lkml.org 
[lkml]   [2020]   [Jun]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] ima_evm_utils: extended calc_bootaggr to PCRs 8 - 9
Date
From: Maurizio <maurizio.drocco@ibm.com>

If PCRs 8 - 9 are set (i.e. not all-zeros), cal_bootaggr should include
them into the digest.

Signed-off-by: Maurizio Drocco <maurizio.drocco@ibm.com>
---
src/evmctl.c | 16 +++++++++++++++-
1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/src/evmctl.c b/src/evmctl.c
index 1d065ce..554571e 100644
--- a/src/evmctl.c
+++ b/src/evmctl.c
@@ -1930,6 +1930,18 @@ static void calc_bootaggr(struct tpm_bank_info *bank)
}
}

+ if (strcmp(bank->algo_name, "sha1") != 0) {
+ for (i = 8; i < 10; i++) {
+ if (memcmp(bank->pcr[i], zero, bank->digest_size) != 0) {
+ 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");
@@ -1973,7 +1985,9 @@ 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.
+ * PCRs 0 - 9 to validate against the IMA boot_aggregate record. If PCRs
+ * 8 - 9 are not set (i.e. all-zeros) or the digest algorithm is SHA1, only
+ * PCRs 0 - 7 are considered.
*/
static int cmd_ima_bootaggr(struct command *cmd)
{
--
2.17.1
\
 
 \ /
  Last update: 2020-06-18 22:14    [W:0.082 / U:0.108 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site