[openssl-commits] [openssl] master update

[Matt Caswell]

The branch master has been updated
       via  68a166285102a7cf5dadee763243ae575c5cee77 (commit)
      from  2d2846237364671670c4b9a8415ea957887e1797 (commit)


- Log -----------------------------------------------------------------
commit 68a166285102a7cf5dadee763243ae575c5cee77
Author: Matt Caswell <matt at openssl.org>
Date:   Wed Oct 7 15:20:47 2015 +0100

    Don't advance PACKET in ssl_check_for_safari
    
    The function ssl_check_for_safari fingerprints the incoming extensions
    to see whether it is one of the broken versions of safari. However it was
    failing to reset the PACKET back to the same position it started in, hence
    causing some extensions to be skipped incorrectly.
    
    Reviewed-by: Emilia Käsper <emilia at openssl.org>

-----------------------------------------------------------------------

Summary of changes:
 ssl/t1_lib.c | 23 +++++++++++++----------
 1 file changed, 13 insertions(+), 10 deletions(-)

diff --git a/ssl/t1_lib.c b/ssl/t1_lib.c
index 4975c10..f18f502 100644
--- a/ssl/t1_lib.c
+++ b/ssl/t1_lib.c
@@ -1815,10 +1815,11 @@ static int tls1_alpn_handle_client_hello(SSL *s, PACKET *pkt, int *al)
  * Sadly we cannot differentiate 10.6, 10.7 and 10.8.4 (which work), from
  * 10.8..10.8.3 (which don't work).
  */
-static void ssl_check_for_safari(SSL *s, PACKET *pkt)
+static void ssl_check_for_safari(SSL *s, const PACKET *pkt)
 {
     unsigned int type, size;
     unsigned char *eblock1, *eblock2;
+    PACKET tmppkt;
 
     static const unsigned char kSafariExtensionsBlock[] = {
         0x00, 0x0a,             /* elliptic_curves extension */
@@ -1846,10 +1847,12 @@ static void ssl_check_for_safari(SSL *s, PACKET *pkt)
         0x02, 0x03,             /* SHA-1/ECDSA */
     };
 
-    if (!PACKET_forward(pkt, 2)
-            || !PACKET_get_net_2(pkt, &type)
-            || !PACKET_get_net_2(pkt, &size)
-            || !PACKET_forward(pkt, size))
+    tmppkt = *pkt;
+
+    if (!PACKET_forward(&tmppkt, 2)
+            || !PACKET_get_net_2(&tmppkt, &type)
+            || !PACKET_get_net_2(&tmppkt, &size)
+            || !PACKET_forward(&tmppkt, size))
         return;
 
     if (type != TLSEXT_TYPE_server_name)
@@ -1859,9 +1862,9 @@ static void ssl_check_for_safari(SSL *s, PACKET *pkt)
         const size_t len1 = sizeof(kSafariExtensionsBlock);
         const size_t len2 = sizeof(kSafariTLS12ExtensionsBlock);
 
-        if (!PACKET_get_bytes(pkt, &eblock1, len1)
-                || !PACKET_get_bytes(pkt, &eblock2, len2)
-                || PACKET_remaining(pkt))
+        if (!PACKET_get_bytes(&tmppkt, &eblock1, len1)
+                || !PACKET_get_bytes(&tmppkt, &eblock2, len2)
+                || PACKET_remaining(&tmppkt))
             return;
         if (memcmp(eblock1, kSafariExtensionsBlock, len1) != 0)
             return;
@@ -1870,8 +1873,8 @@ static void ssl_check_for_safari(SSL *s, PACKET *pkt)
     } else {
         const size_t len = sizeof(kSafariExtensionsBlock);
 
-        if (!PACKET_get_bytes(pkt, &eblock1, len)
-                || PACKET_remaining(pkt))
+        if (!PACKET_get_bytes(&tmppkt, &eblock1, len)
+                || PACKET_remaining(&tmppkt))
             return;
         if (memcmp(eblock1, kSafariExtensionsBlock, len) != 0)
             return;