the left (the current page is shown in white) and the total number of entries on the right (next to the # symbol). Note that, if you roll the mouse over one of the red page numbers, a tooltip appears showing the first and last entries on that page (see picture at right). This can help to navigate quickly between pages.

The second row contains tools to control the display of the list. Note that these do not change the configuration information, but rather the way in which these entries are displayed within WebAdmin. In cases where order is important, only the order indicated by the numbers next to entries has an effect on the configuration of the function. The buttons and in the left-hand column display the list in ascending and descending numerical order respectively, while the and

34

Installation buttons in the middle column display the list in ascending or descending alphabetical order.

The functional order, as indicated by the numbers to the left of each entry, can be adjusted using the buttons in the right-hand column. A click on the or button in this column will move the entry one row up (i.e., towards 1) or down (towards the end of the list) respectively.

Similarly, you can move an entry to the very beginning or end of the list by clicking the or buttons in this column, respectively.

Add entry: Type a value in the text-entry field and click Add.

The new value will appear in the last row of the table.

Delete entry: By double-clicking an entry, you can remove it from the list.

Edit entry: If you click an entry once, it will appear in the entry field.

Edit the entry as desired and click the Replace button to put it back into the list.

3.4. Online Help

Every menu in WebAdmin screen which provides a short explanation of the available configuration options.

You can open the help screen by clicking the ? button at the top righthand corner of the screen.

35

Using the Security System

3.5. Refresh

To load the menu again, click the Refresh button.

Don’t use the Refresh button of the tool bar of your browser to actualize the menu – otherwise you are logged-off the session and have to log in again under the WebAdmin configuration tool!

36


4.Using the Security System

We have already seen the web-based configuration tool WebAdmin in action during the installation process. This chapter will describe how to use WebAdmin to control and monitor your security system on a day-to-day basis.

The specific settings, what they do, and how to change them will be described step-by-step. Please look to chapter for a more general description of how to use the tools provided by the WebAdmin interface.

Please remember that the goal in configuring a security system like this should be to enable only the features necessary for correct functionality. In general, you should restrict in- and outbound connections to those explicitly required.

Tip:

Draw up a plan of your network and determine which computer is to have access to which services before configuring the security system. This will simplify the configuration process and save you a lot of time.

Configure the system as follows:

1Define all the required networks and hosts.

4.

5.

Define the necessary services.

Define the system rules and proxies.

Starting WebAdmin:

37


1Start your browser and enter the address of the Security system

(i.e., the address of the eth0 interface) as follows: https://IP Address.

6.

7.

In our example from step 6 of the installation instructions in chapter , this would be https://192.168.2.100.

If you have not yet generated a Certificate for your WebAdmin site, a Security notice will appear.

More information on how to install a certificate is available in chapter on page 95.

Click the Yes button on the security notice to continue.

Log in to WebAdmin.

8.

User: admin

Password: the password of the

WebAdmin user.

Both entries are case-sensitive!

Click Login.

Another administrator is already logged-in:

If another administrator is already logged in to

WebAdmin, a notice will appear on screen. The IP address shows you which computer the other administrator is using.

The kick function allows you to end the other administrator’s session.

In the Reason field, type a reason for ending the other user’s session and click Login.

38


You are now logged in, and can use the WebAdmin to manage the system.

4.1. Basic Settings (System)

The menus under the System tab allow you to configure and manage the basic settings of your security system.

4.1.1.

Settings

Administrator Contact

E-Mail Addresses: Whenever certain important events occur, such as portscans, failed logon attempts, or reboots, as well as whenever the self-monitor or Up2-

Date systems generate alerts or reboots, the security system will send a notification e-mail to the administrator through the e-mail addresses entered into the ordered list. At least one e-mail address must be present; otherwise the E-Mail Reporting function will be disabled.

To add a new e-mail address, enter it in the entry field and click Add.

Please see chapter on page 34 to learn more about the functions of the ordered list.

Important Note:

Notification E-Mails can only be sent to the administrator when the

DNS Proxy is enabled and configured (chapter on page 241), or when the SMTP menu (chapter on page 251) has been configured with a route for incoming e-mails.

Use external Indicators: This option is only available on appliance systems with an attached LCD indicator. This option allows you to turn the LCD display on or off.

Time Settings

39


This menu can be used to set the time and date of the security system. The date and time can be set manually with the help of the drop-down menu or can be automatically synchronized using the NTP-server (Network

Time Protocol). Please note that important changes in the time setting will appear as gaps in the Reporting and Logging.

Important Note:

We do not recommend changing the system time for daylight savings time. Instead, we recommend setting the system clock to Central

European Time (CET). In summer, this corresponds to a deviation of less than one hour.

When system time settings are changed, the following “time warp” effects may be noticeable:

Moving forward (e.g., standard time to daylight saving time)

• The timeout for WebAdmin will expire and your session will no longer be valid.

Time-based reports will have no data for the skipped hour. In most graphs, this time period will appear as a straight line in the amount of the old value.

• Accounting reports will contain values of 0 for all variables during this time.

Moving backward (e.g., daylight saving time to standard time)

• There are already log data for the corresponding span of time in the time-based reports that for system purposes come from the future: These data will not be overwritten.

• Log data will be written as normal when the time point before the reset is reached again.

• Most diagrams will display the values recorded during this period as compressed.

40


• Accounting reports will retain the values recorded from the

“future”. Once the time point of the reset is re-reached, the accounting files will be written again as normal.

Because of these difficulties, we recommend that the time be set only during the first configuration, and that only minor adjustments be made later. We recommend setting the system clock to Central

European Time (CET). This is the original time. The system then runs always in CET, not in in CEST (Central European Summer Time). We recommend, not to change the time for summer, especially not when the collected reporting and accounting data are treated.

Manual configuration of system time: a. Open the Settings menu in the System tab. b. In the Time Settings window make the following settings in the given order:

Use NTP Server: In order to configure the system clock manually, please ensure that No NTP Server is selected here. In this case, the Please select drop-down menu will be displayed.

If a NTP Server is selected, select No NTP Server from the drop-down menu.

Time Zone: Now select the time zone.

Note:

Changing the timezone will only change the current system time if you are using an NTP server to control time settings.

Set Time: Enter the current date and time here.

41


Important Note:

Take note of the issue date of your License Key. If this date is after the current date set on the security system, the license will be deactivated.

The 30-day Evaluation License will not automatically activate.

9.

Click the Save button to save these settings.

The time settings of the security system will now be updated.

Synchronizing system time with NTP Server

Before the system clock of the Internet security system can be synchronized with an external server, this server must be defined as

NTP Server. The NTP Server will be defined as a network consisting of only one computer.

The definition of networks is covered in greater detail in chapter on page 105. If the NTP server has already been defined, please begin with step .

1Open the Networks menu in the Definitions tab.

2In the Name entry field enter a distinct Name.

Allowed characters are: Letters of the alphabet, digits from 0 to 9, hyphen, space, and underscore characters. The name must be fewer than 39 characters long.

10.

11.

Now enter the IP Address of the NTP Server.

In the Subnet Mask entry field, enter the network mask

255.255.255.255.

Now confirm your settings by clicking on the Add button. 12.

13.

WebAdmin will now check your entries for semantic validity.

Once accepted, the new network will appear in the network table.

Open the Settings menu in the System tab.

42


14.

In the Time Settings window make the following settings in the given order:

Time Zone: Now select the time zone.

Use NTP Server: Select the NTP Server here.

The system clock of the Internet Security system will be synchronized with the external NTP server every hour.

SSH (Shell Access) Settings

Secure Shell (SSH) is a textbased access mode for the security system intended only for advanced administrators. In order to access this shell, you will need an SSH Client, which comes standard with most Linux distributions. For MS-Windows, we recommend Putty as SSH Client. Access through SSH is encrypted, and cannot be read by eavesdroppers.

The Shell Access function is enabled by default, once you have entered a password for the configuration through the Configuration

Manager in the Setting System Passwords window.

If you wish to access the security system through SSH, the SSH Status light must be enabled (status light shows green).

The SSH protocol uses name resolution (valid name server) if no valid name servers are found, SSH access attempts will time out. The time-out takes about a minute. During which time the connection seems to be frozen or failed. Once the time-out has expired, the connection process continues without further delay.

You must also add the networks allowed to access the SSH service in the Allowed Networks selection field. In order to ensure a seamless installation process, the Allowed networks field contains the Any option by default, this means that any computer can access

43

Using the Security System the SSH service. Networks can be defined in the

Definitions/Networks menu.

Security Note:

By default, anyone has access to the SSH service. The Allowed

Networks field contains the Any option. For increased security, we recommend that access to the SSH service be limited. All other networks should be removed!

We recommend that the SSH service be disabled when not in active use.

Password and Factory Reset

The Password Reset function allows you to set new passwords for the Security system.

If you log in to the WebAdmin configuration tool for the first time after this action, the Setting

System Passwords window will be displayed. This allows you to set optional passwords, such as the Configuration Manager Password.

Halt System will shut down the Security system. After the restart, the Setting System Passwords window will be displayed at first.

The Factory Reset function resets all configuration settings and options to their original state. All data entered after the initial installation will be deleted, including the HTTP Proxy Cache, the entire

E-Mail Queue, Accounting and Reporting data, passwords, and uninstalled Up2Dates.

The software version will not change. That is, all System Up2Dates and Pattern Up2Dates that have been installed will be retained.

4.1.2.

Licensing

44


Novell Security Manager powered by Astaro ships with a sevenday evaluation license included. No action is required to implement this license. If further evaluation is necessary beyond seven days, a

90-day demo license is available from Novell at: http://download.novell.com

The demo license activates all features of Novell Security Manager

powered by Astaro, including the base product:

• Up2Date Service

• Spam Protection

• Virus Protection for E-Mail

• Phishing Protection

• Surf Protection

• Virus Protection for Web

If you decide after the expiry of the demo license, to use the security system for your company, you’ll need the base license. This base license can then be completed with up to four functions and security packages.

This base license and the four functions and security packages contain the following modules:

• Base license: Packet Filter, VPN Gateway and Intrusion Protection

• Maintenance & Support: Up2Date Service

• High Availability

• Secure E-Mail Subscription: Spam Protection, Virus Protection for

E-Mail, Phishing Protection

• Secure Web Subscription: Surf Protection, Virus Protection for

Web

The price of the company version depends on the size of the network to be protected, the scope of support and the modules, subscribed to in addition to the base license.

For more information, please visit our website under: http://www.novell.com/products/securitymanager

45


Licensing the Internet security system:

In order to license the Internet security system, you need a valid license string on the local host, so that you can enter it to the

Internet security system through the WebAdmin configuration tool.

Note:

When using a license with the High Availability (HA) option, you must enter the License strings to both security systems (Normal and Hot Standby mode).

1Open the Licensing menu in the System tab.

2Enter the license string(s) in the License Strings entry field.

15.

Click on the Save button.

The system will require between 30 and 60 seconds to process this information. After successful registration, the Installed Licenses window will contain the details of your license.

Installed Licenses

After successful registration of the Internet security system, the

Installed Licenses window will show the details of your license.

Licensed Users (IPs)

The functions in this window are used for licenses that do not allow for an unlimited number of users (IP addresses).

View current User (IP) Listing: The table contains all IP addresses that are relevant for the licensing. The current user table is always loaded when this menu is opened.

The table will also be displayed if the license is an unlimited version.

46


Reset User (IPs) Listing: If you wish to reconfigure the internal network, you can reset the user table by this action. Then there is a reboot - the system will shut down completely and reboot.

This action is enabled by clicking on the Start button.

47


4.1.3.

Up2Date Service

The Up2Date Service makes it easy to keep your security system software updated: New virus definitions, system patches, and security features will be installed to your current system. transferred over a secure channel. Any unsigned or forged Up2Date packages are rejected and deleted.

All Up2Date data are digitally signed and encrypted, and are

A number of servers are maintained for both System Up2Date and

Pattern Up2Date that are dialed in the given sequence. If the first

Up2Date server is not available, the system will automatically query the next system or pattern Up2Dates in the list.

Important Note:

In order to download updates, the Up2Date Service makes a TCP connection to the update server on port 443. The security system will permit this connection without any adjustment. If there is another security system in place upstream, you must allow the communication via the port 443 TCP to the update servers.

Note:

When using the High Availability (HA) system, please note the special functions of System Up2Date.

48


System Up2Date

The System Up2Date function allows you to import system patches and new security features into your Internet security system. The

Up2Date packages can be downloaded either manually over an encrypted connection or automatically from the Update Server. If you don't have an Internet connection, you can also import Up2Date packages from a local volume.

Newly imported Up2Date packages are presented with their respective version number and file name in the Unapplied Up2Dates table. These Up2Date packages have not been installed yet!

In order to get further information, touch the blue info button with the cursor. If the info button is highlighted red, there will be an automatic restart of the Security system after the installation of the

System Up2Date package.

Note:

If you are using the High Availability (HA) system, please note the special notes for the import and installation of the System Up2-

Dates. The HA system is described in chapter on page 98.

49


Manually downloading System Up2Dates:

1.

Open the Up2Date Service menu in the System tab.

2.

In the System Up2Date window, click the Start button under Prefetch Up2Dates now.

The system will now check if there are any new updates on the

Update server, and will download any updates found. Details on the

Up2Date process can be found in the Log

Window, shown in realtime (left-hand picture).

When the message appears, the process has completed successfully.

DONE

The Unapplied Up2Dates table lists any updates that have been downloaded but not yet installed!

If you are using the HA system, unapplied updates will be listed in the Unapplied Up2Dates Master window.

Automatic download of System Up2Dates:

1Open the Up2Date Service menu in the System tab.

2Click the Enable button under Prefetch Up2Dates automatically.

16.

In the selection menu Interval, specify how often the security system should contact the Up2Date Server to check for new System Up2Dates.

The available choices are: every hour, every day, or once per week.

50


Newly imported Up2Date packages are presented with their respective version number and file name in the Unapplied Up2Dates table. Further information is available by clicking the Info button.

Note that the Unapplied Up2Dates in the table have not yet been installed yet!


Loading System Up2Dates from a local disk:

The filename of an Up2Date update consists of the version number,

tar to signify it is an encrypted archive file, and the file extension .

gpg.

1.


2.

17.

In the System Up2Date window, click on the Browse button next to Import from File.

In the File Upload window, choose the Up2Date packages you would like to load and click on the Open button.

Important Note:

When using Microsoft Windows, make sure not to use a UNC

Path. Instead, choose the updates by using the Look in option.

18.

In the System Up2Date window, next to Import from File, click Start.

19.

Successfully loaded updates will appear in the Unapplied

Up2Dates window with the version number and the file name.

Further information is available by clicking the Info button.

Note that the Unapplied Up2Dates in the table have not yet been installed yet!


Repeat steps 2 through 4 until all Up2Date packages have been imported.

51


Installing System Up2Dates without the HA solution:

1.


2.

In the Unapplied Up2Dates table, choose the Up2Date updates to install.

Note:

If more than one System Up2Date file is listed in the table, start the highest version. The smaller versions will be installed automatically.

20.

In the Actions column, click Install.

The progress of the Up2Date installation on system 1 will be displayed in real time in the Log Window. When the DONE message appears, the process has completed successfully.

Installing System Up2Date with the HA solution:

1.


2.

In the Unapplied Up2Dates Master table, choose the

Up2Date updates to install.

21.

In the Actions column, click Install.

The progress of the Up2Date installation on system 1 will be displayed in real time in the Log Window. When the DONE message appears, the process has completed successfully.

Then the installation automatiscally starts on system 2. During this process, the Up2Date package and the message Polled by

slave will be displayed in the Unapplied Up2Dates Slave

52

Note:

If more than one System Up2Date file is listed, start with the

smallest version. Only one package can be installed with the

HA system.


22.

table.

The table will show the message No locally stored Up2Date

packages available when the installation on system 2 has completed successfully.

If the Unapplied Up2Dates Master table lists more unapplied updates, repeat steps 2 and 3 until all updates have been installed.

The HA system is fully updated when the Unapplied Up2Dates

Master table shows the message No locally stored Up2Date

packages available and if both systems display the same version number.

Pattern Up2Date

The Pattern Up2Date function updates the virus patterns for the security system’s integrated virus scanner and the Intrusion

Protection System (IPS) with

IPS attack signatures. You can choose to update signatures manually or automatically at certain intervals.

The Latest Pattern Up2Dates table shows the date of the most recently installed Pattern Up2Date. Virus Protection Patterns and

Intrusion Protection attack signatures will be listed separately.

Manual Pattern Up2Date:

1.


2.

In the Pattern Up2Date window, click the Start button under Update now.

The system checks now, whether new Pattern Up2Date packages are available on the Update Server, downloads and installs them to the

Internet security system. Details on the complete Up2Date process

53

Using the Security System can be found in the Log Window, shown in real-time. When the

DONE message appears, the process has completed successfully.

The Installed Pattern Date will be updated when you click the

Up2Date Service under the System tab, or when you next open this menu.

When using the High Availability (HA) solution, the virus scanner on system 2 will be automatically synchronized with system 1.

Automatic Pattern Up2Date:

1.


2.

23.

Click the Enable button under Update automatically.

In the selection menu Interval, specify how often the security system should contact the Up2Date Server to check for new Pattern Up2Dates.

The available choices are: every hour, every day, or once per week.

Security Note:

Choose the hourly update option to ensure that your system is always up to date.

The automatic Pattern Up2Date is now activated. The Security system will contact the Up2Date Server at regular intervals and check for new Pattern Up2Dates. Whenever new Pattern Up2Dates are installed, the administrator will be sent an e-mail containing a list of the newest virus signatures.

When using the High Availability (HA) solution, the virus scanner on system 2 will be automatically synchronized with system 1.

Use Upstream HTTP Proxy

54


In this window you can define the connection to an Up-

stream Proxy Server. This function is required if you can only connect through such an

Upstream Proxy to HTTP and

HTTPS ports.

Defining an Upstream Proxy Server:

1Open the Up2Date Service menu in the System tab.

2Click Enable next to Status to enable the function and make the following settings:

24.

Proxy IP Address: Enter the IP address of the Upstream Proxy server into the entry field.

Proxy TCP Port: Enter the port number of the Upstream Proxy server into the entry field.


25.

If an authentication is required for accessing the Upstream

Proxy Server, enable the Use Authentication function and make the following settings:

26.

Username: Enter a username in the entry field.

Password: Enter the password in this entry field.


4.1.4.

Backup

The Backup function allows you to save the settings of your Security system to a file on a local disk.

This backup file allows you to install a known-good configuration on a new or misconfigured security system. This is especially useful in case of hardware failure, as it means replacement systems can be up and running within minutes.

55


Attention:

Version 5.0 of the security system can only load backups from version 4.021 or higher.

Install the License Key in the Licensing menu before loading the backup. Without the appropriate license, the system will only support three network cards – under certain circumstances, this can lead to

WebAdmin not being reachable.

Note:

After every system change, be sure to make a backup. This will ensure that the most current security system settings are always available. Make sure that backups are kept securely, as the backup contains all of the configuration options, including certificates and keys.

After generating a backup file, you should always check it for readability. It is also a good idea to use an external MD5 program to generate checksums: this will allow you to check the integrity of the backup later.

Restore a Backup

This window allows you to install the backup file of the configuration.

Loading a Backup:

1.

Open the Backup menu in the System tab.

2.

27.

In the Restore a Backup window next to the Upload

Backup File entry field, click on the Browse button.

In the File Upload window, choose the Backup file, you would like to load and click on the Open button.

56


Note:

When using Microsoft Windows, make sure not to use a UNC

Path for loading the backup. Select the Backup file with the help of the Look in selection window.

28.

Click on the Start button.

29.

If, during the generation of the backup file, the Encryption function was enabled, the Enter Passphrase window will open.

In the Passphrase field, enter the password.

30.

Confirm your settings by clicking Start.

31.

The security system will now load and check the backup file. If the ckecksums are correct, you will now receive the Backup

Information.

Check the Backup Information.

32.

To import the backed-up settings into the active system, click the Start button.

When the message Backup has been restored successfully appears, the process has completed successfully.

57


Create a Backup

This window allows you to create and archive a backup file of the configuration of your Security system.

Manually Creating a Backup:

1.


2.

In the Create a Backup window, in the Comment field, enter a description of this backup.

When restoring system backups, this description will be displayed to help distinguish between different configurations.

Important Note:

If the Encryption function has been enabled, the backup file will be encrypted with either the DES or 3DES algorithms, and can only be read or loaded using the correct password.

33.

To generate the backup file, click the Start button.

34.

The system will now generate a backup file. When the message

Backup has been created successfully appears, the process has completed successfully.

To copy the backup file to your local PC, click the Save button.

35.

36.

37.

On the File download menu, choose the Save file to disk and click the OK button.

Choose a descriptive file name on the Save file as menu.

The security system will automatically produce file names, consisting of backup, date and time: backup_yyyymmdd_hhmmss.abf (astaro-backup-file).

Check the generated backup file for readability by importing it back into WebAdmin and clicking on the Start button.

58


38.


Information.

Abort the restore process by opening a different menu within the tab.

Attention:

After each system change, create a new backup file. If you load a new backup file and if, for example, you have changed the IP address or forgotten the password, you might not be able to access the newly configured system.

59


Advanced

Encryption: The backup file contains all configuration settings as well as the respective certificates and keys. The Encryption function allows you to encrypt the file using DES or 3DES.

Encryption of e-mail Backup Files:

1.


2.

39.

Scroll to the Advanced window.

Enable the Encryption function by clicking on the Enable button.

40.

The Encryption function is enabled, when the status light shows green.

In the Passphrase entry field, enter the password.

Security Note:

With passwords with up to seven characters, the Backup file will be encrypted with DES and from eight characters on with 3DES.

41.

To confirm, enter the password again into the Confirmation entry field.

Click the Save button to save these settings. 42.

All Backup files that have been created manually or automatically by the system, will now be encrypted with the defined password.

Important Note:

A backup file that has been encrypted with Encryption can only be loaded to the system with the password that was used for the creation of the Backup.

Send Backups by E-Mail: The Security system can also send you automatically created backup files by e-mail, so that you don’t have

60

Using the Security System to remember to save the settings of your Internet security system manually on a data carrier. Then the file is e-mailed to the entered email address. These e-mailed files are about 100 kilobytes long.

Generating an E-Mail Backup File: a. Open the Backup menu in the System tab. b. In the Advanced window enable the Send Backups

by E-Mail function by clicking on the Enable button.

The Backups by E-Mails function is enabled, if the status light shows green.

Important Note:

If the Encryption function has been enabled, the backup file will be encrypted with either the DES or 3DES algorithms, and can only be read or loaded using the correct password.

43.

44.

The available choices are: Daily, weekly, and monthly.

In the E-Mail to field, enter the e-mail addresses, which should receive the backup files in regular intervals.

45.

Use the Interval drop-down menu to define how often backups should be made.

Click the Add button next to the E-Mail to entry field, to add this address to the ordered list.

46.

If you would like to add more addresses, repeat step 5.

If you wish to generate and send a backup file immediately, click the Start button next to Send backup now.

47.

Check the generated files for readability by importing the respective backup file and clicking on the Start button.


Information.

61


48.

Abort the restore process by opening a different menu within the tab.

Editing E-Mail Addresses:

Please see chapter on page 34 for a description of how to use the

ordered list.

4.1.5.

SNMP

The Simple Network

Management Protocol

(SNMP) monitors and manages the local network. SNMP allows the administrator to make quick queries about the condition of the network devices, such as the number and configuration of the network interfaces, the forwarded traffic, the current processes and hard disk utilization. Next to the current state, tendencies and time rows are interesting. They give a detailed insight into the functions of a network – the history can be monitored and remedied before turning into a real problem.

Configure the access rights to the SNMP service in the SNMP Access window. The users of the configured networks can then conduct queries about the SNMP server on the security system with their read only rights.

Security Note:

The SNMP data traffic (Protocol version 2) between the Security system and the network is not encrypted.

Authorizing Access to the SNMP Server:

1.

Enable SNMP Access by clicking the Enable button.

62


2.

49.

50.

From the Allowed Networks selection field, select the networks that you wish to allow for accessing the SNMP server.

Enter the Community String in this entry field.

Save your configuration by clicking Save.

In the SNMP Traps window you can define a

Trap-Server, to which relevant information for the system administration is sent as SNMP Traps. To recognize those

Traps a special SNMP monitoring software is required.

The messages, which are sent as SNMP Trap, contain the Object ID

(OID). The OID for messaging events (1500), the classification of the message (DEBUG = 0, INFO = 1, WARN = 2, CRIT = 3) and the relevant error code (000 bis 999) are attached.

Example: The notification

INFO-354: Intrusion Protection Pattern Up2Date succeeded

Intrusion Protection Pattern Up2Date succeeded has in this case the OID

1.3.6.1.4.1.

and is assigned the following string:

[<HOST>][INFO][354]

. For the wildcard

<HOST>

the hostname of the security system will be displayed.

Assigning the Trap Server:

1Enable SNMP Traps function by clicking the Enable button.

51.

The status light will show green and an advanced entry window will open.

In the SNMP Tap Assignment table, click the New Assign-

ment button.

52.

Click on the new line in the Host IP Address column.

An editing window will open.

63


53.

54.

Enter the IP address into the entry field of the server and save your entry by clicking on the Save button.

Click on the entry public in the Community String column and enter the Community String into the entry field.

The new assignment will be accepted immediately.

4.1.6.

Remote Syslog Server

This function allows you to forward log messages from the Security system to other hosts. This is especially useful for networks using a log host to collect logging information from a number of different hosts. By default, this function is disabled. A Logging Daemon, compatible with

Syslog protocol must be running on the selected host.

Attention:

In the System/Remote Syslog Server menu, do not select one of the security system’s interfaces (such as eth0) as the destination address (host).

Host: Enter the host, which should receive logging information in the drop-down menu. When a host has been selected, log forwarding is enabled immediately: no further messages are displayed.

In order to select a logging host (i.e., a network with netmask

255.255.255.255) you will first have to define it in the Defin-

itions/Networks menu. The definition of networks is covered in greater detail in chapter on page 105.

Service: The Syslog protocol is set by default. You can also use this drop-down menu to configure the service ( port) that should be used on the remote server.

64


Logs: This selection field allows you to select log files that should be delivered to the remote host.

65


4.1.7.

User Authentication

The security system supports User Authentication using the

SOCKSv5, SMTP, and HTTP proxy services and can control which users are allowed to use which services. User accounts can be defined on the security system, through the Definitions/Users menu. Or on an external user database. Supported external databases include

RADIUS, SAM (Windows NT/Windows 2000/XP-Server), Microsoft

OpenLDAP. If an external user database is already present on the network, you can use it instead of having to re-enter user accounts on the security system itself.

Important Note:

Please note, that several authentication methods cannot be supported at the same time.

In MS Windows based networks the Domain Controller (DC) manages access to a set of network resources (e.g., applications, printers, etc.) for a group of clients. The user needs only to log in to the domain to gain access to the resources. A Domain Controller is a server that is running a version of the MS Windows 2000 Server or

2003 Server operating system and has Active Directory (AD) installed, which is Microsoft’s trademarked directory service.

A directory service provides a centralized location to store information in a distributed environment about network devices, services, and the people who use them. For MS Windows users it provides account information, privileges, profiles, and policy. When an authentication method is used together with Active Directory and with the corresponding settings, the authentication, e. g. before accessing an own

Service is no longer made by the security system but by the Active-

Directory-Server.

User Authentication requires users to identify themselves before using network services. In comparison with an IP-based access control the

66

Using the Security System user-based access control allows for user-based Accounting in the

HTTP-Proxy access protocol.

Proxy Service and Authentication Methods

The SOCKSv5, SMTP, and HTTP services can be configured to allow or disallow clients based on IP address or on username and password combinations. In order to use User Authentication, you must select at least one database against which the security system should authenticate users. If user authentication is enabled and no database is selected, the proxy service cannot be used.

The security system supports user authentication against ...

• a RADIUS Server

• an NT SAM user list

• an Active Directory/NT Domain Membership

• an LDAP Server

• an internal database defined in WebAdmin

The five user databases can be checked one after the other.

4.1.7.1.

RADIUS

RADIUS stands for Remote Authentication Dial In User Service and is a protocol for allowing network devices (e.g., routers) to authenticate users against a central database. In addition to user information, RADIUS can store technical information used by network devices. Such as protocols supported, IP addresses, telephone numbers, routing information, and so on. Together this information constitutes a user profile that is stored in a file or database on the

RADIUS server.

In addition to authenticating dial-up users, RADIUS can be used as a generic authentication protocol.

The RADIUS protocol is very flexible, and servers are available for most operating systems, including Microsoft Windows NT/2000. The

67


RADIUS implementation on this security system allows you to configure access rights on the basis of proxies and users.

Before you can use RADIUS authentication, you must have a functioning RADIUS server on the network. As passwords are transferred in clear text (unencrypted), we strongly recommend that the

RADIUS server be inside the network protected by the security system, and that the security system and server be on the same switch.

The following section details the setting up Microsoft IAS (RADIUS

Server for MS Windows NT and 2000). If you use a different server, you will need the following information to enable the operation of the security system together with the user authentication.

The authentication request comprises three set fields:

• Username

• Password in clear text (PAP)

• Type of proxy (the string http, smtp or socks) in the NAS-

Identifier field

Your RADIUS server should use this information to determine whether or not access should be granted, and should send back a properly formatted reply.

Configuring Microsoft’s IAS RADIUS Server:

IAS is a part of all versions of Microsoft Windows 2000 Server, but is generally not installed by default. For Microsoft Windows NT4, IAS is a part of the NT4 Option Pack and is available without charge. The

MS Windows NT4 IAS has fewer features than the 2000 version, but is nevertheless sufficient for user authentication with the security system.

1.

Check that the IAS service is installed. If it is not, install it now.

2.

Create a user group for every proxy to be used.

68


Tip:

Name the group according to the proxy to be used. For example, name the group for the HTTP Proxy HTTP Proxy

Users.

55.

56.

For each group, add the users who should be allowed to use this proxy service.

Make sure that the user flag Allow dial-in access to the

network is set for every user in these groups.

You can find this setting in the user properties dialog box. MS

Windows NT/2000 needs this flag to answer RADIUS inquiries.

57.

58.

Open the administration program for the IAS service.

Add a client. This requires the following information.

Client Name: Enter the DNS name of your security system here.

Protocol: Choose RADIUS.

IP Address of the Client: Enter the internal IP address of the security system.

Client Vendor: Choose RADIUS Standard.

Shared Secret: Enter a password here. You will need this password again when configuring the RADIUS server with Web-

Admin.

59.

Security Note:

For the

Shared Secret

only passwords consisting of alphanumeric

, minus (-), and period (.) characters are allowed. Other characters, for example %!#_{} are not allowed.

Now open the RAS rules menu.

A standard rule is listed here. If you intend to use IAS only with the security system, you can delete this entry.

69


60.

For every proxy, enter a rule. Choose a descriptive name, such as HTTP access.

Add two conditions:

1. Condition 1: The NAS Identifier field must correspond to a string from the following table.

Proxy Type NAS Identifier String

HTTP http

L2TP over IPSec l2tp

PPTP pptp

SOCKS socks

SMTP smtp

WebAdmin Access webadmin

Surf Protection “Profilname”

2. Condition: The Windows group of the user must match the group established in step 2.

Access is granted only when both conditions are met.

Edit the profile so that only an encrypted connection is allowed by disabling the No Encryption function in the

Encryption register.

61.

Edit the profile so that an unencrypted authentication is allowed by disabling the Encrypted Authentication (PAP) function in the Authentication register.

Leave the other values unchanged.

62.

63.

Open the WebAdmin configuration tool and open the User

Authentication menu in the System tab.

In the RADIUS Server Settings window, click the Enable button next to Status (the status light will show green).

70


64.

Address or

Hostname: Enter the

IP address or the host name of the RADIUS server.

Shared Secret: Enter the Shared Secret from step 6.


65.

66.

In the Proxies tab, open the menu corresponding to the proxy service you wish to use.

If User Authentication is not enabled (red status light), click the Enable button.

67.

Authentication Methods: Choose RADIUS from the selection field.

Now confirm your settings by clicking on the Add button.

The user authentication using RADIUS is now active.

The IAS service will log every access attempt in the Microsoft

Windows NT/2000 Event Log.

In order to prevent the Windows Event Log from overflowing, the security system stores RADIUS access information for five minutes.

This may mean that changes in the RADIUS database will not be reflected at the security system for a few minutes.

Attention:

The security system sends queries on UDP port 1812.

71


4.1.7.2.

SAM – NT/2000/XP

This authentication method uses an MS Windows NT/2000 Domain

Controller or standalone server. Many businesses already use MS

Windows NT/2000 networks based on ActiveDirectory.

The advantage of SAM is that it is very easy to configure if the network already has a Primary Domain Controller (PDC) or if a server with a user database is running.

The drawback, however, is that this system does not distinguish between different user groups. You can either allow all users in an

SAM database access to a proxy or none of them.

Configuring SAM – NT/2000/XP:

In order to use this authentication method, you will need to have a Microsoft Windows NT or

2000 server on your network that contains the user information. This can be either a

Primary Domain Controller (PDC) or a standalone server.

Note that Windows servers have a NetBIOS name (the NT/2000 server name) as well as an IP address.

1In the System tab, open the User Authentication menu.

68.

In the SAM (NT/2000/XP) Server Settings window, click the Enable button next to Status.

PDC Name: Enter the name of the Domain Controller in this entry field.

Since, beginning with Windows 2000, these names are also official DNS names, only names consisting of alphanumeric, minus (-), and period (.) characters are allowed.

Other characters, for example %!#_{} are not allowed.

PDC Address: Enter the IP address of the Domain Controller.

72


BDC Name: If you have a Backup Domain Controller, enter its name in this entry field. If you do not use a BDC, enter the name of the PDC here.

BDC Address: If you have a Backup Domain Controller, enter its

IP address here. If you do not use a BDC, enter the IP address of the PDC here.

NT4 Domain: Enter the name of your MS Windows NT/2000-

Domain.

Allowed characters are: Letters of the alphabet, hyphen (-), and underscore characters (_).

69.

Note:

This is not the Internet domain, as in Company.com, but rather a simple designator, e.g., Intranet. If you are using a standalone server rather than a Domain Controller, enter its NETBIOS name here. This corresponds to the PDC Name entry.

Confirm your settings by clicking Save.

Security Note:

For the

Shared Secret

only passwords consisting of alphanumeric

, minus (-), and period (.) characters are allowed. Other characters, for example %!#_{} are not allowed.

Security Note:

If you use SAM authentication, make sure to disable the Guest account on your Windows domain. Otherwise all username/ password combinations will be accepted as valid.

73


4.1.7.3.

Active Directory/NT Domain Membership

In this authentication method the NTLM protocol is used. NTLM stands for New Technology LAN Manager and is a further development of the LAN manager protocol LM for the user authentication in

Windows networks. The Challenge Response based NTLM protocol is by default contained in the MS Windows 2000, XP and 2003 Server operating systems. The Squid Proxy can authenticate users through this protocol.

With this authentication method a MS Windows NT/2000 Domain

Controller (DC) is used for the evaluation of requests. For further information on Domain Controller (DC) please, refer to the introduction of the User Authentication menu on page 66.

The authentication method with NTML next to RADIUS also supports remote authentications. The method with NTLM in comparison to

RADIUS offers the advantage that, due to the Single-Sign-Onmechanism, the user needn’t always log in to the Internet with his

User Name and Password.

The functioning of the domain-connection-method of NTML is completely different from the three other authentication methods on this security system. In MS Windows environments, the authentication with NTML is in general configured for clients, using the Internet

Explorer browser. However, also systems with clients that use the browsers Firefox or Mozilla (e.g. Mozilla 1.6) can be successfully operated.

Note:

In order for the domain joining process to work, one of the Domain

Controllers (DC) for this domain must be in the systems broadcast range. The authentication with NTLM can at present only be used for the HTTP proxy to perform Single-Sign-On for Internet Explorer clients!

The notion of Single Sign-On (SSO) is in general used for a unique, central sign-on of a user into an IT structure. This is very useful since

74

Using the Security System the user must enter his identification data only once and will then be authenticated for all centrally connected services. This allows for the implementation of a uniform user and rights structure in a company.

In the conception of a central and unique authentication that shall be based on existing infrastructures a series of requirements must be met:

• Central administration: user authentication data must be maintained on only single place only

• Simple use from the perspective of the user: data shall be consistent and not kept twice, i.e. only one password for all services

• Security: passwords shall not be readable for attackers

The advantage of the latter is that the data in the concept presented here are never transferred over networks without encryption and are subjected to a specific expiration period. This makes a Brute-Force attack against encrypted data almost impossible.

Configuring Active Directory/NT Domain Membership:

1In the System tab, open the User Authentication menu.

70.

In the Active Directory/NT Domain Membership (NT/

2000/XP) Server Settings window, click the Enable button next to Status.

Enabling the NTLM

Domain

Membership in the

Status line does not unregister the security system from the domain. This must be done on the domain controller.

Domain Member Status: Shows Joined domain „Domain-

Name“ when join was successful.

75


Domain: Enter the name of your MS Windows NT/2000-Domain.

Allowed characters are: Letters of the alphabet, hyphen (-), and underscore characters (_).

Note:

This is not the Internet domain, as in Company.com, but rather a simple designator, e.g., Intranet.

NetBIOS Hostname: Enter the NetBIOS hostname the security system should have in the domain. You can just invent a name.

It does not have any additional significance. However, to avoid inconsistencies, please choose a name that is not already used in your domain.

Attention:

Please make sure not to use hostnames that are used by other systems and especially not the hostname of the domain controller – it could demote the Domain Controller to a Member

Server!

71.

Account: Enter the account name that is allowed to join computers to a domain. Usually it is the Administrator. This name is only used for joining the domain and is not saved on the security system!

Password: Enter the password for the above account. This password is only used for joining the domain and is not saved on the security system!

Confirm your settings by clicking Save.

Once, the security system is successfully joined to the Domain, the confirmation will be displayed under Domain Member Status.

4.1.7.4.

LDAP Server

LDAP, the Lightweight Directory Access Protocol defines the way in which clients communicate with X.500-conforming directory

76

Using the Security System services. The protocol thus specifies the type of access to such a directory service.

The security system uses the LDAP protocol to authenticate users for several of its services. The security system allows or denies access on the basis of certain attributes or group memberships established on the LDAP server.

This system supports the Microsoft Active Directory and Novell

eDirectory LDAP servers as well as those based on the Open Source

OpenLDAP software.

Microsoft Active Directory is an indexing service designed especially for Windows NT/2000 networks, and allows the central management and organization of network resources. It allows users to access system resources after a single sign on to a central server, and offers administrators centrally organized management of users, regardless of network topology or protocols used.

In order to use this directory service, you will need an MS Windows

NT/2000 Domain Controller.

Novell eDirectory – Novell Directory Service 8 - is an X.500-based index service designed to manage users, access rights, and other network resources. eDirectory is available for Netware versions 5 and higher, MS Windows NT/2000, Linux, and Solaris.

The OpenLDAP Foundation, the group which manages the Open-

LDAP open source project, has released the Stand-Alone LDAP server, called SLAPD. OpenLDAP can also be used to build a networked directory service with various other LDAP servers: For instance, the iPlanet Directory Server from Sun Microsystems is based on OpenLDAP code and fully compatible.

77


User Authentication

LDAP uses the Distinguished Name (DN) of a user to identify him or her. This name must be unique within the directory.

Microsoft Active Directory (AD) and Novell eDirectory (NDS8) give every object a defined DN. This DN identifies the object uniquely in the AD index or NDS tree. This DN is composed of the Common

Name (CN) and Domain Component (DC).

Example: CN=Administrator, CN=Users, DC=example, DC=com

MS Active Directory also allows for user authentication by User

Principal Name (UPN). This name consists of the login name and

DNS name of the domain.

Example: [email protected]

OpenLDAP simply uses the Common Name (CN) to identify users.

Please make certain that every user has a unique CN.

Security Note:

User authentication with a stand-alone LDAP server involves sending passwords in clear text over the network. As these passwords are not encrypted, an attacker with access to the network may be able to intercept them.

Note:

User authentication with an LDAP Server requires that the DNS

Proxy on the Proxies/DNS menu be enabled.

78


Configuring the Microsoft Active Directory Server:

Make sure that there is a user configured on your LDAP server to have full read privileges for the directory. This will be the query user.

Security Note:

Make sure that the user has only read privileges.

Microsoft Active Directory (AD) can grant privileges on the basis of group memberships, or on the basis of particular user attributes. In most cases, it is easier to use the Member Of query type to authenticate by group.

The Directory can be extended by self-defined attributes. If you wish to authenticate on the basis of particular User Attributes, every user account in the directory must be edited to define access rights. This is done by setting a particular attribute for each user which either grants or denies access to a service.

The following example illustrates the configuration for a hypothetical small company

example.com:

The user John Smith is in the

Trainees directory.

DN: cn=john smith, ou=trainees, dc=example, dc=com.

LogonName: [email protected]

This user can use his LogonName and password to log on to services like the SOCKS Proxy. The security system checks the user’s DN and password. If there is only one DN that corresponds to [email protected], and if the supplied password is valid, the user will be allowed to use the SOCKS proxy.

79


If you wish to use Group Membership to control access rights, complete the following steps to configure the Microsoft Active

Directory:

Step 1 – Creating a Security Group: a. In the Microsoft Management Console, click the domain with the right mouse button.

72.

Example: Domain example.com

With the left mouse button, click New and then Group.

73.

A new window will open labeled New Object - Group.

Enter a unique name for the group in the Group name field.

74.

Example: socks_users for the SOCKS Proxy

Under Group type select Security.

75.

Save your settings by clicking OK.

You have now created a new Security Group named

socks_users.

Step 2 – Adding Users to the Group:

80


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81


76.

Example: John Smith in the Trainees directory.

Left click the Properties button.

77.

A window named Properties will open.

In the Properties window, select Member Of tab.

78.

Click Add to add the new group.

79.

The Select Groups window will open.

Now choose the Security Group you wish to add the user to.

80.

Example: socks_users

Save your changes by clicking OK.

81.

The new Security Group will be added in the Member Of window.


Now execute the settings on the Internet security system. The settings in the configuration tool WebAdmin are explained on page

88.

Microsoft Active Directory, self defined attributes:

User authentication with Microsoft Active Directory can also use user attributes to assign access rights. For large organizations, however, this can be time-consuming to configure.

82


Note:

According to the LDAP standard, each user attribute must have an associated object ID, or OID. Object ID numbers are designed to be unique across the entire Internet; in order to manage this, the

Internet Assigned Numbers Authority (IANA) has been charged with assigning OID prefixes to organizations.

If your organization does not yet have an official OID space, you can request an OID prefix from the IANA at www.iana.org. Once you have an OID space, you should consider how best to use it to describe your network structure. Remember that each user attribute will require a unique OID.

In order to configure user attributes, the Microsoft Management

Console must be used to modify the Active Directory Schema. In order to do this, you must first mark the schema as editable.

83


Step 1 – Enable Editing of the Active Directory Schema:

1In the Microsoft Management Console, right-click Active

Directory Schema.

2Use the left mouse button to click Operations Master.

82.

The Change Schema Master window will open.

Check the option The Schema may be modified on this

Domain Controller.

83.

Save your changes by clicking OK.

The Active Directory Schema can now be edited.

Step 2 – Add New Attributes:

1Under Active Directory Schema, right click Attribute.

2Use the left mouse button to click New.

3In the Create New Attribute window, define the new attribute.

84.

Common Name: Enter a CN for this attribute.

LDAP Display Name: Give the new attribute a clear label. The name of the service this attribute controls would be a good choice.

Example: Socks.

Unique X500 Object ID: Enter the OID for this attribute in the entry field.

Syntax: Choose Boolean.

Minimum: Leave this field blank.

Maximum: Leave this field blank.


84


Step 3 – Allocate a Class for the Attribute:

1Under Active Directory Schema, left-click Classes.

2Right-click Users.

85.

A window named User Properties will open.

Click the Attributes tab and make the following settings.

86.

Optional: Use the drop-down menu to select the attribute and click Add.


87.

88.

In the Microsoft Management Console, right-click Active

Directory Schema.

With the left mouse button, click Reload the Schema.

Step 4 – Setting the Attribute for Users:

1In the ADSI Edit window, right-click the user to edit.

89.

Example: John Smith in the Trainees directory.

Left click the Properties button.

90.


In the Properties window, click the Attributes tab.

91.

92.

Select which properties to view: Choose Both.

Select a property to view: Choose the attribute to set.

Example: Socks.

93.

Syntax: This value was set while creating the attribute and cannot be changed.

From step 2, this should be. Boolean.

Edit Attribute: You can use this field to set the value of the attribute. The possible values are TRUE and FALSE.

Value(s): The current value of the attribute is shown here.


85


Now make the settings on the Internet security system. The settings in the configuration tool WebAdmin are explained on page 88.

Configuring a Novell eDirectory Server:


Security Note:


In most cases, you should use the groupMembership query type with Novell eDirectory (NDS8), as this allows an existing user index to be easily extended for proxy rights.

The index can also be configured to use user-defined attributes, which must be manually set for each user in the index. If you wish to authenticate on the basis of particular User Attributes, every user account in the directory must be edited to define access rights. This is done by setting a particular attribute for each user which either grants or denies access to a service.

You will need Novell ConsoleOne to configure the eDirectory Server.

The configuration and management of the Novell eDirectory server is described in detail in the accompanying documentation. You can find these documents at: http://www.novell.com/documentation/lg/edir87/index.html

Then make the settings for the Internet security system. The settings in the configuration tool WebAdmin are explained on page 88.

86


Configuring the OpenLDAP Server:


Security Note:


With OpenLDAP, users are identified on the basis of their Common

Names (CN). Please make certain that every user has a unique CN.

Important Note:

With the installation of the software alle existing data will be deleted from the computer!

Because there are many different LDAP servers based on the

OpenLDAP code, it is impossible to describe them all here. For further information, please consult the documentation accompanying your LDAP server.

If you are using the SLAPD server from the OpenLDAP Foundation, the current documentation is available at:

http//www.openldap.org.

Configuring LDAP on your Security System:

Make sure that there is a user configured on your

LDAP server to have full read privileges for the directory. This will be the query user. this user as well as the IP address of your LDAP server in order to complete the configuration of the security system.

You will need the Distin-

guished Name (DN) of

87


Security Note:

Make sure that the user has only read privileges.

1.

2.

In the System tab, open the User Authentication menu.

In the LDAP Server Settings window, enable the system by clicking Enable next to Status.

LDAP Type: Choose the type of LDAP server to use.

The available choices are: Microsoft Active Directory, Novell

eDirectory and OpenLDAP.

Unique User Attribute: This attribute defines how users should be authenticated on the LDAP server. The attributes available here depend on the type of LDAP server you are configuring. If you wish to use a self-defined attribute for authentication, select

Selfdefined here.

With the Microsoft Active Directory server, you can also choose to authenticate by User Principle Name (UPN) or

saMAccountName.

88 authentication by the Common Name (CN), Surname (SN), and Unique Identifier (UID) attributes.

Attribute Name:

This entry field is only shown if you have selected to authenticate by a

Selfdefined attribute from the Unique User Attribute dropdown menu.

Enter the attribute to use for authentication here.

IP Address: Enter the IP address of the LDAP server.

TCP Port: Enter the TCP port of the LDAP service. By default, this is set to 389 (the standard port for LDAP).


Bind DN: The value to enter here depends on the type of LDAP server you are using.

1. Microsoft Active Directory

Microsoft Active Directory can use either the User Principal

Name (UPN) or the full Distinguished Name (DN) of the user.

Examples:

UPN: [email protected]

DN: cn=administrator, cn=users, dc=example, dc=com

2. Novell eDirectory

Enter the full Distinguished Name (DN) of the user.

Example:

DN: cn=administrator, o=our_organisation

3. OpenLDAP

OpenLDAP and OpenLDAP-conforming servers can only use the

Distinguished Name (DN) of users.

Base DN: Enter the object name to be used as the basis for all client actions.

Examples:

For MS Active Directory: dc=example, dc=com

For Novel eDirectory: o=our_organisation

89


94.

95.

Enter the password in the Password entry field. This password should also be used for the Administration of the

Stand-alone-LDAP-Server.

Security Note:



Security Note:

As long as the LDAP authentication by attribute function is disabled, all users who are listed in the directory with a unique DN and a valid password can use the HTTP,

SMTP and SOCKS proxies, and can also access the

WebAdmin tool.

Advanced Authentication with LDAP:

1Enable the LDAP authentication by attribute function by clicking

Enable next to Status.

2Use the Service drop-down menu to select a service.

96.

The available services are: HTTP, SMTP, SOCKS and Web-

Admin.

In the Attribute Name field, enter the name of the attribute.

If you are using authentication using the MemberOf property on a Microsoft Active Directory Server, this should be the name of the Security Group to use.

Example: socks_users.

90


97.

In the Attribute Value field, enter the DN for the attribute.

The attribute value is the DN.

98.

Microsoft Active

Directory displays the

DN of attributes in the

Management Console, under ADSI Edit:

Here, under the Base

DN (example: dc=example, dc= com), find the attribute name

(example: socks _users) and right-click it. A window labeled CN=socks_users Properties will open.

Use the Select which properties to view drop-down menu to choose Both, and in the Select a property to view drop-down menu, choose distinguishedName. The DN for this attribute will be shown in Value(s).


Every member defined as a MemberOf the security group

socks_users will be allowed to use this service.

91


4.1.8.

WebAdmin Settings

Configure the access to the WebAdmin configuration tool in this menu.

General Settings

Language: In this dropdown menu you can determine the language.

Timeout (seconds): In this entry field enter the intervals in seconds, in which WebAdmin automatically logs you out, if there are no actions. By default, the system is set to 300 seconds after the installation. The smallest possible interval amounts to 60 seconds.


If you close your browser with an open WebAdmin session without closing WebAdmin through Exit, the last session remains active until the end of the time-out.

TCP Port: If you want to use the standard port 443 for the HTTPS service for another purpose (such as a deviation with DNAT), you must enter another TCP Port for the WebAdmin Interface here.

Possible values are 1024-65535, while certain ports are reserved for other services. In order to address WebAdmin after a modification, you must separately link the port through a colon to the IP address of the Internet security system, e.g.: https://192.168.0.1 :1443.

92


Access and Authentication

Allowed Networks: Add those networks to the selection field that are authorised to access Web- smooth installation. In this case and if the password is available, WebAdmin can be accessed from everywhere.

Admin. As with SSH, Any is entered here for a

Security Note:

As soon as you can limit the access to the Internet security administration (for example your IP address in the local network), replace the Any entry in the Allowed Networks selection field through a smaller network.

The safest solution is, if only one administrator PC has access to the

Internet security system through HTTPS.

Networks can be defined in the Definitions/Networks menu.

Authentication Methods: Select the authentication method in the selection field. In order to give you access to the Internet security system through the configurations tool WebAdmin after the installation, the authentication method Local Users has already been defined here and the respective User hase been entered in the

Allowed Users selection menu.

Further available authentication methods are NT/2000/XP Server,

RADIUS Database and LDAP Server.

Local Users are administered in the Definitions/Users menu.

Allowed Users: By default this is set to the user admin.

Local users are defined in the Definitions/ Users menu.

Log Access Network Traffic: All connections to the WebAdmin configuration tool are logged to the Packet Filter Logs as Accept

93

Using the Security System rule. The Packet Filter Logs can be found in the Local Logs/

Browse menu. By default, this function is disabled.

Enable this function by clicking on the Enable button (status light on green).

Block Password Guessing

This function can be used to limit the number of attempts to log in to the

WebAdmin configuration tool. After a specific number of attempts, the access from this IP address will be denied for a given time span.

Configuring the Blocking Protection for Login Attempts:

1In the System tab, open the WebAdmin Settings menu.

2Make the following settings:

99.

After failed Attempts: Select the maximum allowable number of attempts in the drop-down menu.

Block IP for Period: Enter the time span for the blocking protection in the entry field.

Save your changes by clicking Save.

Now, the blocking protection is enabled. The Never block Networks window, allows you to exclude networks or hosts from the blocking protection.

94


4.1.9.

WebAdmin Site Certificate

Encryption systems are an important part of many modern security systems. They are used, for example, when transmitting confidential information over Virtual Private Networks (in chapter on page

280), in User Authentication and Up2Date Service or, to securely administer the security system over the network.

Certificates and Certificate Authorities (CA) are an essential part of modern cryptographic protocols, and help close the gaps left open by other systems. Public Key Algorithms offer a particularly elegant form of encryption. They do, however, presuppose that the public keys of all communications partners are known.

At this point, a third, trusted party is used to ensure the validity of public keys. The third party issues certificates guaranteeing the authenticity of these keys: this third party is called a Certificate

Authority (CA). A certificate is a record in a standardized format with the owner’s most important data - his name, and his public key and is signed with the private key of the CA. The format for these certificates is defined in the X.509 standard.

In a certificate, the CA certifies, with its own signature, that the public key belongs to the person (or entity) it says it does. As the certificate contains information such as the name of the owner, duration of validity, issuing authority, and the signature of the CA, it can be seen as a kind of digital passport.

The WebAdmin Site Certi-

ficate menu allows you to create two certificates: first a CA certificate, which will be installed in your browser, and second the server certificate (signed by the CA certificate) which the system uses to authenticate itself to your browser. These two certificates contain the company’s data and the system’s hostname.

95


Creating a Certificate for WebAdmin:

1Under the System tab, open the WebAdmin Site Certificate menu.

2In the Certificate Information menu, enter the appropriate information for your firm.

Country: Choose your country from the drop-down menu.

State: Choose the state or region where you are.

City: Enter the name of city.

Organization: Enter the company’s name.

Section: Enter the department.

E-Mail Address: Enter your e-mail address.

100.

In the field Firewall Hostname, enter the host name or IP address of the security system you use to access WebAdmin.

Example: If you access WebAdmin through the URL https://192.168.10.1, enter 192.168.10.1 here.

101.

Save your entries by clicking the Save button.

Installing a Certificate for WebAdmin:

1.

To install the CA Certificate in your browser, click Import

Certificate into Browser in the CA Certificate Installation window.

The next few steps depend on your browser. For example, with

Microsoft Internet Explorer, the File download dialog opens.

Save file to disk: This option allows you to save the certificate to a local disk before installing it.

Open the file from current position: This allows you to install the certificate directly. The Certificate window will open. These registers allow you to inspect the information contained in the certificate before installing it.

96


102.

Click the OK button to start the process.

Note:

Due to system time differences and timezone offsets, the generated certificate may not yet be valid. Many browsers wrongly report that such certificates have expired, however this is not the case and any generated certificates will become valid after a maximum of 12 hours.

97


4.1.10.

High Availability

The main cause for a Internet security system and/or a firewall failure is a hardware failure, such as a failure of the power supply, hard disk, or processor. The High Availability (HA) system allows you to use two security systems with identical hardware in parallel. Security system 1 runs in normal mode (Master). Security system 2 is in Hot-

Standby mode (Slave) and monitors the active system through Link

Beat via the data transfer connection. Security system 1 regularly sends Heart Beat requests through this connection, which are answered by system 2. If necessary, the security system 2 also receives updates through this data transfer connection so that, in the case of system failure on the primary, it can take over operations immediately.

The graphic shows a network architecture with a High Availability

(HA) system, to which an internal network and a DMZ is connected.

The installation instruction describes how to connect one private network to a HA system:

98


Hardware and Software Requirements

• A license with the High Availability option: the License Key must be imported to both security systems (Normal and Hot

Standby mode)!

For more information on Licensing, see chapter on page 44.

• 2 security systems with identical software version and hardware

• 2 additional Ethernet network cards for the data transfer line: for monitoring the Heart Beat requests two Ethernet network cards that support this function are necessary!

• 1 Ethernet crossover cable

• 1 serial interface cable (optional)

• 2 switches

Important Note:

The hardware components, supported by the Internet security system, e.g. for a monitoring through Heart Beat requests are listed under http://www.novell.com/documentation/nsma51 in the

Hardware Compatibility List for Novell Security Manager

powered by Astaro tab.

Important Note:

If you use a security system for the High-Availability-(HA) system that was already in use, ensure that you update the second security system to the same version as system 1 prior to the configuration.

99


Installing the High Availability System

This installation instruction describes the necessary settings for the connection of the High-Availability system to one internal network.

For this configuration you need three network cards on both security systems: One to the internal network (eth0), one to the Internet

(eth1) and one for the data transfer connection (eth2) between the two security systems. For each additional internal network (e.g. a

DMZ) another switch is required.

Preperation:

1Installing the Software on both Computers:

Install the software on both computers.

For a description of how to install the software please see chapter on page 16.

26.

Starting the WebAdmin Configuration Tool and Configuring the System Passwords:

Configure all necessary passwords on both security systems. If the High Availability system is configured and administered later with the Configuration Manager, you also have to configure the Configuration Manager user (wwwrun) password.

27.

Connecting the Hardware:

In order to connect the hardware components (system 1 and 2,

Switches etc.) as shown in the graphic you have to know which

Sys ID has been assigned to which network card on the respective security system.

The interfaces must be identically configured on both security systems. Network cards with the same Sys ID must be connected to the same network: The interface to the Sys ID

eth2 is used here for example as data transfer connection.

100


In order to determine the Sys ID assignment, open the Net-

work/Interfaces in the WebAdmin configuration tool.

All network cards installed to the security system are listed in the Hardware Device Overview table.

If the network cards are from diverse producers and/or of another type you can read the Sys ID assignment here and identify the hardware correspondingly. If these are the same network cards proceed as follows:

The internal network card (eth0) was already configured during the installation of the software. In order to assign the Sys ID to the other network cards, set-up all network cards as Standard-

Ethernet network cards, with the exception of the Interface for

the data transfer connection (e.g. Sys ID eth2).

Important Note:

The network card for the data transfer connection mustn’t be configured in the Network/Interfaces menu. This interface is set-up later in the System/High Availability menu. For the monitoring via Heart Beat request reserve a network card that supports this function.

Now, successively connect your client to the network cards of the security system and execute the ping order. With the help of the corresponding IP-address you can then assign the respective Sys

ID.

Please, see page 138 for a description of how to execute a ping command.

Then shut down both security systems and connect the hardware components as shown in the graphic on page 98.

101


28.

Configuring System 1 (Normal Mode):

In the System tab, open the High Availability menu.

Click the Enable button next to Status to enable the option.

Device Name: Enter a descriptive name for the device here.

This name allows you to know which of both systems is running in normal mode. This device name can be up to 11 characters long.

Encryption Key: Enter the password in this entry field.

Security Note:


Network Interface Card: Select a network card to be used for the data transfer connection (example: eth2). You can only select those network cards that have not been configured before in the Network/Interfaces menu.

Important Note:

The network cards must have the same Sys ID (e.g., eth 2) on both systems. If you wish to use Heart Beat monitoring, use this menu to choose network cards on both the normal and standby systems which support this function.

Device IP: Assign an IP address from a Class-C-network to each security system within the HA device group. The IPs must be within an address range and may only be used once within a given device group. Example: The Device IP 10.0.14.1 is assigned to the Internet security system 1 and the Device IP

10.0.14.2 to security system 2.

102


Note:

The data transfer connection must only use a Class C network – that is a network with mask 255.255.255.0. The bitmask form cannot be entered here. The network defined for the data transfer cannot be used anywhere else.

Serial Interface (optional): In addition to watching the data transfer connection, the standby system can monitor the active system through the serial interface. No data is transferred over this connection. Select the appropriate serial interface from the drop-down menu.

Note:

When you save the settings as described in the following, the system will shut down and reboot immediately.

Save your changes by clicking on the Save button.

System 1 will now restart. If a keyboard is connected, the Num

Lock LED will blink on the keyboard.

When the system gets into the Hot-Standby mode, the system will beep twice and the LED will stop blinking. Because system 2 is still disabled, system 1 will boot normally into normal mode, and the Num Lock light will blink again.

After system 1 completes the boot process, the Num Lock light will stop blinking, and the system will beep five times in second cycles: this signals that the middleware has successfully loaded and initialized all services, rules, and processes.

Note:

If the beeps are not heard, and the LED light continues to blink, the middleware was unable to initialize all services, rules, and processes. If this happens, please contact the service department of your security solution supplier.

29.

Configuring System 2 (Hot Standby Mode):

103


Start system 2 and also execute step on system 2 and then click the Save button to confirm.

System 2 will now restart. If a keyboard is connected, the Num

Lock LED will blink.

When the system reaches the Hot Standby mode, the system will beep twice and the LED will stop blinking. System 2 recognizes system 1 through the data transfer connection, and remains in

Hot-Standby Mode.

Das High Availability system is now active.

The Internet security system in the Hot-Standby mode will be updated at regular intervals over the data transfer connection. Should the active system encounter an error, the second system will immediately and automatically change to normal mode and take over the system’s functions.

104


4.1.11.

Shut down/Restart

Restart will shut the system down completely and reboot. Depending on your hardware and configuration, a complete Restart can take up to 5 minutes.

Restart:

1Under the System tab, open the Shut down/Restart menu.

2In the action drop-down menu, choose Restart.

3Begin the reboot by clicking Start.

4When asked Do you really want to restart?, click OK.

The action Shut down allows you to shut the system down, and allows you to cleanly stop all running services.

For systems without a monitor or LCD display, the end of the shut down process is signaled by an unending series of beeps at onesecond intervals.

Depending on your hardware and configuration, this process can take up to 5 minutes. Only after the system has completely shut down, signaled by the Power down message, should you turn off the power. If the system is turned off without being shut down properly, the system must check the consistency of the file system: this means that the next boot will take longer. In the worst case, data may be lost.

The system will beep five times in a row to signal a successful startup.

Shut down:

1Under the System tab, open the Shut down/Restart menu.

2In the Action drop-down menu, choose the Shut down action.

3Begin the shutdown by clicking Start.

4When asked Do you really want to shut down?, click OK.

4.2. Networks and Services (Definitions)

105


The Definitions tab allows you to define networks and services for all of the other configuration menus (e.g., the packet filter, VPN, proxies, etc.) in one central location. This allows you to work with the names you define, rather than struggling with addresses, ports, and network masks. Another advantage is, that you can group individual networks and services together and configure them all at once. If, at a later date, you assign certain settings to these groups, they will apply to all networks and services contained therein. It is even possible to make groups of groups. Local users for the proxy services can also be defined here.

4.2.1.

Networks

In the Networks menu, the hosts and networks and also the network groups are defined.

The network table contains static networks which have been pre-defined. By default, the table contains next to the definitions for the internal network card eth0 additional statically entered networks. These statical networks cannot be edited or removed. The hosts and networks can be grouped together. These groups will be treated as individual hosts and networks and can belong to an upstream group.

The network types are represented by symbols.

The following pages contain a description of the different network types available and of how they are defined.

106


The network types are represented by symbols:

The Symbols

Icon Column Display/Setting

Network type Interface

Network type Host/Server

Network type Network

Network type

Network type

Network type

Network group

DNS server

IPSec user group

Adding Host:

1Under the Definitions tab, open the Networks menu.

2Click on the New Definition button.

3The entry window will open.

103.

Make the following settings:

Name: In the entry field, enter a unique host name.

This name will be used later, for example to configure packet filter rules. Allowed characters are: The only allowed characters are alphanumeric characters, minus (-), space ( ), and underscore (_). Names may be up to 39 characters long.

Type: Select Host from the drop-down menu.

Address: Enter the IP address in the entry field.

Comment: You can enter a host description in this entry field.

104.

Save the host by clicking on the Add Definition button.

If the definition is successful, the new Host will be entered in the network table. You will now find this host under its name also in different other menus. You could, for example define this host under

System/Remote Syslog as Remote Syslog Server.

107


Adding Network:


2Click on the New Definition button.

The entry window will open.

105.


Name: In the entry field, enter a network name.


Type: Select Network from the drop-down menu.

Address/Netmask: Enter the IP address in the entry field and select the network mask from the drop-down menu.

Comment: You can enter a network description in this entry field.

106.

Save the network by clicking on the Add Definition button.

WebAdmin will check that your entries are valid.

After successful definition, the new network will appear in the network table. The network name will also be available for use in various configuration menus.

Using the network name you can, for instance, enable HTTP proxy access for the new network under Proxies/HTTP.

108


Adding DNS Server:




107.


Name: In the entry field, enter a unique DNS Server name.


Type: Select DNS Hostname from the drop-down menu.

Hostname: Enter the hostname in this entry field.

Comment: You can enter a DNS Server description in this entry field.

108.

Save the host by clicking on the Add Definition button.

If the definition is successful, the new Host will be entered in the network table. You will now find this host under its name also in different other menus.

Defining Network Group:




109.


Name: In the entry field, enter a unique network group name.


Type: Select Network Group from the drop-down menu.

109


Initial Members: From the selection field, select the network card by pressing the Ctrl-key on the keyboard and selecting the name with the mouse.

Comment: You can enter a network group description in this entry field.

110.

Save the network group by clicking on the Add Definition button.

After successful definition, the new network group will appear in the network table. The network group name will also be available for use in various configuration menus.

Defining IPSec user group:

This definition contains only the Distinguished Name (DN). It is used for incoming IPSec connections, using X.509 certificates. If the

DN of the group corresponds to the one of the user, his virtual IP address will dynamically be added to the group.




111.


Name: In the entry field, enter a unique name for the IPsec user group.


Type: Select IPsec User Group from the drop-down menu.

DN Template: For the VPN-ID-Type Distinguished Name you will need the following data from the X.509 tab tree: Country

(C), State (ST), Local (L), Organization (O), Unit (OU) Common

110


Name (CN) and E-Mail Address (E).

The data must be listed in the same order as a certificate in this entry field.

Comment: You can enter a IPsec user group description in this entry field.

112.

Save the IPsec user group by clicking on the Add Definition button.

After successful definition, the new IPSec user group will appear in the network table. The IPSec user group name will also be available for use in various configuration menus.

Filters

The Filters function allows you to filter networks or hosts with specific attributes from the table. This function considerably enhances the management of huge networks, as networks of a certain type can be presented in a concise way.

Filtering networks:

1Click on the Filters button.


113.

Enter the filter attributes in the fields listed. You don’t have to define all attributes.

Name: If you want to filter the networks by names, enter the expression in the entry menu.

Type: Use this drop-down menu to filter the networks of a specific type.

Address Values: If you wish to filter networks by specific addresses, enter the IP address in this entry field.

111


114.

To start the filter, click on the Apply Filters button.

Only the filtered networks will be displayed in the table. Next time when you open the menu, the complete network table will be displayed.

Further Functions

Editing Definitions: Click on the settings in the Name, Value and

Comment columns in order to open an editing window. You can then edit the entries.

Deleting Definitions: Clicking on the symbol of the trash will delete the definition from the table.

112


4.2.2.

Services

The Services menu is used to define the Services and Service Groups.

Services define certain types of traffic over networks like the Internet. A service is defined by a

name, a protocol, and

ports.

The following protocols can be used: TCP, UDP, TCP/

UDP, ICMP, ESP, AH and

IP.

UDP uses port numbers between 0 and 65535 (inclusive) and is a stateless protocol that uses no so-called ACK-Bit. Because it does not keep state, UDP can be faster than TCP, especially when sending small amounts of data. This statelessness, however, also means that

UDP cannot recognize when packets are lost or dropped. The receiving computer does not signal the sender when it receives packets successfully.

TCP connections also use port numbers from 0 to 65535 (inclusive).

Lost packets can be recognized through TCP and be requested again.

in a TCP connection, the receiver notifies the sender when a packet is successfully received (connection related protocol). TCP sessions begin with a three way handshake and are torn-down at the close of the session.

The ESP and AH protocols are used for Virtual Private Networking

(VPN). These protocols are covered in chapter on page 280.

The network table contains the defined services and groups. By

Default, the table contains the already pre-defined statically entered services.

113


Services can be grouped into Service Groups. These service groups can be used the same way single services can, and can themselves be included in other service groups. In the service table service groups are labeled by the group symbol ( ).

The definition of Service Groups is described on page 115.

Add Service:

1Under the Definitions tab, open the Service menu.



115.


Name: In the entry field, enter a unique Service name.


Type: Select Service from the drop-down menu.

Protocol: Select the Protocol from the drop-down menu.

Source/Destination Ports: In the left entry menu, enter the

Source Port, that is the Client Side of the service. In the right entry menu, enter the Destination Port, that is the Server Side of the service.

116.

The other settings depend on the selected protocol:

For the TCP and UDP protocols you need the following two values. Entry options: A single port (e.g., 80) or a port range

(e.g., 1024:64000).

Source/Destination Ports: In the left-hand entry menu, enter the Source Port, i.e. the Client Side of the service. In the right hand entry menu, enter the Destination Port, i.e. the Server Side of the service.

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The ESP and AH protocols are used for IPsec VPN connections.

The port entered here should be agreed upon with the remote end of the IPSec VPN tunnel.

SPI: Enter a value from 256 to 65535. Values up to and including

255 are reserved by the Internet Assigned Numbers

Authority (IANA).

For the ICMP protocol, select a type of ICMP packet from the

ICMP type drop-down menu.

For the IP protocol enter the protocol number into the Protocol

Number entry field.

Comment: You can enter a service description in this entry field.

117.

Save the Services by clicking on the Add Definition button.

After successful definition, the new service will appear in the service table.

Defining Service Group:

1Under the Definitions tab, open the Service menu.



118.


Name: In the entry field, enter a unique Service Group name.


Type: Select Service Group from the drop-down menu.

Initial Members: From the selection field, select the services by pressing the Ctrl-key on the keyboard and selecting the name with the mouse.

119.

Save the Service Group by clicking on the Add Definition button.

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After successful definition, the new service group will appear in the service table.

Filters

The Filters function allows you to filter Services with specific attributes from the table. This function considerably enhances the management of networks with many services, as services of a certain type can be presented in a concise way.

Filtering services:



120.


Name: If you want to filter the services by names, enter the expression in the entry menu.

Protocol: This drop-down menu allows you to filter the services by specific protocols.

Source Port: If you want to filter services by a specific source port, enter it in this entry field.

Destination Port: If you want to filter services by a specific target port, enter it in this entry field.

Comment: If you want to filter services by specific comments, enter the expressions in this entry field.

121.


Only the filtered services will be displayed in the table. Next time when you open the menu, the complete service table will be displayed.

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Editing Definitions: Click on the settings in the Name, Value and

Comment columns in order to open an editing window. You can then edit the entries.

Deleting Definitions: Clicking on the symbol of the trash will delete the definition from the table.

4.2.3.

Users

In the Users menu Local

Users are added, if the use of proxy services should be limited to sepcial persons.

This is an alternative to using an external user database. This menu allows you to define which user has access to which proxy services. Available options are

HTTP-Proxy, SMTP-Proxy, SOCKS-Proxy, WebAdmin, L2TP over

IPSec and PPTP (Remote Access).

Security Note:

Normally, only the admin user has access to WebAdmin. The password to WebAdmin should be changed at regular intervals.

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Add Local Users:

1Under the Definitions tab, open the Users menu.



122.


Username: In the entry field, enter a unique username for the local user.

This username will be used later, for example to configure packet filter rules. Allowed characters are: The only allowed characters are alphanumeric characters, minus (-), space ( ), and underscore (_). Names may be up to 39 characters long.

Password: Enter a password here.

Security Note:


Comment: You can enter a local user description in this entry field.

123.

Save the Local User by clicking on the Add Definition button.

The new User will then be displayed in the table.

124.

In the table, enable the services for the Local User.

At the beginning, no services are enabled for the user. Enable the services, by clicking on the corresponding term.

Example:

HTTP = the HTTP Proxy is not enabled

HTTP = the HTTP Proxy is enabled

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The available services are: HTTP Proxy, SMTP Proxy, SOCKS

Proxy, WebAdmin, L2TP over IPSec and PPTP (Remote

Access).

PPTP Address: In PPTP connections also a static IP address can be assigned to a remote host instead of a dynamic address from a PPTP IP pool. In order to define a static IP, click on the field in the PPTP Address column and enter the address in the entry field.

Click the Save button to save your changes. In order to interrupt this process, click on the Cancel button.

For more information on PPTP VPN Access, please refer to chapter on page 180.

Filters

The Filters function allows you to filter Users with specific attributes from the table.

This function considerably enhances the management of huge network configurations, as users of a certain type can be presented in a concise way.

Filtering users:



125.


Username: If you want to filter the users by username, enter the expression in the entry field.

Comment: If you want to filter users by specific comments, enter the expressions in this entry field.

126.


119


Only the filtered users will be displayed in the table. Next time when you open the menu, the complete user table will be displayed.


Editing Local Users: Click on the settings in the Name, Password,

PPTP Address and Comment columns in order to open an editing window. You can then edit the entries.

Deleting Local Users: Clicking on the symbol of the trash can will delete the definition from the table.

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4.3. Network Settings (Network)

The Network tab contains menus which allow you to configure net-

work cards and virtual interfaces, as well as to perform networkspecific configuration and management tasks.

4.3.1.

Hostname/DynDNS

Firewall Hostname

Hostname: Enter the hostname for the security system in this entry field. Example: firewall.mydomain.com

A Hostname or domain name may contain alphanumeric, period and minus characters. At the end there must be an alphabetic designator, such as „com“, „de“ or „org“. The Hostname will appear in the subject line of all Notification E-Mails.

Save your entries by clicking the Save button.

Note:

The Hostname will appear in the subject line of all Notification E-

Mails to the Administrator.

Dynamic DNS

Dynamic DNS addresses a device or a VPN receiver through a DNS decryptable applicable IP address is stored for each name to a public DNS server in the Internet at each connection. The device can always be reached through this name - as long as it online, at least. A mobile user, for example can access his company network through Dynamic DNS, even if the company only

121

Using the Security System uses standard DSL connections with dynamic IP addresses. In addition to VPN applications, Dynamic DNS can also be used for remote maintenance and control.

Defining Dynamic DNS Servers:

1In the Network tab, open the Hostname/DynDNS menu.

2Enable the function by clicking on the Enable button in the Status column.


127.


Hostname: In the entry field, enter the hostname.

Username: In the entry field, enter the username.

Password: In the entry field, enter the password.

128.

Save your settings by clicking on the Save button.

4.3.2.

Interfaces

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A firewall requires at least two network cards in order to securely connect an internal network (LAN) to an external one (the Internet).

In our examples, the Net-

work card eth0 is always the interface connected to the internal network. Net-

work card eth1 is the interface connected to the external network (e.g., to the Internet). These interfaces are also called the trusted and untrusted interfaces, respectively.

Network cards are automatically recognized during the installation: if new network cards are added later, a new installation will be necessary. In order to re-install the system, simply make a backup of your configuration, install a new copy of the software, and re-load your backed-up configuration.

As is shown in the graphic at left, the firewall must be the only point of contact between internal networks and external ones. All data must pass through the security system.

We strongly recommend against connecting both internal and external interfaces to one hub or switch – except if the switch is configured as a VLAN switch. There might be wrong ARP resolutions (Address Resolution

Protocol) (ARP clash), which cannot be administered by all operating systems (such as those from Microsoft).

Therefore, one physical network segment has to be used for each firewall network interface.

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Using the Security System configure and manage installed on the also all interfaces with

(Internet) and internal networks (LAN, allows you to all network cards the external network

DMZ).

Note:

While planning your network topology and configuring the security system, take care to note which interface is connected to which network. In most configurations, the network interface with SysID

eth1 is chosen as the connection to the external network.

In order to install the High Availability (HA) system, the selected network cards on both systems must have the same SysID. Installing the HA system is described in more detail in chapter on page 98.

The following sections explain how to use the Current Interface

Status and Hardware List windows to manage the various Inter-

face types.

Current Interface Status

This window allows you to configure both, logical and virtual

interfaces. The table lists all interfaces which have already been configured. The graphic at left shows the

Interfaces menu after three Ethernet network cards have been configured.

During the installation, you will have configured the eth0 interface.

This interface is the connection between the security system and the

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Using the Security System internal network (LAN). By default, this network card is named

Internal. The table displays all of the most important information about the interfaces: the administrative status (enabled/disabled, indicated by a green or red status light), current connection status

(Up/Down), Name (Name), ID (Sys ID), network card type (eth/

wlan) as well as IP address and network mask (Parameters).

Click the status light in the Admin column to administratively enable or disable the interface. The functions in the Actions column allow you to edit the configuration of the interface, or to delete it entirely.

With this Internet security system, you assign one Name and also a specific network card to one virtual interface. Three logical networks will then be defined for each configured interface:

• An interface (NAME (Address)), consisting of the defined IP address and the network mask 255.255.255.255 (Host)

• An interface (NAME (Network)), consisting of the defined IP address and the network mask 255.255.255.255 (Network)

• A Broadcast (NAME (Broadcast)) network, consisting of the broadcast IP for this interface and the network mask

255.255.255.255 (Host)

The networks are shown in the Networks menu. If an interface is configured using a dynamic addressing scheme, for example through

DHCP or PPPoE, these settings are automatically updated. This means that all functions (for example, packet filter rules) configured with these aliases will automatically use the correct addresses.

Hardware List

This table lists all network cards and serial interfaces installed on the security system, together with the relevant hardware information. The table shows, for example, the system-assigned ID (Sys ID),

125

Using the Security System type of network card, hardware (MAC) address (Name/Parame-

ters), and PCI bus information: Bus/Device/Function (PCI Device

ID).

PPP modems, which are based on the serial console can be connected to the serial interface. For more information on configuring the serial interface with a PPP modem, please see chapter on page 160.

Error:

The Hardware List table doesn’t list all of the network cards.

Possible Causes:

The missing network cards were added after the installation of the security system, or were not recognized during installation. Please contact the support department of your security system provider.

Attention:

If you change the IP Address of the internal network card (eth0), you may lock yourself out.

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4.3.2.1.

Standard Ethernet Interface

To configure a network card for a standard Ethernet connection to an internal or external network, you must configure the card with an IP address and netmask.

All network cards installed on the security system are shown in the Hardware

List.

Configuring a Standard

Ethernet Connection:

1In the Network tab, open the Interfaces menu.

2Click on the New button.

The Add Interface window will open.

129.

In the Name entry field, enter a descriptive name for the interface. (example: Externally for an Internet connection)

130.

Use the Hardware drop-down menu to select a network card.

Tip:

For an external connection (e.g., to the Internet) choose the card with Sys ID eth1.

131.

Use the drop-down menu Type to select Standard Ethernet

Interface.

Please note that one network card cannot be used as both a

Standard ethernet interface and a PPP over Ethernet

(PPPoE-DSL) or PPPTP over Ethernet (PPPoA-DSL) con-

nection simultaneously.

132.

Now make the specific settings for this interface type:

127


128

Address: If you wish to use a static IP address for this interface, select Static from the drop-down menu and enter the address to use in the entry field. If you wish to have a gateway dynamically assigned via DHCP, select Assign by DHCP from the drop-down menu.

Important Note:

If you wish to configure the Uplink Failover on Interface function, observe the description of this function while entering the network!

Netmask: If you wish to use a statically defined network mask for this interface, use the drop-down menu to select Static and enter the netmask to use in the entry field. If you wish to have a netmask dynamically assigned via DHCP, select Assign by

DHCP from the drop-down menu.

Default Gateway: If you wish to use a statically defined default gateway, use the drop-down menu to select Static and enter the address of the gateway in the entry field. If you wish to have a gateway dynamically assigned via DHCP, select Assign by

DHCP from the drop-down menu. Otherwise, select None.

Proxy ARP: When this function is enabled, the security system will answer ARP requests on the selected interface for all known networks. This system will thus act as a proxy on this interface for all of the other directly-connected networks.

This function is only required in special cases, for example when an attached network cannot be configured with normal routing entries (e.g., when the network includes a router over which you have no control).

By default, the Proxy ARP function is disabled (Off). To enable it, select On from the drop-down menu.

Uplink Failover on Interface: This function will only displayed, if the parameter Assign by DHCP or Static has been selected in the Default Gateway drop-down menu.


If a network card is an interface to the Internet (e.g., 2 Megabit fixed connection) you can configure a standby connection by a second Internet access (e.g., DSL connection) and an additional network card. If the primary connection fails, the uplink will automatically be set up through the backup Internet access. In order to monitor the connection, the Primary Interface sends four ping requests to the Uplink Failover check IP every five seconds. Only if all four ping requests are not replied to, the

Backup Interface is loaded.

When the Internet connection is established via the Backup

Interface the ping requests are still sent by the Primary Inter-

face. As soon as the security system receives the corresponding reply packages to the ping requests again, the Internet connection is again established by the Primary Interface.

Important Note:

When the Uplink Failover on Interface function is used, two different networks must be defined on the Primary and Backup

Interface. Therefore you need two separate Internet accesses next to the additional network card.

Uplink Failover on Interface is by default disabled (Off). If you wish to use this network card as primary Internet connection, then configure it in the Primary Interface drop-down menu. If this network card shall contain the standby connection, select the setting Backup Interface.

Uplink Failover check IP: This entry field will be displayed if the Primary Interface setting has been selected for the Uplink

Failover on Interface function. Enter the IP address of a host here, which replies to the ICMP Ping requests and which, in addition to that, is always reachable! The security system will send ping requests to this host: if no answer is received, the backup interface will be enabled by the failover. In this entry field, there must always be an IP address for the failover!

129


130

Monitor Interface Usage: This function monitors the bandwidth on the interface. Once, the bandwidth falls short of or exceeds a specific value, a notification e-mail will be sent to the administrator.

The maximum available bandwidth must be entered for the

Monitor Interface Usage function into the Uplink Bandwidth

(kbits) and Downlink Bandwidth (kbits) entry fields. The notification e-mail to the administrator will be sent, as soon as the actually available bandwidth falls off or exceeds a predefined limit value. The limit values are configured with the Notify dropdown menus.

The settings will only be displayed once the Monitor Interface

Usage function is enabled (On).

QoS Status: In order to use Quality of Service (QoS) bandwidth management on an interface, enable this option. To enable the Quality of Service (QoS) function, select On from the drop-down menu.

Important Note:

For the bandwidth management Quality of Service (QoS) you must define the values for Uplink Bandwidth (kbits) and

Downlink Bandwidth (kbits). These values are used as basis for the bandwidth management system: incorrect values can lead to poor management of the data flow. The Quality of

Service (QoS) function is described in chapter .

Uplink Bandwidth (kbits): This setting will only appear, if the

QoS or Monitor Interface Usage function is enabled. In this entry menu, enter the available bandwidth for the Uplink in full kilobits. This value can be determined either from the values of the upstream interface or from the router. On an interface to the

Internet, this value corresponds to the bandwidth of the Internet connection - on an ADSL access the Uplink bandwidth amounts

Using the Security System to 128 kBit/s and on a 2-Megabit fixed connection to 2048 kBit/s.

Downlink Bandwidth (kbits): This setting will only appear, if the QoS or Monitor Interface Usage function is enabled. In this entry menu, enter the available bandwidth for the Downlink in full kilobits. On an interface to the Internet, this value corresponds to the bandwidth of the Internet connection - on an

ADSL access the Downlink bandwidth amounts to 768 kBit/s and on a 2-Megabit fixed connection to 2048 kBit/s.

Notify when uplink usage below (%): This setting will only be displayed, when the Monitor Interface Usage function is enabled. Use the drop-down menu to configure the lower threshold for the uplink.

Notify when uplink usage exceeds (%): This setting will only be displayed, when the Monitor Interface Usage function is enabled. Use the drop-down menu to configure the upper threshold for the uplink.

Notify when downlink usage below (%): This setting will only be displayed, when the Monitor Interface Usage function is enabled. Use the drop-down menu to configure the lower threshold for the downlink.

Notify when downlink usage exceeds (%): This setting will only be displayed, when the Monitor Interface Usage function is enabled. Use the drop-down menu to configure the upper value for the downlink.

MTU Size: The MTU is the size (in bytes) of the largest transmittable packet. MTU stands for Maximum Transfer Unit. For connections, using the TCP/IP protocol, the data will be grouped into packets. A maximum size will be defined for these packets.

Packets larger than this value will be considered too long for the connection and fragmented into smaller ones before transmission. These data packets will be sent again. However, the per-

131

Using the Security System formance can be limited, if the upper value is too low.

The largest possible MTU for an Ethernet interface is 1500 Bytes.

The following value is the default for the Standard Ethernet

Interface: 1500 Byte.

133.

Confirm these settings by clicking Add.

The system will now check the address and network mask for semantic validity. After a successful check, the new interface will appear in the Current Interface Status table. The interface is not yet enabled (status light is red).

134.

Enable the interface by clicking the status light.

The interface is now enabled (status light shows green). The

Oper column will at first show that the interface is Down: the system requires a short time to configure and load the settings.

135.

Click the Refresh button to load the menu again.

Further information about the Refresh function can be found in chapter on page 36.

When the message Up appears, the interface is fully operational. The network card settings are displayed in the Parameters column.

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4.3.2.2.

Additional Address on Ethernet Interface

One network card can be configured with multiple additional IP addresses (also called IP aliases). This function allows you to manage multiple logical networks on one physical network card. It can also be used to assign further addresses to a security system running NAT. NAT is described in further detail in chapter on page 168. Each network card can be configured with up to 255 additional addresses.

Adding additional addresses to a network card:




136.

In the Name entry field, enter a descriptive name for the interface.

137.


138.

Use the Type drop-down menu to select Additional address

on Ethernet interface.

139.

Now make the specific settings for this interface type:

Address: For this interface type, the address must be statically defined. This kind of interface can only use static addresses.

Netmask: This interface type requires a statically defined netmask. This kind of interface can only use static masks.

Default Gateway: If you wish to use a default gateway with this interface, select Static from the drop-down menu and enter the gateway address in the entry field. Otherwise, select None.

140.


133



141.




142.




134


4.3.2.3.

Wireless LAN

The industry standards IEEE 802.11 apply to Wireless LAN. This

Internet security system supports the IEEE 802.11b protocol. This standard uses radio signals in the ISM frequencies (in the 2.4 GHz band) to communicate between nodes. ISM stands for Industrial

Scientific and Medical. The ISM frequencies have been specifically allocated for unlicensed communication by industrial, scientific, and medical organizations, and are thus available for cost-free private use. The IEEE 802.11b standard allows for a maximum bandwidth of

11 Mbit/s. When planning your network design, however, please note that bandwidth actually available will be smaller when the distances between nodes are large.

Important Note:

In order to configure a Wireless LAN, you will need a PCMCIA card with a Prism2, Prism2,5- or Prism3-compatible chipset. The hardware supported by the security system is listed in the Hardware

Compatibility List for Novell Security Manager powered by

Astaro

nsma51.

The wireless LAN interface on the security system can be configured either as a Wireless LAN Access Point or a Wireless LAN Station.

The Wireless LAN Access Point mode connects wireless nodes with one another: its function is analogous to that of a hub in a traditional wired network. Wireless nodes can also communicate with the (wired)

LAN through the security system.

In the Wireless LAN Station mode, the security system functions as a normal node on an existing wireless network. Only in this mode can the system acquire an IP address through DHCP.

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Wireless LAN Security

The 802.11 standard includes the WEP standard for encrypting radio communications. WEP stands for Wired Equivalent Privacy. This encryption method is based on the RC4 cipher, and uses a secret string to encrypt and decrypt messages. Activating WEP requires this secret key to be configured on all interfaces on the wireless network.

All transmissions over the network are encrypted with this key at the sending station. and then decrypted at the receiving station. Without this key, the data cannot be decrypted.

This security system can also use WEP for Authentication. A computer attempting to connect to the network which is not configured with the correct key will be dropped at the access point.

The Wireless LAN Access Point mode also allows stations to be selectively granted access to the network on the basis of MAC Ad-

dress. Normally, in the interest of flexibility, a wireless LAN will allow any new node onto the network as long as it is configured with the correct WEP settings. An administrator may choose, however, to control which nodes should have access: Such a filter can be configured to allow only certain nodes – for instance, the one identified by MAC address 00:04:76:26:65:4C – onto the network. When a new node attempts to join the network, the security system will check its

MAC address: if the hardware address is in the list of allowed nodes, it will be permitted to join, otherwise the connection will be dropped.

This security system supports two kinds of MAC address filter:

negative and positive. A negative filter allows all hardware addresses to join the network except those on the list. In the access control you only define those network cards that should not have access to the Wireless LAN.

A positive filter, on the other hand, first of all excludes all MAC addresses. In the access control you define explicitly those network cards that are permitted to join the Wireless LAN.

136


Security Note:

If at all possible, a positive filter should be used, which is by far safer.

The following settings are required to configure a wireless LAN

PCMCIA card:

• SSID: An acronym for Service Set Identifier: this is essentially the name of the network. More than one wireless LAN can coexist in the same physical space provided that they have different names or use separate channels. The name of a network can be chosen freely: the only requirement is that it not contain any space characters.

If you are configuring a Wireless LAN Station interface to connect to an already-existing wireless network, this must be the name of that network. The name can be up to 32 characters long.

• Channel: This system must be manually configured with the radio channel to use. If other wireless networks are in the area, you should chose an unused channel for your network.

Please also note that only certain channels may be used in certain countries:

Country

USA & Canada

Europe (ETSI)

Japan

Channel

1 to 11

1 to 14

1 to 14

Country

Spain

France

Channel

10/11

1 to 13

• WEP: In order to use WEP encryption, you will need at least one

WEP key - up to four can be used. You can choose between a 40 bit and 104 bit keys. A 40-bit key requires 5 hexadecimal numbers, while a 104-bit key requires 13 numbers. Please note that a hexadecimal number is two characters, each either a number (0-

9) or a letter (A-F).

Example of a 40-bit key: 17:A5:6B:45:23

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• Access Mode (only for Wireless LAN Access Point mode): If you wish to use the MAC address filter, you must compile a list of the

MAC addresses which are explicitly allowed to connect to the network (positive filter), or which are explicitly not allowed to

(negative filter).

How to determine the MAC address of a computer is described in the next section.

Determining the MAC address:

If you have not yet installed your network card, you can simply examine it to determine its MAC address: the unique MAC address is usually printed on the card itself.

If the wireless LAN is already being used and you wish to install a new

MAC filter, you can use the following commands on the mobile nodes to determine the MAC address. If you are configuring a small wireless

LAN, the mobile computers are MS Windows computers, and you have physical access to them, follow these steps:

1Open the Command Prompt.

2The Command Prompt can be found in the Start menu, under

Programs/Accessories/Command Prompt.

143.

Enter the following command at the prompt: ipconfig –all

144.

Press the Enter key.

The Physical Address row contains the MAC address, for example 00-04-76-26-65-4C.

145.

Close the command prompt.

If you have a larger network, you can use the ping program under MS

Windows to determine the MAC addresses of remote nodes:

1Make sure that the remote computer whose MAC address you wish to check is turned on and connected to the network.

138


146.

Open the Command Prompt.

The Command Prompt can be found in the Start menu, under

Programs/Accessories/Command Prompt.

147.

Ping the destination computer by using the following command:

ping IP Address (e.g., ping 192.168.2.15)

148.


If the destination computer is reachable, you will receive the ping replies and some information about network latency.

149.

Enter the following command: arp –g

150.


Your computer’s local ARP table will now be displayed. The

Physical Address column of this table shows the MAC address for each known IP address.

In order to connect to a remote computer on the same subnet, the local computer addresses Ethernet frames to the remote computer’s

MAC address. In order to do this, it must first determine the remote hardware address by issuing an ARP request. When you issue the ping request, your local computer automatically determines the remote computer’s MAC address and stores it in the local ARP table for future use.

If you wish to configure a PCMCIA Card for the Wireless LAN as an

Access Point, complete the following steps. Configuration as a

Station is described on page 142.

Configuring a Wireless LAN Access Point:




139


151.


152.

Use the Hardware drop-down menu to select the Wireless

LAN network card.

153.

Use the Type drop-down menu to select the Wireless LAN

Access Point interface type.

154.

Fill in the required settings for the Wireless LAN Access

Point.

Address: Assign an IP address for the access point. For this interface type, the address must be statically defined. Enter the address into this entry field.

Netmask: This interface type requires a statically defined netmask. Enter the network mask into this entry field.

Default Gateway: If you wish to use a default gateway with this interface, select Static from the drop-down menu and enter the gateway address in the entry field. Otherwise, select None.

SSID: Enter the network name for the wireless network here.

Enter a string without space characters here. This should be a string up to 32 characters long.

Channel: Use the drop-down menu to select a frequency channel for the network.

Use WEP: If you wish to use WEP encryption on the wireless

LAN, select Yes from the drop-down menu.

Security Note:

You should always use WEP encryption, as an unencrypted network presents a serious threat to network security.

If you select No from the drop-down menu, the WEP-specific configuration options will be ignored by the system.

140


WEP Authentication: If you wish to enable WEP authentication, select Yes from the drop-down menu. All nodes on the wireless network must be configured with the correct WEP Key.

Require WEP: If you do not wish to allow nodes not supporting

WEP onto the wireless network, choose Yes here.

WEP Key: Enter the WEP key to use in the WEP Key 0 through

3 entry fields. In order to use WEP encryption, you will need at least one WEP key - up to four can be used.

For a 40-bit key, enter a string with 5 hexadecimal digits separated by colons. In order to use a 104-bit key, enter a string of

13 hexadecimal digits separated by colons. The string must consist of hexadecimal digits. Please note that a hexadecimal number is two characters, each either a number (0-9) or a letter

(A-F).


Default WEP Key: Use the drop-down menu to choose one of the defined WEP Keys 0-3 which should be used as the default key. This key will be used as the current key, which all the other nodes must use to access the wireless network.

Access Mode: Choose the filter mode for the wireless LAN. If all nodes should be allowed access (subject, of course, to WEP restrictions), select All stations can get access.

If you wish to configure a positive filter select Stations in

Allowed MAC addrs can get access. To use a negative filter, choose Stations in Denied MAC addrs can not get access.

Allowed MAC addrs: If you have chosen to use a positive

filter, enter the MAC addresses of nodes allowed to access the wireless network in the access control list.

The access control list function is identical to the ordered list and is described in chapter on page 34.

141


Denied MAC addrs: If you have chosen to use a negative

filter, enter the MAC addresses of nodes explicitly not allowed to access the network in the access control list.

The access control list function is identical to the ordered list and is described in chapter on page 34.

155.



156.




157.




Configuring a Wireless LAN Station:




158.


159.

Use the Hardware drop-down menu to select the Wireless

LAN network card.

160.

Use the Type drop-down menu to select the Wireless LAN

Station interface type.

142


161.

Fill in the required settings for the Wireless LAN Station.

Address: Assign an IP address for the station. If you wish to use a static IP address for this interface, select Static from the dropdown menu and enter the address to use in the entry field. If you wish to have a gateway dynamically assigned via DHCP, select Assign by DHCP from the drop-down menu.





SSID: Enter the network name for the wireless network here. If you wish to establish a connection with an already existing

Wireless LAN, you must enter the existing network name.

Use WEP: If you wish to use WEP encryption on the wireless

LAN, select Yes from the drop-down menu.

Security Note:

You should always use WEP encryption, as an unencrypted network presents a serious threat to network security.

If you select No from the drop-down menu, the WEP-specific configuration options will be ignored by the system.

WEP Authentication: If you wish to enable WEP authentication, select Yes from the drop-down menu. All nodes on the wireless network must be configured with the correct WEP Key.

Require WEP: If you do not wish to allow nodes not supporting

WEP onto the wireless network, choose Yes here.

143


WEP Key: Enter the WEP key to use in the WEP Key 0 through

3 entry fields. In order to use WEP encryption, you will need at least one WEP key - up to four can be used.

For a 40-bit key, enter a string with 5 hexadecimal digits separated by colons. In order to use a 104-bit key, enter a string of 13 hexadecimal digits separated by colons. The string must consist of hexadecimal digits. Please note that a hexadecimal number is two characters, each either a number (0-9) or a letter

(A-F).


Default WEP Key: Use the drop-down menu to choose one of the defined WEP Keys 0-3 which should be used as the default key. This key will be used as the current key, which all the other nodes must use to access the wireless network.

162.


The system will now check the address and network mask for semantic validity. After a successful check, the new interface will appear in the Current Interface Status table. The interface is not yet enabled (status light is red)

163.




164.




144


4.3.2.4.

Virtual LAN

Virtual LAN (VLAN) technology allows a network to be segregated into multiple smaller network segments at the Ethernet level (layer 2).

This can be useful, for instance, when security considerations require that cerother ones. In large networks, this can also be useful to connect physically separate clients on the same logical network segment. tain clients only be allowed to communicate with certain

A VLAN-capable switch can assign ports to distinct groups. For example, a 20 port switch could assign ports 1 through 10 to VLAN 1, and ports 11 through 20 to VLAN 2. With such a configuration, a computer on port 1 would not be able to communicate with a computer on port 11. The technology essentially allows one physical switch to be divided into two logical ones.

In order to connect the security system to the virtual LANs, the system requires a network card with a tag-capable driver. A tag is a

4-byte header attached to packets as part of the Ethernet header. The tag contains the number of the VLAN that the packet should be sent to: the VLAN number is a 12-bit number, allowing up to 4095 virtual

LANs. The WebAdmin tool refers to this number as the VLAN Tag.

The tagged packets are only used to communicate between the VLANcompatible switch and the security system, the other computers on the network do not need to have tag-compatible network cards. The port on the switch connected to the security system must also be configured as an untagged port. Most VLAN-compatible switches can be configured by using a terminal program over a serial interface.

Example configuration:

145


The graphic at left shows an office where computers are distributed across two floors.

Each floor has a separate switch, and each computer is connected to the switch on its floor. In this configuration, PC1 and PC2 on the first floor and PC4 on the second floor will be connected together on VLAN 10. PC3, PC5 and PC6 will be connected together on VLAN 20.

The two switches must be configured as follows:

Switch a

Port VLAN

Tag tagged/ untagged

Switch b

Port VLAN

Tag

2 (PC1)

3 (PC2)

4 (PC3)

5

10

10

20

10,20

U

U

U

T

1

2 (PC4)

3 (PC5)

4 (PC6)

10

20

20 tagged/ untagged

U

U

U

In this configuration, it seems to PC3 as though it were connected through a single switch to PC5 and PC6.

In order to connect the computers to an external network (e.g., the

Internet), the interface on the security system (in the example, this is eth2) must be configured to support the VLANs.

146


Attention:

In order to configure a Virtual LAN interface, you will need a network card with a tag-capable driver. The hardware supported by the security system is listed in the Hardware Compatibility List for

Novell Security Manager powered by Astaro

available at


Configuring a Virtual LAN:




165.


166.


167.

Use the drop-down menu Type to select VLAN Ethernet

interface.

168.

Fill in the required settings for the VLAN Ethernet Interface type of interface:

Address: Assign an IP address for the virtual interface. If you wish to use a static IP address for this interface, select Static from the drop-down menu and enter the address to use in the entry field. If you wish to have a gateway dynamically assigned via DHCP, select Assign by DHCP from the drop-down menu.



147


148



VLAN Tag: Enter the VLAN tag to use for this interface.


Important Note:





QoS function is enabled. In this entry menu, enter the available bandwidth for the Uplink in full kilobits. This value can be determined either from the values of the upstream interface or from the router.

Downlink Bandwidth (kbits): This setting will only appear, if the QoS function is enabled. In this entry menu, enter the available bandwidth for the Downlink in full kilobits.

MTU Size: The MTU is the size (in bytes) of the largest transmittable packet. MTU stands for Maximum Transfer Unit. For connections, using the TCP/IP protocol, the data will be grouped into packets. A maximum size will be defined for these packets.

Packets larger than this value will be considered too long for the connection and fragmented into smaller ones before transmission. These data packets will be sent again. However, the per-

Using the Security System formance can be limited, if the upper value is too low.


The following values are the defaults for the VLAN Ethernet


169.



170.




171.




The new virtual interface will appear in the Hardware Device

Overview just as an additional IP address (IP alias) on a standard

Ethernet network card would. The Sys ID of this virtual interface is composed of the SysID of the network card and the number of the

VLAN tag.

149


4.3.2.5.

PPPoE-DSL Connection

This interface type is used to connect to the Internet over a DSL connection using the PPP over Ether-

net protocol. The configuration will require the DSL connection information, including username and password, provided by your

Internet Service Provider.

Note:

The installation and specific settings required for DSL connections is described in the DSL Network guide. Also note that, once the DSL connection is activated, the security system will be connected to your

ISP 24 hours a day. You should therefore ensure that your ISP bills on a flat-rate or bandwidth-based system rather than based on connection time. The DSL Network guide is available at


Configuring PPP over Ethernet (PPPoE-DSL):




172.


150


173.


Tip:


You cannot choose a network card that has already been configured with a primary network address.

174.

Use the Type drop-down menu to select the PPP over

Ethernet (PPPoE-DSL) connection interface type.

You will need the connection settings provided by your ISP to configure the following settings.

Address: If you have not been assigned a static IP address by your provider, keep the default Assigned by remote setting here. If you have a static IP address, choose Static from the drop-down menu and enter the address in the entry field.

Important Note:


Default Gateway: You should probably keep the default setting

Assigned by remote. Other possible values are Static and

None.

Username: Enter the user name, provided by your ISP.

Password: Enter the password, provided by your ISP.

Uplink Failover on Interface: This function will only be displayed if the Assigned by remote or Static is selected in the

Default Gateway drop-down menu.

You can setup a failover on an interface to the Internet with the help of a second Internet access and an additional network card.

Please, remember in doing so that the Internet security system supports only one DSL connection. A failover for the Internet access can, for example, consist of a permanent communication

151


152 line and a DSL access! If the primary connection fails, the Uplink will automatically be performed by the second Internet connection. In order to monitor the connection, the primary network

card sends four ping requests to the Uplink Failover check IP every five seconds. Only if all four ping requests are not replied to the Backup Interface is loaded.


Interface, the ping requests are still sent by the Primary Inter-

face. As soon as the security system receives the corresponding reply packages again, the Internet connection is again established by the Primary Interface.

Important Note:


Interface. Therefore you need next to the additional network card for the Backup Interface two separate Internet accesses.

Uplink Failover on Interface is by default disabled (Off). If you wish to use this virtual interface as primary connection, select Primary Interface from the drop-down menu. If this interface shall contain the standby connection, select the Back-

up Interface configuration.


Failover on Interface function. Enter the IP address of a host here, which replies to the ICMP Ping requests and which, in addition to that, is always reachable! The security system will send ping requests to this host: if no answer is received, the

backup interface will be enabled by the failover. In this entry field, there must always be an IP address for the failover!

QoS Status: In order to use Quality of Service (QoS) bandwidth management on an interface, enable this option. To enable

Using the Security System the Quality of Service (QoS) function, select On from the drop-down menu.

Important Note:





QoS function is enabled. In this entry menu, enter the available bandwidth for the Uplink in full kilobits. This value can be determined either from the values of the upstream interface or from the router. On an interface to the Internet, this value corresponds to the bandwidth of the Internet connection - on an

ADSL access the Uplink bandwidth amounts to 128 kBit/s and on a 2-Megabit fixed connection to 2048 kBit/s.

Downlink Bandwidth (kbits): This setting will only appear, if the QoS function is enabled. In this entry menu, enter the available bandwidth for the Downlink in full kilobits. On an interface to the Internet, this value corresponds to the bandwidth of the Internet connection - on an ADSL access the Uplink bandwidth amounts to 768 kBit/s and on a 2-Megabit fixed connection to 2048 kBit/s.

MTU Size: The MTU is the size (in bytes) of the largest transmittable packet. MTU stands for Maximum Transfer Unit. For connections, using the TCP/IP protocol, the data will be subdivided into packets. A maximum size will be defined for these packets. Packets larger than this value will be considered too long for the connection and fragmented into smaller ones before transmission. These data packets will be sent again. However, the performance can be limited, if the upper value is too low.

153


The following values are the defaults for the PPP over Ethernet

(PPPoE-DSL) connection: 1492 Byte.

175.



176.




177.




154


4.3.2.6.

PPTPoE/PPPoA-DSL Connections

This type of interface is required for DSL connections using the PPP over ATM protocol. To configure such a connection, you will need an unused Ethernet interface on the security system as well as an ADSL modem with an

Ethernet port. The connection to the Internet proceeds through two separate connections (see graphic): Between the security system and the ADSL modem, a connection using the PPTP over Ethernet protocol is established. The ADSL modem is, in turn, connected to the ISP using the PPP over

ATM dialing protocol.

The configuration will require the DSL connection information, including username and password, provided by your

Internet Service Provider.

Note:

The installation and specific settings required for DSL connections is described in the DSL Network guide. Also note that, once the DSL connection is activated, the security system will be connected to your

ISP 24 hours a day. You should therefore ensure that your ISP bills on a flat-rate or bandwidth-based system rather than based on connection time. The DSL Network guide is available at


155


Configuring PPTP over Ethernet (PPPoA-DSL):


2Click the New button to open the Add Interface window.

178.


179.


Tip:


You cannot choose a network card that has already been configured with a primary network address.

180.

Use the Type drop-down menu to select the PPTP over

Ethernet (PPPoA-DSL) connection interface type.

You will need the connection settings provided by your ISP to configure the following settings.

Address: If you have not been assigned a static IP address by your provider, keep the default Assigned by remote setting here.

If you have a static IP address, choose Static from the dropdown menu and enter the address in the entry field.

Important Note:


Default Gateway: You should probably keep the default setting

Assigned by remote. Other possible values are Static and

None.

Modem IP Address: Enter the IP address of your ADSL modem here. This address will usually be provided by your ISP or the

156

Using the Security System modem hardware, and cannot be changed.

Example: 10.0.0.138 (with AonSpeed)

NIC IP Address: Enter the IP address of the network card on the security system which is attached to the modem here. This address must be in the same subnet as the modem.


NIC Netmask: Enter the network mask to use here.


Address to Ping: In order to test the connection between the security system and the external network, you can enter an IP address of a host on the Internet (e.g., the DNS server of your

ISP) here. The security system will send ping requests to this host: if no answer is received, the connection will be broken.

Username: Enter the username, provided by your ISP.

Password: Enter the password, provided by your ISP.

Uplink Failover on Interface: This function will only be displayed if the Assigned by remote or Static is selected in the

Default Gateway drop-down menu.

You can setup a failover on an interface to the Internet with the help of a second Internet access and an additional network card.

Please, remember in doing so that the Internet security system supports only one DSL connection. A failover for the Internet access can, for example, consist of a permanent communication line and a DSL access! If the primary connection fails, the Uplink will automatically be performed by the second Internet connection. In order to monitor the connection, the primary network

card sends four ping requests to the Uplink Failover check IP every five seconds. Only if all four ping requests are not replied to the Backup Interface is loaded.


Interface, the ping requests are still sent by the Primary Inter-

face. As soon as the security system receives the corresponding

157


158 reply packages again, the Internet connection is again established by the Primary Interface.

Important Note:


Interface. Therefore you need next to the additional network card for the Backup Interface two separate Internet accesses.

Uplink Failover on Interface is by default disabled (Off). If you wish to use this virtual interface as primary connection, select Primary Interface from the drop-down menu. If this interface shall contain the standby connection, select the

Backup Interface configuration.


Failover on Interface function. Enter the IP address of a host here, which replies to the ICMP Ping requests and which, in addition to that, is always reachable! The security system will send ping requests to this host: if no answer is received, the backup interface will be enabled by the failover. In this entry field, there must always be an IP address for the failover!


Important Note:





Uplink Bandwidth (kbits): These settings will only appear, if the QoS function is enabled. In this entry menu, enter the available bandwidth for the Uplink in full kilobits. This value can be determined either from the values of the upstream interface or from the router. On an interface to the Internet, this value corresponds to the bandwidth of the Internet connection - on an

ADSL access the Uplink bandwidth amounts to 128 kBit/s and on a 2-Megabit fixed connection to 2048 kBit/s.

Downlink Bandwidth (kbits): These settings will only appear, if the QoS function is enabled. In this entry menu, enter the available bandwidth for the Downlink in full kilobits. On an interface to the Internet, this value corresponds to the bandwidth of the Internet connection - on an ADSL access the Uplink bandwidth amounts to 768 kBit/s and on a 2-Megabit fixed connection to 2048 kBit/s.

MTU Size: The MTU is the size (in bytes) of the largest transmittable packet. MTU stands for Maximum Transfer Unit. For connections, using the TCP/IP protocol, the data will be subdivided into packets. A maximum size will be defined for these packets. Packets larger than this value will be considered too long for the connection and fragmented into smaller ones before transmission. These data packets will be sent again. However, the performance can be limited, if the upper value is too low.

The following values are the defaults for the PPP over Ethernet

(PPPoA-DSL) connection: 1460 Byte.

181.



182.


159




183.




4.3.2.7.

PPP over Serial Modem Line

This type of interface is required if you wish to connect to the Internet through a

PPP modem via the serial interface. For the configuration you need a serial interface and an external PPP modem on the security system.

And you also need the DSLaccess data including password. You will get these data from your provider.

Setting up PPP over Serial Modem:

1In the Network tab open the Interfaces menu.

184.

Click on the New button to open the Add Interface menu.

185.

Now enter the name of the interface into the Name entry field.

186.

From the Hardware drop-down menu select the serial interface.

160


187.

From the Type drop-down menu select the PPP over serial

modem line type of interface.

Address: Keep the default setting Assigned by remote, if you have no fix IP-address.

If you have a fix IP-address select Static from the drop-down menu and enter the address into the entry field.

Important Note:

If you wish to configure the Uplink Failover on Interface failover for the network card, adhere to the description of this function for the entry of this network!

Default Gateway: Keep the default setting Assigned by

remote. Potential further settings are Static and None.

Username: Enter the user name, which you have received from your provider.

Password: Enter the password, which you have received from your provider.

Init String: Enter the string to initialize the modem into the entry field. Remember that it might become necessary to adjust the Init String to the modem. In this case, the Init String can be gathered from the associated modem manual. If you do not have the required documentation available, enter ATZ into the entry field.

Dial String: Enter ATDT plus the phone number into the entry field. Example: ATDT5551230

Reset String: Enter the Reset String for the modem into the entry field. Remember here as well that it might be necessary to adjust the Reset String to the modem. In this case you can gather it from the associated modem manual. If you do not have the required documentation available, enter ATZ into the entry field.

Flow Control: This function is used to control the data flow. If the data are transferred via the serial connection it might happen

161

Using the Security System that the system cannot process incoming data fast enough. To ensure that no data are lost, this method of controlling the data flow becomes necessary.

With the serial connection to methods are available:

- Hardware signals

- Software signals

Since, in a PPP-connection all 8 bits are used for the data transfer line and the transferred data contain the bytes of the command signs Control S and Control Q we recommend keeping the default setting Hardware and using a serial connection cable.

Line Speed: Set the speed in bits per seconds for the connection between the security system and the modem.

Common values are 57600 Bits/s and 115200 Bits/s

Uplink Failover on Interface: This function will only be displayed if in the Default Gateway drop-down menu the setting

Assigned by remote or Static has been selected.

With an interface to the Internet you can set-up a failover by means of a second Internet connection, e.g. via the serial interface and a PPP modem.

A failover for the Internet connection can for example consist of a permanent line and of an access via the serial interface! If the primary connection fails, the uplink will automatically be set up through the backup Internet access. In order to monitor the connection, the Primary Interface sends four ping requests to the

Uplink Failover check IP every five seconds. Only if all four ping requests are not replied to, the Backup Interface is loaded.

162


Interface the ping requests are still sent by the Primary Inter-

face. As soon as the security system receives the corresponding reply packages to the ping requests again, the Internet connection is again established by the Primary Interface.


Important Note:


Interface. Therefore you need two separate Internet accesses next to the additional network card.

Uplink Failover on Interface is by default disabled. If you wish to use this network card as primary Internet connection, then configure it in the Primary Interface drop-down menu. If this network card shall contain the standby connection, select the setting Backup Interface.


Failover on Interface function. Enter the IP address of a host here (e.g. the DNS server of your Internet Service Provider) , which replies to the ICMP Ping requests and which, in addition to that, is always reachable! The security system will send ping requests to this host: if no answer is received, the backup interface will be enabled by the failover. In this entry field, there must always be an IP address for the failover.

QoS Status: In order to use Quality of Service (QoS) bandwidth management on an interface, enable this option. To enable the Quality of Service (QoS) function, select On from the drop-down menu..

Important Note:





QoS function is enabled. In this entry menu, enter the available

163

Using the Security System bandwidth for the Uplink in full kilobits. This value can be determined either from the values of the upstream interface or from the router. On an interface to the Internet, this value corresponds to the bandwidth of the Internet connection.

Downlink Bandwidth (kbits): This setting will only appear, if the QoS function is enabled. In this entry menu, enter the available bandwidth for the Downlink in full kilobits. On an interface to the Internet, this value corresponds to the bandwidth of the Internet connection.

MTU Size: The MTU is the size (in bytes) of the largest transmittable packet. MTU stands for Maximum Transfer Unit.

For connections, using the TCP/IP protocol, the data will be grouped into packets. A maximum size will be defined for these packets. If now the maximum size is too high it might happen that data packets with information concerning the PPP over

Ethernet protocol are not delivered and recognized correctly.

These data packets will be sent again. However, the performance can be limited, if the upper value is too low.


The following value is the default for the Standard Ethernet


For the interface type PPP over Ethernet (PPPoA-DSL)

Connection a value for the maximum transmission rate must be defined in bytes in the MTU Size entry field.

For the PPP over Ethernet (PPPoA-DSL) Connection interface type a MTU-value is defined by default: 1460 Byte

188.



189.


164




190.




165


4.3.3.

Routing

Every network-connected computer uses a routing table to determine where outbound packets should be sent. The routing table contains the information necessary to determine, for instance, if the destination address is on the local network, or if traffic must be sent via a router – and, if a router is to be used, the table details which router is to be used for which network.

Static Routes

The security system will install static routing entries for directlyconnected networks by itself. Further routes, however, must be manually entered. This is the case, for instance, when the local network includes a router to be used for access to a specific network.

These routes, called static routes, contain information about how to contact a non-directly connected network.

This menu allows you to define which network card or router should be used to contact various external networks.

Defining Static Routes:

1Under the Network tab, open the Routing menu.


The Add Static Route window will open.

191.

In the Network drop-down menu, choose the network you wish to define a route for.

The Network drop-down menu contains all static networks, as well as those you have defined in the Networks and

Interfaces menus.

166


192.

In the Target drop-down menu, select the destination to which packets should be forwarded.

Names in brackets are interfaces, while names without are hosts or routers. Names without brackets are either hosts or routers.

193.


When a new route has been defined and saved, it will appear in the

Static Routes table. To remove an entry, click delete.

Kernel Routing Table opens the Kernel Routing Table window.

The Kernel Routing Table will be displayed in a separate window. This window shows all on the system currently active routes. The system will check each rule in the order of the list, using the first applicable route. By default, the default routes associated with network cards are already entered, and are not editable.

Clicking on the Show button

167


4.3.4.

NAT/Masquerading

4.3.4.1.

NAT

The Network Address

Translation (NAT) function translates one set of IP addresses (usually private ones) to addresses in another set (usually public).

NAT makes it possible for computers on an internal

LAN to use private IP addresses, while still allowing them to communicate – through the security system – with the public

Internet.

When a client sends an IP packet to the router, NAT translates the sending address to a different, public IP address (from the address space given by the Internet provider) before forwarding the packet to the Internet. When a response packet is received, NAT translates the public address into the original address and forwards it on to the internal client. Depending on system resources, the NAT function can handle arbitrarily large internal networks.

Destination Network Address Translation (DNAT) is a special case of NAT whereby the destination addresses of packets are translated. This is especially useful when an internal network uses private

IP addresses, but an administrator wishes to make some services available to the public Internet.

Important Note:

PPTP VPN Access is incompatible with DNAT.

Example:

168


Your internal network uses the address space 192.168.0.0/

255.255.255.0 and a web server running at IP address 192.168.0.20

port 80 should be available to Internet-based clients.

Because the 192.168 address space is private, the Internet-based clients cannot send packets directly to the web server. It is, however, possible for them to communicate with the external (public) address of the security system. DNAT can, in this case, take packets addressed to port 80 of the system’s address and forward them to the internal web server.

Note:

The method of setting up a web server behind the Internet security system is described in the Web Server/DNAT guide. The Web

Server/DNAT guide is available at http://www.novell.com/

documentation/nsma51.

Source Network Address Translation (SNAT) is another special case of NAT, and functions just as DNAT does, with the difference that source addresses (rather than destination addresses) are translated.

This is useful in complex networks where replies should be sent from other network addresses.

Tip:

To build a simple translation system from an internal network to the

Internet, use the Masquerading function instead of SNAT.

In contrast to Masquerading, which is dynamic, SNAT uses a static address translation. That is, every internal address is translated to its own externally visible IP address.

169


Note:

In order to forward port 443 (HTTPS) to an internal server, you must first change the value of the WebAdmin TCP Port (e.g., 1443) for

WebAdmin in the System/WebAdmin Settings menu. This function is described in chapter in chapter General Settings.

Note:

Because translation occurs before Packet filtering, you must ensure that appropriate rules are entered in the Packet Filter/Rules menu.

More information on setting packet filter rules can be found in chapter on page 190.

Defining NAT rules:

1In the Network tab, open the NAT/Masquerading menu.

2In the Name field, enter a descriptive name for this NAT rule.

194.

In the Rule type drop-down menu, select the DNAT/SNAT function.


195.

In the Packets to match window, define which packets should be translated.

At least one parameter in this window must be defined in order to create a valid DNAT/SNAT rule. The setting No match means that packets will not be matched on the basis of this parameter.

Source address: Choose the original source address here: This can be either a single host or an entire network.

Destination address: Choose the original destination address here: This can be either a single host or an entire network.

170


Service: Choose the original service here: the service is defined by source and destination ports as well as protocol used (e.g.,

TCP).

Note:

A service can only be redirected when the communicating addresses are also redirected. In addition, a service can only be redirected to another service when the two services use the same protocol.

196.

Use the next drop-down menus to define how the packets should be translated.

At least one parameter in this window must be defined in order to create a valid DNAT/SNAT rule. If you redirect the original address to an entire network, the addresses in that network will be used one after another.

Change Source to (SNAT): Choose a new source address for the translated packets. This can be either a single host or an entire network.

Service source: This drop-down menu will only be shown when you have chosen an address in the Change source to menu.

Only services with one source port can be used here.

Change Destination to (DNAT): Choose a new destination address here. This can be either a single host or an entire network.

Service destination: This drop-down menu will only be shown when you have chosen an address in the Change destination

to menu.

197.

Save the settings by clicking Add.

After successfully defining a rule, it will appear in the NAT Rules table list. The further functions in the NAT table can now be used for further customization.


171


Edit rule: Click edit to load the rule into the Edit NAT Rule window.

The rule can now be changed as desired.

Delete rule: Click Delete to remove a rule from the list.

4.3.4.2.

Masquerading

Masquerading is a special case of SNAT, which allows you to associate many internal (private) addresses with one external (public) address. This allows you to hide internal IP addresses and network information from the outside network.

The differences between Masquerading and SNAT are:

• Masquerading requires a source network. It will automatically include all services (ports) on that network.

• The translation only occurs when the packet is sent via the supplied network card. The new source address will be that of the interface.

Masquerading is intended to hide privately addressed LANs behind one official (public) Internet address.

172


Defining Masquerading rules:

To define masquerading rules, select which network should masquerade as which network card. Normally, the external network card is used.

Note:

In order for clients from the defined network to build a connection to the Internet, the appropriate rules must be entered in the Packet

Filter/Rules menu.

More information on setting packet filter rules can be found in chapter on page 199.


2In the Name field, enter a descriptive name for this Masquerading

Rule.

198.

Use the Rule Type drop-down menu to select

Masquerading.


199.

Use the Network drop-down menu to select a network.

200.

Use the Interface drop-down menu to select an interface.

201.


After a masquerading rule has been defined and added, it will appear in the NAT Rules table. The further functions in the NAT table can now be used for further customization.


Edit Masquerading rules: Click edit to load the rule into the Edit

NAT Rule window. The rule can now be changed as desired.

Deleting Masquerading rules: Click delete to remove a rule from the list.

4.3.4.3.

Load Balancing

173


The Load Balancing function allows you to balance incoming connections (e.g.

SMTP or HTTP sessions) across different servers behind the security system. tical HTTP servers with IP addresses 192.168.66.10 and

192.168.66.20. Load Balancing can split incoming HTTP requests between the two servers evenly.

Example: In the enterprise’s DMZ sit two iden-

Before the load-balancing rule can be defined, the two HTTP servers must be defined as networks (consisting of single hosts) in the

Definitions/Networks menu. Next, add both to a single network group.

The procedures for adding networks and network groups are described in chapters and 106, respectively.

Once these definitions have been saved, the load balancing rules can be defined.

Defining Load Balancing rules:


2Enter a descriptive name for the load-balancing rule in the Name entry field.


202.

Enter a descriptive name for the load-balancing rule in the

Name entry field.

203.

Use the Rule Type drop-down menu to select Load

Balancing.

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204.

In the Pre-Balancing Target window, select the original destination address and service.

Address or Hostname: Select the original destination address here. This should usually be the external address of the security system.

Service: Select the destination port (service) to be balanced.

205.

In the Post-Balancing Target Group drop-down menu, select the new address. This will usually be a network group composed of single hosts.

When the load-balancing rule has been defined and saved, it will appear in the NAT Rules table. The further functions in the NAT table can now be used for further customization.

Editing Load Balancing rules: Click edit to load the rule into the

Edit NAT Rule window. The rule can now be changed as desired.

Deleting Load Balancing rules: Click delete to remove a rule from the list.

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4.3.5.

DHCP Server

The Dynamic Host Con- figuration Protocol (DHCP) automatically distributes addresses from a defined IP address pool to client computers. It is designed to simplify network configuration on large networks, and to prevent address conflicts. DHCP distributes IP addresses, default gateway information, and DNS configuration information to its clients.

In addition to simplifying the configuration of client computers and allowing mobile computers to move painlessly between networks,

DHCP helps to localize and troubleshoot IP address-related problems, as these are mostly issues with the configuration of the DHCP server itself. It also allows for a more effective use of address space, especially when not all computers will be active at the same time. as addresses can be distributed as needed and re-used when unneeded.

Configuring the DHCP Server:

1In the Network tab, open the DHCP Server menu.

2In the Interface drop-down menu, select the interface from which the IP addresses should be assigned to the clients.

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Click Enable next to Status to enable the function.

Another entry window will open.

207.

Use the Range Start and Range End menus to set the address space from which IP addresses will be distributed.

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By default, the configured address area of the network card will appear in the entry field.

The settings will take effect without further confirmation.

Assigning DNS servers, Gateway IP and WINS server:

You can transmit further parameters for the network configuration to the clients. Such as the DNS Server Addresses and the Default

Gateway to be used by the clients. The security system itself will usually fill both of these functions: in this case, you should enter the internal address of the system in these entry fields.

The DNS Proxy is configured in the Proxies/DNS menu. Please see chapter on page 241 for a description of how to use the DNS proxy.

NetBIOS networks can also use a WINS server for name resolution.

WINS stands for Windows Internet Name Service. WINS servers are

MS Windows NT servers with both the Microsoft TCP/IP stack and the

WINS server software installed. These servers act as a database matching computer names with IP addresses, thus allowing computers using NetBIOS networking to take advantage of the TCP/IP network.


2In the entry fields DNS Server 1 IP and DNS Server 2 IP, enter the IP address of your name servers.

208.

In the Gateway IP entry field, enter the IP address of the default gateway.

209.

If you wish to assign a WINS server, configure the following two settings:

WINS Server IP: Enter the IP address of the WINS server here.

WINS Node Type: Use the drop-down menu to choose which kind of name resolution clients should use. If you choose Do not

set node type, the client will choose by itself which to use.

210.


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Configuring Static Mappings:

This function allows you to ensure that specific computers are always assigned the same IP address. To configure this function, you will need to know the MAC (hardware) address of the client’s network card.

Determining the MAC addresses of network cards is described on page 138.


2In the Static Mappings window, make the following settings:

MAC Address: In the MAC Address entry field, enter the MAC address of the network card. The MAC address must be entered as in the following example

Example: 00:04:76:16:EA:62

IP Address: Enter the IP address into this entry field. The address must be within the range specified by the Range Start and Range End options.

211.


The static address mapping will appear in the Static Mapping Table.

To remove an entry from this table, click delete.

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Current IP Leasing Table

The Current IP Leasing table shows all current IP address mappings. If more than one entry is shown for the same IP address, only the last-listed one is valid. This table will only be shown when there are entries in it.

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4.3.6.

PPTP VPN

Point-to-Point Tunneling Protocol (PPTP) allows single Internetbased hosts to access internal network services through an encrypted tunnel. PPTP is easy to set-up, and requires on Microsoft Windows systems no special client software.

PPTP is included with versions of Microsoft Windows starting with

Windows 95. In order to use PPTP with this security system, the client computer must support the MSCHAPv2 authentication protocol.

Windows 95 and 98 users must apply an update to their systems in order to support this protocol. The update is available from Microsoft at: http://support.microsoft.com/support/kb/articles/Q191/5/40.ASP

Select the VPN Update and, if you use Windows 95, also the RAS

Update.

PPTP VPN Access

This window allows you to enable or disable PPTP VPN access by clicking the En-

able/Disable button.

Logging: This drop-down menu allows you to choose how detailed the information recorded in the PPTP Logs should be. The Extensive setting should be used when you are using the Live Log to debug connection problems. When you start the connection, you can view the process in real time.

The PPTP Live Log is in the Local Logs/Browse menu.

Encryption: This drop-down menu allows you to choose between encryption strengths (40-bit or 128-bit). Note that, in contrast to

Windows 98 and Windows ME, Windows 2000 does not come with 128 bit encryption installed: to use this kind of connection, the High

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Encryption Pack or Service Pack 2 must be installed. SP2 cannot be uninstalled later.

Security Note:

You should always set Encryption to Strong (128-bit) except when your network includes endpoints, which cannot support this.

Authentication: Use this drop-down menu to select an authentication method If you have defined a RADIUS server in the Sys-

tem/User Authentication menu, you can use RADIUS authentication here as well.

The configuration of the Microsoft IAS RADIUS server and the configuration of RADIUS within WebAdmin is described in chapter on page 66.

The PPTP Live Log provides a list of important events, including error messages, related to the PPTP service. The Logging menu can be used to select which events are logged.

PPTP IP Pool

This menu is used to define which IP addresses PPTP hosts should be assigned.

The default settings assign addresses from the private IP space 10.x.x.x. This network is called the PPTP Pool, and can be used in all of the other security system configuration options. If you wish to use a different network, simply change the definition of the PPTP Pool, or assign another defined network as PPTP Pool here.

PPTP users are defined in the Definitions/Users menu. It is also possible to assign specific users to specific IP addresses. These addresses do not need to be part of the defined PPTP pool. To use these addresses in other parts of the system configuration, such as

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Using the Security System the packet filter, they must be defined as single hosts (i.e., networks with netmask 255.255.255.255) or as a part of a larger network.

Note:

If you use private IP addresses for the PPTP pool and you wish

PPTP-connected computers to be allowed to access the Internet, appropriate Masquerading or NAT rules must be in place.

PPTP Client Parameters

This window allows you to define name servers (DNS and WINS) and the name service domain, which should be assigned to hosts during the connection establishment.

Connections with MS Windows 2000:

The following example shows how to configure a PPTP VPN connection on a Windows 2000 host.

1Under the Network tab, open the PPTP VPN Access menu.

2In the PPTP VPN Access window, enable the system by clicking

Enable.

The status light will show green and the menu will open.

212.

In the PPTP VPN Access window, make the settings for the network access:

Logging: Keep the setting Normal.

Encryption: In the drop-down menu, select the encryption type.

The available options are weak (40 bit) and strong (128 bit).

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Note that, in contrast to Windows 98 and Windows ME, Windows

2000 does not come with 128 bit encryption installed: to use this kind of connection, the High Encryption Pack or

Service Pack 2 must be installed. SP2 cannot be uninstalled later. The selected encryption strength will take effect immediately.

Important Note:

Both sides of the connection must use the same encryption strength. If WebAdmin is set to use 40-bit encryption, and the

MS Windows 2000 client is set to use 128-bit encryption,

Windows will incorrectly report that the connection has been established.

Authentication: Use the drop-down menu to select a service.

213.

Now define which IP addresses should be assigned to the hosts when connecting. In the PPTP IP Pool window, use the

Network drop-down menu to select a network. The chosen network will be used immediately.

The PPTP Pool network is selected by default.

The IP address, network mask, and number of free addresses will appear below the drop-down box.

Users will be assigned an address from this range automatically.

214.

In the PPTP Client Parameters window, DNS and WINS servers for PPTP clients can be defined. Two servers may be defined for each.

Client DNS servers: Enter the IP addresses of the DNS servers to use.

Client WINS Servers: Enter the IP addresses of the Windows name servers to use.

Client domain: Enter the DNS domain that the client should append to DNS requests.

215.


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The rest of the configuration takes place on the user’s machine. This will require the IP address of the server, as well as a valid username and password. These should be supplied by the security system administrator.

1In Microsoft Windows 2000, open the Start/Settings/Network

and Dialup Connections menu.

2Click the Make New Connection icon.

The Network Connection Wizard will open.

Then click on the Next button.

216.

Select the following option: Connect to a private network

through the Internet.


217.

If you have a permanent connection to the Internet, select the following option Do not dial the initial connection.


Otherwise, select the Dial other connections first option and select your provider from the selection menu. These settings can be changed later in the Properties dialog box.

218.

In the Destination address entry field, enter the IP address of the server.


219.

In the Connection Availability window, select whether the connection should be available to all local users, or just this account.


220.

In the next text entry field, enter a descriptive name for this

PPTP connection.


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221.

In the Start/Settings/Network and Dialup Connections, a right-click on the new icon will allow you to open the

Properties window and configure further options:

General: This allows you to change the hostname or destination address of the connection. In the Connect First window, select any network connections that need to be established before setting up the PPTP session.

Options: The dial and redial options can be defined here.

Security: Choose the Advanced (Custom Settings) option.

Next click the Settings button. Leave these settings as they are.

Network: In the Type of VPN Server I am calling menu, select the Point-to-Point-Tunneling Protocol (PPTP) option.

Sharing: This menu allows you to share the PPTP connection with other computers on the local network.

To start the PPTP connection, simply click the new icon in the

Start/Settings/Network and Dialup Connections menu. Further information is usually available from the network administrator.

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4.3.7.

Accounting

When the Accounting function is enabled, the security system will track all transmitted data and compile statistics about it. The accounting menu allows you to select which network cards should be monitored. You can download the data from the Log

Files/Accounting menu, or view daily reports in the Reporting/

Accounting menu.

Important Note:

In the normal case, you should only enable Accounting on one network card, because, if more than one card is monitored, data forwarded from one monitored interface to another monitored one will be counted twice.

If you use Masquerading, you should probably use Accounting on the internal interface. Otherwise, data packets dropped by the security system filters will be included, and will appear to come from the wrong interface.

It is also possible to exclude certain Hosts or Networks from the

accounting records. After installation, all networks are included in accounting records.

It may be useful to block certain hosts or networks from accounting data, for instance when a DMZ host only communicates with internal systems, but you are only interested in collecting accounting data for outbound traffic. ince it might only be used for internal means, it might not be useful to consider its traffic data.

In the Reporting/Accounting menu, you can monitor the collected

accounting data and edit accounting rules.

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Important Note:

Do not use accounting on network interfaces. Doing so may overload the system.

Configuring Traffic Accounting:

1In the Network tab, open the Accounting menu.

2Enable the function by clicking the Enable button.

The status light will show green and another entry window will open.

222.

In the Interfaces selection field, choose the network cards.

Please see chapter on page 31 for a description of how to use

selection fields.

223.

Use the Ignored Networks selection menu to choose which networks to ignore.

The settings in the Traffic Accounting menu will immediately be enabled.

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4.3.8.

Ping Check

Ping allows you to test the connection with a remote host on the IP level. Please note that these tools require that the ICMP on firewall option under the Packet

Filter/ICMP menu be enabled. Ping sends an ICMP Echo Packet to the remote machine. When this packet is received by the remote machine, its TCP/IP stack will generate an ICMP Reply Packet and send it back. This allows you to test that IP-level connectivity with the remote machine.

Ping Check also allows you to check the connection with a host by entering the DNS hostname. In order to do that, DNS Proxy must be enabled in the Proxies/ DNS menu.

Note:

• Ping will not work unless ICMP on firewall (in the Packet

Filter/ICMP menu) is activated.

• Name Resolution will not work unless DNS Proxy (in the

Proxies/DNS menu) is activated.

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Using Ping:

1Under the Network tab, open the Ping Check menu.

2Use the Ping Host drop-down menu to select a network card.

If this is an interface with a host, configured in one of the menus

Interfaces or Networks, you can select it directly from the drop-down menu.

(Example: Internal (Address) for the internal network card on the security system).

For another host in the network, select the setting Custom

Hostname/IP Address from the drop-down menu.

224.

In the Hostname /IP Address entry field, enter the IP address or hostname.

225.

Click Start to begin the test connection.

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4.4. Intrusion Protection

The Intrusion Protection System (IPS) recognizes attacks with the help of a signature-based Intrusion Detection set of rules. The system analyzes the complete traffic and automatically blocks attacks before they can reach the network.

The existing set of rules and/or IPS attack signatures are updated through the Pattern Up2Date function. New IPS attack signatures will automatically be imported as IPS rule to the IPS set of rules.

4.4.1.

Settings

Global Settings

In the window, configure the basic settings for the

Intrusion Protection Sys-

tem (IPS) option.

Status: Clicking on the Enable button enables the option.

Local Networks: From the selection field select those networks that should be monitored by the Intrusion Protection System (IPS). If no specific network is selected, the complete data traffic will be monitored.

Portscan Detection

The Portscan Detection

(PSD) feature allows you to detect possible attacks from unauthorized users. Portscans are used by hackers to probe secured systems for available services: In order to intrude into a system, or to start a Denial-of-Service (DoS) attack, attackers need information on network services. If this information is available, attackers might make use of the security

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Using the Security System deficiencies of these services. Network services using the TCP and

UDP Internet protocols, can be accessed via special ports and this port assignment is generally known, for example the SMTP service is generally assigned to the TCP Port 25. The ports, used by the services are referred to as open, since it is possible to establish a connection to them. Whereas unused ports are referred to as closed, every attempt to connect with them fails. The attacker tries to find the open ports with the help of a particular software tool, i.e. the Port Scanner.

This program tries to connect with several ports on the destination computer. If it is successful, the tool displays the relevant ports as open and the attacker has the necessary information, showing him which network services are available on the destination computer.

The following is an example of the information returned by a port scanner:

Interesting ports on (10.250.0.114):

(The 1538 ports scanned but not shown below are in state: closed)

Port State Service

25/tcp open smtp

135/tcp open loc-serve

139/tcp filtered

445/tcp open netbios-ssn

Microsoft-ds

1032/tcp open iad3

Since 65535 ports are available for the TCP and UDP Internet protocols, the ports are scanned at very short intervals. When the firewall detects an unusually large number of attempts to connect to services, especially when these attempts come from the same source address, this is almost certainly due to a portscan.

PSD watches for such scans and immediately informs the administrator via e-mail when one is detected. The administrator can also decide what further measures should be taken in response to the scan. The e-mail address of the administrator can be configured in the

System/Settings menu.

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Security Note:

The administrator should take special care that all systems have the most recent security patches installed.

The Up2Date service, which updates the security system itself, is detailed in chapter on page 48.

Notification Levels

If the Intrusion Protec- tion System (IPS) detects IPS attack signatures or prevents an intrusion, the system will send a message to the administrator. The email address of the administrator can be configured in the

System/Settings menu.

Detected Packets: Use this drop-down menu to select the severity level from which on a warning should be sent (Intrusion Detection).

• All levels: for each level of risk.

• High and medium severity: for high and medium levels of risk.

• High severity only: only for high risk levels.

• None: no warning will be sent.

Blocked Packets: Use this drop-down menu to select the level of risk, from which on a warning should be sent (Intrusion Prevention).

• All levels: for each level of risk.

• High and medium severity: for high and medium levels of risk.

• High severity only: only for high risk levels.

• None: no warning will be sent.

4.4.2.

Rules

The Rules menu contains the Intrusion Protection System (IPS) set of rules. The already existing base set of rules with the IPS attack signatures can be updated through the Pattern Up2Date function, if

192

Using the Security System desired. New IPS attack signatures will automatically be imported as

IPS rule to the IPS rules table.

The Pattern Up2Date function is described in further detail in chapter on page 48.

IPS Rules Overview

The overview contains all IPS sets of rules.

The functions in the overview from the left to the right:

/ : Clicking on the status light enables the IPS set of rules.

/ : The IPS rule can be configured as alarm rule (Intrusion

Detection) or as blocking rule (Intrusion Prevention). Clicking on the icon switches the application of the IPS rules in this group.

: Clicking on the folder icon opens the sub-tab with all protocols of this group.

By clicking again on the icon, you will get back to the overview. The additional functions in the sub-tab are described in the „IPS Rules

Sub-tab“ section.

Group: The name of the IPS group of rules is displayed in this column. The groups are put in alphabetical order according to this name. Clicking in the header automatically displays the groups in deor increasing alphabetical order.

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Hits: This column displays, how often a rule from the group became active.

Info: This column provides short information on this IPS rule group.

The IPS Rule Sub-tab

All IPS rules of a group are listed in this sub-tab. The sub-group can be opened in the overview by clicking on the folder icon ( ).

The functions in the sub-tab from the left to the right:

/ : Clicking on the status light enables the IPS rule.

/ : The IPS rule can be configured as alarm rule (Intrusion

Detection) or as blocking rule (Intrusion Prevention). Clicking on the icon switches the application of the IPS rule in this group.

: Return to the overview by clicking on the folder icon.

Group: The name of the IPS group of rules is displayed in this column.

Hits: This column displays, how often a rule from the group became active.

Info: The first line provides short information on this IPS rule group.

You can obtain detailed information on the IPS rules by clicking on the correspondent icon with the mouse.

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: This window presents the parameters of this as Low Layer

Information.

: Clicking on the icon connects you to the correspondent link in the Internet. The Website contains further information on the IPS rule. This information is compiled in projects such as Common

Vulnerabilities and Exposures (CVE) and published in the Internet.

Setting an IPS rule:

You can add your own IPS rules to the set of rules. The rules are based on the syntax of the Snort Open Source ID System. Manually configured IPS rules are always locally imported to an IPS set of rules. For more information please see the following Internet address: http://www.snort.org.

1Under the Intrusion Protection tab, open the Rules menu.

2Click on the button.


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226.


Description: Enter a description of the rule in the entry field.

Example:

Large ICMP packet

Selector: Enter the selection parameters for the IPS rule in the

Snort syntax in the entry field.

Example: icmp $EXTERNAL_NET any -> $HOME_NET any

Filter: Enter the real identification parameter for the IPS rule in

Snort syntax in the entry field. Please make sure that the entry ends with a ;-sign.

Example: dsize: >800;

227.

Save your configuration by clicking Add local Rule.

The new IPS rule is always locally imported to an IPS set of rules.

The rule is immediately enabled (status light shows green).

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4.4.3.

Advanced


This menu allows you, to configure additional settings for the Intrusion Protec-

tion System (IPS). This should, however, only be done by experienced users.

Policy and Exclusions

Policy: From this drop-down menu select the security policy that the

Intrusion Protection System should use, if a blocking rule detects an

IPS attack signature.

• Drop silently: the data packet will only be blocked.

• Terminate connection: a TCP Reset and/or ICMP Unreachable

(for UDP) packet will be sent to both communication partners and the connection will be terminated.

IPS Network Exclusions: Specific connections between the networks of the Intrusion Protection System (IPS) can be excluded in this selection menu.

The connections will be listed in a table below the selection menu.

Clicking the trash can icon ( ) deletes the defined connection from the table.

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Performance Tuning

The performance of the Intrusion Prevention System (IPS) can be enhanced through the settings in this window, in which the servers and ports are defined. The correspondent IPS rules will only be used for the configured servers and ports.

The server must first be added as host in the Definitions/Networks menu. For more information on adding hosts, please refer to chapter on page 106.

Note:

If you don’t configure a server in this window, the Intrusion

Protection System (IPS) will monitor the complete data traffic according to the settings in the Global Settings window.

HTTP Service: In this drop-down menu select the target port for the

HTTP data traffic, by selecting a Service. In the Definitions/Ser-

vices menu, you can change or add a Service, if necessary. The added service will only use the target port number. In the case of a port range, only the first and last port will be used.

Example: In a port range 80:8080 the HTTP rule will be used for the target port 80 and 8080.

HTTP Servers: Select the HTTP servers in this selection field.

DNS Servers: Select the DNS servers in this selection field.

SMTP Servers: Select the SMTP servers in this selection field.

SQL Servers: Select the SQL servers in this selection field.

Telnet Servers: Select the Telnet servers in this selection field.

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4.5. Packet Filter

The Packet Filter is the central part of the firewall. In the Rules menu you define the allowed data traffic between the networks and hosts in the form of Packet filter rules. You can also define specific packets, which will never be allowed to pass through the firewall. The packet filter management is done in the Rules table.

The tools in the ICMP menu allow you to check the network connections and functions of the security system. The additional and reporting functions are available in the Advanced menu.

4.5.1.

Rules

The Rules menu allows you to define packet filter sets of rules. These rules are defined with the help of the

network and service definitions.

In general, there are two basic kinds of packet filtering policy:

• Default allow – the rules explicitly define which packets are blocked; all others are allowed.

• Default deny– the rules explicitly define which packets are allowed; all others are dropped.

This security system uses a Block all packets policy, as this policy is inherently much more secure. This policy requires you to define explicitly, which IP packets will be allowed to pass the filter. All other packets will be blocked and – depending on the action chosen – displayed in the Packet Filter Live Log. The Packet Filter Live Log can be opened in this menu by clicking on the Live Log button or under the Packet Filter/Advanced menu. The functions in the

Packet Filter Live Log are described in chapter on page 214.

Example:

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Network A is a subset of network B. Rule 1 allows SMTP traffic destined for Network A. Rule 2 blocks SMTP for network B. Result:

Only SMTP traffic for network A will be allowed. SMTP packets from the rest of network B IP addresses will be blocked.

A packet filter rule is defined by the source address (Source), a

service (Service), the destination address (Destination) and a

Response (Action).

The following values can be chosen as source and target addresses.

Please see the corresponding chapters of this for a more detailed explanation of how to configure and manage these targets.

• A Network – networks are defined in the Definitions/Networks menu.

• A Network Group – network groups are defined in the Defin-

itions/Network menu.

• An Interface network – logical networks are defined automatically by the system when configuring a new network card or interface. Interfaces can be configured in the

Network/Interfaces menu.

• An IPSec Remote Key Object (IPSec User Group) – the IPSec

User groups are defined in the Definitions/Networks menu.

This address or port range is required when configuring packet filter rules for IPSec Road Warrior Endpoints.

A new defined packet filter rule is initially disabled, when it is added to the table. Active rules are applied in the given order, ending with the first matching rule. The order of this process will be displayed in the table through the Position number (second column from the left). If you re-sort the rules table later, for example according to the

source address please, note that the rules won't be displayed in the order in which the system processes the rules. If, however, you change the numerical rule order via the Position number, the processing order will change correspondingly. In our example, if rule

2 were moved to be before rule 1, all SMTP traffic for both networks

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Using the Security System would be blocked. Be very careful when defining rules and their order, as this will determine the security of your firewall.

Important Note:

When one filter rule applies, all other rules will be ignored! The sequence of rules is thus very important. Never place a rule like Any

(Source) – Any (Service) – Any (Destination) – Allow (Action) at the top of the rule set.

Setting Packet Filter Rules:

1Under the Packet Filter tab, open the Rules menu.



228.


Position: Define the line of the table, in which the packet filter rule will be entered. It is possible, to change the sequence of the packet filter rules later. By default, the rule is placed at the end

(To Bottom) of the rules table.

Group: For a smooth management of the set of rules, the packet filter rules can be grouped together in one group. This does not influence the way, in which a rule will be processed within the set of rules.

For the first rule, no group can be selected from the drop-down menu yet. New groups are defined in the set of rules table.

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202

Source: In the drop-down menu, select the source address of the data packets. The Any setting applies to all IP addresses, regardless of whether these are publicly assigned IP addresses or private IP addresses according to RFC1918.

Service: Use the drop-down menu to select a service.

This list includes all the pre-defined services included in the

Security system, as well as the ones that you defined yourself.

This allows you to define precisely which traffic should be allowed. The Any setting represents here all combinations of protocols and source and/or destination ports.

Destination: In the drop-down menu, select the destination address of the data packets.

The Any setting applies to all IP addresses, regardless of whether these are publicly assigned IP addresses or private IP addresses according to RFC1918.

Action: In the Action drop-down menu, select the action to execute if a data packet complies with the settings for Source,

Service and Destination: In connection with this action, the priority for the Quality of Service (Qos) function is also configured here.

Important Note:

In order to enable the priorities high priority and low priority, you must select the respective interface for the QoS function in the Network/Interfaces menu and also define the values Up-

link Bandwidth (kbits) and Downlink Bandwidth (kbits).

Allow: All packets, complying with this rule are allowed to pass.

Allow (high priority): All packets, complying with this rule are allowed to pass. In addition, this data traffic gets a higher priority if the Uplink is overloaded.


Allow (low priority): All packets, complying with this rule are allowed to pass through. In addition, this data traffic gets a lower priority if the Uplink is overloaded.

Drop: All packets matching this rule are blocked.

Reject: All packets, complying with this rule are denied. In addition, the firewall will send an ICMP error to the sending computer.

Log: Any violation of the rule will be reported in the Packet

Filter Live Log. This action is enabled by clicking on the check box.

For such filter violations, which take place very often, and which are not particularly security-relevant and only reduce the readability of the Packet Filter Live Log (e.g., Windows

NetBIOS broadcasts), we recommend not to enable the Log function.

Comment: In this entry field you can optionally enter a comment on a rule.

229.

Save your configuration by clicking Add Definition.

If the definition was successful, the new Packet filter rule will be added to the rule table in a deactivated state, marked by the red status light.

230.

Activate the Packet filter rule by clicking the status light.

After the rule is added to the table, further options are available for managing and editing rules in the rules table.

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Note:

By default, new rules are added in an inactive state in the table. The rule will only become effective when it is set to be active. See

Activating/deactivating rules.

The Rules Table

Each packet filter rule will be displayed in the table through a separate line: The different settings will either be displayed as alphanumeric signs or as symbols. While all settings with alphanumeric signs can be edited by clicking on the correspondent field, this is not possible with all symbol displays.

The following table explains all symbols from the rules table:

The Symbols

Icon Column Display/Setting

Trash can

Status light

Status light

Packet filter rule is disabled

Packet filter rule is enabled

Source/Destination Host

Source/Destination Network

Source/Destination Network group

Source/Destination DNS Hostname

Source/Destination IPSec User Group

Action Allow

Action Allow (high priority)

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Icon Column

Action

Action

Action

Log

Log

Display/Setting

Allow (low priority)

Drop

Reject

Log disabled

Log enabled

Adding/editing groups: Clicking in the field in the Group column opens an entry window. Clicking on the Save button saves your changes.

In order to interrupt this process, click on the Cancel button.

Enabling/Disabling Packet filter rules: The status light in the fourth column shows the rule status. Clicking the status light toggles the state between active (green light) and inactive (red light).

Deactivated rules remain in the database, but have no effect on firewall behavior.

Edit rules: Clicking on the correspondent setting will open an entry window. The rule can then be modified. Click Save to save your changes.

In order to interrupt this process, click on the Cancel button.

Re-order rules: The order of the rules in the table determines the behavior of the firewall; having the correct order is essential for secure operation. By clicking the position number, you can adjust the order to suit your needs. In the drop-down menu select the Position, to which you wish to place the packet filter rule and confirm your settings by clicking on the Save button.

Delete rules: Click the trash can icon to delete a rule from the table.

Sorting the rules table: By clicking on the column headers, you can sort the table: for instance, to sort the rules by sender address, click

Source. To return to the precedence-based sorting Matching, click the column with the position numbers.

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Filters

The Filters function allows you to filter Packet Filter Rules by specific attributes. This function enhances the management of huge networks with extensive sets of rules, since rules of a specific type can be presented in a concise way.

Filtering rules:


2The entry window will open.

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Enter the filter attributes in the fields. Not all attributes must be defined.

Group: If you want to filter the rules of a specific group, select them from the drop-down menu.

State: This drop-down menu allows you to filter rules by a specific status.

Source: This drop-down menu allows you to filter rules by a specific source address.

Service: If you want to filter rules by a specific service, select it from the drop-down menu.

Action: This drop-down menu allows you to filter rules by a specific action.

Destination Port: This drop-down menu allows you to filter rules by a specific destination address.

Log: This drop-down menu allows you to filter logged rules.

Comment: If you want to filter rules by specific comments, enter the expressions in the entry menu.

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To start the filter click on the Apply Filters button.

Only the filtered packet filter rules will be displayed then. When the menu is closed, the complete set of rules will be displayed again.

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Quality of Service (QoS)

Internet Service Providers usually measure the service they provide in terms of bandwidth, measured in kBit/s. If a server tries to cross the saturation boundary – if it tries to send more information than the link can carry – the communication can either slow to a crawl or be dropped altogether.

The graphic at left, for example, shows a network with a web server and an FTP server.

Both servers share a 2Mbit uplink to the

Internet. Due to the protocols, TCP based applications (e.g., FTP) always use the full bandwidth. It might thus happen that not enough bandwidth is available for the Web Server.

The Quality-of-Service-(QoS) function allows you to assign different priorities to the connections, if the Uplink is overloaded.

These priorities are defined in the packet filter rules through the

Allow, Allow (high priority) and Allow (low priority) actions.

Important Note:

In order to enable the priorities high priority and low priority, you must select the respective interface for the QoS function in the

Network/Interfaces menu and also define the values Uplink

Bandwidth (kbits) and Downlink Bandwidth (kbits).

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In order to assign the same bandwidth to the connection with the web server, as shown in the example, as the one for the connection with the FTP server, both packet filter rules must be set to the same

Action:

1. Rule for data packets from the web server:

Source: web server

Service: HTTP

To (Server): Internet

Action: Allow (high priority)

2. Rule for data packets from the FTP server:

Source: FTP server

Service: FTP

Destination: Internet

Action: Allow (high priority)

If the Uplink is only used by the data packets of these two servers, each connection receives one half of the bandwidth (1MBit/s) in the

Worst Case. The High Priority setting becomes only relevant, if a third data connection is established. All connections with a lower priority, Allow or Allow (low priority), will be treated with a lower ranking.

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Additional Functions and Settings

Internet-wide Broadcast:

In order to drop IP broadcast packets, first define the broadcast address in the Definitions/Networks menu in the form of a new network. Next, install the appropriate packet filter rule and activate it.

1Under Definitions, open the Networks menu and define the following network:

Name: Broadcast32

Type: Host

IP Address: 255.255.255.255

Comment (optional): Enter a comment.

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Confirm the entries by clicking Add Definition.

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Under Packet Filter, open the Rules menu and enter the following rule:

Source: Any

Service: Any

Destination: Broadcast32

Action: Drop


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Segment-wide Broadcast:

For each network card configured in the Interfaces menu, the system automatically defines a network named NAME (Broadcast).

For more information, please see the Current Interface Status section of chapter on page 122.

1Under Packet Filter, open the Rules menu and enter the following rule:

Source: Any

Service: Any

Destination: Select the broadcast network for the relevant interface here.

Example: NAME (Broadcast)

Action: Drop


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4.5.2.

ICMP

ICMP Settings

This menu is used to configure the settings for Inter- net Control Message Pro-

tocol (ICMP) packets:

ICMP is used for testing network connectivity and troubleshooting network problems.

Note:

More information on ICMP can also be found in the Ping and

Traceroute sections.

ICMP on firewall and ICMP forwarding apply to all IP addresses

(Any). When ICMP on firewall is activated (green status light), all

IP addresses can ping the firewall; when ICMP forwarding is enabled, computers on the external network can ping hosts behind the firewall. Pings to single IP addresses cannot then be blocked with packet filter rules.

Important Note:

Settings configured here take precedence over rules configured in the packet filter rules table.

When the ICMP settings are disabled, packet filter rules can be used to allow specific IP addresses or networks to ping the firewall or internal network.

ICMP Forwarding: This allows you to forward all ICMP packets behind the firewall. This means, that all IPs in the local network and in all connected DMZs can be pinged.

Click the Enable button to enable the function (status light shows green).

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Important Note:

If you wish to disable ICMP forwarding, you must ensure that the

Packet Filter/Rules menu does not contain a rule of the form Any

(Source) – Any (Service) – Any (Destination) – Allow (Action).

Otherwise ICMP forwarding will remain active irrespective of the setting here.

ICMP on Firewall: The firewall directly receives and forwards all

ICMP packets. This is enabled by default /status light shows green).

Click the Disable button to change disable the function (status light shows red).

Note:

ICMP on firewall must be activated to use the Ping action. The action is described in more detail in the Network/Ping Check menu and is described in chapter on page 188.

Log ICMP Redirects: ICMP Redirects are sent from one router to the other, in order to find a better route for a destination. Router then change their routing tables and forward the following packets to the same destination on the supposed better route.

This function logs the ICMP Redirects. Clicking on the Enable button enables the function (status light is green).

Traceroute Settings

Traceroute is a tool used to check and troubleshoot network routing. This tool can resolve the path to an

IP address. Traceroute lists the IP addresses of the routers that had been used to transport the sent packet. Should the packet path not be reported within a certain time interval, traceroute will report a star

(*) instead of the IP address. After a certain number of failures, the

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Using the Security System test will end.

An interruption of the test can have any number of causes, notably a packet filter along the network path that blocks traceroute packets.

This window shows advanced options related to ICMP Traceroute.

The settings here can also open the UDP ports UNIX Traceroute uses.

Firewall is Traceroute visible: When this function is enabled, the firewall will respond to Traceroute packets.


Firewall forwards Traceroute: When this function is enabled, the firewall will forward Traceroute packets.


Note:

These two functions, Firewall is Traceroute visible and Firewall

forwards Trace route, are probably only useful when both are enabled.

Traceroute from Firewall: The Traceroute command can be used on the firewall.


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Ping Settings

This window contains configuration options specific to

ICMP Ping.

Further information about Ping can be found in chapter on page 188.

Firewall is ping visible: When this function is enabled, the firewall will respond to Ping packets. Click the Enable button to enable the function (status light shows green).

Firewall forwards Ping: When this function is enabled, the firewall will forward Ping packets. Click the Enable button to enable the function (status light shows green).

Ping from Firewall: The Ping command can be used on the firewall.


4.5.3.

Advanced

Connection Tracking Helpers

The Stateful Inspection

Packet Filter and the NAT function are provided by the

iptables module in the Net-

filter sub-system. All connections, operated with the packet filter, will be tracked by the Conntrack module: this is referred to as Con-

nection Tracking.

Some protocols, such as FTP or IRC require several communication channels, which cannot be connected through port numbers. In order to use these protocols with the Packet filter, or to replace an address through NAT, the Connection Tracking Helpers are required.

Helpers are structures, referring to so-called Conntrack Helpers.

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Generally speaking these are additional Kernel modules that help the

Conntrack module to recognize existing connections.

For FTP data connections, a FTP Conntrack helper, for example, is necessary. It recognizes the data connections, belonging to the control connection (normally TCP Port 21), which can have any destination port and adds the respective expect structures to the expect list.

The following protocols are supported. By default, all Helper modules are loaded:

• FTP

• H323

• IRC (for DCC)

• MMS (Microsoft Media Streaming)

• PPTP

Loading Helper Modules: By default, all Helper modules are loaded.

The helper modules are loaded and deleted in the selection field.

A description of how to use the selection fields can be found in chapter on page 31.

SYN Rate Limiter

Denial-of-Service attacks

(DoS) on servers, shall deny the service access to legitimate users. In the simplest case, the attacker overloads the server with useless packets, to overload its performance. Since a large bandwidth is required for such attacks, more and more attackers start using so-called SYN-Flood attacks, which don't aim at overloading the bandwidth, but at blocking the system resources. For this purpose, they send so-called SYN packets to the TCP port of the service, i.e. in a web server to Port 80.

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The SYN Rate Limiter function reduces the number of SYN packets, sent to the local network. This is disabled by default (status light shows red).


Protocol Handling

Strict TCP Session Hand-

ling: To secure a reliable data transport, the Transmission Control Protocol (TCP) that is in the transport layer is used.

TCP then creates computer to computer connections and continues to send data, until it receives an affirmative answer that the data have been transmitted. This type of connection is called TCP Handshake and is executed in three steps. Before a client is able to exchange data, with a server, for example, he sends a TCP packet, in the header of which there is also a so-called SYN-Bit (sequence number).

This is an order to the server, to set up a connection. In addition, the client transmits the so-called window size. This value defines the maximum number of bytes for the usable data in the data package, so that they can be processed on the client. In the second step the server replies by setting an ACK-Bit (Acknowledge) to the header and also transmits the window size. In the last step, the client accepts this with the ACK-Bit and starts to send the data themselves.

The firewall accepts PSH packets without having received a TCP

Handshake. This is necessary, if, for example after a Restart of the

Internet security system or after a transfer of the second firewall system with a High-Availability system the existing connections shall be maintained.

If the Strict TCP Session Handling function is enabled, the connection set-up is done by TCP Handshake.

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Validate Packet-Length: The Packet Filter checks the data packets for minimal length if the icmp, tcp or udp protocol is being used.

The minimal data lengths for the individual protocols are:

• icmp: 22 bytes

• tcp: 48 bytes

• udp: 28 bytes

If the data packets are shorter than the minimal values, they are blocked and recorded to the Packet Filter log file with the annotation

INVALID_PKT:.

The log files are administered in the Local Logs/Browse menu.

Logging Options

Log Unique DNS Requests:

DNS packets, which are sent to or through the Firewall and receive a DNS request are recorded to the Packet Filter log file with the annotation DNS_REQUEST:.


Log FTP Data Connections: All FTP data connections – either in the

active or in the passive mode – are recorded to the Packet Filter log file with the annotation FTP_DATA:.


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System Information

Packet Filter Live Log: The

Packet Filter Live Log monitors the packet filter and NAT rules in place on the Security system. The window provides a real-time display of packets intercepted by the packet filter. This is especially useful in troubleshooting and debugging packet filter rules. If, after the security system starts, a networked application, such as online banking, is not accessible, the

Packet Filter Live Log can help you reconstruct which packets are being blocked by the packet filter.

By clicking on the Show button, a new window will appear. This window displays rules violations in the order of their occurrence in real time and in table form. The background color allows you to see which action has been performed for the respective violation of a rule:

• Red: The package was dropped.

Packages that have been blocked due to the Spoof Protection,

Validate Packet Length and SYN Rate Limiter functions also have a red background color.

• Yellow: The package was rejected.

• Green: The package was allowed through.

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Setting/Resetting the Live Log Filter:

With the help of the IP Address/Netmask and Port entry fields and of the Protocol drop-down menu, you can configure the Packet Filter

Live Log such that only violations of rules with specific attributes are displayed in the table. The filter influences violations of rules that are logged after enabling this function. The filter is enabled by clicking on the Set button.

To reset the filter, click the Clear button. From this moment on, all violations of rules will be displayed in the Packet Filter Live Log again.

Clicking on the Pause Log check box interrupts or continues the update.

Note:

Please note that only those processed rules will be filed in a protocol, for which the Log function has been enabled under Packet Filter/

Rules!

Current System Packet Filter Rules: The Current Packet Filter

rules window provides detailed information for expert administrators.

The table shows all rules in real time, including system generated ones, and is taken directly from the operating system kernel.

Current System NAT Rules: As with the current filter rules,

Current NAT rules displays all user- and system-defined NAT rules.

Connection Tracking Table: This menu shows a list of all current connections and the connection parameters.

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4.6. Application Gateways (Proxies)

While a Packet Filter filters packets at the network level, Proxies

(also called Application Gateways) offer control and security at the application level by preventing a direct connection between client and server.

Each Proxy can also provide further security services for its service.

Since each proxy knows the context of its service, extensive security and protocol options are being offered. This intensive protocol analysis is made possible by well-defined and well-supported protocol standards. The proxies concentrate on the most essential information.

In the Proxies tab, select the Proxies with the same name and configure the settings. By default, all proxies are disabled. This security system contains proxies for HTTP (Web), DNS (Name server), SOCKS (point-to-point connections), POP3, SMTP (e-mail), and Ident.

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4.6.1.

HTTP


The HTTP menu allows you to configure the security system as a HTTP Caching

Proxy. This proxy can provide caching services in addition to simple proxy services, resulting in dramatic performance increases: because the system can store a copy of often-visited pages locally, these pages do not need to be loaded across the Internet.

Note:

WebAdmin should not be used through a proxy. Configure your browser so that connections to the security system’s IP address do not use a proxy server.

Disabling Netscape Communicator, Proxy:

1In Netscape, open the Edit/Settings/Advanced/Proxies menu.

2Under Manual Proxy Configuration click Show.

237.

In the No Proxy for this address field, enter the IP address of your security system.

238.

Click OK to save your changes.

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Disabling Proxy Use with Microsoft Explorer:

1In Explorer, open the Extras/Internet Options menu.

2Choose the Connections tab.

239.

Open the LAN Settings/Advanced menu.

240.

Under Exceptions, enter the IP Address of your security system.

241.

Click OK to save your settings.

The HTTP proxy controls web transactions using the HTTP protocol

(usually TCP/IP Port 80). Please note that some web servers transmit some data, in particular streaming video and audio, over a port other than 80. These requests will not be noticed when the proxy is in

Transparent mode: to support such requests, you must either use a different mode, or enter an explicit rule in the Packet Filter/Rules allowing them.

Example:

Source: a local network

Service: service with target address (the service must first be defined in the Definitions/Services menu)

Destination: IP address of the web server (or Any)

Action: Allow

HTTPS (TCP/IP Port 443) data is passed directly through the security system without processing.

Note:

In order to use the Proxy in Standard mode, the client Browser must be configured with the TCP/IP Address of the security

system and the proxy port configured in the Proxies/HTTP menu.

In addition, the HTTP proxy service requires a valid Name server

(DNS). Without configuring the client browser, the Proxy can only be used in Transparent mode.

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Global Settings

Operation Modes:

Standard: In this mode, you must select all networks which should be allowed to use the HTTP proxy service. If a browser on a nonconfigured network is configured to use the proxy, it will have no access to HTTP services.

If a browser on a non-proxied network is not configured to use the proxy, an appropriate packet filter rule can allow (un-proxied) access to HTTP services.

Example:

Source: IP address of a local client

Service: HTTP

Destination: IP address of the web server or Any

Action: Allow

To use the proxy, configure the client browser proxy settings to use the IP address of the security system and port 8080.

Transparent: In this mode, the system notices HTTP requests on the internal network, automatically processes them, and forwards them to the remote server. The client browser is entirely unaware of the proxy server. The advantage of this mode is that no additional administration or configuration is required on the client; the disadvantage is that only pure HTTP (port 80) requests can be forwarded.

All networks allowed to use the transparent proxy must be explicitly listed in the Allowed Networks menu. When Transparent mode is used, the client browser settings cannot be used to control proxy settings. Moreover, no data can be downloaded from a FTP server in this mode. HTTPS connections (SSL) must be executed via a Packet

Filter.

User Authentication: This mode complies with the functions of the

Standard mode. In addition, user access to the HTTP proxy is only authorized after previous Authentication.

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Active Directory/NT Domain Membership: This mode is only available if you have selected the Active Directory/NT Domain

Membership authentication method in the menu.

If this operation mode is set, only those users are allowed to access the HTTP-Proxy, who belong to a corresponding group (e. g.

htt_access) on the Domain Controller.

In the Content Filter window also the Profile Order/Activation function will be displayed.

To give Internet access to a user, he must be assigned to a specific profile in the Profiles-table. If you have already defined the group in your Active Directory (AD) you must give the same name to the profile (e. g. http_access) as to the group in the tab service. Like that, you only need to define those profiles for the user group, for which the access to specific websites shall be prevented.

Configuring Surf Protection Profiles is described in chapter on page 229.

Note:

Changes in Proxies become effective immediately, without further notice.

Enabling the HTTP Proxy:

1In the Proxies tab, open the HTTP menu.

2Enable the proxy by clicking the Enable button in the Global

Settings window.


242.

In the Operation mode drop-down menu, select the mode to use.

Note again that some modes require client-side configuration.

The modes are described in chapter "Operation Modes“.

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Having set the Standard or Transparent mode, continue with step .

243.

If you have selected the User Authentication mode from the

Operation mode drop-down menu, define the authentication method to use here in the User Authentication window.

Authentication Methods: Only those authentication methods that you have configured in the Settings/User Authentication menu are available here.

If you have configured the Local Users method, use the

Allowed users selection menu to choose users allowed to use the proxy. Local users are defined in the Definitions/ Users menu.

244.

In the Log level drop-down menu, choose the appropriate level of logging.

Full: All relevant information is recorded.

Access Log only: The log only records access information, for example URL accessed and username/IP address of the client.

None: No information about the proxy use is recorded.

245.

The Anonymity drop-down menu allows you to choose how much information about the client is passed on to the remote server in HTTP Request Headers.

Standard: The following headers are blocked: Accept-Encoding,

From, Referrer, Server, WWW-Authenticate and Link.

None: Client headers are not changed at all.

Paranoid: All headers except those listed below are blocked.

Additionally, the “User-Agent” field will be changed so that no information about the internal client is available.

Allow, Authorization, Cache-Control, Content-Encoding, Content-

Length, Content-Type, Date, Expires, Host, If-Modified-Since,

Last-Modified, Location, Pragma, Accept, Accept-Language,

Content-Language, Mime-Version, Retry-After, Title, Connection,

Proxy-Connection and User-Agent.

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Note:

In Standard and Paranoid modes, the proxy blocks all cookies.

If you wish to use cookies, you should use the none mode.

246.

Use the Allowed networks selection menu to select which networks should be allowed to use the proxy.

A description of how to use the selection field tool can be found in chapter on page 31.

All settings take effect immediately and will be saved if you leave this menu. Only the HTTP proxy can be accessed from the allowed networks.

See also the functions in the Advanced window.

Parent Proxy

The Parent Proxy function is required in those countries, in which an Internet access is only permitted with a statecontrolled proxy. This applies to many countries in Africa or

Asia. Once, a Parent Proxy has been defined in this window, the

HTTP requests are at first sent to the relevant IP address.

Defining a Parent Proxy:

1In the Proxies tab, open the HTTP menu.

2Enable the proxy by clicking the Enable button in the Parent Proxy window.

An advanced entry window will open.

247.

Define the Parent Proxy.

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Host: Select the parent proxy server from the drop-down menu.

Prior to this, the server must be defined in the Definitions/

Networks menu.

Service: Select the service from the drop-down menu. Prior to this, the service must be defined in the Definitions/Networks menu.

248.

Save your settings by clicking on the Save button.

249.

If an authentication is required for the Parent Proxy, click on the Enable button.

Username: Enter a user name in the entry field.


250.

Save your setting by clicking on the Save button.

Advanced

Caching: This function buffers often-used Websites to the HTTP Proxy Cache.

This is enabled by default

(status light shows green).

Clicking on the Disable button disables this function.

Block CONNECT Method on HTTP Proxy: All HTTP connection requests will be blocked by the HTTP proxy. Only the HTTP methods

GET and PUT will be allowed through the proxy. This involves that no

HTTPS connections can be established!

Each Client Request will be introduced through the information of the method. Methods define the respective action for requests. The current HTTP-specification offers eight methods: OPTIONS, GET,

HEAD, POST, PUT, DELETE, TRACE and CONNECT. Only the GET and

PUT methods are explained in this section.

The GET method is used with requests from a document or another

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Using the Security System source. A source in this case is defined through the request-URL.

There are two types: Conditional GET and partial GET. With the conditional-GET-type the request of data depends on certain conditions. The detail of these conditions is stored in the header-field

Conditional. Often used conditions are for example If-Modified-Since,

If-Unmodified-Since or If-Match. This condition helps to considerably reduce network utilization, since only the necessary data are forwarded. In practice, proxy servers, for example, use this function to prevent that data that are already stored in cache are forwarded several times. Also the partial GET-method has the same purpose. It uses the range-header-field that only forwards parts of the data, which, however, cannot be processed by the client yet. This technique is used for the resumption of an interrupted data transfer.

The PUT method allows for a modification of existing sources and/or for the creation of new data on the server. In contrast to the POSTmethod, the URL in the PUT-request identifies the data sent with the request and not the source.

Clicking on the Enable button enables the function (status light is green).

Allowed Target Services: Use the Allowed target services selection menu to choose services that the HTTP proxy should be allowed to access. By default, the services with the ports are already available, to which a connection is considered as being safe.

TCP Port: Enter the TCP/IP-Port in the entry field. By default, this is set to the TCP/IP-Port 8080.

Clear HTTP Proxy Cache: The HTTP Proxy Cache proxy stores a copy of often-visited pages locally, reducing load times.

By clicking the Start button, the cache will be cleared, and any new accesses will be loaded from the remote Internet site.

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4.6.1.1.

Content Filter (Surf Protection)

The Surf Protection Pro-

files function allows you to produce profiles, which prevent access to certain websites. These profiles can then be associated with certain users or networks, thus allowing control over which sites users may access. The categories are based on the URL data base from Cobion Security Technologies and can be edited in the Surf Protection Categories table.

Each Surf Protection Profile additionally contains a Content Filter with protection mechanisms.

Those protection mechanisms are:

• Virus Protection (VP)

• Embedded Object Filter

• Script Content Filter

This Surf Protection option can only be configured when the HTTP proxy is enabled.

Important Note:

The Content Filter connects to Cobion via Port 6000.

Whitelist Domains: A Whitelist with domains that are basically excluded from the Surf Protection option can be defined in the

Control List.

The functions of the Control List are identical to the Ordered List and described in chapter on page 34.

Surf Protection Categories

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The Surf Protection option contains 17 defined

Protection

Surf

Categories. The categories are based on the URL data base from Cobion Secur- ity Technologies and can be edited in this table.

Editing Surf Protection Categories:

1Enable this option by clicking the Enable button in the Content

Filter (Surf Protection) window.


251.

Click the Show/Hide button to open the table with the categories.

The name of category is displayed in the Name field. This name will be selected later from the Profiles Table. The Subcategories field lists the subcategories.

252.

Now click on the entry, you wish to edit.

Clicking on Name opens another entry window. If you click on the subcategories, another selection window will open. All available subcategories will be listed in this selection field.

230


Save your changes by clicking on the Save button. To keep an entry, click cancel.

253.

To close the table, click on the Show/Hide button.

The Surf Protection Categories window will close.

The Profiles Table

Each Surf Protection Profile will be displayed in the Profiles table through a separate line: The different settings will either be displayed as alphanumeric signs or as symbols. All settings can be edited by clicking on the correspondent field.

A Surf Protection Profile contains two function groups: The Surf

Protection Categories with the additional functions Blacklist, White-

list and Content Removal, and the Content Filter. The Surf Pro-

tection Categories prevent the access to Websites with a specific content. The Content Filter contains a Virus Protection function and filters Websites with specific technical components.

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The Functions

The following picture shows a Surf Protection profile:

The functions from the left to the right are:

Deleting Profiles ( ): Click on the trashcan icon to delete a profile from the table.

Name: This is the name of the Surf Protection Profile. This Name is necessary to assign this profile to a specific Network or User.

Open the editing window by clicking on the field with the entry (e.g.,

Default). Save your changes by clicking on the Save button. To keep an entry, click cancel.

URL Whitelist: This is an additional function from the Surf Pro-

tection Categories. With this access control list you can "allow" the access to specific Websites with a content that matches the subjects in the Surf Protection Categories.

Example: If you have chosen the Information and Communi-

cation subject in the Surf Protection Categories menu, but wish to explicitly allow access to a specific information website, simply add this address to the Whitelist.

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Open the access control list by clicking on the field with the entry (e.g., 0 entries).

Enter the Internet addresses one beneath the other into the entry field (e.g., www\ .

corporation\.org). Comments must be identified with a # sign at the beginning of each by clicking on the Save button. To keep an entry, click cancel.

URL Blacklist: This is an additional function of the Surf Protection

Categories. With this access control list you can "forbid" the access to specific Websites with a content that doesn't match the subjects in the Surf Protection Categories.

Open the access control list by clicking on the field with the entry

(e.g., 0 entries). Enter the Internet addresses one beneath the other.

Comments must be identified with a # sign at the beginning of each line.


Surf Protection Categories: In this field, choose the kinds of websites to which access should not be allowed.


(e.g., 0 entries).

The Surf Protection option contains 17 defined Surf Protection

Categories. Those 17 categories are administered and edited in the same table.

The administration of the Surf Protection Categories is described on page 230.

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Embedded Object Filter: This function deletes embedded objects such as ActiveX, Flash or Java from the incoming HTTP traffic.

Security Note:

Enable the Embedded Object Filter function only, if high security demands apply to your network.

Clicking on the symbol enables ( ) and disables ( ) the Em-

bedded Object Filter.

Script Content Filter: This function deletes script contents, such as

Java and VBScript from incoming HTTP traffic.

Security Note:

Enable the Script Content Filter function only, if high security demands apply to your network.

Clicking on the symbol enables ( ) and disables ( ) the Script

Content Filter.

Content Removal: This is an additional function of the Surf Pro-

tection Categories. This access control list allows you to filter Web pages that contain specific expressions. Such texts, which contain an expression from the access control list, will be replaced by a HTML comment.


(e.g., 0 entries). Enter the expressions one beneath the other.

Comments must be identified with a # sign at the beginning of each line.


Virus Protection: This functions checks incoming traffic for dangerous content such as viruses.

Clicking on the symbol enables ( ) and disables ( ) the Virus

Protection.

Enabling Surf Protection, adding Profiles:

234


1Enable this option by clicking the Enable button in the Surf

Protection (Content Filter) window.


By Default the Profiles table contains a Blank Surf Protection

Profile.

254.

To add a new Blank Surf Protection Profile to the table, click on the Add blank Profile button.

There you can edit the Surf Protection Profile.

Editing Surf Protection Profiles:

1.

In the Profiles table go to the Surf Protection Profile that you wish to edit.

2.

In the Name field enter a descriptive name for the Surf

Protection Profile.

255.

Now make the settings for the Surf Protection Categories functional group in the following order.

Surf Protection Categories: In this field, choose the websites topics to which access should be blocked from your network.

URL Whitelist: In the access control list enter those Internet addresses, for which you wish to "allow" access, even though their topic matches a topic in the Surf Protection Categories field.

URL Blacklist: In the access control list enter those Internet addresses, for which you wish to "forbid" access, even though their topic doesn't match a topic in the Surf Protection Categories field.

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Security Note:

In the HTTP protocol the header of the request will be filtered by the HTTP Cache Proxy Squid.

This is different in the HTTPS protocol - in this case, the squid does not read the header of the request, but performs a pass through. Therefore, the requested URL is unknown and cannot be filtered again. This means that the

Surf Protection option cannot block URLs on the basis of

White- or Blacklists for HTTPS connections.

Content Removal: In the access control list enter those expressions that should be deleted from the Web pages.

256.

Make the settings for the Content Filter functional group.

Embedded Object Filter: Clicking on the symbol enables ( ) and disables ( ) the filter.

Security Note:

Enable the Embedded Object Filter function only, if high security demands apply to your network.

Script Content Filter: Clicking on the symbol enables ( ) and disables ( ) the function.

Security Note:

Enable the Script Content Filter function only, if high security demands apply to your network.

Virus Protection: Clicking on the symbol enables ( ) and disables ( ) the function.

The Surf Protection Profile is now edited. Now assign the profile in the Profile Assignment table to a Network or to a Local User.

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The Profile Assignment Table

The Surf Protection Profiles from the Profiles table are assigned to

Local Users or Networks in the Profile Assignment table.

To assign a Surf Protection Profile to a local user, the HTTP proxy must be used in the User Authentication Mode. The assignment of

Profiles to a network is possible in every operation mode.

Important Note:

If you are simultaneously assigning a Profile to a local user and to a network, this Profile will only take effect, if the user accesses the

HTTP proxy from the "configured“ network! Only one Surf Protec-

tion Profile can be configured for each user or network.

If you have configured the User Authentication configuration mode in the Global Settings window, the Profile Assignment via dropdown menu will be displayed above the Profile Assignment table. By default this is set to Local Users + Network blocks.

If you have configured a Radius or LDAP-Server in the System/User

Authentication menu, they will be displayed in the drop-down menu.

Once you have selected one of the servers, the Profile Assignment table will be masked.

If you have configured the Active Directory/

NT Domain Member-

ship user authentication in the System/User

Authentication menu and have configured the corresponding operation mode in the Global Settings window, the

Profile Order/Activation hierarchy field will be displayed above the

Profile Assignment table. Clicking on the corresponding check box enables the Profile. The buttons in the right column allow you to

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Using the Security System change the order of the groups. The buttons are described in more detail in chapter on page 34.

The Functions

The following picture shows a Profile assignment:


Deleting Profile assignments ( ): Click the trash can icon to delete an assignment from the table.

Position number: The workout sequence will be displayed in the table through the respective Position number.

Clicking on the field with the entry will open the drop-down menu.

This drop-down menu allows you, to change the order of the profile assignments. Save your changes by clicking on the Save button. To keep an entry, click cancel.

Status light: The status light refers to the status of the profile assignment: Each new assignment is not yet enabled (status light is red).

The profile assignment will be enabled by clicking on the status light

(status light is green).

Profile Name: Select the Surf Protection Profile in this field from the Profiles Table.

Clicking on the field with the entry opens the drop-down menu. Save your changes by clicking on the Save button. To keep an entry, click

cancel.

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Assigned local Users: Select the local user from this field.

Clicking on this field with the entry opens the selection field. Save your changes by clicking on the Save button. To keep an entry, click

cancel.

Important Note:

If you are simultaneously assigning a Profile to a local user and to a network, this Profile will only take effect, if the user accesses the

HTTP proxy from the "configured“ network! Only one Surf Pro-

tection Profile can be configured for each user or network.

Assigned Network Blocks: Select the Network from this field.

Clicking on this field with the entry opens the selection field. Save your changes by clicking on the Save button. To keep an entry, click

cancel.

Assigning Surf Protection Profiles:

By default, the table contains already a Blank Assignment. If this blank assignment has not been edited yet, continue with step .

1By clicking on the Add blank Assignment button, add a new blank assignment.

2From the Profile Name field, select the Surf Protection Profile.

257.

From the Assigned local Users field, select the local user for this profile.

258.

From the Assigned Network Blocks, select the network for this profile.

259.

Enable the profile assignment by clicking the status light.

The status light is green.

If a user or computer defined in the profile attempts to access a blocked website, access will be blocked, and the user will receive a message explaining why.

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Skip Image Scanning: In order to enhance the performance of the Virus

Protection option, specific contents of Websites can be excluded from the control: In the current version these are images in GIF and

JPEG format. The chance that these components are infected with a virus is very low. Whereas the performance of the option can be increased by up to 25%.

Clicking on the Enable button, enables this function.

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4.6.2.

DNS

The DNS Proxy service allows you to provide internal clients with a secure and efficient name server service. If you select multiple remote name servers, they will be queried in the order they are entered.

The DNS entries in network definitions are resolved every minute by the DNS resolver. If now a DNS entry refers to a Round-Robin-DNS, the definition can be actualized every minute. The Round-Robin-DNS process offers an easy opportunity to distribute user requests to individual servers, such as to a server farm. With the Round-Robin-

DNS, the IP addresses of all servers of the server farm are assigned to a hostname in the Domain Name Service (DNS). If clients now request the IP address of this hostname there, the DNS sequentially reports these IP addresses back. Thus, a distribution of the client requests to the respective servers is achieved.

The disadvantage of the Round-Robin process is that neither a failure nor the utilization of the individual servers is accounted for.

If no name servers are entered in the Forwarding Name Servers menu, the proxy will use the Internet-wide ROOT name servers. If you or your ISP runs a name server that is closer, you should enter its

IP address here. This means, however, that they are usually slower than closer name servers.

The ROOT name servers are an integral part of the Internet. 15 ROOT name servers are distributed worldwide and are the basic instance for all secondary name servers.

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Tip:

Even if you do not plan to use the DNS proxy, you should enter the address of your provider’s DNS server address as a forwarding server. Those will be used by the firewall itself, even if the proxy is disabled. This contributes to the discharge of the root name server and the firewall produces only local queries, which generally receive faster replies.

Configuring the DNS Proxy:

1In the Proxies tab, open the DNS menu.

2Click the Enable button to start the proxy.


260.



Interfaces to listen on: Select which network cards the DNS proxy server should be reachable on. This should usually only be the internal network cards.

Network cards are configured in the Network/Interfaces menu. Further information is available in chapter on page 122.

Allowed Networks: Select which networks should have access to the proxy server.

Security Note:

In the Allowed networks menu, do not select Any unless absolutely necessary. If any is selected, the DNS Proxy can be used by any Internet user.

Forwarding Name Servers: Enter the IP addresses of your name server here.

Click Add to add each name server to the list.

Ordered Lists are described in chapter on page 34.

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All settings take effect immediately and will be saved if you leave this menu.

4.6.3.

SOCKS

SOCKS is a generic proxy, used by many client applications. Examples include

Instant Messaging Clients such as ICQ or AIM, FTP clients, and RealAudio.

SOCKS can build TCP connections for client applications, and can also provide incoming (listening) TCP and UDP ports. This is especially important for systems using NAT, as SOCKS mitigates the drawbacks of having all internal clients use the same external address. This security system supports the protocols SOCKSv4 and SOCKSv5.

Please note, however, that the SOCKSv4 protocol does not support

User Authentication.

Note:

If you wish to use SOCKSv5 with name resolution, you must also activate the DNS proxy service.

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Configuring the SOCKS Proxy:

1In the Proxies tab, open the SOCKS menu.

2Click the Enable button next to Status to start the proxy.


261.



Allowed Networks: Here you can select the networks and hosts that should be allowed to use the proxy.

All settings take effect immediately and will be saved if you leave this menu.

SOCKS-Proxy with User Authentication:

If you have enabled the User Authentication function, proxy users must use a username and password to log into the SOCKS proxy.

Because only SOCKSv5 supports User Authentication, SOCKSv4 is automatically disabled.

The Authentication Methods selection menu allows you to select the user authentication method to be used. Only those authentication methods, you have configured in the Settings/User Authentication menu are available here. If you choose to use the Local Users method, you can select which local users may access the SOCKS

Proxy.

Local Users are managed in the Definitions/Users menu.

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4.6.4.

POP3

Office Protocol 3: This is a protocol, which allows the retrieval of e-mails from a mail server. POP3 is the logical opposite of SMTP.

SMTP stands for Simple Mail

Transfer Protocol. This protocol is used to deliver emails to a mail server.

This menu allows you to configure the POP3 Proxy for incoming e-mails. The POP3 proxy works transparently, requiring no configuration on the client side.

POP3 requests coming from the internal network on port 110 are intercepted and redirected through the proxy. This process is not visible to the client. The advantage of this mode is that no additional administration or configuration is required on the client of the end user.

Configuring the POP3 Proxy:

Normally, the POP3 proxy must only be enabled in order to process

POP3 requests, as it proxies for all networks by default. The

Configured Proxied Networks displays which networks are to be allowed.

If only POP3 requests from certain networks should be forwarded, the configuration must be changed. Note that the drop-down menus contain only those networks you have already defined in the

Definitions/Networks menu.

Example: POP3 queries from the subnet

192.168.0.0/ 255.255.0.0

to pop.yoursite.com

should be forwarded through the proxy. These networks must first be defined in the Networks menu. Once this is done, continue as follows:

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1In the Proxies tab, open the POP3 menu.

2Click the Enable button next to Status to start the proxy.


262.

In the Proxied Networks window, choose the networks that the proxy should intercept requests from and to.

Source: Choose the source address here.

Example: The name of the

192.168.0.0/255.255.0.0

network.

Destination: Choose the destination address here.

Example: The name of the pop.yoursite.com

network.

263.

Confirm your selection by clicking Add.

Content Filter

Virus Protection: This option scans e-mails and attachments passing through the proxy for dangerous contents such as viruses or

Trojan horses. The results of the scan are inserted into a header of the message. Any

Proxies/Proxy Content

Manager menu. Enable the Virus Protection by clicking on the

Enable button (status light is green). messages blocked by the proxy will be shown in the

Spam Protection: This option heuristically checks incoming e-mail for characteristics suggestive of spam. This system uses an internal database of heuristic tests and characteristics, making the test independent from sender information, and also more reliable.

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Important Note:

When you use an upstream firewall, it must allow traffic from the security system to the Internet on the following ports. They are used for communication to the Spam Protection databases:

TCP Port 2703, UDP Port 6277, UDP Port 53 (DNS)

Two Thresholds can be defined for the Spam Score. This ensures that potential SPAM e-mails are treated differently by the Firewall.

Default settings:

Thresholds

Pass when Score exceeds: 03 (aggressive)

Quarantine when Score exceeds: 05 (reasonable)

The first threshold implicates that e-mails from level 3 on are filtered, but allowed through. With the help of the attached Header the e-mail on the mail-server or in the e-mail-program of the recipient can be sorted or filtered. For the second threshold the e-mail will be accepted but put into quarantine.

Basically, the Threshold with the higher level is treated more severely.

Important Note:

On busy systems, the Spam Protection may require a large percentage of system resources.

Pass/Quarantine when Score exceeds: These drop-down menus can be used to select the strategy to use in marking messages as spam. The difference between the maximum values is defined through the probability that legitimates messages, such as HTML Newsletters will be blocked. It is possible to set a value between 1 and 15 in the drop-down menu. With level 1, the e-mails are already treated with a low spam score. The following Levels serve as clue:

• Aggressive (03): This strategy will catch most spam messages.

It may also identify some legitimate messages, for example HTML newsletters, as spam.

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• Reasonable (05): This strategy is a compromise between

Aggressive and Reasonable.

• Conservative (08): This strategy will only catch messages that are highly likely to be spam. Legitimate messages are unlikely to be caught.

The following actions are preset:

• Quarantine: The e-mail will be accepted, but kept in quarantine.

The Proxy Content Manager menu will list this e-mail with status Quarantine. This menu presents further options, including options to read or to send the message.

• Pass: The proxy will add a Header to the message noting that it has found a potentially dangerous string, but will then allow the message to pass. A Header will be added to the e-mail, by which it can be sorted or filtered on the mail server or in the e-mail program of the recipient. In addition, the word *SPAM* will be added to the message subject line.

For a description of how to create rules in Microsoft Outlook

2000 please see on page 268.

The Header:

Many of the SMTP proxy functions will add headers to the messages scanned. The Header will inform the user on specific characteristics of a message. If you select the Pass action, recipients can configure their e-mail programs to filter messages with high spam scores.

The following list contains all possible Headers:

• X-Spam-Score: This header is added by the Spam Protection option. It contains a score, consisting of a numerical value and of a number of minus and plus characters. The higher the value, the more likely it is that the message is spam.

If you select the Pass action under the Spam Protection option, recipients can configure their e-mail programs to filter messages with high spam scores.

248


• X-Spam-Flag: This header is set to Yes when the proxy classifies a message as spam.

• X-Spam-Report: The proxy identified a message as spam. The added Multiline Header contains a readable and accessible antispam report.

Spam Sender Whitelist: This control list can only be defined for the

Spam Protection option. Enter the e-mail addresses of those senders into the list, whose messages you wish to allow through.

File Extension Filter: The firewall filters attachments with the extensions from the control list.

Expression Filter: This function allows to filter all e-mail texts and attached text files, that pass through the POP3 proxy by specific expressions. The expressions are defined in the check list in the form of Perl Compatible Regular Expressions.

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4.6.5.

Ident

The Ident protocol allows external servers to associate a username with given TCP connections.

While this connection is not encrypted, it is nevertheless necessary for many services.

If you enable the Ident function, the security system supports Ident queries. The system will always reply with the string that you define as Default Response, irrespective from which local service the connection will be started.

Forward Connections: Ident queries cannot be answered through

Connection Tracking. You can get around this difficulty if you use the Masquerading function: in that case, the Forward Connection function will pass the ident request on to the internal masquerading host.

Please note, however, that the actual (internal) IP address will not be released. Instead, the system will query the internal machine, and simply pass the response string to the remote server. This is often useful for internal clients with a mini-ident server, such as the ones often included in IRC and FTP clients.

250


4.6.6.

SMTP

An SMTP Proxy allows you to protect an internal mail server from remote attacks.

While forwarding and receiving messages, the proxy can also scan them for potentially dangerous contents. This menu also allows you to configure anti-

spam parameters to block unwanted e-mails.

This menu allows you to configure the POP3 Proxy for incoming e-mails. The SMTP Proxy receives all e-mails at the gateway and then forwards them to their destination. Because there is no direct contact between internal and external machines, only data are transferred, and no protocol errors will propagate. The SMTP proxy monitors the SMTP protocol on TCP port 25.

Note:

In order to use the SMTP Proxy correctly, a valid nameserver

(DNS) must be activated. System notifications are sent to the administrator even if the SMTP proxy is disabled.

251


Configuring the SMTP Proxy:

1In the Proxies tab, open the SMTP menu.

264.

Click the Enable button next to Status to start the proxy.

265.

In the Global Settings window, configure the basic settings.

Hostname (MX): Enter the hostname here.

Important Note:

If you wish to use TLS encryption, this hostname must be identical with the one listed in your DNS server’s MX record.

Otherwise, other mail servers using TLS will refuse to send incoming mails.

Postmaster Address: Enter the e-Mail address of the postmaster here.

266.

Save your settings by clicking Save.

267.

In the Allow Relay from window, select the network or hosts, which shall be allowed to send e-mails via the SMTP-

Proxy.

Security Note:

Messages sent from those networks will never be scanned by Spam Detection.

From the hosts, which are not in the Selected selection field, emails can only be sent to those domains, which are defined in the Domain Groups defined.

The basic settings are now made. E-mails can now be sent from the configured networks via the proxy.

The Domain-Groups Table

Several domains can be comprised to one group in this table (e.g.

mydomain.com, mydomain.de etc.). For each domain, and/or sub-

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Using the Security System domain a line is added to the table. They will be summarized under the group name.

The following picture shows four Domain Groups:


Deleting a Domain Group ( ): Clicking on the trash can icon deletes a domain group from the table.

Group: This is the name of the group. This group-name is required to assign a specific profile to the domain in the line.

Open the editing window by clicking on the field with the entry (e.g.

Default). Save your changes by clicking on the Save button. To keep an old entry, click Cancel.

Domain: Enter the domain into this field.

Open the editing window by clicking on the field with the entry (e.g.

Default). Save your changes by clicking on the Save button. To keep an old entry, click Cancel.

Sub-domain Inclusion: Clicking on the message in this column, allows you to integrate the sub-domains into the group.

253


Adding and editing domains:

1To enter a Blank-Domain into the table, click on the New Domain button.

Then you can edit the Domain-line.

268.

In the text entry field Group, enter a descriptive name for the domain group.

269.

Enter the domain into the Domain field.

270.

If the sub-domains are included in the group, click on the

Subdomain inclusion field.

The Profiles-and-Domain-Group-Assignment table

The following picture shows two Domain Profiles:


Domain Groups: This field allows you to select the Group Name from the Domain-Groups table.

Route Target: All e-mails for this domain-group must be forwarded to a specific host. This will normally be a host like Microsoft Ex-

change Server or Lotus Notes. Prior to that, the host must be defined in the Definitions/Networks.

You can also set the system to forward e-mails to the system specified by the MX record. You should take care that the firewall itself is not the MX host for the domain.

254


Sender Blacklist: This function allows you to create a list of sender addresses, for example those of known spam senders. The proxy will then reject all messages with these addresses in either the

From or Reply-To headers.

Enter the address data as described in the following into the control list. Open the control list by clicking on the field with the message (e.g. 0 entries).

• To block e-mails from a certain address.

Entry: [email protected]

• To block all e-mails from a certain domain.

Example: *@domain.com

• To block all e-mails from a certain user, no matter what domain is used to send the message.

Example: user@*

Comments must be identified with a # sign at the beginning of each line. Addresses, starting with this sign, will not be taken into consideration by the Sender Blacklist function!

Save your changes by clicking on the Save button. To keep an old entry, click Cancel.

The number of patterns will then be displayed in the field. If the firewall receives an e-mail from a blocked address, a 5xx error code will be issued with the message Your address (envelope or

header) is blacklisted at this site.

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Use RBL: The Realtime Blackhole Lists (RBL) function uses an external database of known spam senders to check sending addresses.

Several services of this type are available on the Internet. This function helps to massively reduce the number of spam.

One commercial service, for example, can be found at http://www.mail-abuse.org.

The Internet addresses of the data bases are entered in the Feature

Settings window into the RBL Zones control list.

The function of the Control List is identical to the Ordered List and described in chapter on page 34.

Deny RCPT Hacks: The proxy will reject e-mails with a sender address containing the characters !, %, /, or |or an additional @. In addition, addresses with an extra @ symbol, or which begin with a

dot (.) will also be blocked.

SPF Fail Check: With this function, the Firewall controls through the

Sender Policy Framework (SPF), whether ingoing e-mails have been sent from the correct server. SPF is made available through specific

DNS-entries, which are requested here. Through SPF the owners of a domain can publish information on their mail-servers in DNS.

A domain uses public Records (DNS) to direct requests for the different services (e. g. HTTP, SMTP, etc.) to those computers, which execute those services. The Mail (MX) Records are already published by all domains, to inform others on those computers, which contain e-mails for this domain. By SPF are now published the

„reverse“ Mail (MX) Records, in which it is disclosed, which computers send e-mails from a specific domain. The receiver of a mail can only control those Records and determine whether they have really been sent from this domain.

Use BATV: The Bounce Address Tag Validation (BATV) function is a tool of the standardizing body Internet Engineering Task Force

(IETF). Through domain keys the Internet Service Provider (ISP) shall be able to reject unwanted mass e-mails more easily, by

256

Using the Security System preventing that the sender address of an e-mail is concealed or falsified. Through the BATV function, an encrypted digital signature is appended to outgoing e-mails, which displays the server of the sender.

Through e-mails put into quarantine by the firewall, you will see that

40% of the Spam Mails are Bounce Mails. The appended signature allows the system to determine, whether the Bounce Mail, you have received, was originally caused by your e-mail and not through the sender of Spam Mails, who falsified the sender address. This type of

Spam Mails will then always be rejected by the firewall without the risk of false positives. In addition to that this function is used to reject all e-mails without sender address.

Please note that the signature created through BATV is valid only for seven days!

In the Feature Settings window, additional settings for the BATV function can be made.

Use Greylisting: Typically, a mail-server, using Greylisting,

will record the following three pieces of information for all incoming mail, which is also known as

Triplet.

• The sender address

• The IP

address of the host it is sent from

•

The recipient address

This

triplet

is checked against the SMTP proxy’s internal database; if the triplet has never been seen before it is created within the database getting a special time stamp

. This triplet

causes the e-mail to be rejected for a period of time of five minutes

. This action is called Greylisting. After that period of time the triplet is known and the mail will be accepted when it is sent again.

Greylisting uses the fact that most senders of Spam Mails use software, working according to the Fire-and-Forget method: Attempt to deliver the mail and if it doesn’t work, forget it! This means that senders of spam mail do not try to send mails again when there is a

257


Temporary Failures, in contrast to RFC-conforming mails-servers.

If the time stamp is older than five minutes, the e-mail will immediately be delivered and the time stamp will be updated with the current time minus five minutes

.

Verify Recipient: This function is used to compare the receiver addresses of ingoing e-mails with the addresses on your Backend Mail

Server.

To make this work, the Backend Mail Server must reject e-mails to unknown receiver addresses on SMTP-level! The general rule is: If the

Backend Mail Server rejects a mail, then the mail will also be rejected by the firewall.

Verify Sender: This function is used to check the sender addresses of incoming e-mails. It is checked whether messages can really be delivered from the sender address, by connecting to the host and executing a RCPT-command. If this is not the case the mail will be rejected.

Editing Domain Profiles:

1To add a new Blank-Profile to the table, click on the New Profile button.

Then you can edit the Profile-line.

271.

For incoming e-mails select the group from Domain Groups table in the Domain Groups field.

Open the selection window by clicking on the message (e.g.

empty).

272.

In the Route Target field, set the route for incoming mails.

Open the selection window by clicking on the message (e.g. use

MX records).

All e-mails for this domain group must be forwarded to a specific host. This will normally be a host like Microsoft Exchange

Server or Lotus Notes. Prior to that, the host must be defined

258

Using the Security System in the Definitions/Networks.

You can also set the system to forward e-mails to the system specified by the MX record. You should take care that the IPaddress of the firewall itself is not the primary MX-Record (Use

MX records) host for the domain, because it will not send e-mails to itself.

273.

In the other columns configure the Spam-Protection functions for this profile.

The functions are explained in section Profiles-and-Domain-

Group-Assignment-Table.

The Domain Profile is now assigned to a domain group and edited.

The settings will be immediately effective and without further confirmation.

Feature Settings

In the Feature Settings windows there are additional settings for the

Spam-Protection-functions in the Profiles and

Domain Group Assign-

ment table.

RBL Zones: Enter the

Internet addresses of the databases for the Use RBL function into the control list.


259


BATV Secret: The automatically generated Security Key can also be defined manually. If you use several firewalls as MX, the same

Security Key must be entered on all systems.

BATV skip Recipients: Enter the recipients that should receive unsigned messages into the control list. This is needed, for instance, when posting on mailing lists that make use of the envelope sender address. The disadvantage is that you don’t get bounces from the addresses entered in this field.

BATV skip Senders: Enter the senders that are allowed to send unsigned messages into the control list.

Greylist skip Recipients: Enter the recipients that are exempted from greylisting into the control list.

4.6.6.1.

Content Filter

Scan outgoing Messages

The Scan Outgoing Messages function uses the Content Filter for outgoing connections.

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MIME Error Checking

The MIME Error Checking module can detect errors in messages, which have been encrypted with MIME. MIME stands for

Multipurpose Internet Mail Extensions. MIME defines the structure and the composition of e-mails and of other Internet messages. This is an encoding rule, which allows for the transmission of non-text documents, e.g. pictures, audio and video in text based transmission systems. The non-text elements are encrypted at the sender and decrypted at the receiver.

The MIME Error Checking module can help detecting attacks, in which error tolerance variations in the MIME-decryption-software are being utilized.

Action: This drop-down menu allows you to select the action the proxy should take upon finding a message with a filtered string. The following actions are possible:

• Reject: The message will be bounced back to the sender with a

5xx error message and a comment. A Bounce-Mail to the sender does not contain a reason why the e-mail was blocked.

• Blackhole: The e-mail will be accepted and silently dropped. Do not use this action unless you are absolutely certain no legitimate e-mails will be lost.


The e-mail will be displayed in the Proxy Content Manger menu with the status Quarantine. This menu presents further options, including options to read or send a mail securely.

• Pass: The e-mail will be treated by the filter, but allowed to pass.

A Header will be added to the e-mail, by which it can be sorted or filtered on the mail server or in the e-Mail programs of the recipient.

A description of how the rules are created in Microsoft Outlook

2000 can be found on page 268.

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Trigger on: In this drop-down menu you define, which errors cause, that the e-mail is treated according to the Action function:

• Level 1: This step causes that only e-mails with most serious errors are treated. This setting is recommended, since many users use a deficient encryption program that already responds in the higher levels (Level 2 und 3).

• Level 2: With the exception of the e-mails with the ordinary errors, all are treated.

• Level 3: Any e-mails with errors are treated.

File Extension Filter

This module allows the firewall to selectively filter attachments based on their file extensions. The extensions to filter can be selected in the

Extensions list tool.



5xx error message. The bounce message sent to the sender will also contain an explanation of why the message was blocked.






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Extensions: Enter the file extensions, such as exe, that the firewall should filter.


Virus Protection

The Virus Protection function allows you to check e-mails and attachments for dangerous contents such as viruses, Trojan horses, and so on. The results of the scan are inserted into a header of the message.

If the Virus Protection discovers an infected e-Mail, the message will be filtered by the firewall. The further handling will be according to the setting configured in the Action drop-down menu.




• Blackhole: The e-mail will be accepted and silently dropped.


The e-mail will be displayed in the Proxy Content Manger menu with the status Quarantine. This menu presents further options, including options to safely read the message.



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Expression Filter

There is the chance that new viruses will appear which are not yet recognized by the firewall. Various viruses can be identified because of known strings – such as the IloveYou virus. The strings are entered into the control list. If an e-mail contains this string, it will be blocked.

Next to simple strings, also expressions can be defined in the form of

Perl Compatible Regular Expressions.




• Blackhole: The e-mail will be accepted and silently dropped.







Expressions: Enter the strings to filter in this list.

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4.6.6.2.

Spam Protection

This option heuristically checks incoming e-mail for characteristics suggestive of spam. This system uses an internal database of heuristic tests and characteristics.

making the test independent from sender information, and also more reliable.

Important Note:

When you use an upstream firewall, it must allow traffic from the security system to the Internet on the following ports. They are used for communication to the Spam Protection databases:

TCP Port 2703, UDP Port 6277, UDP Port 53 (DNS)

Two Thresholds can be defined for the Spam Score. This ensures that potential SPAM e-mails are treated differently by the Firewall.

The two Thresholds are equal; whereas the threshold with the higher level should be treated more severely. The functioning is explained below with the help of the default settings.

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Default settings:

Threshold One

When Spam Level exceeds: 05 (reasonable)

do this: Quarantine

Threshold Two

When Spam Level exceeds: 08 (conservative)

do this: Reject

The first threshold implicates that e-mails from level 5 on are filtered, and put in quarantine. The e-mail will be displayed in the Proxy

Content Manger menu with the status Quarantine.

With the second threshold the e-mail will be sent back with a comment.

Basically, the Threshold with the higher level is treated more severely (do this).

Important Note:

On busy systems, the Spam Detection may require a large percentage of system resources.

When Spam Level exceeds: This drop-down menu can be used to select the strategy to use in marking messages as spam. The difference between the maximum values is defined through the probability that legitimates messages, such as HTML Newsletters will be blocked. It is possible to set a value between 1 and 15 in the dropdown menu. With level 1, the e-mails are already treated with a low spam score. The following Levels serve as clue:

• Aggressive (03): This strategy will catch most spam messages.

It may also identify some legitimate messages, for example HTML newsletters, as spam.

• Reasonable (05): This strategy is a compromise between

Aggressive and Reasonable

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• Conservative (08): This strategy will only catch messages that are highly likely to be spam. Legitimate messages are unlikely to be caught.

do this: This drop-down menu allows you to select the action the proxy should take upon finding a message with a filtered string. The following actions are possible:







A Header will be added to the e-mail, by which it can be sorted or filtered on the mail server or in the e-Mail programs of the recipient. In addition, the word * SPAM * will be added to the message subject line.



Spam sender Whitelist: This control list is defined for the Spam

Protection function. Enter the e-mail addresses of those senders into the list, whose messages you wish to allow through.


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The Header:

Many of the functions will add headers to the messages scanned:

The Header will inform the user on specific characteristics of a message. If you select the Pass action, recipients can configure their e-mail programs to filter messages with high spam scores. The following is a list of the headers the SMTP proxy may insert:

• X-Spam-Score: This header is added by the Spam Detection option. It contains a score, consisting of a numerical value and of a number of minus and plus characters. The higher the value, the more likely it is that the message is spam.

If you select the Pass action under Spam Detection, recipients can configure their e-mail software to filter messages.

• X-Spam-Flag: This header is set to Yes when the proxy classifies a message as spam.

• X-Spam-Report: The proxy identified a message as spam. The added Multiline Header contains a readable and accessible antispam report.

• X-Infected: This header is added if a virus is detected within the message. The value of the header is the name of the virus found.

• X-Contains-File: The File Extension Filter is enabled and a mail contains an attachment with a potentially dangerous extension is found, the proxy will add this header.

• X-Regex-Match: When the Expression Filter is enabled and an e-mail contains a sequence of characters from the control list.

Creating rules in Microsoft Outlook 2000:

MS Outlook allows you to sort those e-mails, which had been filtered and subsequently been allowed to pass through the Firewall, provided that the Pass function in the Action drop down menu of the corresponding modules on the Firewall has been selected.

1Start MS Outlook.

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274.

Click on Inbox.

275.

Open the menu Tools/Rules Wizard.

276.

Click on the button New.

The Rules Wizard opens, in order to set new rules. The Rules wizard now leads you step-by-step through the configuration.

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Which type of rule do you want to create? (step 1)

Select the rule Check messages when they arrive.

Then click on the button Next.

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Which condition(s) do you want to check? (step 2)

In this window, select the condition with specific words in the

message header.

In the window Rule description click on the underlined portion of text and type the header's name into the input field Search

text. Example: X-Spam-Score


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What do you want to do with message? (step 3)

Define in this window, what has to be done with the filtered email. If for instance, you want to move the filtered e-mails to a specific folder, select the action move it to a specified folder.

With one click on Specified folder in the window Rule

description, a new menu appears. Here you can either choose an existing folder or create a new destination folder for the filtered e-mails. Example: Spam

Click OK to save the new settings in this menu.


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Add exceptions (step 4)

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The module Spam Detection heuristically checks incoming emails for certain characteristics. It therefore might be that safe messages, e. g. HTML-Newsletter are filtered. This menu allows you to define exceptions and to thus exclude e-mails, e. g.

messages of a particular sender from this rule.


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Enter a name for this rule (step 5)

Type a distinct name for this rule into the input field. In the options fields below, you can activate these rules and also apply them on e-mails, which are already in the Inbox folder. You can change your settings in the window Rule description.

Then click on the button Finish.

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Apply rules in the following order (step 6)

In the Rules Wizard you can activate or deactivate the rules by one click on the option field or execute changes.

In order to close the Rules Wizard, click on the button OK.

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SMTP Authentication

The Require TLS Connec-

tion function allows you to specify if appropriate encrypted connections should be required. TLS for incoming connections is always turned on and the proxy will use strong encryption automatically if the remote host supports this function. SMTP is generally not encrypted and can easily be read by third persons. The function should therefore be enabled.

Important Note:

Some mail servers, such as Lotus Domino, use non-standard implementations of TLS. While these servers claim to support TLS during connection negotiation, they cannot establish a TLS full session. If TLS is enabled, it will not be possible to send messages to these servers. In such situations, please contact the administrator of the mail server.

When configuring clients, please note that SPA (Secure Password

Authentication) should not be used. SPA is an alternative encryption method which is not supported by this security system. You should use an unencrypted authentication method instead, and use TLS (or

SSL) to encrypt the session.

The Authentication methods selection menu allows you to select the user authentication method to be used. Only those authentication methods you have configured in the Settings/User Authentication menu are available here.

Local users are defined in the Definitions/ Users menu.

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Advanced Settings

Trusted Hosts/Networks:

In the selection field a

Global Whitelist can be defined with reliable hosts or networks, which in this case are excluded from the following options:

• MIME Error Checking

• Expression Filter

• Sender Address Verification

• Realtime Blackhole Lists (RBL)

• Spam Protection

This implicates, that the necessary computing power for scans is reduced and that problematic hosts can be excluded from Content

Scanning.

Trusted Senders: with the hierarchical list trusted sender addresses can be excluded from the following functions:

• Greylisting

• Sender Verification

Security Note:

This function should only be used carefully, since sender addresses can easily be falsified.

Max message size: Enter the maximum message size for in- and out-bound mail messages. Normal values are 20 or 40 MB. Please note that the encoding used to transmit e-mails can make the size of the message larger than the files sent.

DoS Protection: In order to protect the security system against a

Denial of Service (DoS) attack, a maximum of 25 incoming concur-

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Using the Security System rent connections are supported. The 26 th connection will not be accepted.

By default, the DoS Protection function is enabled.

Outgoing TLS: Incoming connections are always TLS-encrypted. This function is used to strongly encrypt outgoing connections. You must first confirm that the remote host supports this function. TLS is used for encryption, not just authentication. SMTP is generally not encrypted and can easily be read by third persons. The function should therefore be enabled.

Important Note:

Some mail servers, such as Lotus Domino, use non-standard implementations of TLS. While these servers claim to support TLS during connection negotiation, they cannot establish a TLS full session. If TLS is enabled, it will not be possible to send messages to these servers. In such situations, please contact the administrator of the mail server.

Use Smarthost: If you wish to use an Upstream Smarthost to deliver messages, enable this function and enter the IP address of the smarthost here. In this case, the proxy will not attempt to deliver messages itself, but will instead forward them to the smarthost. The proxy will, however, deliver messages locally to domains defined in the Incoming Mail window.

For the Smarthost the Username and Password can be defined as an option.

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4.6.7.

Proxy Content Manager

The Proxy Content Manager menu allows you to manage all of the e-mails quarantined by the proxy, as well as those which, because of an error, the system was unable to forward.

This menu uses the following concepts to display and manage the e-mails:

ID: Every e-mail in this security system contains a unique ID. This

ID is contained in the header of the message, and is used by the system to identify messages in the log files. The ID will be displayed, when you touch the entry in the Type field with the mouse.

Type: Proxy Content Manager distinguishes between the POP3 and

SMTP types of filtered e-mail: If you touch the entry with the mouse, the Mail-ID will be displayed. Clicking on the entry opens a window with the content of the message. Thus you can safely read important messages. Messages of a length of up to 500 lines will be displayed completely.

Age: This column displays the age of an e-mail, i.e., the period of time since when the e-mail has arrived to the Internet security system.

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Status: The states of the e-mails are displayed in the Proxy Content

Manager through symbols.

• deferred ( ): The e-mail will be sent to the intended recipient.

Normally, messages of this type are forwarded soon after the proxy receives them. If, however, temporary problems delivering the message are encountered, it may remain in the queue with this status for a short while. Such messages will be delivered as soon as the destination host can be contacted.

• quarantined ( ): The e-mail will be quarantined due to the

Quarantine configuration to one of the Content Filter functions.

Unwanted or dangerous content such as a virus have been discovered in the message. Such messages will remain in the table until an administrator deletes or sends them.

On the right side, next to the status symbol for those e-mails, which are kept in quarantine, it is displayed which function blocked the message:

SP: Spam Protection

VP: Virus Protection

Filter: File Extention Filter

EXP: Expression Filter

MIME: MIME Error Checking

• permanent error ( ): The e-mail contains a permanent error.

Sender: The sender of an e-mail is displayed in this column. For the

SMTP type, this is the sender address on the envelope.

For the POP3 type, this is the address of the „From:“-header of an email. If no sender address is displayed, the e-mail contains the additional status Bounce.

If the Content Filter has blocked an e-mail which might be a Phishing

Mail, this will be indicated if you touch the cell with the VP message with the mouse.

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With Phishing Mails fraudsters lure Internet users to false websites and request the visitors to enter information on their passwords and access information on their online banking.

Recipient(s): The recipient of an e-mail is displayed in this column.

For the SMTP type, this is the recipient’s address on the enveloppe.

For e-mails with the deferred status, the delivery status will be displayed separately for each recipient: Deferred ( ) or permanent error ( ).

The drop-down menu at the bottom of the table shows further functions to manage single e-mails. Click the selection box next to an e-mail to manage it.

The following functions are available:

Delete: All chosen e-mails will be deleted.

Force delivery: All chosen e-mails will be forwarded to the recipient addresses, even those having a quarantined status. For e-mails with a deferred or permanent error status, it is being tried again to deliver the message. If the system encounters another problem delivering it, the message will return to its previous status.

Download as .zip file: The chosen e-mails are packed into a zip-file and then saved to the selected local host.

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Global Actions

In order to save disk space on the security system, you can use this option to delete all messages of a certain type. E-Mails being sent or forwarded while the system is deleting messages will not be affected.

From the Please select drop-down menu, select the type and start the action by clicking on the Start button.

If you wish to actualize the SMTP/POP3 Proxy Content table, select the Refresh proxy content table action from the Please select drop-down menu.

Attention:

Messages of the selected type will be deleted without further confirmation.

Filters

The Filters function allows you to filter E-Mails with specific attributes from the table. The function facilitates the management of huge networks, since the protocols of a specific type can be presented in a concise way.

Filtering e-mails:



283.

Enter the filter attributes in the following fields. Not all attributes have to be defined.

Type: If you wish to filter e-mails of a specific type, select them from the drop-down menu.

Status: If you wish to filter e-mails of a specific status, select them from the drop-down menu.

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Content Filter Type: This drop-down menu allows you to filter e-mails, that have been filtered by a specific function from the

Content Filter.

Sender: This drop-down menu allows you to filter e-mails with a specific sender address.

Recipient(s): This drop-down menu allows you to filter e-mails with a specific recipient address.

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Click the Apply Filters button to start the filter.

In this case, only the filtered e-mails will be displayed in the table.

Once the menu has been left, all protocols will be displayed again.

Automatic Cleanup

In order to save disk space on the security system, you can use this option to delete e-mails automatically.

Enable the function by clicking the Enable button in the Status line


Mode: Configure the mode in this drop-down menu. The following modes are available:

• Cleanup by message age: This mode deletes all old e-mails from a certain age on.

Enter the maximum age in days into the Maximum Message

Age (days) entry field.

• Cleanup by message count: As soon as there is a specific amount of e-mails, older e-mails will be deleted. By default, this is set to 500 e-mails. It shouldn’t be configured to less than 200.

Save the settings by clicking on the Save button. The action will then be executed once per hour, so that the maximum level is only exceeded for short periods.

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Daily Spam Digest

This Daily Spam Digest function causes the system to send a daily digest of the proxy content manager to the internal recipients by email, informing them which incoming emails have been put into quarantine within the last 24 hours. The notification includes a list of emails providing information on arrival time, size, sender, subject, and message-ID

(for Postmaster) sorted in inverse chronological order, beginning with the newest:

Enable the function by clicking the Enable button in the Status line


Domains: Select the domains for which the daily digest of quarantined messages should be called. All here available domains must have previously been defined on the Proxies/SMTP menu.

Skip Addresses: If you want to exclude certain members of your domain from receiving the daily digest, enter their full e-mail addresses into the control list.


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4.7. Virtual Private Networks (IPSec VPN)

A Virtual Private Network (VPN) is a secure connection between two networks over an untrusted network (such as the Internet).

VPNs are very useful when sensitive information must be transmitted or received over the Internet. The VPN prevents third parties from reading or modifying the information in transit. The connection is controlled and secured by the software installed at the connection endpoints. This software implements authentication, key exchange, and data encryption according to the open Internet Protocol Security

(IPSec) standard.

Only authenticated computers can communicate through a VPNprotected connection. No other computer can transmit information over this connection.

VPN connections can be established between two hosts, one host and one network, or two networks. When one endpoint is a single computer, the VPN connection will extend all the way to that computer, where the data is encrypted and decrypted. If one end point is a network, the connection will end at a Security Gateway, which manages the VPN functions for the rest of the network. The data transmission within the network, between the security gateway and client computers, is not encrypted.

Data transfer between two computers over a Public Wide Area

Network (WAN) uses public routers, switches, and other network components. This is, in general, not secure as messages can be read in clear text at every point between the end computers. An IPSec

VPN, however, builds a secured IP Security (IPSec) tunnel through the public WAN. Messages sent through this tunnel cannot be read.

An IPSec tunnel consists of a two directional Security Associations

(SAs), one for each direction of communication.

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An IPSec SA consists of three components:

• the Security Parameter Index (SPI),

• the IP address of the receiver,

• a Security Protocol Authentication Header (AH) or En-

capsulated Security Payload (ESP).

With the help of the SA, the IPSec VPN tunnel has the following features:

• Data confidentiality through encryption

• Data integrity through data authentication

• Sender authentication through PSK, RSA, or X.509 certificates

The security features can be combined as desired. Most administrators use at least the encryption and authentication components.

There are a few scenarios where IPSec VPNs can be used:

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1. Net-to-Net Connection

In this scenario, one network communicates with another.

Two remote offices can use a VPN tunnel to communicate with each other as though they were on a single network.

This kind of connection can also be used to allow trusted third companies (e.g., consultants and partner firms) access to internal resources.

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2. Host-to-Net Connection


In this scenario a single computer communicates with a network.

Telecommuters can use VPN to communicate with the main office securely.

3. Host-to-Host Connection

In this scenario one computer communicates with another computer.

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Two computers can use a VPN tunnel to communicate securely over an untrusted network.

A VPN server is a cost effective and secure solution for transferring sensitive data, and can replace existing expensive direct connections and private lines.

The IPSec Concept

IP Security (IPSec) is a suite of protocols designed for cryptographically secure communication at the IP layer (layer 3). (see also chapter , on page ).

The IPSec standard defines two service modes and two protocols:

• Transport Mode

• Tunnel Mode

• Authentication Header (AH) Authentication protocol

• Encapsulated Security Payload (ESP) Encryption (and Authentication) protocol

IPSec also offers methods for manual and automatic management of

Security Associations (SAs) as well as key distribution. These characteristics are consolidated in a Domain of Interpretation

(DOI).

Note:

This security system uses the Tunnel Mode and the Encapsulated

Security Payload (ESP) protocol.

IPSec

Modes

IPSec can work in either Transport Mode or Tunnel Mode. In principle, a host-to-host connection can use either mode. If, however, one of the endpoints is a security gateway, the Tunnel Mode must be

284

Using the Security System used. The IPSec VPN connections on this security system always use the Tunnel Mode.

In Transport Mode, the original IP packet is not encapsulated in another packet. The original IP header is retained, and the rest of the packet is sent either in clear text (AH) or encrypted (ESP). Either the complete packet can be authenticated with AH, or the payload can be encrypted and authenticated using ESP.

In both cases, the original header is sent over the WAN in clear text.

In Tunnel Mode, the complete packet – header and payload – is encapsulated in a new IP packet. An IP header is added to the IPpacket, with the destination address set to the receiving tunnel endpoint. The IP addresses of the encapsulated packets remain unchanged. The original packet is then authenticated with AH or encrypted and authenticated using ESP.

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IPSec-Protocols

IPSec uses two protocols to communicate securely on the IP level.

• Authentication Header (AH) – a protocol for the authentication of packet senders and for ensuring the integrity of packet data

• Encapsulating Security Payload (ESP) – a protocol for encrypting the entire packet and for the authentication of its contents.

The Authentication Header-Protocol (AH) checks the authenticity and integrity of packet data. In addition, it checks that the sender and receiver IP addresses have not been changed in transmission. Packets are authenticated using a checksum created using a Hash-based

Message Authentication Code (HMAC) in connection with a key. One of the following hashing algorithms will be used:

Message Digest Version 5 (MD5) This algorithm generates a 128bit checksum from a message of any size. This checksum is like a fingerprint of the message, and will change if the message is altered.

This hash value is sometimes also called a digital signature or a

message digest.

The Secure Hash (SHA-1) algorithm generates a hash similar to that of MD5, though the SHA-1 hash is 160 bits long. SHA-1 is more secure than MD5, due to its longer key.

Compared to MD5, an SHA-1 hash is somewhat harder to compute, and requires more CPU time to generate. The computation speed depends, of course, on the processor speed and the number of IPSec

VPN connections in use at the Security Gateway.

In addition to encryption, the Encapsulated Security Payload protocol (ESP) offers the ability to authenticate senders and verify packet contents. If ESP is used in Tunnel Mode, the complete IP packet (header and payload) is encrypted. New, unencrypted IP and

ESP headers are added to the encapsulating packet: The new IP header contains the address of the receiving gateway and the address

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Using the Security System of the sending gateway. These IP addresses are those of the VPN tunnel.

For ESP with encryption normally the following algorithms are used:

• Triple Data Encryption Standard (3DES)

• Advanced Encryption Standard (AES)

Of these, AES offers the highest standard of security. The effective key lengths that can be used with AES are 128, 192 and 256 Bits.

This security system supports a number of encryption algorithms.

Either the MD5 or SHA-1 algorithms can be used for authentication.

Key Management

The secure generation, management, and distribution of keys is crucial to the security of IPSec connections. IPSec supports both manual and automatic key distribution.

Manual key distribution requires that both sides of the connection be configured by hand. This means that for every Security

Association (SA) (there are two per tunnel), a Security Parameter

Index (SPI) must be selected, a key for encryption and authentication must be generated, and the keys must be installed on both sides of the tunnel. These keys should also be changed at regular intervals.

Clearly, manual distribution is labor-intensive. Because of the complexity of the process, manual intervention intensifies the risk that an unauthorized party gains access to the keys.

For these reasons, Manual Key Distribution is not often used.

The Internet Key Exchange (IKE) protocol provides IPSec with automatic key management capabilities. Keys are automatically generated and securely exchanged. IKE also allows the generation and management of multiple VPN tunnels and the use of dynamic IP addresses. The IKE protocol automatically manages the Security

Associations (SAs) for a connection.

This system supports three kinds of authentication for IKE:

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• IKE with Preshared Keys (PSK)

• IKE with RSA Keys (RSA)

• IKE with X.509v3 Certificates (X.509)

Authentication with Preshared Keys (PSK) uses secret passwords as keys – these passwords must be distributed to the endpoints before the connection is built. When a new VPN tunnel is built, each side checks that the other knows the secret password. The security of such

PSKs depends on how “good” the passwords used are: common words and phrases are subject to dictionary attacks. Permanent or long-term IPSec connections should use certificates or RSA keys instead.

Authentication via RSA Keys is much more sophisticated. In this scheme, each side of the connection generates a key pair consisting of a Public Key and a Private Key. The private key is necessary for the encryption and authentication during the Key Exchange. Both keys are mathematically independent from each other and are in a unique relation to each other: Data encrypted with one key can only be decrypted with the other. The Private Key cannot be deducted with maintainable work from the Public Key.

Both receivers of an IPSec VPN connection require in this authentication method their own Public Key and Private Key.

Similarly, the X.509 Certificate authentication scheme uses public

keys and private keys. An X.509 certificate contains the public key together with information identifying the owner of the key. Such certificates are signed and issued by a trusted Certificate Authority

(CA). During the Key Exchange process, the certificates are exchanged and authenticated using a locally stored CA certificate.

Further information on Certificate Authorities (CAs) can be found in chapter on page 95 and in chapter on page 309.

4.7.1.

Connections

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The Connections menu allows you to configure local settings for new

IPSec VPN tunnels and to manage existing connections.

Global IPSec Settings

This section allows you to enable or disable the

IPSec VPN system by clicking the Enable/Dis-

able button next to

Status.

IKE Debugging: This function allows you to check the IPSec connection. Detailed information is logged to the IPSec logs. These protocols can be displayed in real time in the Local Log/ downloaded to your local computer. Further information on the Local

Logs menu can be found in chapter on page 326.

Important Note:

The IKE Debugging function requires a large amount of system resources, and can slow the IPSec VPN connection building process down considerably. This system should only be enabled when IKE is actively being debugged.

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IPSec Connections

In the IPSec Connections table, all current VPN connections are listed.

IPSec System Information

VPN Status: In the VPN

Status window, status information is shown for active encryption algorithms, all active IPSec connections, and detailed information about every Security Association (SA).

VPN Routes: The VPN Routes window shows all active IPSec SA connections. If no entries exist here, no IPSec connections are active.

Routing entries follow the following form:

A B -> C => D

3 192.168.105.0/24 -> 192.168.104.0/24 => %hold

8 192.168.105.0/24 -> 192.168.110.0/24 => %trap

0 192.168.105.0/24 -> 192.168.130.0/24 =>

[email protected]

Column A: The number of packets in this VPN connection.

Column B: The local subnet or host.

Column C: The remote subnet or host.

Column D: The status of the connection.

%trap: The connection is idle and is waiting for a packet. The status initiates the end of the VPN connection.

%hold: The connection is being negotiated. All packets will wait until the VPN tunnel is established (UP).

[email protected]: Messages like these show that the tunnel is up.

A VPN tunnel with ID

0x133a

has been established, and the IP address of the Remote Endpoint is

233.23.43.1.

.

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Example:

A B -> C => D

23 192.168.105.0/24 -> 192.168.104.0/24 =>

[email protected]

This message shows that 23 data packets have been sent from network

192.168.105.0/24

to network . The tunnel’s ID number is

0x1234

, and the remote endpoint is has IP address

123.4.5.6.

.

Configuring an IPSec Connection:

1Under the IPSec VPN tab, open the Connections menu.

2Enable the option by clicking the Enable in the Global IPSec

Settings window.

The New IPSec Connection window will open.

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In the Name field, enter a descriptive name for the new

IPSec VPN connection:

Name: Enter a descriptive name for this IPSec-VPN tunnel.

Allowed characters are: Only alphanumeric and underscore characters are allowed.

Type: Choose the type of connection to use.

Use Standard for Net-to-Net connections.

The Road Warrior, Road Warrior CA and MS Windows L2TP

IPSec connection types are useful with HOST-to-NET connections, e.g. for sales representatives. The telecommuter will then be able to build an IPSec connection to the firm’s internal network. A road warrior connection can only be used through a

default gateway.

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Note:

Multiple remote key objects can be added to a single road warrior connection. This can serve to reduce configuration hassles. It must be respected, however, that all road warriors use the same type of authentication (PSK, RSA or X.509) – a mixed operation can result in malfunctions.

Further configuration parameters can be set for the chosen connection type.

286.

Make the following basic settings for the IPSec-VPN connection.

IPSec Policy: The policy controls the parameters for the VPN connection. This includes the settings for Key Exchange, IKE, and the IPSec connection.

The drop-down menu contains a number of pre-defined policies.

You can define custom ones in the IPSec VPN/Policies menu.

Note:

A standard policy is used for the MS Windows L2TP IPSec type of connection.

The configuration of IPSec Policies is detailed in chapter on page 297.

Auto Packet Filter: Once the IPSec-VPN connection is successfully established, the packet filter rules for the data traffic will automatically be added. After the completion of the connection, the packet filter rules will be removed.

The Auto Packet Filter function is available for the Standard and road warrior connection types.

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Security Note:

If you want greater control over the packet filter rules, or wish to manage them in a more centralized way, disable the Auto Packet Filter function and enter the rules manually in the Packet Filter/Rules menu.

Strict Routing: When this function is enabled (On), VPN Routing is not only done with the destination address, but in harmony with the source and destination address.

If Strict Routing is enabled, it is possible to simultaneously set encrypted and decrypted connections from different source addresses to one network.

If the Strict Routing function is disabled (Off), further networks and hosts can be connected to the IPSec-VPN tunnel through the setting of Source NAT rules.

The Strict Routing function can only be disabled or enabled in the Standard type of connection. For all other types of connections the function is always enabled!

287.

In the Endpoint Definition window, select the endpoint of the IPSec tunnel.

Local Endpoint: Use the drop-down menu to select the local endpoint. Always choose the network interface on the same side of the firewall as the remote endpoint.

Remote Endpoint: Choose the remote endpoint here.

With the Road Warrior or MS Windows L2TP IPSec types of connection, the remote endpoint has always a dynamic IP address.

288.

The Subnet definition (optional) window allows you to set an optional subnet for both endpoints.

Local Subnet: Choose the local subnet here.

Remote Subnet: Choose the remote subnet here.

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With a road warrior connection, only the local subnet can be configured. This is no more possible if you additionaly enable the

L2TP Encapsulation function in step .

Note:

With the MS Windows L2TP IPSec connection this window will not be displayed. The IPSec-VPN access will be managed through the Packet Filter.

289.

Select the associated key in the Authentication of Remote

Station(s) window.

IPSec remote keys are defined in the IPSec VPN/Remote

Key menu. The settings in this window depend on the type of connection.

7. 1 Standard

Key: Use the drop-down menu to select a Remote Key.

7.2 Road Warrior

L2TP Encapsulation: This drop-down menu allows you to additionally enable L2TP over IPSec (On).

Keys: Select the Remote Keys for the road warrior connection from the selection window.

7.3 Road Warrior CA

L2TP Encapsulation: This drop-down menu allows you to additionally enable L2TP over IPSec (On).

Use CA: With the road warrior CA connection type, the authentication is based on the Distinguished Name (DN) of the remote receiver (Remote Endpoint). You thus need a Certificate Au-

thority (CA) from this endpoint. Only the VPN Identifier X.509

DN can be used.

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From the drop-down menu, select X.509 DN Certificate

Authority (CA).

Client DN Mask: In order to use a Distinguished Name as an

ID, you will need the following information from the X.509 index:

Country (C), State (ST), Local (L), Organization (O), Unit (OU),

Common Name (CN) and E-Mail Address (E).

The data in this entry field must be in the same order as in the certificate.

7.3 MS Windows L2TP IPSec

L2TP Encapsulation: With this type of connection, L2TP over

IPSec is automatically enabled (On).

IPSec Shared Secret: With the MS Windows L2TP IPSec connection type, the authentification is based on Preshared Keys.

Enter the password into this entry field.

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Save these settings by clicking Add.

The newly configured IPSec profile will appear, deactivated, at the bottom of the table (status light is red). Clicking on the status light enables the IPSec connection.

After you configure a new VPN tunnel, you will need to establish the related packet filter rules to allow the two computers to communicate.

Configuring packet filter rules is described in chapter on page 190.

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Example:

In order to set-up a Net-to-Net VPN connection (between network 1 and network 2), you will need to define the following rules:

1Under the Packet Filter tab, open the Rules menu.

2In the Add Rules window, add the following rule for network 1:

Source: Network1

Service: Any

Destination: Network 2

Action: Allow

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Confirm the entries by clicking on Add Definition.

292.

In the Add Rules window, add the following rule for network

2:

Source: Network 2

Service: Any

Destination: Network1

Action: Allow

293.

Confirm the entries by clicking on Add Definition.

These rules will allow complete access between the two networks.

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4.7.2.

Policies


In the Policies menu, you can customize parameters for IPSec connections and collect them into a policy.

Policies are used to define

IPSec connections, and contain the configuration of the selected key ex-

change method, IKE, and the IPSec connection.

The chosen key exchange method defines how the keys for the connection are to be managed.

The two exchange methods are:

• Manual Key Exchange

• Internet Key Exchange (IKE)

Because of the complexity of manual exchange, this system only supports the IKE key exchange method. Manual exchange is not allowed.

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Configuring an IPSec Policy:

1Under the IPSec VPN tab, open the Policies menu.

2Click New to open the New IPSec Policy menu.

294.

In the Name field, enter a name for the new policy:

Name: Enter a name describing the policy. It may be useful to include the encryption algorithm in the name. The name can also be defined as the last step in creating the policy.

Key Exchange: Only IKE is supported.

295.

In the ISAKMP (IKE) Settings window, configure the settings for IKE:

IKE Mode: The IKE mode is used to support key exchange. At the moment, only the Main Mode is supported.

Encryption Algorithm: The encryption algorithm is the algorithm used to encrypt IKE connections. The IPSec VPN function of this security system supports 1DES 56bit, 3DES 168bit, AES

(Rijndael) 128bit, AES Rijndael 192bit, AES Rijndael

256bit, Blowfish, Serpent 128bit and Twofish.

Authentication Algorithm: The hashing algorithm ensures the integrity of the IKE messages. The MD5 128bit, SHA1 160bit,

SHA2 256bit and SHA2 512bit algorithms are supported. The algorithm used is determined by the remote endpoint of the

IPSec connection.

Important Note:

The SHA2 256bit and SHA2 512bit algorithms require a great deal of system resources.

IKE DH Group: The IKE group (Diffie-Hellmann group) describes the kind of asymmetric encryption used during key exchange. The IPSec VPN system on this security system supports the Group 1 (MODP768), Group 2 (MODP 1024),

Group 5 (MODP 1536), Group X (MODP 2048), Group X

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(MODP 3072) and Group X (MODP 4096) protocols. The group used is determined by the remote endpoint.

SA lifetime (secs): This option allows you to set the lifetime of

IKE sessions in seconds. This is set by default to 7800 seconds

(2h, 10 min).

In general, times between 60 and 28800 seconds (1 min to 8 hours) are allowed.

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In the IPSec Settings window, configure the settings for the

IPSec connection:

IPSec Mode: This system only supports tunnel mode.

IPSec Protocol: This system only supports ESP.

Encryption Algorithm: Choose the encryption algorithm to use here. The IPSec VPN function of this security system supports

1DES 56bit, 3DES 168bit, AES (Rijndael) 128bit, AES

Rijndael 192bit, AES Rijndael 256bit, Blowfish, Serpent

128bit and Twofish. If you wish to create IPSec connections without encryption, choose null here.

Enforce Algorithm: If an IPSec gateway makes a proposition with respect to an encryption algorithm and to the strength, it might happen, that the gateway of the receiver accepts this proposition, even though the IPSec Policy does not correspond to it. In order to avoid this, Enforce Algorithm must be enabled .

Example:

The IPSec Policy requires AES-256 as encryption. Whereas a road warrior with SSH Sentinel wants to connect with AES-128.

Without Enforce Algorithm the connection will be admitted, which constitutes a security risk.

Authentication Algorithm: The MD5 128bit, SHA1 160bit,

SHA2 256bit and SHA2 512bit algorithms are supported. The algorithm used is determined by the remote endpoint of the

IPSec connection.

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Important Note:

The SHA2 256bit and SHA2 512bit algorithms require a great deal of system resources.

SA Lifetime (secs): This option allows you to set the lifetime of the IPSec connection. This is set by default to 3600 seconds

(1h). In general, times between 60 and 28800 seconds (1 min to

8 hours) are allowed.

PFS: The IPSec key used for VPN connections is generated from random numbers. When Perfect Forwarding Secrecy (PFS) is enabled, the system will ensure that the numbers used have not already been used for another key, such as for an IKE key. If an attacker discovers or cracks an old key, he or she will have no way of guessing future keys.

The IPSec VPN system on this security system supports the

Group 1 (MODP768), Group 2 (MODP 1024), Group 5

(MODP 1536), Group X (MODP 2048), Group X (MODP

3072) and Group X (MODP 4096) protocols. If you do not wish to use PFS, select No PFS.

By default, this is set to Group 5 (MODP 1536).

Important Note:

PFS requires a fair amount of processing power to complete the

Diffie-Hellmann key exchange. PFS is also often not 100% compatible between manufacturers. In case of problems with the firewall’s performance or with building connections to remote systems, you should disable this option.

Compression: This algorithm compresses IP-packets before they are encrypted, resulting in faster data speeds.

This system supports the Deflate algorithm.

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If you have not yet named this policy, scroll back to the

Name field and enter one now.

298.

Create the new policy by clicking Add.

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The new policy will appear in the IPSec Policies table.

4.7.3.

Local Keys

The Local Keys menu allows an administrator to manage local X.509 certificates, to define the local IPSec identifier, and to generate a local RSA key pair.

Local IPSec X.509 Key

In this window, you can define local keys for X.509 certificates provided you have already generated these certificates in the IPSec

VPN/CA Management menu. Chapter on page 309 describes the process of generating X.509 certificates.

Local Certificate: Select here the certificate for the X.509 authentication This menu only contains those certificates for which the associated private key is available.

Passphrase: In the entry field, enter the password used to secure the private key.

The Active Key will appear with its name in the Local IPSec X.509

Key window. If you choose a new local key, the old key will automatically be replaced.

The security system will use the ID and public/private key pair of the current Local X.509 Key to identify, authenticate, and encrypt

X.509 IPSec key exchanges.

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RSA Authentication

For the authentication via RSA each side of the connection requires a key pair consisting of a Public Key and a Private Key. The key pair is created in two steps in the Local IPSec RSA Key window: First, the Local IPSec Identifier is defined and then the key pair generated.

1In the Local IPSec RSA Key window, define a unique VPN

Identifier.

IPv4 Address: For static IP addresses.

Hostname: For VPN security gateways with dynamic addresses.

E-Mail Address: For mobile (road warrior) connections.


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Generate a new RSA Key, by selecting the key length from the RSA Key Length drop-down menu.

Important Note:

The key length must be identical on both security systems.

Depending on the selected key length and the processor of the security solution, the generation of RSA keys can take several minutes.

300.

When you click Save, the system will begin generating a new

RSA key pair.

Then the active Public Key will be displayed in the Local Public RSA

Key window. The Public Key from this window will be exchanged with the respective end point, e.g. via e-mail.

The Public Key from the endpoint will be entered later into the

Remote Keys menu in the Public Key window. The Remote Keys menu is described in chapter on page 304.

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PSK Authentication

For authentication through Preshared Keys (PSK), in this menu no additional configuration for the local IPSec key is required!

During the key exchange using IKE Main Mode, only IPv4 Ad-

dresses are supported as IPSec identifiers. The IPSec identifier in the

IKE Main Mode is automatically encrypted with the PSK, and so PSK cannot be used for authentication. The IP addresses of IKE connections are automatically used as IPSec identifiers.

You generate the PSK Key in the IPSec VPN/Remote Keys menu.

It will automatically be used as the Local PSK Key as well.

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4.7.4.

Remote Keys

IPSec remote key objects can be administered in the Remote Keys menu.

An IPSec-Remote-Keyreceiver can either be a

Security gateway, a Host or also a Road warrior with dynamic IP-

address.

Object represents an

IPSec receiver. This

An IPSec remote key object is defined by three parameters:

• The IKE authentication method (PSK/RSA/X.509)

• The IPSec ID of the remote endpoint (IP/Hostname/E-Mail Address/Certificate)

• The authentication data (Shared secret for PSK, public key for

RSA, X.509 certificate)

New Remote IPSec Key

Every IPSec remote endpoint must have an associated IPSec remote key object defined. The new Remote-Key objects are defined in the

Remote IPSec Key window.

Defining IPSec Remote Keys:

1Under the IPSec VPN tab, open the Remote Keys menu.

The New Remote IPSec Key will be displayed.

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In the Name field, enter a name for the new Remote Key.

If you wish to use the IPSec Remote Key for a standard connection, continue with step .

Virtual IP (optional): This function allows you to assign a virtual IP address to the road warrior. This is the only way to manually set IP addresses for such connections. If you enter an

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IP address here, it must also be configured on the road warrior system.

Attention:

With a road warrior IPSec tunnel, the Virtual IP function must be enabled if you wish to use the NAT Traversal function and the L2TP Encapsulation function is disabled.

The IP address entered here should not be used anywhere else, and cannot be a part of a directly connected network.

302.

Use the Key type drop-down menu to select the IKE authentication method. Further options are available depending on the chosen Key type.

PSK: The firewall only supports using IPv4 Addresses as VPN

Identifiers during the key exchange phase of IKE Main Mode.

Enter the shared password in the Preshared Key field.

If you wish to configure many road warrior connections, you only need one PSK for all connections.

Security Note:

Use a secure password! Your name spelled backwards is, for example, not a secure password – while something like xfT35$4 would be. Make certain that this password does not fall into the wrong hands. With this password, an attacker can build a VPN connection to the internal network. We recommend changing this password at regular intervals.

RSA: The key pair consists of a private key and a public key.

In order for the endpoints to communicate, they must exchange their public keys. Public keys can be exchanged via e-mail.

In the VPN Identifier drop-down menu, choose the VPN ID type of the endpoint. If you select E-Mail Address, Full qualified

domain name or IP Address, you must enter the address or name in the entry field below.

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X509: Use the VPN Identifier drop-down menu to select the kind of VPN ID to use. If you select E-Mail Address, Full

qualified domain name or IP Address, you must enter the address or name in the entry field below.

In order to use a Distinguished Name as an ID, you will need the following information from the X.509 index: Country (C),

State (ST), Local (L), Organization (O), Unit (UO), Common

Name (CN) and E-Mail Address (E-Mail).

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To save the new IPSec remote key object, click Add.

The new remote key object will appear in the Remote Keys table.

CA Management Remote Keys are shown in a separate table.

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4.7.5.

L2TP over IPSec

L2TP over IPSec is a combination of the Layer 2 Tunneling Protocol and of the IPSec standard protocol. L2TP over IPSec allows you, while providing the same functions as PPTP, to give individual hosts access to your network through an encrypted IPSec tunnel. On

Microsoft Windows systems, L2TP over IPSec is easy to set-up, and requires no special client software.

For the MS-Windows systems 98, ME and NT Workstation 4.0,

Microsoft L2TP/IPSec VPN Client must first be installed. This client is available from Microsoft at: http://www.microsoft.com/windows2000/server/evaluation/news/bull etins/l2tpclient.asp

L2TP over IPSec Settings

Authentication: Use this drop-down menu to configure the authentication method. If you have defined a RADIUS server in the System/User

Authentication menu, you can use it here as well.

The configuration of the Microsoft IAS RADIUS server and the configuration of RADIUS within WebAdmin is described in chapter on page 66.

Debugging: This function allows you to check the L2TP-over-IPSec connection. Detailed information is logged to the IPSec logs. These protocols can be displayed in real time in the Local Logs/Browse menu or downloaded to your local computer. Further information about the Local Logs menu can be found in chapter on page 326.

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L2TP over IPSec IP Pool

This menu is used to define which IP addresses

PPTP hosts should be assigned to. By default, a network from the private IP range 10.x.x.x will be selected when the

L2TP-over-IPSec function is enabled for the first time. This network is referred to as IPSec Pool and can also be used for all other functions of the Security system, using network definitions. If you wish to use a different network, simply change the definition of the IPSec-Pool, or assign another defined network as IPSec-Pool here.

Note:

If you use private IP addresses for your IPSec Pool, such as the predefined network and you wish IPSec hosts to be allowed to access the Internet, appropriate Masquerading or NAT rules must be in place for the IPSec Pool.

L2TP over IPSec Client Parameters

This window allows you to define DNS and WINS servers which should be assigned to hosts when the connection is established.

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4.7.6.

CA Management

A Certificate Authority (CA) certifies the authenticity of public keys.

This ensures that the certificate used in a VPN connection really belongs to the endpoint, and not to an attacker. The CA Manage-

ment menu allows you to create and manage your own X.509

Certificate Authority (CA). The authority will verify the validity of

X.509 certificates exchanged during IPSec VPN connections. The relevant information is stored in the X.509 certficates.

But you can also use certificates, signed by commercial providers, such as VeriSign.

Note:

Every certificate has unique CA with respect to its identifying information (Name, Firm, Location, etc.). If the first certificate is lost, a second cannot be generated to replace it.

The CA Management menu allows you to manage three distinct kinds of certificates, which are used for different purposes. The three certificates differentiate themselves according to use, and, importantly, whether or not the Private Key is stored:

CA (Certificate Authority) Certificate: If a CA is saved without

private key, it can be used for the authentication of the host and user certificate of incoming IPSec connections: this type of CA is called a Verification CA.

If a CA saves its private key, it can be used to sign certificate queries, in order to produce a valid certificate. This CA is called a

Signing CA.

The system can contain a number of Verification CAs, but only one

Signing CA.

Host CSR (Certificate Signing Request): This is a request to have a certain certificate signed. When it is given to a Signing CA - and the CA verifies the identity of the owner – the CA sends back a fullyformed and signed Host Certificate.

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Host Certificate: This certificate contains the public key of the host as well as identifying information about the host (such as IP address or owner). The certificate is also signed by a CA, verifying that the

key does indeed belong to the entity named in the identification information. These valid certificates are used to authenticate remote

IPSec hosts/user endpoints.

The drop-down menu at the bottom of the table allows you to download certificates in various formats, or to delete certificates from the system:

PEM: A format encoding the certificate in ASCII code. The certificate, request, and private key are stored in separate files.

DER: A binary format for encoding certificates. The certificate, request, and private key are stored in separate files.

PKCS#12: A “container file”. One file can contain the certificate, private key, and verification CA.

Delete: Delete the specified certificate.

Issue CERT from CSR: This function signs a CSR, generating a full host certificate.

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Generating a Client/Host Certificate:

Step 1: Create a Signing CA.

1Under the IPSec VPN tab, open the CA Management menu.

2In the Certificate Authorities table, click the New button.

The Add Certificate Authority window will open.

304.

Select the Generate option.

305.

In the Name field, enter a descriptive Name for the certificate authority.


306.

Enter a password with at least four characters in the Pass-

phrase field.

307.

Use the Key Size drop-down menu to select the desired key length.

308.

Use the drop-down menus and entry fields from Country to

E-Mail Address to enter identifying on the CA.

309.

To save the entries, click the on the Start button.

The Signing CA will be loaded into the Certificate Authorities menu. This CA will answer CSR requests by generating new host certificates.

Step 2: Generate a Certificate Request.

1In the Host CSR or Certificate table, click the New button.

The Host CSR or Certificate window will open.

310.

Select the Generate CSR option.

In the VPN ID drop-down menu, select the type of VPN ID to use. If you select E-Mail Address, Hostname or IPv4 Ad-

dress, you must enter the relevant information in the field at right.

The field should be empty if you select the X509 DN option.

311


311.

In the Name field, enter a descriptive name for this certificate request.


312.

Enter a password with at least four characters in the

Passphrase field.

313.

Use the Key Size drop-down menu to select the desired key length.

314.

Use the drop-down menus and entry fields from Country to

E-Mail Address to enter identifying information about the

certificate holder.

Common Name: If the CSR is for a road warrior connection, enter the name of the user here. If the CSR is for a host, enter the hostname.

315.

To save the entries, click the on the Start button.

The Certificate Request CSR + KEY will appear in the Host CSRs and

Certificates table. The table will also show the type, name, and VPN

IP of the CSR. The request can now be signed by the Signing CA created in the first step.

Step 3: Generate the Certificate.

1In the Host CSRs and Certificates table, select the CSR + KEY certificate request.

2Use the drop-down menu at the bottom of the table to select the

Issue CERT from CSR function.

An entry field labeled Signing CA Passphrase will appear. Enter the password of the Signing CA here.

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Click Start.

From the CSR + KEY, the CA will generate the CERT + KEY certificate: the certificate will replace the CSR in the table.

Step 4: Download the Certificate.

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1In the Host CSRs and Certificates, select the new certificate.

2Use the drop-down menu at the bottom of the table to select a download format.

DER: In the Passphrase field, you must enter the password of the Private Key.

PEM: No password is necessary.

PKCS#12: Enter the password of the Private Key in the

Passphrase field. In the Export Pass field, enter a different password. This password will be required to install the certificate on the client computer.

317.

Click Start.

You must now install the certificate on the remote computer. The installation process depends on the IPSec software on that computer.

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4.7.7.

Advanced

This menu allows you, to make additional settings for the IPSec VPN option.

This should, however, only be done by experienced users.

NAT Traversal: When enabled, NAT Traversal allows hosts to establish an IPSec tunnel through NAT devices. This function attempts to detect if NAT firewalls are being used between the server and client: if so, the system will use UDP packets to communicate with the remote host. Please note that both IPSec nodes must support NAT traversal, and that road warrior nodes must be configured with a virtual IP address.

In addition, IPSec passthrough must be turned off on the NAT device

(s), as this can break NAT traversal.

Important Note:

You cannot use local IP addresses for the Virtual IP address, because the security system does not answer ARP requests for these.

Copy TOS Flag: Type-of-Service-Bits (TOS) are several four Bitflags in the IP-header. The Bits are referred to as Type-of-Service-

Bits, as they allow the transferring application, to tell the network which type of service quality is necessary. The available service quality classes are: minimum delay, maximum throughput, maximum reliability and minimum cost.

This function copies the content of the Type-of-Service field in the encrypted data packet, so that the IPSec data traffic can be routed according to its priority.

Enable the Copy TOS Flag function by clicking on the Enable button.

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Send ICMP Messages: If a data packet overwrites the configured

MTU value, the system will send an ICMP message to the source address: Destination unreachable/fragmentation needed.

This allows for using Path MTU Discovery.

Automatic CRL Fetching: There might be situations, in which the provider of a certificate attempts to revoke the confirmation awarded with still valid certificates, for example if it has become known that the receiver of the certificate fraudulently obtained it by using wrong data (name, etc.) or because an attacker has got hold of the private key, which is part of the certified public key. For this purpose, socalled Certificate Revocation Lists or CRLs are used. They normally contain the serial numbers of those certificates of a certifying instance, that have been held invalid and that are still valid according to their respective periods of validity.

After the expiration of this periods the certificate will no longer be valid and must therefore not be maintained in the block list.

The Automatic CRL Fetching function automatically requests the

CRL through the URL defined in the partner certificate via HTTP,

Anonymous FTP or LDAP Version 3. On request, the CRL can be downloaded, saved and updated, once the validity period has expired.

Enable the function by clicking on the Enable button (status light is green).

Please, check if the packet filter rules in the Packet Filter/Rules menu are configured such that the CRL Distribution Server can be accessed.

Strict CRL Policy: Any partner certificate without a corresponding

CRL will be rejected.

Enable the function by clicking on the Enable button (status light is green).

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Send ICMP Messages: If a data packet exceeds a set MTU value, the system will send the following ICMP message to the source address: Destination unreachable/fragmentation needed.

This allows for the use of Path MTU Discovery.

IKE debug Flags: This selection field allows you to configure the scope of IKE-debugging logs. The IKE Debugging function must be enabled in the IPSec VPN/Connections menu.

The following flags can be logged:

• State Control: control messages on the IKE status

• Encryption: encryption and decryption operations

• Outgoing IKE: content of outgoing IKE messages

• Incoming IKE: content of incoming IKE messages

• Raw Packets: message in unprocessed bytes

MTU: Enter a the MTU value in this entry field.

By default the MTU value is already defined: 1420 Byte.

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4.8. System Management (Reporting)

The Reporting function provides current information about the system, the state of various subsystems, and real-time information about various reporting functions. The displayed values are updated every five minutes.

The diagrams shown on the first page of the Reporting menus show an overview of the current day’s activity. By clicking the Show all … button you can open a page containing graphics built from weekly, monthly, and yearly statistics.

4.8.1.

Administration

The Administration menu contains an overview of the administrative events of the last 30 days. displayed:

• WebAdmin Logins

• Remote Logins

• Local Logins

• System Up2Dates

• Virus Pattern Up2Dates

• Intrusion Protection Pattern Up2Dates

• Config Changes

The following events will be

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• Configuration Manager Uploads

• System Restarts

• High Availability Takeover

4.8.2.

Virus

The following viruses will be displayed:

• SMTP viruses

• POP3 viruses

• HTTP viruses

The Virus menu contains an overview of the filtered viruses of the last 7 days.

4.8.3.

Hardware

This menu shows the current values relating to your system hardware. The system collects statistics about

CPU utilization, RAM utilization, and swap utilization.

The security system collects graphics and statistics every five minutes and updates them. The information can also be updated manually by clicking on the Reload button. Don’t use the Refresh button of the browser, because this will log you out of the WebAdmin configuration tool!

CPU Load (Daily Graph): This diagram shows the current utilization of the CPU.

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Memory Usage (Daily Graph): The current RAM utilization statistics are shown here. When more functions and subsystems are enabled on the firewall, more RAM will be required to support them.

SWAP Usage (Daily Graph): This diagram shows the current amount of swap space being used. Swap space is used to supplement

RAM: if your system is running out of available RAM, you will see a sharp increase in swap usage.

4.8.4.

Network

This menu shows current statistics relating to network traffic. These diagrams will not be useful unless the network cards have been correctly configured in the Network/

Interfaces menu.

The configuration process for network cards is described in chapter on page

122.

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4.8.5.

Packet Filter

Packet filter violations in diagrams will be displayed in a graphic in this menu.

The rule violations will also be logged to the Packet

Filter Logs. The log files are saved to the Local

Logs/ Browse menu.

4.8.6.

Content Filter

The processed data and actions of the Content Filter, relating to the

HTTP, SMTP and POP3 proxies will be displayed in the form of tables and diagrams in this menu. The Spam Protection option and the

Spam Score are described in chapter on page 265.

Information on the SMTP and POP3 proxies:

• Sum of the treated messages

• The average size of messages in kilobytes

• The average height of Spam Score

Information on the HTTP proxy:

• Sum of requested HTTP sites

• Sum of the HTTP sites, blocked by Surf Protection

• Sum of the HTTP sites, blocked by Virus Protection

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4.8.7.

PPTP/IPSec VPN

The PPTP and IPSec-VPN connections will be displayed in a graphic in this menu.

4.8.8.

Intrusion Protection

Intrusion Protection events will be displayed in a graphic in this menu.

4.8.9.

DNS

The DNS-Query-statistic is represented in this menu.

4.8.10.

HTTP Proxy Usage

The access to the HTTP-Proxy is recorded in this menu.

4.8.11.

Executive Report

In the Executive Report menu, a complete report is created from the individual reports in the Reporting tab.

Daily Executive Report by E-Mail

Once a day an updated complete report is sent to the e-mail addresses entered into the ordered list. The function is automatically enabled, once an address has been entered into the field.

New e-mail addresses are taken over to the ordered list by the entry field, by clicking on the Add button.

Ordered Lists are described in chapter on page 34.

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Current Report

Clicking on the Show button opens a window, in which the current complete report is displayed. This report can be printed out by clicking on the Print this

Report button.

4.8.12.

Accounting

The Accounting function monitors all IP packets, transmitted over the various network cards and, once a day, summarizes their size. Statistics for the preceding month are also generated at the beginning of each new month. These statistics are then used to generate a report. This report is useful, for instance, when an organization pays its service provider based on the volume of data transmitted.

Accounting is configured and enabled in the Network/Accounting menu. Further information is available in chapter on page 186.

Browse Accounting Reports: The existing accounting protocols will be displayed in this window. Select the month from the Select

Report drop-down menu. The report will appear in the window below.

Use the Local Logs/Browse menu to download or delete reports.

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Report for current Month: This window displays the accounting report for the current month.

Configuring Accounting:

1Under the Reporting tab, select the Accounting menu.

2Enable the Accounting Reports subsystem by clicking the Enable button.


318.

Use the selection field in the Queried networks window to select the networks for which detailed reports should be generated. This will usually include your LAN and/or DMZ networks.



Important Note:

Do NOT use the "Any" network, since it will match all source and destination networks, meaning no traffic will be counted in the report!

The changes will be applied immediately, and the networks will appear in the Queried networks window.

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4.8.13.

System Information

This menu offers additional system information. This information will be displayed in a separate window. Clicking on the Show button opens this window.

Disk Partition: This table lists the disk partitions on the system and their usage levels.

Process list: This tree lists all current processes on the

Internet security system.

Interface Information: All configured internal and external network cards are listed here.

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ARP Table: This table displays the current ARP cache of the system.

It lists all known associations between IP addresses and hardware

(MAC) addresses.

Local Network Connec-

tions: This table lists all current network connections to the firewall. Connections through the firewall are not shown.

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4.9. Remote Management (Remote Management)

The Remote Management tab contains the interfaces to further programs and tools, which allow you to remotely administer the security system and the private networks.

4.9.1.

Report Manager (RM)

The Report Manager collects and evaluates the log files generated on the security system.

Since data are compiled centrally on the Report

Manager, among others also the data from security solutions of other producers, the administrator can compare and analyze the messages because they are clearly laid out, and he can thus introduce the associated blocking measures against attacks fastly. The Report Manager is a distinct product that must be acquired separately.

In the RM menu, you enable the interface to the Report Manager

(RM) and make the settings for the generation of local log files: Next to the settings for the transfer of the RM Log Files to the Report

Manager you can also generate the RM Log Files for the historic log file archive and download them to a local computer.

This chapter describes the functions and settings contained in the RM menu. Depending on the existing network topology and the adjusted

Report Manager Network architecture, some settings must be made for the integration of the Remote Management Tool.

Possible Report Manager Network architectures are:

• Local RM Architecture

• Centralized RM Architecture

• Large-Scale RM Architecture

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The layout and the installation of those RM Network Architectures are described in the RM/NSMA5-Integration Guide.

The installation of the software and the required settings to connect the Report Manager to the Novell Security Manager

powered by Astaro security system are described in RM/

NSMA5-Integration Guide. The way to use the Report

Manager is described in the associated manuals. The guides and manuals are available at http://www.novell.com/

documentation/nsma51.

Report Manager (RM)

Status: Clicking on the Enable button enables the interface to the

Report Manager and the functions to generate RM Log Files (status light green).

Licensed IP Address: This entry field will be displayed once you have enabled the function in the Status line.

The scope of the license of the Report Manager depends on the amount of connected security systems. Those security systems are identified by means of your IP address. Enter the IP address of the network card through which the log files are sent to the RM Syslog

Server into the entry field. Once you have entered a valid IP address the RM Log Files are generated automatically during the Log File

Rotation process the next night. Those log files can then be downloaded manually to a local computer or sent automatically to a host via the functions of the other windows. Here, there are no Live

Logs for RM log files.

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Historical RM Log Files ates special Historical

Log Files, which can be imported and evaluated by the Report

Manager.

With this function the security system gener-

Generate Historical RM Logs: By clicking on the Start button all daily log files from the archive are comprised in one Historical-Log-

File.

The generation process is displayed in the ARM Log

File Merger window. This process is successful if only the arm-merge-all.pl: fin-

ished, exiting message is displayed in this window. If the process finished unsucnext to the message, such as not enough free space available, exiting, if there was not enough memory on the hard disk. cessfully, the reason for the interruption is displayed

Download Historical RM Logs: This function is available as soon as the first Historical-Log-File has been generated. Clicking on the Start button opens a dialogue by which the RM Log File (file:

arm_logs.tar) can be downloaded to a local computer.

RM Remote Connection

This window allows you to configure the RM Log Files Transfer. The new settings do not influence existing log files.

Status: Click the Enable button to enable the function (status light shows green).

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Security Note:

Both data transfer methods are unencrypted. If the log files are sent to a server outside the private network this should be done through a Host-to-Net IPSec VPN tunnel. An existing Net-to-Net connection can not be used!

Method: For the data transfer the methods Syslog and SMB/CIFS

Share are available. For both methods you must first define an RM server on the security system to which the RM Log Files are sent. The server and/or the host are added in the Definitions/Networks menu. Then you can make the following settings:

• The Syslog method is recommended for a LAN-network architecture. Once you have selected this method you make the following settings.

Host: From the drop-down menu select the RM server to which the RM Log Files shall be sent.

Service: Select the service from the drop-down menu that shall be used for the data transfer.

Do not confuse those settings with the tem/Remote

Sys-

Syslog menu:

There, usually only one Syslog Server can be defined for the security system. In the independent from that as Syslog-Server. The data are transferred in a special RM-compatible format so that the Report Manager works correctly.

• The SMB/CIFS Share method is recommended for a WANnetwork architecture. Once you have selected this method you make the following settings.

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Host: From the drop-down menu select the RM server to which the RM Log Files shall be sent.

Share Name: Enter the Windows Share Name in the entry field.

Ensure that the associated rights for the tab have been defined in the Report Manager.

Username: Enter the user name to use for the SMB Account.

Password: Enter the password for the SMB Account.


During a transfer with the SMB/CIFS

Share method the

RM Log Files are transferred as a

Gzip ASCII-file.

Those log files are in a tab that is subdivided according to year and month

(example: arm\2004\10\20041017.gz

).

The RM log files are generated once the interface to the Report

Manager is enabled and a valid IP-address has been entered in the

Licensed IP Address entry field. After the configuration of the RM

Remote Connection the RM log files are sent to the associated server.

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4.10.Local Logs (Log Files)

The logs, generated by the system will be managed in the Local Logs tab.

4.10.1.

Settings

Configure the basic settings for the creation of log files in the Settings menu.

Status: Click the Enable button to enable the function (status light shows green).

Important Note:

When this function is disabled, the Internet security system will not create Log Files!

Local Log File Archives: This function locally stores generated log files to the Security system. Configure the settings for the local log file archive in the Local Log File Archive window.

By default, this function is enabled automatically, once the logging functions are enabled.

Remote Log File Archives: This function allows you, to save the generated log files to a remote host or server. The settings for the automating of the log file archive on a separate server are configured in the Remote Log File Archive.

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Local Log File Archive

This window allows you to observe the utilization of the local log file partition.

The diagram first displays the used disk space in MB as well as the utilization of the partition in percent.

In the lower window, select from the drop-down menu, how the system has to react if a specific part of the partition is overloaded with log files. Three levels with different actions can be selected here.

Delete Log Files (span of time): In this drop-down menu select the length of time, in days, after which the log files will automatically be deleted by the security system.

Configuring the Log Files Level:

For each level, the following settings can be configured:

When Usage reaches: Configure here, at which utilization in percent of the system partition an action will be executed.

do this: Configure the action in this selection menu.

The following actions can be configured:

• Delete oldest Log Files: The oldest log files will automatically be deleted by the Security system. The administrator previously receives the WARN 711 notification e-mail.

• Send Notification: Only the INFO 710 notification e-mail with the correspondent warning will be sent to the administrator.

• Shut down System: The security system will automatically shutdown. The administrator receives the CRIT 712 notification e-mail before.

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• Nothing: No actions will be started.

Save the settings by clicking on the Save button.

Remote Log File Archive

In this window configure the settings for a remote log files archive. If the Remote

Log File Archive is on a server, you must first add it to the Definitions/Networks menu.

Configuring Remote Log File Archive:

1In the Global Settings window, enable the Remote Log File

Archives function by clicking on the Enable button.

The Remote Log File Archive window will open.

319.

Use the Type drop-down menu to select the archiving type.

The drop-down menus and/or entry fields for the selected archiving type will be displayed.

320.

Configure the settings for the archiving type.

3.1 FTP Server

Host: Use the drop-down menu to select a host.

Port: Use the drop-down menu to select a port.

By default, FTP is already selected.



Remote Path: Enter the path in the entry field.

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3.2 SMB (CIFS) Share




Share Name: Enter the share name in the entry field.

3.3 Secure Copy (SSH) Server

Public DSA Key: The Public DSA Key is displayed in this window.



Remote Path: Enter the absolute path in the entry field.

3.4 Send by E-Mail

E-Mail Address: Enter the e-mail address into this entry field.

321.


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4.10.2.

Local Log File Query

The Local Log File Query action allows you, to search for specific Log Files in a local archive. The search result will be displayed in a separate window.

Starting searches:

1In the Time Span drop-down menu select the time span.

2In the selection field Logs, choose the protocols.



322.

In the Mode drop-down menu, select the mode.

323.

If you are looking for protocols with specific strings, enter the strings into the Search Term entry field.

324.

Begin the search by clicking Start.

The protocols will be listed in a separate window.

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4.10.3.

Browse

Each protocol is contained in the Browse menu. If this menu is opened, the protocol groups (logs) will be displayed in the Browse

Local Log Files overview.

The Log File Overview

All protocol groups (logs) are contained in this overview. The groups with the current protocols can directly be opened from this overview.

The functions from the left to the right:

Selection box: This setting is required in connection with the dropdown menu at the footer of the table. Select the protocol groups and then choose the action (Delete or Download as ZIP File) from the drop-down menu.

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The action will start immediately.

Clicking on the selection box in the header selects all protocol groups.

( ): Clicking on the trash can icon deletes a group from the table.

Name: All protocols are listed in alphabetical order in this column.

Date: The date of current protocols will not be displayed.

( ): Clicking on the folder icon opens the sub-tab with all protocols of this group.

By clicking again on the icon, you will get back to the overview. The additional functions in the sub-tab are described in the „Log File Subtab“ section.

File Count/Name: The number of existing files will be displayed in this column. The old protocols can be opened from the sub-tab.

Activity: If the protocols in a group have been logged since Midnight, a correspondent message will be displayed:

• Now: The protocols are being generated right now.

• Today: Protocols have been generated since Midnight.

Open the current protocol (Live Log) by clicking on the message

Now or Today.

Size: The size of the log file group will be displayed in this column.

( ): Clicking the download icon will allow you to download this Log

File to your local client computer. You can then use these Log Files to import data into another program, for example Microsoft Excel.

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The Log File Sub-Tab

All protocols (Logs) of a group are listed in this sub-tab. The subgroup can be opened in the overview by clicking on the folder icon (

).

The following additional functions are available in the sub-tab:

Date: For older protocols, listed in the sub-tab the date and time will be displayed.

( ): Return to the overview by clicking on the folder icon.

( ): This is today's protocol. Clicking on the icon opens the Live

Log window.

( ): This in an archived protocol. Clicking on the symbol opens the

Log window.

File Count/Name: In the protocol from today, the path to the log file and the Live Log message will be displayed in this column.

In this column, the file names will be displayed next to the archived log files.

Filters

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The Filters function allows you to filter Log Files with specific attributes from the table. This function enhances the management of huge networks, as log files of a specific type can be presented in a concise form.

Filtering Log files:



325.

Enter the filter attributes in the fields. Not all attributes have to be defined.

Group: If you wish to filter the log files of a specific group, select it from the drop-down menu.

Month: This drop-down menu allows you to filter log files by a given month.

Type: This drop-down menu allows you to filter log files by a specific type.

326.

To start the filter click on the Apply Filters button.

Only the filtered log files will be displayed in the table. Next time when you open the menu, the complete log file table will be displayed.

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4.10.3.1.

Log Files

This chapter contains all available logs. These log files will only be displayed in the Browse menu, if the correspondent processes have been recorded by the System. The following Accounting data log file, for example, will only be displayed, once the Accounting function has been enabled in the Network/Accounting menu.

Accounting data: These log files contain all Accounting logs, archived by the system. The Reporting/Accounting menu allows you to view the current logs.

Configuration Manager: If the Internet security system is configured remotely via the Configuration Manager, the correspondent processes will be logged to these log files.

User Authentication daemon: The activities of the UA Daemon are logged to these log files. UA is used as the central authentication daemon for various services.

Boot messages: The boot messages are recorded to these log files.

Configuration daemon: The activities of the AUA Daemon are logged to these log files. The log files belong to the support logs and will only be displayed after clicking on the show support logs button.

Content Filter: The activities of the content filters on the HTTP,

SMTP and POP3 Proxies are logged to these log files.

DHCP client: If the interfaces are automatically assigned to IP addresses on the Internet security system, the activities are recorded to these log files.

DHCP server: If the Internet security system is used as DHCP-server and assigns dynamic IP addresses to the clients in the network, the activities are recorded to these log files.

Fallback archive: These log files are used as a security archive for logged processes, which cannot be assigned to one of the log files.

The log files belong to the support logs and will only be displayed

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Using the Security System after clicking on the show support logs button. In general, those log files are empty.

High Availability: The activities of the High-Availability-(HA) system are logged to these log files.

HTTP daemon: The log files for the HTTP daemon belong to the support logs and will only be displayed after clicking on the show

support logs button.

WebAdmin access: The requests to the user data base are recorded to these log files.

Intrusion Protection: The activities of the Intrusion Protection

System (IPS) are recorded to these log files.

IPSec VPN: Extensive information on the configuration of the IPSec-

VPN and L2TP-over-IPSec-connections is recorded to these log files. And also information on the Key Exchange and Encryption.

Virus Protection: The activities of the Virus Protection System are recorded to these log files.

Kernel: The Kernel logs record the system status, including messages from device drivers, messages relating to the boot process, and information about blocked packets.

Logging: The local archives of the log files on the Internet security system and the forwarding of files to the Remote-Log-File-Archive are recorded to these log files.

Local login: Information on the log-in processes to the local console is recorded to these log files.

MiddleWare: The activities of the MiddleWare are recorded to these log files. The log files belong to the support logs and will only be displayed after clicking on the show support logs button.

Network accounting daemon: The efficiency of the accounting is recorded to these log files.

BIND name server: The releases of host names to IP addresses are recorded to these log files.

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Admin notifications: The Notification Log Files record all notification e-mails sent by the firewall. This allows an administrator to monitor critical system messages even if the e-mail system is down.

Error, warning, and information codes are listed in chapter on page

344.

HTTP proxy: The HTTP proxy logs show the activity of the HTTP proxy.

Packet Filter: Messages relating to blocked packets are shown in the

Packet Filter logs. These log files are also included in the kernel logs.

POP3 proxy: The activities of the POP3-Proxy are logged to these log files. All outgoing e-mails will be listed there. In addition, all irregularities, such as interruptions or blocked e-mails will be logged.

Portscan Detection: The Portscan Detection system watches for and blocks portscans and sends e-mail messages to the administrator.

When examining the Log Files, however, do not draw too many conclusions from the source IP addresses (SRC) and port numbers

(SPT), as they can easily be falsified by the sender. The destination addresses (DST) and port numbers (DPT), however, provide useful information about what the scanner was looking for.

PPPoA DSL dial-up: The processes executed in the dial-up with PPP

over ATM are recorded to these log files.

PPPoA DSL dial-up: The processes executed in the dial-up with PPP

over Ethernet are recorded to these log files.

PPTP VPN Access: These logs record the progress of PPTP sessions from external clients. This includes login and authentication information as well as error messages.

If you select the Extensive parameter in the Logging function of the

Network/PPTP VPN Access menu, these logs will contain very detailed information about PPP connections. integrity of the firewall systems and notifies the administrator of

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Using the Security System important events. Self-monitoring checks the function, performance and security of relevant system parameters and remedies deviations, exceeding given tolerances. Subsequently a report will be sent to the competent administrator by e-mail.

This Selfmonitoring of the security system ensures that central services such as the Syslog Daemon, HTTP Proxy, and Network

Accounting are functioning properly.

Access rights to files are monitored, as is the resource usage of individual processes. This is designed to prevent an overload of the system. Moreover, the system administrator is informed in time on previsible resource bottlenecks, if, for example the available disk space is running short. This allows for an early implementation of measures in favor of a system extension and/or discharge.

SMTP proxy: The activities of the SMTP-proxy are recorded to these log files. All ingoing e-mails will be listed there. In addition, all irregularities, such as assigned Bounce conditions, interruptions or blocked e-mails will be logged.

SOCKS proxy: The activities of the SOCKS-proxy are recorded to these log files.

SSH remote login: Information on the log-in processes to the remote shell is recorded to these log files.

System log messages: These Log Files record generic information about the daemon processes running on the system. Among other things, the access to the SNMP-service and the activities of the

Dynamic DNS function, are recorded to these log files.

Up2Date Service messages: The activities of the Up2Date Service are recorded to these log files. This comprises also the System

Up2Date and Pattern Up2Date processes.

Uplink Failover messages: The activities of the configured failovers are recorded to these log files.

WebAdmin usage: The use of the WebAdmin configuration tool is recorded to these log files. The logs contain the configuration

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111

112

150

151

152

153

105

106

107

108

109

110 changes, implemented by the configuration tool and also the log-in and log-out processes.

4.10.3.2.

Error Codes

The following is a list of all error, warning, and information codes with their meanings:

INFO:

000 System was restarted

System was restarted

A system backup file was generated automatically and sent via e-mail to the Administrator.

User Authentication deamon (UA) not running – restarted

Cron Task Scheduler not running – restarted

WebAdmin webserver not running – restarted ssh server not running – restarted license server not running – restarted configuration database server not running – restarted syslog server not running – restarted middleware not running – restarted

Root partition mounted at / is filling up please check tmpfs partition mounted at /opt/tmpfs is filling up - please check secure application partition mounted at /var/sec is filling up - please check logfile partition mounted at /var/log is filling up - please check

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154

155

300

302

303

320

321

Using the Security System storage application partition mounted at / var/storage is filling up - please check

Up2Date partition mounted at /var/up2date is filling up - please check

System Up2Date: System Up2Date started

Further information on the Up2Date Service can be found in chapters on page 48.

System Up2Date: No new System Up2Date packages available

System Up2Date succeeded: Prefetched new System

Up2Date package(s)

For more Up2Date package information please see attachted Up2Date description file.

Further information on the System Up2Date can be found in chapters on page 48.

System Up2Date failed: License is not valid

System Up2Date: Started System Up2Date installlation in HA-Master-Mode

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351

352

353

354

322

323

350

360

361

700

System Up2Date: New System Up2Dates installed

Further information on the Up2Date package(s) can be found in the notification e-mail.

System Up2Date: Started System Up2Date Installation

Pattern Up2Date: Started Pattern Up2Date

Further information on the Up2Date Service can be found in chapters on page 48.

Pattern Up2Date: No new pattern available for

Virus Protection

Pattern Up2Date: No new pattern available for

Intrusion Protection

Pattern Up2Date: Trying another pattern type

Pattern Up2Date succeeded: Updated new Intrusion

Protection patterns

For more information please see the notification e-mail. Further information on the System Up2-

Date can be found in chapters on page 48.

Virus Pattern Up2Date: No pattern installation for Virus pattern needed

Virus Pattern Up2Date succeeded: Installed new

Virus Pattern

For more information please see the notification e-mail.

Daily log file archive

This is an archive file containing the log files. The date of these log files is specified in the notification.

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710

850

851


Log file partition is filling up

The log file partition usage reached the specified value in percent. Depending on your configuration the system will automatically take measures if the usage continues to grow. To make sure you don't lose any important log files, please check the WebAdmin settings and/or remove old log files manually.

Intrusion Protection Event

A packet was identified that may be part of an intrusion. The matching rule classified this as low priority level. Further information on the

Intrusion Prevention event can be found in the notification e-mail.

Intrusion Protection Event – Event buffering activated

A packet was identified that may be part of an intrusion. The matching rule classified this as low priority level. Event buffering has been activated. Further Intrusion Protection events will be collected and sent to you when the collection period has expired. If more events occur, this period will be increased. Further information on the Intrusion Prevention event can be found in the notification e-mail.

A portscan was detected. The originating host was: <IP>

A portscan from the given IP address was detected. The Portscan Detection function is described in chapter , on page 190.

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856

For more information:

- see WebAdmin -> Local Logs/Browse/Portscan

- search with whois to know who the source

IP belongs to:

-> RIPE NCC http://www.ripe.net/perl/whois?

query=$HOST

-> ARIN - http://www.arin.net/cgi-bin/whois.pl?

queryinput =$HOST

-> APNIC - http://cgi.apnic.net/apnic-bin/

whois.pl?search=$HOST

- use traceroute from

-> UC Berkeley

- http://www.net.berkeley.edu/cgi-bin/

traceroute? $HOST

Attention: source IP addresses can easily be forged by attackers.

Portscan detected - Event buffering activated

A portscan was detected. The originating host was: <IP>

A portscan from the given IP address was detected. The Portscan Detection function is described in chapter , on page 190.

Event buffering has been activated. Further

Intrusion Protection events will be collected and sent to you when the collection period has expired. If more events occur, this period will be increased. Further information on the Intrusion Prevention event can be found in the notification e-mail.

File transfer request 999

348


This is the file you requested.

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WARN:

001

005

080

081

A feature will expire! The feature ... is time limited and will expire in ...

Please contact your local Novell partner or a

Novell sales representative to obtain a license update. E-Mail addresses:

America's: www.novell.com/offices/americas,

Europe, Asia Pacific and Africa: www.novell.com/offices.

For technical questions, please feel free to visit our user bulletin board at http://support.novell.com/forums/2sm.html, or our documentation resources at http://www.novell.com/documentation/nsma5.

Failed login attempt from ...(IP) at ...(time) with ...( username)

HA check: no link beat on interface – retrying

The link beat monitoring system on the firewall failed. The system will now try again. If the system continues to fail, the administrator will receive message WAR 081.

If you do not wish to use this monitoring function, no further action is required. After the system sends the WAR 081 message, it will not try to start the link beat monitoring system again.

HA check: interface does not support link beat check

The link beat monitoring system failed after multiple attempts. If you have recently installed the HA system, and you intend to use the

350

158

159

711

715

Using the Security System link beat monitoring system, please check that the network cards support link beat, and that they are supported by the security system. Also check to make sure that the link beat capable cards have been chosen for the data transfer connection.

The installation and management of the HA system is described in chapter , on page 98.

Interface uplink usage exceeds configured limit

On a Standard-Ethernet-interface the function

„Monitor Interface Usage“ was activated. The maximum value for the Uplink-Bandwidth was exceeded.

Interface uplink usage exceeds configured limit

On a Standard-Ethernet-interface the function

„Monitor Interface Usage“ was activated. The maximum value for the Downlink-Bandwidth was exceeded.

Log file(s) have been deleted

The log file partition usage reached the specified value in percent. Log Files have been deleted. To make sure you don't lose more log file(s), please check the WebAdmin settings and/or remove old log files manually. The deleted files and/or directories are listed in the attachment.

Remote log file storage failed

The daily log file archive could not be stored on the configured remote server. Please check the WebAdmin settings for:

Local Logs/Settings/Remote log file archive

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850

851

CRIT:

301

302

The archive file will be automatically retransfered with the next daily log file archive.


A packet was identified that may be part of an intrusion. The matching rule classified this as medium priority level. Further information on the Intrusion Prevention event can be found in the notification e-mail.


A packet was identified that may be part of an intrusion. The matching rule classified this as medium priority level. Event buffering has been activated. Further Intrusion Protection events will be collected and sent to you when the collection period has expired. If more events occur, this period will be increased. Further information on the Intrusion Prevention event can be found in the notification e-mail.

System Up2Date failed: Could not connect to

Authentication Server(s)

The authentication server is not reachable. If the problem continues, please contact the support department of your firewall provider.

System Up2Date failed: Download of System

Up2Date Packages failed

If the problem continues, please contact the support department of your firewall provider.

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305

306

320

322

323

324

325


System Up2Date: Wrong MD5sum for local System

Up2Date package

Please download a new Up2Date package. If the problem recurs, please contact the support department of your firewall provider.

System Up2Date failed: Wrong MD5sum for downloaded Up2Date Package

Please download a new Up2Date package. If the problem recurs, please contact the support department of your firewall provider.

System Up2Date failed: Wrong start parameters

If the problem recurs, please contact the support department of your firewall provider.

System Up2date stopped: Next Up2Date installlation locked by HA

System Up2Date failed: Corrupt Up2Date Package

Found corrupt Up2Date package. Please start process again. If the problem recurs, please contact the support department of your firewall provider.

System Up2Date failed: Invalid License

Your license is no longer valid.

System Up2Date failed: License check failed

Your license could not be checked. If the problem continues, please contact the support department of your firewall provider.

333 System Up2Date failed: Internal error

The system update failed. Please contact the support department of your firewall provider.

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341

342

343

354

334

335

336

337

338

339

340

System Up2Date failed: Invalid syntax


System Up2Date failed: Could not read Up2Date directory


System Up2Date failed: No installation directory


System Up2Date failed: Could not extract tar

Please start process again. If the problem recurs, please contact the support department of your firewall provider.

System Up2Date failed: Main Up2Date package not found

Please start process again. If the problem recurs, please contact the support department of your firewall provider.

System Up2Date failed: Version conflict


System Up2Date failed: Pre-Stop-Services script failed

System Up2Date failed: Post-Stop-Services script failed

System Up2Date failed: Pre-Start-Services script failed

System Up2Date failed: Starting Services failed

344

345

346

347

351

352

353

354



System Up2Date failed: Post-Start-Services script failed

System Up2Date failed: Error occured while running installer


System Up2Date failed: Installer ended due to internal error


System Up2Date failed: Started without rpm parameters


Pattern Up2Date failed: Could not select



Pattern Up2Date failed: Could not connect to


The authentication server is not reachable. If the problem continues, please contact the support department of your firewall provider.

Virus Pattern Up2Date failed: Could not connect to Up2Date Server

The Up2Date server is not reachable. If the problem continues, please contact the support department of your firewall provider.

Intrusion Protection Pattern Up2Date failed:

Could not connect to Up2Date Server

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355

356

357

358

360

361

362

The Up2Date server is not reachable. If the problem continues, please contact the support department of your firewall provider.

Virus Pattern Up2Date failed: No active bases for Virus Patterns found

Intrusion Protection Pattern Up2Date failed: No active bases for Intrusion Protection Patterns found

Virus Pattern Up2Date failed: Internal MD5Sum

Error

Could not create correct MD5Sums. If the problem recurs, please contact the support department of your firewall provider.

Intrusion Protection Pattern Up2Date failed:

Internal MD5Sum Error

Could not create correct MD5Sums. If the problem recurs, please contact the support department of your firewall provider.

Pattern Up2Date failed: Licence Check failed

Your license could not be checked. If the problem continues, please contact the support department of your firewall provider.

Pattern Up2Date failed: Restart of Virus Scanner failed


Pattern Up2Date failed: MD5Sum Error occurred


System shut down due to full log file partition 712

356

850

851

860


The log file partition usage reached the specified value in percent. To prevent the loss of important log files, the system has been shut down automatically. Please check the WebAdmin settings and/or remove old log files.


A packet was identified that may be part of an intrusion. The matching rule classified this as highest priority level. Further information on the Intrusion Prevention event can be found in the notification e-mail.


A packet was identified that may be part of an intrusion. The matching rule classified this as highest priority level. Event buffering has been activated. Further Intrusion Protection events will be collected and sent to you when the collection period has expired. If more events occur, this period will be increased. Further information on the Intrusion Prevention event can be found in the notification e-mail.

Intrusion Protection Event - Buffered Events

After the activation of the event buffering further IPS events have been collected. Please see the attached file for a list of collected events. This list will show you a maximum of events. A complete event history has been stored in the Intrusion Protection log files.

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4.11.Online Help

The Help menu contains further functions for use with the Online

Help system.

Search

This function allows you to search WebAdmin’s Online Help system for a particular term. Results will appear in a separate window.

Starting a search:

1Under the Online Help tab, open the Search menu.

2Enter your search term in the Search term field.

3Begin the search by clicking Start.

If the term is found in either WebAdmin or the Online Help system, the following results will be returned:

• path to the relevant function in WebAdmin

• link to the relevant Online Help page

• Information on the function or texts of the Online help with the expression, searched for

Glossary

The glossary explains the concepts and terms used in WebAdmin.

Click a term to see a short explanation.

358


4.12.Exiting the Security System

If you close a browser running a WebAdmin session without using the Exit function, the session will remain active until the timeout is reached. .................................

In such a case you can again log in to WebAdmin. A screen will be displayed, informing you that already another user is logged in. To log in again, first end the other session by clicking the Kick button. If you wish to end another administrator’s active session, you can type a message in the “Type reason here” field which will be transmitted to the other administrator.

359

Glossary

Glossary

Broadcast

The address used by a computer to send a message to all other computers on the network at the same time.

Example: A network with IP address 192.168.2.0 and network mask

255.255.255.0 would have a broadcast address of 192.168.2.255.

Client

A client is a program that communicates over a network with a server in order to make use of a particular service.

Example: Netscape is a WWW client, and communicates with a WWW server to download web pages.

Client-Server model

Applications based on the client-server model use a client program on the user’s computer to communicate with a central server program on the network. The server is usually responsible for keeping track of the data, while the client is responsible for presenting the data to the user. In order to function correctly, the client and server must both use a well-defined network protocol to communicate. All important applications on the Internet (e.g., WWW, FTP, news) use this model.

DNS

The Domain Name Systems (also: The Domain Name Service) translates the underlying IP addresses of Internet-connected computers into more human-friendly names or aliases and vice-versa.

This translation from number to name is done by the name server.

Every Internet-connected institution must employ at least two separate DNS servers to answer queries about its internal DNS names and IP numbers. Every top-level domain also has name servers which contain information about their subordinate servers.

360

Glossary

The DNS system is thus a distributed, hierarchical database. DNS resolution is normally handled by network applications rather than by the user him or herself.

Dual-Homed Gateway

A dual-homed gateway is a computer that is directly connected to two networks (i.e., it has two network cards, each connected to a different network) and which forwards information from one network to the other. Due to the fact that there is no IP forwarding, all connections must be forwarded through this Dual-Homed Gateway.

Firewall

A firewall protects one network or subnet (e.g., an internal LAN) from another network (e.g., the public Internet). All traffic between the two passes through the firewall, where it is controlled and monitored.

Header

In general, the header is the information contained at the top of a file or message, and consists of low-level data regarding the status and handling of the file or message. In particular, the header of an e-mail or Usenet message contains information such as the sender, recipient, and date.

Host

In a client-server architecture, the host is the computer which runs the server software. One host can have multiple server programs running on it: that is, an FTP server, mail server, and web server can all run on the same host. A user uses a client program, for instance a browser, to access the server on the host. The word Server is also often used to refer to the computer on which the server software runs, diluting the distinction between server and host in practice.

In telecommunications, the host is the computer from which information (such as FTP files, news, or WWW pages) is retrieved. On the Internet, hosts are often also called nodes.

361

Glossary

Using an Internet host (as opposed to a Localhost), for example with

Telnet, one can work from a distance (Remote Access).

ICMP

Next to the IP Protocol, there is an option with specific functions.

The Internet Control Message Protocol (ICMP) is a special kind of

IP protocol used to send and receive information about the network’s status and other control information. Many users are already familiar with ICMP echo requests (type 8) and echo replies

(type 0), as these are used by the ping program. When a computer receives an echo request, its IP stack sends back an echo reply: This is done with the ping program in order to determine, whether another network component is reachable.

IP

The Internet Protocol is the basic protocol of the Internet, and has been used without change since it was first developed in 1974. It handles the basic transmission of data from one computer to another, and serves as the basis for higher-level protocols like TCP and UDP. It handles the connection and error management. Technologies like

NAT and Masquerading allow large private networks to hide behind small numbers of IP addresses (or even single addresses), thus allowing the relatively limited IPv4 address space to meet the demands of an ever-expanding Internet.

362

Glossary

IP Address

Every (publicly-addressable) host on the Internet has a unique IP address, similar to a telephone number. An IP address consists of decimal numbers, separated by points. Possible numbers are 0 to 255 inclusive. ................................

Example: a possible IP address is 192.168.2.15.

At least one IP name in the form hostname[[.subdomain]s].domain

, e.g. kises.rz.uni-konstanz.de is assigned to an IP address. This refers to a computer, named kises

, which stands in the sub-domain rz

of the sub-domain uni-konstanz

of the de

domain. As with IP addresses, the individual parts of the name are separated from each other by a point. Whereas, in contrast to IP addresses, IP names are not limited to four numbers. Moreover, several IP names can be assigned to one IP address, which are referred to as aliases.

Masquerading

Dynamic Masquerading is a technology based on NAT that allows an entire LAN to use one public IP address to communicate with the rest of the Internet.

Example: The administrator has established an internal LAN, and has given each computer on it IP addresses from the private IP range.

One computer, for example, has the address 192.168.2.15. Only one, official IP address (e.g., 199.199.199.1) is assigned to all computers in its network, i.e. if only one HTTP request starts to the Internet, its

IP address will be replaced by the IP address of the external network card. The data traffic for the external network (Internet) thus does not contain internal information. The answer to the request will be recognized by the firewall and forwarded to the requesting computer.

363

Glossary nslookup

Nslookup is originally a UNIX program designed to query name servers. The main application is the display of IP names in the case of a given IP number and vice versa. Moreover also additional functions, such as aliases can be displayed.

Port

While at the IP level, only sender and destination addresses are important, the TCP and UDP protocols both include the concept of ports. A port is an additional identifier – in the cases of TCP and UDP, a number between 0 and 65535 – that allows a computer to distinguish between multiple concurrent connections between the same two computers. TCP and UDP packets have both a sending port and a destination port.

Protocol

A protocol is a well-defined and standardized set of rules that govern how a client and server interact. Some well-known protocols and their associated services include HTTP (WWW), FTP (FTP), and NNTP

(news).

Proxy (Application Gateway)

Proxies, often called application gateways, separate two networks at the network (IP or TCP/UDP) level, while still allowing certain kinds of communication. There can be no direct connection between an internal system and an external computer.

Proxies exclusively operation the application level. Proxies-based firewalls use a Dual-Homed Gateway that does not forward IP packets. Proxies, operated as specialized programs on the gateway, can now receive connections for a specific protocol, treat the transmitted traffic on the application level and forward it afterwards.

364

Glossary

RADIUS

RADIUS stands for Remote Authentication Dial In User Service. It is a protocol designed to allow network devices such as routers to authenticate users against a central database.

Router (Gateway)

A router is a network device that is designed to forward packets to their destination along the most efficient path. Strictly speaking, a gateway is not always a router (it could be an application gateway, or proxy) – though a router is a kind of circuit-level gateway. When a computer wants to communicate with a server not on the local network, it must pass the data to a router in order for the packets to be forwarded to their destination: By convention, the highest or lowest address in the network range is used for the router: for example, in the network 192.168.179.0/24, the router will normally be at either 192.168.179.254 or 192.168.179.1.

Server

A server is a network-connected computer that offers services to client computers. Standard services include WWW, FTP, news, and so on. In order to make use of these services, the user will need a client program (e.g., Netscape) to communicate with the server.

SOCKS

SOCKS is a proxy protocol that allows a point-to-point connection between an internal and an external computer. SOCKS, often called the Firewall Traversal Protocol, is currently at version 5 and must be implemented in the client-side program in order to function correctly.

365

Glossary

Subnet Mask

The subnet mask (also called netmask) of a network, together with the network address, defines which addresses are part of the local network and which are not. Individual computers will be assigned to a network on the basis of the definition.

UNC-Path

The Universal Naming Convention path is used primarily by computers running a Microsoft operating system to uniquely designate network resources. UNC paths are usually of the form

\\Server\Resource.

366

Index

Accounting

adding/deleting a network card

introduction

Acoustic signals

beep, 5 times

administrator e-mail addresses

Backup

editing e-mail addresses

encryption of e-mail backup file

generating e-mail backup file

introduction

load

manual creation

Broadcast

Internet-wide

segment-wide

Browser MS Explorer

disabling proxy use

Browser Netscape

disabling proxy use

Connection Tracking Helpers

introduction

loading helper modules

Connection Tracking Table

Current System NAT Rules

Current System Packet Filter Rules

DHCP Server

assigning DNS servers, Gateway IP and WINS server

configuring

current IP leasing table

introduction

DNS

configuring

Dynamic DNS

defining Host

Glossary

221

214

215

219

219

219

209

210

222

62

60

61

55

56

58

187

186

105

39

177

176

179

176

242

122

367

Glossary

introduction

Error codes

CRIT

INFO

WARN

Errors

causes

Exit

Factory Reset

Firewall Hostname

General System Settings

Glossary

broadcast

client

client-server model

DNS

dual-homed gateway

firewall

header

host

ICMP

IP

IP address

masquerading

nslookup

port

protocol

proxy

RADIUS

router

server

SOCKS

subnet mask

UNC path

Glossary

Header

High Availability

introduction

High Availability-System

368

362

363

363

364

364

364

364

365

365

365

365

366

366

358

360

360

360

360

361

361

361

361

362

268

98

121

352

344

350

20, 126

359

44

121

39

installing

Hostname

HTTP

ActiveDirectory/NT Domain Membership mode

advanced

defining Parent proxy

enabling the proxy

global settings

operation modes

Parent Proxy

standard mode

transparent mode

user authentication mode

ICMP

firewall forwards ping

firewall forwards traceroute

firewall is ping visible

firewall is traceroute visible

ICMP forwarding

ICMP on firewall

introduction

log ICMP redirects

ping on firewall

ping settings

traceroute from firewall

traceroute settings

Ident

forward connections

introduction

Installation

configuration

instructions

preparation

software

Installed Licenses

Interfaces

adding additional addresses

additional address on Ethernet interface

configuring a virtual LAN

configuring PPPoA-DSL

configuring PPPoE-DSL

Glossary

100

121

214

213

214

213

211

212

211

212

214

214

213

212

224

227

226

224

223

223

226

223

223

223

250

250

21

16

16

16

46

133

133

147

156

150

369

Glossary

current interface status

downlink bandwidth (kbits)

Ethernet network card

hardware list

introduction

monitor interface usage

MTU size

notify when downlink usage below (%)

notify when downlink usage exceeds (%)

notify when uplink usage below (%)

notify when uplink usage exceeds (%)

PPP over Serial Modem Line

PPPoE-DSL connection

PPPoE-DSL connections

proxy ARP

QoS status

setting up PPP over serial modem

standard Ethernet interface

uplink bandwidth (kbits)

uplink failover on interface

Uplink Failover on Interface

virtual LAN

wireless LAN

wireless LAN access point

wireless LAN security


124

131, 148, 153, 159, 164

127

125

122

130

131, 148, 153, 159, 164

131

131

131

131

160

150

155

128

130, 148, 152, 158, 163

160

127

130, 148, 153, 159, 163

128

162

145

135

139

136

advanced

global settings

introduction

IPS rules overview

notification levels

portscan detection

rules

setting rule

IPSec VPN

197

190

190

193

192

190

192

195

advanced

AH protocol

CA management

connections

global IPSec settings

introduction

IPSec

370

314

286

309

288

289

280

284

IPSec connections

IPSec modes

IPSec protocols

IPSec system information

key management

L2TP over IPSec

local IPSec X.509 key

local keys

manual key distribution

Policies

PSK authentication

remote keys

RSA authentication

transport mode

tunnel mode

VPN Routes

VPN status

L2TP over IPSec

L2TP over IPSec client parameters

L2TP over IPSec IP pool

L2TP over IPSec settings

Licensed Users

Licensing

Load Balancing

deleting rules

editing rules

introduction

Local Logs

browse

configuring local log file level

configuring remote log file archive

delete log files (after span of time)

filtering

filters

introduction

local log file archive

local log file query

log files

remote log file archive

settings

starting search

Glossary

175

175

173

336

332

333

332

339

338

331

332

335

340

333

331

335

371

308

308

307

46

44

290

284

286

290

287

307

301

301

287

297

303

304

302

285

285

290

290

Glossary

Log files

error codes

Log Files

Admin notifications

BIND name server

boot messages

configuration daemon

Configuration Manager

content filter

DHCP client

DHCP server

fallback archive

High Availability

HTTP daemon

HTTP proxy


IPSec VPN

kernel

local login

logging

MiddleWare

network accounting deamon

packet filter

POP3 proxy

portscan detection

PPPoE DSL dial-up

PPTP VPN access

selfmonitoring

SMTP proxy

SOCKS proxy

SSH remote login

system log messages

Up2Date Service messages

uplink failover messages

user authentication daemon

Virus Protection

WebAdmin access

WebAdmin usage

Log FTP Data Connections

Log Unique DNS Requests

Logging Options

372

344

341

342

342

342

342

342

341

341

341

341

341

341

342

341

340

340

340

340

340

340

340

341

341

342

342

343

343

343

343

343

343

340

341

341

343

217

217

217

Masquerading

deleting rules

editing rules

introduction

NAT

defining rules

deleting rules

editing rules

introduction

Networks

adding DNS server

adding host

adding network

defining IPSec user group

defining network group

deleting definitions

editing definitions

filtering

filters

introduction

Notification

Packet Filter

advanced

system information

Packet Filter Live Log

introduction

Setting/Resetting filters

Packet filter rule

sorting rules table

Packet Filter Rules

adding/editing groups

deleting rules

editing rules

enable, disable rules

filtering

filters

introduction

re-ordering rules

rules table

Pattern Up2Date

Glossary

173

173

172

170

172

172

168

109

107

108

110

109

112

112

111

111

106

121

214

218

218

219

205

205

205

205

205

206

206

199

205

204

373

Glossary

installation, automatic

installation, manual

Phishing Mail

Ping Check

introduction

POP3

configuring

Content Filter

header

Spam Protection

Virus Protection

PPTP VPN

introduction

MS Windows 2000 Scenario

PPTP client parameters

PPTP IP-pool

PPTP VPN access

Protocol Handling

Protocols

AH

ESP

IP

TCP

UDP

Proxy

DNS

HTTP

Ident

introduction

POP3

Proxy Content Manager

SMTP

SOCKS

Proxy Content Manager

age

automatic cleanup

daily spam digest

deferred

filtering

filters

374

54

53

275

188

245

246

248

246

246

180

182

182

181

180

216

113, 115

113, 115

115

113

113

241

221

250

220

245

274

251

243

274

278

279

275

277

277

global actions

mail-ID

permanent error

quarantined

recipient(s)

sender

smtp_queue

Quality of Service (QoS)

Remote Management

introductions

RM

Remote Syslog Server

introduction

Reporting

accounting

administration

content filter

current report

daily executive report by e-mail

DNS

executive report

hardware

HTTP proxy usage


network

packet filter

PPTP/IPSec VPN

system information

virus

Restart

RM

historical RM log files

Report Manager (RM)

RM remote connection

transfer method

Routing

introduction

kernel routing table

Search

starting a search

Glossary

326

326

64

322

317

320

322

321

321

321

318

321

321

319

320

321

324

318

105

277

274

275

275

276

275

275

207

328

327

328

329

166

167

358

375

Glossary

Search

Secure Shell

Services

adding

defining service group


editing definitions

filtering

filters

introduction

Settings

Shut down

Shut down/Restart

SMTP

advanced settings

configure

content filter

deny RCPT hacks

domain adding and editing

domain groups

domain-groups table

DoS protection

editing domain profile

expression filter

feature settings

file extension filter

MIME error checking

outgoing TLS

profiles and domain group assignment table

route target

scan outgoing messages

sender blacklist

SMTP authentication

Spam Protection

SPF fail check

use BATV

use greylisting

use RBL

use smarthost

verify recipient

376

358

43, 44

114

115

117

117

116

116

113

39

105

105

271

265

256

256

257

256

273

258

259

262

261

273

254

254

260

255

272

252

260

256

254

254

252

272

258

264

verify sender

virus protection

Virus Protection

SNMP

assigning the trap server

authorizing access

introduction

SOCKS

configuring

Static Routing

defining routes

introduction

Strict TCP Session Handling

Surf Protection

assigning profiles

categories

content removal

editing categories

enabling, profiles adding

introduction

profile assignment table

profile functions

profiles editing

profiles table

skip image scanning

URL blacklist

URL whitelist

Whitelist Domains

SYN Rate Limiter

System Requirements

administration PC

example configuration

hardware

System Time

automatic synchronization

manual configuration

System Up2Date

installing

installing with HA solution

loading and installation, manual

Glossary

258

263

263

63

62

62

244

166

166

216

239

229, 233

234

230

234

229

237

232, 238

235

231

240

233

232

229

215

52

52

50

377

14

14

13

42

41

Glossary

loading, automatic

loading, local

Time Settings

Up2Date Service

defining upstream proxy server

introduction

Pattern Up2Date

System Up2Date

use upstream HTTP proxy

Use external indicators

User Authentication

Active Directory/NT Domain Membership

Active Directory/NT Membership configuration

configuring LDAP

configuring MS Active Directory server

configuring Novell eDirectory server

configuring OpenLDAP server

introduction

LDAP advanced

LDAP server

Microsoft IAS RADIUS configuration

NTLM

RADIUS

SAM

SAM – NT/2000/XP configuration

Users

adding local users


editing definitions

filtering

filters

introduction

Validate Packet-Length

WebAdmin

access and authentication

block password guessing

configuring blocking protection for Loggin attempts

drop-down menus

general settings

HTTPS

378

86

87

66

90

76

68

74

75

87

79

74

67

72

72

118

120

120

119

119

117

217

93

94

94

33

92

92

50

51

39

55

48

53

49

54

39

info box

kick

lists

menus

online help

refresh

selection field

selection table

starting

status light

tab list

WebAdmin Site Certificate

creating

installing

introduction

DHCP Server

static mappings

Interfaces

determining MAC addresses

wireless LAN station

IPSec VPN

configuring

configuring a policy

defining remote keys

generate a client/host certificate

Load Balancing

defining rules

Masquerading

defining rules

Microsoft Outlook

creating rules

Packet Filter Rules

setting

Ping

Using

Reporting

Accounting

configuring

SOCKS

Glossary

178

138

142

291

298

304

311

174

35

36

31

32

37

31

30

30

38

34

31

96

96

95

173

268

201

189

323

379

Glossary

user authentication 244

380

Notes

Novell Security Manager Powered by Astaro User guide

Novell

Security Manager Powered by

Astaro

Legal Notices

Novell Trademarks

Third-Party Materials

1.Introduction to the Technology

2.Installation

2.1. System Requirements

, available at

2.2. Installation Instructions

3.WebAdmin

3.1. Info Box

3.2. Tab List

3.3. Menus

3.4. Online Help

3.5. Refresh

4.Using the Security System

4.1. Basic Settings (System)

For the

only passwords consisting of alphanumeric

For the

only passwords consisting of alphanumeric

4.2. Networks and Services (Definitions)

4.3. Network Settings (Network)

available at

4.4. Intrusion Protection

4.5. Packet Filter

4.6. Application Gateways (Proxies)

will record the following three pieces of information for all incoming mail, which is also known as

address of the host it is sent from

The recipient address

This

is checked against the SMTP proxy’s internal database; if the triplet has never been seen before it is created within the database getting a special time stamp

causes the e-mail to be rejected for a period of time of five minutes

If the time stamp is older than five minutes, the e-mail will immediately be delivered and the time stamp will be updated with the current time minus five minutes

4.7. Virtual Private Networks (IPSec VPN)

4.8. System Management (Reporting)

4.9. Remote Management (Remote Management)

4.10.Local Logs (Log Files)

4.11.Online Help

4.12.Exiting the Security System

Glossary

Index

Notes

Related manuals

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Security Manager Powered by Astaro

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mrs 5.0

Multi-Tech

RouteFinder RF850

Multi-Tech Systems

RF760

Astaro

ASGN01201NS

Astaro

AMAC02005

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ASG Mail Security, 50u, 1Y, SUB

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