From: Matt Caswell <matt@openssl.org>
Date: Fri, 4 Oct 2019 13:01:21 +0000 (+0100)
Subject: Send bad_record_mac instead of decryption_failed
X-Git-Tag: OpenSSL_1_1_1e~197
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=f1fd279cceb9eb7a0294a1eab8345c3193f40a0a;p=oweals%2Fopenssl.git

Send bad_record_mac instead of decryption_failed

The decryption failed alert was deprecated a long time ago. It can
provide an attacker too much information to be able to distinguish between
MAC failures and decryption failures and can lead to oracle attacks.
Instead we should always use the bad_record_mac alert for these issues.
This fixes one instance that still exists. It does not represent a
security issue in this case because it is only ever sent if the record is
publicly invalid, i.e. we have detected it is invalid without using any
secret material.

Reviewed-by: Tomas Mraz <tmraz@fedoraproject.org>
(Merged from https://github.com/openssl/openssl/pull/10093)

(cherry picked from commit 37133290832ac2d1389926eba7325125fdacbe8d)
---

diff --git a/ssl/record/ssl3_record.c b/ssl/record/ssl3_record.c
index d116ff0e90..d406adfb93 100644
--- a/ssl/record/ssl3_record.c
+++ b/ssl/record/ssl3_record.c
@@ -559,7 +559,7 @@ int ssl3_get_record(SSL *s)
             RECORD_LAYER_reset_read_sequence(&s->rlayer);
             return 1;
         }
-        SSLfatal(s, SSL_AD_DECRYPTION_FAILED, SSL_F_SSL3_GET_RECORD,
+        SSLfatal(s, SSL_AD_BAD_RECORD_MAC, SSL_F_SSL3_GET_RECORD,
                  SSL_R_BLOCK_CIPHER_PAD_IS_WRONG);
         return -1;
     }