1 files changed, 15 insertions, 30 deletions

diff --git a/src/lib/libssl/ssl_srvr.c b/src/lib/libssl/ssl_srvr.c
index f1a0c9ae03..e72593e6b1 100644
--- a/src/lib/libssl/ssl_srvr.c
+++ b/src/lib/libssl/ssl_srvr.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssl_srvr.c,v 1.28 2018/01/28 09:21:34 inoguchi Exp $ */
+/* $OpenBSD: ssl_srvr.c,v 1.29 2018/04/11 17:47:36 jsing Exp $ */
 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
  * All rights reserved.
  *
@@ -1772,36 +1772,21 @@ ssl3_get_client_kex_rsa(SSL *s, unsigned char *p, long n)
         if ((al == -1) && !((p[0] == (s->client_version >> 8)) &&
             (p[1] == (s->client_version & 0xff)))) {
                 /*
-                 * The premaster secret must contain the same version
-                 * number as the ClientHello to detect version rollback
-                 * attacks (strangely, the protocol does not offer such
-                 * protection for DH ciphersuites).
-                 * However, buggy clients exist that send the negotiated
-                 * protocol version instead if the server does not
-                 * support the requested protocol version.
-                 * If SSL_OP_TLS_ROLLBACK_BUG is set, tolerate such
-                 * clients.
+                 * The premaster secret must contain the same version number
+                 * as the ClientHello to detect version rollback attacks
+                 * (strangely, the protocol does not offer such protection for
+                 * DH ciphersuites).
+                 *
+                 * The Klima-Pokorny-Rosa extension of Bleichenbacher's attack
+                 * (http://eprint.iacr.org/2003/052/) exploits the version
+                 * number check as a "bad version oracle" -- an alert would
+                 * reveal that the plaintext corresponding to some ciphertext
+                 * made up by the adversary is properly formatted except that
+                 * the version number is wrong. To avoid such attacks, we should
+                 * treat this just like any other decryption error.
                  */
-                if (!((s->internal->options & SSL_OP_TLS_ROLLBACK_BUG) &&
-                    (p[0] == (s->version >> 8)) &&
-                    (p[1] == (s->version & 0xff)))) {
-                        al = SSL_AD_DECODE_ERROR;
-                        /* SSLerror(s, SSL_R_BAD_PROTOCOL_VERSION_NUMBER); */
-
-                        /*
-                         * The Klima-Pokorny-Rosa extension of
-                         * Bleichenbacher's attack
-                         * (http://eprint.iacr.org/2003/052/) exploits
-                         * the version number check as a "bad version
-                         * oracle" -- an alert would reveal that the
-                         * plaintext corresponding to some ciphertext
-                         * made up by the adversary is properly
-                         * formatted except that the version number is
-                         * wrong.
-                         * To avoid such attacks, we should treat this
-                         * just like any other decryption error.
-                         */
-                }
+                al = SSL_AD_DECODE_ERROR;
+                /* SSLerror(s, SSL_R_BAD_PROTOCOL_VERSION_NUMBER); */
         }
 
         if (al != -1) {