]> arthur.barton.de Git - ngircd-alex.git/blobdiff - src/ngircd/irc-mode.c
Reduce the number of calls of strlen(). Idea by Florin Westphal.
[ngircd-alex.git] / src / ngircd / irc-mode.c
index 148698ac48096ab562fb28f393e9eaea968e53d6..2f657f271fdcd911971e8023c1116c6e25730bb4 100644 (file)
@@ -1,6 +1,6 @@
 /*
  * ngIRCd -- The Next Generation IRC Daemon
- * Copyright (c)2001,2002 by Alexander Barton (alex@barton.de)
+ * Copyright (c)2001-2005 Alexander Barton (alex@barton.de)
  *
  * 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
@@ -14,7 +14,7 @@
 
 #include "portab.h"
 
-static char UNUSED id[] = "$Id: irc-mode.c,v 1.23 2002/12/16 23:06:46 alex Exp $";
+static char UNUSED id[] = "$Id: irc-mode.c,v 1.38 2005/03/05 11:44:01 alex Exp $";
 
 #include "imp.h"
 #include <assert.h>
@@ -91,6 +91,7 @@ Client_Mode( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CLIENT *Target )
        CHAR the_modes[COMMAND_LEN], x[2], *mode_ptr;
        BOOLEAN ok, set;
        INT mode_arg;
+       size_t len;
 
        /* Is the client allowed to request or change the modes? */
        if( Client_Type( Client ) == CLIENT_USER )
@@ -134,15 +135,17 @@ Client_Mode( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CLIENT *Target )
                                if((( *mode_ptr == '+' ) && ( ! set )) || (( *mode_ptr == '-' ) && ( set )))
                                {
                                        /* Action modifier ("+"/"-") must be changed ... */
-                                       if(( the_modes[strlen( the_modes ) - 1] == '+' ) || ( the_modes[strlen( the_modes ) - 1] == '-' ))
+                                       len = strlen( the_modes ) - 1;
+                                       if(( the_modes[len] == '+' ) || ( the_modes[len] == '-' ))
                                        {
                                                /* Adjust last action modifier in result */
-                                               the_modes[strlen( the_modes ) - 1] = *mode_ptr;
+                                               the_modes[len] = *mode_ptr;
                                        }
                                        else
                                        {
                                                /* Append modifier character to result string */
-                                               x[0] = *mode_ptr; strcat( the_modes, x );
+                                               x[0] = *mode_ptr;
+                                               strlcat( the_modes, x, sizeof( the_modes ));
                                        }
                                        if( *mode_ptr == '+' ) set = TRUE;
                                        else set = FALSE;
@@ -154,28 +157,34 @@ Client_Mode( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CLIENT *Target )
                x[0] = '\0';
                switch( *mode_ptr )
                {
-                       case 'i':
-                               /* Invisible */
-                               x[0] = 'i';
+                       case 'i': /* Invisible */
+                       case 's': /* Server messages */
+                               x[0] = *mode_ptr;
                                break;
-                       case 'o':
-                               /* IRC operator (only unsetable!) */
-                               if( ! set )
+
+                       case 'a': /* Away */
+                               if( Client_Type( Client ) == CLIENT_SERVER )
+                               {
+                                       x[0] = 'a';
+                                       Client_SetAway( Client, 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 setable) */
-                               if( set ) x[0] = 'r';
+
+                       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 's':
-                               /* Server messages */
-                               x[0] = 's';
-                               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 );
@@ -190,13 +199,13 @@ Client_Mode( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CLIENT *Target )
                if( set )
                {
                        /* Set mode */
-                       if( Client_ModeAdd( Target, x[0] )) strcat( the_modes, x );
+                       if( Client_ModeAdd( Target, x[0] )) strlcat( the_modes, x, sizeof( the_modes ));
 
                }
                else
                {
                        /* Unset mode */
-                       if( Client_ModeDel( Target, x[0] )) strcat( the_modes, x );
+                       if( Client_ModeDel( Target, x[0] )) strlcat( the_modes, x, sizeof( the_modes ));
                }               
        }
 client_exit:
@@ -205,7 +214,8 @@ client_exit:
        if( the_modes[1] )
        {
                /* Remoce needless action modifier characters */
-               if(( the_modes[strlen( the_modes ) - 1] == '+' ) || ( the_modes[strlen( the_modes ) - 1] == '-' )) the_modes[strlen( the_modes ) - 1] = '\0';
+               len = strlen( the_modes ) - 1;
+               if(( the_modes[len] == '+' ) || ( the_modes[len] == '-' )) the_modes[len] = '\0';
 
                if( Client_Type( Client ) == CLIENT_SERVER )
                {
@@ -215,12 +225,13 @@ client_exit:
                else
                {
                        /* Send reply to client and inform other servers */
-                       ok = IRC_WriteStrClientPrefix( 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 );
                }
                Log( LOG_DEBUG, "User \"%s\": Mode change, now \"%s\".", Client_Mask( Target ), Client_Modes( Target ));
        }
-               
+       
+       IRC_SetPenalty( Client, 1 );    
        return ok;
 } /* Client_Mode */
 
@@ -235,13 +246,45 @@ Channel_Mode( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CHANNEL *Channel )
        INT mode_arg, arg_arg;
        CLIENT *client;
        LONG l;
+       size_t len;
 
        /* Mode request: let's answer it :-) */
-       if( Req->argc == 1 ) return IRC_WriteStrClient( Origin, RPL_CHANNELMODEIS_MSG, Client_ID( Origin ), Channel_Name( Channel ), Channel_Modes( Channel ));
+       if( Req->argc == 1 )
+       {
+               /* Member or not? -- That's the question! */
+               if( ! Channel_IsMemberOf( Channel, Origin )) return IRC_WriteStrClient( Origin, RPL_CHANNELMODEIS_MSG, Client_ID( Origin ), Channel_Name( Channel ), Channel_Modes( Channel ));
+
+               /* The sender is a member: generate extended reply */
+               strlcpy( the_modes, Channel_Modes( Channel ), sizeof( the_modes ));
+               mode_ptr = the_modes;
+               strcpy( the_args, "" );
+               while( *mode_ptr )
+               {
+                       switch( *mode_ptr )
+                       {
+                               case 'l':
+                                       snprintf( argadd, sizeof( argadd ), " %ld", Channel_MaxUsers( Channel ));
+                                       strlcat( the_args, argadd, sizeof( the_args ));
+                                       break;
+                               case 'k':
+                                       strlcat( the_args, " ", sizeof( the_args ));
+                                       strlcat( the_args, Channel_Key( Channel ), sizeof( the_args ));
+                                       break;
+                       }
+                       mode_ptr++;
+               }
+               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 );
+       }
 
        /* 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 ));
+
+               /* Is he channel operator? */
                if( strchr( Channel_UserModes( Channel, Origin ), 'o' )) modeok = TRUE;
                else modeok = FALSE;
                if( Conf_OperCanMode )
@@ -292,15 +335,17 @@ Channel_Mode( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CHANNEL *Channel )
                                if((( *mode_ptr == '+' ) && ( ! set )) || (( *mode_ptr == '-' ) && ( set )))
                                {
                                        /* Action modifier ("+"/"-") must be changed ... */
-                                       if(( the_modes[strlen( the_modes ) - 1] == '+' ) || ( the_modes[strlen( the_modes ) - 1] == '-' ))
+                                       len = strlen( the_modes ) - 1;
+                                       if(( the_modes[len] == '+' ) || ( the_modes[len] == '-' ))
                                        {
                                                /* Adjust last action modifier in result */
-                                               the_modes[strlen( the_modes ) - 1] = *mode_ptr;
+                                               the_modes[len] = *mode_ptr;
                                        }
                                        else
                                        {
                                                /* Append modifier character to result string */
-                                               x[0] = *mode_ptr; strcat( the_modes, x );
+                                               x[0] = *mode_ptr;
+                                               strlcat( the_modes, x, sizeof( the_modes ));
                                        }
                                        if( *mode_ptr == '+' ) set = TRUE;
                                        else set = FALSE;
@@ -317,62 +362,18 @@ Channel_Mode( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CHANNEL *Channel )
                client = NULL;
                switch( *mode_ptr )
                {
-                       /* Channel modes */
-                       case 'i':
-                               /* Invite-Only */
-                               if( modeok ) x[0] = 'i';
-                               else ok = IRC_WriteStrClient( Origin, ERR_CHANOPRIVSNEEDED_MSG, Client_ID( Origin ), Channel_Name( Channel ));
-                               break;
-                       case 'm':
-                               /* Moderated */
-                               if( modeok ) x[0] = 'm';
-                               else ok = IRC_WriteStrClient( Origin, ERR_CHANOPRIVSNEEDED_MSG, Client_ID( Origin ), Channel_Name( Channel ));
-                               break;
-                       case 'n':
-                               /* kein Schreiben in den Channel von aussen */
-                               if( modeok ) x[0] = 'n';
-                               else ok = IRC_WriteStrClient( Origin, ERR_CHANOPRIVSNEEDED_MSG, Client_ID( Origin ), Channel_Name( Channel ));
-                               break;
-                       case 't':
-                               /* Topic Lock */
-                               if( modeok ) x[0] = 't';
-                               else ok = IRC_WriteStrClient( Origin, ERR_CHANOPRIVSNEEDED_MSG, Client_ID( Origin ), Channel_Name( Channel ));
-                               break;
-                       case 'P':
-                               /* Persistent channel */
-                               if( modeok )
-                               {
-                                       if( set && ( ! Client_OperByMe( Client )))
-                                       {
-                                               /* Only IRC operators are allowed to set P mode */
-                                               ok = IRC_WriteStrClient( Origin, ERR_NOPRIVILEGES_MSG, Client_ID( Origin ));
-                                       }
-                                       else x[0] = 'P';
-                               }
+                       /* --- Channel modes --- */
+
+                       case 'i': /* Invite only */
+                       case 'm': /* Moderated */
+                       case 'n': /* Only members can write */
+                       case 's': /* Secret channel */
+                       case 't': /* Topic locked */
+                               if( modeok ) x[0] = *mode_ptr;
                                else ok = IRC_WriteStrClient( Origin, ERR_CHANOPRIVSNEEDED_MSG, Client_ID( Origin ), Channel_Name( Channel ));
                                break;
 
-                       /* Channel user modes */
-                       case 'o':
-                               /* Channel operator */
-                       case 'v':
-                               /* Voice */
-                               if( arg_arg > mode_arg )
-                               {
-                                       if( modeok )
-                                       {
-                                               client = Client_Search( Req->argv[arg_arg] );
-                                               if( client ) x[0] = *mode_ptr;
-                                               else ok = 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 ));
-                                       Req->argv[arg_arg][0] = '\0';
-                                       arg_arg++;
-                               }
-                               else ok = IRC_WriteStrClient( Origin, ERR_NEEDMOREPARAMS_MSG, Client_ID( Origin ), Req->command );
-                               break;
-                       case 'k':
-                               /* Channel key */
+                       case 'k': /* Channel key */
                                if( ! set )
                                {
                                        if( modeok ) x[0] = *mode_ptr;
@@ -385,7 +386,7 @@ Channel_Mode( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CHANNEL *Channel )
                                        {
                                                Channel_ModeDel( Channel, 'k' );
                                                Channel_SetKey( Channel, Req->argv[arg_arg] );
-                                               strcpy( argadd, Channel_Key( Channel ));
+                                               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 ));
@@ -394,8 +395,8 @@ Channel_Mode( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CHANNEL *Channel )
                                }
                                else ok = IRC_WriteStrClient( Origin, ERR_NEEDMOREPARAMS_MSG, Client_ID( Origin ), Req->command );
                                break;
-                       case 'l':
-                               /* Member limit */
+
+                       case 'l': /* Member limit */
                                if( ! set )
                                {
                                        if( modeok ) x[0] = *mode_ptr;
@@ -411,7 +412,7 @@ Channel_Mode( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CHANNEL *Channel )
                                                {
                                                        Channel_ModeDel( Channel, 'l' );
                                                        Channel_SetMaxUsers( Channel, l );
-                                                       sprintf( argadd, "%ld", l );
+                                                       snprintf( argadd, sizeof( argadd ), "%ld", l );
                                                        x[0] = *mode_ptr;
                                                }
                                        }
@@ -422,9 +423,41 @@ Channel_Mode( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CHANNEL *Channel )
                                else ok = IRC_WriteStrClient( Origin, ERR_NEEDMOREPARAMS_MSG, Client_ID( Origin ), Req->command );
                                break;
 
-                       /* Channel lists */
-                       case 'I':
-                               /* Invite lists */
+                       case 'P': /* Persistent channel */
+                               if( modeok )
+                               {
+                                       if( set && ( ! Client_OperByMe( Client )))
+                                       {
+                                               /* Only IRC operators are allowed to set P mode */
+                                               ok = IRC_WriteStrClient( Origin, ERR_NOPRIVILEGES_MSG, Client_ID( Origin ));
+                                       }
+                                       else x[0] = 'P';
+                               }
+                               else ok = IRC_WriteStrClient( Origin, ERR_CHANOPRIVSNEEDED_MSG, Client_ID( Origin ), Channel_Name( Channel ));
+                               break;
+
+                       /* --- Channel user modes --- */
+
+                       case 'o': /* Channel operator */
+                       case 'v': /* Voice */
+                               if( arg_arg > mode_arg )
+                               {
+                                       if( modeok )
+                                       {
+                                               client = Client_Search( Req->argv[arg_arg] );
+                                               if( client ) x[0] = *mode_ptr;
+                                               else ok = 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 ));
+                                       Req->argv[arg_arg][0] = '\0';
+                                       arg_arg++;
+                               }
+                               else ok = IRC_WriteStrClient( Origin, ERR_NEEDMOREPARAMS_MSG, Client_ID( Origin ), Req->command );
+                               break;
+
+                       /* --- Channel lists --- */
+
+                       case 'I': /* Invite lists */
                                if( arg_arg > mode_arg )
                                {
                                        /* modify list */
@@ -439,8 +472,8 @@ Channel_Mode( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CHANNEL *Channel )
                                }
                                else Lists_ShowInvites( Origin, Channel );
                                break;
-                       case 'b':
-                               /* Ban lists */
+
+                       case 'b': /* Ban lists */
                                if( arg_arg > mode_arg )
                                {
                                        /* modify list */
@@ -467,6 +500,13 @@ Channel_Mode( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CHANNEL *Channel )
                /* Is there a valid mode change? */
                if( ! x[0] ) continue;
 
+               /* 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;
+                       continue;
+               }
+
                if( set )
                {
                        /* Set mode */
@@ -475,8 +515,9 @@ Channel_Mode( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CHANNEL *Channel )
                                /* Channel-User-Mode */
                                if( Channel_UserModeAdd( Channel, client, x[0] ))
                                {
-                                       strcat( the_args, Client_ID( client ));
-                                       strcat( the_args, " " ); strcat( the_modes, x );
+                                       strlcat( the_args, Client_ID( client ), sizeof( the_args ));
+                                       strlcat( the_args, " ", sizeof( the_args ));
+                                       strlcat( the_modes, x, sizeof( the_modes ));
                                        Log( LOG_DEBUG, "User \"%s\": Mode change on %s, now \"%s\"", Client_Mask( client ), Channel_Name( Channel ), Channel_UserModes( Channel, client ));
                                }
                        }
@@ -485,7 +526,7 @@ Channel_Mode( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CHANNEL *Channel )
                                /* Channel-Mode */
                                if( Channel_ModeAdd( Channel, x[0] ))
                                {
-                                       strcat( the_modes, x );
+                                       strlcat( the_modes, x, sizeof( the_modes ));
                                        Log( LOG_DEBUG, "Channel %s: Mode change, now \"%s\".", Channel_Name( Channel ), Channel_Modes( Channel ));
                                }
                        }
@@ -498,8 +539,9 @@ Channel_Mode( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CHANNEL *Channel )
                                /* Channel-User-Mode */
                                if( Channel_UserModeDel( Channel, client, x[0] ))
                                {
-                                       strcat( the_args, Client_ID( client ));
-                                       strcat( the_args, " " ); strcat( the_modes, x );
+                                       strlcat( the_args, Client_ID( client ), sizeof( the_args ));
+                                       strlcat( the_args, " ", sizeof( the_args ));
+                                       strlcat( the_modes, x, sizeof( the_modes ));
                                        Log( LOG_DEBUG, "User \"%s\": Mode change on %s, now \"%s\"", Client_Mask( client ), Channel_Name( Channel ), Channel_UserModes( Channel, client ));
                                }
                        }
@@ -508,7 +550,7 @@ Channel_Mode( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CHANNEL *Channel )
                                /* Channel-Mode */
                                if( Channel_ModeDel( Channel, x[0] ))
                                {
-                                       strcat( the_modes, x );
+                                       strlcat( the_modes, x, sizeof( the_modes ));
                                        Log( LOG_DEBUG, "Channel %s: Mode change, now \"%s\".", Channel_Name( Channel ), Channel_Modes( Channel ));
                                }
                        }
@@ -517,8 +559,9 @@ Channel_Mode( CLIENT *Client, REQUEST *Req, CLIENT *Origin, CHANNEL *Channel )
                /* Are there additional arguments to add? */
                if( argadd[0] )
                {
-                       if( the_args[strlen( the_args ) - 1] != ' ' ) strcat( the_args, " " );
-                       strcat( the_args, argadd );
+                       len = strlen( the_args ) - 1;
+                       if( the_args[len] != ' ' ) strlcat( the_args, " ", sizeof( the_args ));
+                       strlcat( the_args, argadd, sizeof( the_args ));
                }
        }
 chan_exit:
@@ -527,7 +570,8 @@ chan_exit:
        if( the_modes[1] )
        {
                /* Clean up mode string */
-               if(( the_modes[strlen( the_modes ) - 1] == '+' ) || ( the_modes[strlen( the_modes ) - 1] == '-' )) the_modes[strlen( the_modes ) - 1] = '\0';
+               len = strlen( the_modes ) - 1;
+               if(( the_modes[len] == '+' ) || ( the_modes[len] == '-' )) the_modes[len] = '\0';
 
                /* Clean up argument string if there are none */
                if( ! the_args[1] ) the_args[0] = '\0';
@@ -547,6 +591,7 @@ chan_exit:
                }
        }
 
+       IRC_SetPenalty( Client, 1 );
        return CONNECTED;
 } /* Channel_Mode */
 
@@ -564,13 +609,14 @@ IRC_AWAY( CLIENT *Client, REQUEST *Req )
        {
                /* AWAY setzen */
                Client_SetAway( Client, Req->argv[0] );
+               Client_ModeAdd( Client, 'a' );
                IRC_WriteStrServersPrefix( Client, Client, "MODE %s :+a", Client_ID( Client ));
                return IRC_WriteStrClient( Client, RPL_NOWAWAY_MSG, Client_ID( Client ));
        }
        else
        {
                /* AWAY loeschen */
-               Client_SetAway( Client, NULL );
+               Client_ModeDel( Client, 'a' );
                IRC_WriteStrServersPrefix( Client, Client, "MODE %s :-a", Client_ID( Client ));
                return IRC_WriteStrClient( Client, RPL_UNAWAY_MSG, Client_ID( Client ));
        }
@@ -581,6 +627,7 @@ LOCAL BOOLEAN
 Add_Invite( CLIENT *Prefix, CLIENT *Client, CHANNEL *Channel, CHAR *Pattern )
 {
        CHAR *mask;
+       BOOLEAN already;
 
        assert( Client != NULL );
        assert( Channel != NULL );
@@ -588,7 +635,12 @@ Add_Invite( CLIENT *Prefix, CLIENT *Client, CHANNEL *Channel, CHAR *Pattern )
 
        mask = Lists_MakeMask( Pattern );
 
-       if( ! Lists_AddInvited( Prefix, mask, Channel, FALSE )) return CONNECTED;
+       already = Lists_IsInviteEntry( mask, Channel );
+       
+       if( ! Lists_AddInvited( mask, Channel, FALSE )) return CONNECTED;
+       
+       if(( Client_Type( Prefix ) == CLIENT_SERVER ) && ( already == TRUE )) return CONNECTED;
+
        return Send_ListChange( "+I", Prefix, Client, Channel, mask );
 } /* Add_Invite */
 
@@ -597,6 +649,7 @@ LOCAL BOOLEAN
 Add_Ban( CLIENT *Prefix, CLIENT *Client, CHANNEL *Channel, CHAR *Pattern )
 {
        CHAR *mask;
+       BOOLEAN already;
 
        assert( Client != NULL );
        assert( Channel != NULL );
@@ -604,7 +657,12 @@ Add_Ban( CLIENT *Prefix, CLIENT *Client, CHANNEL *Channel, CHAR *Pattern )
 
        mask = Lists_MakeMask( Pattern );
 
-       if( ! Lists_AddBanned( Prefix, mask, Channel )) return CONNECTED;
+       already = Lists_IsBanEntry( mask, Channel );
+
+       if( ! Lists_AddBanned( mask, Channel )) return CONNECTED;
+
+       if(( Client_Type( Prefix ) == CLIENT_SERVER ) && ( already == TRUE )) return CONNECTED;
+
        return Send_ListChange( "+b", Prefix, Client, Channel, mask );
 } /* Add_Ban */