Simplify the code in X509_get_pubkey_parameters(3)

by using X509_get0_pubkey(3) instead of X509_get_pubkey(3);
no functional change.

OK tb@

This is similar to the relevant part of the follwoing commit
from the OpenSSL 1.1.1 branch, which is still under a free licence,
but without the bug that commit introduced into this function in OpenSSL:

commit c01ff880d47392b82cce2f93ac4a9bb8c68f8cc7
Author: Dr. Stephen Henson <steve@openssl.org>
Date:   Mon Dec 14 13:13:32 2015 +0000

diff --git a/lib/libcrypto/x509/x509_vfy.c b/lib/libcrypto/x509/x509_vfy.c
index db2125b..93dac74 100644 (file)
--- a/lib/libcrypto/x509/x509_vfy.c
+++ b/lib/libcrypto/x509/x509_vfy.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: x509_vfy.c,v 1.98 2021/11/24 05:38:12 beck Exp $ */
+/* $OpenBSD: x509_vfy.c,v 1.99 2021/11/26 13:05:03 schwarze Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -2079,17 +2079,15 @@ X509_get_pubkey_parameters(EVP_PKEY *pkey, STACK_OF(X509) *chain)
                return 1;
 
        for (i = 0; i < sk_X509_num(chain); i++) {
-               ktmp = X509_get_pubkey(sk_X509_value(chain, i));
+               ktmp = X509_get0_pubkey(sk_X509_value(chain, i));
                if (ktmp == NULL) {
                        X509error(X509_R_UNABLE_TO_GET_CERTS_PUBLIC_KEY);
                        return 0;
                }
                if (!EVP_PKEY_missing_parameters(ktmp))
                        break;
-               else {
-                       EVP_PKEY_free(ktmp);
+               else
                        ktmp = NULL;
-               }
        }
        if (ktmp == NULL) {
                X509error(X509_R_UNABLE_TO_FIND_PARAMETERS_IN_CHAIN);
@@ -2098,14 +2096,12 @@ X509_get_pubkey_parameters(EVP_PKEY *pkey, STACK_OF(X509) *chain)
 
        /* first, populate the other certs */
        for (j = i - 1; j >= 0; j--) {
-               ktmp2 = X509_get_pubkey(sk_X509_value(chain, j));
+               ktmp2 = X509_get0_pubkey(sk_X509_value(chain, j));
                EVP_PKEY_copy_parameters(ktmp2, ktmp);
-               EVP_PKEY_free(ktmp2);
        }
 
        if (pkey != NULL)
                EVP_PKEY_copy_parameters(pkey, ktmp);
-       EVP_PKEY_free(ktmp);
        return 1;
 }