client-kill management interface command, when issued on server, will

now send a RESTART message to client.

This feature is intended to make UDP clients respond the same as TCP
clients in the case where the server issues a RESTART message in
order to force the client to reconnect and pull a new options/route
list.


git-svn-id: http://svn.openvpn.net/projects/openvpn/branches/BETA21/openvpn@5021 e7ae566f-a301-0410-adde-c780ea21d3b5

forward.c

@@ -157,6 +157,8 @@ check_incoming_control_channel_dowork (struct context *c)
 	    receive_auth_failed (c, &buf);
 	  else if (buf_string_match_head_str (&buf, "PUSH_"))
 	    incoming_push_message (c, &buf);
+	  else if (buf_string_match_head_str (&buf, "RESTART"))
+	    server_pushed_restart (c, &buf);
 	  else
 	    msg (D_PUSH_ERRORS, "WARNING: Received unknown control message: %s", BSTR (&buf));
 	}
@@ -181,7 +183,7 @@ check_push_request_dowork (struct context *c)
   event_timeout_modify_wakeup (&c->c2.push_request_interval, 5);
 }
 
-#endif
+#endif /* P2MP */
 
 /*
  * Things that need to happen immediately after connection initiation should go here.
@@ -328,15 +330,16 @@ check_server_poll_timeout_dowork (struct context *c)
 }
 
 /*
- * Schedule a SIGTERM n_seconds from now.
+ * Schedule a signal n_seconds from now.
  */
 void
-schedule_exit (struct context *c, const int n_seconds)
+schedule_exit (struct context *c, const int n_seconds, const int signal)
 {
   tls_set_single_session (c->c2.tls_multi);
   update_time ();
   reset_coarse_timers (c);
   event_timeout_init (&c->c2.scheduled_exit, n_seconds, now);
+  c->c2.scheduled_exit_signal = signal;
   msg (D_SCHED_EXIT, "Delayed exit in %d seconds", n_seconds);
 }
 
@@ -346,7 +349,7 @@ schedule_exit (struct context *c, const int n_seconds)
 void
 check_scheduled_exit_dowork (struct context *c)
 {
-  c->sig->signal_received = SIGTERM;
+  c->sig->signal_received = c->c2.scheduled_exit_signal;
   c->sig->signal_text = "delayed-exit";
 }
 

forward.h

@@ -80,7 +80,7 @@ bool send_control_channel_string (struct context *c, const char *str, int msglev
 void process_ipv4_header (struct context *c, unsigned int flags, struct buffer *buf);
 
 #if P2MP
-void schedule_exit (struct context *c, const int n_seconds);
+void schedule_exit (struct context *c, const int n_seconds, const int signal);
 #endif
 
 #endif /* FORWARD_H */

multi.c

@@ -2539,7 +2539,7 @@ management_kill_by_cid (void *arg, const unsigned long cid)
   struct multi_instance *mi = lookup_by_cid (m, cid);
   if (mi)
     {
-      multi_signal_instance (m, mi, SIGTERM);
+      send_restart (&mi->context); /* was: multi_signal_instance (m, mi, SIGTERM); */
       return true;
     }
   else

openvpn.h

@@ -436,6 +436,7 @@ struct context_2
   struct event_timeout server_poll_interval;
 
   struct event_timeout scheduled_exit;
+  int scheduled_exit_signal;
 #endif
 
   /* packet filter */

push.c

@@ -72,7 +72,22 @@ receive_auth_failed (struct context *c, const struct buffer *buffer)
     }
 }
 
+/*
+ * Act on received restart message from server
+ */
+void
+server_pushed_restart (struct context *c, const struct buffer *buffer)
+{
+  if (c->options.pull)
+    {
+      msg (D_STREAM_ERRORS, "Connection reset command was pushed by server");
+      c->sig->signal_received = SIGUSR1; /* SOFT-SIGUSR1 -- server-pushed connection reset */
+      c->sig->signal_text = "server-pushed-connection-reset";
+    }
+}
+
 #if P2MP_SERVER
+
 /*
  * Send auth failed message from server to client.
  */
@@ -83,7 +98,7 @@ send_auth_failed (struct context *c, const char *client_reason)
   static const char auth_failed[] = "AUTH_FAILED";
   size_t len;
 
-  schedule_exit (c, c->options.scheduled_exit_interval);
+  schedule_exit (c, c->options.scheduled_exit_interval, SIGTERM);
 
   len = (client_reason ? strlen(client_reason)+1 : 0) + sizeof(auth_failed);
   if (len > TLS_CHANNEL_BUF_SIZE)
@@ -99,6 +114,17 @@ send_auth_failed (struct context *c, const char *client_reason)
 
   gc_free (&gc);
 }
+
+/*
+ * Send restart message from server to client.
+ */
+void
+send_restart (struct context *c)
+{
+  schedule_exit (c, c->options.scheduled_exit_interval, SIGTERM);
+  send_control_channel_string (c, "RESTART", D_PUSH);
+}
+
 #endif
 
 /*

push.h

@@ -49,6 +49,8 @@ bool send_push_request (struct context *c);
 
 void receive_auth_failed (struct context *c, const struct buffer *buffer);
 
+void server_pushed_restart (struct context *c, const struct buffer *buffer);
+
 #if P2MP_SERVER
 
 void clone_push_list (struct options *o);
@@ -64,6 +66,8 @@ void remove_iroutes_from_push_route_list (struct options *o);
 
 void send_auth_failed (struct context *c, const char *client_reason);
 
+void send_restart (struct context *c);
+
 #endif
 #endif
 #endif