Added config options 'mtu' and 'output-buffer'.

NEWS

@@ -5,6 +5,9 @@
   the suggested values and ignores the other.
 - Reduce limit of output buffer on DTLS socket to reduce latency (following
   similar openconnect change).
+- Added config option "output-buffer" to allow selecting between high throughput 
+  or low latency.
+- Enabled config option "mtu".
 
 
 * Version 0.1.6 (released 2013-09-02)

doc/sample.config

@@ -161,6 +161,11 @@ ping-leases = false
 # Leave empty to assign the default MTU of the device
 # mtu = 
 
+# The number of packets (of MTU size) that are available in
+# the output buffer. The default is low to improve latency.
+# Setting it higher will improve throughput.
+output-buffer = 10
+
 route = 192.168.1.0/255.255.255.0
 #route = 192.168.5.0/255.255.255.0
 

src/config.c

@@ -202,6 +202,9 @@ unsigned j;
 	READ_STRING("tls-priorities", config->priorities, 0);
 	READ_STRING("chroot-dir", config->chroot_dir, 0);
 
+	READ_NUMERIC("mtu", config->default_mtu, 0);
+	READ_NUMERIC("output-buffer", config->output_buffer, 0);
+
 	READ_NUMERIC("cookie-validity", config->cookie_validity, 1);
 	READ_NUMERIC("auth-timeout", config->auth_timeout, 0);
 	READ_NUMERIC("max-clients", config->max_clients, 0);

src/ocserv-args.c

@@ -2,7 +2,7 @@
  *  
  *  DO NOT EDIT THIS FILE   (ocserv-args.c)
  *  
- *  It has been AutoGen-ed  October  5, 2013 at 09:36:46 AM by AutoGen 5.17
+ *  It has been AutoGen-ed  October 20, 2013 at 05:44:06 PM by AutoGen 5.17
  *  From the definitions    ocserv-args.def
  *  and the template file   options
  *

src/ocserv-args.def

@@ -249,6 +249,11 @@ ping-leases = false
 # Unset to assign the default MTU of the device
 # mtu = 
 
+# The number of packets (of MTU size) that are available in
+# the output buffer. The default is low to improve latency.
+# Setting it higher will improve throughput.
+output-buffer = 10
+
 # Routes to be forwarded to the client. If you need the
 # client to forward routes to the server, you may use the connect 
 # and disconnect scripts.

src/ocserv-args.h

@@ -2,7 +2,7 @@
  *  
  *  DO NOT EDIT THIS FILE   (ocserv-args.h)
  *  
- *  It has been AutoGen-ed  October  5, 2013 at 09:36:46 AM by AutoGen 5.17
+ *  It has been AutoGen-ed  October 20, 2013 at 05:44:06 PM by AutoGen 5.17
  *  From the definitions    ocserv-args.def
  *  and the template file   options
  *

src/vpn.h

@@ -112,6 +112,9 @@ struct cfg_st {
 	unsigned force_cert_auth; /* always require client certificate */
 	unsigned rate_limit_ms; /* if non zero force a connection every rate_limit milliseconds */
 	unsigned ping_leases; /* non zero if we need to ping prior to leasing */
+	
+	unsigned output_buffer;
+	unsigned default_mtu;
 
 	char *connect_script;
 	char *disconnect_script;

src/worker-vpn.c

@@ -912,6 +912,10 @@ socklen_t sl;
 		);
 	SEND_ERR(ret);
 
+	if (ws->config->default_mtu > 0) {
+		vinfo.mtu = ws->config->default_mtu;
+	}
+
 	mtu_overhead = CSTP_OVERHEAD;
 	ws->conn_mtu = vinfo.mtu - mtu_overhead;
 	if (req->cstp_mtu > 0) {
@@ -979,8 +983,10 @@ socklen_t sl;
 		tls_printf(ws->session, "X-DTLS-MTU: %u\r\n", dtls_mtu);
 		oclog(ws, LOG_INFO, "suggesting DTLS MTU %u", dtls_mtu);
 		
-		sndbuf = ws->conn_mtu * 4;
+		if (ws->config->output_buffer > 0) {
-		setsockopt( ws->udp_fd, SOL_SOCKET, SO_SNDBUF, &sndbuf, sizeof(sndbuf));
+			sndbuf = ws->conn_mtu * ws->config->output_buffer;
+			setsockopt( ws->udp_fd, SOL_SOCKET, SO_SNDBUF, &sndbuf, sizeof(sndbuf));
+		}
 	} else
 		dtls_mtu = 0;