modules/m_knock.c

   1 /*
   2  *  ircd-ratbox: A slightly useful ircd.
   3  *  m_knock.c: Requests to be invited to a channel.
   4  *
   5  *  Copyright (C) 1996-2002 Hybrid Development Team
   6  *  Copyright (C) 2002-2005 ircd-ratbox development team
   7  *
   8  *  This program is free software; you can redistribute it and/or modify
   9  *  it under the terms of the GNU General Public License as published by
  10  *  the Free Software Foundation; either version 2 of the License, or
  11  *  (at your option) any later version.
  12  *
  13  *  This program is distributed in the hope that it will be useful,
  14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  *  GNU General Public License for more details.
  17  *
  18  *  You should have received a copy of the GNU General Public License
  19  *  along with this program; if not, write to the Free Software
  20  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
  21  *  USA
  22  *
  23  *  $Id: m_knock.c 3570 2007-09-09 19:19:23Z jilles $
  24  */
  25
  26 #include "stdinc.h"
  27 #include "channel.h"
  28 #include "client.h"
  29 #include "hash.h"
  30 #include "match.h"
  31 #include "ircd.h"
  32 #include "numeric.h"
  33 #include "send.h"
  34 #include "s_conf.h"
  35 #include "msg.h"
  36 #include "parse.h"
  37 #include "modules.h"
  38 #include "s_serv.h"
  39 #include "supported.h"
  40
  41 static int m_knock(struct MsgBuf *, struct Client *, struct Client *, int, const char **);
  42
  43 struct Message knock_msgtab = {
  44         "KNOCK", 0, 0, 0, 0,
  45         {mg_unreg, {m_knock, 2}, {m_knock, 2}, mg_ignore, mg_ignore, {m_knock, 2}}
  46 };
  47
  48 static int
  49 _modinit(void)
  50 {
  51         add_isupport("KNOCK", isupport_boolean, &ConfigChannel.use_knock);
  52         return 0;
  53 }
  54
  55 static void
  56 _moddeinit(void)
  57 {
  58         delete_isupport("KNOCK");
  59 }
  60
  61 mapi_clist_av1 knock_clist[] = { &knock_msgtab, NULL };
  62 DECLARE_MODULE_AV1(knock, _modinit, _moddeinit, knock_clist, NULL, NULL, "$Revision: 3570 $");
  63
  64 /* m_knock
  65  *    parv[1] = channel
  66  *
  67  *  The KNOCK command has the following syntax:
  68  *   :<sender> KNOCK <channel>
  69  *
  70  *  If a user is not banned from the channel they can use the KNOCK
  71  *  command to have the server NOTICE the channel operators notifying
  72  *  they would like to join.  Helpful if the channel is invite-only, the
  73  *  key is forgotten, or the channel is full (INVITE can bypass each one
  74  *  of these conditions.  Concept by Dianora <db@db.net> and written by
  75  *  <anonymous>
  76  */
  77 static int
  78 m_knock(struct MsgBuf *msgbuf_p, struct Client *client_p, struct Client *source_p, int parc, const char *parv[])
  79 {
  80         struct Channel *chptr;
  81         char *p, *name;
  82
  83         if(MyClient(source_p) && ConfigChannel.use_knock == 0)
  84         {
  85                 sendto_one(source_p, form_str(ERR_KNOCKDISABLED),
  86                            me.name, source_p->name);
  87                 return 0;
  88         }
  89
  90         name = LOCAL_COPY(parv[1]);
  91
  92         /* dont allow one knock to multiple chans */
  93         if((p = strchr(name, ',')))
  94                 *p = '\0';
  95
  96         if((chptr = find_channel(name)) == NULL)
  97         {
  98                 sendto_one_numeric(source_p, ERR_NOSUCHCHANNEL,
  99                                    form_str(ERR_NOSUCHCHANNEL), name);
 100                 return 0;
 101         }
 102
 103         if(IsMember(source_p, chptr))
 104         {
 105                 if(MyClient(source_p))
 106                         sendto_one(source_p, form_str(ERR_KNOCKONCHAN),
 107                                    me.name, source_p->name, name);
 108                 return 0;
 109         }
 110
 111         if(!((chptr->mode.mode & MODE_INVITEONLY) || (*chptr->mode.key) ||
 112              (chptr->mode.limit &&
 113               rb_dlink_list_length(&chptr->members) >= (unsigned long)chptr->mode.limit)))
 114         {
 115                 sendto_one_numeric(source_p, ERR_CHANOPEN,
 116                                    form_str(ERR_CHANOPEN), name);
 117                 return 0;
 118         }
 119
 120         /* cant knock to a +p channel */
 121         if(HiddenChannel(chptr))
 122         {
 123                 sendto_one_numeric(source_p, ERR_CANNOTSENDTOCHAN,
 124                                    form_str(ERR_CANNOTSENDTOCHAN), name);
 125                 return 0;
 126         }
 127
 128
 129         if(MyClient(source_p))
 130         {
 131                 /* don't allow a knock if the user is banned */
 132                 if(is_banned(chptr, source_p, NULL, NULL, NULL, NULL) == CHFL_BAN ||
 133                         is_quieted(chptr, source_p, NULL, NULL, NULL) == CHFL_BAN)
 134                 {
 135                         sendto_one_numeric(source_p, ERR_CANNOTSENDTOCHAN,
 136                                            form_str(ERR_CANNOTSENDTOCHAN), name);
 137                         return 0;
 138                 }
 139
 140                 /* local flood protection:
 141                  * allow one knock per user per knock_delay
 142                  * allow one knock per channel per knock_delay_channel
 143                  */
 144                 if(!IsOper(source_p) &&
 145                    (source_p->localClient->last_knock + ConfigChannel.knock_delay) > rb_current_time())
 146                 {
 147                         sendto_one(source_p, form_str(ERR_TOOMANYKNOCK),
 148                                         me.name, source_p->name, name, "user");
 149                         return 0;
 150                 }
 151                 else if((chptr->last_knock + ConfigChannel.knock_delay_channel) > rb_current_time())
 152                 {
 153                         sendto_one(source_p, form_str(ERR_TOOMANYKNOCK),
 154                                         me.name, source_p->name, name, "channel");
 155                         return 0;
 156                 }
 157
 158                 /* ok, we actually can send the knock, tell client */
 159                 source_p->localClient->last_knock = rb_current_time();
 160
 161                 sendto_one(source_p, form_str(RPL_KNOCKDLVR),
 162                            me.name, source_p->name, name);
 163         }
 164
 165         chptr->last_knock = rb_current_time();
 166
 167         if(ConfigChannel.use_knock)
 168                 sendto_channel_local(chptr->mode.mode & MODE_FREEINVITE ? ALL_MEMBERS : ONLY_CHANOPS,
 169                                      chptr, form_str(RPL_KNOCK),
 170                                      me.name, name, name, source_p->name,
 171                                      source_p->username, source_p->host);
 172
 173         sendto_server(client_p, chptr, CAP_KNOCK|CAP_TS6, NOCAPS,
 174                       ":%s KNOCK %s", use_id(source_p), name);
 175         sendto_server(client_p, chptr, CAP_KNOCK, CAP_TS6,
 176                       ":%s KNOCK %s", source_p->name, name);
 177         return 0;
 178 }
 179