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