src/modules/m_joinflood.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd: (C) 2002-2009 InspIRCd Development Team
   6  * See: http://wiki.inspircd.org/Credits
   7  *
   8  * This program is free but copyrighted software; see
   9  *            the file COPYING for details.
  10  *
  11  * ---------------------------------------------------
  12  */
  13
  14 #include "inspircd.h"
  15
  16 /* $ModDesc: Provides channel mode +j (join flood protection) */
  17
  18 /** Holds settings and state associated with channel mode +j
  19  */
  20 class joinfloodsettings : public classbase
  21 {
  22  private:
  23         InspIRCd* ServerInstance;
  24  public:
  25         int secs;
  26         int joins;
  27         time_t reset;
  28         time_t unlocktime;
  29         int counter;
  30         bool locked;
  31
  32         joinfloodsettings(InspIRCd *Instance, int b, int c) : ServerInstance(Instance), secs(b), joins(c)
  33         {
  34                 reset = ServerInstance->Time() + secs;
  35                 counter = 0;
  36                 locked = false;
  37         };
  38
  39         void addjoin()
  40         {
  41                 counter++;
  42                 if (ServerInstance->Time() > reset)
  43                 {
  44                         counter = 0;
  45                         reset = ServerInstance->Time() + secs;
  46                 }
  47         }
  48
  49         bool shouldlock()
  50         {
  51                 return (counter >= this->joins);
  52         }
  53
  54         void clear()
  55         {
  56                 counter = 0;
  57         }
  58
  59         bool islocked()
  60         {
  61                 if (locked)
  62                 {
  63                         if (ServerInstance->Time() > unlocktime)
  64                         {
  65                                 locked = false;
  66                                 return false;
  67                         }
  68                         else
  69                         {
  70                                 return true;
  71                         }
  72                 }
  73                 return false;
  74         }
  75
  76         void lock()
  77         {
  78                 locked = true;
  79                 unlocktime = ServerInstance->Time() + 60;
  80         }
  81
  82 };
  83
  84 /** Handles channel mode +j
  85  */
  86 class JoinFlood : public ModeHandler
  87 {
  88  public:
  89         SimpleExtItem<joinfloodsettings> ext;
  90         JoinFlood(InspIRCd* Instance, Module* Creator) : ModeHandler(Creator, 'j', PARAM_SETONLY, MODETYPE_CHANNEL),
  91                 ext("joinflood", Creator) { }
  92
  93         ModePair ModeSet(User* source, User* dest, Channel* channel, const std::string &parameter)
  94         {
  95                 joinfloodsettings* x = ext.get(channel);
  96                 if (x)
  97                         return std::make_pair(true, ConvToStr(x->joins)+":"+ConvToStr(x->secs));
  98                 else
  99                         return std::make_pair(false, parameter);
 100         }
 101
 102         ModeAction OnModeChange(User* source, User* dest, Channel* channel, std::string &parameter, bool adding)
 103         {
 104                 if (adding)
 105                 {
 106                         char ndata[MAXBUF];
 107                         char* data = ndata;
 108                         strlcpy(ndata,parameter.c_str(),MAXBUF);
 109                         char* joins = data;
 110                         char* secs = NULL;
 111                         while (*data)
 112                         {
 113                                 if (*data == ':')
 114                                 {
 115                                         *data = 0;
 116                                         data++;
 117                                         secs = data;
 118                                         break;
 119                                 }
 120                                 else data++;
 121                         }
 122                         if (secs)
 123
 124                         {
 125                                 /* Set up the flood parameters for this channel */
 126                                 int njoins = atoi(joins);
 127                                 int nsecs = atoi(secs);
 128                                 if ((njoins<1) || (nsecs<1))
 129                                 {
 130                                         source->WriteNumeric(608, "%s %s :Invalid flood parameter",source->nick.c_str(),channel->name.c_str());
 131                                         parameter.clear();
 132                                         return MODEACTION_DENY;
 133                                 }
 134                                 else
 135                                 {
 136                                         joinfloodsettings* f = ext.get(channel);
 137                                         if (!f)
 138                                         {
 139                                                 parameter = ConvToStr(njoins) + ":" +ConvToStr(nsecs);
 140                                                 f = new joinfloodsettings(ServerInstance, nsecs, njoins);
 141                                                 ext.set(channel, f);
 142                                                 channel->SetModeParam('j', parameter);
 143                                                 return MODEACTION_ALLOW;
 144                                         }
 145                                         else
 146                                         {
 147                                                 std::string cur_param = channel->GetModeParameter('j');
 148                                                 parameter = ConvToStr(njoins) + ":" +ConvToStr(nsecs);
 149                                                 if (cur_param == parameter)
 150                                                 {
 151                                                         // mode params match
 152                                                         return MODEACTION_DENY;
 153                                                 }
 154                                                 else
 155                                                 {
 156                                                         // new mode param, replace old with new
 157                                                         if ((nsecs > 0) && (njoins > 0))
 158                                                         {
 159                                                                 f = new joinfloodsettings(ServerInstance, nsecs, njoins);
 160                                                                 ext.set(channel, f);
 161                                                                 channel->SetModeParam('j', parameter);
 162                                                                 return MODEACTION_ALLOW;
 163                                                         }
 164                                                         else
 165                                                         {
 166                                                                 return MODEACTION_DENY;
 167                                                         }
 168                                                 }
 169                                         }
 170                                 }
 171                         }
 172                         else
 173                         {
 174                                 source->WriteNumeric(608, "%s %s :Invalid flood parameter",source->nick.c_str(),channel->name.c_str());
 175                                 return MODEACTION_DENY;
 176                         }
 177                 }
 178                 else
 179                 {
 180                         joinfloodsettings* f = ext.get(channel);
 181                         if (f)
 182                         {
 183                                 ext.unset(channel);
 184                                 channel->SetModeParam('j', "");
 185                                 return MODEACTION_ALLOW;
 186                         }
 187                 }
 188                 return MODEACTION_DENY;
 189         }
 190 };
 191
 192 class ModuleJoinFlood : public Module
 193 {
 194
 195         JoinFlood jf;
 196
 197  public:
 198
 199         ModuleJoinFlood(InspIRCd* Me)
 200                 : Module(Me), jf(Me, this)
 201         {
 202
 203                 if (!ServerInstance->Modes->AddMode(&jf))
 204                         throw ModuleException("Could not add new modes!");
 205                 Extensible::Register(&jf.ext);
 206                 Implementation eventlist[] = { I_OnChannelDelete, I_OnUserPreJoin, I_OnUserJoin };
 207                 ServerInstance->Modules->Attach(eventlist, this, 3);
 208         }
 209
 210         ModResult OnUserPreJoin(User* user, Channel* chan, const char* cname, std::string &privs, const std::string &keygiven)
 211         {
 212                 if (chan)
 213                 {
 214                         joinfloodsettings *f = jf.ext.get(chan);
 215                         if (f && f->islocked())
 216                         {
 217                                 user->WriteNumeric(609, "%s %s :This channel is temporarily unavailable (+j). Please try again later.",user->nick.c_str(),chan->name.c_str());
 218                                 return MOD_RES_DENY;
 219                         }
 220                 }
 221                 return MOD_RES_PASSTHRU;
 222         }
 223
 224         void OnUserJoin(Membership* memb, bool sync, bool created, CUList& excepts)
 225         {
 226                 /* We arent interested in JOIN events caused by a network burst */
 227                 if (sync)
 228                         return;
 229
 230                 joinfloodsettings *f = jf.ext.get(memb->chan);
 231
 232                 /* But all others are OK */
 233                 if (f)
 234                 {
 235                         f->addjoin();
 236                         if (f->shouldlock())
 237                         {
 238                                 f->clear();
 239                                 f->lock();
 240                                 memb->chan->WriteChannelWithServ((char*)ServerInstance->Config->ServerName, "NOTICE %s :This channel has been closed to new users for 60 seconds because there have been more than %d joins in %d seconds.", memb->chan->name.c_str(), f->joins, f->secs);
 241                         }
 242                 }
 243         }
 244
 245         ~ModuleJoinFlood()
 246         {
 247                 ServerInstance->Modes->DelMode(&jf);
 248         }
 249
 250         Version GetVersion()
 251         {
 252                 return Version("Provides channel mode +j (join flood protection)", VF_COMMON | VF_VENDOR, API_VERSION);
 253         }
 254 };
 255
 256 MODULE_INIT(ModuleJoinFlood)