topic Re: Cryptographic Acceleration and Assurance Module in Vybrid Processors

Cryptographic Acceleration and Assurance Module

ngsari — Tue, 20 May 2014 12:06:03 GMT

I like to use CAAM Register interface (IP bus). But there is almost no information in the SECURITY documentation.
(The document is full of how to use those modules but lack of details.)
How can I access those registers with C ? (Or Assembly if I realy have to)
CAAM Status Register
RNG TRNG Status Register
RNG DRNG Status Register

Re: Cryptographic Acceleration and Assurance Module

matthieugaboria — Tue, 20 May 2014 13:49:10 GMT

Hello NG Sari,

Some information about these registers are page 628/629 of the VYBRIDSRM (RNG TRNG Status Register, RNG DRNG Status Register).

The CAAM base address can be found section 2.9 of the same document.

I hope it helps.

Re: Cryptographic Acceleration and Assurance Module

ngsari — Tue, 20 May 2014 14:12:40 GMT

Thank you so much :smileyhappy:

Re: Cryptographic Acceleration and Assurance Module

billpringlemeir — Fri, 23 May 2014 14:21:52 GMT

There are also Linux kernel drivers which might also be helpful; it has some sample source. The same CAAM engine is used on some iMx devices.

Re: Cryptographic Acceleration and Assurance Module

ngsari — Fri, 23 May 2014 15:55:50 GMT

Thank you Bill. It's very helpfull. That saves me from a lot pain and time :smileyhappy:

Re: Cryptographic Acceleration and Assurance Module

jackblather — Fri, 23 May 2014 21:32:26 GMT

Bill,

I looked at that link and example source isn't there.

On further research, I understand that the CAAM is accessed via the Linux Crypto drivers. Do you know where I can find examples on how to use this?

Thanks.

Re: Cryptographic Acceleration and Assurance Module

billpringlemeir — Mon, 26 May 2014 14:14:11 GMT

The link is to a Linux Driver that uses the CAAM. I don't know what you mean by example. The CAAM is extremely complex. The Linux CAAM driver shows how to use the registers (DECOs, Job rings and blobs) to do something. I referenced it as a working example of how to use the registers; together with the documentation it can be helpful. The user-space interface will depend on your Linux version. wikipedia.org, lwn article, and the current Linux crypto api might be useful. OpenSSL and others may possibly have a configuration to use this. At least it is possible to implement an OpenSSL crypto interface what would use the CAAM to accelerate things.