From 8b46459ae540c32e60c12a9346c60dac3b8e0132 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Manuel=20P=C3=A9gouri=C3=A9-Gonnard?= <mpg@elzevir.fr>
Date: Tue, 16 Jul 2013 12:45:26 +0200
Subject: [PATCH 01/16] Add ssl_set_max_frag_len()

---
 include/polarssl/ssl.h | 28 ++++++++++++++++++++++++++++
 library/ssl_tls.c      | 32 ++++++++++++++++++++++++++++++++
 2 files changed, 60 insertions(+)

diff --git a/include/polarssl/ssl.h b/include/polarssl/ssl.h
index eca6879e3..9bb0c4438 100644
--- a/include/polarssl/ssl.h
+++ b/include/polarssl/ssl.h
@@ -117,6 +117,13 @@
 #define SSL_MINOR_VERSION_2             2   /*!< TLS v1.1 */
 #define SSL_MINOR_VERSION_3             3   /*!< TLS v1.2 */
 
+/* RFC 6066 section 4 */
+#define SSL_MAX_FRAG_LEN_NONE           0   /*!< don't use this extension   */
+#define SSL_MAX_FRAG_LEN_512            1   /*!< MaxFragmentLength 2^9      */
+#define SSL_MAX_FRAG_LEN_1024           2   /*!< MaxFragmentLength 2^10     */
+#define SSL_MAX_FRAG_LEN_2048           3   /*!< MaxFragmentLength 2^11     */
+#define SSL_MAX_FRAG_LEN_4096           4   /*!< MaxFragmentLength 2^12     */
+
 #define SSL_IS_CLIENT                   0
 #define SSL_IS_SERVER                   1
 #define SSL_COMPRESS_NULL               0
@@ -498,6 +505,10 @@ struct _ssl_context
     size_t out_msglen;          /*!< record header: message length    */
     size_t out_left;            /*!< amount of data not yet written   */
 
+    /* Maximum fragment length extension (RFC 6066 section 4) */
+    unsigned char mfl_code;     /*!< numerical code for MaxFragmentLength   */
+    uint16_t max_frag_len;      /*!< value of MaxFragmentLength             */
+
     /*
      * PKI layer
      */
@@ -944,6 +955,23 @@ void ssl_set_max_version( ssl_context *ssl, int major, int minor );
  */
 void ssl_set_min_version( ssl_context *ssl, int major, int minor );
 
+/**
+ * \brief          Set the maximum fragment length to emit and/or negotiate
+ *                 (Default: SSL_MAX_CONTENT_LEN, usually 2^14 bytes)
+ *                 (Server: set maximum fragment length to emit,
+ *                 usually negotiated by the client during handshake
+ *                 (Client: set maximum fragment length to emit *and*
+ *                 negotiate with the server during handshake)
+ *
+ * \param ssl      SSL context
+ * \param mfl      Code for maximum fragment length (allowed values:
+ *                 SSL_MAX_FRAG_LEN_512,  SSL_MAX_FRAG_LEN_1024,
+ *                 SSL_MAX_FRAG_LEN_2048, SSL_MAX_FRAG_LEN_4096)
+ *
+ * \return         O if successful or POLARSSL_ERR_SSL_BAD_INPUT_DATA
+ */
+int ssl_set_max_frag_len( ssl_context *ssl, unsigned char mfl_code );
+
 /**
  * \brief          Enable / Disable renegotiation support for connection when
  *                 initiated by peer
diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index dfeed3377..b6bb44f78 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -2826,6 +2826,9 @@ int ssl_init( ssl_context *ssl )
     memset( ssl-> in_ctr, 0, SSL_BUFFER_LEN );
     memset( ssl->out_ctr, 0, SSL_BUFFER_LEN );
 
+    ssl->mfl_code = SSL_MAX_FRAG_LEN_NONE;
+    ssl->max_frag_len = SSL_MAX_CONTENT_LEN;
+
     ssl->hostname = NULL;
     ssl->hostname_len = 0;
 
@@ -3111,6 +3114,35 @@ void ssl_set_min_version( ssl_context *ssl, int major, int minor )
     ssl->min_minor_ver = minor;
 }
 
+int ssl_set_max_frag_len( ssl_context *ssl, unsigned char mfl_code )
+{
+    switch( mfl_code )
+    {
+        case SSL_MAX_FRAG_LEN_512:
+            ssl->max_frag_len = 512;
+            break;
+
+        case SSL_MAX_FRAG_LEN_1024:
+            ssl->max_frag_len = 1024;
+            break;
+
+        case SSL_MAX_FRAG_LEN_2048:
+            ssl->max_frag_len = 2048;
+            break;
+
+        case SSL_MAX_FRAG_LEN_4096:
+            ssl->max_frag_len = 4096;
+            break;
+
+        default:
+            return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
+    }
+
+    ssl->mfl_code = mfl_code;
+
+    return( 0 );
+}
+
 void ssl_set_renegotiation( ssl_context *ssl, int renegotiation )
 {
     ssl->disable_renegotiation = renegotiation;

From 0df6b1f068c0b9d61666b2272e405d42f232b4cb Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Manuel=20P=C3=A9gouri=C3=A9-Gonnard?= <mpg@elzevir.fr>
Date: Tue, 16 Jul 2013 13:39:57 +0200
Subject: [PATCH 02/16] ssl_client2: add max_frag_len option

---
 programs/ssl/ssl_client2.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/programs/ssl/ssl_client2.c b/programs/ssl/ssl_client2.c
index 036cc67ae..63c1b66fd 100644
--- a/programs/ssl/ssl_client2.c
+++ b/programs/ssl/ssl_client2.c
@@ -57,6 +57,7 @@
 #define DFL_MIN_VERSION         -1
 #define DFL_MAX_VERSION         -1
 #define DFL_AUTH_MODE           SSL_VERIFY_OPTIONAL
+#define DFL_MFL_CODE            SSL_MAX_FRAG_LEN_NONE
 
 #define GET_REQUEST "GET %s HTTP/1.0\r\n\r\n"
 
@@ -81,6 +82,7 @@ struct options
     int min_version;            /* minimum protocol version accepted        */
     int max_version;            /* maximum protocol version accepted        */
     int auth_mode;              /* verify mode for connection               */
+    unsigned char mfl_code;     /* code for maximum fragment length         */
 } opt;
 
 static void my_debug( void *ctx, int level, const char *str )
@@ -176,6 +178,8 @@ static int my_verify( void *data, x509_cert *crt, int depth, int *flags )
     "                        options: ssl3, tls1, tls1_1, tls1_2\n" \
     "    auth_mode=%%s        default: \"optional\"\n"          \
     "                        options: none, optional, required\n" \
+    "    max_frag_len=%%d     default: 16384 (tls default)" \
+    "                        options: 512, 1024, 2048, 4096" \
     USAGE_PSK                                               \
     "\n"                                                    \
     "    force_ciphersuite=<name>    default: all enabled\n"\
@@ -265,6 +269,7 @@ int main( int argc, char *argv[] )
     opt.min_version         = DFL_MIN_VERSION;
     opt.max_version         = DFL_MAX_VERSION;
     opt.auth_mode           = DFL_AUTH_MODE;
+    opt.mfl_code            = DFL_MFL_CODE;
 
     for( i = 1; i < argc; i++ )
     {
@@ -387,6 +392,19 @@ int main( int argc, char *argv[] )
             else
                 goto usage;
         }
+        else if( strcmp( p, "max_frag_len" ) == 0 )
+        {
+            if( strcmp( q, "512" ) == 0 )
+                opt.mfl_code = SSL_MAX_FRAG_LEN_512;
+            else if( strcmp( q, "1024" ) == 0 )
+                opt.mfl_code = SSL_MAX_FRAG_LEN_1024;
+            else if( strcmp( q, "2048" ) == 0 )
+                opt.mfl_code = SSL_MAX_FRAG_LEN_2048;
+            else if( strcmp( q, "4096" ) == 0 )
+                opt.mfl_code = SSL_MAX_FRAG_LEN_4096;
+            else
+                goto usage;
+        }
         else
             goto usage;
     }
@@ -592,6 +610,8 @@ int main( int argc, char *argv[] )
     ssl_set_endpoint( &ssl, SSL_IS_CLIENT );
     ssl_set_authmode( &ssl, opt.auth_mode );
 
+    ssl_set_max_frag_len( &ssl, opt.mfl_code );
+
     ssl_set_rng( &ssl, ctr_drbg_random, &ctr_drbg );
     ssl_set_dbg( &ssl, my_debug, stdout );
     ssl_set_bio( &ssl, net_recv, &server_fd,

From 787b658bb34200860d224ae7f301dac2917a19c7 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Manuel=20P=C3=A9gouri=C3=A9-Gonnard?= <mpg@elzevir.fr>
Date: Tue, 16 Jul 2013 15:43:17 +0200
Subject: [PATCH 03/16] Implement max_frag_len write restriction

---
 library/ssl_tls.c          |  4 ++--
 programs/ssl/ssl_client2.c | 22 ++++++++++++++--------
 2 files changed, 16 insertions(+), 10 deletions(-)

diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index b6bb44f78..b2d3dc85a 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -3416,8 +3416,8 @@ int ssl_write( ssl_context *ssl, const unsigned char *buf, size_t len )
         }
     }
 
-    n = ( len < SSL_MAX_CONTENT_LEN )
-        ? len : SSL_MAX_CONTENT_LEN;
+    n = ( len < ssl->max_frag_len )
+        ? len : ssl->max_frag_len;
 
     if( ssl->out_left != 0 )
     {
diff --git a/programs/ssl/ssl_client2.c b/programs/ssl/ssl_client2.c
index 63c1b66fd..0a7048120 100644
--- a/programs/ssl/ssl_client2.c
+++ b/programs/ssl/ssl_client2.c
@@ -59,7 +59,10 @@
 #define DFL_AUTH_MODE           SSL_VERIFY_OPTIONAL
 #define DFL_MFL_CODE            SSL_MAX_FRAG_LEN_NONE
 
-#define GET_REQUEST "GET %s HTTP/1.0\r\n\r\n"
+/* Uncomment to test sending long paquets */
+#define LONG_HEADER // "User-agent: blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-END\r\n"
+
+#define GET_REQUEST "GET %s HTTP/1.0\r\n" LONG_HEADER "\r\n"
 
 /*
  * global options
@@ -201,7 +204,7 @@ int main( int argc, char *argv[] )
 #else
 int main( int argc, char *argv[] )
 {
-    int ret = 0, len, server_fd, i;
+    int ret = 0, len, server_fd, i, written;
     unsigned char buf[1024];
 #if defined(POLARSSL_KEY_EXCHANGE_PSK_ENABLED)
     unsigned char psk[256];
@@ -702,17 +705,20 @@ int main( int argc, char *argv[] )
 
     len = sprintf( (char *) buf, GET_REQUEST, opt.request_page );
 
-    while( ( ret = ssl_write( &ssl, buf, len ) ) <= 0 )
+    for( written = 0; written < len; written += ret )
     {
-        if( ret != POLARSSL_ERR_NET_WANT_READ && ret != POLARSSL_ERR_NET_WANT_WRITE )
+        while( ( ret = ssl_write( &ssl, buf + written, len - written ) ) <= 0 )
         {
-            printf( " failed\n  ! ssl_write returned -0x%x\n\n", -ret );
-            goto exit;
+            if( ret != POLARSSL_ERR_NET_WANT_READ && ret != POLARSSL_ERR_NET_WANT_WRITE )
+            {
+                printf( " failed\n  ! ssl_write returned -0x%x\n\n", -ret );
+                goto exit;
+            }
         }
     }
 
-    len = ret;
-    printf( " %d bytes written\n\n%s", len, (char *) buf );
+    buf[written] = '\0';
+    printf( " %d bytes written\n\n%s\n", written, (char *) buf );
 
     /*
      * 7. Read the HTTP response

From 48f8d0dbbd6d86aa16d0df785da163d9fde0a2e5 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 10:25:37 +0200
Subject: [PATCH 04/16] Read max_fragment_length extension (server)

---
 include/polarssl/ssl.h |  2 ++
 library/ssl_srv.c      | 24 ++++++++++++++++++++++++
 2 files changed, 26 insertions(+)

diff --git a/include/polarssl/ssl.h b/include/polarssl/ssl.h
index 9bb0c4438..24e60f793 100644
--- a/include/polarssl/ssl.h
+++ b/include/polarssl/ssl.h
@@ -247,6 +247,8 @@
 #define TLS_EXT_SERVERNAME                   0
 #define TLS_EXT_SERVERNAME_HOSTNAME          0
 
+#define TLS_EXT_MAX_FRAGMENT_LENGTH          1
+
 #define TLS_EXT_SUPPORTED_ELLIPTIC_CURVES   10
 #define TLS_EXT_SUPPORTED_POINT_FORMATS     11
 
diff --git a/library/ssl_srv.c b/library/ssl_srv.c
index 2aef9c415..0e3225101 100644
--- a/library/ssl_srv.c
+++ b/library/ssl_srv.c
@@ -291,6 +291,22 @@ static int ssl_parse_supported_point_formats( ssl_context *ssl,
 }
 #endif /* POLARSSL_ECP_C */
 
+static int ssl_parse_max_fragment_length_ext( ssl_context *ssl,
+                                              const unsigned char *buf,
+                                              size_t len )
+{
+    int ret;
+
+    if( len != 1 ||
+        ( ret = ssl_set_max_frag_len( ssl, buf[0] ) ) != 0 )
+    {
+        SSL_DEBUG_MSG( 1, ( "bad client hello message" ) );
+        return( POLARSSL_ERR_SSL_BAD_HS_CLIENT_HELLO );
+    }
+
+    return( 0 );
+}
+
 #if defined(POLARSSL_SSL_SRV_SUPPORT_SSLV2_CLIENT_HELLO)
 static int ssl_parse_client_hello_v2( ssl_context *ssl )
 {
@@ -825,6 +841,14 @@ static int ssl_parse_client_hello( ssl_context *ssl )
             break;
 #endif /* POLARSSL_ECP_C */
 
+        case TLS_EXT_MAX_FRAGMENT_LENGTH:
+            SSL_DEBUG_MSG( 3, ( "found max fragment length extension" ) );
+
+            ret = ssl_parse_max_fragment_length_ext( ssl, ext + 4, ext_size );
+            if( ret != 0 )
+                return( ret );
+            break;
+
         default:
             SSL_DEBUG_MSG( 3, ( "unknown extension found: %d (ignoring)",
                            ext_id ) );

From a05284964066af1d60d77e3c82733204930f878d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Manuel=20P=C3=A9gouri=C3=A9-Gonnard?= <mpg@elzevir.fr>
Date: Tue, 16 Jul 2013 17:26:28 +0200
Subject: [PATCH 05/16] Send max_fragment_length extension (client)

---
 library/ssl_cli.c | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/library/ssl_cli.c b/library/ssl_cli.c
index aeba799cb..9dbf4e603 100644
--- a/library/ssl_cli.c
+++ b/library/ssl_cli.c
@@ -269,6 +269,30 @@ static void ssl_write_supported_point_formats_ext( ssl_context *ssl,
 }
 #endif
 
+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, ( "client hello, adding 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_client_hello( ssl_context *ssl )
 {
     int ret;
@@ -436,6 +460,9 @@ static int ssl_write_client_hello( ssl_context *ssl )
     ext_len += olen;
 #endif
 
+    ssl_write_max_fragment_length_ext( ssl, p + 2 + ext_len, &olen );
+    ext_len += olen;
+
     SSL_DEBUG_MSG( 3, ( "client hello, total extension length: %d",
                    ext_len ) );
 
@@ -690,6 +717,8 @@ static int ssl_parse_server_hello( ssl_context *ssl )
 
     ext = buf + 44 + n;
 
+    SSL_DEBUG_MSG( 2, ( "server hello, total extension length: %d", ext_len ) );
+
     while( ext_len )
     {
         unsigned int ext_id   = ( ( ext[0] <<  8 )

From de600e571a311d1cd5e47dc78c8c3b46465f2b1f 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 10:14:38 +0200
Subject: [PATCH 06/16] Read max_fragment_length extension (client)

---
 library/ssl_cli.c | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/library/ssl_cli.c b/library/ssl_cli.c
index 9dbf4e603..9050edb84 100644
--- a/library/ssl_cli.c
+++ b/library/ssl_cli.c
@@ -526,6 +526,23 @@ static int ssl_parse_renegotiation_info( ssl_context *ssl,
 
     return( 0 );
 }
+static int ssl_parse_max_fragment_length_ext( ssl_context *ssl,
+                                              unsigned char *buf,
+                                              size_t len )
+{
+    /*
+     * server should use the extension only if we did,
+     * and if so the server's value should match ours (and len is always 1)
+     */
+    if( ssl->mfl_code == SSL_MAX_FRAG_LEN_NONE ||
+        len != 1 ||
+        buf[0] != ssl->mfl_code )
+    {
+        return( POLARSSL_ERR_SSL_BAD_HS_SERVER_HELLO );
+    }
+
+    return( 0 );
+}
 
 static int ssl_parse_server_hello( ssl_context *ssl )
 {
@@ -743,6 +760,17 @@ static int ssl_parse_server_hello( ssl_context *ssl )
 
             break;
 
+        case TLS_EXT_MAX_FRAGMENT_LENGTH:
+            SSL_DEBUG_MSG( 3, ( "found max_fragment_length extension" ) );
+
+            if( ( ret = ssl_parse_max_fragment_length_ext( ssl,
+                            ext + 4, ext_size ) ) != 0 )
+            {
+                return( ret );
+            }
+
+            break;
+
         default:
             SSL_DEBUG_MSG( 3, ( "unknown extension found: %d (ignoring)",
                            ext_id ) );

From f11a6d78c7c07d682f49d923009a99a5db5f6350 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 11:17:14 +0200
Subject: [PATCH 07/16] Rework server extensions writing

---
 library/ssl_srv.c | 76 ++++++++++++++++++++++++++++-------------------
 1 file changed, 45 insertions(+), 31 deletions(-)

diff --git a/library/ssl_srv.c b/library/ssl_srv.c
index 0e3225101..7e1df64b1 100644
--- a/library/ssl_srv.c
+++ b/library/ssl_srv.c
@@ -958,13 +958,42 @@ have_ciphersuite:
     return( 0 );
 }
 
+static void ssl_write_renegotiation_ext( ssl_context *ssl,
+                                         unsigned char *buf,
+                                         size_t *olen )
+{
+    unsigned char *p = buf;
+
+    if( ssl->secure_renegotiation != SSL_SECURE_RENEGOTIATION )
+    {
+        *olen = 0;
+        return;
+    }
+
+    SSL_DEBUG_MSG( 3, ( "server hello, secure renegotiation extension" ) );
+
+    *p++ = (unsigned char)( ( TLS_EXT_RENEGOTIATION_INFO >> 8 ) & 0xFF );
+    *p++ = (unsigned char)( ( TLS_EXT_RENEGOTIATION_INFO      ) & 0xFF );
+
+    *p++ = 0x00;
+    *p++ = ( ssl->verify_data_len * 2 + 1 ) & 0xFF;
+    *p++ = ssl->verify_data_len * 2 & 0xFF;
+
+    memcpy( p, ssl->peer_verify_data, ssl->verify_data_len );
+    p += ssl->verify_data_len;
+    memcpy( p, ssl->own_verify_data, ssl->verify_data_len );
+    p += ssl->verify_data_len;
+
+    *olen = 5 + ssl->verify_data_len * 2;
+}
+
 static int ssl_write_server_hello( ssl_context *ssl )
 {
 #if defined(POLARSSL_HAVE_TIME)
     time_t t;
 #endif
     int ret, n;
-    size_t ext_len = 0;
+    size_t olen, ext_len = 0;
     unsigned char *buf, *p;
 
     SSL_DEBUG_MSG( 2, ( "=> write server hello" ) );
@@ -1010,10 +1039,12 @@ static int ssl_write_server_hello( ssl_context *ssl )
     SSL_DEBUG_BUF( 3, "server hello, random bytes", buf + 6, 32 );
 
     /*
-     *    38  .  38   session id length
-     *    39  . 38+n  session id
-     *   39+n . 40+n  chosen ciphersuite
-     *   41+n . 41+n  chosen compression alg.
+     *    38  .  38     session id length
+     *    39  . 38+n    session id
+     *   39+n . 40+n    chosen ciphersuite
+     *   41+n . 41+n    chosen compression alg.
+     *   42+n . 43+n    extensions length
+     *   44+n . 43+n+m  extensions
      */
     ssl->session_negotiate->length = n = 32;
     *p++ = (unsigned char) ssl->session_negotiate->length;
@@ -1064,34 +1095,17 @@ static int ssl_write_server_hello( ssl_context *ssl )
     SSL_DEBUG_MSG( 3, ( "server hello, compress alg.: %d",
                    ssl->session_negotiate->compression ) );
 
-    if( ssl->secure_renegotiation == SSL_SECURE_RENEGOTIATION )
-    {
-        SSL_DEBUG_MSG( 3, ( "server hello, prepping for secure renegotiation extension" ) );
-        ext_len += 5 + ssl->verify_data_len * 2;
+    /*
+     *  First write extensions, then the total length
+     */
+    ssl_write_renegotiation_ext( ssl, p + 2 + ext_len, &olen );
+    ext_len += olen;
 
-        SSL_DEBUG_MSG( 3, ( "server hello, total extension length: %d",
-                       ext_len ) );
+    SSL_DEBUG_MSG( 3, ( "server hello, total extension length: %d", ext_len ) );
 
-        *p++ = (unsigned char)( ( ext_len >> 8 ) & 0xFF );
-        *p++ = (unsigned char)( ( ext_len      ) & 0xFF );
-
-        /*
-         * Secure renegotiation
-         */
-        SSL_DEBUG_MSG( 3, ( "client hello, secure renegotiation extension" ) );
-
-        *p++ = (unsigned char)( ( TLS_EXT_RENEGOTIATION_INFO >> 8 ) & 0xFF );
-        *p++ = (unsigned char)( ( TLS_EXT_RENEGOTIATION_INFO      ) & 0xFF );
-
-        *p++ = 0x00;
-        *p++ = ( ssl->verify_data_len * 2 + 1 ) & 0xFF;
-        *p++ = ssl->verify_data_len * 2 & 0xFF;
-
-        memcpy( p, ssl->peer_verify_data, ssl->verify_data_len );
-        p += ssl->verify_data_len;
-        memcpy( p, ssl->own_verify_data, ssl->verify_data_len );
-        p += ssl->verify_data_len;
-    }
+    *p++ = (unsigned char)( ( ext_len >> 8 ) & 0xFF );
+    *p++ = (unsigned char)( ( ext_len      ) & 0xFF );
+    p += ext_len;
 
     ssl->out_msglen  = p - buf;
     ssl->out_msgtype = SSL_MSG_HANDSHAKE;

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 08/16] 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 );

From 30dc7ef3adab20f1d23ccc1ba96039a7b84b49c0 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 14:03:42 +0200
Subject: [PATCH 09/16] Reset max_fragment_length in ssl_session_reset()

---
 library/ssl_tls.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index b2d3dc85a..9a1590c58 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -2870,6 +2870,9 @@ int ssl_session_reset( ssl_context *ssl )
     ssl->out_msglen = 0;
     ssl->out_left = 0;
 
+    ssl->mfl_code = SSL_MAX_FRAG_LEN_NONE;
+    ssl->max_frag_len = SSL_MAX_CONTENT_LEN;
+
     ssl->transform_in = NULL;
     ssl->transform_out = NULL;
 

From 6b4f237f6accd027f854f7efa3bdad6b2ba38361 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 14:33:38 +0200
Subject: [PATCH 10/16] Forbid setting max_frag_len > MAX_CONTENT_LEN

---
 library/ssl_tls.c | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index 9a1590c58..d6be98733 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -3119,29 +3119,35 @@ void ssl_set_min_version( ssl_context *ssl, int major, int minor )
 
 int ssl_set_max_frag_len( ssl_context *ssl, unsigned char mfl_code )
 {
+    uint16_t max_frag_len;
+
     switch( mfl_code )
     {
         case SSL_MAX_FRAG_LEN_512:
-            ssl->max_frag_len = 512;
+            max_frag_len = 512;
             break;
 
         case SSL_MAX_FRAG_LEN_1024:
-            ssl->max_frag_len = 1024;
+            max_frag_len = 1024;
             break;
 
         case SSL_MAX_FRAG_LEN_2048:
-            ssl->max_frag_len = 2048;
+            max_frag_len = 2048;
             break;
 
         case SSL_MAX_FRAG_LEN_4096:
-            ssl->max_frag_len = 4096;
+            max_frag_len = 4096;
             break;
 
         default:
             return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
     }
 
+    if( max_frag_len > SSL_MAX_CONTENT_LEN )
+        return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
+
     ssl->mfl_code = mfl_code;
+    ssl->max_frag_len = max_frag_len;
 
     return( 0 );
 }

From bd7ce6311539b69888a70604f7472958760c367d 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 15:34:17 +0200
Subject: [PATCH 11/16] Adapt ssl_server2 to test sending long messages

---
 programs/ssl/ssl_server2.c | 37 +++++++++++++++++++++++--------------
 1 file changed, 23 insertions(+), 14 deletions(-)

diff --git a/programs/ssl/ssl_server2.c b/programs/ssl/ssl_server2.c
index 5b7639aed..d367c4ec6 100644
--- a/programs/ssl/ssl_server2.c
+++ b/programs/ssl/ssl_server2.c
@@ -69,10 +69,16 @@
 #define DFL_MAX_VERSION         -1
 #define DFL_AUTH_MODE           SSL_VERIFY_OPTIONAL
 
+#define LONG_RESPONSE "<p>blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah\r\n" \
+    "blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah\r\n"  \
+    "blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah\r\n"  \
+    "blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah</p>\r\n"
+
+/* Uncomment LONG_RESPONSE to test sending long paquets */
 #define HTTP_RESPONSE \
     "HTTP/1.0 200 OK\r\nContent-Type: text/html\r\n\r\n" \
     "<h2>PolarSSL Test Server</h2>\r\n" \
-    "<p>Successful connection using: %s</p>\r\n"
+    "<p>Successful connection using: %s</p>\r\n" // LONG_RESPONSE
 
 /*
  * global options
@@ -168,7 +174,7 @@ int main( int argc, char *argv[] )
 #else
 int main( int argc, char *argv[] )
 {
-    int ret = 0, len;
+    int ret = 0, len, written;
     int listen_fd;
     int client_fd = -1;
     unsigned char buf[1024];
@@ -748,7 +754,7 @@ reset:
         }
 
         len = ret;
-        printf( " %d bytes read\n\n%s", len, (char *) buf );
+        printf( " %d bytes read\n\n%s\n", len, (char *) buf );
 
         if( memcmp( buf, "SERVERQUIT", 10 ) == 0 )
             goto exit;
@@ -767,23 +773,26 @@ reset:
     len = sprintf( (char *) buf, HTTP_RESPONSE,
                    ssl_get_ciphersuite( &ssl ) );
 
-    while( ( ret = ssl_write( &ssl, buf, len ) ) <= 0 )
+    for( written = 0; written < len; written += ret )
     {
-        if( ret == POLARSSL_ERR_NET_CONN_RESET )
+        while( ( ret = ssl_write( &ssl, buf + written, len - written ) ) <= 0 )
         {
-            printf( " failed\n  ! peer closed the connection\n\n" );
-            goto reset;
-        }
+            if( ret == POLARSSL_ERR_NET_CONN_RESET )
+            {
+                printf( " failed\n  ! peer closed the connection\n\n" );
+                goto reset;
+            }
 
-        if( ret != POLARSSL_ERR_NET_WANT_READ && ret != POLARSSL_ERR_NET_WANT_WRITE )
-        {
-            printf( " failed\n  ! ssl_write returned %d\n\n", ret );
-            goto exit;
+            if( ret != POLARSSL_ERR_NET_WANT_READ && ret != POLARSSL_ERR_NET_WANT_WRITE )
+            {
+                printf( " failed\n  ! ssl_write returned %d\n\n", ret );
+                goto exit;
+            }
         }
     }
 
-    len = ret;
-    printf( " %d bytes written\n\n%s\n", len, (char *) buf );
+    buf[written] = '\0';
+    printf( " %d bytes written\n\n%s\n", written, (char *) buf );
 
     ret = 0;
     goto reset;

From 8e714d7acad8b68e4be7aa6fde88c75b75b44c36 Mon Sep 17 00:00:00 2001
From: Paul Bakker <p.j.bakker@polarssl.org>
Date: Thu, 18 Jul 2013 11:05:13 +0200
Subject: [PATCH 12/16] Modified LONG_RESPONSE and comments in ssl_server2

---
 programs/ssl/ssl_server2.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/programs/ssl/ssl_server2.c b/programs/ssl/ssl_server2.c
index d367c4ec6..ab2a87f7a 100644
--- a/programs/ssl/ssl_server2.c
+++ b/programs/ssl/ssl_server2.c
@@ -69,12 +69,13 @@
 #define DFL_MAX_VERSION         -1
 #define DFL_AUTH_MODE           SSL_VERIFY_OPTIONAL
 
-#define LONG_RESPONSE "<p>blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah\r\n" \
-    "blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah\r\n"  \
-    "blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah\r\n"  \
-    "blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah</p>\r\n"
+#define LONG_RESPONSE "<p>01-blah-blah-blah-blah-blah-blah-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-blah-blah-blah-blah-blah-blah\r\n"  \
+    "03-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah\r\n"  \
+    "04-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah</p>\r\n"
 
-/* Uncomment LONG_RESPONSE to test sending long paquets */
+/* Uncomment LONG_RESPONSE at the end of HTTP_RESPONSE to test sending longer
+ * packets (for fragmentation purposes) */
 #define HTTP_RESPONSE \
     "HTTP/1.0 200 OK\r\nContent-Type: text/html\r\n\r\n" \
     "<h2>PolarSSL Test Server</h2>\r\n" \

From 581e6b6d6cbdc2f913876fd4c0cfb1531da87e66 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Manuel=20P=C3=A9gouri=C3=A9-Gonnard?= <mpg@elzevir.fr>
Date: Thu, 18 Jul 2013 12:32:27 +0200
Subject: [PATCH 13/16] Prepare migrating max fragment length to session

Remove max_frag_len member so that reseting session by memset()ing it to zero
does the right thing.
---
 include/polarssl/ssl.h |  4 +--
 library/ssl_tls.c      | 56 ++++++++++++++++++++----------------------
 2 files changed, 29 insertions(+), 31 deletions(-)

diff --git a/include/polarssl/ssl.h b/include/polarssl/ssl.h
index 24e60f793..5b4e36f2f 100644
--- a/include/polarssl/ssl.h
+++ b/include/polarssl/ssl.h
@@ -117,7 +117,8 @@
 #define SSL_MINOR_VERSION_2             2   /*!< TLS v1.1 */
 #define SSL_MINOR_VERSION_3             3   /*!< TLS v1.2 */
 
-/* RFC 6066 section 4 */
+/* RFC 6066 section 4, see also mfl_code_to_length in ssl_tls.c
+ * NONE must be zero so that memset()ing session to zero works */
 #define SSL_MAX_FRAG_LEN_NONE           0   /*!< don't use this extension   */
 #define SSL_MAX_FRAG_LEN_512            1   /*!< MaxFragmentLength 2^9      */
 #define SSL_MAX_FRAG_LEN_1024           2   /*!< MaxFragmentLength 2^10     */
@@ -509,7 +510,6 @@ struct _ssl_context
 
     /* Maximum fragment length extension (RFC 6066 section 4) */
     unsigned char mfl_code;     /*!< numerical code for MaxFragmentLength   */
-    uint16_t max_frag_len;      /*!< value of MaxFragmentLength             */
 
     /*
      * PKI layer
diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index d6be98733..0374ee818 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -59,6 +59,23 @@
 #define strcasecmp _stricmp
 #endif
 
+/*
+ * Convert max_fragment_length codes to length.
+ * RFC 6066 says:
+ *    enum{
+ *        2^9(1), 2^10(2), 2^11(3), 2^12(4), (255)
+ *    } MaxFragmentLength;
+ * and we add 0 -> extension unused
+ */
+static unsigned int mfl_code_to_length[] =
+{
+    SSL_MAX_CONTENT_LEN,    /* SSL_MAX_FRAG_LEN_NONE */
+    512,                    /* SSL_MAX_FRAG_LEN_512  */
+    1024,                   /* SSL_MAX_FRAG_LEN_1024 */
+    2048,                   /* SSL_MAX_FRAG_LEN_2048 */
+    4096,                   /* SSL_MAX_FRAG_LEN_4096 */
+};
+
 #if defined(POLARSSL_SSL_HW_RECORD_ACCEL)
 int (*ssl_hw_record_init)(ssl_context *ssl,
                        const unsigned char *key_enc, const unsigned char *key_dec,
@@ -2827,7 +2844,6 @@ int ssl_init( ssl_context *ssl )
     memset( ssl->out_ctr, 0, SSL_BUFFER_LEN );
 
     ssl->mfl_code = SSL_MAX_FRAG_LEN_NONE;
-    ssl->max_frag_len = SSL_MAX_CONTENT_LEN;
 
     ssl->hostname = NULL;
     ssl->hostname_len = 0;
@@ -2871,7 +2887,6 @@ int ssl_session_reset( ssl_context *ssl )
     ssl->out_left = 0;
 
     ssl->mfl_code = SSL_MAX_FRAG_LEN_NONE;
-    ssl->max_frag_len = SSL_MAX_CONTENT_LEN;
 
     ssl->transform_in = NULL;
     ssl->transform_out = NULL;
@@ -3119,35 +3134,13 @@ void ssl_set_min_version( ssl_context *ssl, int major, int minor )
 
 int ssl_set_max_frag_len( ssl_context *ssl, unsigned char mfl_code )
 {
-    uint16_t max_frag_len;
-
-    switch( mfl_code )
+    if( mfl_code >= sizeof( mfl_code_to_length ) ||
+        mfl_code_to_length[mfl_code] > SSL_MAX_CONTENT_LEN )
     {
-        case SSL_MAX_FRAG_LEN_512:
-            max_frag_len = 512;
-            break;
-
-        case SSL_MAX_FRAG_LEN_1024:
-            max_frag_len = 1024;
-            break;
-
-        case SSL_MAX_FRAG_LEN_2048:
-            max_frag_len = 2048;
-            break;
-
-        case SSL_MAX_FRAG_LEN_4096:
-            max_frag_len = 4096;
-            break;
-
-        default:
-            return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
+        return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
     }
 
-    if( max_frag_len > SSL_MAX_CONTENT_LEN )
-        return( POLARSSL_ERR_SSL_BAD_INPUT_DATA );
-
     ssl->mfl_code = mfl_code;
-    ssl->max_frag_len = max_frag_len;
 
     return( 0 );
 }
@@ -3413,6 +3406,7 @@ int ssl_write( ssl_context *ssl, const unsigned char *buf, size_t len )
 {
     int ret;
     size_t n;
+    unsigned int max_len;
 
     SSL_DEBUG_MSG( 2, ( "=> write" ) );
 
@@ -3425,8 +3419,12 @@ int ssl_write( ssl_context *ssl, const unsigned char *buf, size_t len )
         }
     }
 
-    n = ( len < ssl->max_frag_len )
-        ? len : ssl->max_frag_len;
+    /*
+     * Assume mfl_code is correct since it was checked when set
+     */
+    max_len = mfl_code_to_length[ssl->mfl_code];
+
+    n = ( len < max_len) ? len : max_len;
 
     if( ssl->out_left != 0 )
     {

From ed4af8b57cefdf9cf6ce1bfee79f4d1f6139112d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Manuel=20P=C3=A9gouri=C3=A9-Gonnard?= <mpg@elzevir.fr>
Date: Thu, 18 Jul 2013 14:07:09 +0200
Subject: [PATCH 14/16] Move negotiated max fragment length to session

User-set max fragment length remains in ssl_context.
The min of the two is used for sizing fragments.
---
 include/polarssl/ssl.h |  6 ++++--
 library/ssl_srv.c      | 11 +++++------
 library/ssl_tls.c      | 13 ++++++++++---
 3 files changed, 19 insertions(+), 11 deletions(-)

diff --git a/include/polarssl/ssl.h b/include/polarssl/ssl.h
index 5b4e36f2f..e9e33e357 100644
--- a/include/polarssl/ssl.h
+++ b/include/polarssl/ssl.h
@@ -124,6 +124,7 @@
 #define SSL_MAX_FRAG_LEN_1024           2   /*!< MaxFragmentLength 2^10     */
 #define SSL_MAX_FRAG_LEN_2048           3   /*!< MaxFragmentLength 2^11     */
 #define SSL_MAX_FRAG_LEN_4096           4   /*!< MaxFragmentLength 2^12     */
+#define SSL_MAX_FRAG_LEN_INVALID        5   /*!< first invalid value        */
 
 #define SSL_IS_CLIENT                   0
 #define SSL_IS_SERVER                   1
@@ -330,6 +331,8 @@ struct _ssl_session
 #if defined(POLARSSL_X509_PARSE_C)
     x509_cert *peer_cert;       /*!< peer X.509 cert chain */
 #endif /* POLARSSL_X509_PARSE_C */
+
+    unsigned char mfl_code;     /*!< MaxFragmentLength negotiated by peer */
 };
 
 /*
@@ -508,8 +511,7 @@ struct _ssl_context
     size_t out_msglen;          /*!< record header: message length    */
     size_t out_left;            /*!< amount of data not yet written   */
 
-    /* Maximum fragment length extension (RFC 6066 section 4) */
-    unsigned char mfl_code;     /*!< numerical code for MaxFragmentLength   */
+    unsigned char mfl_code;     /*!< MaxFragmentLength chosen by us   */
 
     /*
      * PKI layer
diff --git a/library/ssl_srv.c b/library/ssl_srv.c
index 2177253f3..abcc867dd 100644
--- a/library/ssl_srv.c
+++ b/library/ssl_srv.c
@@ -295,15 +295,14 @@ static int ssl_parse_max_fragment_length_ext( ssl_context *ssl,
                                               const unsigned char *buf,
                                               size_t len )
 {
-    int ret;
-
-    if( len != 1 ||
-        ( ret = ssl_set_max_frag_len( ssl, buf[0] ) ) != 0 )
+    if( len != 1 || buf[0] >= SSL_MAX_FRAG_LEN_INVALID )
     {
         SSL_DEBUG_MSG( 1, ( "bad client hello message" ) );
         return( POLARSSL_ERR_SSL_BAD_HS_CLIENT_HELLO );
     }
 
+    ssl->session_negotiate->mfl_code = buf[0];
+
     return( 0 );
 }
 
@@ -993,7 +992,7 @@ static void ssl_write_max_fragment_length_ext( ssl_context *ssl,
 {
     unsigned char *p = buf;
 
-    if( ssl->mfl_code == SSL_MAX_FRAG_LEN_NONE ) {
+    if( ssl->session_negotiate->mfl_code == SSL_MAX_FRAG_LEN_NONE ) {
         *olen = 0;
         return;
     }
@@ -1006,7 +1005,7 @@ static void ssl_write_max_fragment_length_ext( ssl_context *ssl,
     *p++ = 0x00;
     *p++ = 1;
 
-    *p++ = ssl->mfl_code;
+    *p++ = ssl->session_negotiate->mfl_code;
 
     *olen = 5;
 }
diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index 0374ee818..a230dc939 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -67,7 +67,7 @@
  *    } MaxFragmentLength;
  * and we add 0 -> extension unused
  */
-static unsigned int mfl_code_to_length[] =
+static unsigned int mfl_code_to_length[SSL_MAX_FRAG_LEN_INVALID] =
 {
     SSL_MAX_CONTENT_LEN,    /* SSL_MAX_FRAG_LEN_NONE */
     512,                    /* SSL_MAX_FRAG_LEN_512  */
@@ -2886,8 +2886,6 @@ int ssl_session_reset( ssl_context *ssl )
     ssl->out_msglen = 0;
     ssl->out_left = 0;
 
-    ssl->mfl_code = SSL_MAX_FRAG_LEN_NONE;
-
     ssl->transform_in = NULL;
     ssl->transform_out = NULL;
 
@@ -3424,6 +3422,15 @@ int ssl_write( ssl_context *ssl, const unsigned char *buf, size_t len )
      */
     max_len = mfl_code_to_length[ssl->mfl_code];
 
+    /*
+     * Check if a smaller max length was negociated
+     */
+    if( ssl->session_out != NULL &&
+        mfl_code_to_length[ssl->session_out->mfl_code] < max_len )
+    {
+        max_len = mfl_code_to_length[ssl->session_out->mfl_code];
+    }
+
     n = ( len < max_len) ? len : max_len;
 
     if( ssl->out_left != 0 )

From 0c017a55e0fb50e9ed4c77ff512ce8bc0bcebb29 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Manuel=20P=C3=A9gouri=C3=A9-Gonnard?= <mpg@elzevir.fr>
Date: Thu, 18 Jul 2013 14:07:36 +0200
Subject: [PATCH 15/16] Add max_frag_len option in ssl_server2

Also reformat code and output more information in ssl_client2
---
 programs/ssl/ssl_client2.c | 17 ++++++++++++-----
 programs/ssl/ssl_server2.c | 37 ++++++++++++++++++++++++++++++-------
 2 files changed, 42 insertions(+), 12 deletions(-)

diff --git a/programs/ssl/ssl_client2.c b/programs/ssl/ssl_client2.c
index 0a7048120..0c770f6d9 100644
--- a/programs/ssl/ssl_client2.c
+++ b/programs/ssl/ssl_client2.c
@@ -59,8 +59,15 @@
 #define DFL_AUTH_MODE           SSL_VERIFY_OPTIONAL
 #define DFL_MFL_CODE            SSL_MAX_FRAG_LEN_NONE
 
-/* Uncomment to test sending long paquets */
-#define LONG_HEADER // "User-agent: blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-END\r\n"
+/* Uncomment to test sending longer paquets (for fragmentation purposes) */
+#define LONG_HEADER // "User-agent: blah-blah-blah-blah-blah-blah-blah-"     \
+    "-01--blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-" \
+    "-02--blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-" \
+    "-03--blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-" \
+    "-04--blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-" \
+    "-05--blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-" \
+    "-06--blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-" \
+    "-07--blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-END\r\n"
 
 #define GET_REQUEST "GET %s HTTP/1.0\r\n" LONG_HEADER "\r\n"
 
@@ -204,7 +211,7 @@ int main( int argc, char *argv[] )
 #else
 int main( int argc, char *argv[] )
 {
-    int ret = 0, len, server_fd, i, written;
+    int ret = 0, len, server_fd, i, written, frags;
     unsigned char buf[1024];
 #if defined(POLARSSL_KEY_EXCHANGE_PSK_ENABLED)
     unsigned char psk[256];
@@ -705,7 +712,7 @@ int main( int argc, char *argv[] )
 
     len = sprintf( (char *) buf, GET_REQUEST, opt.request_page );
 
-    for( written = 0; written < len; written += ret )
+    for( written = 0, frags = 0; written < len; written += ret, frags++ )
     {
         while( ( ret = ssl_write( &ssl, buf + written, len - written ) ) <= 0 )
         {
@@ -718,7 +725,7 @@ int main( int argc, char *argv[] )
     }
 
     buf[written] = '\0';
-    printf( " %d bytes written\n\n%s\n", written, (char *) buf );
+    printf( " %d bytes written in %d fragments\n\n%s\n", written, frags, (char *) buf );
 
     /*
      * 7. Read the HTTP response
diff --git a/programs/ssl/ssl_server2.c b/programs/ssl/ssl_server2.c
index ab2a87f7a..d5ebb812b 100644
--- a/programs/ssl/ssl_server2.c
+++ b/programs/ssl/ssl_server2.c
@@ -68,11 +68,15 @@
 #define DFL_MIN_VERSION         -1
 #define DFL_MAX_VERSION         -1
 #define DFL_AUTH_MODE           SSL_VERIFY_OPTIONAL
+#define DFL_MFL_CODE            SSL_MAX_FRAG_LEN_NONE
 
-#define LONG_RESPONSE "<p>01-blah-blah-blah-blah-blah-blah-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-blah-blah-blah-blah-blah-blah\r\n"  \
-    "03-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah\r\n"  \
-    "04-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah</p>\r\n"
+#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"  \
+    "03-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah\r\n"  \
+    "04-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah\r\n"  \
+    "05-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah\r\n"  \
+    "06-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah\r\n"  \
+    "07-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah</p>\r\n"
 
 /* Uncomment LONG_RESPONSE at the end of HTTP_RESPONSE to test sending longer
  * packets (for fragmentation purposes) */
@@ -100,6 +104,7 @@ struct options
     int min_version;            /* minimum protocol version accepted        */
     int max_version;            /* maximum protocol version accepted        */
     int auth_mode;              /* verify mode for connection               */
+    unsigned char mfl_code;     /* code for maximum fragment length         */
 } opt;
 
 static void my_debug( void *ctx, int level, const char *str )
@@ -154,6 +159,8 @@ static void my_debug( void *ctx, int level, const char *str )
     "                        options: ssl3, tls1, tls1_1, tls1_2\n" \
     "    auth_mode=%%s        default: \"optional\"\n"      \
     "                        options: none, optional, required\n" \
+    "    max_frag_len=%%d     default: 16384 (tls default)" \
+    "                        options: 512, 1024, 2048, 4096" \
     USAGE_PSK                                               \
     "\n"                                                    \
     "    force_ciphersuite=<name>    default: all enabled\n"\
@@ -175,7 +182,7 @@ int main( int argc, char *argv[] )
 #else
 int main( int argc, char *argv[] )
 {
-    int ret = 0, len, written;
+    int ret = 0, len, written, frags;
     int listen_fd;
     int client_fd = -1;
     unsigned char buf[1024];
@@ -257,6 +264,7 @@ int main( int argc, char *argv[] )
     opt.min_version         = DFL_MIN_VERSION;
     opt.max_version         = DFL_MAX_VERSION;
     opt.auth_mode           = DFL_AUTH_MODE;
+    opt.mfl_code            = DFL_MFL_CODE;
 
     for( i = 1; i < argc; i++ )
     {
@@ -375,6 +383,19 @@ int main( int argc, char *argv[] )
             else
                 goto usage;
         }
+        else if( strcmp( p, "max_frag_len" ) == 0 )
+        {
+            if( strcmp( q, "512" ) == 0 )
+                opt.mfl_code = SSL_MAX_FRAG_LEN_512;
+            else if( strcmp( q, "1024" ) == 0 )
+                opt.mfl_code = SSL_MAX_FRAG_LEN_1024;
+            else if( strcmp( q, "2048" ) == 0 )
+                opt.mfl_code = SSL_MAX_FRAG_LEN_2048;
+            else if( strcmp( q, "4096" ) == 0 )
+                opt.mfl_code = SSL_MAX_FRAG_LEN_4096;
+            else
+                goto usage;
+        }
         else
             goto usage;
     }
@@ -569,6 +590,8 @@ int main( int argc, char *argv[] )
     ssl_set_endpoint( &ssl, SSL_IS_SERVER );
     ssl_set_authmode( &ssl, opt.auth_mode );
 
+    ssl_set_max_frag_len( &ssl, opt.mfl_code );
+
     ssl_set_rng( &ssl, ctr_drbg_random, &ctr_drbg );
     ssl_set_dbg( &ssl, my_debug, stdout );
 
@@ -774,7 +797,7 @@ reset:
     len = sprintf( (char *) buf, HTTP_RESPONSE,
                    ssl_get_ciphersuite( &ssl ) );
 
-    for( written = 0; written < len; written += ret )
+    for( written = 0, frags = 0; written < len; written += ret, frags++ )
     {
         while( ( ret = ssl_write( &ssl, buf + written, len - written ) ) <= 0 )
         {
@@ -793,7 +816,7 @@ reset:
     }
 
     buf[written] = '\0';
-    printf( " %d bytes written\n\n%s\n", written, (char *) buf );
+    printf( " %d bytes written in %d fragments\n\n%s\n", written, frags, (char *) buf );
 
     ret = 0;
     goto reset;

From e048b67d0a2f73166b405194d489ff9fa7ee2f2b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Manuel=20P=C3=A9gouri=C3=A9-Gonnard?= <mpg@elzevir.fr>
Date: Fri, 19 Jul 2013 12:47:00 +0200
Subject: [PATCH 16/16] Misc minor fixes

- avoid "multi-line comment" warning in ssl_client2.c
- rm useless initialisation of mfl_code in ssl_init()
- const-correctness of ssl_parse_*_ext()
- a code formating issue
---
 include/polarssl/ssl.h     | 2 +-
 library/ssl_cli.c          | 4 ++--
 library/ssl_srv.c          | 3 ++-
 library/ssl_tls.c          | 2 --
 programs/ssl/ssl_client2.c | 7 ++++---
 5 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/include/polarssl/ssl.h b/include/polarssl/ssl.h
index e9e33e357..4e1d25a83 100644
--- a/include/polarssl/ssl.h
+++ b/include/polarssl/ssl.h
@@ -118,7 +118,7 @@
 #define SSL_MINOR_VERSION_3             3   /*!< TLS v1.2 */
 
 /* RFC 6066 section 4, see also mfl_code_to_length in ssl_tls.c
- * NONE must be zero so that memset()ing session to zero works */
+ * NONE must be zero so that memset()ing structure to zero works */
 #define SSL_MAX_FRAG_LEN_NONE           0   /*!< don't use this extension   */
 #define SSL_MAX_FRAG_LEN_512            1   /*!< MaxFragmentLength 2^9      */
 #define SSL_MAX_FRAG_LEN_1024           2   /*!< MaxFragmentLength 2^10     */
diff --git a/library/ssl_cli.c b/library/ssl_cli.c
index 9050edb84..c89bf0cb0 100644
--- a/library/ssl_cli.c
+++ b/library/ssl_cli.c
@@ -488,7 +488,7 @@ static int ssl_write_client_hello( ssl_context *ssl )
 }
 
 static int ssl_parse_renegotiation_info( ssl_context *ssl,
-                                         unsigned char *buf,
+                                         const unsigned char *buf,
                                          size_t len )
 {
     int ret;
@@ -527,7 +527,7 @@ static int ssl_parse_renegotiation_info( ssl_context *ssl,
     return( 0 );
 }
 static int ssl_parse_max_fragment_length_ext( ssl_context *ssl,
-                                              unsigned char *buf,
+                                              const unsigned char *buf,
                                               size_t len )
 {
     /*
diff --git a/library/ssl_srv.c b/library/ssl_srv.c
index abcc867dd..3e1838667 100644
--- a/library/ssl_srv.c
+++ b/library/ssl_srv.c
@@ -992,7 +992,8 @@ static void ssl_write_max_fragment_length_ext( ssl_context *ssl,
 {
     unsigned char *p = buf;
 
-    if( ssl->session_negotiate->mfl_code == SSL_MAX_FRAG_LEN_NONE ) {
+    if( ssl->session_negotiate->mfl_code == SSL_MAX_FRAG_LEN_NONE )
+    {
         *olen = 0;
         return;
     }
diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index a230dc939..f701a8a1f 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -2843,8 +2843,6 @@ int ssl_init( ssl_context *ssl )
     memset( ssl-> in_ctr, 0, SSL_BUFFER_LEN );
     memset( ssl->out_ctr, 0, SSL_BUFFER_LEN );
 
-    ssl->mfl_code = SSL_MAX_FRAG_LEN_NONE;
-
     ssl->hostname = NULL;
     ssl->hostname_len = 0;
 
diff --git a/programs/ssl/ssl_client2.c b/programs/ssl/ssl_client2.c
index 0c770f6d9..56d0e9112 100644
--- a/programs/ssl/ssl_client2.c
+++ b/programs/ssl/ssl_client2.c
@@ -59,8 +59,7 @@
 #define DFL_AUTH_MODE           SSL_VERIFY_OPTIONAL
 #define DFL_MFL_CODE            SSL_MAX_FRAG_LEN_NONE
 
-/* Uncomment to test sending longer paquets (for fragmentation purposes) */
-#define LONG_HEADER // "User-agent: blah-blah-blah-blah-blah-blah-blah-"     \
+#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-" \
     "-02--blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-" \
     "-03--blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-" \
@@ -69,7 +68,9 @@
     "-06--blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-" \
     "-07--blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-blah-END\r\n"
 
-#define GET_REQUEST "GET %s HTTP/1.0\r\n" LONG_HEADER "\r\n"
+/* Uncomment LONG_HEADER in the definition of GET_REQUEST to test sending
+ * longer paquets (for fragmentation purposes) */
+#define GET_REQUEST "GET %s HTTP/1.0\r\n" /* LONG_HEADER */ "\r\n"
 
 /*
  * global options