commit 68878ccdd0c24e9522652e334175a48f488fadfd
author Valerio Setti <valerio.setti@nordicsemi.no> Thu Apr 10 23:30:26 2025 +0200
committer Valerio Setti <valerio.setti@nordicsemi.no> Wed May 07 09:06:52 2025 +0200
tree fe6a07dcc79a6be30687a29f019e5832f24fba88
parent 2439c4c14a5de74fe651861a265bf6488addc073

library: x509: simplify RSA-PSS management

- Do not store RSA-PSS signature options in CRL/CRT/CSR structures;
- During the parsing phase, just ensure that MGF1 hash alg is the same
  as the one used for the message.

Signed-off-by: Valerio Setti <valerio.setti@nordicsemi.no>

library/x509.c

diff --git a/library/x509.c b/library/x509.c
index 0571687..8ca7dde 100644
--- a/library/x509.c
+++ b/library/x509.c
@@ -715,38 +715,30 @@
  * Get signature algorithm from alg OID and optional parameters
  */
 int mbedtls_x509_get_sig_alg(const mbedtls_x509_buf *sig_oid, const mbedtls_x509_buf *sig_params,
-                             mbedtls_md_type_t *md_alg, mbedtls_pk_type_t *pk_alg,
-                             void **sig_opts)
+                             mbedtls_md_type_t *md_alg, mbedtls_pk_type_t *pk_alg)
 {
     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
 
-    if (*sig_opts != NULL) {
-        return MBEDTLS_ERR_X509_BAD_INPUT_DATA;
-    }
-
     if ((ret = mbedtls_oid_get_sig_alg(sig_oid, md_alg, pk_alg)) != 0) {
         return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_X509_UNKNOWN_SIG_ALG, ret);
     }
 
 #if defined(MBEDTLS_X509_RSASSA_PSS_SUPPORT)
     if (*pk_alg == MBEDTLS_PK_RSASSA_PSS) {
-        mbedtls_pk_rsassa_pss_options *pss_opts;
-
-        pss_opts = mbedtls_calloc(1, sizeof(mbedtls_pk_rsassa_pss_options));
-        if (pss_opts == NULL) {
-            return MBEDTLS_ERR_X509_ALLOC_FAILED;
-        }
+        mbedtls_md_type_t mgf1_hash_id;
+        int expected_salt_len;
 
         ret = mbedtls_x509_get_rsassa_pss_params(sig_params,
                                                  md_alg,
-                                                 &pss_opts->mgf1_hash_id,
-                                                 &pss_opts->expected_salt_len);
+                                                 &mgf1_hash_id,
+                                                 &expected_salt_len);
         if (ret != 0) {
-            mbedtls_free(pss_opts);
             return ret;
         }
-
-        *sig_opts = (void *) pss_opts;
+        /* Ensure MGF1 hash alg is the same as the one used to hash the message. */
+        if (mgf1_hash_id != *md_alg) {
+            return MBEDTLS_ERR_X509_INVALID_ALG;
+        }
     } else
 #endif /* MBEDTLS_X509_RSASSA_PSS_SUPPORT */
     {