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(InspIRCd *Instance, bool a, int b, int c) : ServerInstance(Instance), 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         MsgFlood(InspIRCd* Instance) : ModeHandler(Instance, 'f', 1, 0, false, MODETYPE_CHANNEL, false) { }
  80
  81         ModePair ModeSet(User* source, User* dest, Channel* channel, const std::string &parameter)
  82         {
  83                 floodsettings* x;
  84                 if (channel->GetExt("flood",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         bool CheckTimeStamp(time_t theirs, time_t ours, const std::string &their_param, const std::string &our_param, Channel* channel)
  91         {
  92                 /* When TS is equal, the alphabetically later one wins */
  93                 return (their_param < our_param);
  94         }
  95
  96         ModeAction OnModeChange(User* source, User* dest, Channel* channel, std::string &parameter, bool adding, bool)
  97         {
  98                 floodsettings *f;
  99
 100                 if (adding)
 101                 {
 102                         char ndata[MAXBUF];
 103                         char* data = ndata;
 104                         strlcpy(ndata,parameter.c_str(),MAXBUF);
 105                         char* lines = data;
 106                         char* secs = NULL;
 107                         bool ban = false;
 108                         if (*data == '*')
 109                         {
 110                                 ban = true;
 111                                 lines++;
 112                         }
 113                         else
 114                         {
 115                                 ban = false;
 116                         }
 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                                 /* Set up the flood parameters for this channel */
 131                                 int nlines = atoi(lines);
 132                                 int nsecs = atoi(secs);
 133                                 if ((nlines<2) || (nsecs<1))
 134                                 {
 135                                         source->WriteNumeric(608, "%s %s :Invalid flood parameter",source->nick.c_str(),channel->name.c_str());
 136                                         parameter.clear();
 137                                         return MODEACTION_DENY;
 138                                 }
 139                                 else
 140                                 {
 141                                         if (!channel->GetExt("flood", f))
 142                                         {
 143                                                 parameter = std::string(ban ? "*" : "") + ConvToStr(nlines) + ":" +ConvToStr(nsecs);
 144                                                 floodsettings *fs = new floodsettings(ServerInstance,ban,nsecs,nlines);
 145                                                 channel->Extend("flood",fs);
 146                                                 channel->SetModeParam('f', parameter);
 147                                                 return MODEACTION_ALLOW;
 148                                         }
 149                                         else
 150                                         {
 151                                                 std::string cur_param = channel->GetModeParameter('f');
 152                                                 parameter = std::string(ban ? "*" : "") + ConvToStr(nlines) + ":" +ConvToStr(nsecs);
 153                                                 if (cur_param == parameter)
 154                                                 {
 155                                                         // mode params match
 156                                                         return MODEACTION_DENY;
 157                                                 }
 158                                                 else
 159                                                 {
 160                                                         if ((((nlines != f->lines) || (nsecs != f->secs) || (ban != f->ban))) && (((nsecs > 0) && (nlines > 0))))
 161                                                         {
 162                                                                 delete f;
 163                                                                 floodsettings *fs = new floodsettings(ServerInstance,ban,nsecs,nlines);
 164                                                                 channel->Shrink("flood");
 165                                                                 channel->Extend("flood",fs);
 166                                                                 channel->SetModeParam('f', parameter);
 167                                                                 return MODEACTION_ALLOW;
 168                                                         }
 169                                                         else
 170                                                         {
 171                                                                 return MODEACTION_DENY;
 172                                                         }
 173                                                 }
 174                                         }
 175                                 }
 176                         }
 177                         else
 178                         {
 179                                 source->WriteNumeric(608, "%s %s :Invalid flood parameter",source->nick.c_str(),channel->name.c_str());
 180                                 parameter.clear();
 181                                 return MODEACTION_DENY;
 182                         }
 183                 }
 184                 else
 185                 {
 186                         if (channel->GetExt("flood", f))
 187                         {
 188                                 delete f;
 189                                 channel->Shrink("flood");
 190                                 channel->SetModeParam('f', "");
 191                                 return MODEACTION_ALLOW;
 192                         }
 193                 }
 194
 195                 return MODEACTION_DENY;
 196         }
 197 };
 198
 199 class ModuleMsgFlood : public Module
 200 {
 201         MsgFlood mf;
 202
 203  public:
 204
 205         ModuleMsgFlood(InspIRCd* Me)
 206                 : Module(Me), mf(Me)
 207         {
 208                 if (!ServerInstance->Modes->AddMode(&mf))
 209                         throw ModuleException("Could not add new modes!");
 210                 Implementation eventlist[] = { I_OnChannelDelete, I_OnUserPreNotice, I_OnUserPreMessage };
 211                 ServerInstance->Modules->Attach(eventlist, this, 3);
 212         }
 213
 214         int ProcessMessages(User* user,Channel* dest, const std::string &text)
 215         {
 216                 if (!IS_LOCAL(user) || (CHANOPS_EXEMPT(ServerInstance, 'f') && dest->GetStatus(user) == STATUS_OP))
 217                 {
 218                         return 0;
 219                 }
 220
 221                 floodsettings *f;
 222                 if (dest->GetExt("flood", f))
 223                 {
 224                         f->addmessage(user);
 225                         if (f->shouldkick(user))
 226                         {
 227                                 /* Youre outttta here! */
 228                                 f->clear(user);
 229                                 if (f->ban)
 230                                 {
 231                                         std::vector<std::string> parameters;
 232                                         parameters.push_back(dest->name);
 233                                         parameters.push_back("+b");
 234                                         parameters.push_back(user->MakeWildHost());
 235                                         ServerInstance->SendMode(parameters, ServerInstance->FakeClient);
 236
 237                                         ServerInstance->PI->SendModeStr(dest->name, std::string("+b ") + user->MakeWildHost());
 238                                 }
 239
 240                                 char kickmessage[MAXBUF];
 241                                 snprintf(kickmessage, MAXBUF, "Channel flood triggered (limit is %d lines in %d secs)", f->lines, f->secs);
 242
 243                                 if (!dest->ServerKickUser(user, kickmessage))
 244                                 {
 245                                         delete dest;
 246                                 }
 247
 248                                 return 1;
 249                         }
 250                 }
 251
 252                 return 0;
 253         }
 254
 255         virtual int OnUserPreMessage(User *user, void *dest, int target_type, std::string &text, char status, CUList &exempt_list)
 256         {
 257                 if (target_type == TYPE_CHANNEL)
 258                         return ProcessMessages(user,(Channel*)dest,text);
 259
 260                 return 0;
 261         }
 262
 263         virtual int OnUserPreNotice(User *user, void *dest, int target_type, std::string &text, char status, CUList &exempt_list)
 264         {
 265                 if (target_type == TYPE_CHANNEL)
 266                         return ProcessMessages(user,(Channel*)dest,text);
 267
 268                 return 0;
 269         }
 270
 271         void OnChannelDelete(Channel* chan)
 272         {
 273                 floodsettings* f;
 274                 if (chan->GetExt("flood", f))
 275                 {
 276                         delete f;
 277                         chan->Shrink("flood");
 278                 }
 279         }
 280
 281
 282         virtual ~ModuleMsgFlood()
 283         {
 284                 ServerInstance->Modes->DelMode(&mf);
 285         }
 286
 287         virtual Version GetVersion()
 288         {
 289                 return Version("$Id$", VF_COMMON | VF_VENDOR, API_VERSION);
 290         }
 291 };
 292
 293 MODULE_INIT(ModuleMsgFlood)