Atmel Crypto Products REAL.EASY Training Manual

Atmel Crypto Products REAL.EASY Training Manual
CRYPTO PRODUCTS
REAL.EASY TRAINING MANUAL
2nd QUARTER 2015
ATECC508A Crypto Element with ECDH Key Agreement
Table of Contents
1.
Two Families of Atmel Crypto Products ......................................................................... 6
2.
CryptoAuthentication Keeps it Real ............................................................................... 7
3.
SECURITY DRIVES GROWTH ..................................................................................... 9
4.
WHY SHOULD CEOs CARE ABOUT SECURITY? ..................................................... 10
5.
SECURITY MATTERS................................................................................................. 11
6.
EASY TO FIND UNPROTECTED NODES .................................................................. 12
7.
VULNERABITY IS WIDESPREAD .............................................................................. 13
8.
HARDWARE IS BETTER…BUT IT MUST BE PROTECTED...................................... 14
9.
SECURE HARDWARE IS THE BEST APPROACH .................................................... 15
10. ATMEL MAKES IT EASY............................................................................................. 16
11. HARDWARE KEY STORAGE BEATS SOFTWARE KEY STORAGE ......................... 17
12. ALWAYS ASK IF CRYPTO SHOULD BE IN ANY SYSTEM DESIGNError! Bookmark not defined.
13. Uses of Authentication ................................................................................................. 19
14. Why IoT (and everything else) Requires Strong Authentication ................................... 20
15. Why Buy CryptoAuthentication? .................................................................................. 23
16. Real security is all about safe key storage. .................................................................. 24
17. Conditions today are creating a perfect storm for security ........................................... 25
18. Use Cases: Accessory Authentication ......................................................................... 26
19. Use Cases: Medical Device Authentication ................................................................. 27
20. Use Cases: Firmware Authentication ........................................................................... 28
21. Use Cases: Industrial Authentication ........................................................................... 29
22. Use Cases: Consumable Authentication ..................................................................... 30
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23. Use Cases: Automotive Authentication ........................................................................ 31
24. Expanding Solution Coverage ..................................................................................... 32
25. Crypto Basics 1: Symmetric and Asymmetric Authentication...................................... 33
26. Crypto Basics 2: Encryption and Authentication .......................................................... 34
27. Crypto Basics 3: Hashing vs. Encryption ..................................................................... 35
28. Crypto Basics 4: Real Short Glossary ......................................................................... 36
29. Crypto Basics 5: “CIA” The Three Pillars of Security ................................................... 37
30. Symmetric Authentication with secrets stored on the host using Challenge-Response.38
31. Symmetric Authentication without secret storage on the host using a Fixed Challenge39
32. Symmetric Authentication without secret storage on the host using Fixed Challenge and intermediate key. 40
33. Asymmetric Authentication using Digital Signatures (ECDSA) .................................... 41
34. Asymmetric Authentication: Making the ECDSA certificates....................................... 42
35. Asymmetric Authentication: Creating the Client’s Certificate ...................................... 43
36. Asymmetric Authentication: Creating the Signer’s Certificate ..................................... 44
37. Asymmetric Authentication ECDSA is a two phased process (Phase 1, Part 1: Verify Client’s Public Key) 45
38. Asymmetric Authentication: ECDSA is a two phased process (Phase 1, Part 2: Verify Issuer’s Signature) 46
39. Asymmetric Authentication: ECDSA is a two phased process (Phase 2: Verify Private Key)
47
40. Firmware Protection: Secure Boot (Step 1. Making the signature in the factory) ......... 48
41. Firmware Protection: Secure Boot (Step 2. Authenticating the device in the field) ...... 49
42. Protecting Downloaded Firmware with Symmetric Keys; Step1: Encrypt and MAC application code 50
43. Protecting Downloaded Firmware with Symmetric Keys; Step2: Download, Decrypt, and Authenticate
51
44. Symmetric Session Key Exchange (with crypto devices on both sides) ...................... 52
45. Protecting Communication between the Crypto device and MCU. .............................. 53
46. Secure Storage Using Encryption (Symmetric)............................................................ 54
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47. Secure Password Protection........................................................................................ 55
48. Confidentiality using Symmetric Session Key Exchange ............................................. 56
49. Node Data Integrity Using Symmetric Intermediate Keys ............................................ 57
50. Node Authentication Using Symmetric Intermediate Keys ........................................... 58
51. Confidentiality using ECDH Key Agreement ................................................................ 59
52. ATECC508A provides Confidentiality, Integrity, and Authenticity. ............................... 60
53. Security and the IoT ..................................................................................................... 61
54. The Mathematical Magic of ECDH Key Agreement ..................................................... 62
55. Using diversified keys to increase security .................................................................. 65
56. Innovations that make Atmel secure key storage devices robust. ............................... 66
57. Consumption Tracking ................................................................................................. 67
58. Secure Personalization ................................................................................................ 68
59.
Secure Personalization Services ............................................................................... 69
60. Additional Configuration Options ................................................................................. 70
61. Atmel CryptoAuthentication ™ Devices ....................................................................... 71
62. Competitive Advantages .............................................................................................. 72
63. AES encryption in the real world .................................................................................. 73
64. Message Authentication Example ................................................................................ 74
65. Intrusion Detection Feature (ATECC108A & ATECC508A) ......................................... 75
66. Feature Summary of ATMEL ECC CryptoAuthentication devices (ATECC108A and ATECC508A)
76
67. Feature Summary of ATMEL ECC CryptoAuthentication devices (ATECC108A and ATECC508A)
77
68. Atmel CryptoAuthentication ™ Devices: ATECC108A ................................................ 78
69. Atmel CryptoAuthentication ™ Devices: ATSHA204A ................................................. 80
70. Atmel CryptoAuthentication ™ Devices: ATAES132A ................................................ 82
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71. Atmel CryptoAuthentication ™ Devices: ATECC508A ................................................ 84
73. Atmel CryptoAuthentication ™ ECC Device Comparison ............................................ 86
74. CryptoAuthentication Device Selector Guide ............................................................... 87
78. Atmel CryptoAuthentication Device Ordering Guide: ATECC108A .............................. 91
79. Atmel CryptoAuthentication Device Ordering Guide: ATSHA204A .............................. 92
80. Atmel CryptoAuthentication Device Ordering Guide: ATAES132A .............................. 93
81. Atmel CryptoAuthentication Device Ordering Guide: ATECC508A .............................. 94
82. Atmel provides tools for every stage ............................................................................ 95
83. AT88CK490 and AT88CK590 Demo-Evaluation kits ................................................... 96
84. CryptoAuthXplained Pro Development Kit ................................................................... 97
85. AT88CK9000 Production Programming Tool ............................................................... 98
86. “ACES” (Atmel Crypto Evaluation Studio) Software..................................................... 99
87. Atmel CryptoAuthentication Kit Ordering Guide ......................................................... 100
88. Atmel Trusted Platform Module (TPM) ...................................................................... 103
89. Trusted Platform Module (TPM) Security Features .................................................... 104
90. Authentication Using TPM ......................................................................................... 106
91. Secure Boot Using TPM for Platform Integrity ........................................................... 107
92. Atmel Trusted Platform Module (TPM) Device Selector Guide .................................. 108
95. Atmel Trusted Platform Module (TPM) Device Ordering Guide ................................. 111
97. Trusted Platform Module (TPM) Kits .......................................................................... 113
98. Trusted Platform Module (TPM) Kits Selector Guide ............................................... 114
99. Contacts
Error! Bookmark not
defined.
100. FAQs: Some important questions: ............................................................................. 115
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1.
Two Families of Atmel Crypto Products
CryptoAuthentication ™ Device
Family
Atmel offers the industry's widest portfolio
of crypto elements with ultra-secure
hardware-based key storage, to provide
confidentiality, integrity, and authentication.
There are now four industry leading
integrated circuits with several others under
development.
Trusted Platform Module (TPM)
Family
Atmel Trusted Platform Module (TPM)
devices employ ultra secure hardwarebased key storage to implement public key
(RSA) security for PCs, tablets, and
embedded systems. They are complete
turnkey systems on a single device
integrating a microcontroller, EEPROM, and
crypto engines, and are compliant to
Trusted Computing Group TCG 1.2
specification Revision 116.
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2.
CryptoAuthentication KEEPS IT REAL
Atmel’s crypto elements wity hardwarebased key storage ensure that a product,
consumables it uses, firmware it runs,
accessories that support it and, the network
nodes it connects to are not cloned,
counterfeited, or tampered with.
Using cryptographic procedures and
advanced defense mechanisms the devices provide strong authentication
(i.e. “keep it real”).
In addition to authetnication, CryptoAuthentication devices also make it easy
to add the other foundational pillars of security, namely confidentiality and
data integrity, to microprocessor-based systems.
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3.
SECURITY DRIVES GROWTH
IoT, cloud, wearables, vehicle–to-vehicle communications, and mobile market
growth will give rise to billions of smart nodes and platforms.
That multiplies the number of entry points
hackers can attack.
So, robust security is needed.
The Internet’s inventor, Dr. Vint Cerf, says that
strong authentication is important to make
sure that the IoT is talking to the devices they
are supposed to talk to.
We completely agree.
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4.
WHY SHOULD CEOs CARE ABOUT SECURITY?
CEOs will face shareholder and class action lawsuits from data breaches.
Proven means to secure against hacking and cloning exist, there is a
perceived duty to employ them, and not doing so can be argued as being
negligent.
Agree or not, such arguments are already starting to happen.
Some CEOs and CTOs are mandating use
of strong hardware-based security to
protect their companies and get a
competitive edge.
We can see why.
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5.
SECURITY MATTERS MORE THAN EVER
Even with the explosion of data
breaches, security is still treated
as an afterthought.
Security should, in fact, be the
prerequisite of any discussion
about a data system or any type.
Engineers, executives, investors, and researchers alike have been whistling
past the graveyard hoping that their digital interests will not be attacked too
badly.
Of course that is irrational because targets are super easy to find now.
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6.
IT IS EASY TO FIND UNPROTECTED NODES
Traffic lights, security
cameras, home automation
devices, appliances, heating
systems, industrial
networks…you name it… are
now super easy to find
because of Shodan, which is
the Google of embedded
systems.
Shodan searches the
Internet’s back channels 24/7 looking for servers, webcams, printers, routers
and all the other stuff connected to the Internet.
Shodan alone proves that robust security for connected devices is needed
badly because if it is connected, it is vulnerable to hackers.
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7.
VULNERABITY IS WIDESPREAD
Hackers steal passwords, digital IDs, IP,
and financial data because software is
used to protect system software.
But, all software is vulnerable because all
software has bugs.
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8.
HARDWARE IS BETTER…BUT IT MUST BE PROTECTED
Hardware is better, but integrated circuits can
be probed to read what is on the circuit.
Also, power analysis can extract
secrets.
So, a more secure approach is needed.
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9.
SECURE HARDWARE IS THE BEST APPROACH
Hardware-based key storage with physical barriers and cryptographic
countermeasures can fight off even
the most aggressive attacks.
Once keys are locked away in
protected hardware, attackers cannot
see them and cannot attack.
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10.
ATMEL MAKES IT EASY
CryptoAuthentication™ and Trusted Platform
Module (TPM) devices are turn-key, cost
effective, and work with any MCU!
Atmel does the hard cryptographic engineering,
so users don’t need to be crypto experts.
That makes it REAL EASY to add robust
security to any system !
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11.
HARDWARE KEY STORAGE BEATS SOFTWARE KEY STORAGE
An important (Fortune 100) industrial networking company executive said
that not using hardware key storage is like storing your cryptographic key in
a wet paper bag.
He totally gets it.
What about you?
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12.
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13. Uses of Authentication

Anti-Counterfeiting
Validates that a removable, replaceable, or consumable
client is authentic. Examples of clients could be system
accessories, electronic daughter cards, or other spare
parts. It can also be used to validate a software/firmware
module or memory storage element.

Protecting Firmware or Media
Validates code stored in flash memory at boot to prevent
unauthorized modifications, encrypt downloaded program
files as a common broadcast, or uniquely encrypt code
images to be usable on a single system only.

Storing Secure Data
Store secret keys for use by crypto accelerators in
standard microprocessors. The ATECC508A can also be
used to store small quantities of data necessary for
configuration, calibration, ePurse value, consumption data,
or other secrets. Programmable protection is available
using encrypted/authenticated reads and writes.

Checking User Passwords
Validates user-entered passwords without letting the expected value become known, maps memorable passwords to a random number, and
securely exchanges password values with remote systems.
Benefits




Preserves revenue streams from consumables
Protects Intellectual Property
Keeps data secure
Restricts unauthorized access
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14.
Why IoT (and everything else) Requires Strong Authentication
It seems that every day new and increasingly dangerous viruses are infecting
digital systems. Viruses with names such as Heartbleed, Shellshock, Poodle, and
Bad USB have put innocent people at risk in 2014 alone. Russian Cyber gangs
(a.k.a. “CyberVor”) have exposed over a billion passwords. The scary thing is
that the attacks are targeted at the very security mechanisms that are meant to
provide protection. Because the digital protection mechanisms themselves have
become targets, they must be hardened. This is especially important now that
the digital universe is going
through a type of Big Bang with
the explosion of the IoT. That
is sending billions of little
sensing and communicating
processors all over the earth,
like dust. Growth in
processing, communicating, and
sensing semiconductors (which are exactly what the IoT is made from) will grow
at a rate of over 36% in 2015 according to Gartner, dwarfing the overall
semiconductor market growth of 5.7%. Big Bang. Big Growth.
As for security, the IoT will multiply the number of points for infection
that hackers can attack by many orders of magnitude.
It is not hard to see that trust in the data communicated via an ubiquitous (and
nosey) IoT will be necessary for the IoT to be widely adopted. Without trust, the
IoT will fail to launch. There is hardly any doubt there. In fact, the recognized
inventor of the Internet, Vint Cerf, completely agrees, saying that the for IoT
strong authentication is important, and we need to make sure they are talking to
the devices they are supposed to talk to.. Those are very clear statements, but
for fun let’s translate Dr. Cerf’s admonition into pop culture parlance: “No
security? No IoT for you.”
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Why IoT (and everything else) Requires Strong Authentication (Continued)
Lawsuits. But, there is much more to the story behind why the IoT needs strong
security. Because the world has become hyper-connected, financial and other
sensitive transactions have become almost exclusively electronic. Money now is
simply electronic data, so everyone and every company are at risk of financial losses
stemming directly from data breaches. See? Databanks are where the money is kept
and data is what criminals attack. While breaches are in fact being publicized, there
has not been much open talk about their leading to significant corporate financial
liability. That liability, however, is real and growing. So, CEOs should not be the
least bit surprised when they start to be challenged by significant shareholder and
class action lawsuits stemming from security breaches.
Although inadvertent, companies are in fact exposing identities and sensitive financial
information of millions of customers, and they may not always be taking all the
measures that they can to ensure the security and safety of their products, data, and
systems. Both exposure of personal data and risk of product cloning can translate to financial damages. Damages translate to
legal action. The logic of tort and securities lawyers is that if proven methods to secure against hacking and cloning already
exist, then it is the fiduciary duty of the leaders of corporations (i.e. the C-Suite occupants) to embrace such
protection mechanisms (such as hardware-based key storage), and not doing so could possibly be argued as being negligent.
Agree or not, that line of argumentation is logical and perhaps likely.
A few CEOs have already started to equip their systems and products
with strong hardware-based security devices...but they are doing it
quietly and not telling their competitors. This gives them an edge.
Software, Hardware, and Hackers. Why is it that hackers are able to
penetrate systems and steal passwords, digital IDs, intellectual property,
financial data, and other secrets? It is because until now only software
has been used to protect software from hackers. Hackers love
software. Breaking into software is what they live for.
The problem is that rogue software can see into system memory, so it is
not a great place to store important things such as passwords, digital IDs,
security keys, and other valuable things. The bottom line is that all
software is vulnerable because software has bugs despite the best efforts of developers to eliminate them. So what about storing
important things in hardware?
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Why IoT (and everything else) Requires Strong Authentication (Continued)
Hardware is better, but standard integrated circuits can be physically probed to read
what is on the circuit. Also, power analysis can quickly extract secrets from
hardware. So, is there anything that can be done? The answer fortunately is yes.
Three of four generations of hardware key storage devices have been designed to
protect keys with physical barriers and cryptographic countermeasures that ward off
even the most aggressive attacks. Once keys are securely locked away in protected
hardware attackers cannot see them and they cannot attack what they cannot
see. Secure hardware key storage devices like Atmel CryptoAuthentication™ employ
both cryptographic algorithms and a tamper-hardened hardware boundary to keep
attackers from getting at the cryptographic keys and other sensitive data.
Keeping secrets keys secret. The basic idea behind such protection is
that cryptographic security
depends on how securely the
cryptographic keys are
stored. But of course it is of no
use if the keys are simply
locked away. There needs to
be a mechanism to use the
keys without exposing
them. That is the other part
of the CryptoAuthentication™
equation, namely built-in
crypto engines that run
cryptographic processes and
algorithms. A simple example
of accessing the secret key without exposing it is using challenges (usually random
numbers), secret keys, and cryptographic algorithms to create unique and irreversible
signatures that provide security without anyone seeing the secret key.
Crypto engines make running complex mathematical functions easy while at the same time keeping
secret keys secret inside robust, protected hardware. This hardware key storage/crypto engine
combination is the secret to keeping secrets and being easy to use, available, ultra-secure, tiny, and inexpensive
While the engineering that goes into hardware-based security is sophisticated, Atmel does all the crypto engineering so there is no need to
become a crypto expert.
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15. Why Buy CryptoAuthentication?
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16. Real security is all about safe key storage.
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17.
Conditions today are creating a perfect storm for security
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18.
Use Cases: Accessory Authentication
One of today’s main authentication use cases are accessories and consumables. Consumables are sort of like accessories that are bought,
used up, disposed of, and re-bought, again and again. There is a wide spectrum of accessories, particularly for mobile handsets, already
in the market with new ones being introduced all the time. Examples are wired and wireless battery chargers, docking stations,
speakers, wearables, wireless camera lenses, smart covers,
advanced earphones, headphones, and medical diagnostic
sensors. Accessories and consumables present very similar
business models regarding authentication, but consumables will
drive higher volumes due to emerging products.
The constellation of accessories that surround mobile phones,
tablets, computers, GPS units, digital cameras, in-car
entertainment equipment, and other platforms represents a very
large market. According to market research, by 2017 mobile
phone and tablet accessory revenues could reach over $75
billion. Such a sizeable forecast is generating huge incentives for
both bona fide competitors and illegitimate suppliers to jump in.
Hardware authentication is the obvious solution to protect market
share. Safety is another critical issue. There are many recent
instances of batteries exploding or catching fire in mobile and
other products. A bad accessory experience like a fire reflects
not only on the accessory maker but the main platform brand
even more so. Authentication makes certain that only safe
batteries can be used, which is great for consumers and the
legitimate suppliers.
Customers also support this model as the desirability of authentic, uniquely marketed accessories has gained popularity in recent years.
Consumers made weary by cloned products not performing to their expectations are becoming more and more willing to pay the extra
cost of a well designed accessory. CryptoAuthentication is ideally suited for this market, and is enabling manufactures to support
customer trends while providing an exceptional tool to manage their own product lines. In short: Authentication enhances revenue,
brand equity, and safety. And that makes a real difference in the real world.
Benefits





Protects revenue stream
Protects brand image
Allows manufacturers to control third party licenses
Better control of the supply channel
Enhanced product safety
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19.
Use Cases: Medical Device Authentication
Authentication of medical devices is a growing market and it has
started to be driven by government agencies. Governments have
become the main drivers of medical policies and are clearly shaping the
future of medical care. New policies will have enormous impact on the
design, distribution, financing, and use of medical equipment of all kinds.
Looking at where the US government, for example, wants medicine to go
we can see two clearly emerging vectors; namely electronic records and
telemedicine. Both of these vectors point in the direction of
authentication.
Handset/tablet based telemedicine using an array of wired and wireless
diagnostic sensors will help extend healthcare services to underserved
and remote populations. Implantable sensors and devices are already
being programmed wirelessly such as pacemakers and defibrillators, and
the FDA has expressed concern that such products could be interfered
with or hacked with mal-intent. So, in mid-2013 the FDA issued
guidelines for authentication of wireless medical appliances in order to
promote safety. Without a doubt, the last thing a patient with a
pacemaker wants to have to worry about is someone hacking their
heartbeat.
Authentication is also a way to ensure privacy of electronic medical records, which is required by laws such as HIPAA. The mandate for
electronic records went into effect in January 2014. The need for authentication of electronic records will only grow as the systems
continue to roll out and evolve.
Benefits




Secures ecosystems
Improves quality
Tracks charges
Reduces medical liability exposure
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20.
Use Cases: Firmware
Authentication
Firmware in every type of product is
vulnerable to cloning. Using
CryptoAuthentication devices can ensure
that only the authorized firmware is loaded
at boot time. There is a growing trend in
many industries where Intellectual Property
(IP), particularly firmware is being copied,
and the benefits of expensive R&D
investments end up being forfeited by the
legitimate owners. CryptoAuthentication is a
simple and effective way to guard against
firmware and product cloning.
Placing a CryptoAuthentication device
onboard a micro-controlled system provides
a simple solution that can match the secret
stored in the security IC to the operating
firmware. How that can be accomplished
depicted in the secure boot diagrams (shown
later) showing step one where the
application code is signed in the factory and
step two where it is verified by the Crypto
device before launching the application.
Benefits


Prevents cloning
Protects investments in firmware
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21.
Use Cases: Industrial Authentication
Authentication in the industrial space is very
much like the consumer accessories and
consumables segment. An embedded
system in an industrial setting will also have
various “things” that it connects to and uses.
Examples are sensors, firmware, chucks,
tooling, counters, actuators, motors, fittings,
control panels, power sources, batteries,
spare parts, bits, dies, blades, materials,
safety items, chemicals, authorized users,
access points, I/O blocks, conveyors, valves,
illumination…well, you get the picture.
The point is that industrial applications are
not only very technical but widely variable,
which means that there are numerous
opportunities for adding authentication
devices in industrial settings. Doing so
enhances safety, tracks items, fights cloning,
protects firmware, and ensures the source of
spare parts, among other things.
Benefits




Prevents cloning
Protects investments in firmware
Enhances safety
Tracks items
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22.
Use Cases: Consumable Authentication
The food chain for crypto devices used in
a consumable product is illustrated in the
picture. Finished crypto devices are
shipped from the factory with the
customer’s programming sealed in. This
programming includes the stored secrets
and operational programming. The
customer’s programming is also called
“personalization” because it is specific to
that customer (i.e. it is configured
according to their design) . The crypto
device is delivered to the customer’s
factory or assembly facility and either
soldered to a PCB or glued to the surface
of a product using the 3-contact RBH
package. The PCB or the device itself (in
the case of the RBH package) is attached
inside or to the surface of the
consumable). That consumable product
then gets inserted into the host system,
which can be a printer, refrigerator,
medical device, or any number of
products. That product when exhausted
gets replaced in the field. When the
consumable is put into the host system
the authentication process gets initiated and lets the host know if that consumable is real or not.
Benefits






Prevents cloning
Protects investments in firmware
Enhances safety
Protects revenue stream
Protects brand image
Better control of the supply channel
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23.
Use Cases: Automotive
Authentication
With Vehicle-to-Vehicle (V2V) and Vehicle
to Internet (V2I) communications cars
will “talk and listen” to one another —
automatically. They will share information
like proximity, speed, direction, road
conditions, and sense other cars,
motorcycles, and pedestrians. The chief
driver of V2V is signaling impending
collisions so that the cars can
automatically take countermeasures.
While it may seem revolutionary, V2V is really a branch of Internet of Things (IoT). Describing IoT and V2V as equations, they
could be expressed in the following way:
IoT = (MCU + Sensor + Security + Wireless) Low Power
V2V = IoT + Car
Equation two states that V2V is really the IoT on wheels. However, this spread of electronic devices presents a huge challenge,
which is safety. Safety can be compromised by hackers interfering with V2V communications and hacking into automotive control
systems. Safety and security are closely related. Clearly there needs to be strong security on ALL systems in cars. The US
Department and Transportation (DoT) and National Highway Traffic Safety Administration (NHTSA) are partnering with research
institutions and auto companies to collaborate on technology development and interoperability of V2V to promote traffic safety.
V2V can transform the automotive experience. The danger is that remote communication opens the door for hackers who want to
intercept, spoof, and misuse data. So, strong security becomes the final piece of the picture, and arguably the element that makes
IoT/V2V even possible to be widely adopted. Of course the strongest form of security comes from hardware-based key storage.
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24.
Expanding Solution Coverage
CryptoAuthentication devices cover parent-child and peer-to-peer application platforms. This means that there is a solution for
all types of host-client and peer to peer relationships. Typically authentication has been parent to child, but with the IoT and car
to car communication that is changing very rapidly. IoT, for example will have both hast-client and peer-to-peer requirements.
The flexibility of the CryptoAuthentication portfolio presents valuable flexible options to designers.
Benefits

Covers range of parent-child and
peer-to-peer solutions

Perfect fit for new applications, such
as Car 2 Car, smart covers,
mobile batteries, IoT, etc.

Ideal way to comply with evolving
governmental regulations driving
such as medical authentication and
V2V
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25.
Crypto Basics 1:
Symmetric and Asymmetric Authentication
Authentication can be accomplished in two main ways:
Symmetric and Asymmetric. The main difference
between the two is related to the use of keys. If the
same secret key is used on the client and also on the host
then the application is symmetric, just like the name
indicates. Remember if the keys are equal then the
system is symmetric. Alternatively, if there is a
mathematically related private and public key pair being
used then the application is asymmetric. If the keys are
not the same on each side then it is asymmetric. Atmel
has devices for both types.
Asymmetric, asymmetric is also called public-key
infrastructure or “PKI” and it is very well suited for realworld use. In fact, the internet is a big user of PKI. Note
that Public Keys indicate that the system will be
Asymmetric. Like is sounds, a public key is available to
anyone. Think of a phone book filled with keys when
envisioning the public key. Anyone having the public key
can send encrypted messages to the owner of the private
key. When a receiver gets an asymmetric message, he or she will decrypt it with their private key. In contrast, because
symmetric cryptography uses the exact same key for both encryption and decryption, only the senders and receivers with that
specific private key can communicate to each other. In addition to such differences in who can send and receive, other tradeoffs between symmetric and asymmetric apply. For example, for symmetric at least twice the number of keys must be protected,
increasing security risk. On the other hand, Asymmetric algorithms require more processing and thus are slower than symmetric.
So, sometimes a combination of both symmetric and asymmetric is used to apply the relative advantages of each: the speed of
symmetric and the security of asymmetric.
Benefits



Verifies the identity of the sender and the integrity of the data
Symmetric authentication can be fast
Asymmetric authentication does not need secret storage in the host
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26.
Crypto Basics 2: Encryption and Authentication
Encryption and authentication are fundamental security functions, but have different purposes.
Encryption, from the time of Julius Caesar until now, has been used to protect messages from being read by unintended people.
Authentication is the other main pillar of cryptography, and just like its name implies, authentication is about making sure that
something is real.
In the cryptography world authentication is used to see if a message is real. To make such a “reality check” a number of things
have to be verified such as if it was sent by the
right sender, if messages were received in the
right order, if the intended message or part of
the message was deleted, or if a message was
altered in some way. It doesn’t matter if an
encrypted message is decrypted accurately if it
was not the intended message to begin with, or
if it was altered. In short, encryption is about
encoding and decoding, while authentication is
about verifying the identity of the sender and
the integrity of the message.
Benefits

Encryption keeps the message secret so
only authorized receiver can see it.

Authentication ensures the identity of the
sender and integrity of the data

Authentication and encryption can be used
together for more security
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27.
Crypto Basics 3: Hashing vs. Encryption
One of the basic tools used in authentication is a
mathematical operation called a “hash function”.

A hash function is defined as a group of characters that is mathematically
mapped to a value of a certain length (called a hash value, hash, compression,
fingerprint, message digest, or simply digest).

The hash value is representative of the original string of characters, but is
normally smaller than the original
Hashing functions have been used by computers for a long time and they
are fundamental to cryptography. The hash value is representative of
the original string of characters, but is normally smaller than the original.
A hash is a one-way operation. The “one-wayness” of a hash function is
its most important feature for cryptography because it is mathematically
infeasible to reverse the hashing process to obtain the original message.
A way to look at is that once the message is compressed it is impossible
to uncompress it. Sort of like Humpty-Dumpty, you can’t put it back together again. Also, a feature of a hash function is that any
change to the input changes the digest, so hashes are great to create digital signatures that identify and authenticate the sender and
message. Hashes are also used for secure password storage, file identification, message authentication coding (MAC), and asymmetric
sign verify operations. Encryption is a different process from hashing and has a separate purpose.
With encryption, data is scrambled and unscrambled in such a way that the input and output
mapping is always one-to-one for a given key and is unintelligible to anyone other than a receiver
who has the key to unscramble it. Encryption is always reversible (by definition), so encryption is
used whenever there is the need to get the input data back out. However, the identity of the sender
and the integrity of the message (meaning if it has been altered or not) are not guaranteed by
encryption only. That is where authentication comes in. Authentication and encryption are two
distinct and critical parts of strong cryptography.
Benefits



Encryption algorithms are useful for coding and decoding messages
Hash algorithms cannot be reversed (i.e. are one-way so the original value cannot be derived)
Hashes are useful for checking the identity of the sender and the integrity of the data
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







Crypto Basics 4:
Real Short Glossary
Encryption is encoding and decoding of a message for confidentiality. It is always reversible. Encryption does not authenticate.
Authentication is used to check the identity and of the sender and the integrity of the message. The message is not necessarily encrypted.
Symmetric authentication uses an identical key on the host and client sides, and both of those keys must be protected (this is very important).
Symmetric authentication tends to be relatively fast.
Asymmetric authentication uses a public / private key pair. The private key must be securely stored on the client. Secure key storage on the host
is not needed. The keys are mathematically related, but the private key cannot be obtained from simply having the public key. More computation is
required with asymmetric authentication than symmetric.
Key Storage is one of the most important determinants of the strength of security in a system. Hardware key storage is much stronger than
software-based solutions because hardware storage methods are much more difficult to attack. (CryptoAuthentication ICs are hardware key storage
devices.)
Hash functions are a group of characters that is mathematically mapped to a value of a certain length and is representative of the original string of
characters, but is normally smaller than the original. Hash functions are commonly used in authentication and encryption operations. They are one
way functions which means that the original value cannot be recreated from the hashed value (i.e. digest).
Challenge-Response is an operation where a challenge (usually a random number) is sent to a client to elicit a response in order to test the
authenticity of a client. The response is often a hash value of that number another number such as a cryptographic key. The response is then
compared to a parallel calculation done on the originating device to see if they match..
MAC (Message Authentication Code) uses a secret key and cipher algorithm (e.g. SHA-256) to produce a value (called the MAC) which can
be used to ensure the data has not been modified. The response of a challenge-response is a MAC.





Sign/Verify is an authentication operation that creates a hash digest of data, which is then encrypted using a private key to make a signature.
To verify, the receiver hashes the received data and then decrypts the received signature of that data with the sender’s public key. If the
signature received from the sender matches the hash that the receiver generated with the public key, then the signature is considered valid.
ECDSA (Elliptic Curve Digital Signature Algorithm) an elegant and standardized method to provide asymmetric authentication using a sign-verify
process using Elliptic Curve (ECC) algorithms to make a signature. ECDSA has two phases which are 1) to verify the public key, and 2) verify the
private key of the client (i.e. accessory) device. ECDSA capability is built into the Atmel ATECC108A device. X.509 is an ITU standard that specifies
what goes into the certificate.
ECDH Key Agreement (Elliptic Curve Diffie-Hellman) an elegant and standardized method to provide asymmetric authentication using a sign-verify
process using an anonymous key agreement protocol that allows two parties, each having an elliptic curve public–private key pair, to establish a
shared secret over an insecure channel. This shared secret may be directly used as a key, or to derive another key which can then be used to
encrypt subsequent communications using a symmetric key cipher. It is a variant of the Diffie–Hellman protocol using elliptic curve cryptography.
Root certificate is a public key certificate that identifies the Root Certificate Authority (CA). The most common commercial variety is based on
the ITU-T X.509 standard, which normally includes a digital signature from a certificate authority. .Digital certificates are verified using a chain of trust.
The trust anchor for the digital certificate is the Root Certificate Authority (CA).
Public-key cryptography, is a class of algorithms which requires two separate keys, one of which is secret (private) and one public. This key pair is
mathematically linked by algorithms that are computationally infeasible to determine the private key from the public key. The public key is used
to encrypt plaintext or verify a digital signature. The private key is used to decrypt ciphertext or to create a digital signature. The term "asymmetric"
stems from the use of different keys to perform these opposite functions, each the inverse of the other – as contrasted with conventional
("symmetric") cryptography which relies on the same key to perform both. Public-key algorithms are based on mathematical problems which
currently admit no efficient solution that are inherent in certain integer factorization, discrete logarithm, and elliptic curve relationships.
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29.
Crypto Basics 5: “CIA” The Three Pillars of Security
To provide the full set of security you will need all three
of the foundational pillars of security: Confidentiality,
Integrity (of data), and Authentication. These can be
remembered as “CIA”:
Confidentiality
This is ensuring that no one can read the
message except the intended receiver. This is
typically accomplished with encryption and
decryption which hides the message from all
parties but the sender and receiver.
Integrity
This is also called data integrity and is assuring
that the received message was not altered.
This is done using cryptographic functions. For
symmetric this is typically done by hashing the
data with a secret key and sending the
resulting MAC with the data to the other side
which does the same functions to create the
MAC and compare. Sign-verify is the way that
asymmetric mechanisms ensure integrity.
Authenticity
This is verification that the sender of a message is who they say they are (i.e. are real). In symmetric authentication mechanisms this is
usually done with a challenge (often a random number) that is sent to the other side that is hashed with a secret key to create a MAC
response which then gets sent back to run the same calculations and then compare the response MACs from both sides.
Sometimes people add non-repudiation to the list of pillars which is preventing the sender from later denying that they sent the message in
the first place.
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30.
Symmetric Authentication with secrets stored on the host using Challenge-Response.
With Symmetric Authentication using secrets stored on the host using Challenge-Response, like you might expect from the name, the host sends a
challenge and the client makes a response using cryptographic “magic” (i.e. math) and then the host runs the same process in order to make a
comparison to see if it gets the same
answer. It the answers on each side
match then the client is real.
The process starts when the host
sends a random number, which is
generated by the ATSHA204’s
random number generator to the
client. It does this at the time that it
wants to verify if the client is real
such as when an ink cartridge is
inserted into a printer. This step is
called the “Challenge” and is shown
as step one. The client receives the
random number challenge and runs it
thru a hash algorithm (SHA256)
using the secret key stored there.
The result of the hashing function is
called the “Response” and also
called “Message Authentication
Code” (or MAC). The response is
then sent to the host, and together
these actions comprise step two.
Moving to step three, the host
internally runs the same challenge
number (i.e. the random number) it
sent to the client thru a hash
algorithm using the secret key stored on the host side. Then the host compares the hash value calculated on the host side with the response hash
value sent from Client. If the two hash values match then the Client is verified. And that is how to do symmetric verification using the ATSHA204 on
both sides.
Benefits


Symmetric authentication is fast
Crypto devices on both host and client sides ensures very secure secret storage
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31.
Symmetric Authentication without secret storage on the host using a Fixed Challenge
Symmetric authentication can also be
accomplished without having a crypto device on
the host side.
Such an arrangement is called is fixed challenge. That
means that the host does not use a random number,
but instead use a fixed number pair, or series of pairs,
of specific challenge and response numbers that are
programmed into the host’s memory. To calculate the
response value each challenge value is run through a
hash algorithm using the same secret key (or keys) in
the target client (or clients). The challenge and
corresponding response values are loaded and stored
on the host.
When the host sends its preloaded challenge to the
client to check if the client is real or not (which is step
1), the client will run the hash algorithm on that
challenge number and generate a response.
It then sends that response back (which is step 2).
The host will compare the response from the clients
with the pre-loaded response value stored in its
memory (which is step 3).
If the client is real then the response from the client
(which is the hash value based on the secret key and
the challenge) will be the same as the response value that was preloaded in the host. This approach can be used for firmware protection, designs
with no secrets in the host (as noted), and can be implemented with very low cost MCUs.
Benefits



Symmetric authentication is fast
No secrets in the host
Can use low cost MCU of host because less computation is needed for a fixed challenge
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32.
Symmetric Authentication without secret storage on the host using Fixed Challenge and
intermediate key.
Fixed challenges are great if low cost micros
are desired, however, some security is
sacrificed since a logic analyzer can be
employed to break the security. Fortunately,
there is an easy way to add more security to
fixed challenge scenario, and that is by using an
additional hashing stage with an intermediate
key. The process starts with the challenge that is
compiled into the MCU’s software. That
challenge is hashed with the secret key stored on
the client creating the intermediate key. The
intermediate key is then hashed with a unique
number such as a random number or the datetime-etc. from issued by the MCU. That unique
number is used just once and therefore it is
called the “NONCE”, which means number used
one. The hash of the intermediate key and the
NONCE becomes the client’s response. That
response is compared to a digest on the MCU
(.i.e. “MCU Digest”) which is created on the MCU
using the NONCE which gets hashed with the
intermediate key compiled into the MCU’s
software. The MCU Digest will match the Client
Digest (i.e. Response) if the client is real.
Note that the response will change each time
since the NONCE is different each time, and that is what makes this more secure. Trying to analyze the responses with a logic analyzer will be
fruitless.
Benefits


Cannot be attacked with a logic analyzer
Increased security
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33.
Asymmetric Authentication using Digital Signatures (ECDSA)
In the real world the Asymmetric Authentication process typically begins when a client
device is inserted into a host system or the host system wants to know what exactly is
connected to it. Examples are a printer ink cartridge being inserted into a printer, a
thermostat control block wanting to talk to a remote temperature sensor, a cell phone
connecting to a wall charger, and many others.
The best way to understand how ECDSA performs authentication and how it
ties that back to the root of trust is to break it down into its individual steps.
Admittedly, there are many steps but each one does a very specific and simple
thing, so it is easy to follow. To simplify the process, it is useful to group the
steps into sequential phases that perform distinct objectives in the process.
Fortunately, there is a clear break between two major objectives, so we can
break it into a phase one and phase two.
Phase one’s goal is to use ECDSA calculation algorithms to verify the
public key on the client. Phase one has a second goal which is implied,
and that is to verify the entire certificate chain back to the root of trust (i.e.
the certificate authority or “issuer”). One way to look at it is that the host MCU must identify and confirm the entire history of
who signed what. (In this example we will look at a two level signing history going from the issuer to the signing module to the
client device.)
To accomplish the verification of the public key in phase one it is necessary to verify all the signatures in the certificate chain. In
this example the signatures are stored in the client in two distinct digital certificates. One is the client’s certificate and the other is
the signer’s certificate. The certificates are the mechanism that allows the chain to reach back to the root of trust (i.e. the issuer).
Phase two’s goal is to use ECDSA calculations to verify that the private key on the client is related to the previously
verified public key. Verifying that the client has a valid public-private key pair is the soul of symmetric authentication. If the
ECDSA verify calculation operations of both phases pass then the client is verified as real. And that is the whole purpose.
Benefits



Increased security because asymmetric authentication does not need secure key storage on the host (only the client)
No need to update the host with secrets in the field. (Can update the public key at any time.)
ATECC108 has ECDSA built in, making it easy to implement.
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34.
Asymmetric Authentication:
Making the ECDSA certificates
To understand the ECDSA process it is very helpful to first look at how the certificates are built and loaded into the crypto device. This happens in the
factory.
A certificate is made from two
components:
1) The certificate data
2) The signature.
The client certificate creation process begins
in the factory on the machine that tests the
crypto device: in other words, the tester.
Attached to the tester is equipment called
the “signing module” that contains its own
secret private key. That private key is
securely stored and never shared. The
signing module is used to create the
signature, just as its name implies. Once
the certificate is made it is loaded into the
device.
Now let’s look at those steps:
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35.
Asymmetric Authentication:
Creating the Client’s Certificate
First, let’s look at the creation of the certificate data.
The certificate data is made up of three items: 1) static data, 2)
dynamic data, and 3) the client’s public key. You can look at the
static data as a type of boilerplate that contains basic information
such as the company’s name, address, and other information that
never changes. In contrast, dynamic data from the tester are data
that generally change with each part or group of parts being
tested. Dynamic data include things like the serial number, date,
time, expiration date, and so on. The client’s public key is the third
item that goes into the certificate data. Recall that the client’s
public key is paired to the private key of the client device. The
private key is securely stored in the ATECC108 and never shared
(which makes it private). Now the process moves to making the
signature.
Recall that the certificate data comprises just half of a
certificate. The other half is the signature. What is a
little tricky to understand at first is that the certificate
data have two purposes when it comes to building the
certificate: (1) to become part of the certificate, and (2)
to get hashed and then run through a signing algorithm
to produce the signature. Both the certificate data and
the signature made from that certificate data make up
the complete certificate, and that is a major point to
remember. You can see the two purposes of the
certificate data clearly in the diagram, which shows how the certificate data are assembled and stored in the certificate and then also
digested and input to the signing process on the signing module.
As for the details, the signature process begins with a copy of the certificate data being put through a hash algorithm to create a number
called a hash value (or digest). ECDSA P-256 specifies a 32 byte digest length and SHA256 as the hashing algorithm. Once created, the
digest is ready to be signed by the sign module in the factory.
The sign module is a piece of equipment that securely stores the signer’s private key. Being securely stored means that no one can get
access to that key. The sign module uses the ECC sign algorithm to sign the digest of the certificate data with the signer’s private key.
The result of that process becomes the “signature” of the certificate data that went into the singing module and signed with the private
key of the module. The signature then joins the original (i.e. unhashed) certificate data to complete the certificate.
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36.
Asymmetric Authentication:
Creating the Signer’s Certificate
Another certificate called the signer’s certificate is used to create the link to the certificate authority
(issuer). The signer’s certificate is made by the issuer creating a signature over the signer’s
certificate data that it receives from the tester. It signs the data using its (i.e. the issuer’s) private
key. Both the signer’s and client’s certificates are stored in the ATECC108A device. The signer’s
certificate is made by the tester’s assembling the signer’s certificate data and placing it into the
certificate, and then hashing signer certificate data and sending that digest to the certificate authority
(issuer) to be signed with the issuer’s private key. Once created, the signature is sent back to the
tester to be inserted into the signer’s certificate alongside the signer’s certificate data. That
completes the singer’s certificate. The public key of the issuer that corresponds to the issuer’s private
key gets sent to the MCU to use later during the actual authentication process. Both certificates are
now finished and can be securely installed into the crypto device by the tester.
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37.
Asymmetric Authentication
ECDSA is a two phased process (Phase 1, Part 1: Verify Client’s
Public Key)
ECDSA is a two phased process with phase one being to verify both the client’s and signer’s public keys. Phase one links (i.e.
chains) the client’s and signer’s signatures back to the issuer’s signature, which establishes the root of
trust (i.e. ties to the anchor).
Phase two’s purpose is to verify the client’s private key. When each of the keys are verified it is proven
that there is a valid client public and private key pair, and that they tie back to the root of trust. In
short, that means that the client is mathematically verified as being real (i.e. authenticated).
Phase 1 starts with the host requesting
information to be sent over by the client
(accessory). That information comes over to the
host in the client’s certificate and in the singer’s
certificate. When the host receives the
certificates, it extracts the client’s certificate data
(client’s static data, client’s dynamic data, and
client’s public key) and the signature made by
the signing module in the chip factory) from the
client’s certificate. It also extracts the signer’s
certificate data (including the signer’s public key)
and the issuer’s signature that was made by the
certificate authority (the issuer). The host runs a
hashing process on the both sets of certificate
data that it just received, creating two 32-byte
message digests (P-256 curve): 1) the client’s
digest, and 2) the signer’s digest.
The extracted signer’s public key that came over
in the signer’s certificate is input to the ECDSA
verify calculation together with the client’s digest
(number 1 above) and the client’s signature
extracted from the client’s certificate. The
purpose of this ECDSA calculation is to verify the
client’s public key.
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Asymmetric Authentication:
ECDSA is a two phased process
(Phase 1, Part 2: Verify Issuer’s Signature)
Before the prior phase one ECDSA calculation can be accepted as complete verification of the
client’s public key, another ECDSA calculation (phase 1, part 2) must be run to verify that the
root of trust exists. The root of trust is established by linking of the signer’s signature to the
issuer’s signature. This is done by verifying the issuer’s signature that came over in the signer’s
certificate.
To do so, the signature in the signer’s
certificate (which is the issuer’s
signature) is input to the second ECDSA
calculation along with two other inputs:
1) The digest made by hashing the
signer’s certificate data, and
2) The issuer’s public key that came
over to the MCU at some earlier point
(and was stored in memory of the
MCU).
If both ECDSA calculations pass then the
client’s public key is considered to be
verified all the way back to the root of
trust (i.e. the issuer).
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Asymmetric Authentication:
ECDSA is a two phased process (Phase 2: Verify Private Key)
When both phase 1 ECDSA calculations pass, then phase 2 starts with the goal of verifying the
client’s private key. Recall that the whole point of this two-phased process is to verify
mathematically that the client’s private key and public key are indeed a valid key pair and tie back
to the root of trust.
Phase 2
This phase begins with the host generating a random number challenge and sending it to the
client. The client device uses the ECDSA signature engine in the ATECC108A to create a new
signature using this random number and the client’s (secret) private key securely stored
there. That new signature is then sent to back the host, which
uses it along with the same random number used to make the
signature and the client’s public key (that was verified in phase
one) as the inputs to the Phase 2 ECDSA verify calculation. If that
ECDSA calculation succeeds, then the host has then proven that
the accessory (client) is real (i.e. that the client contains a valid
private-public key pair). As you can see, the ATECC108A does all
the heavy mathematical lifting.
In addition, Atmel provides the tools that Atmel provides make it
easy to program the microcontroller to do its part without having
to securely store a secret. That is the whole reason for
asymmetric authentication: the secret only has to be secured on
one side.
The engineering and mathematics behind authentication using
sophisticated algorithms may not be easy, but that does not
matter to the user because Atmel makes it easy to implement
cryptography without having to be a cryptography expert.
Benefits


ECDSA is a proven and secure authentication process

No need for secure key storage in the host
Uses the advantages of Elliptic Curve Cryptography (high security ,
short key, less computation)
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Firmware Protection: Secure Boot (Step 1. Making the signature in the factory)
Authentication is useful for many applications, such as securing data storage by encrypting stored data with unique key for each file.
Another application is authenticating stored data such as the manufacturer’s serial number, manufacturing data logs, configuration
parameters, and calibration data. CryptoAuthentication devices are ideal for implementing secure session key exchange because the
private (secret) key never leaves the
security device allowing the host MCU
to encrypt the data stream with
ephemeral session key.
CryptoAuthentication is one of the
most secure ways for handling
passwords because comparisons are
made internally, so attackers cannot
find the expected value, also
passwords can be mapped to a highentropy (i.e. highly randomized)
key(s).
Step 1 is the signing of the
application code in the factory. The
code and the signature is sent to the
embedded system in the field and
loaded into the system memory.
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41.
Firmware Protection: Secure Boot (Step 2. Authenticating the device in the field)
Step 2 is the process of using
the signature and the code
itself at boot time to
authenticate the code (i.e. to
check if it is real). The basic
idea is to use the crypto
device like the ATECC108A to
create a signature of the code
just like was done in the
factory and then compare that
new signature with the one
from the factory. If those
two signatures match then the
code is proven to be the same
as the original code (i.e. not
altered or fake) and is
considered real and thus can
be loaded.
Benefits
 Secure boot using a crypto
device can protect IP and revenue streams
 Easy to implement very strong security
 Numerous applications
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42.
Protecting Downloaded Firmware with Symmetric Keys; Step1: Encrypt and MAC application
code
Software and firmware IP protection possibly provides the largest opportunity application target market. This segment includes anyone that has an
embedded system or software solution. And,
that is just about anyone that has a processor in
their system.
Most systems use nonvolatile memory to store
programs to remotely add features and fix
problems, but they are vulnerable to hacking.
That is because all software based systems can
be hacked. CryptoAuthentication devices
protect downloaded firmware by preventing
hackers from getting software images and
algorithms. This ensures that only unmodified
OEM-authorized firmware gets loaded in
nonvolatile memory. The usage models are
flexible. All downloads will be identical and the
user can post download on the web without
concern of theft because the firmware will be
encrypted.
Two cryptographic pillars are used in this case:
encryption and authentication. Encryption
allows the software IP to be sent to target users
without others being able to use it. It will of
course be decrypted on the other side.
Authentication is then used to ensure that the
code once decrypted is indeed the intended
code. To encrypt the original application code
the developer will need to create an encryption
key. This is done using an ATSHA204 that
stores secret key and hashes it with a seed
number. The digest or Message Authentication Code (MAC becomes the encryption key that is input to the encryption algorithm. The developer then
encrypts the code which is now ready to be downloaded by the target user. The seed number will be sent with the encrypted code to allow decrypting by the
target user. The other pillar (authentication) is prepared by hashing (or padding) the original application code to size it correctly to be hashed with the secret
authentication key, which is a different key than used earlier fro encryption. The result of the hash of the digested (or padded) application code with the
authentication key is the Authentication MAC. That MAC gets downloaded with the encrypted code and seed number.
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43.
Protecting Downloaded Firmware with Symmetric Keys; Step2: Download, Decrypt, and
Authenticate
The target user of protected firmware will download the encrypted code, seed number, and Authentication MAC. To decrypt the code the seed is hashed
with the secret decryption key stored in the ATSHA204 on the client embedded system. Being symmetric, this key has the same value as on the system the
developer used for encryption. The result of that hashing process will be the decryption key, which of course matches the encryption key. The embedded
system decrypts and recovers the application code
using that key.
The process then moves to the authentication stage.
The newly decrypted code is hashed (or padded) just
like was done by the developer on the other side to
prepare for hashing with the secret authentication
key. Of course that key is the same as the
authentication key the developer used, being
symmetric. The result of that hash is the Client’s
Authentication MAC. It will be compared (using the
CheckMAC command) to the Authentication MAC
that was downloaded at the same time as the
encrypted code and seed, and if the two
Authentication MACs match then the downloaded and
decrypted code is authenticated.
Benefits

Can have special downloads for each
customer by tying use to specific authorized
serial numbers.


All downloads will be identical
The user can post the download on the web
because it will be encrypted
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44.
Symmetric Session Key Exchange (with crypto devices on both sides)
The idea is to create a key that changes with each session. That is why is called a session key, of course. Hashing a key with the random number
creates a 32 byte Message Authentication Code or “MAC”. 16 bytes of that 32 byte (256 bit) MAC from the SHA204A becomes the AES session key
that gets sent to the MCU to run the AES encryption algorithm over the data that is to be encrypted.
The newly encrypted data and the random number are then sent over to the other side so the data can be decrypted. Of course, to decrypt the
message the same key that was used to encrypt it must be used in the decryption process. That is exactly why the random number is sent over, to
recreate the session key from that random number and the key stored on the SHA204 on the decryption side. That is done by the random number
being input to the SHA-256 hashing algorithm together with
the key stored on the SHA204A. Because this is a
symmetric operation the secret keys stored on the SHA204A
devices on both sides are identical. So, when the same
random number is hashed with the same secret key, then
the 32 byte digest that results will be the same on the
receiver (decrypting) side and on the sender (encrypting)
side. Just like on the encrypting side, 16 bytes of the hash
(i.e. MAC) represent the AES encryption/decryption key and
will at this point be used to decrypt the message on the
receiving side’s MCU running the AES decryption algorithm.
Benefits

Changes key for each session so keys are not
used for very long which increases security


Very simply yet secure methodology
Easily implemented with ATSHA204A devices
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45.
Protecting Communication between the Crypto device and MCU.
The question often comes up about how to ensure that the communication between the crypto device and the host MCU is not attacked by a manin-the-middle.
This can be accomplished by performing an authentication
on the result of CheckMAC function. The idea is to make
sure that when the authentication device puts out the
Boolean response from the Check MAC that response is not
able to be tampered with.
From the diagram you can see that upon the CheckMac
returning a response a second key (KEY 2) is loaded
immediately into TempKey to that a second comparison can
be made using a Unique number from the MCU that is
hashed on the MCU and the authentication device (with KEY
2) and then compared.
All the devices have this method of protecting the single
Boolean bit that comes from the authentication chip to the
microprocessor.
It involves using a second key that is both stored in the
CryptoAuthentication device and compiled into the code.
After the successful completion of the ‘Check’ operation, the
second secret is copied into the TempKey register. Then the
micro sends over a unique number (call it time of day), which
is then combined with that second secret using SHA and
returned to the micro. The software on the micro does the
same combination using the compiled secret to see if it
agrees with the result from the authentication device. This is
beneficial, because it means that you cannot just put a simple switch in the wire between the two and ‘always send a 1’.
Benefits



Provides complete security between the MCU and crypto device
Capability built into every CryptoAuthentication device
Simple to implement
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46.
Secure Storage Using Encryption (Symmetric)
Hardware key storage devices can be
used to encrypt files. The advantage
is that the encryption-decryption key
is securely stored in protected
hardware as opposed to being stored
in software that is inherently hackable
(because all software is hackable).
The encryption process in this
example is AES (Advanced
Encryption System) and the files were
encrypted using a particular seed
number that was hashed with the
secret key stored securely at the
encryption site. The hash of the
secret key and seed created the AES
decryption key used by the AES
algorithm to encrypt the files.
To decrypt the encrypted files, the
seed number is sent to the
CryptoAuthentication device that
securely stores the same secret. The
crypto device hashes the seed and
the secret to re-create the AES
encryption-decryption key that is then
used by the system MCU to decrypt
the stored file into clear text
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47. Secure Password Protection
To ensure that a password that for
example is typed into a system is not
intercepted, an authentication process is
very useful. One example of how this
can be done is to instruct that the
CryptoAuthentication device sends a
random challenge to the system MCU at
the time the password is being entered.
That random challenge then gets hashed
with the password to create a response
digest. The response digest gets sent to
the crypto device which also hashed the
same random challenge and the
password with is stored in a key slot on
the device. The stored password and
random challenge number are hashed to
create a digest which is compared to the
response digest made on the MCU, If the
digests match then the password is
considered
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48.
Confidentiality using Symmetric Session Key Exchange
Confidentiality is making sure that the message cannot be seen by an
unintended party. The method used is encryption and decryption based
upon a selected algorithm, which in this example is Advanced Encryption
System (AES). To perform encryption and decryption, both sides need
the same encryption/decryption key which is input to the algorithm on
each side. The trick is to produce the key in each side in a way that
does not allow anyone else to obtain it. An excellent way to do that is to
create a new key for each communication session by sending
information that only the intended parties can use to create the keys.
The fact that a new key is created for each session increases security
greatly. This method is not surprisingly called session key exchange.
This is what we will now describe.
The example here is symmetric key exchange, meaning that the session
keys on each side will be the same. To exchange symmetric session
keys in platforms where it is not possible or desirable to securely store a
secret key in the host, a method that preloads challenges and
intermediate keys in the host is recommended. This can be called a
“fixed challenge” method.
The process starts with a challenge number that was loaded into the
host’s software being sent to the remote node (Step 1). The node has a
secret key stored there (in the ATSHA204 or ATECC108 device). This
secret key is hashed with the challenge send over from the host to create
a digest (Step 2). Let’s call that the encryption intermediate key. The host side has that very same intermediate key already loaded in its software. The
host’s intermediate key was created using the same hash algorithm with the same challenge and same secret key as on the client. That process occurs on
tester in the factory. The tester securely stores the secret key and the only the calculated intermediate key is released. The secret key stays in the factory
and stays secret. Once the hashes are run on the tester to make the intermediate keys, the challenges and corresponding intermediate keys are made
available to be compiled into the host’s software. Now both sides have the same intermediate key, which will be used to create the session keys on each
side.
To create the session keys, the host sends a random number to the node (Step 3), and the node hashes that random number with the intermediate key that
was created in Step 2 to form the Encryption Session Key (Step 4). The session key can now be input to the encryption algorithm to encrypt the original
message, which gets sent to the host (Step 5).The host hashes the intermediate key in its software with the same random number it sent to the node to form
the identical session key as on the Node called the Decryption session Key (Step 6). That key is used to decrypt the message that was sent over from the
Node. That completes the process.
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49.
Node Data Integrity Using Symmetric Intermediate Keys
To provide node data integrity in a platform where it
is not possible or desirable to securely store a secret
key on the host, a fixed challenge method using an
intermediate key is recommended. A fixed
challenge is a known number that has previously
been loaded into the host’s software (as opposed to
a random challenge where the challenge is a
random number). To start the process the challenge
number is sent by the host to the remote node (Step
1) to be hashed with a secret Integrity key stored
there (Step 2). The integrity key is different from the
other secret keys stored in the node and used for
authentication and confidentiality. The digest of that
hashing of the secret key and challenge becomes
the Intermediate Integrity Key. The same
Intermediate Integrity Key is already stored in
software on the host. It was previously created in
the factory using the same challenge number which
was hashed in the factory with the same secret key
securely stored on the tester in the factory using the
same hashing algorithm. The integrity key once
created in the factory was made available to be
compiled into the host’s software along with the
corresponding challenge number from which it was
created.
Moving back to the Node, the original message gets
hashed with the intermediate key on the Node to create a Message Authentication Code (MAC), which is called the Message MAC (Step 4). But first the
message needs to be prepared for that step by being sized correctly. That is done either by digesting the message or padding it, depending on the size of
the original message (Step 3). 32 bytes is the size of the input to the SHA 256 hashing step. The Message MAC is then added to the original message and
that combined code is encrypted and sent to the host (Step 5).
When the host receives the encrypted code it decrypts it to retrieve the original message and the Message MAC (Step 6). The host will soon use the
Decrypted Message MAC to check for authenticity. It does that by hashing the intermediate key stored on the host with the decrypted message, which is
prepared for hashing as done on the other side (step 7). That hash creates the Host Message MAC which is then compared with the Decrypted Message
MAC (step 8). If they match then the data integrity of the message is verified.
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50.
Node Authentication Using Symmetric Intermediate Keys
To provide node authentication in a platform
where it is not possible or desirable to securely
store a secret key on the host, a method called
fixed challenge-response using an intermediate
key is recommended. A fixed challenge is a
number that has previously been loaded into the
host’s software. To start the process that
challenge number is sent to the remote node
(Step 1) to be hashed with a secret
authentication key stored there (Step 2). That
key is different from the other secret keys stored
on the ATSHA204 that are used for
confidentiality and data integrity. The digest of
that hashing process is the intermediate
authentication key. That same challenge
number was previously hashed in the factory
with the same secret key securely stored there
(on the tester) and the same hashing algorithm
to create that very same intermediate key. That
intermediate key was then compiled into the
host’s software along with the challenge.
The host then sends a random number to the
node (Step 3). The host hashes its intermediate
key with the random number to create a digest
called the Node Response (Step 4), which is
then sent to the host. On the host, the same
random number is hashed with the intermediate
key stored on the host (Step 5) to create a
digest called the Host Response. The host’
response and node responses are compared,
and if those digests match then the authenticity
of the node is verified (Step 6).
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51.
Confidentiality using ECDH Key Agreement
(with ATECC508A)
Confidentiality is making sure that the message cannot be seen by an unintended party. The method used is encryption and decryption
based upon a selected algorithm, which in this
example is Advanced Encryption System (AES).
To perform encryption and decryption, both sides
need the same encryption/decryption key which
is input to the algorithm on each side. The trick
is to produce the key in each side in a way that
does not allow anyone else to obtain it. An
excellent way to do that is to create a new key
for each communication session by sending
information that only the intended parties can
use to create the keys. The fact that a new key
is created for each session increases security
greatly. This method is not surprisingly called
session key exchange. This is what we will now
describe.
The example here is ECDH key exchange which
stands for Elliptic Curve Diffie-Helman. The
ECDH mathematics called point-multiply
(depicted by the dot in the diagram) works such
that the private key of side A point multiplied by
the public key of side B is exactly equal to the
private key of side B point-multiplied by the
public key of side A. The key point is that
knowing the public key of either side does not
allow anyone else other than the intended
parties to obtain the shared session key. (The
mathematical magic of elliptic curve pointmultiply is explained elsewhere.) Once the encrypting side (which can be either side but is defined as side A in this example, get the session key that can be
used by the microprocessor to encrypt the message using AES (in this example. The encrypted message is then sent to the other side (Side B) which also
now has the same session key due to the result of the ECDH calculation don on Side B’s private key and Side A’s public key. The micro then uses the
session key to decrypt the encrypted message. That completes the key agreement and encryption/decryption process.
To obtain data integrity an alternative model of AES can be employed such as AES-CCM or AES-GCM. To obtain authenticity the ECDSA operation in the
ATECC508A can be run. Therefore all three of the pillars of security are possible using the ATECC508A, namely Confidentiality, Integrity, and Authentication
(which ironically is sometimes referred to as “CIA”).
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52.
ATECC508A Provides Confidentiality, Integrity, and Authenticity.
The ATECC508A stores keys, secrets, and
certificates on-chip in protected hardware,
which is the strongest form of storage. The
ATECC508A provides ECDSA (P256 curve) to
implement authentication via the sign-verify
process.
The device also runs ECDH (Elliptic Curve
Diffie-Helman) Key Agreement capability to
implement confidentiality (via
encryption/decryption). The ATECC508A is a
perfect companion for microprocessors
running encryption algorithms such as AES,
because of the built in ECDH key agreement
functionality, which easily provides the
microprocessor with the encryption/decryption
keys on each side of the process using simple
command calls.
The ATECC508A can very simply implement
secure boot using the ECDSA validation
process (the yellow blocks in the diagram)
ensuring that only the correct (i.e. validated)
code is loaded at boot time.
In systems where ECDH key agreement is
used with microprocessors running AES, data
Integrity can be easily provided using various
mechanisms such as AES-CCM and AESGCM.
Therefore, all three of the pillars of security are supported by the ATECC508A; namely, confidentiality, integrity, and authentication (sometimes called
“CIA”), making this a very elegant and robust security solution.
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53. Security and the IoT
Security matters in the IoT because users must
trust that the nodes are who they say are (i.e.
are authentic). Additionally, confidentiality of
the data is important to keep unauthorized third
parties from getting the data and misusing it.
Also, without data integrity mechanisms there is
no way to ensure that data have not been
tampered with or corrupted. All three of these
matter...A lot. Without security the IoT cannot
be trusted. Fortunately, the ATECC508A addresses all of the pillars of security. Crypto engines like the ATECC508 with secure
hardware-based key storage will help catalyze the growth of the IoT. As you can see in the charts, the growth of the IoT will be
astonishing, but without real security the IoT will remain simply a toy. Clearly, security matters in the IoT market…and
everywhere else.
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54.
The Mathematical Magic of ECDH Key Agreement
What if you and I want to exchange encrypted messages? Encryption is essentially scrambling a message so only the intended reader can see it after
they unscramble it. By definition, scrambling and unscrambling are inverse (i.e. reversible) processes. Doing and undoing mathematical operations in
a secret way, which outside parties cannot understand or see, is the basis of encryption/decryption. Julius Caesar used encryption to communicate
privately. The act of shifting the alphabet by a specific number of places is still called the Caesar cipher. Note that the number of places is kept secret
and acts as the key.
A modern-day encryption key is a number that is used by an encryption algorithm, such as AES (Advanced Encryption Standard) and others, to
encode a message so no one other than the intended reader can see it. Only the intended parties are supposed to have the secret key. The
interaction between a key and the algorithm is of fundamental importance in cryptography of all types. That interaction is where the magic happens.
An algorithm is simply the formula that tells the processor the exact, step-by-step mathematical functions to perform and the order of those functions.
The algorithm is where the magical mathematical spells are kept, but those are not kept secret in modern practice. The key is used with the algorithm
to create secrecy.
For example, the magic formula of the AES algorithm is a substitution-permutation network process, meaning that AES uses a series of mathematical
operations done upon the message to be encrypted and the cryptographic key (crypto people call the unencrypted message “plaintext“). How that
works is that the output of one round of calculations done on the plaintext is substituted by another block of bits and then the output of that is changed
(i.e. permutated) by another block of bits and then it happens over and over, again and again. This round-after-round of operations changes the
coded text in a very confused manor, which is the whole idea. Decryption is exactly as it
sounds, simply reversing the entire process.
That description, although in actual fact very cursory, is probably TMI here, but the point is that
highly sophisticated mathematical cryptographic algorithms that have been tested and proven to
be difficult to attack are available to everyone. If a secret key is kept secret, the message
processed with that algorithm will be secret from unintended parties. This is called Kerckhoffs’
principle after it author Auguste Kerchoffs who was a Dutch professor, linguist, and
cryptographer in the 19th century. His principle could be paraphrased as, “The key to encryption
is the key.” This powerful concept is the heart of modern
cryptography. What it says is that you need both the
mathematical magic and secret keys for strong
cryptography.
Another way to look at is that the enemy can know the
formula, but it does him or her no good unless they know the
secret key. That is, by the way, why it is so darn important to
keep the secret key secret. Getting the key is what many attackers try to do by using a wide variety of innovative
attacks that typically take advantage of software bugs. So, the best way to keep the secret is to store the key in
secure hardware that can protect if from attacks. Software storage of keys is just not as strong as hardware
storage. Bugs are endemic, no matter how hard the coders try to eliminate them. Hardware key storage trumping
software is another fundamental point worth remembering. So now that we have a good algorithm (e.g. AES) and
a secret key we can start encrypting to gain confidentiality.
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The Mathematical Magic of ECDH Key Agreement
(Continued)
Key Agreement
In order for encryption on the sender’s side and decryption on the receiver’s side, both sides must agree to have the same key. That agreement can
happen in advance, but that is not practical in many situations. As a result, there needs to be a way to exchange the key during the session where the
encrypted message is to be sent. Another powerful cryptographic algorithm will be used to do just that.
There is a process called ECDH key agreement, which is a way to send the secret key without either of the sides actually having to meet each other.
ECDH uses a different type of algorithm from AES that is called “EC” to send the secret key from one side to the other. EC stands for elliptic curve,
which literally refers to a curve described by an elliptic equation.
A certain set of elliptic curves (defined by the constants in the equation) have the property that given two points on the curve (P and Q) there is a third
point, P+Q, on the curve that displays the properties of commutivity, associativity, identity, and inverses when applying elliptic curve point
multiplication. Point-multiplication is the operation of successively adding a point along an elliptic curve to itself repeatedly. Just for fun the shape of
such an elliptic curve is shown in the diagram above.
The thing that makes this all work is that EC point-multiplication is doable, but the inverse operation is not doable. Cryptographers call this a one-way
or trap door function. (Trap doors go only one way, see?) In regular math, with simple algebra if you know the values of A and A times B you can find
the value of B very easily. With Elliptic curve point-multiply if you know A and A point-multiplied by B you cannot figure out what B is. That is the
magic.
That irreversibility and the fact that A point-multiplied by B is equal to B point-multiplied by A (i.e. commutative) are what makes this a superb
encryption algorithm, especially for use in key exchange.
To best explain key agreement with ECDH, let’s say that everyone agrees in advance on a number called G, which is a constant point on the Elliptical
curve. Now we will do some point-multiply math. Let’s call the sender’s private key PrivKeySend. (Note that each party can be a sender or receiver,
but for this purpose we will name one the sender and the other the receiver just to be different from using the typical Alice and Bob nomenclature
used by most crpyto books.) Each private key has a mathematically related and unique public key that is calculated using the elliptic curve
equation. Uniqueness is another reason why elliptic curves are used. If we point-multiply the number G by PrivKeySend we get PubKeySend. Let’s
do the same thing for the receiver who has a different private key called PrivKeyReceive and point-multiply that private key by the same number G to
get the receiver’s public key called PubKeyReceive. The sender and receiver can then exchange their public keys with each other on any network
since the public keys do not need to be kept secret. Even an unsecured email is fine.
Now, the sender and receiver can make computations using their respective private keys (which they are securely hiding and will never share) and
the public key from the other side. Here is where the commutative law of point-multiply will work its magic.
The sender point-multiplies the public key from the other side by his or her stored private key.
This is equates to:
PubKeyReceive point-multiplied by PrivKeySend which = G point-multiplied by PrivKeyReceive point-multiplied by PrivKeySend
The receiver does the same thing using his or her private key and the public key just received.
This equates to:
PubKeySend point-multiplied by PrivKeyReceive = G point-multiplied by PrivKeySend point-multiplied by PrivKeyReceive.
Because point-multiply is commutative these equations have the same value!
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The Mathematical Magic of ECDH Key Agreement
(Continued)
And, the rabbit comes out of the hat: The sender and receiver now have the exact same value, which
can now be used as the new encryption key for AES in their possession. No one else can get that
value. That is because someone else would need to have one of the private keys, which they cannot
get.
This calculated value can now be used by the AES algorithm to encrypt and decrypt messages.
Pretty cool, isn’t it?
Below is a link to a wonderful video explaining the modular mathematics and discrete logarithm
problem that creates the one-way, trapdoor function used in Diffie-Hellman key exchange. (Oh
yeah, the “DH” in ECDH stands for Diffie-Hellman who were two of the inventors of this process.)
http://www.youtube.com/watch?v=3QnD2c4Xovk
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55.
Using diversified keys to increase security
An excellent way to increase security in a symmetric operation is to use something called diversified keys. This is also called a Key Derivation
Function (or KDF). What that means is that the key that is in the host, called the root key, is not shared as such with the clients. Instead each client gets a
derivative of that root key based upon a unique number assigned to that particular client, such as its serial number. That serial number is hashed with the
root key in the factory and stored in the client device and it is known as the “diversified key”. It is called diversified since each client’s key will be different
from that is other clients (i.e. they are diverse).
To authenticate with a diversified key, the host must be able to create the diversified key just like it was created in the factory. Therefore, it will need the
serial number from the client. So, the client sends the serial
number to the host MCU and the host hashes the serial
number with the stored secret root key. That hash value
(digest) should then be the same as the client’s diversified
key. The next step is to use a random number challengeresponse operation to verify that the keys are the same, and
thus that the client is real. To do so, the host sends a
random number challenge to the client which then hashes
that number with the stored diversified key (that was
inserted in the factory). The digest of the key and challenge
is the Response, and that is sent to the host. The host
hashes the same random number with the diversified key it
created from the client’s serial number and stored root key.
It compares that digest with the response to see if they
match. If they do then the client is considered as being real.
Benefits

All clients will have a different key so the loss of one
does not affect any others


Simple operation to improve security substantially
Users can use this technique to easily create client
blacklists
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56.
Innovations that make Atmel secure key
storage devices robust.
Looking at the red border in the diagram you can see a tamperhardened hardware boundary.
This boundary contains defense mechanisms such as shields,
regulators, clock generators, and other counter-measures so
attackers cannot see what is inside. You can see in the lower picture
the structure of the serpentine metallic shield that covers the entire
chip. This shield is integral to the active circuitry so even if the device
is deprocessed, nothing will be revealed. So, attackers cannot see
what is inside, and they cannot attack what they cannot see.
All the devices employ the same basic architecture of secure
EEPROM for keys & data with the crypto engine standing between
the interface and memory.
A one-way counter tracks how many times the device authenticates.
Even when the power is turned off, the count remains the same. All
the devices include internal high quality hardware Random Number
Generator, which is required for every cryptographic protocol. In
addition, all the products include a guaranteed unique serial number
for identification and key diversification.
The memories are all internally encrypted, and an array of tamper-detection schemes is in force. JTAG is not used, and there are no debug, probe, or test
points. Such design methodologies add up to a ultra-strong defense against micro probing, timing, emissions and other types of attacks.
Simply put: “It is not possible to achieve this level of security with software alone.”
Benefits


Multiple levels of hardware security

Guards against numerous styles of attacks
Cannot achieve this level of security with
software alone!
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57. Consumption Tracking
The consumption tracking feature on CryptoAuthentication devices offers an easy way to control various use cases such as the number of times a
product can be used, which can help to ensure the quality of products and systems. By counting the number of uses designers can ensure that the
accessory such as a printer ink tank, for example, will not operate when the ink is too low for a high quality image.
Another application of the counter is called “pairing restriction”
which is a one-to-one match between one host and one client
being allowed, which adds more security benefits. Once a
client is used with a specific host it can then not be used on
another host.
CryptoAuthentication devices can also attach the counter to
cryptographic keys. This is done be using the counter as an
input to a hash function with a stored key to create a MAC.
Because the counter only increments in one direction (i.e.
monotonic) the MAC will always be different since the counter
number input to the hash will not be repeated. Using the ink
tank example again, that means that an ink tank cannot be
refilled and used again because it cannot be re-authenticated
due to the MAC being different because of the incrementing
counter.
ATECC508A adds capability to count to 2 Million, and it can
use all 15 keys
In addition, the counters can be used to perform traditional
cryptographic audit functions.
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58. Secure Personalization
To perform the specific authentication task required by a target
application using CryptoAuthentication™ devices, the devices must
first be programmed. This programming process is called
“personalization” and entails configuring the device with the desired
firmware protection profile, which includes secrets such as secret
keys. Any way of doing so must protect the keys at every step.
There is a range of ways to personalize the device:
1) Using a socket developed in-house by the customer and issuing commands to every memory location in the device. This is not
well suited for volume production
2) Use Atmel Crypto Evaluation Studio (ACES) software tool to issue commands to an AT88CK101 development kit that houses
the device in a socket.
3) Use the Atmel AT888CK9000 Secure Personalization Kit. This kit programs up to 5 devices at a time using the ACES tool.
4) Use an approved third-party programmer from System General or Xeltek.
5) Use a secure personalization service from a trained and authorized Atmel partner, such as Avnet, Arrow, and EBV.
6) Use Atmel’s “Secure Personalization Services”. Atmel provides the full personalization process that loads the customer’s
secrets into the volume production devices in a highly secure way. What “secure way” means is that the customer’s secrets
are never exposed at any point in the process, even to Atmel. Secure algorithms, processes, and hardware security modules
are employed to preserve the secrets.
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59.
Secure Personalization Services
Atmel’s Secure Personalization Service is designed to transfer the secrets
from the customer site to the CryptoAuthentication device without the
secrets ever being in the clear, or viewable by party other than the customer.
Even Atmel is not able to see the secrets.
Once the configuration of the device has been designed, the customer
receives a “Secrets Exchange Package” from Atmel which includes a
Personalization Utility program that encrypts the customer’s secrets located
in an .XML file. This utility may also perform some formatting and logic
testing on the customer’s data. There are also a Configuration XML file
representing the memory configuration of the device (not including the
secrets), and RSA keys that will be used to encrypt the customer’s .XML file.
These keys are generated on Hardware Security Modules (HSMs) located at the Atmel contractor sites where the final IC package tests
are performed. (There can be multiple keys depending on the number of locations where the ICs will be personalized.)
The items enumerated above are used to transfer the customer’s secrets between three entities:
1) The Customer’s site
2) The Atmel Hardware Security Module (HSM) at Atmel’s production site, and
3) The Atmel CryptoAuthentication™ device itself, on the tester at Atmel’s production site.
The concept behind this process is very simple. The customer makes the secret and transfers it to Atmel in encrypted format to be
stored in the HSM, which is a secure module that not even Atmel can access. When the secrets are to be loaded into the
CryptoAuthentication device on the tester, only then are the secrets decrypted inside the HSM and immediately re-encrypted to be
transferred to the device. Only when they are securely inside the CryptoAuthentication device (which itself is protected hardware (by
definition)) are the secrets decrypted and loaded into the assigned memory slots. The secrets are never in the clear.
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60. Additional Configuration Options
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61. Atmel CryptoAuthentication ™ Devices
The ATSHA204A is ideal for cost sensitive applications given its low price. It is perfect for applications that store the same
secret in the host and client. It supports the SHA256 cryptography algorithm.
The ATECC108A/508A are advantageous for systems with components from different manufacturers because secrets can be
easily locked. Also, the devices are optimal for ECDSA and X.509 digital certificate procedures, because those capabilities are
built right in. Both are supersets of the ATSHA204A, so they perform all the same symmetric functions. The devices support
both SHA256 and ECC. The ATECC508A additionally supports
ECDH key agreement making it ideal for network node and IoT
applications using encryption methods such as AES.
The ATAES132A is a secure drop-in for serial 32K EEPROMs. It is a
fitting solution for securing up to 4K bytes of data for fingerprints,
calibration data, firmware blocks, biometrics and other things. The
device supports the AES128 cryptography algorithm.
These are just a few of the high points. There are many other points
of differentiation as well, which you can see in more detail in the
datasheets




Watch Atmel's webinar: Why Investing in Security is Important in Embedded Systems
View Atmel security videos
ATSHA204 datasheet
View More Atmel Security Videos
Benefits





Price sensitive option (ATSHA204A)
Symmetric options (ATSHA204A & ATECC108A/508A)
Asymmetric authentication (ATECC508A) with ECDSA and ECDH
built-in
Asymmetric authentication (ATECC108A) with ECDSA built-in
Add security with a drop in device to standard EEPROM sockets
(ATAES132A)
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62. Competitive Advantages
Lower cost, higher security, better usability
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63. AES encryption in the real world
AES is a great algorithm in wide use. It has been carefully studied by legions of cryptanalysts, so it’s often
assumed that a system which includes AES is secure. But that assumption isn’t always true. Let’s
explore three problem areas.
Like all cryptographic systems and algorithms, AES depends on a key. If an attacker can get the key, he
or she can impersonate the authentic party, decrypt all the network messages and generally eliminate
every aspect of the system security. The key to security is the securing the key. The problem, however,
is that very few systems in fact provide a truly secure place to store keys that is truly isolated from attack.
(Unless they use protected hardware key storage, of course.)
With the increasingly connected systems, software bugs can easily find keys that you thought you had
carefully protected. The Heartbleed bug is a perfect example.
Like all cryptographic algorithms, there are many variations to the way in which AES can be use, which
contributed to the fact that a lot of systems have been cracked because an improper mode, protocol or procedure was used. Cryptography must be done
correctly to be secure. That is obvious but not always easy. The picture here shows what happens when it is not done right.
The last point is a bit trickier. When encrypting something with AES, most modes require an Initialization Vector (IV). An
IV should never be repeated, and in some modes it must be random. There are two problems with a repeated IV: 1) If
the attacker could discover the plain text of the first message, he could determine the contents of the second; and 2), if
the same message is sent with the same IV, the ciphertext will be the same both times, which is vital information that can
be used by attackers to break the encryption.
The big point here is that it is hard to generate a random number. The universe may trend towards entropy but it is
filled with patterns along the way, so randomness is not exactly natural. It has to be captured carefully. One famous
random number generator used the hash of an image of lava lamps, and for some years an online site (“Lavarand”) was
supported by Silicon Graphics to provide online numbers.
Assuming you don’t have lava lamps and a camera in your system, you might be tempted to use ‘random’ keystrokes,
noise on a signal wire, the current time to the ms, or some similar thing. Problem is, while the resulting numbers appear
to be random there are often a limited number of choices. Given how fast modern computers execute, an attacker can
try literally millions of possibilities in a few seconds and guess your random number!
Many designers rely on dedicated hardware cryptographic devices to help resolve this issue. Generally speaking, they
offer solutions to the three points mentioned above:
1) Strong protection for cryptographic keys that is not subject to bugs, malware or other aggressive attacks
2) Proper use of modes and protocols for the operations performed within the devices
3) High quality random number generators that rely on random physical phenomena and which are rigorously tested
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64.
Message Authentication Example
CryptoAuthentication crypto element devices can be used to authenticate a message by
creating a simple Message Authentication Code (MAC) and appending that MAC to the
message packet. A MAC is a very fundamental cryptographic function. The basic definition
of a MAC is the result of a hash (compression) of a key and message. In this example the
message is the start time, end, time, and the authorized action. That message is first
hashed by the host to put it into the right size to be input to another hash with the key to
create the MAC. Now that the MAC is created by the CryptoAuthentication device it is
appended to the original (un-hashed) message packet. The packet with the MAC is sent to
the other side where it will be validated.
The core of this application is that the execution of the authorized action will depend upon
the current time being within the time range specified (i.e. between the start and end times).
The original message, which is the action to be authorized, is input to a hash function in the
microprocessor just like was done on the other side, to be sized correctly to then be input to
the CryptoAuthentication device.
The CryptoAuthentication device hashes the hashed (compressed) message with the
key stored there to make the MAC. The MAC on that side is compared to the MAC
that was sent over from the other side. If the MAC s match, then the messages must
be identical, and that proves that they were not tampered with. Now that you know the
messages are authentic, the current time can be checked with the range sent over in
the original message to see if it is in the specified range. If it is then the authorized
action can be executed.
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65.
Intrusion Detection Feature (ATECC108A & ATECC508A)
The ATECC108A and ATECC508A devices have the ability to disable authentication of chosen keys if an intrusion is detected. Automatic disabling of
authorization keys in the case of a physical intrusion helps businesses and consumers avoid or mitigate losses.
When the ATECC108A or ATECC508A is used in the Intrusion mode, it immediately and automatically stops unauthorized access to the keys in the device.
Intrusions can take the form of opening or closing a door without prior authorization, proximity alerts, automobile break-ins, or even dead-man switches in the
case of unauthorized machine operations.
If the use of a system feature is tied to a key in the ATECC108A
device, by the automatic disabling a key when an intrusion is
detected, the use of the key and associated feature will
automatically be disabled as well since it can no longer be
authorized. The intrusion detection solution is deployed in two
parts:
1.
Perform a one-time configuration of the intrusion detect
mode on the ATECC108A, and define which keys should
be disabled when an intrusion is detected.
2.
Arm the device to detect intrusion and disable chosen
keys.
Note: The intrusion detection is only available for the versions of
the devices supporting Single-Wire Interface (“SWI”)
communication since it co-opts the SCL pin used in 2-wire
communication. Devices configured for SWI, the SCL pin can be
configured as a GPIO pin (an input in the case of intrusion trigger).
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66.
Feature Summary of ATMEL ECC CryptoAuthentication devices (ATECC108A and ATECC508A)
All of these are optional
Host Mode


Same device can both generate and verify P256 ECDSA signature
Verify takes ~25ms with 500MHz Cortex A5, <50ms ATECC108
Store public key validation



Additional NV per public keys, stores key validation status
Subsequent authentication to same node requires just a single sign/verify
Can support X.509 format signatures via on-board SHA command
Fully Compatible with SHA256-based ATSHA204

Full suite of symmetric authentication/validation
SHA256 hash command

~9ms per 64 byte block
Compressed certificates





Store information necessary to re-create full x.509 certificate in only 72 bytes
Can store 8 on-chip, others off-chip
Use standard certificate validation software
Single (Limited) Use Keys, (if so configured)
Once keys have been used the desired number of times, they are no longer usable
Individual slot locking

Once locked, a slot can no longer be changed. Store model information, network address, etc.
Random nonce requirement





Prevents replay attacks by requiring that the cryptographic transaction includes a random number
Key authorization
Requires knowledge of appropriate key to enable use of target key on a per-use basis. The authorization status is not
stored in NVM.
Either symmetric or asymmetric validation
One use model is password authorization
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67.
Feature Summary of ATMEL ECC CryptoAuthentication devices (ATECC108A and ATECC508A)
All of these are optional
Tamper (intrusion) input pin


Connect to switches on case, metal shields over device, etc. to detect physical ‘attack’ on the system
Typically useful where battery power is always present
Authenticated output


Driven to programmable default level on power-up, then to opposite state after validation (symmetric or asymmetric)
Enable portions of system, status indication, etc.
GPIO


2.0 x 3.0 x 0.6mm, 8-lead UDFN is preferred
Totem-pole output capable of driving dual-color LED. Retains state during sleep
Selectable input thresholds

Useful if chip supply is higher than that of micro (e.g. 1.8V)
CRC-16 protected IO


Results can be re-transmitted without re-computation (or ignored)
CRC-16 source code software in library on website
Written by Atmel during manufacture
•
Cannot be changed in the field
24 bit Fixed for customer Devices
•
•
Included in all symmetric calculations and some asymmetric calcs
Sold only to customer or authorized third parties
8 bit unique ID
•
Guaranteed to be unique for all CryptoAuthentication devices
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68. Atmel CryptoAuthentication ™ Devices: ATECC108A
The ATECC108A supports full 256-bit Elliptic Curve Cryptography. A key feature is there is not any need for secure
storage in the host. The ATECC108A includes an EEPROM array for storage of up to 16 keys, miscellaneous
read/write, read-only or secret data, consumption logging, and security configurations. Access to memory can be
restricted in a variety of ways and then the configuration can be locked to prevent changes.
The ATECC108A features defense mechanisms to prevent physical attacks on the device or logical attacks on the
data transmitted between the device and the system. Hardware restrictions on the keys generation or use provide
further defenses. Access to the device is made through a standard I2C Interface at speeds of up to 1Mb/. It also
supports a Single-Wire Interface (SWI), which can reduce the number of GPIOs required on the system MCU.
Multiple ATECC108A devices can share the same bus, which saves processor GPIO usage in systems with multiple clients.
Using the ATECC108A’s cryptographic protocols, a host system or remote server can verify a signature to prove that the serial number is authentic. The
ATECC108A can generate high-quality FIPS random numbers for any purpose including ensuring that that replay attacks (i.e. re-transmitting a previously
successful transaction) always fail. System integration is easy due to a wide supply voltage range (of 2.0V – 5.5V) and an ultra-low sleep current (of
<150nA).
Benefits



Easy way to run Elliptic Curve Digital Signature Algorithm (ECDSA) Sign-Verify operations
Authentication without the need for secure storage in the host
No requirement for high speed computing in client devices
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69. Atmel CryptoAuthentication ™ Devices: ATSHA204A
The ATSHA204 has been architected to provide flexible user-configured security to enable a wide range of authentication
models, and is easy and timely to design in with no crypto expertise required. The ATSHA204A supports the SHA256
standard and is the most cost effective solution in the portfolio today. The first CryptoAuthentication product to integrate the
SHA-256 hash algorithm with a 4.5Kb EEPROM, the ATSHA204A provides robust hardware authentication and secure
key/data storage. Features such as small outline plastic package and a single-wire interface make the Atmel ATSHA204
ideal for handheld electronic systems or any space-constrained embedded system.
Implementing host-side security to provide a full system solution is now easier than ever. The devices include a client and
host security capability that offloads key storage and the execution algorithms from the microcontroller, significantly
reducing both system cost and complexity. CryptoAuthentication incorporates the latest security features developed from a long history of security IC design
expertise. The devices have full metal shields over the entire internal circuitry, so that if an attacker cuts or shorts any trace in the shield, the device stops
functioning. Additional security features include internal clocks and voltage generation, encrypted memories, tamper detection and fully secure production
test methods.
Features include:












Superior SHA-256 NIST-approved algorithm
Secure authentication and key exchange
Integrated capability for Host and Client
Superior SHA-256 Hash algorithm with Message Authentication Code (MAC) and Hash-Based Message Authentication Code (HMAC) options
Best-in-class, 256-bit key length; storage for up to 16 keys
Guaranteed unique 72-bit serial number
4.5Kb EEPROM for keys and data
512 bit OTP (One Time Programmable) bits for fixed information
2.0V to 5.5V supply, and 1.8V to 5.5V communications voltage ranges, <150nA sleep current
8-SOIC, 8- TSSOP, 3- SOT23, 8-UDFN, and 3-lead Contact packages
Single-wire and I2C interface
Secure personalization
Benefits




Cost effective symmetric authentication solution
Fast authentication
No need to become a crypto expert
Easy key management
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70. Atmel CryptoAuthentication ™ Devices: ATAES132A
The ATAES132A is a very fast, high-security, serial 32 K EEPROM that enables authentication and confidential
nonvolatile data storage. It is a direct drop-in for industry standard serial EEPROMS, and supports the AES
cryptography standard. Access restrictions for the 16 user zones are independently configured and any key can be
used with any zone. Keys can also be used for standalone authentication. Such flexibility permits the ATAES132 to
be used in a wide range of applications. The AES-128 cryptographic engine operates in AES-CCM mode to provide
authentication, stored data encryption/decryption, and Message Authentication Codes (MACs). Data
encryption/decryption can be performed for internally stored data or for small external data packets, depending upon
the configuration. Data encrypted by one ATAES132 device can be decrypted by another, and vice versa. Extended
security functions are accessed by sending command packets to the ATAES132 using standard Write instructions and reading responses using standard
Read instructions. The device incorporates multiple physical security mechanisms to prevent release of the internally stored secrets. Secure personalization
facilitates 3rd-party manufacturing. The device provides sixteen high-endurance monotonic EEPROM Counters. The Configuration Memory registers control
access to the User Memory, as well as the restrictions on Key and Counter functionality. The User Memory can be accessed directly with standard SPI or
I2C commands. The device’s Secure Serial EEPROM architecture and packages compatible with standard SPI and I2C EEPROM footprints allow insertion
into many existing Serial EEPROM applications.
Features include:
 32Kb Standard Serial EEPROM User Memory (16 User Zones of 2Kb)
 AES Algorithm with 128-bit Keys; AES-CCM for Authentication
 MAC for Cryptographic Operations
 Secure Storage for 16 128 bit Keys
 Encrypted User Memory Read and Write
 FIPS Random Number Generator (RNG)
 16 High-Endurance Monotonic EEPROM Counters
 User Zone Access Rights Independently Configured
 Authentication Prior to Zone Access
 Read/Write, Encrypted, or Read-only User Zone Options
 SPI and I2C Interface Options
 2.5V to 5.5V Supply, <250nA Sleep
 Serial EEPROM Compatible Pinout (SOIC, SOP, or UDFN)
Benefits
 Drops into existing sockets to upgrade for high security
 Authentication plus encryption in a single protocol
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71. Atmel CryptoAuthentication ™ Devices: ATECC508A
The ATECC508A is the first crypto device to integrate ECDH (Elliptic Curve Diffie–Hellman) key agreement,
which makes it easy to add confidentiality (encryption/decryption) to digital systems including Internet of Things
(IoT) nodes used in home automation, industrial networking, accessory and consumable authentication,
medical, mobile and other applications. In addition to ECDH the ATECC508A also has ECDSA (Elliptic Curve
Digital Signature Algorithm) sign-verify capabilities built right in to provide highly secure asymmetric
authentication. The combination of ECDH and ECDSA in the ATECC508A makes the device an ideal way to
provide all three pillars of security—namely confidentiality, data integrity, and authentication—when used with
MCU or MPUs running encryption/ decryption algorithms (such as AES) in software. Similar to all Atmel
CryptoAuthentication products, the new ATECC508A employs ultra-secure hardware-based cryptographic key
storage and cryptographic countermeasures which are more secure than software-based key storage. This
next-generation CryptoAuthentication device is compatible with any microprocessor (MPU) or microcontroller (MCU) including Atmel® | SMART and
Atmel AVR® MCUs or MPUs. As with all CryptoAuthentication devices, the ATECCC508A delivers extremely low-power consumption, requires only
a single GPIO over a wide voltage range, and has a tiny form factor, making it ideal for a variety of applications including those that require longer
battery life and flexible form factors.
Benefits



Easy way to run Elliptic Curve Digital Signature Algorithm (ECDSA) and Elliptic Curve Diffie-Hellman (ECDH) Key Agreement
Authentication without the need for secure storage in the host
No requirement for high speed computing in client devices
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72.
ATECC508A Datasheet
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73. Atmel CryptoAuthentication ™ ECC Device Comparison
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74.
CryptoAuthentication Device Selector Guide
ATSHA204A
Status
Description
Full Production
Secure authentication and
validation device
Data Sheet Status
Authentication
Crypto Algorithms
ATECC108A
Full Production
Full Production
High speed PKI crypto engine with secure key storage.
FIPS186-3 Elliptic Curve Digital Signature Algorithm (ECDSA) for ECC
Sign-Verify
ATAES132A
Full Production
High-security, Serial EEPROM providing authentication
and confidential nonvolatile data storage.
Runs FIPS SP800-56A
Elliptic Curve DiffieHellman Algorithm
ECDH
Function(s)
ATECC508A
Authentication
Authentication, and key
exchange for
confidentiality and data
integrity (when used with
AES)
Authentication
Public
NDA
SHA , HMAC
(Symmetric)
SHA, HMAC, (Symmetric),
SHA256
ECC (Asymmetric)
SHA256, ECCP256
SHA256 ,ECC-P256,ECCB283,ECC-K283
SHA=256; ECC=P256
SHA=256; ECC=P256; =K283,
=B283
Encryption / Authentication
Public
AES-CCM (Mutual) (Symmetric)
AES128
Key Length
256
Secure boot
SHA
SHA/ECC
-
Key Exchange
SHA
SHA
AES-CCM
-
SHA, ECC
AES
Key Creation
SHA / Random
SHA / Random
Random
Command
Authorization
-
Key Authorization
Encrypted Read/Write
SHA / XOR
-
SHA / XOR
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AEC-CCM
AES-CCM
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75.
CryptoAuthentication Device Selector Guide
ATSHA204A
Commands
ATEC508A
ATECC108A
ATAES132A
13
18
26
3 mA
16 mA
26 mA
Sleep
< 150nA
< 150nA
<250nA
Vcc
2.0 – 5.5V
2.0 – 5.5V
2.5V to 5.5V
1.8V to 5.5V
1.8V to 5.5V
10 Kb
32K b(User); 2Kb(Keys)
Power (max.)
Communications
Voltage
1.8V to 5.5V
EEPROM size
4.5Kb
I/O Interface
I2C, Single Wire
Key Offload &
Reload
-
Packages
High-speed SPI with one GPIO Pin,
1MHz I2C
-
UDFN8, SOIC8,
UDFN8, SOIC8, 3-Contact (RBH)
SOT23-3, 3-Contact (RBH)
I2C, SPI
Yes
UDFN8, SOIC8
Limited Use Keys
9
9
16
Secure Count Max
1K
1K
2M x 16
Authentication
Counter
Yes
Factory Unique ID
72 bits
Yes
72 bits
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128 bits
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76.
CryptoAuthentication Device Selector Guide
ATECC508A
ATSHA204A
Special
Features
Target Apps
 Turnkey authentication,
validation,
key derivation, and
password checking
 Lowest cost Atmel
Encryption / Authentication
Device
 Cost sensitive apps.
 Apps where all components
are from same OEM.
ATECC108A





Only host has to store public key
Slot locking in field
Programmable random Nonce
1.75k bit slot for storage
512 OTP Bits for Fixed Information or
Consumption Logging
 Intrusion Protection
 Full compatibility with ATSHA204
 Apps where host hardware changes
are difficult.
 Apps with many partners or complex
ecosystem.
 Network Node authentication / IoT
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ATAES132A
 Full HW & SW compatibility with serial
EEPROMs,
 16 counters
 Anti-clone circuitry
 Mutual authentication w. mutual
random Nonce
 On-off chip key transfer
 On-board encryption/decryption of
external data
 I2C mode has "Auth Out" pin to show
valid authentication
 Apps needing full software
compatibility with serial EEPROM or
SPI
 Apps that need to secure up to 4Kbytes
of data for fingerprints, calibration
data, firmware blocks, etc.
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CryptoAuthentication Device Selector Guide
ATSHA204A
ATECC508A
ATECC108A
ATAES132A
Same device for both host and client sides
Can be securely personalized
Enforces random Nonce
Secure test
Hardware and PRNG components
Internal clock generation
Random Number Generator (RNG)
Other
Features
Cost effective key-only and secrets-only storage
Internally encrypted memories
Voltage tamper resistance
Common root of trust
Active Shield
Randomized math operations
No probe or test points
Data independent crypto execution
1: All devices include additional configuration memory.
Notes
2: Monotonic counters can operate independently or be connected to cryptographic keys.
3: Specifications are subject to change
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78.
Atmel CryptoAuthentication Device Ordering Guide: ATECC108A
Atmel Ordering Code
Package Type
Interface
Configuration
ATECC108A-SSHCZ-T
8-lead SOIC , Tape and Reel; 8S1, 8-lead (0.150” Wide Body), Plastic
Gull Wing Small Outline (JEDEC SOIC) ; Green, (Pb free, halogen free,
ROHS) -40 to 85 degrees C
Single-Wire
ATECC108A-SSHCZ-B
8-lead SOIC , Bulk in tubes; 8S1, 8-lead (0.150” Wide Body), Plastic Gull
Wing Small Outline (JEDEC SOIC); Green, (Pb free, halogen free, ROHS)
-40 to 85 degrees C
Single-Wire
ATECC108A-SSHDA-T
8-lead SOIC , Tape and Reel; 8S1, 8-lead (0.150” Wide Body), Plastic
Gull Wing Small Outline (JEDEC SOIC); Green, (Pb free, halogen free,
ROHS) -40 to 85 degrees C
I2C
ATECC108A-SSHDA-B
8-lead SOIC , Bulk in tubes; 8S1, 8-lead (0.150” Wide Body), Plastic Gull
Wing Small Outline (JEDEC SOIC) ; Green, (Pb free, halogen free, ROHS)
-40 to 85 degrees C
I2C
ATECC108A-MAHCZ-T
8-pad UDFN, Tape and Reel; 8MA2, 8-pad, 2 x 3 x 0.6 mm Body,
Thermally Enhanced Plastic Ultra-Thin Dual Flat No Lead Package
(UDFN) ; Green (Pb free, halogen free, ROHS), -40 to 85 degrees C
Single-Wire
ATECC108A-MAHDA-T
8-pad UDFN, Tape and Reel; 8MA2, 8-pad, 2 x 3 x 0.6 mm Body,
Thermally Enhanced Plastic Ultra-Thin Dual Flat No Lead Package
(UDFN) Green (Pb free, halogen free, ROHS), -40 to 85 degrees C
I2C
ATECC108A-RBHCZ-T
3-lead Contact, Tape and Reel; 2.5mm x 6.5mm body, 2.0mm pitch
(Sawn) -40 to 85 degrees C
Single-Wire
Crypto Products REAL.EASY Training Manual: 2Q2015 r5
Qty per reel
/tube (units)
Minimum
Order Quantity
(MOQ) (units)
4,000
12,000
100
10,000
4,000
12,000
100
10,000
15,000
15,000
15,000
15,000
5,000
10,000
91
79.
Atmel CryptoAuthentication Device Ordering Guide: ATSHA204A
Atmel Ordering Code
Package Type
Interface
Configuration
ATSHA204A-SSHCZ-T
8-lead SOIC , Tape and Reel; 8S1, 8-lead (0.150” Wide Body), Plastic Gull
Wing Small Outline (JEDEC SOIC) ; Green, (Pb free, halogen free, ROHS)
-40 to 85 degrees C
Single-Wire
ATSHA204A-SSHDA-T
8-lead SOIC , Tape and Reel; 8S1, 8-lead (0.150” Wide Body), Plastic Gull
Wing Small Outline (JEDEC SOIC) Green, (Pb free, halogen free, ROHS) 40 to 85 degrees C
I2C
ATSHA204A-SSHDA-B
8-lead SOIC , Bulk in tubes; 8S1, 8-lead (0.150” Wide Body), Plastic Gull
Wing Small Outline (JEDEC SOIC) Green, (Pb free, halogen free, ROHS) 40 to 85 degrees C
I2C
ATSHA204A-XHCZ-T
ATSHA204A-XHDA-T
8-lead TSSOP, Tape and Reel; 8X, 8-lead 4.4mm Body, Plastic Thin
Shrink Small Outline Package (TSSOP)
-40 to 85 degrees C
8-lead TSSOP, Tape and Reel; 8X, 8-lead 4.4mm Body, Plastic Thin
Shrink Small Outline Package (TSSOP)
-40 to 85 degrees C
Single-Wire
I2C
ATSHA204A-STUCZ-T
3-lead SOT23, Tape and Reel; 3TS1, 3-lead, 1.30mm Body, Plastic Thin
Shrink Small Outline Package (Shrink SOT) -40 to 85 degrees C
Single-Wire
ATSHA204A-MAHCZ-T
8-pad UDFN, Tape and Reel; 8MA2, 8-pad, 2 x 3 x 0.6 mm Body,
Thermally Enhanced Plastic Ultra-Thin Dual Flat No Lead Package
(UDFN) ; Green (Pb free, halogen free, ROHS), -40 to 85 degrees C
Single-Wire
ATSHA204A-MAHDA-T
8-pad UDFN, Tape and Reel; 8MA2, 8-pad, 2 x 3 x 0.6 mm Body,
Thermally Enhanced Plastic Ultra-Thin Dual Flat No Lead Package
(UDFN) ; Green (Pb free, halogen free, ROHS), -40 to 85 degrees C
I2C
ATSHA204A-RBHCZ-T
3-lead Contact, Tape and Reel; 2.5mm x 6.5mm body, 2.0mm pitch
(Sawn) -40 to 85 degrees C
Single-Wire
Qty per reel
/tube (units)
Minimum
Order Quantity
(MOQ) (units)
4,000
12,000
4,000
12,000
100
10,000
4,000
4,000
12,000
12,000
15,000
15,000
15,000
15,000
15,000
15,000
5000
10000
8 pad UFDN NiPdAu Lead finish. 8-lead SOIC NiPdAu Lead finish
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80.
Atmel CryptoAuthentication Device Ordering Guide: ATAES132A
Atmel Ordering
Code
Package Type
Interface
Configuration
ATAES132A-SH-ER
8-lead SOIC , Bulk in tubes; 8S1, 8-lead (0.150” Wide Body), Plastic
Gull Wing Small Outline (JEDEC SOIC) Green, (Pb free, halogen
free, ROHS) -40 to 85 degrees C
I2C
ATAES132A-SH-ERT
8-lead SOIC , Tape and Reel; 8S1, 8-lead (0.150” Wide Body), Plastic
Gull Wing Small Outline (JEDEC SOIC) Green, (Pb free, halogen
free, ROHS) -40 to 85 degrees C
I2C
ATAES132A-M-ERT
8-pad UDFN, Tape and Reel; 8MA2, 8-pad, 2 x 3 x 0.6 mm Body,
Thermally Enhanced Plastic Ultra-Thin Dual Flat No Lead Package
(UDFN) ; Green (Pb free, halogen free, ROHS), -40 to 85 degrees C
I2C
ATAES132A-SH-EQ
8-lead SOIC , Bulk in tubes; 8S1, 8-lead (0.150” Wide Body), Plastic
Gull Wing ; Small Outline (JEDEC SOIC) ; Green, (Pb free, halogen
free, ROHS) -40 to 85 degrees C
ATAES132A-SHEQ-T
8-lead SOIC , Tape and Reel; 8S1, 8-lead (0.150” Wide Body), Plastic Gull
Wing Small Outline (JEDEC SOIC) ; Green, (Pb free, halogen free, ROHS) 40 to 85 degrees C
ATAES132A-MAHEQ-T
8-pad UDFN, Tape and Reel; 8MA2, 8-pad, 2 x 3 x 0.6 mm Body,
Thermally Enhanced Plastic Ultra-Thin Dual Flat No Lead Package
(UDFN) ; Green (Pb free, halogen free, ROHS), -40 to 85 degrees C
Crypto Products REAL.EASY Training Manual: 2Q2015 r5
Qty per reel
/tube (units)
Minimum Order
Quantity (MOQ)
(units)
100
10,000
4,000
12,000
15,000
15,000
100
10,000
4,000
12,000
15,000
15,000
SPI
SPI
SPI
93
81.
Atmel CryptoAuthentication Device Ordering Guide: ATECC508A
Atmel Ordering
Code
Package Type
Interface
Configuration
ATECC508ASSHCZ-T
8-lead SOIC , Tape and Reel; 8S1, 8-lead (0.150” Wide Body), Plastic Gull
Wing Small Outline (JEDEC SOIC) ; Green, (Pb free, halogen free, ROHS) 40 to 85 degrees C
Single-Wire
ATECC508ASSHCZ-B
8-lead SOIC , Bulk in tubes; 8S1, 8-lead (0.150” Wide Body), Plastic Gull
Wing Small Outline (JEDEC SOIC); Green, (Pb free, halogen free, ROHS) 40 to 85 degrees C
Single-Wire
ATECC508ASSHDA-T
8-lead SOIC , Tape and Reel; 8S1, 8-lead (0.150” Wide Body), Plastic Gull
Wing Small Outline (JEDEC SOIC); Green, (Pb free, halogen free, ROHS) -40
to 85 degrees C
I2C
ATECC508ASSHDA-B
8-lead SOIC , Bulk in tubes; 8S1, 8-lead (0.150” Wide Body), Plastic Gull
Wing Small Outline (JEDEC SOIC) ; Green, (Pb free, halogen free, ROHS)
40 to 85 degrees C
I2C
ATECC508AMAHCZ-T
8-pad UDFN, Tape and Reel; 8MA2, 8-pad, 2 x 3 x 0.6 mm Body, Thermally
Enhanced Plastic Ultra-Thin Dual Flat No Lead Package (UDFN) ; Green (Pb
free, halogen free, ROHS), -40 to 85 degrees C
ATECC508AMAHDA-T
ATECC508ARBHCZ-T
-
8-pad UDFN, Tape and Reel; 8MA2, 8-pad, 2 x 3 x 0.6 mm Body, Thermally
Enhanced Plastic Ultra-Thin Dual Flat, No Lead Package (UDFN)
Green (Pb free, halogen free, ROHS),
Qty per reel
/tube (units
Minimum
Order Quantity
(MOQ) (units)
4,000
12,000
100
10,000
4,000
12,000
100
10,000
15,000
15,000
15,000
15,000
5,000
10,000
Single-Wire
I2C
-40 to 85 degrees C
3-lead Contact, Tape and Reel; 2.5mm x 6.5mm body, 2.0mm pitch (Sawn)
-40 to 85 degrees C
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94
82. Atmel provides tools for every stage
Atmel provides kits to assist evaluators and developers at every stage from evaluation,
to product development, and all the way to small-run production. All of the Atmel kits
run ACES (Atmel CryptoAuthentication Evaluation System) software to configure the
CryptoAuthentication ™ devices. The combination of the user friendly hardware and
software presents users with exactly what is needed all along the way.
It All Starts
with a Demo
–Evaluation Kit
The AT88CK490 demo-evaluation kit contains three devices,
namely the ATSHA204A, ATECC108A, and ATAES132A (green
board). The AT88CK590 kit replaces the ATECC108A with the
ATECC508A (red board). The purpose of these boards is to
allow the user to use ACES software to configure and evaluate
the operation of any of the three crypto devices on the boards.
Once the user gets a feel for the operation and performance of
the devices, the next tools in the flow are the development kits.
Next is the AT88CK101 or the CryptoAuthXplained PRO Development
Kit
The AT88CK101 is a socketed kit thet allows the developer to program
CryptoAuthentication devices and then install those devices in their system.
Versions that support the various device package types are avialable.
Another development kit option is the CryptoAuthXplained Pro, which is a
standard 20-pin daughterboard that instantly adds CryptoAuthentication
devices to the Atmel Xplained and XpalinedPro development environment
boards.
AT88CK90000 Secure Personalization Kit (Option)
The Atmel AT88CK9000 allows programming of small batches of ATSHA204A devices
quickly, easily, and cost-effectively. This option decreases the cycle times of prototype, preproduction, and lower-volume production, improving time to market. The AT88CK900
securely programs up to 5 devices at the same time. Running production is as easy as
pressing a button...literally
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83. AT88CK490 and AT88CK590 Demo-Evaluation kits
The AT88CK490 demo-evaluation kit contains three devices, namely the ATSHA204A, ATECC108A, and ATAES132A (green board). The
AT88CK590 kit replaces the ATECC108A with the ATECC508A (red board). The purpose of these boards is to allow the user to use
ACES software to configure and evaluate the operation of any of the three crypto devices on the boards.
Once the user gets a feel for the operation and performance of the devices, the next tool in the flow is the AT88CK101 development board
Benefits



One dongle demonstrates three parts
Easy to use with ACES configuration environment
Can easily migrate from AT88CK490 and AT88CK590 demo-eval kits to AT88CK101 development kit
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84. CryptoAuthXplained Pro Development Kit
Another development kit Atmel offers is called CryptoAuthXplained Pro, which is a standard 20-pin header (daughterboard) that instantly adds
CryptoAuthentication(TM) devices to the Atmel Xplained and XpalinedPro developpment environment boards.
CryptoXplained runs ACES software.
The board supports ATSHA204A, ATECC508A,or ATAES132A in embedded design applications. This kit gives engineers, developers, and decision
makers a tool to understand the device architecture and its uses for product authentication, confidential file protection, perform two-factor logons, or
prevent software piracy. Complete source code for the Atmel CryptoAuthentication devices is available in ASF (Atmel Software Framework).
Schematics, Gerber files, and a bill of materials are also available.
The software that you develop on the PC using this system can also serve as the base for porting code to an embedded microcontroller. The Atmelprovided source code can be easily edited to integrate with ARM or other MCU platforms.
Benefits



Works with both Atmel Xplained and Xplained Pro MCU development boards
Users familiar with Xplained and Xplained Pro systems can easily try out CryptoAuthentication devices
Easy to configure devices with ACES configuration environment
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85. AT88CK9000 Production Programming Tool
Once the developer has created the desired configurations for the devices, small production runs can be accelerated by use of the AT88CK9000
programming board which securely programs up to 5 devices at the same time. The production configuration image is easily loaded through a USB
port. The image is then securely stored on the board as an
XML file generated by ACES.
Running production is as easy as pressing a button...literally.
The Atmel AT88CK9000 Secure Personalization kit for
CryptoAuthentication allows programming of small batches of
ATSHA204A devices quickly, easily, and cost-effectively. The
AT88CK9000 decreases the cycle times of prototype, preproduction, and lower-volume production, improving time to
market. The board is powered by the Atmel ARM and AVR®
processors and includes a display to provide valuable user
feedback. Additionally, a comprehensive User Guide is
downloadable from www.atmel.com.
Benefits

Speed time to market by making early production
runs


Easy to program devices
Can program up to 5 devices at the same time
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86. “ACES” (Atmel Crypto Evaluation Studio) Software
http://www.atmel.com/tools/ATMELCRYPTOEVALUATIONSTUDIO_ACES.aspx for detailed information about using ACES. An example of the ACES
configuration screen is shown below:
Benefits
 ACES works on all Atmel crypto demo,
development, and production systems
 Wizards and demos make it easy to learn
about CryptoAuthentication devices
 Demo code can be used as basis of
development code
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87.
Atmel CryptoAuthentication Kit Ordering Guide
Name
AT88CK490 DemoEvaluation Kit
Function
Very low cost and easy
demonstration and
evaluation in PC
environment
Ordering Code
AT88CK490
Detailed Description
Evaluation kit for Atmel
ATSHA204A, ATECC108A,
and ATAES132A
CryptoAuthentication
devices.
Kit Contents

USB dongle
20-pin
daughterboard
User plugs kit into USB port
and downloads ACES DemoEvaluation software
CryptoAuthXplained
Pro Daughterboard
Daughterboard that adds
CryptoAuthentication(TM)
devices to the Atmel
Xplained and XplainedPro
series of MCU
development boards.
ATCryptoAuthXplained
Pro
Standard 20-pin header
(daughterboard) with
ATSHA204A, ATECC508A,
and ATAES132A devices
Runs ACES software

CryptoAuthXplained
Daughterboard
Daughterboard that adds
CryptoAuthentication(TM)
devices to the Atmel
Xplained and XplainedPro
series of MCU
development boards.
ATCryptoAuthXplained
Standard 10-pin header
(daughterboard) with
ATSHA204A, ATECC508A,
and ATAES132A devices
Runs ACES software
 10-pin
daughterboard
AT88CK590 DemoEvaluation Kit
Very low cost and easy
demonstration and
evaluation in PC
environment
AT88CK590
Evaluation kit for Atmel
ATSHA204A, ATECC508A,
and ATAES132A
CryptoAuthentication
devices.

USB dongle
User plugs kit into USB port
and downloads ACES DemoEvaluation software
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AT88CK101
Development Kit
(SOT23)
Single socket secure
development kit.
Connects to a PC via USB
and also supports Atmel
Xplained Pro series
AT88CK101SK-TSUXPRO
Socketed kit for software
development of security
applications on the Atmel
ATSHA204A
CryptoAuthentication device
in SOT-23 packages.
Runs ACES software
AT88CK101
Development Kit (8SOIC)
AT88CK101
Development Kit (8UDFN)
AT88CK101
Development Kit
(3-lead RBH)
Single socket secure
development kit.
Connects to a PC via USB
and also supports Atmel
Xplained Pro series
Single socket secure
development kit.
Connects to a PC via USB
and also supports Atmel
Xplained Pro series
Single socket secure
development kit.
Connects to a PC via USB
and also supports Atmel
Xplained Pro series
AT88CK101SK-SSHXPRO
AT88CK101SK-MAHXPRO
AT88CK101SK-RBH




Socketed kit for software
development of security
applications on the Atmel
ATSHA204A, ATECC108A,
ATECC508A, and ATAES
132A CryptoAuthentication
devices in 8-pin SOIC
packages. Runs ACES
software

Socketed kit for software
development of security
applications on the Atmel
ATSHA204A, ATECC108A,
ATECC508A, and ATAES
132A CryptoAuthentication
devices in 8-pin UDFN
packages. Runs ACES
software

Socketed kit for software
development of security
applications on the Atmel
ATSHA204A, ATECC508A
and ATECC108A
CryptoAuthentication
devices in 3-contact RBH
packages. Runs ACES
software










Microbase
board*
Board with
3-lead SOT23
socket
IC samples
USB extension
cable
Microbase
board*
Board with
8-lead SOIC
socket
IC samples
USB extension
cable
Microbase
board*
Board with
8-lead UDFN
socket
IC samples
USB extension
cable
Microbase
board*
Board with
3-contact RBH
socket
IC samples
USB extension
cable
Note: * The Microbase is an Atmel AVR based AT90USB1287 board that provides a platform to test and develop applications directly with the Atmel CryptoAuthentication IC
The board comes with a JTAG port for debug as well as a USB connector to plug into a PC
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Atmel CryptoAuthentication Kit Ordering Guide (Continued)
Name
Function
Ordering
Code
Detailed
Description
Kit Contents
AT88CK9000
Production
Tool
(UDFN8)
Secure
personalization
production tool for
CryptoAuthentication
devices in 8-pad
UDFN packages
AT88CK90008MA
AT88CK9000 Secure
Personalization kit allows
programming of small
batches of ATSHA204A
devices quickly, easily,
and cost-effectively.
Runs ACES software

AT88CK9000
Production
Tool
(SOIC8)
Secure
personalization
production tool for
CryptoAuthentication
devices in 8-lead
SOIC packages
AT88CK90008SH
AT88CK9000 Secure
Personalization kit allows
programming of small
batches of ATSHA204A
devices quickly, easily,
and cost-effectively.
Runs ACES software

AT88CK9000
Production
Tool (3Contact
RBH)
Secure
personalization
production tool for
CryptoAuthentication
devices in 3-Contact
RBH packages
AT88CK9000RBH
AT88CK9000 Secure
Personalization kit allows
programming of small
batches of ATSHA204A
devices quickly, easily,
and cost-effectively.
Runs ACES software

AT88CK9000
Production
Tool
(SOT23-3)
Secure
personalization
production tool for
CryptoAuthentication
devices in 3-lead
SOT23-3 packages
AT88CK9000TSU
AT88CK9000 Secure
Personalization kit allows
programming of small
batches of ATSHA204A
devices quickly, easily,
and cost-effectively.
Runs ACES software









Secure Personalization
board
Multi-voltage power adapter
USB cable
Secure Personalization
board
Multi-voltage power adapter
USB cable
Secure Personalization
board
Multi-voltage power adapter
USB cable
Secure Personalization
board
Multi-voltage power adapter
USB cable
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88. Atmel Trusted Platform Module (TPM)
The Atmel Trusted Platform Module (TPM) is a complete FIPS 140-2 module
certified turnkey solution providing ultra-strong standards-based security for PCs
and embedded systems. Primary TPM capabilities include system integrity,
authentication, IP protection and secure communication. The core TPM building
blocks are the Atmel AVR® microcontroller, Atmel hardware security, and Atmel
EEPROM technologies. Security measures also include a variety of circuits to
detect and act upon voltage, temperature and frequency tampering. Available in
28-TSSOP and space-saving 4x4mm 32-QFN package options, Atmel TPM
devices provide cost effective, standards-based security solutions for all computing
devices that are connected to the internet.
Features include:

Full Trusted Computing Group (TCG) v1.2 rev. 116 specification
compliance








2048-bit RSA hardware crypto accelerator

Multiple I/O options: LPC, I2C, and SPI
Hardware SHA-1 accelerator
On-chip storage of up to 10 2048-bit RSA key pairs
High-quality FIPS 140-2 hardware random number generator
High reliability EEPROM for nonvolatile storage
Commercial and industrial grade temperature versions
3.3 V operation
BIOS and hardware drivers for Windows and Linux; third-party system and
application software.
Benefits



Turnkey solutions that include nonvolatile storage of keys and secrets.

Crypto acceleration provides high performance
TCG compliance means superior security and risk management
Hardware security defense mechanisms provide tamper detection and
response
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89. Trusted Platform Module (TPM) Security Features
The TPM is a cryptographic device with heavy cryptographic firepower, such as Platform Configuration Registers, protected user configurable nonvolatile storage, an enforced key hierarchy, and the ability to both seal and bind data to a TPM. It does not stop there. Atmel’s TPM has a variety of
Federal Information Processing Standards (FIPS) 140-2 certified cryptographic algorithms (such as RSA, SHA1, AES, RNG, and HMAC) and various
sophisticated physical security counter-measures. The TPM can be used right out of the box with standards-based commands defined by the
Trusted Computing Group, along with a set of Atmel-specific commands, which are
tested and ready to counter real world attacks.
Platform Configuration Registers: One of the important weapons contained in the
TPM is a bank of Platform Configuration Registers (PCRs), which use cryptographic
hashing functions. These registers can be used to ensure that only trusted code gets
loaded at boot time of the system. It does this by using the existing data in a PCR as
one input to a hashing function with the other input being new data. The result of that
hashing function becomes the new PCR value that will be used as the input to the
next hashing function with the next round of new data. This process provides security
by continuously changing the value of the PCR. As the PCR value gets updated, the
updated values can then be compared with known hash values stored in the system.
If the reference values previously stored in the TPM compare correctly with the newly
generated PCR values then the inputs to the hashing function (new data in the
diagram) are proven to have been exactly the same as the reference inputs whose
hash is stored on the TPM. Such matching of the hash values verifies the inputs as
being authentic.
Secure Boot: The PCR flow just described is very useful when enforcing secure boot of the system. Unless the hashes match showing that the
code is what it supposed to be the code will not be loaded. Even if a byte is added, deleted, or changed; or if a bit is modified then the system will not
boot. For secure boot, the data input to the hashing function is a piece of the BIOS (or operating system).
User Configurable Non-Volatile Storage
Another weapon is user-configurable non-volatile storage with multiple configuration options. What this means is that the user is presented with
several ways to restrict the access and use of the memory space, such as by password, physical presence of the user, and PCR states. Also the
memory space can be set up so that it can be written only once, not read until the next write or startup of the TPM, not written to until the next startup
of the TPM, and others.
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Trusted Platform Module (TPM) Features (Continued)
Enforced Key Hierarchy. The TPM also incorporates an enforced key hierarchy, which means that keys
must have another key acting as a parent key (i.e. a key higher in a hierarchy) for that key to get loaded into
the TPM. The authorization information for the parent key needs to be known before the child key can be
used, which adds another layer of security.
Binding and Sealing Data. Another part of the TPM’s arsenal is the ability to bind and/or seal data to the
TPM. A seal operation keeps the data contained (i.e. “sealed”) so that it can only be accessed if a particular
pre-defined configuration of the system has been reached. This pre-defined configuration is held within the
PCRs on the TPM. The TPM will not unseal the data until the platform configuration matches the
configuration stored within the PCRs. A bind operation creates encrypted data blobs (i.e. binary large
objects) that are bound to a private key that is held within the TPM. The data within the blob can only be
decrypted with the private key in the TPM. Thus, the data is said to be “bound” to that key. Such keys can
be reused for different sets of data.
FIPS 140-2 Certified. Atmel has dozens of FIPS 140-2 full module-level certified devices with various I/O’s
including LPC, SPI, and I2C. The TPM uses a number of FIPS certified algorithms to perform its operations.
These standards were developed, tested, and certified by the United States federal government for use in
computer systems. The TPM’s FIPS certified algorithms include RSA, SHA1, HMAC, AES, RNG and CVL
(see the following link: http://csrc.nist.gov/groups/STM/cmvp/documents/140-1/140val-all.htm for more details on Atmel’s TPM FIPS certifications).
Active Metal Shield: The TPM has built-in physical armor of its own. A serpentine active metal shield with tamper detection covers the entire device.
If someone attempts to penetrate this shield to see the structures beneath it, the TPM can detect this and go into a fault condition that prevents
further actions on the TPM.
You might be asking, “Why those functions can’t just be done in software?” While some of the protections can be provided in software, software
alone is not as robust as a hardware-based system. That is because software has bugs, despite how hard the developers try to eliminate them, and
hackers can exploit those bugs to gain access to supposedly secure systems. TPM on the other hand stores secret keys in protected hardware that
hackers cannot get access to, and they cannot attack what they cannot see.
The TPM embeds intelligence via an on-board microcontroller to manage and process cryptographic functions. The commands used by the Atmel
TPM have been defined and vetted by the Trusted Computing Group (TCG), which is a global consortium of companies established to define robust
standards for hardware security. The Atmel TPM has been successfully tested against TCG’s Compliance Test Suite to ensure conformance.
Security is also enhanced because secrets never leave the TPM unless they have been encrypted.
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90. Authentication Using TPM
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91. Secure Boot Using TPM for Platform Integrity
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92.
Atmel Trusted Platform Module (TPM) Device Selector Guide
Trusted Platform Modules
AT97SC3204
AT97SC3205
Status
Datasheet Status
Description
Full Production
Full Data Sheet (NDA required)
Trusted Platform Module with single-chip strong hardware-based asymmetric-key (RSA) security for PCs and embedded
processors. Turnkey system integrating Atmel's AVR® microcontroller, EEPROM, and security technology.
TCG Version
TCG version 1.2
Function(s)
Authentication/ Key Generation / Protected key storage
Authentication Modes
SHA1/ HMAC / RSA
Crypto Algorithms
RSA 512-2048
Key Length
2048
Secure boot
SHA
Key Exchange
Key Authorization
RSA
Key Creation
Command Authorization
Commands
103
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93.
Atmel Trusted Platform Module (TPM) Device Selector Guide (Continued)
Trusted Platform Modules
AT97SC3204
Power (min.)
AT97SC3205
3 mA
80 uA
Vcc
3.3V
EEPROM size
2.1Kbytes
Key Offload & Reload
Yes
Factory Unique ID
2048 bit Endorsement Key
Packages
I/O Interface
TSSOP28, QFN32
I2C (T-version), LPC
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94.
Atmel Trusted Platform Module (TPM) Device Selector Guide (Continued)
Trusted Platform Modules
AT97SC3204
AT97SC3205
CC EAL 3+ (4+ Pending)
-
-
Internal clock generation
FIPS 140-2 Certified
FIPS 140-2 Certification (Pending)
FIPS certified Random Number Generator (RNG) available on demand for external use
Optional Embedded X.509 certificates (signed endorsement keys)
Turnkey with Atmel AVR® microcontroller
Special
Features
Common root of trust
Active Shield
Randomized math ops
No probe or test points
FIPS 140-2 certified algorithms
No need for firmware development (turnkey)
Flexible Architecture - multiple security in one chip
Data independent crypto execution
Target
Apps
Optimized for standards based Public Key Infrastructure internet / network applications such as Tablets, Phablets, PC's, Access Points,
Micro Cells, Routers, Servers, MFP's, x86 based machines, and embedded systems
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95.
Atmel Trusted Platform Module (TPM) Device Ordering Guide
Part No.
Pkg Type
Material Description
Interface
Qty per
MOQ
Comments
reel /tube
AT97SC3204-X2A1A-10
28 TSSOP,
4.4mm
Lead-free, RoHS v1.2 rev 116, EK, COMM
Temp
LPC
1000
1,000
AT97SC3204-U2A1A-10
28 TSSOP,
4.4mm
Lead-free, RoHS v1.2 rev 116, EK, IND
Temp
LPC
1000
1,000
AT97SC3204-X2A1A-20
28 TSSOP,
4.4mm
Lead-free, RoHS v1.2 rev 116, signed EK,
COMM Temp
LPC
1000
1,000
AT97SC3204-U2A1A-20
28 TSSOP,
4.4mm
Lead-free, RoHS v1.2 rev 116, signed EK,
IND Temp
LPC
1000
1,000
40 QFN
Lead-free, RoHS v1.2 rev 116, EK, COMM
Temp
LPC
1000
1,000
40 QFN
Lead-free, RoHS v1.2 rev 116, EK, IND
Temp
LPC
1000
1,000
40 QFN
Lead-free, RoHS v1.2 rev 116, signed EK,
COMM Temp
LPC
1000
1,000
40 QFN
Lead-free, RoHS v1.2 rev 116, signed EK,
IND Temp
LPC
1000
1,000
28 TSSOP
Lead-free, RoHS v1.2 rev 116, EK, COMM
Temp
I2C
1000
1,000
Not recommended for new
designs. Use AT97SC3205T
28 TSSOP
Lead-free, RoHS v1.2 rev 116, with EK,
IND Temp
I2C
1000
1,000
Not recommended for new
designs. Use AT97SC3205T
40 QFN
Lead-free, RoHS v1.2 rev 116, with EK,
COMM Temp
I2C
1000
1,000
Not recommended for new
designs. Use AT97SC3205T
40 QFN
Lead-free, RoHS v1.2 rev 116, with EK,
IND Temp
I2C
1000
1,000
Not recommended for new
designs. Use AT97SC3205T
AT97SC3204-X2MA-10
AT97SC3204-U2MA-10
AT97SC3204-X2MA-20
AT97SC3204-U2MA-20
AT97SC3204T-X2A1B-10
AT97SC3204T-U2A1B-10
AT97SC3204T-X2MB-10
AT97SC3204TU2MB-10
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96.
Atmel Trusted Platform Module (TPM) Device Ordering Guide
Part No.
Pkg
Material Description
Interface
Type
Qty per
MOQ
reel /tube
28-pin
4.4mm
TSSOP
Commercial Temp (0°C to 70°C)
Lead-free, RoHS v1.2 rev 116 SPI TPM
SPI
1000
1,000
28-pin
4.4mm
TSSOP
Industrial Temp (-40°C to 85°C)
Lead-free, RoHS v1.2 rev 116 SPI TPM
SPI
1000
1,000
28-pin
4.4mm
TSSOP
Commercial Temp (0°C to 70°C)
Lead-free, RoHS v1.2 rev 116 SPI TPM
with Signed Real Mode EK, with 2066B
User NV
SPI
1000
1,000
AT97SC3205-U3A1220
28-pin
4.4mm
TSSOP
Industrial Temp (-40°C to 85°C)
Lead-free, RoHS v1.2 rev 116 SPI TPM
with Signed Real Mode EK, with 2066B
User NV
SPI
1000
1,000
AT97SC3205T-X3A1310
28-pin
4.4mm
TSSOP
Commercial Temp (0°C to 70°C)
Lead-free, RoHS v1.2 rev 116 I2C TPM
with Real Mode EK, with 2066B User NV
I2C
1000
1,000
AT97SC3205T-U3A1310
28-pin
4.4mm
TSSOP
Industrial Temp (-40°C to 85°C)
Lead-free, RoHS v1.2 rev 116 I2C TPM
with Real Mode EK, with 2066B User NV
I2C
1000
1,000
AT97SC3205T-X3A1320
28-pin
4.4mm
TSSOP
Commercial Temp (0°C to 70°C)
Lead-free, RoHS v1.2 rev 116 I2C TPM
with signed Real Mode EK, (X.509 cert)
with 2066B User NV
I2C
1000
1,000
AT97SC3205T-U3A1320
28-pin
4.4mm
TSSOP
Industrial Temp (-40°C to 85°C)
Lead-free, RoHS v1.2 rev 116 I2C TPM
with signed Real Mode EK, (X.509 cert)
with 2066B User NV
I2C
1000
1,000
AT97SC3205-X3A12-10
AT97SC3205-U3A1210
AT97SC3205-X3A12-20
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97. Trusted Platform Module (TPM)
Kits
The Trusted Platform Module Development kits are custom USB
based development boards based upon the Atmel SAM4S
ARM microcontroller and Atmel Trusted Platform Module (TPM)
devices. User-friendly demonstration and evaluation software is
provided on a USB flash drive. The drive contains demonstration
Source Code, hex images for reloading the demo code (if
necessary), Trusted Computing Group (TCG) Documentation, and
Kit Schematics. A USB extension cable is also included. The kit is
updateable with the latest firmware, when available.
The board contains various functional sections including one of the
Atmel AT97SC3204 TPM devices, a 33 MHz Clock Generator
(AT97SC3204 only), reset Switch, RC reset delay, decoupling
capacitors, pull-up and pull-down resistors, and test points, among
other things.
Benefits


Easy way to understand the operation of TPM devices


Connects directly to PC via USB port
Source code, hex images, TCG documentation and
schematics all included
Updatable code
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98. Trusted Platform Module (TPM) Kits Selector Guide
Name and
Function
Ordering Code
AT97SC3205TSDK2
AT97SC3205PSDK2
Development
Kit for
AT97SC3205
T I2C TPM
Device
Development
Kit for
AT97SC3205
P SPI TPM
Device
Detailed
Kit
Description
Contents
Custom USB based development board based upon
the Atmel SAM4S ARM microcontroller and Atmel
AT97SC3205T Trusted Platform Module (TPM)
device with I2C interface.
User-friendly
demonstration and evaluation software is provided
on a USB flash drive. The drive contains
demonstration Source Code, hex images for
reloading the demo code (if necessary), Trusted
Computing Group (TCG) Documentation, and Kit
Schematics. A USB extension cable is also
included. The kit is updateable with the latest
firmware, when available. (Please contact
[email protected] for more details on
demonstration software updates.)

Custom USB based development board based upon
the Atmel SAM4S ARM microcontroller and Atmel
AT97SC3205P Trusted Platform Module (TPM)
device with SPI interface.
User-friendly
demonstration and evaluation software is provided
on a USB flash drive. The drive contains
demonstration Source Code, hex images for
reloading the demo code (if necessary), Trusted
Computing Group (TCG) Documentation, and Kit
Schematics. A USB extension cable is also
included. The kit is updateable with the latest
firmware, when available. (Please contact
[email protected] for more details on
demonstration software updates.)





AT97SC3205
T I2C TPM
board (TCG
v1.2)
USB
extension
cable
USB Flash
drive
\
AT97SC3205
P SPI TPM
board (TCG
v1.2)
USB
extension
cable
USB Flash
drive
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99. FAQs: Some important questions:
Question 1:
I have AES cryptography already, so why do I need anything more?
If I am encrypting, isn’t that all the security I need?
AES is an algorithm that scrambles (i.e. encrypts) information. The scrambled information can
then be transferred somewhere else or stored in encrypted form and will remain unusable until
it is unscrambled (decrypted) into its original form. AES requires a key to encrypt and the same
key to decrypt. Both the transmitter of the encrypted information and the receiver of it must
store that key and keep that key secret on both sides. If the key is not kept secret on either
side then the information can be obtained by unintended outside parties, which defeats the
whole purpose. So, securely storing the key is one of the most critical parts of security. The
memory where the key is stored must be able to withstand attacks that try to read the key(s).
Hardware security devices, like Atmel’s CryptoAuthentication devices, offer a method of
protecting secret keys that restrict access and provide key generation and management.
Hardware security is much stronger then software based security because of the defense
mechanisms that are on hardware security devices that repel attacks of various types.
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Question 2:
I have heard that security has rankings, and that they rank something like this
4) ECC.
1) SHA, 2) AES, 3) RSA,
Does Atmel have the highest ranking?
In essence, security is a function of two main critical factors: 1) The length of the key used by the
cryptographic algorithms, and 2) the mathematical operations that are employed by the
cryptographic algorithms. The strength of security, therefore, depends on both the key size and
the specific algorithms employed. So, any of these algorithms might be stronger or weaker than
any other. Among most cryptographic experts, the following key sizes are considered to be
approximately similar in strength: SHA-256, AES-128, RSA-3072 and ECC-256. The letters depict
the algorithm (e.g. SHA) and the numbers after the dash represent the length of the key (e.g. 256). These important industry standard algorithms are all used in different ways depending on
the application, and many cryptographic systems even use several types of algorithms together to
Question 3:
Symmetric algorithms like AES and SHA use a single key for all products (e.g. the host and the clients), so
if the key is “broken” once, it would then be broken everywhere. Why would I want that?
The secret to understanding cryptography is that operations always depend on keeping secrets
(literally), and that means keeping the secret keys secret. Secure storage of the secrets (i.e. keys) is
what maintains a system’s integrity regardless of the algorithm.
Fortunately, because of clever cryptographic engineering it is not necessary for all systems using
symmetric algorithms to store the exact same key, even though this may sound counter-intuitive.
Using a technique called “key diversification” each client in the system can store a unique key that is
derived from its unique serial number and the key in the host (i.e. the root key). During the
authentication process with diversified keys the client sends the host the client’s diversified key and
the its unique serial number. The host can then derive the root key from that serial number and that
diversified key and compare that derived root key to the host’s stored root key. If the stored and
derived root keys match then the host knows that the client is real (i.e. authenticated).
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Question 4:
How can I justify the cost of an additional device to put security in every system I produce?
Adding security into a system is similar to buying insurance. The cost of a security breach is analogous
to the cost of an accident, fire, earthquake, or worse. The small cost of adding a crypto device ensures
that future catastrophic costs are not encountered.
Some of the benefits of adding a crypto device are as follows:
1) Increase revenue that can be lost due to the sale of unauthorized products (e.g. clones).
2) Improve revenue by preventing authorized subcontractors from using unauthorized sales
channels (i.e. selling clones in the gray market).
3) Minimize the cost of warranty support for non-authentic (i.e. cloned) products.
4) Enforce product and manufacturing licensing agreements to gain royalty income as agreed to.
5) Increase product family revenue by allowing only authorized accessories to operate on an OEM’s
system.
6) Conform to regulatory requirements such as HIPAA for medical information privacy in the US,
cross-border medical authentication recommendations in Europe, and new FDA
recommendations in the US for wireless medical device authentication.
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Question 5:
How do I protect the bus between the crypto device and microprocessor?
The question often comes up about how to ensure that the communication between the crypto device and the host MCU is not attacked by
a man-in-the-middle. In order to prevent a hacker from manipulating the bus between the two chips, the “Authentication OK” signal (i.e. the
Boolean response) can be uniquely encrypted by the crypto IC.
One way to secure the bus between the crypto IC and MCU is to perform an authentication on the result of crypto calculation on crypto
device (this is called the CheckMAC function). The idea is to make sure that when the authentication (i.e. crypto) device puts out the
Boolean response (which means “True” or “False”, or one or zero) from the Check MAC operation that the response cannot be tampered
with. The following paragraph explains in detail how that is done on a technical basis. However, the simple point here is that the Atmel’s
CryptoAuthentication devices contain a built-in mechanism to prevent an attack on the bus between the device and the MCU by effectively
encrypting that communication.
Technical Explanation: All the Atmel devices have a method of protecting the single Boolean bit that comes from the authentication chip
to the microprocessor. It involves using the second key that is both stored in the CryptoAuthentication device and compiled into the code.
After the successful completion of the “CheckMAC” operation, the second secret is copied into the TempKey register. Then the MCU
sends over a unique number (for example, time of day), which is then combined with that second secret using SHA and returned to the
MCU. The software on the MCU does the same combination using the compiled secret to see if it agrees with the result from the
authentication device. This is beneficial, because it means that you cannot just put a simple switch in the wire between the two and always
send a 1 (i.e. “True”).
The Atmel cryptographic ICs can also be set up to implement a secure boot with any MCU. In this mode the devices confirm the
authenticity of downloaded code.
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Question 6:
How can you encrypt with a one way algorithm like SHA, and isn’t XOR weak?
Many encryption algorithms like DES and AES use the XOR function as a key part of their implementation. Those
algorithms use a secret key to produce code that is XORed with the data in order to encrypt or decrypt that data. The
secrecy of the encrypted data depends upon how well the crypto algorithm mathematically scrambles that code, and
not upon the strength of the XOR function itself.
Hash algorithm-based devices (such as the ATSHA204) use the SHA256 algorithm in the same way to implement an
encrypted transport of data between the crypto device and a microprocessor.
During an encrypted read operation the crypto device uses a random number that is hashed with an internal secret
(i.e. the secret key) to create a result (i.e. a hash value or digest). That hash value (i.e. digest) is then XORed with
the value to be sent out of the device. (In other words, to encrypt the plaintext, the plaintext is XORed with the hash
of the secret key and a random number.) When that encrypted data is received outside of the crypto device, the
receiver will need to know the secret (i.e. secret key) that was used in order for that receiver to reproduce the
device’s internal value that he or she will XOR with the received encrypted data to mathematically reconstruct the
plaintext.
Similarly, on an encrypted write operation the chip inserts data based on the XOR of the internal calculated result.
The encrypted data sent to the device should be calculated using the same internal secrets or the chip will not
contain the expected value.
Since a completely new random number is created for each and every encrypted transport, and because the hash of
that random number with the secret key is used as the XOR code, then breaking such an encrypted transport would
require actually breaking the SHA-256 algorithm itself or obtaining the secret key.
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Question 7:
I have heard that my system isn’t secure unless I use a secure micro, is that true?
Secure Microprocessors are a great solution if your entire system can be implemented inside the provided
resources of the secure micro and the cost point of the product is appropriate for the system.
For today’s high performance systems, high-end microprocessors with external expandability or special purpose
hardware are required for most solutions. So, secure microprocessors are typically used as a separate companion
device to the system MCU. The security challenges then becomes two-fold: 1) Coupling the secure micro with the
unsecure operations of the high performance MCU, and 2) Protecting the bus between the two.
The best choice today to address those two issues is using a specialized crypto device (like Atmel’s
CryptoAuthentication) or a secure micro.
A very important point is that a secure device is only as good as the protection of the stored secrets (i.e. keys) in a
specialized crypto key storage device or in a secure MCU.
Special purpose Cryptographic IC devices (like CryptoAuthentication) focus solely on secure authentication and key
storage, and as a result they can be the more cost effective choice, and often far more secure.
The security functionality of a dedicated hardware authentication device is carefully tested and verified by the
manufacturer (e.g. Atmel), so the system designer does not need to worry about bugs that could be exploited by
attackers. In addition, with a hardware approach, the system designer does not need to be concerned about future
software updates of the software-based solution that can later expose a security weakness.
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Question 8:
How do I protect my valuable software IP?
The only way to fully protect the system software is to use a secure (i.e. smart card based)
microcontroller and store the entire system code within the device. In that way it cannot be read,
copied, or modified by an attacker. However, due to cost and other concerns, this will not be an
acceptable solution for most systems. On the other hand, a specialized cryptographic authentication
IC can provide excellent protection at a low cost.
In order to stop others from copying the system firmware and producing duplicate products (i.e.
clones), a crypto IC can be employed to match the firmware to legitimate products. Authorizing
firmware can be done by sending challenges to the cryptographic IC regularly during normal operation
and then checking for the correct response. If a system is build doesn’t include a correctly
programmed crypto IC, the firmware will fail to operate, thus protecting against cloning.
If, in the above scheme, the firmware is updated on a regular basis and new challenge-responses are
incorporated into the system, it becomes very difficult for a hacker to analyze the firmware and
remove the authorization checks. If a remote connection is available, implementing some of the
challenges randomly from a trusted backend server can make this nearly foolproof.
Processors like the Atmel ARM9 devices include an on-chip boot ROM. This ROM can be programmed to
use a crypto IC to check a firmware signature stored in the external flash prior to executing that
program. If unauthorized modifications have been made to the operating program, it will be
immediately detected and system operations can be interrupted.
When system architects are looking to protect sensitive algorithm, data, or protocols, the same secure
boot methodology can be used to decrypt the encrypted program module stored in the external flash.
The decryption key can be stored in the crypto IC since there is often no secure storage in the system
processor.
Question 9:
Is there licensing involved with using the Atmel devices?
The cryptographic algorithms used inside Atmel Crypto devices are industry-standard and approved
algorithms that do not require paying a license fee to Atmel or any third party. In addition, Atmel
offers communication layer source code free of charge for users to employ in any way without royalty.
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Question 10:
Why would Atmel’s chips be the preferred devices to use?
Atmel chips are designed from the ground up to provide an ultra-high level of hardware security.
Atmel is now beyond the third generation of devices that contain years of high security device making
experience and know-how. Some of the benefits that accrue to the Atmel devices are noted below:

Atmel uses proprietary test methods to eliminate test and probe access points

Other chips use standard layout methods, but Atmel implements a serpentine active metal shield
over the entire device preventing probing of internal secret nodes by providing a physical barrier
and by detecting and acting upon attempted attacks.

Atmel chips use the SHA-256 and ECC algorithms to ensure a long system life. CRC based systems
cannot stand up to modern cryptanalysis and SHA-1 is no longer recommended for new system use
by the US government.

Few authentication chips include a random number generator, forcing the system to use weak
methods to prevent replay attacks. Atmel devices include a multi-level FIPs level random number
generator on-chip for the highest quality output.

Atmel takes great care to analyze all possible input conditions to ensure that faulty or aggressive
input sequences will never result in the loss of secret data.

Many companies have the ability to design a straightforward digital device. But Atmel includes
environmental tampers to prevent operation outside the specification range, encrypts internal
busses to prevent emissions attacks, controls timing to prevent timing attacks, uses an internal
clock generator to prevent “over-clocking”, and provides many other security features.
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Question 11:
It seems hard to trust anything in the constantly changing digital world. How can we build IoT
systems that can continue to be trusted over time?
Trust is probably the most important part of any IoT system, because unless the data is trusted it is
of little real value. This should be obvious. In an IoT system the three pillars of security should be
present: Confidentiality, data integrity, and authenticity. The key to all of these is ensuring that the
secret keys and other important things stay secret. Storing digital IDs, passwords, secret keys,
private keys, names, and other important private data in software alone is not a great idea because
software has bugs, and can thus be hacked. Protected hardware-based key storage is the best
alternative.
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Question 12:
Constant change means constant software updates. How do you architect an IoT system to protect
this update process?
1. Protect the download image (don’t let it be modified, don’t let it be loaded into a clone system)
2. Repeatedly verify the code stored in the system (Flash), one way is secure boot
3. Use signatures to validate the code image, code fragments. Depends on an immutable public key,
correct cryptographic implementations. Don’t cheat on the algorithm or key size. Think about how
to update or augment the keys in the future.
Build a layered update process so that the unchangeable core can be as simple (and as well tested)
as possible. Push as much as possible to as secondary boot layer that can be validated by the
primary one.
Create a method which allows for flexibility in the download. Support broadcast images as well as
(possibly partial) targeted images.
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Questions designers should be asked:








Given the recently publicized attacks on unauthorized firmware modification, do you have a secure root
of trust to validate your firmware image?
How are the root private keys stored in your system?
Can any software (and potentially malware) access, copy and misuse those keys?
Do you have a validated implementation of your crypto firmware, or are you using open-source routines
that may have limited validation?
Are you using asymmetric algorithms (RSA, ECC) to create unique session keys?
Are the memory and performance requirements a problem for your system?
Do you have a cryptographic-quality random number generated, which is required for adequate
security?
Does it follow all the FIPS guidelines?
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© 2015 Atmel Corporation. All rights reserved.
Atmel®, logo and combinations thereof, CryptoAuthentication™ and others are registered trademarks or trademarks of Atmel Corporation or its subsidiaries. Other terms and
product names may be trademarks of others.
Disclaimer: the information in this document is provided in connection with Atmel products. No license, express or implied, by estoppel or otherwise, to any intellectual property right
is granted by this document or in connection with the sale of Atmel products. except as set forth in the Atmel terms and conditions of sales located on the Atmel website, Atmel
assumes no liability whatsoever and disclaims any express, implied or statutory warranty relating to its products including, but not limited to, the implied warranty of merchantability,
fitness for a particular purpose, or non-infringement. in no event shall Atmel be liable for any direct, indirect, consequential, punitive, special or incidental damages (including, without
limitation, damages for loss and profits, business interruption, or loss of information) arising out of the use or inability to use this document, even if Atmel has been advised of the
possibility of such damages. Atmel makes no representations or warranties with respect to the accuracy or completeness of the contents of this document and reserves the right to
make changes to specifications and products descriptions at any time without notice. Atmel does not make any commitment to update the information contained herein. Unless
specifically provided otherwise, Atmel products are not suitable for, and shall not be used in, automotive applications. Atmel products are not intended, authorized, or warranted for
use as components in applications intended to support or sustain life.
Atmel Corporation
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Unit 01-5 & 16, 19F
Business Campus
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© 2015 Atmel Corporation. All rights reserved.
Atmel®, Atmel logo and combinations thereof, Enabling Unlimited Possibilities®, and others are registered trademarks or trademarks of Atmel Corporation or its
subsidiaries. Other terms and product names may be trademarks of others.
Disclaimer: The information in this document is provided in connection with Atmel products. No license, express or implied, by estoppel or otherwise, to any intellectual property right is granted by this
document or in connection with the sale of Atmel products. EXCEPT AS SET FORTH IN THE ATMEL TERMS AND CONDITIONS OF SALES LOCATED ON THE ATMEL WEBSITE, ATMEL ASSUMES
NO LIABILITY WHATSOEVER AND DISCLAIMS ANY EXPRESS, IMPLIED OR STATUTORY WARRANTY RELATING TO ITS PRODUCTS INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. IN NO EVENT SHALL ATMEL BE LIABLE FOR ANY DIRECT, INDIRECT,
CONSEQUENTIAL, PUNITIVE, SPECIAL OR INCIDENTAL DAMAGES (INCLUDING, WITHOUT LIMITATION, DAMAGES FOR LOSS AND PROFITS, BUSINESS INTERRUPTION, OR LOSS OF
INFORMATION) ARISING OUT OF THE USE OR INABILITY TO USE THIS DOCUMENT, EVEN IF ATMEL HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. Atmel makes no
representations or warranties with respect to the accuracy or completeness of the contents of this document and reserves the right to make changes to specifications and products descriptions at any time
without notice. Atmel does not make any commitment to update the information contained herein. Unless specifically provided otherwise, Atmel products are not suitable for, and shall not be used in,
automotive applications. Atmel products are not intended, authorized, or warranted for use as components in applications intended to support or sustain life.
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