src/modules/m_messageflood.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd: (C) 2002-2008 InspIRCd Development Team
   6  * See: http://www.inspircd.org/wiki/index.php/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) : ServerInstance(Instance), ban(0), secs(0), lines(0) {};
  32         floodsettings(InspIRCd *Instance, bool a, int b, int c) : ServerInstance(Instance), ban(a), secs(b), lines(c)
  33         {
  34                 reset = ServerInstance->Time() + secs;
  35         };
  36
  37         void addmessage(User* who)
  38         {
  39                 std::map<User*,int>::iterator iter = counters.find(who);
  40                 if (iter != counters.end())
  41                 {
  42                         iter->second++;
  43                 }
  44                 else
  45                 {
  46                         counters[who] = 1;
  47                 }
  48                 if (ServerInstance->Time() > reset)
  49                 {
  50                         counters.clear();
  51                         reset = ServerInstance->Time() + secs;
  52                 }
  53         }
  54
  55         bool shouldkick(User* who)
  56         {
  57                 std::map<User*,int>::iterator iter = counters.find(who);
  58                 if (iter != counters.end())
  59                 {
  60                         return (iter->second >= this->lines);
  61                 }
  62                 else return false;
  63         }
  64
  65         void clear(User* who)
  66         {
  67                 std::map<User*,int>::iterator iter = counters.find(who);
  68                 if (iter != counters.end())
  69                 {
  70                         counters.erase(iter);
  71                 }
  72         }
  73 };
  74
  75 /** Handles channel mode +f
  76  */
  77 class MsgFlood : public ModeHandler
  78 {
  79  public:
  80         MsgFlood(InspIRCd* Instance) : ModeHandler(Instance, 'f', 1, 0, false, MODETYPE_CHANNEL, false) { }
  81
  82         ModePair ModeSet(User* source, User* dest, Channel* channel, const std::string &parameter)
  83         {
  84                 floodsettings* x;
  85                 if (channel->GetExt("flood",x))
  86                         return std::make_pair(true, (x->ban ? "*" : "")+ConvToStr(x->lines)+":"+ConvToStr(x->secs));
  87                 else
  88                         return std::make_pair(false, parameter);
  89         }
  90
  91         bool CheckTimeStamp(time_t theirs, time_t ours, const std::string &their_param, const std::string &our_param, Channel* channel)
  92         {
  93                 /* When TS is equal, the alphabetically later one wins */
  94                 return (their_param < our_param);
  95         }
  96
  97         ModeAction OnModeChange(User* source, User* dest, Channel* channel, std::string &parameter, bool adding, bool)
  98         {
  99                 floodsettings *f;
 100
 101                 if (adding)
 102                 {
 103                         char ndata[MAXBUF];
 104                         char* data = ndata;
 105                         strlcpy(ndata,parameter.c_str(),MAXBUF);
 106                         char* lines = data;
 107                         char* secs = NULL;
 108                         bool ban = false;
 109                         if (*data == '*')
 110                         {
 111                                 ban = true;
 112                                 lines++;
 113                         }
 114                         else
 115                         {
 116                                 ban = false;
 117                         }
 118                         while (*data)
 119                         {
 120                                 if (*data == ':')
 121                                 {
 122                                         *data = 0;
 123                                         data++;
 124                                         secs = data;
 125                                         break;
 126                                 }
 127                                 else data++;
 128                         }
 129                         if (secs)
 130                         {
 131                                 /* Set up the flood parameters for this channel */
 132                                 int nlines = atoi(lines);
 133                                 int nsecs = atoi(secs);
 134                                 if ((nlines<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("flood", f))
 143                                         {
 144                                                 parameter = std::string(ban ? "*" : "") + ConvToStr(nlines) + ":" +ConvToStr(nsecs);
 145                                                 floodsettings *fs = new floodsettings(ServerInstance,ban,nsecs,nlines);
 146                                                 channel->Extend("flood",fs);
 147                                                 channel->SetMode('f', true);
 148                                                 channel->SetModeParam('f', parameter.c_str(), true);
 149                                                 return MODEACTION_ALLOW;
 150                                         }
 151                                         else
 152                                         {
 153                                                 std::string cur_param = channel->GetModeParameter('f');
 154                                                 parameter = std::string(ban ? "*" : "") + ConvToStr(nlines) + ":" +ConvToStr(nsecs);
 155                                                 if (cur_param == parameter)
 156                                                 {
 157                                                         // mode params match
 158                                                         return MODEACTION_DENY;
 159                                                 }
 160                                                 else
 161                                                 {
 162                                                         if ((((nlines != f->lines) || (nsecs != f->secs) || (ban != f->ban))) && (((nsecs > 0) && (nlines > 0))))
 163                                                         {
 164                                                                 delete f;
 165                                                                 floodsettings *fs = new floodsettings(ServerInstance,ban,nsecs,nlines);
 166                                                                 channel->Shrink("flood");
 167                                                                 channel->Extend("flood",fs);
 168                                                                 channel->SetModeParam('f', cur_param.c_str(), false);
 169                                                                 channel->SetModeParam('f', parameter.c_str(), true);
 170                                                                 return MODEACTION_ALLOW;
 171                                                         }
 172                                                         else
 173                                                         {
 174                                                                 return MODEACTION_DENY;
 175                                                         }
 176                                                 }
 177                                         }
 178                                 }
 179                         }
 180                         else
 181                         {
 182                                 source->WriteNumeric(608, "%s %s :Invalid flood parameter",source->nick.c_str(),channel->name.c_str());
 183                                 parameter.clear();
 184                                 return MODEACTION_DENY;
 185                         }
 186                 }
 187                 else
 188                 {
 189                         if (channel->GetExt("flood", f))
 190                         {
 191                                 delete f;
 192                                 channel->Shrink("flood");
 193                                 channel->SetMode('f', false);
 194                                 return MODEACTION_ALLOW;
 195                         }
 196                 }
 197
 198                 return MODEACTION_DENY;
 199         }
 200 };
 201
 202 class ModuleMsgFlood : public Module
 203 {
 204
 205         MsgFlood* mf;
 206
 207  public:
 208
 209         ModuleMsgFlood(InspIRCd* Me)
 210                 : Module(Me)
 211         {
 212
 213                 mf = new MsgFlood(ServerInstance);
 214                 if (!ServerInstance->Modes->AddMode(mf))
 215                         throw ModuleException("Could not add new modes!");
 216                 Implementation eventlist[] = { I_OnChannelDelete, I_OnUserPreNotice, I_OnUserPreMessage };
 217                 ServerInstance->Modules->Attach(eventlist, this, 3);
 218         }
 219
 220         int ProcessMessages(User* user,Channel* dest, const std::string &text)
 221         {
 222                 if (!IS_LOCAL(user) || (CHANOPS_EXEMPT(ServerInstance, 'f') && dest->GetStatus(user) == STATUS_OP))
 223                 {
 224                         return 0;
 225                 }
 226
 227                 floodsettings *f;
 228                 if (dest->GetExt("flood", f))
 229                 {
 230                         f->addmessage(user);
 231                         if (f->shouldkick(user))
 232                         {
 233                                 /* Youre outttta here! */
 234                                 f->clear(user);
 235                                 if (f->ban)
 236                                 {
 237                                         std::vector<std::string> parameters;
 238                                         parameters.push_back(dest->name);
 239                                         parameters.push_back("+b");
 240                                         parameters.push_back(user->MakeWildHost());
 241                                         ServerInstance->SendMode(parameters, ServerInstance->FakeClient);
 242
 243                                         ServerInstance->PI->SendModeStr(dest->name, std::string("+b ") + user->MakeWildHost());
 244                                 }
 245
 246                                 char kickmessage[MAXBUF];
 247                                 snprintf(kickmessage, MAXBUF, "Channel flood triggered (limit is %d lines in %d secs)", f->lines, f->secs);
 248
 249                                 if (!dest->ServerKickUser(user, kickmessage, true))
 250                                 {
 251                                         delete dest;
 252                                 }
 253
 254                                 return 1;
 255                         }
 256                 }
 257
 258                 return 0;
 259         }
 260
 261         virtual int OnUserPreMessage(User *user, void *dest, int target_type, std::string &text, char status, CUList &exempt_list)
 262         {
 263                 if (target_type == TYPE_CHANNEL)
 264                         return ProcessMessages(user,(Channel*)dest,text);
 265
 266                 return 0;
 267         }
 268
 269         virtual int OnUserPreNotice(User *user, void *dest, int target_type, std::string &text, char status, CUList &exempt_list)
 270         {
 271                 if (target_type == TYPE_CHANNEL)
 272                         return ProcessMessages(user,(Channel*)dest,text);
 273
 274                 return 0;
 275         }
 276
 277         void OnChannelDelete(Channel* chan)
 278         {
 279                 floodsettings* f;
 280                 if (chan->GetExt("flood", f))
 281                 {
 282                         delete f;
 283                         chan->Shrink("flood");
 284                 }
 285         }
 286
 287
 288         virtual ~ModuleMsgFlood()
 289         {
 290                 ServerInstance->Modes->DelMode(mf);
 291                 delete mf;
 292         }
 293
 294         virtual Version GetVersion()
 295         {
 296                 return Version("$Id$", VF_COMMON | VF_VENDOR, API_VERSION);
 297         }
 298 };
 299
 300 MODULE_INIT(ModuleMsgFlood)