On Wed, Feb 06, 2019 at 11:57:18AM +0100, Roberto Sassu wrote: > Update > > This version of the patch set includes three additional patches (5-7/7) > that allow users of the TPM driver to provide a digest for each PCR bank to > tpm_pcr_extend(). The new patches have been included to facilitate the > review of all the changes to support TPM 2.0 crypto agility for reading and > extending PCRs. > > > Original patch set description > > The TPM driver currently relies on the crypto subsystem to determine the > digest size of supported TPM algorithms. In the future, TPM vendors might > implement new algorithms in their chips, and those algorithms might not > be supported by the crypto subsystem. > > Usually, vendors provide patches for the new hardware, and likely > the crypto subsystem will be updated before the new algorithm is > introduced. However, old kernels might be updated later, after patches > are included in the mainline kernel. This would leave the opportunity > for attackers to misuse PCRs, as PCR banks with an unknown algorithm > are not extended. > > This patch set provides a long term solution for this issue. If a TPM > algorithm is not known by the crypto subsystem, the TPM driver retrieves > the digest size from the TPM with a PCR read. All the PCR banks are > extended, even if the algorithm is not yet supported by the crypto > subsystem. > > PCR bank information (TPM algorithm ID, digest size, crypto subsystem ID) > is stored in the tpm_chip structure and available for users of the TPM > driver. > > Changelog > > v9: > - add comment for ima_load_kexec_buffer() in ima_init() > - move 'digests' and ima_init_digests() to ima_queue.c > - remove comment for TPM_RETRY > > v8: > - set digest array length in tpm_digest to new constant TPM_MAX_DIGEST_SIZE > - replace enum tpm_const with #define > - rename labels in init_trusted() > - allocate tpm_digest array after retrieving random data in init_digests() > > v7: > - use memchr_inv() in tpm2_get_pcr_allocation() > - add patch to move tpm_chip to include/linux/tpm.h > - add patch to set the tpm_chip argument in trusted.c to a pointer from > tpm_default_chip() > - remove definition of tpm_extend_digest > - remove code in tpm2_pcr_extend() to extend unused PCR banks with the > first digest passed by the caller of tpm_pcr_extend() > - remove count parameter from tpm_pcr_extend() and tpm2_pcr_extend() > - remove padding of SHA1 digest in tpm_pcr_extend() > - pre-allocate and initialize array of tpm_digest structures in > security/keys/trusted.c and security/integrity/ima/ima_init.c > > v6: > - squash patches 4-6 > - rename tpm_bank_list to tpm_extend_digest, extend_size and extend_data > members to size and data > - add comment in tpm2_init_bank_info() > > v5: > - rename digest_struct variable to digest > - add _head suffix to tcg_efi_specid_event and tcg_pcr_event2 > - rename digest_size member of tpm_bank_list to extend_size > - change type of alg_id member of tpm_bank_list from u8 to u16 > - add missing semi-colon in pcrlock() > > v4: > - rename active_banks to allocated_banks > - replace kmalloc_array() with kcalloc() > - increment nr_allocated_banks if at least one PCR in the bank is selected > - pass multiple digests to tpm_pcr_extend() > > v3: > - remove end marker change > - replace active_banks static array with pointer to dynamic array > - remove TPM2_ACTIVE_PCR_BANKS > > v2: > - change the end marker of the active_banks array > - check digest size from output of PCR read command > - remove count parameter from tpm_pcr_read() and tpm2_pcr_read() > > v1: > - modify definition of tpm_pcr_read() > - move hash algorithms and definition of tpm2_digest to include/linux/tpm.h > > > Roberto Sassu (6): > tpm: dynamically allocate the allocated_banks array > tpm: rename and export tpm2_digest and tpm2_algorithms > tpm: retrieve digest size of unknown algorithms with PCR read > tpm: move tpm_chip definition to include/linux/tpm.h > KEYS: trusted: explicitly use tpm_chip structure from > tpm_default_chip() > tpm: pass an array of tpm_extend_digest structures to tpm_pcr_extend() > > drivers/char/tpm/tpm-chip.c | 1 + > drivers/char/tpm/tpm-interface.c | 38 ++++---- > drivers/char/tpm/tpm.h | 117 ++--------------------- > drivers/char/tpm/tpm1-cmd.c | 12 +++ > drivers/char/tpm/tpm2-cmd.c | 139 ++++++++++++++++++++-------- > include/linux/tpm.h | 126 ++++++++++++++++++++++++- > include/linux/tpm_eventlog.h | 9 +- > security/integrity/ima/ima.h | 1 + > security/integrity/ima/ima_crypto.c | 10 +- > security/integrity/ima/ima_init.c | 4 + > security/integrity/ima/ima_queue.c | 27 +++++- > security/keys/trusted.c | 73 +++++++++++---- > 12 files changed, 349 insertions(+), 208 deletions(-) > > -- > 2.17.1 > Can you do two things: 1. Check the v3: https://patchwork.kernel.org/patch/10797181/. Needs to be applied first. 2. Check that this does not cause merge conflicts with the current imaster? If it does, fix them, and use --subject-prefix="RESEND,PATCH v10". Thanks. /Jarkko
