Re: [Qemu-devel] [PATCH V7 5/9] Support for BIOS interrupt handler

[Edgar E. Iglesias]

On Wed, Aug 31, 2011 at 09:58:58PM +0200, Edgar E. Iglesias wrote:
> On Wed, Aug 31, 2011 at 03:45:45PM -0400, Stefan Berger wrote:
> > This patch implements the TCG BIOS interrupt handler 1ah. It is for
> > example used by trusted grub.
> > 
> > This patch adds an implementation of SHA1 (following NIST specs., IETF RFC 
> > 3147
> > and Wikipedia) for speeding up measurements of code. Trusted Grub for 
> > example
> > makes use of this interface and measures (calculates SHA1) of the Linux 
> > kernel
> > and initrd. Those files can be rather large and hunting their bytes through
> > the TIS interface as part of the int handler commands invoked by trusted 
> > grub
> > does take quite some time due to the many vmexits the interface is creating
> > (one per byte).
> > 
> > There is also a threshold for the size of data to hash (100k) below which
> > the TPM is used and above the internal faster SHA1 algorithm is used.
> 
> Hi Stefan,
> 
> A question:
> Is there a reason for not reusing the SHA1 implementation from other 
> libraries,
> like OpenSSL?
> 
> I've got a couple of cryptographic device models on my end (some of them
> that I may contribute at some point) that will need the various SHA hashes
> and other ciphers.
> 
> In my case, there might be tons of data beeing hashed and when available,
> it would be nice to be able to use cryptographic hw acceleration which
> may be provided by OpenSSL engines. Or even, just heavily optimized
> assembly versions of them.

Woops, maybe this particular piece of code was not for QEMU proper...

Cheers