Issue #1017: add ZMQ_HANDSHAKE_IVL time limit on connection handshake

doc/zmq_getsockopt.txt

@@ -164,6 +164,22 @@ Default value:: N/A
 Applicable socket types:: all
 
 
+ZMQ_HANDSHAKE_IVL: Retrieve maximum handshake interval
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+The 'ZMQ_HANDSHAKE_IVL' option shall retrieve the maximum handshake interval
+for the specified 'socket'. Handshaking is the exchange of socket configuration
+information (socket type, identity, security) that occurs when a connection
+is first opened, only for connection-oriented transports. If handshaking does
+not complete within the configured time, the connection shall be closed.
+The value 0 means no handshake time limit.
+
+[horizontal]
+Option value type:: int
+Option value unit:: milliseconds
+Default value:: 30000
+Applicable socket types:: all but ZMQ_STREAM, only for connection-oriented transports
+
+
 ZMQ_IDENTITY: Retrieve socket identity
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 The 'ZMQ_IDENTITY' option shall retrieve the identity of the specified 'socket'.

doc/zmq_setsockopt.txt

@@ -170,6 +170,22 @@ Default value:: NULL
 Applicable socket types:: all, when using TCP transport
 
 
+ZMQ_HANDSHAKE_IVL: Set maximum handshake interval
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+The 'ZMQ_HANDSHAKE_IVL' option shall set the maximum handshake interval for
+the specified 'socket'. Handshaking is the exchange of socket configuration
+information (socket type, identity, security) that occurs when a connection
+is first opened, only for connection-oriented transports. If handshaking does
+not complete within the configured time, the connection shall be closed.
+The value 0 means no handshake time limit.
+
+[horizontal]
+Option value type:: int
+Option value unit:: milliseconds
+Default value:: 30000
+Applicable socket types:: all but ZMQ_STREAM, only for connection-oriented transports
+
+
 ZMQ_IDENTITY: Set socket identity
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 The 'ZMQ_IDENTITY' option shall set the identity of the specified 'socket'

include/zmq.h

@@ -300,6 +300,7 @@ ZMQ_EXPORT const char *zmq_msg_gets (zmq_msg_t *msg, const char *property);
 #define ZMQ_GSSAPI_PRINCIPAL 63
 #define ZMQ_GSSAPI_SERVICE_PRINCIPAL 64
 #define ZMQ_GSSAPI_PLAINTEXT 65
+#define ZMQ_HANDSHAKE_IVL 66
 
 /*  Message options                                                           */
 #define ZMQ_MORE 1

src/options.cpp

@@ -55,7 +55,8 @@ zmq::options_t::options_t () :
     as_server (0),
     gss_plaintext (false),
     socket_id (0),
-    conflate (false)
+    conflate (false),
+    handshake_ivl (30000)
 {
 }
 
@@ -435,6 +436,13 @@ int zmq::options_t::setsockopt (int option_, const void *optval_,
             }
             break;
 	
+        case ZMQ_HANDSHAKE_IVL:
+            if (is_int && value >= 0) {
+                handshake_ivl = value;
+                return 0;
+            }
+            break;
+
 
         default:
             break;
@@ -746,6 +754,13 @@ int zmq::options_t::getsockopt (int option_, void *optval_, size_t *optvallen_)
             }
             break;
  
+        case ZMQ_HANDSHAKE_IVL:
+            if (is_int) {
+                *value = handshake_ivl;
+                return 0;
+            }
+            break;
+
 
 	}
     errno = EINVAL;

src/options.hpp

@@ -171,6 +171,11 @@ namespace zmq
         //  Cannot receive multi-part messages.
         //  Ignores hwm
         bool conflate;
+
+        //  If connection handshake is not done after this many milliseconds,
+        //  close socket.  Default is 30 secs.  0 means no handshake timeout.
+        int handshake_ivl;
+
     };
 }
 

src/stream_engine.cpp

@@ -80,6 +80,7 @@ zmq::stream_engine_t::stream_engine_t (fd_t fd_, const options_t &options_,
     mechanism (NULL),
     input_stopped (false),
     output_stopped (false),
+    has_handshake_timer (false),
     socket (NULL)
 {
     int rc = tx_msg.init ();
@@ -197,6 +198,9 @@ void zmq::stream_engine_t::plug (io_thread_t *io_thread_,
         session->flush ();
     }
     else {
+        // start optional timer, to prevent handshake hanging on no input
+        set_handshake_timer ();
+
         //  Send the 'length' and 'flags' fields of the identity message.
         //  The 'length' field is encoded in the long format.
         outpos = greeting_send;
@@ -217,6 +221,12 @@ void zmq::stream_engine_t::unplug ()
     zmq_assert (plugged);
     plugged = false;
 
+    //  Cancel all timers.
+    if (has_handshake_timer) {
+        cancel_timer (handshake_timer_id);
+        has_handshake_timer = false;
+    }
+
     //  Cancel all fd subscriptions.
     if (!io_error)
         rm_fd (handle);
@@ -631,6 +641,11 @@ bool zmq::stream_engine_t::handshake ()
     //  Switch into the normal message flow.
     handshaking = false;
 
+    if (has_handshake_timer) {
+        cancel_timer (handshake_timer_id);
+        has_handshake_timer = false;
+    }
+
     return true;
 }
 
@@ -969,3 +984,22 @@ int zmq::stream_engine_t::read (void *data_, size_t size_)
 
 #endif
 }
+
+void zmq::stream_engine_t::set_handshake_timer ()
+{
+    zmq_assert (!has_handshake_timer);
+
+    if (!options.raw_sock && options.handshake_ivl > 0) {
+        add_timer (options.handshake_ivl, handshake_timer_id);
+        has_handshake_timer = true;
+    }
+}
+
+void zmq::stream_engine_t::timer_event (int id_)
+{
+    zmq_assert (id_ == handshake_timer_id);
+    has_handshake_timer = false;
+
+    //  handshake timer expired before handshake completed, so engine fails
+    error ();
+}

src/stream_engine.hpp

@@ -68,6 +68,7 @@ namespace zmq
         //  i_poll_events interface implementation.
         void in_event ();
         void out_event ();
+        void timer_event (int id_);
 
     private:
 
@@ -114,6 +115,8 @@ namespace zmq
         size_t add_property (unsigned char *ptr,
             const char *name, const void *value, size_t value_len);
 
+        void set_handshake_timer();
+
         //  Underlying socket.
         fd_t s;
 
@@ -187,6 +190,12 @@ namespace zmq
         //  True iff the engine doesn't have any message to encode.
         bool output_stopped;
 
+        //  ID of the handshake timer
+        enum {handshake_timer_id = 0x40};
+
+        //  True is linger timer is running.
+        bool has_handshake_timer;
+
         // Socket
         zmq::socket_base_t *socket;
 

tests/Makefile.am

@@ -25,6 +25,7 @@ noinst_PROGRAMS = test_system \
                   test_stream \
                   test_stream_empty \
                   test_stream_disconnect \
+                  test_stream_timeout \
                   test_disconnect_inproc \
                   test_ctx_options \
                   test_ctx_destroy \

tests/test_stream_timeout.cpp

+/*
+    Copyright (c) 2007-2014 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"
+
+//  Read one event off the monitor socket; return value and address
+//  by reference, if not null, and event number by value. Returns -1
+//  in case of error.
+
+static int
+get_monitor_event (void *monitor, int *value, char **address)
+{
+    //  First frame in message contains event number and value
+    zmq_msg_t msg; 
+    zmq_msg_init (&msg);
+    if (zmq_msg_recv (&msg, monitor, 0) == -1)
+        return -1;              //  Interruped, presumably
+    assert (zmq_msg_more (&msg));
+    
+    uint8_t *data = (uint8_t *) zmq_msg_data (&msg);
+    uint16_t event = *(uint16_t *) (data);
+    if (value)
+        *value = *(uint32_t *) (data + 2);
+
+    //  Second frame in message contains event address
+    zmq_msg_init (&msg);
+    if (zmq_msg_recv (&msg, monitor, 0) == -1)
+        return -1;              //  Interruped, presumably
+    assert (!zmq_msg_more (&msg));
+    
+    if (address) {
+        uint8_t *data = (uint8_t *) zmq_msg_data (&msg);
+        size_t size = zmq_msg_size (&msg);
+        *address = (char *) malloc (size + 1);
+        memcpy (*address, data, size);
+        *address [size] = 0;
+    }
+    return event;
+}
+
+static void
+test_stream_handshake_timeout_accept (void)
+{
+    int rc;
+
+    //  Set up our context and sockets
+    void *ctx = zmq_ctx_new ();
+    assert (ctx);
+
+    //  We use this socket in raw mode, to make a connection and send nothing
+    void *stream = zmq_socket (ctx, ZMQ_STREAM);
+    assert (stream);
+
+    int zero = 0;
+    rc = zmq_setsockopt (stream, ZMQ_LINGER, &zero, sizeof (zero));
+    assert (rc == 0);
+    rc = zmq_connect (stream, "tcp://localhost:5557");
+    assert (rc == 0);
+
+    //  We'll be using this socket to test TCP stream handshake timeout
+    void *dealer = zmq_socket (ctx, ZMQ_DEALER);
+    assert (dealer);
+    rc = zmq_setsockopt (dealer, ZMQ_LINGER, &zero, sizeof (zero));
+    assert (rc == 0);
+    int val, tenth = 100;
+    size_t vsize = sizeof(val);
+
+    // check for the expected default handshake timeout value - 30 sec
+    rc = zmq_getsockopt (dealer, ZMQ_HANDSHAKE_IVL, &val, &vsize);
+    assert (rc == 0);
+    assert (vsize == sizeof(val));
+    assert (val == 30000);
+    // make handshake timeout faster - 1/10 sec
+    rc = zmq_setsockopt (dealer, ZMQ_HANDSHAKE_IVL, &tenth, sizeof (tenth));
+    assert (rc == 0);
+    vsize = sizeof(val);
+    // make sure zmq_setsockopt changed the value
+    rc = zmq_getsockopt (dealer, ZMQ_HANDSHAKE_IVL, &val, &vsize);
+    assert (rc == 0);
+    assert (vsize == sizeof(val));
+    assert (val == tenth);
+
+    //  Create and connect a socket for collecting monitor events on dealer
+    void *dealer_mon = zmq_socket (ctx, ZMQ_PAIR);
+    assert (dealer_mon);
+
+    rc = zmq_socket_monitor (dealer, "inproc://monitor-dealer",
+          ZMQ_EVENT_CONNECTED | ZMQ_EVENT_DISCONNECTED | ZMQ_EVENT_ACCEPTED);
+    assert (rc == 0);
+
+    //  Connect to the inproc endpoint so we'll get events
+    rc = zmq_connect (dealer_mon, "inproc://monitor-dealer");
+    assert (rc == 0);
+
+    // bind dealer socket to accept connection from non-sending stream socket
+    rc = zmq_bind (dealer, "tcp://127.0.0.1:5557");
+    assert (rc == 0);
+
+    // we should get ZMQ_EVENT_ACCEPTED and then ZMQ_EVENT_DISCONNECTED
+    int event = get_monitor_event (dealer_mon, NULL, NULL);
+    assert (event == ZMQ_EVENT_ACCEPTED);
+    event = get_monitor_event (dealer_mon, NULL, NULL);
+    assert (event == ZMQ_EVENT_DISCONNECTED);
+
+    rc = zmq_close (dealer);
+    assert (rc == 0);
+
+    rc = zmq_close (dealer_mon);
+    assert (rc == 0);
+
+    rc = zmq_close (stream);
+    assert (rc == 0);
+
+    rc = zmq_ctx_term (ctx);
+    assert (rc == 0);
+}
+
+static void
+test_stream_handshake_timeout_connect (void)
+{
+    int rc;
+
+    //  Set up our context and sockets
+    void *ctx = zmq_ctx_new ();
+    assert (ctx);
+
+    //  We use this socket in raw mode, to accept a connection and send nothing
+    void *stream = zmq_socket (ctx, ZMQ_STREAM);
+    assert (stream);
+
+    int zero = 0;
+    rc = zmq_setsockopt (stream, ZMQ_LINGER, &zero, sizeof (zero));
+    assert (rc == 0);
+    rc = zmq_bind (stream, "tcp://127.0.0.1:5556");
+    assert (rc == 0);
+
+    //  We'll be using this socket to test TCP stream handshake timeout
+    void *dealer = zmq_socket (ctx, ZMQ_DEALER);
+    assert (dealer);
+    rc = zmq_setsockopt (dealer, ZMQ_LINGER, &zero, sizeof (zero));
+    assert (rc == 0);
+    int val, tenth = 100;
+    size_t vsize = sizeof(val);
+
+    // check for the expected default handshake timeout value - 30 sec
+    rc = zmq_getsockopt (dealer, ZMQ_HANDSHAKE_IVL, &val, &vsize);
+    assert (rc == 0);
+    assert (vsize == sizeof(val));
+    assert (val == 30000);
+    // make handshake timeout faster - 1/10 sec
+    rc = zmq_setsockopt (dealer, ZMQ_HANDSHAKE_IVL, &tenth, sizeof (tenth));
+    assert (rc == 0);
+    vsize = sizeof(val);
+    // make sure zmq_setsockopt changed the value
+    rc = zmq_getsockopt (dealer, ZMQ_HANDSHAKE_IVL, &val, &vsize);
+    assert (rc == 0);
+    assert (vsize == sizeof(val));
+    assert (val == tenth);
+
+    //  Create and connect a socket for collecting monitor events on dealer
+    void *dealer_mon = zmq_socket (ctx, ZMQ_PAIR);
+    assert (dealer_mon);
+
+    rc = zmq_socket_monitor (dealer, "inproc://monitor-dealer",
+          ZMQ_EVENT_CONNECTED | ZMQ_EVENT_DISCONNECTED | ZMQ_EVENT_ACCEPTED);
+    assert (rc == 0);
+
+    //  Connect to the inproc endpoint so we'll get events
+    rc = zmq_connect (dealer_mon, "inproc://monitor-dealer");
+    assert (rc == 0);
+
+    // connect dealer socket to non-sending stream socket
+    rc = zmq_connect (dealer, "tcp://localhost:5556");
+    assert (rc == 0);
+
+    // we should get ZMQ_EVENT_CONNECTED and then ZMQ_EVENT_DISCONNECTED
+    int event = get_monitor_event (dealer_mon, NULL, NULL);
+    assert (event == ZMQ_EVENT_CONNECTED);
+    event = get_monitor_event (dealer_mon, NULL, NULL);
+    assert (event == ZMQ_EVENT_DISCONNECTED);
+
+    rc = zmq_close (dealer);
+    assert (rc == 0);
+
+    rc = zmq_close (dealer_mon);
+    assert (rc == 0);
+
+    rc = zmq_close (stream);
+    assert (rc == 0);
+
+    rc = zmq_ctx_term (ctx);
+    assert (rc == 0);
+}
+
+int main (void)
+{
+    setup_test_environment();
+    test_stream_handshake_timeout_accept ();
+    test_stream_handshake_timeout_connect ();
+}