Security matters now more than ever, so why isn’t security a standard feature in all digital systems? Luckily, there is a standard for security and it is literally standards-based. It is called TPM. TPM, which stands for Trusted Platform Module, can be thought of as a microcontroller that can take a punch, and come back for more.
The TPM is a small integrated circuit with an on-board microcontroller, secure hardware-based private key generation and storage, and other cryptographic functions (e.g. digital signatures, key exchange, etc.), and is a superb way to secure email, secure web access, and protect local data. It is becoming very clear just how damaging loss of personal data can be. Just ask Target stores, Home Depot, Brazilian banks, Healthcare.gov, JP Morgan, and the estimated billions of victims of the Russian “CyberVor” gang of hackers. (What the hack! You can also follow along with the latest breaches here.) The world has become a serious hackathon with real consequences; and, unfortunately, it will just get worse with the increase of mobile communications, cloud computing, and the growth of autonomous computing devices and the Internet of Things.
What can be done about growing threats against secure data?
The TPM is a perfect fit for overall security. So, just how does the TPM increase security? There are four main capabilities:
- Furnish platform integrity
- Perform authentication (asymmetric)
- Implement secure communication
- Ensure IP protection
These capabilities have been designed into TPM devices according to the guidance of an industry consortium called the Trusted Computing Group (TCG), whose members include many of the 800-pound gorillas of the computing, networking, software, semiconductor, security, automotive, and consumer industries. These companies include Intel, Dell, Microsoft, among many others. The heft of these entities is one of the vectors that is driving the strength of TPM’s protections, creation of TPM devices, and ultimately accelerating TPM’s adoption. The TPM provides security in hardware, which beats software based security every time. And that matters, a lot.
Atmel TPM devices come complete with cryptographic algorithms for RSA (with 512, 1024, and 2048 bit keys), SHA-1, HMAC, AES, and Random Number Generator (RNG). We won’t go into the mathematical details here, but note that Atmel’s TPM has been Federal Information Processing Standards (FIPS) 140-2 certified, which attests to its high level of robustness. And, that is a big deal. These algorithms are built right into Atmel TPMs together with supporting software serve to accomplish multiple security functions in a single device.
Each TPM comes with a unique key called an endorsement key that can also be used as part of a certificate chain to prevent counterfeiting. With over 100 commands, the Atmel TPM can execute a variety of actions such as key generation and authorization checks. It also provides data encryption, storage, signing, and binding just to name a few.
An important way that TPMs protect against physical attacks is by a shielded area that securely stores private keys and data, and is not vulnerable to the types of attacks to which software key storage is subjected.
But the question really is, “What can the TPM do for you?” The TPM is instrumental in systems that implement “Root of Trust” (i.e. data integrity and authentication) schemes.
Root of trust schemes use hashing functions as the BIOS boots to ensure that there have been no unwanted changes to the BIOS code since the previous boot. The hashing can continue up the chain into the OS. If the hash (i.e. digest) does not match the expected result, then the system can limit access, or even shut down to prevent malicious code from executing. This is the method used in Microsoft’s Bitlocker approach on PCs, for example. The TPM can help to easily encrypt an entire hard drive and that can only be unlocked for decryption by the key that is present on the TPM or a backup key held in a secure location.
Additionally, the TPM is a great resource in the embedded world where home automation, access points, consumer, medical, and automotive systems are required. As technology continues to grow to a wide spectrum of powerful and varying platforms, the TPM’s role will also increase to provide the necessary security to protect these applications.
Interested in learning more about Atmel TPM? Head here. To read about this topic a bit further, feel free to browse through the Bits & Pieces archive.
This blog was contributed by Ronnie Thomas, Atmel Software Engineer.