From 218a2680624cba1611e3dfc7d9b646d240e5f855 Mon Sep 17 00:00:00 2001 From: Eric Snowberg Date: Thu, 17 Aug 2023 10:04:07 -0400 Subject: certs: Reference revocation list for all keyrings Systems booted with shim have a Forbidden Signature Database called mokx. During boot, hashes and certs contained within the mokx are loaded into the blacklist keyring. When calling verify_pkcs7_message_sig the contents of the blacklist keyring (or revocation list) are referenced when validating keys on the platform keyring. Currently, when validating against the secondary or builtin keyrings, the revocation list is not referenced. Move up the check to allow the revocation list to be used with all keyrings, including the secondary and builtin, allowing the system owner to take corrective action should a vulnerability be found within keys contained within either keyring. Signed-off-by: Eric Snowberg Reviewed-by: Mimi Zohar Reviewed-by: Jarkko Sakkinen Signed-off-by: Jarkko Sakkinen --- certs/system_keyring.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/certs/system_keyring.c b/certs/system_keyring.c index 33841c91f12c..9de610bf1f4b 100644 --- a/certs/system_keyring.c +++ b/certs/system_keyring.c @@ -330,6 +330,12 @@ int verify_pkcs7_message_sig(const void *data, size_t len, if (ret < 0) goto error; + ret = is_key_on_revocation_list(pkcs7); + if (ret != -ENOKEY) { + pr_devel("PKCS#7 key is on revocation list\n"); + goto error; + } + if (!trusted_keys) { trusted_keys = builtin_trusted_keys; } else if (trusted_keys == VERIFY_USE_SECONDARY_KEYRING) { @@ -349,12 +355,6 @@ int verify_pkcs7_message_sig(const void *data, size_t len, pr_devel("PKCS#7 platform keyring is not available\n"); goto error; } - - ret = is_key_on_revocation_list(pkcs7); - if (ret != -ENOKEY) { - pr_devel("PKCS#7 platform key is on revocation list\n"); - goto error; - } } ret = pkcs7_validate_trust(pkcs7, trusted_keys); if (ret < 0) { -- cgit