From d106cfc16db3a30d9212a3f37e386053cd1c26de Mon Sep 17 00:00:00 2001
From: delphij <delphij@ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f>
Date: Sat, 30 Jan 2016 06:12:03 +0000
Subject: [PATCH] Fix OpenSSL SSLv2 ciphersuite downgrade vulnerability.

Security:	CVE-2015-3197
Security:	FreeBSD-SA-16:11.openssl
Approved by:	so


git-svn-id: svn://svn.freebsd.org/base/releng/9.3@295061 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f
---
 UPDATING                     |  4 ++++
 crypto/openssl/ssl/s2_srvr.c | 17 ++++++++++++++---
 sys/conf/newvers.sh          |  2 +-
 3 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/UPDATING b/UPDATING
index 33bc0b796..cd46329cf 100644
--- a/UPDATING
+++ b/UPDATING
@@ -11,6 +11,10 @@ handbook:
 Items affecting the ports and packages system can be found in
 /usr/ports/UPDATING.  Please read that file before running portupgrade.
 
+20160130	p36	FreeBSD-SA-16:11.openssl
+
+	Fix OpenSSL SSLv2 ciphersuite downgrade vulnerability. [SA-16:11]
+
 20160127	p35	FreeBSD-SA-16:08.bind
 			FreeBSD-SA-16:09.ntp
 			FreeBSD-SA-16:10.linux
diff --git a/crypto/openssl/ssl/s2_srvr.c b/crypto/openssl/ssl/s2_srvr.c
index 72cc812d7..95cf16be7 100644
--- a/crypto/openssl/ssl/s2_srvr.c
+++ b/crypto/openssl/ssl/s2_srvr.c
@@ -392,7 +392,7 @@ static int get_client_master_key(SSL *s)
 			}
 
 		cp=ssl2_get_cipher_by_char(p);
-		if (cp == NULL)
+		if (cp == NULL || sk_SSL_CIPHER_find(s->session->ciphers, cp) < 0)
 			{
 			ssl2_return_error(s,SSL2_PE_NO_CIPHER);
 			SSLerr(SSL_F_GET_CLIENT_MASTER_KEY, SSL_R_NO_CIPHER_MATCH);
@@ -690,9 +690,12 @@ static int get_client_hello(SSL *s)
 		    prio = cs;
 		    allow = cl;
 		    }
-		for (z=0; z<sk_SSL_CIPHER_num(prio); z++)
+		/* Generate list of SSLv2 ciphers shared between client and server */
+		for (z = 0; z < sk_SSL_CIPHER_num(prio); z++)
 			{
-			if (sk_SSL_CIPHER_find(allow,sk_SSL_CIPHER_value(prio,z)) < 0)
+			const SSL_CIPHER *cp = sk_SSL_CIPHER_value(prio, z);
+			if ((cp->algorithms & SSL_SSLV2) == 0 ||
+			    sk_SSL_CIPHER_find(allow, cp) < 0)
 				{
 				(void)sk_SSL_CIPHER_delete(prio,z);
 				z--;
@@ -703,6 +706,14 @@ static int get_client_hello(SSL *s)
 		    sk_SSL_CIPHER_free(s->session->ciphers);
 		    s->session->ciphers = prio;
 		    }
+
+		/* Make sure we have at least one cipher in common */
+		if (sk_SSL_CIPHER_num(s->session->ciphers) == 0)
+			{
+			ssl2_return_error(s, SSL2_PE_NO_CIPHER);
+			SSLerr(SSL_F_GET_CLIENT_HELLO, SSL_R_NO_CIPHER_MATCH);
+			return -1;
+			}
 		/* s->session->ciphers should now have a list of
 		 * ciphers that are on both the client and server.
 		 * This list is ordered by the order the client sent
diff --git a/sys/conf/newvers.sh b/sys/conf/newvers.sh
index 49ad94fd3..2800d8a46 100644
--- a/sys/conf/newvers.sh
+++ b/sys/conf/newvers.sh
@@ -32,7 +32,7 @@
 
 TYPE="FreeBSD"
 REVISION="9.3"
-BRANCH="RELEASE-p35"
+BRANCH="RELEASE-p36"
 if [ "X${BRANCH_OVERRIDE}" != "X" ]; then
 	BRANCH=${BRANCH_OVERRIDE}
 fi
-- 
2.45.0