Use X509_get_signature_info() when checking security levels.
Make signature security level checking more flexible by using
X509_get_signaure_info(): some signature methods (e.g. PSS, ED25519)
do not indicate the signing digest (if any) in the signature OID.
@@ -3201,8 +3201,6 @@ static int check_key_level(X509_STORE_CTX *ctx, X509 *cert)
*/
static int check_sig_level(X509_STORE_CTX *ctx, X509 *cert)
{
- int nid = X509_get_signature_nid(cert);
- int mdnid = NID_undef;
int secbits = -1;
int level = ctx->param->auth_level;
@@ -3211,14 +3209,8 @@ static int check_sig_level(X509_STORE_CTX *ctx, X509 *cert)
if (level > NUM_AUTH_LEVELS)
level = NUM_AUTH_LEVELS;
- /* Lookup signature algorithm digest */
- if (nid && OBJ_find_sigid_algs(nid, &mdnid, NULL)) {
- const EVP_MD *md;
-
- /* Assume 4 bits of collision resistance for each hash octet */
- if (mdnid != NID_undef && (md = EVP_get_digestbynid(mdnid)) != NULL)
- secbits = EVP_MD_size(md) * 4;
- }
+ if (!X509_get_signature_info(cert, NULL, NULL, &secbits, NULL))
+ return 0;
return secbits >= minbits_table[level - 1];
}
