New function IRC_KillClient() to kill clients

The old local function Kill_Nick() in irc.c has been an ugly hack. This
patch implements a generic function for killing clients.

Adjust all callers of Kill_Nick() and respect the return code!

src/ngircd/irc-login.c

@@ -1,6 +1,6 @@
 /*
  * ngIRCd -- The Next Generation IRC Daemon
- * Copyright (c)2001-2012 Alexander Barton (alex@barton.de) and Contributors.
+ * Copyright (c)2001-2013 Alexander Barton (alex@barton.de) and Contributors.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -39,7 +39,6 @@
 #include "exp.h"
 #include "irc-login.h"
 
-static void Kill_Nick PARAMS((char *Nick, char *Reason));
 static void Change_Nick PARAMS((CLIENT * Origin, CLIENT * Target, char *NewNick,
 				bool InformClient));
 
@@ -303,17 +302,21 @@ IRC_NICK( CLIENT *Client, REQUEST *Req )
 			 * the new nick is already present on this server:
 			 * the new and the old one have to be disconnected now.
 			 */
-			Log( LOG_ERR, "Server %s introduces already registered nick \"%s\"!", Client_ID( Client ), Req->argv[0] );
+			Log(LOG_ERR,
-			Kill_Nick( Req->argv[0], "Nick collision" );
+			    "Server %s introduces already registered nick \"%s\"!",
-			return CONNECTED;
+			    Client_ID(Client), Req->argv[0]);
+			return IRC_KillClient(Client, NULL, Req->argv[0],
+					      "Nick collision");
 		}
 
 		/* Find the Server this client is connected to */
 		intr_c = Client_GetFromToken(Client, token);
 		if (!intr_c) {
-			Log( LOG_ERR, "Server %s introduces nick \"%s\" on unknown server!?", Client_ID( Client ), Req->argv[0] );
+			Log(LOG_ERR,
-			Kill_Nick( Req->argv[0], "Unknown server" );
+			    "Server %s introduces nick \"%s\" on unknown server!?",
-			return CONNECTED;
+			    Client_ID(Client), Req->argv[0]);
+			return IRC_KillClient(Client, NULL, Req->argv[0],
+					      "Unknown server");
 		}
 
 		c = Client_NewRemoteUser(intr_c, nick, hops, user, hostname,
@@ -324,8 +327,8 @@ IRC_NICK( CLIENT *Client, REQUEST *Req )
 			Log(LOG_ALERT,
 			    "Can't create client structure! (on connection %d)",
 			    Client_Conn(Client));
-			Kill_Nick(Req->argv[0], "Server error");
+			return IRC_KillClient(Client, NULL, Req->argv[0],
-			return CONNECTED;
+					      "Server error");
 		}
 
 		/* RFC 2813: client is now fully registered, inform all the
@@ -536,19 +539,19 @@ IRC_SERVICE(CLIENT *Client, REQUEST *Req)
 	c = Client_Search(nick);
 	if(c) {
 		/* Nickname collision: disconnect (KILL) both clients! */
-		Log(LOG_ERR, "Server %s introduces already registered service \"%s\"!",
+		Log(LOG_ERR,
+		    "Server %s introduces already registered service \"%s\"!",
 		    Client_ID(Client), nick);
-		Kill_Nick(nick, "Nick collision");
+		return IRC_KillClient(Client, NULL, nick, "Nick collision");
-		return CONNECTED;
 	}
 
 	/* Get the server to which the service is connected */
 	intr_c = Client_GetFromToken(Client, token);
 	if (! intr_c) {
-		Log(LOG_ERR, "Server %s introduces service \"%s\" on unknown server!?",
+		Log(LOG_ERR,
+		    "Server %s introduces service \"%s\" on unknown server!?",
 		    Client_ID(Client), nick);
-		Kill_Nick(nick, "Unknown server");
+		return IRC_KillClient(Client, NULL, nick, "Unknown server");
-		return CONNECTED;
 	}
 
 	/* Get user and host name */
@@ -577,10 +580,10 @@ IRC_SERVICE(CLIENT *Client, REQUEST *Req)
 	if (! c) {
 		/* Couldn't create client structure, so KILL the service to
 		 * keep network status consistent ... */
-		Log(LOG_ALERT, "Can't create client structure! (on connection %d)",
+		Log(LOG_ALERT,
+		    "Can't create client structure! (on connection %d)",
 		    Client_Conn(Client));
-		Kill_Nick(nick, "Server error");
+		return IRC_KillClient(Client, NULL, nick, "Server error");
-		return CONNECTED;
 	}
 
 	Client_Introduce(Client, c, CLIENT_SERVICE);
@@ -855,31 +858,6 @@ IRC_PONG(CLIENT *Client, REQUEST *Req)
 	return CONNECTED;
 } /* IRC_PONG */
 
-/**
- * Kill all users with a specific nickname in the network.
- *
- * @param Nick Nickname.
- * @param Reason Reason for the KILL.
- */
-static void
-Kill_Nick(char *Nick, char *Reason)
-{
-	REQUEST r;
-
-	assert (Nick != NULL);
-	assert (Reason != NULL);
-
-	r.prefix = NULL;
-	r.argv[0] = Nick;
-	r.argv[1] = Reason;
-	r.argc = 2;
-
-	Log(LOG_ERR, "User(s) with nick \"%s\" will be disconnected: %s!",
-	    Nick, Reason);
-
-	IRC_KILL(Client_ThisServer(), &r);
-} /* Kill_Nick */
-
 /**
  * Change the nickname of a client.
  *

src/ngircd/irc.c

@@ -128,9 +128,8 @@ IRC_ERROR(CLIENT *Client, REQUEST *Req)
 GLOBAL bool
 IRC_KILL(CLIENT *Client, REQUEST *Req)
 {
-	CLIENT *prefix, *c;
+	CLIENT *prefix;
-	char reason[COMMAND_LEN], *msg;
+	char reason[COMMAND_LEN];
-	CONN_ID my_conn, conn;
 
 	assert (Client != NULL);
 	assert (Req != NULL);
@@ -166,59 +165,8 @@ IRC_KILL(CLIENT *Client, REQUEST *Req)
 	else
 		strlcpy(reason, Req->argv[1], sizeof(reason));
 
-	/* Inform other servers */
+	return IRC_KillClient(Client, prefix, Req->argv[0], reason);
-	IRC_WriteStrServersPrefix(Client, prefix, "KILL %s :%s",
+}
-				  Req->argv[0], reason);
-
-	/* Save ID of this connection */
-	my_conn = Client_Conn( Client );
-
-	/* Do we host such a client? */
-	c = Client_Search( Req->argv[0] );
-	if (c) {
-		if (Client_Type(c) != CLIENT_USER
-		    && Client_Type(c) != CLIENT_GOTNICK) {
-			/* Target of this KILL is not a regular user, this is
-			 * invalid! So we ignore this case if we received a
-			 * regular KILL from the network and try to kill the
-			 * client/connection anyway (but log an error!) if the
-			 * origin is the local server. */
-
-			if (Client != Client_ThisServer()) {
-				/* Invalid KILL received from remote */
-				if (Client_Type(c) == CLIENT_SERVER)
-					msg = ERR_CANTKILLSERVER_MSG;
-				else
-					msg = ERR_NOPRIVILEGES_MSG;
-				return IRC_WriteErrClient(Client, msg,
-							  Client_ID(Client));
-			}
-
-			Log(LOG_ERR,
-			    "Got KILL for invalid client type: %d, \"%s\"!",
-			    Client_Type( c ), Req->argv[0] );
-		}
-
-		/* Kill the client NOW:
-		 *  - Close the local connection (if there is one),
-		 *  - Destroy the CLIENT structure for remote clients.
-		 * Note: Conn_Close() removes the CLIENT structure as well. */
-		conn = Client_Conn( c );
-		if(conn > NONE)
-			Conn_Close(conn, NULL, reason, true);
-		else
-			Client_Destroy(c, NULL, reason, false);
-	}
-	else
-		Log(LOG_NOTICE, "Client with nick \"%s\" is unknown here.",
-		    Req->argv[0]);
-
-	/* Are we still connected or were we killed, too? */
-	if (my_conn > NONE && Conn_GetClient(my_conn))
-		return CONNECTED;
-	else
-		return DISCONNECTED;
-} /* IRC_KILL */
 
 /**
  * Handler for the IRC "NOTICE" command.
@@ -376,6 +324,81 @@ IRC_HELP(CLIENT *Client, REQUEST *Req)
 	return CONNECTED;
 } /* IRC_HELP */
 
+/**
+ * Kill an client identified by its nick name.
+ *
+ * Please note that after killig a client, its CLIENT cond CONNECTION
+ * structures are invalid. So the caller must make sure on its own not to
+ * access data of probably killed clients after calling this function!
+ *
+ * @param Client The client from which the command leading to the KILL has
+ *		been received, or NULL. The KILL will no be forwarded in this
+ *		direction. Only relevant when From is set, too.
+ * @param From The client from which the command originated, or NULL for
+		the local server.
+ * @param Nick The nick name to kill.
+ * @param Reason Text to send as reason to the client and other servers.
+ */
+GLOBAL bool
+IRC_KillClient(CLIENT *Client, CLIENT *From, const char *Nick, const char *Reason)
+{
+	const char *msg;
+	CONN_ID my_conn, conn;
+	CLIENT *c;
+
+	/* Inform other servers */
+	IRC_WriteStrServersPrefix(From ? Client : NULL,
+				  From ? From : Client_ThisServer(),
+				  "KILL %s :%s", Nick, Reason);
+
+	/* Do we know such a client? */
+	c = Client_Search(Nick);
+	if (!c) {
+		LogDebug("Client with nick \"%s\" is unknown here.", Nick);
+		return CONNECTED;
+	}
+
+	if (Client_Type(c) != CLIENT_USER && Client_Type(c) != CLIENT_GOTNICK) {
+		/* Target of this KILL is not a regular user, this is
+		 * invalid! So we ignore this case if we received a
+		 * regular KILL from the network and try to kill the
+		 * client/connection anyway (but log an error!) if the
+		 * origin is the local server. */
+
+		if (Client != Client_ThisServer()) {
+			/* Invalid KILL received from remote */
+			if (Client_Type(c) == CLIENT_SERVER)
+				msg = ERR_CANTKILLSERVER_MSG;
+			else
+				msg = ERR_NOPRIVILEGES_MSG;
+			return IRC_WriteErrClient(Client, msg, Client_ID(Client));
+		}
+
+		Log(LOG_ERR,
+		    "Got KILL for invalid client type: %d, \"%s\"!",
+		    Client_Type(c), Nick);
+	}
+
+	/* Save ID of this connection */
+	my_conn = Client_Conn(Client);
+
+	/* Kill the client NOW:
+	 *  - Close the local connection (if there is one),
+	 *  - Destroy the CLIENT structure for remote clients.
+	 * Note: Conn_Close() removes the CLIENT structure as well. */
+	conn = Client_Conn(c);
+	if(conn > NONE)
+		Conn_Close(conn, NULL, Reason, true);
+	else
+		Client_Destroy(c, NULL, Reason, false);
+
+	/* Are we still connected or were we killed, too? */
+	if (my_conn > NONE && Conn_GetClient(my_conn))
+		return CONNECTED;
+	else
+		return DISCONNECTED;
+}
+
 /**
  * Send help for a given topic to the client.
  *

src/ngircd/irc.h

@@ -1,6 +1,6 @@
 /*
  * ngIRCd -- The Next Generation IRC Daemon
- * Copyright (c)2001-2012 Alexander Barton (alex@barton.de) and Contributors.
+ * Copyright (c)2001-2013 Alexander Barton (alex@barton.de) and Contributors.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -28,6 +28,9 @@ GLOBAL bool IRC_SQUERY PARAMS((CLIENT *Client, REQUEST *Req));
 GLOBAL bool IRC_TRACE PARAMS((CLIENT *Client, REQUEST *Req));
 GLOBAL bool IRC_HELP PARAMS((CLIENT *Client, REQUEST *Req));
 
+GLOBAL bool IRC_KillClient PARAMS((CLIENT *Client, CLIENT *From,
+				   const char *Nick, const char *Reason));
+
 #endif
 
 /* -eof- */