socket: disallow CBC cipher modes

This is related to CVE-2014-3566 a.k.a. POODLE.

	http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2014-3566

POODLE is specific to CBC cipher modes in SSLv3.  Because there is no
way to prevent SSLv3 fallback on a system with an unpatched version of
OpenSSL, users of such systems can only be protected by disallowing CBC
modes.  The default cipher-mode specification in our code has been
changed accordingly.  Users can still set their own cipher modes if they
wish.  To support them, the ssl-authz.t test script provides an example
of how to combine the CBC exclusion with other criteria in a script.

Change-Id: Ib1fa547082fbb7de9df94ffd182b1800d6e354e5
BUG: 1155328
Signed-off-by: Jeff Darcy <jdarcy@redhat.com>
Reviewed-on: http://review.gluster.org/8962
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Kaleb KEITHLEY <kkeithle@redhat.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>

2 files changed, 84 insertions, 1 deletions

diff --git a/rpc/rpc-transport/socket/src/socket.c b/rpc/rpc-transport/socket/src/socket.c
index cec0825f7d4..c4b777bca34 100644
--- a/rpc/rpc-transport/socket/src/socket.c
+++ b/rpc/rpc-transport/socket/src/socket.c
@@ -45,6 +45,72 @@
 #define SSL_CA_LIST_OPT     "transport.socket.ssl-ca-list"
 #define OWN_THREAD_OPT      "transport.socket.own-thread"
 
+/*
+ * This list was derived by taking the cipher list "HIGH:!SSLv2" (the previous
+ * default) and excluding CBC entries to mitigate the "POODLE" attack.  It
+ * should be re-evaluated in light of each future vulnerability, as those are
+ * discovered.
+ */
+static char *default_cipher_list =
+        "ECDHE-RSA-AES256-GCM-SHA384:"
+        "ECDHE-ECDSA-AES256-GCM-SHA384:"
+        "ECDHE-RSA-AES256-SHA384:"
+        "ECDHE-ECDSA-AES256-SHA384:"
+        "ECDHE-RSA-AES256-SHA:"
+        "ECDHE-ECDSA-AES256-SHA:"
+        "DHE-DSS-AES256-GCM-SHA384:"
+        "DHE-RSA-AES256-GCM-SHA384:"
+        "DHE-RSA-AES256-SHA256:"
+        "DHE-DSS-AES256-SHA256:"
+        "DHE-RSA-AES256-SHA:"
+        "DHE-DSS-AES256-SHA:"
+        "DHE-RSA-CAMELLIA256-SHA:"
+        "DHE-DSS-CAMELLIA256-SHA:"
+        "AECDH-AES256-SHA:"
+        "ADH-AES256-GCM-SHA384:"
+        "ADH-AES256-SHA256:"
+        "ADH-AES256-SHA:"
+        "ADH-CAMELLIA256-SHA:"
+        "ECDH-RSA-AES256-GCM-SHA384:"
+        "ECDH-ECDSA-AES256-GCM-SHA384:"
+        "ECDH-RSA-AES256-SHA384:"
+        "ECDH-ECDSA-AES256-SHA384:"
+        "ECDH-RSA-AES256-SHA:"
+        "ECDH-ECDSA-AES256-SHA:"
+        "AES256-GCM-SHA384:"
+        "AES256-SHA256:"
+        "AES256-SHA:"
+        "CAMELLIA256-SHA:"
+        "ECDHE-RSA-AES128-GCM-SHA256:"
+        "ECDHE-ECDSA-AES128-GCM-SHA256:"
+        "ECDHE-RSA-AES128-SHA256:"
+        "ECDHE-ECDSA-AES128-SHA256:"
+        "ECDHE-RSA-AES128-SHA:"
+        "ECDHE-ECDSA-AES128-SHA:"
+        "DHE-DSS-AES128-GCM-SHA256:"
+        "DHE-RSA-AES128-GCM-SHA256:"
+        "DHE-RSA-AES128-SHA256:"
+        "DHE-DSS-AES128-SHA256:"
+        "DHE-RSA-AES128-SHA:"
+        "DHE-DSS-AES128-SHA:"
+        "DHE-RSA-CAMELLIA128-SHA:"
+        "DHE-DSS-CAMELLIA128-SHA:"
+        "AECDH-AES128-SHA:"
+        "ADH-AES128-GCM-SHA256:"
+        "ADH-AES128-SHA256:"
+        "ADH-AES128-SHA:"
+        "ADH-CAMELLIA128-SHA:"
+        "ECDH-RSA-AES128-GCM-SHA256:"
+        "ECDH-ECDSA-AES128-GCM-SHA256:"
+        "ECDH-RSA-AES128-SHA256:"
+        "ECDH-ECDSA-AES128-SHA256:"
+        "ECDH-RSA-AES128-SHA:"
+        "ECDH-ECDSA-AES128-SHA:"
+        "AES128-GCM-SHA256:"
+        "AES128-SHA256:"
+        "AES128-SHA:"
+        "CAMELLIA128-SHA";      /* no colon for last entry */
+
 /* TBD: do automake substitutions etc. (ick) to set these. */
 #if !defined(DEFAULT_ETC_SSL)
 #  ifdef GF_LINUX_HOST_OS
@@ -3560,7 +3626,7 @@ socket_init (rpc_transport_t *this)
         uint32_t          backlog = 0;
 	int               session_id = 0;
         int32_t           cert_depth = 1;
-        char             *cipher_list = "HIGH:-SSLv2";
+        char             *cipher_list = default_cipher_list;
         int               ret;
 
         if (this->private) {
diff --git a/tests/features/ssl-authz.t b/tests/features/ssl-authz.t
index 72db389f5cf..efaa47c6d40 100755
--- a/tests/features/ssl-authz.t
+++ b/tests/features/ssl-authz.t
@@ -25,6 +25,22 @@ TEST glusterd
 TEST pidof glusterd
 TEST $CLI volume info;
 
+# Construct a cipher list that excludes CBC because of POODLE.
+# http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2014-3566
+#
+# Since this is a bit opaque, here's what it does:
+#	(1) Get the ciphers matching a normal cipher-list spec
+#	(2) Delete any colon-separated entries containing "CBC"
+#	(3) Collapse adjacent colons from deleted entries
+#	(4) Remove colons at the beginning or end
+function valid_ciphers {
+	openssl ciphers 'HIGH:!SSLv2' | sed	\
+		-e '/[^:]*CBC[^:]*/s///g'	\
+		-e '/::*/s//:/g'		\
+		-e '/^:/s///'			\
+		-e '/:$/s///'
+}
+
 TEST openssl genrsa -out $SSL_KEY 1024
 TEST openssl req -new -x509 -key $SSL_KEY -subj /CN=Anyone -out $SSL_CERT
 ln $SSL_CERT $SSL_CA
@@ -32,6 +48,7 @@ ln $SSL_CERT $SSL_CA
 TEST $CLI volume create $V0 $H0:$B0/1
 TEST $CLI volume set $V0 server.ssl on
 TEST $CLI volume set $V0 client.ssl on
+#EST $CLI volume set $V0 ssl.cipher-list $(valid_ciphers)
 TEST $CLI volume set $V0 auth.ssl-allow Anyone
 TEST $CLI volume start $V0