integrity/platform_certs: Allow loading of keys in the static key management mode

On PLPKS enabled PowerVM LPAR, there is no provision to load signed
third-party kernel modules when the key management mode is static. This
is because keys from secure boot secvars are only loaded when the key
management mode is dynamic.

Allow loading of the trustedcadb and moduledb keys even in the static
key management mode, where the secvar format string takes the form
"ibm,plpks-sb-v0".

Signed-off-by: Srish Srinivasan <ssrish@linux.ibm.com>
Tested-by: R Nageswara Sastry <rnsastry@linux.ibm.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Nayna Jain <nayna@linux.ibm.com>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20250610211907.101384-4-ssrish@linux.ibm.com

diff --git a/security/integrity/platform_certs/load_powerpc.c b/security/integrity/platform_certs/load_powerpc.c
index c85febca3343e5470d9aab524f972ec50547f384..714c961a00f54048ef15b59612cfd50c7da2621e 100644 (file)
--- a/security/integrity/platform_certs/load_powerpc.c
+++ b/security/integrity/platform_certs/load_powerpc.c
@@ -75,12 +75,13 @@ static int __init load_powerpc_certs(void)
                return -ENODEV;
 
        // Check for known secure boot implementations from OPAL or PLPKS
-       if (strcmp("ibm,edk2-compat-v1", buf) && strcmp("ibm,plpks-sb-v1", buf)) {
+       if (strcmp("ibm,edk2-compat-v1", buf) && strcmp("ibm,plpks-sb-v1", buf) &&
+           strcmp("ibm,plpks-sb-v0", buf)) {
                pr_err("Unsupported secvar implementation \"%s\", not loading certs\n", buf);
                return -ENODEV;
        }
 
-       if (strcmp("ibm,plpks-sb-v1", buf) == 0)
+       if (strcmp("ibm,plpks-sb-v1", buf) == 0 || strcmp("ibm,plpks-sb-v0", buf) == 0)
                /* PLPKS authenticated variables ESL data is prefixed with 8 bytes of timestamp */
                offset = 8;