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
  24 #include "stdinc.h"
  25 #include "channel.h"
  26 #include "client.h"
  27 #include "hash.h"
  28 #include "match.h"
  29 #include "ircd.h"
  30 #include "numeric.h"
  31 #include "send.h"
  32 #include "s_conf.h"
  33 #include "msg.h"
  34 #include "parse.h"
  35 #include "modules.h"
  36 #include "s_serv.h"
  37 #include "supported.h"
  38
  39 static int m_knock(struct MsgBuf *, struct Client *, struct Client *, int, const char **);
  40
  41 struct Message knock_msgtab = {
  42         "KNOCK", 0, 0, 0, 0,
  43         {mg_unreg, {m_knock, 2}, {m_knock, 2}, mg_ignore, mg_ignore, {m_knock, 2}}
  44 };
  45
  46 static int
  47 _modinit(void)
  48 {
  49         add_isupport("KNOCK", isupport_boolean, &ConfigChannel.use_knock);
  50         return 0;
  51 }
  52
  53 static void
  54 _moddeinit(void)
  55 {
  56         delete_isupport("KNOCK");
  57 }
  58
  59 mapi_clist_av1 knock_clist[] = { &knock_msgtab, NULL };
  60 DECLARE_MODULE_AV2(knock, _modinit, _moddeinit, knock_clist, NULL, NULL, NULL, NULL, NULL);
  61
  62 /* m_knock
  63  *    parv[1] = channel
  64  *
  65  *  The KNOCK command has the following syntax:
  66  *   :<sender> KNOCK <channel>
  67  *
  68  *  If a user is not banned from the channel they can use the KNOCK
  69  *  command to have the server NOTICE the channel operators notifying
  70  *  they would like to join.  Helpful if the channel is invite-only, the
  71  *  key is forgotten, or the channel is full (INVITE can bypass each one
  72  *  of these conditions.  Concept by Dianora <db@db.net> and written by
  73  *  <anonymous>
  74  */
  75 static int
  76 m_knock(struct MsgBuf *msgbuf_p, struct Client *client_p, struct Client *source_p, int parc, const char *parv[])
  77 {
  78         struct Channel *chptr;
  79         char *p, *name;
  80
  81         if(MyClient(source_p) && ConfigChannel.use_knock == 0)
  82         {
  83                 sendto_one(source_p, form_str(ERR_KNOCKDISABLED),
  84                            me.name, source_p->name);
  85                 return 0;
  86         }
  87
  88         name = LOCAL_COPY(parv[1]);
  89
  90         /* dont allow one knock to multiple chans */
  91         if((p = strchr(name, ',')))
  92                 *p = '\0';
  93
  94         if((chptr = find_channel(name)) == NULL)
  95         {
  96                 sendto_one_numeric(source_p, ERR_NOSUCHCHANNEL,
  97                                    form_str(ERR_NOSUCHCHANNEL), name);
  98                 return 0;
  99         }
 100
 101         if(IsMember(source_p, chptr))
 102         {
 103                 if(MyClient(source_p))
 104                         sendto_one(source_p, form_str(ERR_KNOCKONCHAN),
 105                                    me.name, source_p->name, name);
 106                 return 0;
 107         }
 108
 109         if(!((chptr->mode.mode & MODE_INVITEONLY) || (*chptr->mode.key) ||
 110              (chptr->mode.limit &&
 111               rb_dlink_list_length(&chptr->members) >= (unsigned long)chptr->mode.limit)))
 112         {
 113                 sendto_one_numeric(source_p, ERR_CHANOPEN,
 114                                    form_str(ERR_CHANOPEN), name);
 115                 return 0;
 116         }
 117
 118         /* cant knock to a +p channel */
 119         if(HiddenChannel(chptr))
 120         {
 121                 sendto_one_numeric(source_p, ERR_CANNOTSENDTOCHAN,
 122                                    form_str(ERR_CANNOTSENDTOCHAN), name);
 123                 return 0;
 124         }
 125
 126
 127         if(MyClient(source_p))
 128         {
 129                 /* don't allow a knock if the user is banned */
 130                 if(is_banned(chptr, source_p, NULL, NULL, NULL, NULL) == CHFL_BAN ||
 131                         is_quieted(chptr, source_p, NULL, NULL, NULL) == CHFL_BAN)
 132                 {
 133                         sendto_one_numeric(source_p, ERR_CANNOTSENDTOCHAN,
 134                                            form_str(ERR_CANNOTSENDTOCHAN), name);
 135                         return 0;
 136                 }
 137
 138                 /* local flood protection:
 139                  * allow one knock per user per knock_delay
 140                  * allow one knock per channel per knock_delay_channel
 141                  */
 142                 if(!IsOper(source_p) &&
 143                    (source_p->localClient->last_knock + ConfigChannel.knock_delay) > rb_current_time())
 144                 {
 145                         sendto_one(source_p, form_str(ERR_TOOMANYKNOCK),
 146                                         me.name, source_p->name, name, "user");
 147                         return 0;
 148                 }
 149                 else if((chptr->last_knock + ConfigChannel.knock_delay_channel) > rb_current_time())
 150                 {
 151                         sendto_one(source_p, form_str(ERR_TOOMANYKNOCK),
 152                                         me.name, source_p->name, name, "channel");
 153                         return 0;
 154                 }
 155
 156                 /* ok, we actually can send the knock, tell client */
 157                 source_p->localClient->last_knock = rb_current_time();
 158
 159                 sendto_one(source_p, form_str(RPL_KNOCKDLVR),
 160                            me.name, source_p->name, name);
 161         }
 162
 163         chptr->last_knock = rb_current_time();
 164
 165         if(ConfigChannel.use_knock)
 166                 sendto_channel_local(chptr->mode.mode & MODE_FREEINVITE ? ALL_MEMBERS : ONLY_CHANOPS,
 167                                      chptr, form_str(RPL_KNOCK),
 168                                      me.name, name, name, source_p->name,
 169                                      source_p->username, source_p->host);
 170
 171         sendto_server(client_p, chptr, CAP_KNOCK|CAP_TS6, NOCAPS,
 172                       ":%s KNOCK %s", use_id(source_p), name);
 173         sendto_server(client_p, chptr, CAP_KNOCK, CAP_TS6,
 174                       ":%s KNOCK %s", source_p->name, name);
 175         return 0;
 176 }
 177