IMA does not measure duplicate buffer data since TPM extend is a very expensive operation. However, in some cases for integrity critical data, the measurement of duplicate data is necessary to accurately determine the current state of the system. Eg, SELinux state changing from 'audit', to 'enforcing', and back to 'audit' again. In this example, currently, IMA will not measure the last state change to 'audit'. This limits the ability of attestation services to accurately determine the current state of the integrity critical data on the system. This series addresses this gap by providing the ability to measure duplicate entries for integrity critical data, driven by policy. This series is based on the following repo/branch/commit: repo: https://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity.git branch: next-integrity-testing commit b3f82afc1041 ("IMA: Measure kernel version in early boot") Tushar Sugandhi (3): IMA: add policy condition to measure duplicate critical data IMA: update functions to read allow_dup policy condition IMA: add support to measure duplicate buffer for critical data hook Documentation/ABI/testing/ima_policy | 4 +++- security/integrity/ima/ima.h | 8 +++---- security/integrity/ima/ima_api.c | 15 +++++++------ security/integrity/ima/ima_appraise.c | 2 +- security/integrity/ima/ima_init.c | 2 +- security/integrity/ima/ima_main.c | 9 ++++---- security/integrity/ima/ima_policy.c | 31 ++++++++++++++++++++++++--- security/integrity/ima/ima_queue.c | 5 +++-- 8 files changed, 54 insertions(+), 22 deletions(-) -- 2.17.1
