ASN1_item_sign_ctx()

Pull a NULL check for pkey->ameth up to before ameth is first accessed. An
EVP_PKEY created with EVP_PKEY_new() has ameth == NULL, so this check makes
sense, but it does not make sense to do it where it was.

1 files changed, 7 insertions, 3 deletions

diff --git a/src/lib/libcrypto/asn1/asn1_item.c b/src/lib/libcrypto/asn1/asn1_item.c
index d87a27b535..10b6780590 100644
--- a/src/lib/libcrypto/asn1/asn1_item.c
+++ b/src/lib/libcrypto/asn1/asn1_item.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: asn1_item.c,v 1.8 2023/06/15 12:44:17 tb Exp $ */
+/* $OpenBSD: asn1_item.c,v 1.9 2023/06/15 13:07:45 tb Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -248,6 +248,11 @@ ASN1_item_sign_ctx(const ASN1_ITEM *it, X509_ALGOR *algor1, X509_ALGOR *algor2,
                 return 0;
         }
 
+        if (pkey->ameth == NULL) {
+                ASN1error(ASN1_R_DIGEST_AND_KEY_TYPE_NOT_SUPPORTED);
+                return 0;
+        }
+
         if (pkey->ameth->item_sign) {
                 rv = pkey->ameth->item_sign(ctx, it, asn, algor1, algor2,
                     signature);
@@ -268,8 +273,7 @@ ASN1_item_sign_ctx(const ASN1_ITEM *it, X509_ALGOR *algor1, X509_ALGOR *algor2,
         }
 
         if (rv == 2) {
-                if (!pkey->ameth ||
-                    !OBJ_find_sigid_by_algs(&signid, EVP_MD_nid(type),
+                if (!OBJ_find_sigid_by_algs(&signid, EVP_MD_nid(type),
                     pkey->ameth->pkey_id)) {
                         ASN1error(ASN1_R_DIGEST_AND_KEY_TYPE_NOT_SUPPORTED);
                         return 0;