From: Richard Levitte <levitte@openssl.org>
Date: Thu, 31 May 2018 09:12:34 +0000 (+0200)
Subject: ENGINE_pkey_asn1_find_str(): don't assume an engine implements ASN1 method
X-Git-Tag: OpenSSL_1_1_0i~95
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=13b578ada3106a4ce9b836f167ee520539f5fa8f;p=oweals%2Fopenssl.git

ENGINE_pkey_asn1_find_str(): don't assume an engine implements ASN1 method

Just because an engine implements algorithm methods, that doesn't mean
it also implements the ASN1 method.  Therefore, be careful when looking
for an ASN1 method among all engines, don't try to use one that doesn't
exist.

Fixes #6381

Reviewed-by: Tim Hudson <tjh@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6383)

(cherry picked from commit 1ac3cd6277f880fac4df313702d5e3b3814e56e2)
---

diff --git a/crypto/engine/tb_asnmth.c b/crypto/engine/tb_asnmth.c
index 480267daab..980c1277f9 100644
--- a/crypto/engine/tb_asnmth.c
+++ b/crypto/engine/tb_asnmth.c
@@ -170,7 +170,8 @@ static void look_str_cb(int nid, STACK_OF(ENGINE) *sk, ENGINE *def, void *arg)
         ENGINE *e = sk_ENGINE_value(sk, i);
         EVP_PKEY_ASN1_METHOD *ameth;
         e->pkey_asn1_meths(e, &ameth, NULL, nid);
-        if (((int)strlen(ameth->pem_str) == lk->len)
+        if (ameth != NULL
+                && ((int)strlen(ameth->pem_str) == lk->len)
                 && strncasecmp(ameth->pem_str, lk->str, lk->len) == 0) {
             lk->e = e;
             lk->ameth = ameth;