X-Git-Url: https://arthur.barton.de/cgi-bin/gitweb.cgi?p=ngircd-alex.git;a=blobdiff_plain;f=src%2Fngircd%2Firc-mode.c;h=71c9f796e952d592b28603c354012826b9dceeff;hp=aa979ac32dd287d436deaf7ff61687542ccc4360;hb=33a165721b79bf896a1895e79fa0809fd6f71174;hpb=1c7b9dbe931ecbb0f355ab66c9b422f7e6001058

diff --git a/src/ngircd/irc-mode.c b/src/ngircd/irc-mode.c
index aa979ac3..71c9f796 100644
--- a/src/ngircd/irc-mode.c
+++ b/src/ngircd/irc-mode.c
@@ -1,19 +1,21 @@
 /*
  * ngIRCd -- The Next Generation IRC Daemon
- * Copyright (c)2001-2008 Alexander Barton (alex@barton.de)
+ * Copyright (c)2001-2012 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
  * the Free Software Foundation; either version 2 of the License, or
  * (at your option) any later version.
  * Please read the file COPYING, README and AUTHORS for more information.
- *
- * IRC commands for mode changes (MODE, AWAY, ...)
  */
 
-
 #include "portab.h"
 
+/**
+ * @file
+ * IRC commands for mode changes (like MODE, AWAY, etc.)
+ */
+
 #include "imp.h"
 #include <assert.h>
 #include <stdio.h>
@@ -22,48 +24,66 @@
 
 #include "defines.h"
 #include "conn.h"
-#include "client.h"
 #include "channel.h"
 #include "irc-write.h"
 #include "lists.h"
 #include "log.h"
 #include "parse.h"
 #include "messages.h"
-#include "resolve.h"
 #include "conf.h"
 
 #include "exp.h"
 #include "irc-mode.h"
 
 
-static bool Client_Mode PARAMS(( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CLIENT *Target ));
-static bool Channel_Mode PARAMS(( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CHANNEL *Channel ));
+static bool Client_Mode PARAMS((CLIENT *Client, REQUEST *Req, CLIENT *Origin,
+				CLIENT *Target));
+static bool Channel_Mode PARAMS((CLIENT *Client, REQUEST *Req, CLIENT *Origin,
+				 CHANNEL *Channel));
 
-static bool Add_Ban_Invite PARAMS((int what, CLIENT *Prefix, CLIENT *Client, CHANNEL *Channel, const char *Pattern));
-static bool Del_Ban_Invite PARAMS((int what, CLIENT *Prefix, CLIENT *Client, CHANNEL *Channel, const char *Pattern));
+static bool Add_To_List PARAMS((char what, CLIENT *Prefix, CLIENT *Client,
+				CHANNEL *Channel, const char *Pattern));
+static bool Del_From_List PARAMS((char what, CLIENT *Prefix, CLIENT *Client,
+				  CHANNEL *Channel, const char *Pattern));
 
-static bool Send_ListChange PARAMS(( char *Mode, CLIENT *Prefix, CLIENT *Client, CHANNEL *Channel, const char *Mask ));
+static bool Send_ListChange PARAMS((const bool IsAdd, const char ModeChar,
+				    CLIENT *Prefix, CLIENT *Client,
+				    CHANNEL *Channel, const char *Mask));
 
 
+/**
+ * Handler for the IRC "MODE" command.
+ *
+ * See RFC 2812 section 3.1.5 ("user mode message") and section 3.2.3
+ * ("channel mode message"), and RFC 2811 section 4 ("channel modes").
+ *
+ * @param Client	The client from which this command has been received.
+ * @param Req		Request structure with prefix and all parameters.
+ * @returns		CONNECTED or DISCONNECTED.
+ */
 GLOBAL bool
 IRC_MODE( CLIENT *Client, REQUEST *Req )
 {
 	CLIENT *cl, *origin;
 	CHANNEL *chan;
 
-	assert( Client != NULL );
-	assert( Req != NULL );
+	assert(Client != NULL);
+	assert(Req != NULL);
 
 	/* No parameters? */
-	if( Req->argc < 1 ) return IRC_WriteStrClient( Client, ERR_NEEDMOREPARAMS_MSG, Client_ID( Client ), Req->command );
+	if (Req->argc < 1)
+		return IRC_WriteStrClient(Client, ERR_NEEDMOREPARAMS_MSG,
+					  Client_ID(Client), Req->command);
 
 	/* Origin for answers */
-	if( Client_Type( Client ) == CLIENT_SERVER )
-	{
-		origin = Client_Search( Req->prefix );
-		if( ! origin ) return IRC_WriteStrClient( Client, ERR_NOSUCHNICK_MSG, Client_ID( Client ), Req->prefix );
-	}
-	else origin = Client;
+	if (Client_Type(Client) == CLIENT_SERVER) {
+		origin = Client_Search(Req->prefix);
+		if (!origin)
+			return IRC_WriteStrClient(Client, ERR_NOSUCHNICK_MSG,
+						  Client_ID(Client),
+						  Req->prefix);
+	} else
+		origin = Client;
 
 	/* Channel or user mode? */
 	cl = NULL; chan = NULL;
@@ -83,158 +103,242 @@ IRC_MODE( CLIENT *Client, REQUEST *Req )
 } /* IRC_MODE */
 
 
+/**
+ * Check if the "mode limit" for a client has been reached.
+ *
+ * This limit doesn't apply for servers or services!
+ *
+ * @param Client The client to check.
+ * @param Count The number of modes already handled.
+ * @return true if the limit has been reached.
+ */
 static bool
-Client_Mode( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CLIENT *Target )
+Mode_Limit_Reached(CLIENT *Client, int Count)
 {
-	/* Handle client mode requests */
+	if (Client_Type(Client) == CLIENT_SERVER
+	    || Client_Type(Client) == CLIENT_SERVICE)
+		return false;
+	if (Count < MAX_HNDL_MODES_ARG)
+		return false;
+	return true;
+}
+
 
+/**
+ * Handle client mode requests
+ *
+ * @param Client	The client from which this command has been received.
+ * @param Req		Request structure with prefix and all parameters.
+ * @param Origin	The originator of the MODE command (prefix).
+ * @param Target	The target (client) of this MODE command.
+ * @returns		CONNECTED or DISCONNECTED.
+ */
+static bool
+Client_Mode( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CLIENT *Target )
+{
 	char the_modes[COMMAND_LEN], x[2], *mode_ptr;
 	bool ok, set;
 	int mode_arg;
 	size_t len;
 
 	/* Is the client allowed to request or change the modes? */
-	if( Client_Type( Client ) == CLIENT_USER )
-	{
+	if (Client_Type(Client) == CLIENT_USER) {
 		/* Users are only allowed to manipulate their own modes! */
-		if( Target != Client ) return IRC_WriteStrClient( Client, ERR_USERSDONTMATCH_MSG, Client_ID( Client ));
+		if (Target != Client)
+			return IRC_WriteStrClient(Client,
+						  ERR_USERSDONTMATCH_MSG,
+						  Client_ID(Client));
 	}
 
 	/* Mode request: let's answer it :-) */
-	if( Req->argc == 1 ) return IRC_WriteStrClient( Origin, RPL_UMODEIS_MSG, Client_ID( Origin ), Client_Modes( Target ));
+	if (Req->argc == 1)
+		return IRC_WriteStrClient(Origin, RPL_UMODEIS_MSG,
+					  Client_ID(Origin),
+					  Client_Modes(Target));
 
 	mode_arg = 1;
 	mode_ptr = Req->argv[mode_arg];
 
 	/* Initial state: set or unset modes? */
-	if( *mode_ptr == '+' ) set = true;
-	else if( *mode_ptr == '-' ) set = false;
-	else return IRC_WriteStrClient( Origin, ERR_UMODEUNKNOWNFLAG_MSG, Client_ID( Origin ));
-
-	/* Prepare reply string */
-	if( set ) strcpy( the_modes, "+" );
-	else strcpy( the_modes, "-" );
+	if (*mode_ptr == '+') {
+		set = true;
+		strcpy(the_modes, "+");
+	} else if (*mode_ptr == '-') {
+		set = false;
+		strcpy(the_modes, "-");
+	} else
+		return IRC_WriteStrClient(Origin, ERR_UMODEUNKNOWNFLAG_MSG,
+					  Client_ID(Origin));
 
 	x[1] = '\0';
 	ok = CONNECTED;
-	while( mode_ptr )
-	{
+	while (mode_ptr) {
 		mode_ptr++;
-		if( ! *mode_ptr )
-		{
+		if (!*mode_ptr) {
 			/* Try next argument if there's any */
 			mode_arg++;
-			if( mode_arg < Req->argc ) mode_ptr = Req->argv[mode_arg];
-			else break;
+			if (mode_arg < Req->argc)
+				mode_ptr = Req->argv[mode_arg];
+			else
+				break;
 		}
-		
-		switch( *mode_ptr )
-		{
-			case '+':
-			case '-':
-				if((( *mode_ptr == '+' ) && ( ! set )) || (( *mode_ptr == '-' ) && ( set )))
-				{
-					/* Action modifier ("+"/"-") must be changed ... */
-					len = strlen( the_modes ) - 1;
-					if(( the_modes[len] == '+' ) || ( the_modes[len] == '-' ))
-					{
-						/* Adjust last action modifier in result */
-						the_modes[len] = *mode_ptr;
-					}
-					else
-					{
-						/* Append modifier character to result string */
-						x[0] = *mode_ptr;
-						strlcat( the_modes, x, sizeof( the_modes ));
-					}
-					if( *mode_ptr == '+' ) set = true;
-					else set = false;
+
+		switch(*mode_ptr) {
+		  case '+':
+		  case '-':
+			if ((*mode_ptr == '+' && !set)
+			    || (*mode_ptr == '-' && set)) {
+				/* Action modifier ("+"/"-") must be changed */
+				len = strlen(the_modes) - 1;
+				if (the_modes[len] == '+'
+				    || the_modes[len] == '-') {
+					/* Last character in the "result
+					 * string" was an "action", so just
+					 * overwrite it with the new action */
+					the_modes[len] = *mode_ptr;
+				} else {
+					/* Append new modifier character to
+					 * the resulting mode string */
+					x[0] = *mode_ptr;
+					strlcat(the_modes, x,
+						sizeof(the_modes));
 				}
-				continue;
+				if (*mode_ptr == '+')
+					set = true;
+				else
+					set = false;
+			}
+			continue;
 		}
-		
+
 		/* Validate modes */
 		x[0] = '\0';
-		switch( *mode_ptr )
-		{
-			case 'i': /* Invisible */
-			case 's': /* Server messages */
-			case 'w': /* Wallops messages */
-				x[0] = *mode_ptr;
-				break;
-
-			case 'a': /* Away */
-				if( Client_Type( Client ) == CLIENT_SERVER )
-				{
-					x[0] = 'a';
-					Client_SetAway( Origin, DEFAULT_AWAY_MSG );
-				}
-				else ok = IRC_WriteStrClient( Origin, ERR_NOPRIVILEGES_MSG, Client_ID( Origin ));
-				break;
-
-			case 'o': /* IRC operator (only unsettable!) */
-				if(( ! set ) || ( Client_Type( Client ) == CLIENT_SERVER ))
-				{
-					Client_SetOperByMe( Target, false );
-					x[0] = 'o';
-				}
-				else ok = IRC_WriteStrClient( Origin, ERR_NOPRIVILEGES_MSG, Client_ID( Origin ));
-				break;
-
-			case 'r': /* Restricted (only settable) */
-				if(( set ) || ( Client_Type( Client ) == CLIENT_SERVER )) x[0] = 'r';
-				else ok = IRC_WriteStrClient( Origin, ERR_RESTRICTED_MSG, Client_ID( Origin ));
-				break;
-
-			default:
-				Log( LOG_DEBUG, "Unknown mode \"%c%c\" from \"%s\"!?", set ? '+' : '-', *mode_ptr, Client_ID( Origin ));
-				if( Client_Type( Client ) != CLIENT_SERVER ) ok = IRC_WriteStrClient( Origin, ERR_UMODEUNKNOWNFLAG2_MSG, Client_ID( Origin ), set ? '+' : '-', *mode_ptr );
+		switch (*mode_ptr) {
+		case 'C': /* Only messages from clients sharing a channel */
+		case 'i': /* Invisible */
+		case 's': /* Server messages */
+		case 'w': /* Wallops messages */
+			x[0] = *mode_ptr;
+			break;
+		case 'a': /* Away */
+			if (Client_Type(Client) == CLIENT_SERVER) {
+				x[0] = 'a';
+				Client_SetAway(Origin, DEFAULT_AWAY_MSG);
+			} else
+				ok = IRC_WriteStrClient(Origin,
+							ERR_NOPRIVILEGES_MSG,
+							Client_ID(Origin));
+			break;
+		case 'c': /* Receive connect notices
+			   * (only settable by IRC operators!) */
+			if (!set || Client_Type(Client) == CLIENT_SERVER
+			    || Client_OperByMe(Origin))
+				x[0] = 'c';
+			else
+				ok = IRC_WriteStrClient(Origin,
+							ERR_NOPRIVILEGES_MSG,
+							Client_ID(Origin));
+			break;
+		case 'o': /* IRC operator (only unsettable!) */
+			if (!set || Client_Type(Client) == CLIENT_SERVER) {
+				Client_SetOperByMe(Target, false);
+				x[0] = 'o';
+			} else
+				ok = IRC_WriteStrClient(Origin,
+							ERR_NOPRIVILEGES_MSG,
+							Client_ID(Origin));
+			break;
+		case 'r': /* Restricted (only settable) */
+			if (set || Client_Type(Client) == CLIENT_SERVER)
+				x[0] = 'r';
+			else
+				ok = IRC_WriteStrClient(Origin,
+							ERR_RESTRICTED_MSG,
+							Client_ID(Origin));
+			break;
+		case 'x': /* Cloak hostname */
+			if (Client_HasMode(Client, 'r'))
+				ok = IRC_WriteStrClient(Origin,
+							ERR_RESTRICTED_MSG,
+							Client_ID(Origin));
+			else
+				x[0] = 'x';
+			break;
+		default:
+			if (Client_Type(Client) != CLIENT_SERVER) {
+				Log(LOG_DEBUG,
+				    "Unknown mode \"%c%c\" from \"%s\"!?",
+				    set ? '+' : '-', *mode_ptr,
+				    Client_ID(Origin));
+				ok = IRC_WriteStrClient(Origin,
+							ERR_UMODEUNKNOWNFLAG2_MSG,
+							Client_ID(Origin),
+							set ? '+' : '-',
+							*mode_ptr);
 				x[0] = '\0';
-				goto client_exit;
+			} else {
+				Log(LOG_DEBUG,
+				    "Handling unknown mode \"%c%c\" from \"%s\" for \"%s\" ...",
+				    set ? '+' : '-', *mode_ptr,
+				    Client_ID(Origin), Client_ID(Target));
+				x[0] = *mode_ptr;
+			}
 		}
-		if( ! ok ) break;
 
-		/* Is there a valid mode change? */
-		if( ! x[0] ) continue;
+		if (!ok)
+			break;
 
-		if( set )
-		{
-			/* Set mode */
-			if( Client_ModeAdd( Target, x[0] )) strlcat( the_modes, x, sizeof( the_modes ));
+		/* Is there a valid mode change? */
+		if (!x[0])
+			continue;
 
+		if (set) {
+			if (Client_ModeAdd(Target, x[0]))
+				strlcat(the_modes, x, sizeof(the_modes));
+		} else {
+			if (Client_ModeDel(Target, x[0]))
+				strlcat(the_modes, x, sizeof(the_modes));
 		}
-		else
-		{
-			/* Unset mode */
-			if( Client_ModeDel( Target, x[0] )) strlcat( the_modes, x, sizeof( the_modes ));
-		}		
 	}
-client_exit:
-	
+
 	/* Are there changed modes? */
-	if( the_modes[1] )
-	{
-		/* Remoce needless action modifier characters */
-		len = strlen( the_modes ) - 1;
-		if(( the_modes[len] == '+' ) || ( the_modes[len] == '-' )) the_modes[len] = '\0';
+	if (the_modes[1]) {
+		/* Remove needless action modifier characters */
+		len = strlen(the_modes) - 1;
+		if (the_modes[len] == '+' || the_modes[len] == '-')
+			the_modes[len] = '\0';
 
-		if( Client_Type( Client ) == CLIENT_SERVER )
-		{
+		if (Client_Type(Client) == CLIENT_SERVER) {
 			/* Forward modes to other servers */
-			IRC_WriteStrServersPrefix( Client, Origin, "MODE %s :%s", Client_ID( Target ), the_modes );
-		}
-		else
-		{
+			if (Client_Conn(Target) != NONE) {
+				/* Remote server (service?) changed modes
+				 * for one of our clients. Inform it! */
+				IRC_WriteStrClientPrefix(Target, Origin,
+							 "MODE %s :%s",
+							 Client_ID(Target),
+							 the_modes);
+			}
+			IRC_WriteStrServersPrefix(Client, Origin,
+						  "MODE %s :%s",
+						  Client_ID(Target),
+						  the_modes);
+		} else {
 			/* Send reply to client and inform other servers */
-			ok = IRC_WriteStrClientPrefix( Client, Origin, "MODE %s :%s", Client_ID( Target ), the_modes );
-			IRC_WriteStrServersPrefix( Client, Origin, "MODE %s :%s", Client_ID( Target ), the_modes );
+			ok = IRC_WriteStrClientPrefix(Client, Origin,
+						      "MODE %s :%s",
+						      Client_ID(Target),
+						      the_modes);
+			IRC_WriteStrServersPrefix(Client, Origin,
+						  "MODE %s :%s",
+						  Client_ID(Target),
+						  the_modes);
 		}
 		LogDebug("%s \"%s\": Mode change, now \"%s\".",
 			 Client_TypeText(Target), Client_Mask(Target),
 			 Client_Modes(Target));
 	}
-	
-	IRC_SetPenalty( Client, 1 );	
+
+	IRC_SetPenalty(Client, 1);
 	return ok;
 } /* Client_Mode */
 
@@ -271,25 +375,35 @@ Channel_Mode_Answer_Request(CLIENT *Origin, CHANNEL *Channel)
 	if (the_args[0])
 		strlcat(the_modes, the_args, sizeof(the_modes));
 
-	return IRC_WriteStrClient(Origin, RPL_CHANNELMODEIS_MSG,
-		Client_ID(Origin), Channel_Name(Channel), the_modes);
+	if (!IRC_WriteStrClient(Origin, RPL_CHANNELMODEIS_MSG,
+				Client_ID(Origin), Channel_Name(Channel),
+				the_modes))
+		return DISCONNECTED;
+#ifndef STRICT_RFC
+	if (!IRC_WriteStrClient(Origin, RPL_CREATIONTIME_MSG,
+				  Client_ID(Origin), Channel_Name(Channel),
+				  Channel_CreationTime(Channel)))
+		return DISCONNECTED;
+#endif
+	return CONNECTED;
 }
 
 
+/**
+ * Handle channel mode and channel-user mode changes
+ */
 static bool
-Channel_Mode( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CHANNEL *Channel )
+Channel_Mode(CLIENT *Client, REQUEST *Req, CLIENT *Origin, CHANNEL *Channel)
 {
-	/* Handle channel and channel-user modes */
-
-	char the_modes[COMMAND_LEN], the_args[COMMAND_LEN], x[2], argadd[CLIENT_PASS_LEN], *mode_ptr;
-	bool ok, set, modeok = true, skiponce, use_servermode = false, retval;
-	int mode_arg, arg_arg;
+	char the_modes[COMMAND_LEN], the_args[COMMAND_LEN], x[2],
+	    argadd[CLIENT_PASS_LEN], *mode_ptr;
+	bool connected, set, skiponce, retval, onchannel, modeok, use_servermode;
+	int mode_arg, arg_arg, mode_arg_count = 0;
 	CLIENT *client;
 	long l;
 	size_t len;
 
-	/* Are modes allowed on channel? */
-	if (Channel_Name(Channel)[0] == '+')
+	if (Channel_IsModeless(Channel))
 		return IRC_WriteStrClient(Client, ERR_NOCHANMODES_MSG,
 				Client_ID(Client), Channel_Name(Channel));
 
@@ -297,25 +411,13 @@ Channel_Mode( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CHANNEL *Channel )
 	if (Req->argc <= 1)
 		return Channel_Mode_Answer_Request(Origin, Channel);
 
-	/* Is the user allowed to change modes? */
-	if (Client_Type(Client) == CLIENT_USER) {
-		/* Is the originating user on that channel? */
-		if (!Channel_IsMemberOf(Channel, Origin))
-			return IRC_WriteStrClient(Origin, ERR_NOTONCHANNEL_MSG,
-				Client_ID(Origin), Channel_Name(Channel));
-		modeok = false;
-		/* channel operator? */
-		if (strchr(Channel_UserModes(Channel, Origin), 'o'))
-			modeok = true;
-		else if(Conf_OperCanMode) {
-			/* IRC-Operators can use MODE as well */
-			if (Client_OperByMe(Origin)) {
-				modeok = true;
-				if (Conf_OperServerMode)
-					use_servermode = true; /* Change Origin to Server */
-			}
-		}
-	}
+	Channel_CheckAdminRights(Channel, Client, Origin,
+				 &onchannel, &modeok, &use_servermode);
+
+	if (!onchannel && !modeok)
+		return IRC_WriteStrClient(Origin, ERR_NOTONCHANNEL_MSG,
+					  Client_ID(Origin),
+					  Channel_Name(Channel));
 
 	mode_arg = 1;
 	mode_ptr = Req->argv[mode_arg];
@@ -327,8 +429,12 @@ Channel_Mode( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CHANNEL *Channel )
 	/* Initial state: set or unset modes? */
 	skiponce = false;
 	switch (*mode_ptr) {
-	case '-': set = false; break;
-	case '+': set = true; break;
+	case '-':
+		set = false;
+		break;
+	case '+':
+		set = true;
+		break;
 	default:
 		set = true;
 		skiponce = true;
@@ -339,12 +445,14 @@ Channel_Mode( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CHANNEL *Channel )
 	the_args[0] = '\0';
 
 	x[1] = '\0';
-	ok = CONNECTED;
+	connected = CONNECTED;
 	while (mode_ptr) {
-		if (! skiponce)
+		if (!skiponce)
 			mode_ptr++;
 		if (!*mode_ptr) {
 			/* Try next argument if there's any */
+			if (arg_arg < 0)
+				break;
 			if (arg_arg > mode_arg)
 				mode_arg = arg_arg;
 			else
@@ -364,10 +472,11 @@ Channel_Mode( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CHANNEL *Channel )
 		switch (*mode_ptr) {
 		case '+':
 		case '-':
-			if (((*mode_ptr == '+') && !set) || ((*mode_ptr == '-') && set)) {
+			if (((*mode_ptr == '+') && !set)
+			    || ((*mode_ptr == '-') && set)) {
 				/* Action modifier ("+"/"-") must be changed ... */
-				len = strlen( the_modes ) - 1;
-				if ((the_modes[len] == '+') || (the_modes[len] == '-')) {
+				len = strlen(the_modes) - 1;
+				if (the_modes[len] == '+' || the_modes[len] == '-') {
 					/* Adjust last action modifier in result */
 					the_modes[len] = *mode_ptr;
 				} else {
@@ -381,7 +490,8 @@ Channel_Mode( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CHANNEL *Channel )
 		}
 
 		/* Are there arguments left? */
-		if( arg_arg >= Req->argc ) arg_arg = -1;
+		if (arg_arg >= Req->argc)
+			arg_arg = -1;
 
 		/* Validate modes */
 		x[0] = '\0';
@@ -392,42 +502,64 @@ Channel_Mode( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CHANNEL *Channel )
 		case 'i': /* Invite only */
 		case 'm': /* Moderated */
 		case 'n': /* Only members can write */
+		case 'R': /* Registered users only */
 		case 's': /* Secret channel */
 		case 't': /* Topic locked */
+		case 'z': /* Secure connections only */
 			if (modeok)
 				x[0] = *mode_ptr;
 			else
-				ok = IRC_WriteStrClient(Origin, ERR_CHANOPRIVSNEEDED_MSG, Client_ID(Origin), Channel_Name(Channel));
+				connected = IRC_WriteStrClient(Origin,
+					ERR_CHANOPRIVSNEEDED_MSG,
+					Client_ID(Origin), Channel_Name(Channel));
 			break;
 		case 'k': /* Channel key */
-			if (! set) {
+			if (Mode_Limit_Reached(Client, mode_arg_count++))
+				goto chan_exit;
+			if (!set) {
 				if (modeok)
 					x[0] = *mode_ptr;
 				else
-					ok = IRC_WriteStrClient(Origin, ERR_CHANOPRIVSNEEDED_MSG, Client_ID(Origin), Channel_Name(Channel));
+					connected = IRC_WriteStrClient(Origin,
+						ERR_CHANOPRIVSNEEDED_MSG,
+						Client_ID(Origin),
+						Channel_Name(Channel));
 				break;
 			}
 			if (arg_arg > mode_arg) {
 				if (modeok) {
 					Channel_ModeDel(Channel, 'k');
-					Channel_SetKey(Channel, Req->argv[arg_arg]);
-					strlcpy(argadd, Channel_Key(Channel), sizeof(argadd));
+					Channel_SetKey(Channel,
+						       Req->argv[arg_arg]);
+					strlcpy(argadd, Channel_Key(Channel),
+						sizeof(argadd));
 					x[0] = *mode_ptr;
 				} else {
-					ok = IRC_WriteStrClient(Origin, ERR_CHANOPRIVSNEEDED_MSG, Client_ID(Origin), Channel_Name(Channel));
+					connected = IRC_WriteStrClient(Origin,
+						ERR_CHANOPRIVSNEEDED_MSG,
+						Client_ID(Origin),
+						Channel_Name(Channel));
 				}
 				Req->argv[arg_arg][0] = '\0';
 				arg_arg++;
 			} else {
-				ok = IRC_WriteStrClient(Origin, ERR_NEEDMOREPARAMS_MSG, Client_ID(Origin), Req->command);
+				connected = IRC_WriteStrClient(Origin,
+					ERR_NEEDMOREPARAMS_MSG,
+					Client_ID(Origin), Req->command);
+				goto chan_exit;
 			}
 			break;
 		case 'l': /* Member limit */
+			if (Mode_Limit_Reached(Client, mode_arg_count++))
+				goto chan_exit;
 			if (!set) {
 				if (modeok)
 					x[0] = *mode_ptr;
 				else
-					ok = IRC_WriteStrClient(Origin, ERR_CHANOPRIVSNEEDED_MSG, Client_ID(Origin), Channel_Name(Channel));
+					connected = IRC_WriteStrClient(Origin,
+						ERR_CHANOPRIVSNEEDED_MSG,
+						Client_ID(Origin),
+						Channel_Name(Channel));
 				break;
 			}
 			if (arg_arg > mode_arg) {
@@ -436,30 +568,70 @@ Channel_Mode( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CHANNEL *Channel )
 					if (l > 0 && l < 0xFFFF) {
 						Channel_ModeDel(Channel, 'l');
 						Channel_SetMaxUsers(Channel, l);
-						snprintf(argadd, sizeof(argadd), "%ld", l);
+						snprintf(argadd, sizeof(argadd),
+							 "%ld", l);
 						x[0] = *mode_ptr;
 					}
 				} else {
-					ok = IRC_WriteStrClient(Origin, ERR_CHANOPRIVSNEEDED_MSG, Client_ID(Origin), Channel_Name(Channel));
+					connected = IRC_WriteStrClient(Origin,
+						ERR_CHANOPRIVSNEEDED_MSG,
+						Client_ID(Origin),
+						Channel_Name(Channel));
 				}
 				Req->argv[arg_arg][0] = '\0';
 				arg_arg++;
 			} else {
-				ok = IRC_WriteStrClient(Origin, ERR_NEEDMOREPARAMS_MSG, Client_ID(Origin), Req->command);
+				connected = IRC_WriteStrClient(Origin,
+					ERR_NEEDMOREPARAMS_MSG,
+					Client_ID(Origin), Req->command);
+				goto chan_exit;
 			}
 			break;
+		case 'O': /* IRC operators only */
+			if (modeok) {
+				/* Only IRC operators are allowed to
+				 * set the 'O' channel mode! */
+				if (set && !(Client_OperByMe(Client)
+				    || Client_Type(Client) == CLIENT_SERVER))
+					connected = IRC_WriteStrClient(Origin,
+						ERR_NOPRIVILEGES_MSG,
+						Client_ID(Origin));
+				else
+					x[0] = 'O';
+			} else
+				connected = IRC_WriteStrClient(Origin,
+						ERR_CHANOPRIVSNEEDED_MSG,
+						Client_ID(Origin),
+						Channel_Name(Channel));
+				break;
 		case 'P': /* Persistent channel */
 			if (modeok) {
 				/* Only IRC operators are allowed to
 				 * set the 'P' channel mode! */
-				if (set && !(Client_OperByMe(Client) || Client_Type(Client) == CLIENT_SERVER))
-					ok = IRC_WriteStrClient(Origin, ERR_NOPRIVILEGES_MSG, Client_ID(Origin));
+				if (set && !(Client_OperByMe(Client)
+				    || Client_Type(Client) == CLIENT_SERVER))
+					connected = IRC_WriteStrClient(Origin,
+						ERR_NOPRIVILEGES_MSG,
+						Client_ID(Origin));
 				else
-						x[0] = 'P';
+					x[0] = 'P';
 			} else
-				ok = IRC_WriteStrClient(Origin, ERR_CHANOPRIVSNEEDED_MSG, Client_ID(Origin), Channel_Name(Channel));
+				connected = IRC_WriteStrClient(Origin,
+					ERR_CHANOPRIVSNEEDED_MSG,
+					Client_ID(Origin),
+					Channel_Name(Channel));
 			break;
 		/* --- Channel user modes --- */
+		case 'a':
+		case 'h':
+		case 'q':
+			if (Client_Type(Client) != CLIENT_SERVER) {
+				connected = IRC_WriteStrClient(Origin,
+					ERR_CHANOPRIVSNEEDED_MSG,
+					Client_ID(Origin),
+					Channel_Name(Channel));
+				goto chan_exit;
+			}
 		case 'o': /* Channel operator */
 		case 'v': /* Voice */
 			if (arg_arg > mode_arg) {
@@ -468,27 +640,45 @@ Channel_Mode( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CHANNEL *Channel )
 					if (client)
 						x[0] = *mode_ptr;
 					else
-						ok = IRC_WriteStrClient(Client, ERR_NOSUCHNICK_MSG, Client_ID(Client), Req->argv[arg_arg]);
+						connected = IRC_WriteStrClient(Client,
+							ERR_NOSUCHNICK_MSG,
+							Client_ID(Client),
+							Req->argv[arg_arg]);
 				} else {
-					ok = IRC_WriteStrClient(Origin, ERR_CHANOPRIVSNEEDED_MSG, Client_ID(Origin), Channel_Name(Channel));
+					connected = IRC_WriteStrClient(Origin,
+						ERR_CHANOPRIVSNEEDED_MSG,
+						Client_ID(Origin),
+						Channel_Name(Channel));
 				}
 				Req->argv[arg_arg][0] = '\0';
 				arg_arg++;
 			} else {
-				ok = IRC_WriteStrClient(Origin, ERR_NEEDMOREPARAMS_MSG, Client_ID(Origin), Req->command);
+				connected = IRC_WriteStrClient(Origin,
+					ERR_NEEDMOREPARAMS_MSG,
+					Client_ID(Origin), Req->command);
+				goto chan_exit;
 			}
 			break;
 		/* --- Channel lists --- */
 		case 'I': /* Invite lists */
 		case 'b': /* Ban lists */
+			if (Mode_Limit_Reached(Client, mode_arg_count++))
+				goto chan_exit;
 			if (arg_arg > mode_arg) {
 				/* modify list */
 				if (modeok) {
-					ok = set ? Add_Ban_Invite(*mode_ptr, Origin, Client, Channel, Req->argv[arg_arg])
-						 : Del_Ban_Invite(*mode_ptr, Origin, Client, Channel, Req->argv[arg_arg]);
+					connected = set
+					   ? Add_To_List(*mode_ptr, Origin,
+						Client, Channel,
+						Req->argv[arg_arg])
+					   : Del_From_List(*mode_ptr, Origin,
+						Client, Channel,
+						Req->argv[arg_arg]);
 				} else {
-					ok = IRC_WriteStrClient(Origin, ERR_CHANOPRIVSNEEDED_MSG,
-							Client_ID(Origin), Channel_Name(Channel));
+					connected = IRC_WriteStrClient(Origin,
+						ERR_CHANOPRIVSNEEDED_MSG,
+						Client_ID(Origin),
+						Channel_Name(Channel));
 				}
 				Req->argv[arg_arg][0] = '\0';
 				arg_arg++;
@@ -500,15 +690,26 @@ Channel_Mode( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CHANNEL *Channel )
 			}
 			break;
 		default:
-			Log(LOG_DEBUG, "Unknown mode \"%c%c\" from \"%s\" on %s!?",
-				set ? '+' : '-', *mode_ptr, Client_ID(Origin), Channel_Name(Channel));
-			if (Client_Type(Client) != CLIENT_SERVER)
-				ok = IRC_WriteStrClient(Origin, ERR_UMODEUNKNOWNFLAG2_MSG, Client_ID(Origin), set ? '+' : '-', *mode_ptr);
-			x[0] = '\0';
-			goto chan_exit;
-		} /* switch() */
+			if (Client_Type(Client) != CLIENT_SERVER) {
+				Log(LOG_DEBUG,
+				    "Unknown mode \"%c%c\" from \"%s\" on %s!?",
+				    set ? '+' : '-', *mode_ptr,
+				    Client_ID(Origin), Channel_Name(Channel));
+				connected = IRC_WriteStrClient(Origin,
+					ERR_UNKNOWNMODE_MSG,
+					Client_ID(Origin), *mode_ptr,
+					Channel_Name(Channel));
+				x[0] = '\0';
+			} else {
+				Log(LOG_DEBUG,
+				    "Handling unknown mode \"%c%c\" from \"%s\" on %s ...",
+				    set ? '+' : '-', *mode_ptr,
+				    Client_ID(Origin), Channel_Name(Channel));
+				x[0] = *mode_ptr;
+			}
+		}
 
-		if (!ok)
+		if (!connected)
 			break;
 
 		/* Is there a valid mode change? */
@@ -517,29 +718,40 @@ Channel_Mode( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CHANNEL *Channel )
 
 		/* Validate target client */
 		if (client && (!Channel_IsMemberOf(Channel, client))) {
-			if (!IRC_WriteStrClient(Origin, ERR_USERNOTINCHANNEL_MSG,
-				Client_ID(Origin), Client_ID(client), Channel_Name(Channel)))
-					break;
+			if (!IRC_WriteStrClient
+			    (Origin, ERR_USERNOTINCHANNEL_MSG,
+			     Client_ID(Origin), Client_ID(client),
+			     Channel_Name(Channel)))
+				break;
 
 			continue;
 		}
 
 		if (client) {
 			/* Channel-User-Mode */
-			retval = set ? Channel_UserModeAdd(Channel, client, x[0]) : Channel_UserModeDel(Channel, client, x[0]);
+			retval = set
+			       ? Channel_UserModeAdd(Channel, client, x[0])
+			       : Channel_UserModeDel(Channel, client, x[0]);
 			if (retval) {
 				strlcat(the_args, " ", sizeof(the_args));
-				strlcat(the_args, Client_ID(client), sizeof(the_args));
+				strlcat(the_args, Client_ID(client),
+					sizeof(the_args));
 				strlcat(the_modes, x, sizeof(the_modes));
-				LogDebug("User \"%s\": Mode change on %s, now \"%s\"",
-					Client_Mask(client), Channel_Name(Channel), Channel_UserModes(Channel, client));
+				LogDebug
+				    ("User \"%s\": Mode change on %s, now \"%s\"",
+				     Client_Mask(client), Channel_Name(Channel),
+				     Channel_UserModes(Channel, client));
 			}
 		} else {
 			/* Channel-Mode */
-			retval = set ? Channel_ModeAdd(Channel, x[0]) : Channel_ModeDel(Channel, x[0]);
+			retval = set
+			       ? Channel_ModeAdd(Channel, x[0])
+			       : Channel_ModeDel(Channel, x[0]);
 			if (retval) {
 				strlcat(the_modes, x, sizeof(the_modes));
-				LogDebug("Channel %s: Mode change, now \"%s\".", Channel_Name(Channel), Channel_Modes(Channel));
+				LogDebug("Channel %s: Mode change, now \"%s\".",
+					 Channel_Name(Channel),
+					 Channel_Modes(Channel));
 			}
 		}
 
@@ -549,7 +761,8 @@ Channel_Mode( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CHANNEL *Channel )
 			strlcat(the_args, argadd, sizeof(the_args));
 		}
 	}
-chan_exit:
+
+      chan_exit:
 	/* Are there changed modes? */
 	if (the_modes[1]) {
 		/* Clean up mode string */
@@ -567,14 +780,19 @@ chan_exit:
 
 			/* Forward mode changes to channel users and all the
 			 * other remote servers: */
-			IRC_WriteStrServersPrefix(Client, Origin, "MODE %s %s%s", Channel_Name( Channel ), the_modes, the_args);
-			IRC_WriteStrChannelPrefix(Client, Channel, Origin, false, "MODE %s %s%s", Channel_Name(Channel), the_modes, the_args);
+			IRC_WriteStrServersPrefix(Client, Origin,
+				"MODE %s %s%s", Channel_Name(Channel),
+				the_modes, the_args);
+			IRC_WriteStrChannelPrefix(Client, Channel, Origin,
+				false, "MODE %s %s%s", Channel_Name(Channel),
+				the_modes, the_args);
 		} else {
 			if (use_servermode)
 				Origin = Client_ThisServer();
 			/* Send reply to client and inform other servers and channel users */
-			ok = IRC_WriteStrClientPrefix(Client, Origin, "MODE %s %s%s",
-					Channel_Name(Channel), the_modes, the_args);
+			connected = IRC_WriteStrClientPrefix(Client, Origin,
+					"MODE %s %s%s", Channel_Name(Channel),
+					the_modes, the_args);
 			/* Only forward requests for non-local channels */
 			if (!Channel_IsLocal(Channel))
 				IRC_WriteStrServersPrefix(Client, Origin,
@@ -587,7 +805,7 @@ chan_exit:
 	}
 
 	IRC_SetPenalty(Client, 1);
-	return CONNECTED;
+	return connected;
 } /* Channel_Mode */
 
 
@@ -597,12 +815,10 @@ IRC_AWAY( CLIENT *Client, REQUEST *Req )
 	assert( Client != NULL );
 	assert( Req != NULL );
 
-	/* Falsche Anzahl Parameter? */
 	if( Req->argc > 1 ) return IRC_WriteStrClient( Client, ERR_NEEDMOREPARAMS_MSG, Client_ID( Client ), Req->command );
 
 	if(( Req->argc == 1 ) && (Req->argv[0][0] ))
 	{
-		/* AWAY setzen */
 		Client_SetAway( Client, Req->argv[0] );
 		Client_ModeAdd( Client, 'a' );
 		IRC_WriteStrServersPrefix( Client, Client, "MODE %s :+a", Client_ID( Client ));
@@ -610,7 +826,6 @@ IRC_AWAY( CLIENT *Client, REQUEST *Req )
 	}
 	else
 	{
-		/* AWAY loeschen */
 		Client_ModeDel( Client, 'a' );
 		IRC_WriteStrServersPrefix( Client, Client, "MODE %s :-a", Client_ID( Client ));
 		return IRC_WriteStrClient( Client, RPL_UNAWAY_MSG, Client_ID( Client ));
@@ -618,83 +833,137 @@ IRC_AWAY( CLIENT *Client, REQUEST *Req )
 } /* IRC_AWAY */
 
 
+/**
+ * Add entries to channel invite, ban and exception lists.
+ *
+ * @param what Can be 'I' for invite or 'b' for ban list.
+ * @param Prefix The originator of the command.
+ * @param Client The sender of the command.
+ * @param Channel The channel of which the list should be modified.
+ * @param Pattern The pattern to add to the list.
+ * @return CONNECTED or DISCONNECTED.
+ */
 static bool
-Add_Ban_Invite(int what, CLIENT *Prefix, CLIENT *Client, CHANNEL *Channel, const char *Pattern)
+Add_To_List(char what, CLIENT *Prefix, CLIENT *Client, CHANNEL *Channel,
+	    const char *Pattern)
 {
 	const char *mask;
-	bool already;
-	bool ret;
+	struct list_head *list;
 
-	assert( Client != NULL );
-	assert( Channel != NULL );
-	assert( Pattern != NULL );
+	assert(Client != NULL);
+	assert(Channel != NULL);
+	assert(Pattern != NULL);
 	assert(what == 'I' || what == 'b');
 
 	mask = Lists_MakeMask(Pattern);
 
-	already = Lists_CheckDupeMask(Channel_GetListInvites(Channel), mask);
-	if (!already) {
-		if (what == 'I')
-			ret = Channel_AddInvite(Channel, mask, false);
-		else
-			ret = Channel_AddBan(Channel, mask);
-		if (!ret)
-			return CONNECTED;
+	switch(what) {
+		case 'I':
+			list = Channel_GetListInvites(Channel);
+			break;
+		case 'b':
+			list = Channel_GetListBans(Channel);
+			break;
 	}
-	if (already && (Client_Type(Prefix) == CLIENT_SERVER))
-		return CONNECTED;
 
-	if (what == 'I')
-		return Send_ListChange("+I", Prefix, Client, Channel, mask);
-	return Send_ListChange("+b", Prefix, Client, Channel, mask);
+	if (Lists_CheckDupeMask(list, mask))
+		return CONNECTED;
+	if (Client_Type(Client) == CLIENT_USER &&
+	    Lists_Count(list) >= MAX_HNDL_CHANNEL_LISTS)
+		return IRC_WriteStrClient(Client, ERR_LISTFULL_MSG,
+					  Client_ID(Client),
+					  Channel_Name(Channel), mask,
+					  MAX_HNDL_CHANNEL_LISTS);
+
+	switch (what) {
+		case 'I':
+			if (!Channel_AddInvite(Channel, mask, false))
+				return CONNECTED;
+			break;
+		case 'b':
+			if (!Channel_AddBan(Channel, mask))
+				return CONNECTED;
+			break;
+	}
+	return Send_ListChange(true, what, Prefix, Client, Channel, mask);
 }
 
 
+/**
+ * Delete entries from channel invite, ban and exeption lists.
+ *
+ * @param what Can be 'I' for invite or 'b' for ban list.
+ * @param Prefix The originator of the command.
+ * @param Client The sender of the command.
+ * @param Channel The channel of which the list should be modified.
+ * @param Pattern The pattern to add to the list.
+ * @return CONNECTED or DISCONNECTED.
+ */
 static bool
-Del_Ban_Invite(int what, CLIENT *Prefix, CLIENT *Client, CHANNEL *Channel, const char *Pattern)
+Del_From_List(char what, CLIENT *Prefix, CLIENT *Client, CHANNEL *Channel,
+	      const char *Pattern)
 {
 	const char *mask;
 	struct list_head *list;
 
-	assert( Client != NULL );
-	assert( Channel != NULL );
-	assert( Pattern != NULL );
+	assert(Client != NULL);
+	assert(Channel != NULL);
+	assert(Pattern != NULL);
 	assert(what == 'I' || what == 'b');
 
-	mask = Lists_MakeMask( Pattern );
+	mask = Lists_MakeMask(Pattern);
 
-	if (what == 'I')
-		list = Channel_GetListInvites(Channel);
-	else
-		list = Channel_GetListBans(Channel);
+	switch (what) {
+		case 'I':
+			list = Channel_GetListInvites(Channel);
+			break;
+		case 'b':
+			list = Channel_GetListBans(Channel);
+			break;
+	}
 
+	if (!Lists_CheckDupeMask(list, mask))
+		return CONNECTED;
 	Lists_Del(list, mask);
-	if (what == 'I')
-		return Send_ListChange( "-I", Prefix, Client, Channel, mask );
-	return Send_ListChange( "-b", Prefix, Client, Channel, mask );
+
+	return Send_ListChange(false, what, Prefix, Client, Channel, mask);
 }
 
 
+/**
+ * Send information about changed channel ban/invite lists to clients.
+ *
+ * @param IsAdd true if the list item has been added, false otherwise.
+ * @param ModeChar The mode to use (e. g. 'b' or 'I')
+ * @param Prefix The originator of the mode list change.
+ * @param Client The sender of the command.
+ * @param Channel The channel of which the list has been modified.
+ * @param Mask The mask which has been added or removed.
+ * @return CONNECTED or DISCONNECTED.
+ */
 static bool
-Send_ListChange( char *Mode, CLIENT *Prefix, CLIENT *Client, CHANNEL *Channel, const char *Mask )
+Send_ListChange(const bool IsAdd, const char ModeChar, CLIENT *Prefix,
+		CLIENT *Client, CHANNEL *Channel, const char *Mask)
 {
-	/* Bestaetigung an Client schicken & andere Server sowie Channel-User informieren */
+	bool ok = true;
 
-	bool ok;
+	/* Send confirmation to the client */
+	if (Client_Type(Client) == CLIENT_USER)
+		ok = IRC_WriteStrClientPrefix(Client, Prefix, "MODE %s %c%c %s",
+					      Channel_Name(Channel),
+					      IsAdd ? '+' : '-',
+					      ModeChar, Mask);
 
-	if( Client_Type( Client ) == CLIENT_USER )
-	{
-		/* Bestaetigung an Client */
-		ok = IRC_WriteStrClientPrefix( Client, Prefix, "MODE %s %s %s", Channel_Name( Channel ), Mode, Mask );
-	}
-	else ok = true;
+	/* to other servers */
+	IRC_WriteStrServersPrefix(Client, Prefix, "MODE %s %c%c %s",
+				  Channel_Name(Channel), IsAdd ? '+' : '-',
+				  ModeChar, Mask);
 
-	/* an andere Server */
-	IRC_WriteStrServersPrefix( Client, Prefix, "MODE %s %s %s", Channel_Name( Channel ), Mode, Mask );
+	/* and local users in channel */
+	IRC_WriteStrChannelPrefix(Client, Channel, Prefix, false,
+				  "MODE %s %c%c %s", Channel_Name(Channel),
+				  IsAdd ? '+' : '-', ModeChar, Mask );
 
-	/* und lokale User im Channel */
-	IRC_WriteStrChannelPrefix( Client, Channel, Prefix, false, "MODE %s %s %s", Channel_Name( Channel ), Mode, Mask );
-	
 	return ok;
 } /* Send_ListChange */