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 const char knock_desc[] = "Provides the KNOCK command to ask for an invite to an invite-only channel";
  40
  41 static void 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
  63 DECLARE_MODULE_AV2(knock, _modinit, _moddeinit, knock_clist, NULL, NULL, NULL, NULL, knock_desc);
  64
  65 /* m_knock
  66  *    parv[1] = channel
  67  *
  68  *  The KNOCK command has the following syntax:
  69  *   :<sender> KNOCK <channel>
  70  *
  71  *  If a user is not banned from the channel they can use the KNOCK
  72  *  command to have the server NOTICE the channel operators notifying
  73  *  they would like to join.  Helpful if the channel is invite-only, the
  74  *  key is forgotten, or the channel is full (INVITE can bypass each one
  75  *  of these conditions.  Concept by Dianora <db@db.net> and written by
  76  *  <anonymous>
  77  */
  78 static void
  79 m_knock(struct MsgBuf *msgbuf_p, struct Client *client_p, struct Client *source_p, int parc, const char *parv[])
  80 {
  81         struct Channel *chptr;
  82         char *p, *name;
  83
  84         if(MyClient(source_p) && ConfigChannel.use_knock == 0)
  85         {
  86                 sendto_one(source_p, form_str(ERR_KNOCKDISABLED),
  87                            me.name, source_p->name);
  88                 return;
  89         }
  90
  91         name = LOCAL_COPY(parv[1]);
  92
  93         /* dont allow one knock to multiple chans */
  94         if((p = strchr(name, ',')))
  95                 *p = '\0';
  96
  97         if((chptr = find_channel(name)) == NULL)
  98         {
  99                 sendto_one_numeric(source_p, ERR_NOSUCHCHANNEL,
 100                                    form_str(ERR_NOSUCHCHANNEL), name);
 101                 return;
 102         }
 103
 104         if(IsMember(source_p, chptr))
 105         {
 106                 if(MyClient(source_p))
 107                         sendto_one(source_p, form_str(ERR_KNOCKONCHAN),
 108                                    me.name, source_p->name, name);
 109                 return;
 110         }
 111
 112         if(!((chptr->mode.mode & MODE_INVITEONLY) || (*chptr->mode.key) ||
 113              (chptr->mode.limit &&
 114               rb_dlink_list_length(&chptr->members) >= (unsigned long)chptr->mode.limit)))
 115         {
 116                 sendto_one_numeric(source_p, ERR_CHANOPEN,
 117                                    form_str(ERR_CHANOPEN), name);
 118                 return;
 119         }
 120
 121         /* cant knock to a +p channel */
 122         if(HiddenChannel(chptr))
 123         {
 124                 sendto_one_numeric(source_p, ERR_CANNOTSENDTOCHAN,
 125                                    form_str(ERR_CANNOTSENDTOCHAN), name);
 126                 return;
 127         }
 128
 129
 130         if(MyClient(source_p))
 131         {
 132                 /* don't allow a knock if the user is banned */
 133                 if(is_banned(chptr, source_p, NULL, NULL, NULL, NULL) == CHFL_BAN ||
 134                         is_quieted(chptr, source_p, NULL, NULL, NULL) == CHFL_BAN)
 135                 {
 136                         sendto_one_numeric(source_p, ERR_CANNOTSENDTOCHAN,
 137                                            form_str(ERR_CANNOTSENDTOCHAN), name);
 138                         return;
 139                 }
 140
 141                 /* local flood protection:
 142                  * allow one knock per user per knock_delay
 143                  * allow one knock per channel per knock_delay_channel
 144                  */
 145                 if(!IsOper(source_p) &&
 146                    (source_p->localClient->last_knock + ConfigChannel.knock_delay) > rb_current_time())
 147                 {
 148                         sendto_one(source_p, form_str(ERR_TOOMANYKNOCK),
 149                                         me.name, source_p->name, name, "user");
 150                         return;
 151                 }
 152                 else if((chptr->last_knock + ConfigChannel.knock_delay_channel) > rb_current_time())
 153                 {
 154                         sendto_one(source_p, form_str(ERR_TOOMANYKNOCK),
 155                                         me.name, source_p->name, name, "channel");
 156                         return;
 157                 }
 158
 159                 /* ok, we actually can send the knock, tell client */
 160                 source_p->localClient->last_knock = rb_current_time();
 161
 162                 sendto_one(source_p, form_str(RPL_KNOCKDLVR),
 163                            me.name, source_p->name, name);
 164         }
 165
 166         chptr->last_knock = rb_current_time();
 167
 168         if(ConfigChannel.use_knock)
 169                 sendto_channel_local(source_p, (chptr->mode.mode & MODE_FREEINVITE) ? ALL_MEMBERS : ONLY_CHANOPS,
 170                                      chptr, form_str(RPL_KNOCK),
 171                                      me.name, name, name, source_p->name,
 172                                      source_p->username, source_p->host);
 173
 174         sendto_server(client_p, chptr, CAP_KNOCK|CAP_TS6, NOCAPS,
 175                       ":%s KNOCK %s", use_id(source_p), name);
 176         sendto_server(client_p, chptr, CAP_KNOCK, CAP_TS6,
 177                       ":%s KNOCK %s", source_p->name, name);
 178 }
 179