src/modules/m_messageflood.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd: (C) 2002-2010 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         ModeAction OnModeChange(User* source, User* dest, Channel* channel, std::string &parameter, bool adding)
  82         {
  83                 floodsettings *f = ext.get(channel);
  84
  85                 if (adding)
  86                 {
  87                         char ndata[MAXBUF];
  88                         char* data = ndata;
  89                         strlcpy(ndata,parameter.c_str(),MAXBUF);
  90                         char* lines = data;
  91                         char* secs = NULL;
  92                         bool ban = false;
  93                         if (*data == '*')
  94                         {
  95                                 ban = true;
  96                                 lines++;
  97                         }
  98                         else
  99                         {
 100                                 ban = false;
 101                         }
 102                         while (*data)
 103                         {
 104                                 if (*data == ':')
 105                                 {
 106                                         *data = 0;
 107                                         data++;
 108                                         secs = data;
 109                                         break;
 110                                 }
 111                                 else data++;
 112                         }
 113                         if (secs)
 114                         {
 115                                 /* Set up the flood parameters for this channel */
 116                                 int nlines = atoi(lines);
 117                                 int nsecs = atoi(secs);
 118                                 if ((nlines<2) || (nsecs<1))
 119                                 {
 120                                         source->WriteNumeric(608, "%s %s :Invalid flood parameter",source->nick.c_str(),channel->name.c_str());
 121                                         parameter.clear();
 122                                         return MODEACTION_DENY;
 123                                 }
 124                                 else
 125                                 {
 126                                         if (!f)
 127                                         {
 128                                                 parameter = std::string(ban ? "*" : "") + ConvToStr(nlines) + ":" +ConvToStr(nsecs);
 129                                                 f = new floodsettings(ban,nsecs,nlines);
 130                                                 ext.set(channel, f);
 131                                                 channel->SetModeParam('f', parameter);
 132                                                 return MODEACTION_ALLOW;
 133                                         }
 134                                         else
 135                                         {
 136                                                 std::string cur_param = channel->GetModeParameter('f');
 137                                                 parameter = std::string(ban ? "*" : "") + ConvToStr(nlines) + ":" +ConvToStr(nsecs);
 138                                                 if (cur_param == parameter)
 139                                                 {
 140                                                         // mode params match
 141                                                         return MODEACTION_DENY;
 142                                                 }
 143                                                 else
 144                                                 {
 145                                                         if ((((nlines != f->lines) || (nsecs != f->secs) || (ban != f->ban))) && (((nsecs > 0) && (nlines > 0))))
 146                                                         {
 147                                                                 floodsettings *fs = new floodsettings(ban,nsecs,nlines);
 148                                                                 ext.set(channel, fs);
 149                                                                 channel->SetModeParam('f', parameter);
 150                                                                 return MODEACTION_ALLOW;
 151                                                         }
 152                                                         else
 153                                                         {
 154                                                                 return MODEACTION_DENY;
 155                                                         }
 156                                                 }
 157                                         }
 158                                 }
 159                         }
 160                         else
 161                         {
 162                                 source->WriteNumeric(608, "%s %s :Invalid flood parameter",source->nick.c_str(),channel->name.c_str());
 163                                 parameter.clear();
 164                                 return MODEACTION_DENY;
 165                         }
 166                 }
 167                 else
 168                 {
 169                         if (f)
 170                         {
 171                                 ext.unset(channel);
 172                                 channel->SetModeParam('f', "");
 173                                 return MODEACTION_ALLOW;
 174                         }
 175                 }
 176
 177                 return MODEACTION_DENY;
 178         }
 179 };
 180
 181 class ModuleMsgFlood : public Module
 182 {
 183         MsgFlood mf;
 184
 185  public:
 186
 187         ModuleMsgFlood()
 188                 : mf(this)
 189         {
 190                 if (!ServerInstance->Modes->AddMode(&mf))
 191                         throw ModuleException("Could not add new modes!");
 192                 ServerInstance->Extensions.Register(&mf.ext);
 193                 Implementation eventlist[] = { I_OnUserPreNotice, I_OnUserPreMessage };
 194                 ServerInstance->Modules->Attach(eventlist, this, 2);
 195         }
 196
 197         ModResult ProcessMessages(User* user,Channel* dest, const std::string &text)
 198         {
 199                 ModResult res = ServerInstance->OnCheckExemption(user,dest,"flood");
 200                 if (!IS_LOCAL(user) || res == MOD_RES_ALLOW)
 201                         return MOD_RES_PASSTHRU;
 202
 203                 floodsettings *f = mf.ext.get(dest);
 204                 if (f)
 205                 {
 206                         f->addmessage(user);
 207                         if (f->shouldkick(user))
 208                         {
 209                                 /* Youre outttta here! */
 210                                 f->clear(user);
 211                                 if (f->ban)
 212                                 {
 213                                         std::vector<std::string> parameters;
 214                                         parameters.push_back(dest->name);
 215                                         parameters.push_back("+b");
 216                                         parameters.push_back(user->MakeWildHost());
 217                                         ServerInstance->SendGlobalMode(parameters, ServerInstance->FakeClient);
 218                                 }
 219
 220                                 char kickmessage[MAXBUF];
 221                                 snprintf(kickmessage, MAXBUF, "Channel flood triggered (limit is %d lines in %d secs)", f->lines, f->secs);
 222
 223                                 dest->KickUser(ServerInstance->FakeClient, user, kickmessage);
 224
 225                                 return MOD_RES_DENY;
 226                         }
 227                 }
 228
 229                 return MOD_RES_PASSTHRU;
 230         }
 231
 232         ModResult OnUserPreMessage(User *user, void *dest, int target_type, std::string &text, char status, CUList &exempt_list)
 233         {
 234                 if (target_type == TYPE_CHANNEL)
 235                         return ProcessMessages(user,(Channel*)dest,text);
 236
 237                 return MOD_RES_PASSTHRU;
 238         }
 239
 240         ModResult OnUserPreNotice(User *user, void *dest, int target_type, std::string &text, char status, CUList &exempt_list)
 241         {
 242                 if (target_type == TYPE_CHANNEL)
 243                         return ProcessMessages(user,(Channel*)dest,text);
 244
 245                 return MOD_RES_PASSTHRU;
 246         }
 247
 248         ~ModuleMsgFlood()
 249         {
 250         }
 251
 252         Version GetVersion()
 253         {
 254                 return Version("Provides channel mode +f (message flood protection)", VF_VENDOR);
 255         }
 256 };
 257
 258 MODULE_INIT(ModuleMsgFlood)