[PATCH v2] ima_evm_utils: extended calc_bootaggr to PCRs 8 - 9
From: Maurizio Drocco <hidden>
Date: 2020-06-23 18:01:35
Also in:
linux-integrity, lkml
Subsystem:
the rest · Maintainer:
Linus Torvalds
From: Maurizio <redacted> If PCRs 8 - 9 are set (i.e. not all-zeros), cal_bootaggr should include them into the digest. Signed-off-by: Maurizio Drocco <redacted> --- Changelog: v2: - Always include PCRs 8 & 9 to non-sha1 hashes v1: - Include non-zero PCRs 8 & 9 to boot aggregates src/evmctl.c | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-)
diff --git a/src/evmctl.c b/src/evmctl.c
index 1d065ce..46b7092 100644
--- a/src/evmctl.c
+++ b/src/evmctl.c@@ -1930,6 +1930,16 @@ static void calc_bootaggr(struct tpm_bank_info *bank) } } + if (strcmp(bank->algo_name, "sha1") != 0) { + for (i = 8; i < 10; i++) { + err = EVP_DigestUpdate(pctx, bank->pcr[i], bank->digest_size); + if (!err) { + log_err("EVP_DigestUpdate() failed\n"); + return; + } + } + } + err = EVP_DigestFinal(pctx, bank->digest, &mdlen); if (!err) { log_err("EVP_DigestFinal() failed\n");
@@ -1972,8 +1982,9 @@ static int append_bootaggr(char *bootaggr, struct tpm_bank_info *tpm_banks) /* * The IMA measurement list boot_aggregate is the link between the preboot * event log and the IMA measurement list. Read and calculate all the - * possible per TPM bank boot_aggregate digests based on the existing - * PCRs 0 - 7 to validate against the IMA boot_aggregate record. + * possible per TPM bank boot_aggregate digests based on the existing PCRs + * 0 - 9 to validate against the IMA boot_aggregate record. If the digest + * algorithm is SHA1, only PCRs 0 - 7 are considered to avoid ambiguity. */ static int cmd_ima_bootaggr(struct command *cmd) {
--
2.17.1