Add error handling for EVP_DigestInit_ex().

A few EVP_DigestInit_ex() calls were left alone since reporting an
error would change the public API.

Changed internal ssl3_cbc_digest_record() to return a value due to the above
change.  It will also now set md_out_size=0 on failure.

This is based on part of BoringSSL's commit to fix malloc crashes:
https://boringssl.googlesource.com/boringssl/+/69a01608f33ab6fe2c3485d94aef1fe9eacf5364

ok miod@

1 files changed, 7 insertions, 3 deletions

diff --git a/src/lib/libssl/ssl_lib.c b/src/lib/libssl/ssl_lib.c
index e809ff0bc0..8dbd4a3f39 100644
--- a/src/lib/libssl/ssl_lib.c
+++ b/src/lib/libssl/ssl_lib.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssl_lib.c,v 1.93 2014/12/14 14:34:43 jsing Exp $ */
+/* $OpenBSD: ssl_lib.c,v 1.94 2014/12/15 00:46:53 doug Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -3033,8 +3033,12 @@ ssl_replace_hash(EVP_MD_CTX **hash, const EVP_MD *md)
 {
         ssl_clear_hash_ctx(hash);
         *hash = EVP_MD_CTX_create();
-        if (*hash != NULL && md != NULL)
-                EVP_DigestInit_ex(*hash, md, NULL);
+        if (*hash != NULL && md != NULL) {
+                if (!EVP_DigestInit_ex(*hash, md, NULL)) {
+                        ssl_clear_hash_ctx(hash);
+                        return (NULL);
+                }
+        }
         return (*hash);
 }