commit 905dd2425c53d11e291fdf088e7ab39c78792054
author Manuel Pégourié-Gonnard <mpg@elzevir.fr> Wed Oct 01 12:03:55 2014 +0200
committer Paul Bakker <p.j.bakker@polarssl.org> Tue Oct 21 16:32:43 2014 +0200
tree d673803fa429822a4c48bffb13e049551b2ee9e0
parent 0ac247fd88c8238ab780f6937e622c1def05e6e1

Add ssl_set_handshake_timeout()

include/polarssl/ssl.h

diff --git a/include/polarssl/ssl.h b/include/polarssl/ssl.h
index 60f32d7..9ff1d4f 100644
--- a/include/polarssl/ssl.h
+++ b/include/polarssl/ssl.h
@@ -831,6 +831,13 @@
     unsigned long time_limit;
 #endif
 
+#if defined(POLARSSL_SSL_PROTO_DTLS)
+    uint32_t hs_timeout_min;    /*!< initial value of the handshake
+                                     retransmission timeout             */
+    uint32_t hs_timeout_max;    /*!< maximum value of the handshake
+                                     retransmission timeout             */
+#endif
+
     /*
      * Record layer (incoming data)
      */
@@ -1286,6 +1293,25 @@
 void ssl_set_dtls_anti_replay( ssl_context *ssl, char mode );
 #endif /* POLARSSL_SSL_DTLS_ANTI_REPLAY */
 
+#if defined(POLARSSL_SSL_PROTO_DTLS)
+/**
+ * \brief          Set retransmit timeout values for the DTLS handshale.
+ *                 (DTLS only, no effect on TLS.)
+ *
+ * \param ssl      SSL context
+ * \param min      Initial timeout value in milliseconds.
+ *                 Default: 1000 (1 second).
+ * \param max      Maximum timeout value in milliseconds.
+ *                 Default: 60000 (60 seconds).
+ *
+ * \note           Default values are from RFC 6347 section 4.2.4.1.
+ *
+ * \note           Higher values for initial timeout may increase average
+ *                 handshake latency. Lower values may increase the risk of
+ *                 network congestion by causing more retransmissions.
+ */
+void ssl_set_handshake_timeout( ssl_context *ssl, uint32_t min, uint32_t max );
+#endif /* POLARSSL_SSL_PROTO_DTLS */
 
 /**
  * \brief          Set the session cache callbacks (server-side only)

library/ssl_tls.c

diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index 308d877..215f005 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -117,16 +117,16 @@
 {
     uint32_t new_timeout;
 
-    if( ssl->handshake->retransmit_timeout >= SSL_DTLS_TIMEOUT_DFL_MAX )
+    if( ssl->handshake->retransmit_timeout >= ssl->hs_timeout_max )
         return( -1 );
 
     new_timeout = 2 * ssl->handshake->retransmit_timeout;
 
     /* Avoid arithmetic overflow and range overflow */
     if( new_timeout < ssl->handshake->retransmit_timeout ||
-        new_timeout > SSL_DTLS_TIMEOUT_DFL_MAX )
+        new_timeout > ssl->hs_timeout_max )
     {
-        new_timeout = SSL_DTLS_TIMEOUT_DFL_MAX;
+        new_timeout = ssl->hs_timeout_max;
     }
 
     ssl->handshake->retransmit_timeout = new_timeout;
@@ -138,7 +138,7 @@
 
 static void ssl_reset_retransmit_timeout( ssl_context *ssl )
 {
-    ssl->handshake->retransmit_timeout = SSL_DTLS_TIMEOUT_DFL_MIN;
+    ssl->handshake->retransmit_timeout = ssl->hs_timeout_min;
     SSL_DEBUG_MSG( 3, ( "update timeout value to %d millisecs",
                         ssl->handshake->retransmit_timeout ) );
 }
@@ -4535,7 +4535,7 @@
 #if defined(POLARSSL_SSL_PROTO_DTLS)
     ssl->handshake->alt_transform_out = ssl->transform_out;
 
-    ssl->handshake->retransmit_timeout = SSL_DTLS_TIMEOUT_DFL_MIN;
+    ssl->handshake->retransmit_timeout = ssl->hs_timeout_min;
 
     if( ssl->endpoint == SSL_IS_CLIENT )
         ssl->handshake->retransmit_state = SSL_RETRANS_PREPARING;
@@ -4647,6 +4647,11 @@
     ssl->anti_replay = SSL_ANTI_REPLAY_ENABLED;
 #endif
 
+#if defined(POLARSSL_SSL_PROTO_DTLS)
+    ssl->hs_timeout_min = SSL_DTLS_TIMEOUT_DFL_MIN;
+    ssl->hs_timeout_max = SSL_DTLS_TIMEOUT_DFL_MAX;
+#endif
+
     if( ( ret = ssl_handshake_init( ssl ) ) != 0 )
         return( ret );
 
@@ -4871,6 +4876,14 @@
 }
 #endif
 
+#if defined(POLARSSL_SSL_PROTO_DTLS)
+void ssl_set_handshake_timeout( ssl_context *ssl, uint32_t min, uint32_t max )
+{
+    ssl->hs_timeout_min = min;
+    ssl->hs_timeout_max = max;
+}
+#endif
+
 void ssl_set_authmode( ssl_context *ssl, int authmode )
 {
     ssl->authmode   = authmode;