Compare encodings in X509_cmp as well as hash.

crypto/x509/x509_cmp.c

@@ -178,11 +178,24 @@ unsigned long X509_subject_name_hash_old(X509 *x)
  */
 int X509_cmp(const X509 *a, const X509 *b)
 {
+	int rv;
 	/* ensure hash is valid */
 	X509_check_purpose((X509 *)a, -1, 0);
 	X509_check_purpose((X509 *)b, -1, 0);
 
-	return memcmp(a->sha1_hash, b->sha1_hash, SHA_DIGEST_LENGTH);
+	rv = memcmp(a->sha1_hash, b->sha1_hash, SHA_DIGEST_LENGTH);
+	if (rv)
+		return rv;
+	/* Check for match against stored encoding too */
+	if (!a->cert_info->enc.modified && !b->cert_info->enc.modified)
+		{
+		rv = (int)(a->cert_info->enc.len - b->cert_info->enc.len);
+		if (rv)
+			return rv;
+		return memcmp(a->cert_info->enc.enc, b->cert_info->enc.enc,
+				a->cert_info->enc.len);
+		}
+	return rv;
 }
 #endif