src/modules/m_messageflood.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 +f (message flood protection) */
  17
  18 /** Holds flood settings and state for mode +f
  19  */
  20 class floodsettings : public classbase
  21 {
  22  private:
  23         InspIRCd *ServerInstance;
  24  public:
  25         bool ban;
  26         int secs;
  27         int lines;
  28         time_t reset;
  29         std::map<User*,int> counters;
  30
  31         floodsettings(bool a, int b, int c) : ban(a), secs(b), lines(c)
  32         {
  33                 reset = ServerInstance->Time() + secs;
  34         };
  35
  36         void addmessage(User* who)
  37         {
  38                 std::map<User*,int>::iterator iter = counters.find(who);
  39                 if (iter != counters.end())
  40                 {
  41                         iter->second++;
  42                 }
  43                 else
  44                 {
  45                         counters[who] = 1;
  46                 }
  47                 if (ServerInstance->Time() > reset)
  48                 {
  49                         counters.clear();
  50                         reset = ServerInstance->Time() + secs;
  51                 }
  52         }
  53
  54         bool shouldkick(User* who)
  55         {
  56                 std::map<User*,int>::iterator iter = counters.find(who);
  57                 if (iter != counters.end())
  58                 {
  59                         return (iter->second >= this->lines);
  60                 }
  61                 else return false;
  62         }
  63
  64         void clear(User* who)
  65         {
  66                 std::map<User*,int>::iterator iter = counters.find(who);
  67                 if (iter != counters.end())
  68                 {
  69                         counters.erase(iter);
  70                 }
  71         }
  72 };
  73
  74 /** Handles channel mode +f
  75  */
  76 class MsgFlood : public ModeHandler
  77 {
  78  public:
  79         SimpleExtItem<floodsettings> ext;
  80         MsgFlood(Module* Creator) : ModeHandler(Creator, "flood", 'f', PARAM_SETONLY, MODETYPE_CHANNEL),
  81                 ext("messageflood", Creator) { }
  82
  83         ModePair ModeSet(User* source, User* dest, Channel* channel, const std::string &parameter)
  84         {
  85                 floodsettings* x = ext.get(channel);
  86                 if (x)
  87                         return std::make_pair(true, (x->ban ? "*" : "")+ConvToStr(x->lines)+":"+ConvToStr(x->secs));
  88                 else
  89                         return std::make_pair(false, parameter);
  90         }
  91
  92         ModeAction OnModeChange(User* source, User* dest, Channel* channel, std::string &parameter, bool adding)
  93         {
  94                 floodsettings *f = ext.get(channel);
  95
  96                 if (adding)
  97                 {
  98                         char ndata[MAXBUF];
  99                         char* data = ndata;
 100                         strlcpy(ndata,parameter.c_str(),MAXBUF);
 101                         char* lines = data;
 102                         char* secs = NULL;
 103                         bool ban = false;
 104                         if (*data == '*')
 105                         {
 106                                 ban = true;
 107                                 lines++;
 108                         }
 109                         else
 110                         {
 111                                 ban = false;
 112                         }
 113                         while (*data)
 114                         {
 115                                 if (*data == ':')
 116                                 {
 117                                         *data = 0;
 118                                         data++;
 119                                         secs = data;
 120                                         break;
 121                                 }
 122                                 else data++;
 123                         }
 124                         if (secs)
 125                         {
 126                                 /* Set up the flood parameters for this channel */
 127                                 int nlines = atoi(lines);
 128                                 int nsecs = atoi(secs);
 129                                 if ((nlines<2) || (nsecs<1))
 130                                 {
 131                                         source->WriteNumeric(608, "%s %s :Invalid flood parameter",source->nick.c_str(),channel->name.c_str());
 132                                         parameter.clear();
 133                                         return MODEACTION_DENY;
 134                                 }
 135                                 else
 136                                 {
 137                                         if (!f)
 138                                         {
 139                                                 parameter = std::string(ban ? "*" : "") + ConvToStr(nlines) + ":" +ConvToStr(nsecs);
 140                                                 f = new floodsettings(ban,nsecs,nlines);
 141                                                 ext.set(channel, f);
 142                                                 channel->SetModeParam('f', parameter);
 143                                                 return MODEACTION_ALLOW;
 144                                         }
 145                                         else
 146                                         {
 147                                                 std::string cur_param = channel->GetModeParameter('f');
 148                                                 parameter = std::string(ban ? "*" : "") + ConvToStr(nlines) + ":" +ConvToStr(nsecs);
 149                                                 if (cur_param == parameter)
 150                                                 {
 151                                                         // mode params match
 152                                                         return MODEACTION_DENY;
 153                                                 }
 154                                                 else
 155                                                 {
 156                                                         if ((((nlines != f->lines) || (nsecs != f->secs) || (ban != f->ban))) && (((nsecs > 0) && (nlines > 0))))
 157                                                         {
 158                                                                 floodsettings *fs = new floodsettings(ban,nsecs,nlines);
 159                                                                 ext.set(channel, fs);
 160                                                                 channel->SetModeParam('f', parameter);
 161                                                                 return MODEACTION_ALLOW;
 162                                                         }
 163                                                         else
 164                                                         {
 165                                                                 return MODEACTION_DENY;
 166                                                         }
 167                                                 }
 168                                         }
 169                                 }
 170                         }
 171                         else
 172                         {
 173                                 source->WriteNumeric(608, "%s %s :Invalid flood parameter",source->nick.c_str(),channel->name.c_str());
 174                                 parameter.clear();
 175                                 return MODEACTION_DENY;
 176                         }
 177                 }
 178                 else
 179                 {
 180                         if (f)
 181                         {
 182                                 ext.unset(channel);
 183                                 channel->SetModeParam('f', "");
 184                                 return MODEACTION_ALLOW;
 185                         }
 186                 }
 187
 188                 return MODEACTION_DENY;
 189         }
 190 };
 191
 192 class ModuleMsgFlood : public Module
 193 {
 194         MsgFlood mf;
 195
 196  public:
 197
 198         ModuleMsgFlood()
 199                 : mf(this)
 200         {
 201                 if (!ServerInstance->Modes->AddMode(&mf))
 202                         throw ModuleException("Could not add new modes!");
 203                 Extensible::Register(&mf.ext);
 204                 Implementation eventlist[] = { I_OnUserPreNotice, I_OnUserPreMessage };
 205                 ServerInstance->Modules->Attach(eventlist, this, 2);
 206         }
 207
 208         ModResult ProcessMessages(User* user,Channel* dest, const std::string &text)
 209         {
 210                 ModResult res;
 211                 FIRST_MOD_RESULT(OnChannelRestrictionApply, res, (user,dest,"flood"));
 212                 if (!IS_LOCAL(user) || res == MOD_RES_ALLOW)
 213                         return MOD_RES_PASSTHRU;
 214
 215                 floodsettings *f = mf.ext.get(dest);
 216                 if (f)
 217                 {
 218                         f->addmessage(user);
 219                         if (f->shouldkick(user))
 220                         {
 221                                 /* Youre outttta here! */
 222                                 f->clear(user);
 223                                 if (f->ban)
 224                                 {
 225                                         std::vector<std::string> parameters;
 226                                         parameters.push_back(dest->name);
 227                                         parameters.push_back("+b");
 228                                         parameters.push_back(user->MakeWildHost());
 229                                         ServerInstance->SendMode(parameters, ServerInstance->FakeClient);
 230
 231                                         ServerInstance->PI->SendModeStr(dest->name, std::string("+b ") + user->MakeWildHost());
 232                                 }
 233
 234                                 char kickmessage[MAXBUF];
 235                                 snprintf(kickmessage, MAXBUF, "Channel flood triggered (limit is %d lines in %d secs)", f->lines, f->secs);
 236
 237                                 if (!dest->ServerKickUser(user, kickmessage))
 238                                 {
 239                                         delete dest;
 240                                 }
 241
 242                                 return MOD_RES_DENY;
 243                         }
 244                 }
 245
 246                 return MOD_RES_PASSTHRU;
 247         }
 248
 249         ModResult OnUserPreMessage(User *user, void *dest, int target_type, std::string &text, char status, CUList &exempt_list)
 250         {
 251                 if (target_type == TYPE_CHANNEL)
 252                         return ProcessMessages(user,(Channel*)dest,text);
 253
 254                 return MOD_RES_PASSTHRU;
 255         }
 256
 257         ModResult OnUserPreNotice(User *user, void *dest, int target_type, std::string &text, char status, CUList &exempt_list)
 258         {
 259                 if (target_type == TYPE_CHANNEL)
 260                         return ProcessMessages(user,(Channel*)dest,text);
 261
 262                 return MOD_RES_PASSTHRU;
 263         }
 264
 265         ~ModuleMsgFlood()
 266         {
 267         }
 268
 269         Version GetVersion()
 270         {
 271                 return Version("Provides channel mode +f (message flood protection)", VF_COMMON | VF_VENDOR, API_VERSION);
 272         }
 273 };
 274
 275 MODULE_INIT(ModuleMsgFlood)