Add ssl_set_session_tickets()
diff --git a/include/polarssl/ssl.h b/include/polarssl/ssl.h
index a25ebea..5596cc1 100644
--- a/include/polarssl/ssl.h
+++ b/include/polarssl/ssl.h
@@ -154,6 +154,9 @@
 #define SSL_TRUNC_HMAC_ENABLED          1
 #define SSL_TRUNCATED_HMAC_LEN          10  /* 80 bits, rfc 6066 section 7 */
 
+#define SSL_SESSION_TICKETS_DISABLED     0
+#define SSL_SESSION_TICKETS_ENABLED      1
+
 /*
  * Size of the input / output buffer.
  * Note: the RFC defines the default size of SSL / TLS messages. If you
@@ -561,6 +564,7 @@
     int allow_legacy_renegotiation;     /*!<  allow legacy renegotiation     */
     const int *ciphersuite_list[4];     /*!<  allowed ciphersuites / version */
     int trunc_hmac;                     /*!<  negotiate truncated hmac?      */
+    int session_tickets;                /*!<  use session tickets?    */
 
 #if defined(POLARSSL_DHM_C)
     mpi dhm_P;                          /*!<  prime modulus for DHM   */
@@ -667,6 +671,9 @@
  *
  * \param ssl      SSL context
  * \param endpoint must be SSL_IS_CLIENT or SSL_IS_SERVER
+ *
+ * \note           This function should be called right after ssl_init() since
+ *                 some other ssl_set_foo() functions depend on it.
  */
 void ssl_set_endpoint( ssl_context *ssl, int endpoint );
 
@@ -1013,6 +1020,24 @@
 int ssl_set_truncated_hmac( ssl_context *ssl, int truncate );
 
 /**
+ * \brief          Enable / Disable session tickets
+ *                 (Default: SSL_SESSION_TICKETS_ENABLED on client,
+ *                           SSL_SESSION_TICKETS_DISABLED on server)
+ *
+ * \note           On server, ssl_set_rng() must be called before this function
+ *                 to allow generating the ticket encryption and
+ *                 authentication keys.
+ *
+ * \param ssl      SSL context
+ * \param use_tickets   Enable or disable (SSL_SESSION_TICKETS_ENABLED or
+ *                                         SSL_SESSION_TICKETS_DISABLED)
+ *
+ * \return         O if successful,
+ *                 or a specific error code (server only).
+ */
+int ssl_set_session_tickets( ssl_context *ssl, int use_tickets );
+
+/**
  * \brief          Enable / Disable renegotiation support for connection when
  *                 initiated by peer
  *                 (Default: SSL_RENEGOTIATION_DISABLED)
diff --git a/library/ssl_cli.c b/library/ssl_cli.c
index 40b9f23..402c85a 100644
--- a/library/ssl_cli.c
+++ b/library/ssl_cli.c
@@ -328,6 +328,12 @@
     unsigned char *p = buf;
     size_t tlen = ssl->session_negotiate->ticket_len;
 
+    if( ssl->session_tickets == SSL_SESSION_TICKETS_DISABLED )
+    {
+        *olen = 0;
+        return;
+    }
+
     SSL_DEBUG_MSG( 3, ( "client hello, adding session ticket extension" ) );
 
     *p++ = (unsigned char)( ( TLS_EXT_SESSION_TICKET >> 8 ) & 0xFF );
@@ -648,8 +654,11 @@
                                          const unsigned char *buf,
                                          size_t len )
 {
-    if( len != 0 )
+    if( ssl->session_tickets == SSL_SESSION_TICKETS_DISABLED ||
+        len != 0 )
+    {
         return( POLARSSL_ERR_SSL_BAD_HS_SERVER_HELLO );
+    }
 
     ((void) buf);
 
diff --git a/library/ssl_srv.c b/library/ssl_srv.c
index ad9142c..5b7db17 100644
--- a/library/ssl_srv.c
+++ b/library/ssl_srv.c
@@ -534,6 +534,9 @@
                                          const unsigned char *buf,
                                          size_t len )
 {
+    if( ssl->session_tickets == SSL_SESSION_TICKETS_DISABLED )
+        return( 0 );
+
     /* Remember the client asked us to send a new ticket */
     ssl->handshake->new_session_ticket = 1;
 
diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index db87fe0..f7b9bd9 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -2978,6 +2978,9 @@
 void ssl_set_endpoint( ssl_context *ssl, int endpoint )
 {
     ssl->endpoint   = endpoint;
+
+    if( endpoint == SSL_IS_CLIENT )
+        ssl->session_tickets = SSL_SESSION_TICKETS_ENABLED;
 }
 
 void ssl_set_authmode( ssl_context *ssl, int authmode )
@@ -3225,6 +3228,13 @@
     ssl->allow_legacy_renegotiation = allow_legacy;
 }
 
+int ssl_set_session_tickets( ssl_context *ssl, int use_tickets )
+{
+    ssl->session_tickets = use_tickets;
+
+    return( 0 );
+}
+
 /*
  * SSL get accessors
  */
diff --git a/programs/ssl/ssl_client2.c b/programs/ssl/ssl_client2.c
index d57ed07..4b92c19 100644
--- a/programs/ssl/ssl_client2.c
+++ b/programs/ssl/ssl_client2.c
@@ -60,6 +60,7 @@
 #define DFL_MFL_CODE            SSL_MAX_FRAG_LEN_NONE
 #define DFL_TRUNC_HMAC          0
 #define DFL_RECONNECT           0
+#define DFL_TICKETS             SSL_SESSION_TICKETS_ENABLED
 
 #define LONG_HEADER "User-agent: blah-blah-blah-blah-blah-blah-blah-blah-"   \
     "-01--blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-" \
@@ -98,6 +99,7 @@
     unsigned char mfl_code;     /* code for maximum fragment length         */
     int trunc_hmac;             /* negotiate truncated hmac or not          */
     int reconnect;              /* attempt to resume session                */
+    int tickets;                /* enable / disable session tickets         */
 } opt;
 
 static void my_debug( void *ctx, int level, const char *str )
@@ -187,6 +189,7 @@
     "    renegotiation=%%d    default: 1 (enabled)\n"       \
     "    allow_legacy=%%d     default: 0 (disabled)\n"      \
     "    reconnect=%%d        default: 0 (disabled)\n"      \
+    "    tickets=%%d          default: 1 (enabled)\n"       \
     "\n"                                                    \
     "    min_version=%%s      default: \"\" (ssl3)\n"       \
     "    max_version=%%s      default: \"\" (tls1_2)\n"     \
@@ -291,6 +294,7 @@
     opt.mfl_code            = DFL_MFL_CODE;
     opt.trunc_hmac          = DFL_TRUNC_HMAC;
     opt.reconnect           = DFL_RECONNECT;
+    opt.tickets             = DFL_TICKETS;
 
     for( i = 1; i < argc; i++ )
     {
@@ -357,6 +361,12 @@
             if( opt.reconnect < 0 || opt.reconnect > 2 )
                 goto usage;
         }
+        else if( strcmp( p, "tickets" ) == 0 )
+        {
+            opt.tickets = atoi( q );
+            if( opt.tickets < 0 || opt.tickets > 2 )
+                goto usage;
+        }
         else if( strcmp( p, "min_version" ) == 0 )
         {
             if( strcmp( q, "ssl3" ) == 0 )
@@ -664,6 +674,8 @@
     ssl_set_bio( &ssl, net_recv, &server_fd,
                        net_send, &server_fd );
 
+    ssl_set_session_tickets( &ssl, opt.tickets );
+
     if( opt.force_ciphersuite[0] != DFL_FORCE_CIPHER )
         ssl_set_ciphersuites( &ssl, opt.force_ciphersuite );
 
diff --git a/programs/ssl/ssl_server2.c b/programs/ssl/ssl_server2.c
index 57ff85c..2ed74e4 100644
--- a/programs/ssl/ssl_server2.c
+++ b/programs/ssl/ssl_server2.c
@@ -69,6 +69,7 @@
 #define DFL_MAX_VERSION         -1
 #define DFL_AUTH_MODE           SSL_VERIFY_OPTIONAL
 #define DFL_MFL_CODE            SSL_MAX_FRAG_LEN_NONE
+#define DFL_TICKETS             SSL_SESSION_TICKETS_ENABLED
 
 #define LONG_RESPONSE "<p>01-blah-blah-blah-blah-blah-blah-blah-blah-blah\r\n" \
     "02-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah\r\n"  \
@@ -105,6 +106,7 @@
     int max_version;            /* maximum protocol version accepted        */
     int auth_mode;              /* verify mode for connection               */
     unsigned char mfl_code;     /* code for maximum fragment length         */
+    int tickets;                /* enable / disable session tickets         */
 } opt;
 
 static void my_debug( void *ctx, int level, const char *str )
@@ -152,6 +154,7 @@
     USAGE_IO                                                \
     "    request_page=%%s     default: \".\"\n"             \
     "    renegotiation=%%d    default: 1 (enabled)\n"       \
+    "    tickets=%%d          default: 1 (enabled)\n"       \
     "    allow_legacy=%%d     default: 0 (disabled)\n"      \
     "    min_version=%%s      default: \"ssl3\"\n"          \
     "    max_version=%%s      default: \"tls1_2\"\n"        \
@@ -265,6 +268,7 @@
     opt.max_version         = DFL_MAX_VERSION;
     opt.auth_mode           = DFL_AUTH_MODE;
     opt.mfl_code            = DFL_MFL_CODE;
+    opt.tickets             = DFL_TICKETS;
 
     for( i = 1; i < argc; i++ )
     {
@@ -396,6 +400,12 @@
             else
                 goto usage;
         }
+        else if( strcmp( p, "tickets" ) == 0 )
+        {
+            opt.tickets = atoi( q );
+            if( opt.tickets < 0 || opt.tickets > 1 )
+                goto usage;
+        }
         else
             goto usage;
     }
@@ -611,6 +621,8 @@
                                  ssl_cache_set, &cache );
 #endif
 
+    ssl_set_session_tickets( &ssl, opt.tickets );
+
     if( opt.force_ciphersuite[0] != DFL_FORCE_CIPHER )
         ssl_set_ciphersuites( &ssl, opt.force_ciphersuite );