From: Matt Caswell <matt@openssl.org>
Date: Mon, 12 Sep 2016 10:04:51 +0000 (+0100)
Subject: Abort on unrecognised warning alerts
X-Git-Tag: OpenSSL_1_1_0a~66
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=4bc54bf8b45ca0997ab6ffb13cc32b3ae1979ccc;p=openssl

Abort on unrecognised warning alerts

A peer continually sending unrecognised warning alerts could mean that we
make no progress on a connection. We should abort rather than continuing if
we receive an unrecognised warning alert.

Thanks to Shi Lei for reporting this issue.

Reviewed-by: Rich Salz <rsalz@openssl.org>
(cherry picked from commit 77a6be4dfc2ecf406c2559a99bea51317ce0f533)
---

diff --git a/ssl/record/rec_layer_s3.c b/ssl/record/rec_layer_s3.c
index 46870c054b..aa148ba490 100644
--- a/ssl/record/rec_layer_s3.c
+++ b/ssl/record/rec_layer_s3.c
@@ -1351,9 +1351,15 @@ int ssl3_read_bytes(SSL *s, int type, int *recvd_type, unsigned char *buf,
                 goto f_err;
             }
 #ifdef SSL_AD_MISSING_SRP_USERNAME
-            else if (alert_descr == SSL_AD_MISSING_SRP_USERNAME)
-                return (0);
+            else if (alert_descr == SSL_AD_MISSING_SRP_USERNAME) {
+                return 0;
+            }
 #endif
+            else {
+                al = SSL_AD_HANDSHAKE_FAILURE;
+                SSLerr(SSL_F_SSL3_READ_BYTES, SSL_R_UNKNOWN_ALERT_TYPE);
+                goto f_err;
+            }
         } else if (alert_level == SSL3_AL_FATAL) {
             char tmp[16];