Merge pull request #761 from claws/add_dscp_sockopt

Add ability to set Differential Services Code Point socket option

.gitignore

@@ -82,6 +82,7 @@ tests/test_shutdown_stress_tipc
 tests/test_sub_forward_tipc
 tests/test_term_endpoint_tipc
 tests/test_many_sockets
+tests/test_diffserv
 tests/test*.log
 tests/test*.trs
 src/platform.hpp*

doc/zmq_getsockopt.txt

@@ -352,6 +352,17 @@ Default value:: 1 (true)
 Applicable socket types:: all, when using TCP transports.
 
 
+ZMQ_TOS: Retrieve the Type-of-Service socket override status
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Retrieve the IP_TOS option for the socket.
+
+[horizontal]
+Option value type:: int
+Option value unit:: >0
+Default value:: 0
+Applicable socket types:: all, only for connection-oriented transports
+
+
 ZMQ_IMMEDIATE: Retrieve attach-on-connect value
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 Retrieve the state of the attach on connect value. If set to `1`, will delay the

doc/zmq_setsockopt.txt

@@ -377,6 +377,21 @@ Default value:: 1 (true)
 Applicable socket types:: all, when using TCP transports.
 
 
+ZMQ_TOS: Set the Type-of-Service on socket
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Sets the ToS fields (Differentiated services (DS) and Explicit Congestion Notification
+(ECN) field of the IP header. The ToS field is typically used to specify a packets
+priority. The availability of this option is dependent on intermediate network
+equipment that inspect the ToS field andprovide a path for low-delay, high-throughput,
+highly-reliable service, etc.
+
+[horizontal]
+Option value type:: int
+Option value unit:: >0
+Default value:: 0
+Applicable socket types:: all, only for connection-oriented transports
+
+
 ZMQ_IMMEDIATE: Queue messages only to completed connections
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 

include/zmq.h

@@ -289,6 +289,7 @@ ZMQ_EXPORT int zmq_msg_set (zmq_msg_t *msg, int option, int optval);
 #define ZMQ_CONFLATE 54
 #define ZMQ_ZAP_DOMAIN 55
 #define ZMQ_ROUTER_HANDOVER 56
+#define ZMQ_TOS 57
 
 /*  Message options                                                           */
 #define ZMQ_MORE 1

src/ip.cpp

@@ -148,3 +148,18 @@ bool zmq::get_peer_ip_address (fd_t sockfd_, std::string &ip_addr_)
     ip_addr_ = host;
     return true;
 }
+
+
+void zmq::set_ip_type_of_service (fd_t s_, int iptos)
+{
+  (void) s_;
+
+  int rc = setsockopt(s_, IPPROTO_IP, IP_TOS,  &iptos, sizeof(iptos));
+
+#ifdef ZMQ_HAVE_WINDOWS
+    wsa_assert (rc != SOCKET_ERROR);
+#else
+    errno_assert (rc == 0);
+#endif
+
+}

src/ip.hpp

@@ -39,6 +39,9 @@ namespace zmq
     //  Socket sockfd_ must be connected. Returns true iff successful.
     bool get_peer_ip_address (fd_t sockfd_, std::string &ip_addr_);
 
+    // Sets the IP Type-Of-Service for the underlying socket
+    void set_ip_type_of_service (fd_t s_, int iptos);
+
 }
 
 #endif

src/options.cpp

@@ -33,6 +33,7 @@ zmq::options_t::options_t () :
     multicast_hops (1),
     sndbuf (0),
     rcvbuf (0),
+    tos (0),
     type (-1),
     linger (-1),
     reconnect_ivl (100),
@@ -125,6 +126,13 @@ int zmq::options_t::setsockopt (int option_, const void *optval_,
             }
             break;
 
+        case ZMQ_TOS:
+            if (is_int && value >= 0) {
+                tos = value;
+                return 0;
+            }
+            break;
+
         case ZMQ_LINGER:
             if (is_int && value >= -1) {
                 linger = value;
@@ -424,6 +432,12 @@ int zmq::options_t::getsockopt (int option_, void *optval_, size_t *optvallen_)
             }
             break;
 
+        case ZMQ_TOS:
+            if (is_int) {
+                *value = tos;
+                return 0;
+            }
+            break;
         case ZMQ_TYPE:
             if (is_int) {
                 *value = type;

src/options.hpp

@@ -66,6 +66,9 @@ namespace zmq
         int sndbuf;
         int rcvbuf;
 
+        // Type of service (containing DSCP and ECN socket options)
+        int tos;
+
         //  Socket type.
         int type;
 

src/tcp_connecter.cpp

@@ -223,6 +223,10 @@ int zmq::tcp_connecter_t::open ()
     if (addr->resolved.tcp_addr->family () == AF_INET6)
         enable_ipv4_mapping (s);
 
+    // Set the IP Type-Of-Service priority for this socket
+    if (options.tos != 0)
+        set_ip_type_of_service (s, options.tos);
+
     // Set the socket to non-blocking mode so that we get async connect().
     unblock_socket (s);
 
@@ -232,6 +236,10 @@ int zmq::tcp_connecter_t::open ()
     if (options.rcvbuf != 0)
         set_tcp_receive_buffer (s, options.rcvbuf);
 
+    // Set the IP Type-Of-Service for the underlying socket
+    if (options.tos != 0)
+        set_ip_type_of_service (s, options.tos);
+
     //  Connect to the remote peer.
     int rc = ::connect (
         s, addr->resolved.tcp_addr->addr (),

src/tcp_listener.cpp

@@ -188,6 +188,10 @@ int zmq::tcp_listener_t::set_address (const char *addr_)
     if (address.family () == AF_INET6)
         enable_ipv4_mapping (s);
 
+    // Set the IP Type-Of-Service for the underlying socket
+    if (options.tos != 0)
+        set_ip_type_of_service (s, options.tos);
+
     //  Set the socket buffer limits for the underlying socket.
     if (options.sndbuf != 0)
         set_tcp_send_buffer (s, options.sndbuf);
@@ -300,5 +304,9 @@ zmq::fd_t zmq::tcp_listener_t::accept ()
         }
     }
 
+    // Set the IP Type-Of-Service priority for this client socket
+    if (options.tos != 0)
+        set_ip_type_of_service (sock, options.tos);
+
     return sock;
 }

tests/Makefile.am

@@ -42,7 +42,8 @@ noinst_PROGRAMS = test_system \
                   test_issue_566 \
                   test_proxy \
                   test_abstract_ipc \
-                  test_many_sockets
+                  test_many_sockets \
+                  test_diffserv
 
 if !ON_MINGW
 noinst_PROGRAMS += test_shutdown_stress \
@@ -103,6 +104,7 @@ test_issue_566_SOURCES = test_issue_566.cpp
 test_proxy_SOURCES = test_proxy.cpp
 test_abstract_ipc_SOURCES = test_abstract_ipc.cpp
 test_many_sockets_SOURCES = test_many_sockets.cpp
+test_diffserv_SOURCES = test_diffserv.cpp
 if !ON_MINGW
 test_shutdown_stress_SOURCES = test_shutdown_stress.cpp
 test_pair_ipc_SOURCES = test_pair_ipc.cpp testutil.hpp

tests/test_diffserv.cpp

@@ -0,0 +1,70 @@
+/*
+    Copyright (c) 2007-2013 Contributors as noted in the AUTHORS file
+
+    This file is part of 0MQ.
+
+    0MQ is free software; you can redistribute it and/or modify it under
+    the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation; either version 3 of the License, or
+    (at your option) any later version.
+
+    0MQ is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "testutil.hpp"
+
+int main (void)
+{
+    int rc;
+    int tos = 0x28;
+    int o_tos;
+    size_t tos_size = sizeof(tos);
+
+    setup_test_environment();
+    void *ctx = zmq_ctx_new ();
+    assert (ctx);
+
+    void *sb = zmq_socket (ctx, ZMQ_PAIR);
+    assert (sb);
+    rc = zmq_setsockopt (sb, ZMQ_TOS, &tos, tos_size);
+    assert (rc == 0);
+    rc = zmq_bind (sb, "tcp://127.0.0.1:5560");
+    assert (rc == 0);
+    rc = zmq_getsockopt (sb, ZMQ_TOS, &o_tos, &tos_size);
+    assert (rc == 0);
+    assert (o_tos == tos);
+
+    void *sc = zmq_socket (ctx, ZMQ_PAIR);
+    assert (sc);
+    tos = 0x58;
+    rc = zmq_setsockopt (sc, ZMQ_TOS, &tos, tos_size);
+    assert (rc == 0);
+    rc = zmq_connect (sc, "tcp://127.0.0.1:5560");
+    assert (rc == 0);
+    rc = zmq_getsockopt (sc, ZMQ_TOS, &o_tos, &tos_size);
+    assert (rc == 0);
+    assert (o_tos == tos);
+
+    // Wireshark can be used to verify that the server socket is
+    // using DSCP 0x28 in packets to the client while the client
+    // is using 0x58 in packets to the server.
+    bounce (sb, sc);
+
+    rc = zmq_close (sc);
+    assert (rc == 0);
+
+    rc = zmq_close (sb);
+    assert (rc == 0);
+
+    rc = zmq_ctx_term (ctx);
+    assert (rc == 0);
+
+    return 0 ;
+
+}