commit e7675d0d3df9f89b784ea0b3c9d552e12062776f
author Hanno Becker <hanno.becker@arm.com> Tue Aug 14 13:28:56 2018 +0100
committer Hanno Becker <hanno.becker@arm.com> Fri Aug 17 15:45:33 2018 +0100
tree b2beca0653c9b8a2080e26296023a01dab55dd95
parent 04da1892256999a9549775820758a187fcb19070

Add cmd line option to ssl_server2 for datagram packing

This commit adds a new command line option `dgram_packing`
to the example server application programs/ssl/ssl_server2
allowing to allow/forbid the use of datagram packing.

programs/ssl/ssl_server2.c

diff --git a/programs/ssl/ssl_server2.c b/programs/ssl/ssl_server2.c
index 484f84f..12f8276 100644
--- a/programs/ssl/ssl_server2.c
+++ b/programs/ssl/ssl_server2.c
@@ -152,6 +152,7 @@
 #define DFL_HS_TO_MAX           0
 #define DFL_DTLS_MTU            -1
 #define DFL_BADMAC_LIMIT        -1
+#define DFL_DGRAM_PACKING        1
 #define DFL_EXTENDED_MS         -1
 #define DFL_ETM                 -1
 
@@ -299,7 +300,10 @@
     "    dtls=%%d             default: 0 (TLS)\n"                           \
     "    hs_timeout=%%d-%%d    default: (library default: 1000-60000)\n"    \
     "                        range of DTLS handshake timeouts in millisecs\n" \
-    "    mtu=%%d              default: (library default: unlimited)\n"
+    "    mtu=%%d              default: (library default: unlimited)\n"  \
+    "    dgram_packing=%%d    default: 1 (allowed)\n"                   \
+    "                        allow or forbid packing of multiple\n" \
+    "                        records within a single datgram.\n"
 #else
 #define USAGE_DTLS ""
 #endif
@@ -473,6 +477,7 @@
     uint32_t hs_to_min;         /* Initial value of DTLS handshake timer    */
     uint32_t hs_to_max;         /* Max value of DTLS handshake timer        */
     int dtls_mtu;               /* UDP Maximum tranport unit for DTLS       */
+    int dgram_packing;          /* allow/forbid datagram packing            */
     int badmac_limit;           /* Limit of records with bad MAC            */
 } opt;
 
@@ -1342,6 +1347,7 @@
     opt.hs_to_min           = DFL_HS_TO_MIN;
     opt.hs_to_max           = DFL_HS_TO_MAX;
     opt.dtls_mtu            = DFL_DTLS_MTU;
+    opt.dgram_packing       = DFL_DGRAM_PACKING;
     opt.badmac_limit        = DFL_BADMAC_LIMIT;
     opt.extended_ms         = DFL_EXTENDED_MS;
     opt.etm                 = DFL_ETM;
@@ -1694,6 +1700,15 @@
             if( opt.dtls_mtu < 0 )
                 goto usage;
         }
+        else if( strcmp( p, "dgram_packing" ) == 0 )
+        {
+            opt.dgram_packing = atoi( q );
+            if( opt.dgram_packing != 0 &&
+                opt.dgram_packing != 1 )
+            {
+                goto usage;
+            }
+        }
         else if( strcmp( p, "sni" ) == 0 )
         {
             opt.sni = q;
@@ -2168,6 +2183,9 @@
 
     if( opt.dtls_mtu != DFL_DTLS_MTU )
         mbedtls_ssl_conf_mtu( &conf, opt.dtls_mtu );
+
+    if( opt.dgram_packing != DFL_DGRAM_PACKING )
+        mbedtls_ssl_conf_datagram_packing( &ssl, opt.dgram_packing );
 #endif /* MBEDTLS_SSL_PROTO_DTLS */
 
 #if defined(MBEDTLS_SSL_MAX_FRAGMENT_LENGTH)
@@ -2178,6 +2196,7 @@
     };
 #endif
 
+
 #if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
     if( opt.trunc_hmac != DFL_TRUNC_HMAC )
         mbedtls_ssl_conf_truncated_hmac( &conf, opt.trunc_hmac );