From 7bb7899121c20ff7e2ea920d3233bf1325acddc8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Manuel=20P=C3=A9gouri=C3=A9-Gonnard?= <mpg@elzevir.fr>
Date: Wed, 17 Jul 2013 13:50:08 +0200
Subject: [PATCH] Send max_fragment_length extension (server)

---
 library/ssl_srv.c | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/library/ssl_srv.c b/library/ssl_srv.c
index 7e1df64b1..2177253f3 100644
--- a/library/ssl_srv.c
+++ b/library/ssl_srv.c
@@ -987,6 +987,30 @@ static void ssl_write_renegotiation_ext( ssl_context *ssl,
     *olen = 5 + ssl->verify_data_len * 2;
 }
 
+static void ssl_write_max_fragment_length_ext( ssl_context *ssl,
+                                               unsigned char *buf,
+                                               size_t *olen )
+{
+    unsigned char *p = buf;
+
+    if( ssl->mfl_code == SSL_MAX_FRAG_LEN_NONE ) {
+        *olen = 0;
+        return;
+    }
+
+    SSL_DEBUG_MSG( 3, ( "server hello, max_fragment_length extension" ) );
+
+    *p++ = (unsigned char)( ( TLS_EXT_MAX_FRAGMENT_LENGTH >> 8 ) & 0xFF );
+    *p++ = (unsigned char)( ( TLS_EXT_MAX_FRAGMENT_LENGTH      ) & 0xFF );
+
+    *p++ = 0x00;
+    *p++ = 1;
+
+    *p++ = ssl->mfl_code;
+
+    *olen = 5;
+}
+
 static int ssl_write_server_hello( ssl_context *ssl )
 {
 #if defined(POLARSSL_HAVE_TIME)
@@ -1101,6 +1125,9 @@ static int ssl_write_server_hello( ssl_context *ssl )
     ssl_write_renegotiation_ext( ssl, p + 2 + ext_len, &olen );
     ext_len += olen;
 
+    ssl_write_max_fragment_length_ext( ssl, p + 2 + ext_len, &olen );
+    ext_len += olen;
+
     SSL_DEBUG_MSG( 3, ( "server hello, total extension length: %d", ext_len ) );
 
     *p++ = (unsigned char)( ( ext_len >> 8 ) & 0xFF );