Re: [PATCH v2 0/3] tpm_pcr_extend() code split

[Jarkko Sakkinen]

On Wed, May 03, 2017 at 06:19:08PM +0200, Roberto Sassu wrote:
> This patch set moves TPM 1.2 specific code to a new function called
> tpm1_pcr_extend(). The purpose of splitting is to isolate TPM 2.0 code,
> so that it can be more easily modified to handle multiple digests.
> 
> With TPM 2.0, a Platform Configuration Register (PCR) could have multiple
> values, stored in locations called banks. Each bank stores the values
> of PCRs extended with the same hash algorithm.
> 
> Currently, the TPM kernel driver does not take advantage of stronger
> algorithms because PCRs are always extended with a SHA1 digest, padded
> with zeros to match the length of the input for the hash algorithm
> being used. Shortly after these patches, a new patch set will be provided
> to allow callers of tpm_pcr_extend() to pass a digest for each algorithm
> supported by the TPM.
> 
> In this patch set, TPM 1.2 specific code will prepare the command buffer
> with tpm_buf_init() which, in respect to the previous method, offers
> protection against buffer overflow. Moreover, CPU native to big-endian
> conversion has been removed from tags and ordinals definitions, as it is
> already done by tpm_buf_init().
> 
> Changelog:
> 
> v2
> - restored TPM_TAG_RQU_COMMAND definition in drivers/char/tpm/tpm.h
> - removed endianness conversion in TPM_TAG_RQU_COMMAND definition
> - removed '#include <linux/tpm_command.h>' in tpm-interface.c
>   and tpm-sysfs.c
> - restored TPM_ORD_ definitions in tpm-interface.c and tpm-sysfs.c
> 
> Roberto Sassu (3):
>   tpm: move endianness conversion of TPM_TAG_RQU_COMMAND to
>     tpm_input_header
>   tpm: move endianness conversion of ordinals to tpm_input_header
>   tpm: move TPM 1.2 code of tpm_pcr_extend() to tpm1_pcr_extend()
> 
>  drivers/char/tpm/tpm-interface.c | 79 ++++++++++++++++++++++------------------
>  drivers/char/tpm/tpm-sysfs.c     |  6 +--
>  drivers/char/tpm/tpm.h           |  2 +-
>  3 files changed, 47 insertions(+), 40 deletions(-)

Thanks for good quality patches! I'll test these but with quick skim
no complains whatsoever :-)

/Jarkko 

> 
> -- 
> 2.9.3
> 
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