The existing in-kernel interface for extending a TPM PCR extends the SHA1 PCR bank. For TPM 1.2, that is the one and only PCR bank defined. TPM 2.0 adds support for multiple PCR banks, to support different hash algorithms. The TPM 2.0 Specification[1] recommends extending all active PCR banks. This patch set enhances the existing TPM 2.0 extend function and corresponding in-kernel interface to support extending all active PCR banks.
The first patch implements the TPM 2.0 capability to retrieve the list of active PCR banks. The second patch modifies the TPM 2.0 device driver extend function to support extending multiple PCR banks. The existing in-kernel interface expects only a SHA1 digest. Hence, to extend all active PCR banks with differing digest sizes for TPM 2.0, the SHA1 digest is padded with 0's as needed. This approach is taken to maintain backwards compatibility for the existing users (i.e. IMA) in order to continue working with both TPM 1.2 and TPM 2.0 without any changes and still comply with the TPM 2.0 Specification[1] requirement of extending all active PCR banks. This patch series has a prerequisite(header file tpm2.h) of TPM 2.0 event log patch series. [1] TPM2.0 Specification referred here is "TCG PC Client Specific Platform Firmware Profile for TPM 2.0" Nayna Jain (2): tpm: implement TPM 2.0 capability to get active PCR banks tpm: enhance TPM 2.0 PCR extend to support multiple banks drivers/char/tpm/tpm-chip.c | 4 ++ drivers/char/tpm/tpm-interface.c | 17 ++++- drivers/char/tpm/tpm.h | 8 ++- drivers/char/tpm/tpm2-cmd.c | 151 ++++++++++++++++++++++++++++++++------- drivers/char/tpm/tpm2.h | 53 ++++++++++++++ 5 files changed, 205 insertions(+), 28 deletions(-) -- 2.5.0 ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot _______________________________________________ tpmdd-devel mailing list tpmdd-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/tpmdd-devel
