Attempt at rational signal handling when in the

management hold state.

During management hold, ignore SIGUSR1/SIGHUP signals
thrown with the "signal" command.

Also, "signal" command will now apply remapping as
specified with the --remap-usr1 option.

When a signal entered using the "signal" command from a management
hold is ignored, output:

>HOLD:Waiting for hold release


git-svn-id: http://svn.openvpn.net/projects/openvpn/branches/BETA21/openvpn@1458 e7ae566f-a301-0410-adde-c780ea21d3b5

init.c

@@ -1225,6 +1225,7 @@ socket_restart_pause (struct context *c)
     sec = c->persist.restart_sleep_seconds;
   c->persist.restart_sleep_seconds = 0;
 
+  /* do managment hold on context restart, i.e. second, third, fourth, etc. initialization */
   if (do_hold (NULL))
     sec = 0;
 
@@ -1244,7 +1245,7 @@ do_startup_pause (struct context *c)
   if (!c->first_time)
     socket_restart_pause (c);
   else
-    do_hold (NULL);
+    do_hold (NULL); /* do management hold on first context initialization */
 }
 
 /*
@@ -2456,7 +2457,8 @@ open_management (struct context *c)
 			       c->options.management_state_buffer_size,
 			       c->options.management_hold,
 			       c->options.management_client,
-			       c->options.management_write_peer_info_file))
+			       c->options.management_write_peer_info_file,
+			       c->options.remap_sigusr1))
 	    {
 	      management_set_state (management,
 				    OPENVPN_STATE_CONNECTING,
@@ -2465,7 +2467,7 @@ open_management (struct context *c)
 				    (in_addr_t)0);
 	    }
 
-	  /* possible wait */
+	  /* initial management hold, called early, before first context initialization */
 	  do_hold (c);
 	  if (IS_SIG (c))
 	    {

manage.c

@@ -277,14 +277,49 @@ virtual_output_callback_func (void *arg, const unsigned int flags, const char *s
     }
 }
 
+/*
+ * Given a signal, return the signal with possible remapping applied,
+ * or -1 if the signal should be ignored.
+ */
+static int
+man_mod_signal (const struct management *man, const int signum)
+{
+  const unsigned int flags = man->settings.mansig;
+  int s = signum;
+  if (s == SIGUSR1)
+    {
+      if (flags & MANSIG_MAP_USR1_TO_HUP)
+	s = SIGHUP;
+      if (flags & MANSIG_MAP_USR1_TO_TERM)
+	s = SIGTERM;
+    }
+  if (flags & MANSIG_IGNORE_USR1_HUP)
+    {
+      if (s == SIGHUP || s == SIGUSR1)
+	s = -1;
+    }
+  return s;
+}
+
 static void
 man_signal (struct management *man, const char *name)
 {
   const int sig = parse_signal (name);
   if (sig >= 0)
     {
-      throw_signal (sig);
-      msg (M_CLIENT, "SUCCESS: signal %s thrown", signal_name (sig, true));
+      const int sig_mod = man_mod_signal (man, sig);
+      if (sig_mod >= 0)
+	{
+	  throw_signal (sig_mod);
+	  msg (M_CLIENT, "SUCCESS: signal %s thrown", signal_name (sig_mod, true));
+	}
+      else
+	{
+	  if (man->persist.special_state_msg)
+	    msg (M_CLIENT, "%s", man->persist.special_state_msg);
+	  else
+	    msg (M_CLIENT, "ERROR: signal '%s' is currently ignored", name);
+	}
     }
   else
     {
@@ -1276,7 +1311,8 @@ man_settings_init (struct man_settings *ms,
 		   const int state_buffer_size,
 		   const bool hold,
 		   const bool connect_as_client,
-		   const char *write_peer_info_file)
+		   const char *write_peer_info_file,
+		   const int remap_sigusr1)
 {
   if (!ms->defined)
     {
@@ -1340,6 +1376,14 @@ man_settings_init (struct man_settings *ms,
       ms->echo_buffer_size = echo_buffer_size;
       ms->state_buffer_size = state_buffer_size;
 
+      /*
+       * Set remap sigusr1 flags
+       */
+      if (remap_sigusr1 == SIGHUP)
+	ms->mansig |= MANSIG_MAP_USR1_TO_HUP;
+      else if (remap_sigusr1 == SIGTERM)
+	ms->mansig |= MANSIG_MAP_USR1_TO_TERM;
+
       ms->defined = true;
     }
 }
@@ -1440,7 +1484,8 @@ management_open (struct management *man,
 		 const int state_buffer_size,
 		 const bool hold,
 		 const bool connect_as_client,
-		 const char *write_peer_info_file)
+		 const char *write_peer_info_file,
+		 const int remap_sigusr1)
 {
   bool ret = false;
 
@@ -1459,7 +1504,8 @@ management_open (struct management *man,
 		     state_buffer_size,
 		     hold,
 		     connect_as_client,
-		     write_peer_info_file);
+		     write_peer_info_file,
+		     remap_sigusr1);
 
   /*
    * The log is initially sized to MANAGEMENT_LOG_HISTORY_INITIAL_SIZE,
@@ -2052,6 +2098,7 @@ management_hold (struct management *man)
 
       man->persist.standalone_disabled = false; /* This is so M_CLIENT messages will be correctly passed through msg() */
       man->persist.special_state_msg = NULL;
+      man->settings.mansig |= MANSIG_IGNORE_USR1_HUP;
 
       man_wait_for_client_connection (man, &signal_received, 0, MWCC_HOLD_WAIT);
 
@@ -2072,6 +2119,7 @@ management_hold (struct management *man)
       /* revert state */
       man->persist.standalone_disabled = standalone_disabled_save;
       man->persist.special_state_msg = NULL;
+      man->settings.mansig &= ~MANSIG_IGNORE_USR1_HUP;
 
       return true;
     }

manage.h

@@ -207,6 +207,12 @@ struct man_settings {
   bool hold;
   bool connect_as_client;
   char *write_peer_info_file;
+
+/* flags for handling the management interface "signal" command */
+# define MANSIG_IGNORE_USR1_HUP  (1<<0)
+# define MANSIG_MAP_USR1_TO_HUP  (1<<1)
+# define MANSIG_MAP_USR1_TO_TERM (1<<2)
+  unsigned int mansig;
 };
 
 /* up_query modes */
@@ -276,7 +282,8 @@ bool management_open (struct management *man,
 		      const int state_buffer_size,
 		      const bool hold,
 		      const bool connect_as_client,
-		      const char *write_peer_info_file);
+		      const char *write_peer_info_file,
+		      const int remap_sigusr1);
 
 void management_close (struct management *man);
 

openvpn.c

@@ -107,8 +107,6 @@ main (int argc, char *argv[])
   return 1;
 #endif
 
-  pre_init_signal_catch ();
-
   CLEAR (c);
 
   /* signify first time for components which can
@@ -124,6 +122,9 @@ main (int argc, char *argv[])
        */
       do
 	{
+	  /* enter pre-initialization mode with regard to signal handling */
+	  pre_init_signal_catch ();
+
 	  /* zero context struct but leave first_time member alone */
 	  context_clear_all_except_first_time (&c);