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         JoinFlood(InspIRCd* Instance) : ModeHandler(Instance, 'j', 1, 0, false, MODETYPE_CHANNEL, false) { }
  90
  91         ModePair ModeSet(User* source, User* dest, Channel* channel, const std::string &parameter)
  92         {
  93                 joinfloodsettings* x;
  94                 if (channel->GetExt("joinflood",x))
  95                         return std::make_pair(true, ConvToStr(x->joins)+":"+ConvToStr(x->secs));
  96                 else
  97                         return std::make_pair(false, parameter);
  98         }
  99
 100         bool CheckTimeStamp(time_t theirs, time_t ours, const std::string &their_param, const std::string &our_param, Channel* channel)
 101         {
 102                 /* When TS is equal, the alphabetically later one wins */
 103                 return (their_param < our_param);
 104         }
 105
 106         ModeAction OnModeChange(User* source, User* dest, Channel* channel, std::string &parameter, bool adding, bool)
 107         {
 108                 joinfloodsettings* dummy;
 109
 110                 if (adding)
 111                 {
 112                         char ndata[MAXBUF];
 113                         char* data = ndata;
 114                         strlcpy(ndata,parameter.c_str(),MAXBUF);
 115                         char* joins = data;
 116                         char* secs = NULL;
 117                         while (*data)
 118                         {
 119                                 if (*data == ':')
 120                                 {
 121                                         *data = 0;
 122                                         data++;
 123                                         secs = data;
 124                                         break;
 125                                 }
 126                                 else data++;
 127                         }
 128                         if (secs)
 129
 130                         {
 131                                 /* Set up the flood parameters for this channel */
 132                                 int njoins = atoi(joins);
 133                                 int nsecs = atoi(secs);
 134                                 if ((njoins<1) || (nsecs<1))
 135                                 {
 136                                         source->WriteNumeric(608, "%s %s :Invalid flood parameter",source->nick.c_str(),channel->name.c_str());
 137                                         parameter.clear();
 138                                         return MODEACTION_DENY;
 139                                 }
 140                                 else
 141                                 {
 142                                         if (!channel->GetExt("joinflood", dummy))
 143                                         {
 144                                                 parameter = ConvToStr(njoins) + ":" +ConvToStr(nsecs);
 145                                                 joinfloodsettings *f = new joinfloodsettings(ServerInstance, nsecs, njoins);
 146                                                 channel->Extend("joinflood", f);
 147                                                 channel->SetModeParam('j', parameter);
 148                                                 return MODEACTION_ALLOW;
 149                                         }
 150                                         else
 151                                         {
 152                                                 std::string cur_param = channel->GetModeParameter('j');
 153                                                 parameter = ConvToStr(njoins) + ":" +ConvToStr(nsecs);
 154                                                 if (cur_param == parameter)
 155                                                 {
 156                                                         // mode params match
 157                                                         return MODEACTION_DENY;
 158                                                 }
 159                                                 else
 160                                                 {
 161                                                         // new mode param, replace old with new
 162                                                         if ((nsecs > 0) && (njoins > 0))
 163                                                         {
 164                                                                 joinfloodsettings* f;
 165                                                                 channel->GetExt("joinflood", f);
 166                                                                 delete f;
 167                                                                 f = new joinfloodsettings(ServerInstance, nsecs, njoins);
 168                                                                 channel->Shrink("joinflood");
 169                                                                 channel->Extend("joinflood", f);
 170                                                                 channel->SetModeParam('j', parameter);
 171                                                                 return MODEACTION_ALLOW;
 172                                                         }
 173                                                         else
 174                                                         {
 175                                                                 return MODEACTION_DENY;
 176                                                         }
 177                                                 }
 178                                         }
 179                                 }
 180                         }
 181                         else
 182                         {
 183                                 source->WriteNumeric(608, "%s %s :Invalid flood parameter",source->nick.c_str(),channel->name.c_str());
 184                                 return MODEACTION_DENY;
 185                         }
 186                 }
 187                 else
 188                 {
 189                         if (channel->GetExt("joinflood", dummy))
 190                         {
 191                                 joinfloodsettings *f;
 192                                 channel->GetExt("joinflood", f);
 193                                 delete f;
 194                                 channel->Shrink("joinflood");
 195                                 channel->SetModeParam('j', "");
 196                                 return MODEACTION_ALLOW;
 197                         }
 198                 }
 199                 return MODEACTION_DENY;
 200         }
 201 };
 202
 203 class ModuleJoinFlood : public Module
 204 {
 205
 206         JoinFlood jf;
 207
 208  public:
 209
 210         ModuleJoinFlood(InspIRCd* Me)
 211                 : Module(Me), jf(Me)
 212         {
 213
 214                 if (!ServerInstance->Modes->AddMode(&jf))
 215                         throw ModuleException("Could not add new modes!");
 216                 Implementation eventlist[] = { I_OnChannelDelete, I_OnUserPreJoin, I_OnUserJoin };
 217                 ServerInstance->Modules->Attach(eventlist, this, 3);
 218         }
 219
 220         virtual int OnUserPreJoin(User* user, Channel* chan, const char* cname, std::string &privs, const std::string &keygiven)
 221         {
 222                 if (chan)
 223                 {
 224                         joinfloodsettings *f;
 225                         if (chan->GetExt("joinflood", f))
 226                         {
 227                                 if (f->islocked())
 228                                 {
 229                                         user->WriteNumeric(609, "%s %s :This channel is temporarily unavailable (+j). Please try again later.",user->nick.c_str(),chan->name.c_str());
 230                                         return 1;
 231                                 }
 232                         }
 233                 }
 234                 return 0;
 235         }
 236
 237         virtual void OnUserJoin(User* user, Channel* channel, bool sync, bool &silent)
 238         {
 239                 joinfloodsettings *f;
 240
 241                 /* We arent interested in JOIN events caused by a network burst */
 242                 if (sync)
 243                         return;
 244
 245                 /* But all others are OK */
 246                 if (channel->GetExt("joinflood",f))
 247                 {
 248                         f->addjoin();
 249                         if (f->shouldlock())
 250                         {
 251                                 f->clear();
 252                                 f->lock();
 253                                 channel->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.", channel->name.c_str(), f->joins, f->secs);
 254                         }
 255                 }
 256         }
 257
 258         void OnChannelDelete(Channel* chan)
 259         {
 260                 joinfloodsettings *f;
 261                 if (chan->GetExt("joinflood",f))
 262                 {
 263                         delete f;
 264                         chan->Shrink("joinflood");
 265                 }
 266         }
 267
 268
 269         virtual ~ModuleJoinFlood()
 270         {
 271                 ServerInstance->Modes->DelMode(&jf);
 272         }
 273
 274         virtual Version GetVersion()
 275         {
 276                 return Version("$Id$", VF_COMMON | VF_VENDOR, API_VERSION);
 277         }
 278 };
 279
 280 MODULE_INIT(ModuleJoinFlood)