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  public:
  23         bool ban;
  24         int secs;
  25         int lines;
  26         time_t reset;
  27         std::map<User*,int> counters;
  28
  29         floodsettings() : ban(0), secs(0), lines(0) {};
  30         floodsettings(bool a, int b, int c) : ban(a), secs(b), lines(c)
  31         {
  32                 reset = time(NULL) + secs;
  33         };
  34
  35         void addmessage(User* who)
  36         {
  37                 std::map<User*,int>::iterator iter = counters.find(who);
  38                 if (iter != counters.end())
  39                 {
  40                         iter->second++;
  41                 }
  42                 else
  43                 {
  44                         counters[who] = 1;
  45                 }
  46                 if (time(NULL) > reset)
  47                 {
  48                         counters.clear();
  49                         reset = time(NULL) + secs;
  50                 }
  51         }
  52
  53         bool shouldkick(User* who)
  54         {
  55                 std::map<User*,int>::iterator iter = counters.find(who);
  56                 if (iter != counters.end())
  57                 {
  58                         return (iter->second >= this->lines);
  59                 }
  60                 else return false;
  61         }
  62
  63         void clear(User* who)
  64         {
  65                 std::map<User*,int>::iterator iter = counters.find(who);
  66                 if (iter != counters.end())
  67                 {
  68                         counters.erase(iter);
  69                 }
  70         }
  71 };
  72
  73 /** Handles channel mode +f
  74  */
  75 class MsgFlood : public ModeHandler
  76 {
  77  public:
  78         MsgFlood(InspIRCd* Instance) : ModeHandler(Instance, 'f', 1, 0, false, MODETYPE_CHANNEL, false) { }
  79
  80         ModePair ModeSet(User* source, User* dest, Channel* channel, const std::string &parameter)
  81         {
  82                 floodsettings* x;
  83                 if (channel->GetExt("flood",x))
  84                         return std::make_pair(true, (x->ban ? "*" : "")+ConvToStr(x->lines)+":"+ConvToStr(x->secs));
  85                 else
  86                         return std::make_pair(false, parameter);
  87         }
  88
  89         bool CheckTimeStamp(time_t theirs, time_t ours, const std::string &their_param, const std::string &our_param, Channel* channel)
  90         {
  91                 /* When TS is equal, the alphabetically later one wins */
  92                 return (their_param < our_param);
  93         }
  94
  95         ModeAction OnModeChange(User* source, User* dest, Channel* channel, std::string &parameter, bool adding, bool)
  96         {
  97                 floodsettings *f;
  98
  99                 if (adding)
 100                 {
 101                         char ndata[MAXBUF];
 102                         char* data = ndata;
 103                         strlcpy(ndata,parameter.c_str(),MAXBUF);
 104                         char* lines = data;
 105                         char* secs = NULL;
 106                         bool ban = false;
 107                         if (*data == '*')
 108                         {
 109                                 ban = true;
 110                                 lines++;
 111                         }
 112                         else
 113                         {
 114                                 ban = false;
 115                         }
 116                         while (*data)
 117                         {
 118                                 if (*data == ':')
 119                                 {
 120                                         *data = 0;
 121                                         data++;
 122                                         secs = data;
 123                                         break;
 124                                 }
 125                                 else data++;
 126                         }
 127                         if (secs)
 128                         {
 129                                 /* Set up the flood parameters for this channel */
 130                                 int nlines = atoi(lines);
 131                                 int nsecs = atoi(secs);
 132                                 if ((nlines<1) || (nsecs<1))
 133                                 {
 134                                         source->WriteNumeric(608, "%s %s :Invalid flood parameter",source->nick,channel->name);
 135                                         parameter.clear();
 136                                         return MODEACTION_DENY;
 137                                 }
 138                                 else
 139                                 {
 140                                         if (!channel->GetExt("flood", f))
 141                                         {
 142                                                 parameter = std::string(ban ? "*" : "") + ConvToStr(nlines) + ":" +ConvToStr(nsecs);
 143                                                 floodsettings *fs = new floodsettings(ban,nsecs,nlines);
 144                                                 channel->Extend("flood",fs);
 145                                                 channel->SetMode('f', true);
 146                                                 channel->SetModeParam('f', parameter.c_str(), true);
 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)) && ((nsecs > 0) && (nlines > 0)) || (ban != f->ban))
 161                                                         {
 162                                                                 delete f;
 163                                                                 floodsettings *fs = new floodsettings(ban,nsecs,nlines);
 164                                                                 channel->Shrink("flood");
 165                                                                 channel->Extend("flood",fs);
 166                                                                 channel->SetModeParam('f', cur_param.c_str(), false);
 167                                                                 channel->SetModeParam('f', parameter.c_str(), true);
 168                                                                 return MODEACTION_ALLOW;
 169                                                         }
 170                                                         else
 171                                                         {
 172                                                                 return MODEACTION_DENY;
 173                                                         }
 174                                                 }
 175                                         }
 176                                 }
 177                         }
 178                         else
 179                         {
 180                                 source->WriteNumeric(608, "%s %s :Invalid flood parameter",source->nick,channel->name);
 181                                 parameter.clear();
 182                                 return MODEACTION_DENY;
 183                         }
 184                 }
 185                 else
 186                 {
 187                         if (channel->GetExt("flood", f))
 188                         {
 189                                 delete f;
 190                                 channel->Shrink("flood");
 191                                 channel->SetMode('f', false);
 192                                 return MODEACTION_ALLOW;
 193                         }
 194                 }
 195
 196                 return MODEACTION_DENY;
 197         }
 198 };
 199
 200 class ModuleMsgFlood : public Module
 201 {
 202
 203         MsgFlood* mf;
 204
 205  public:
 206
 207         ModuleMsgFlood(InspIRCd* Me)
 208                 : Module(Me)
 209         {
 210
 211                 mf = new MsgFlood(ServerInstance);
 212                 if (!ServerInstance->Modes->AddMode(mf))
 213                         throw ModuleException("Could not add new modes!");
 214                 Implementation eventlist[] = { I_OnChannelDelete, I_OnUserPreNotice, I_OnUserPreMessage };
 215                 ServerInstance->Modules->Attach(eventlist, this, 3);
 216         }
 217
 218         int ProcessMessages(User* user,Channel* dest, const std::string &text)
 219         {
 220                 if (!IS_LOCAL(user) || CHANOPS_EXEMPT(ServerInstance, 'f') && dest->GetStatus(user) == STATUS_OP)
 221                 {
 222                         return 0;
 223                 }
 224
 225                 floodsettings *f;
 226                 if (dest->GetExt("flood", f))
 227                 {
 228                         f->addmessage(user);
 229                         if (f->shouldkick(user))
 230                         {
 231                                 /* Youre outttta here! */
 232                                 f->clear(user);
 233                                 if (f->ban)
 234                                 {
 235                                         const char* parameters[3];
 236                                         parameters[0] = dest->name;
 237                                         parameters[1] = "+b";
 238                                         parameters[2] = user->MakeWildHost();
 239                                         ServerInstance->SendMode(parameters,3,user);
 240
 241                                         ServerInstance->PI->SendMode(dest->name, std::string("+b ") + user->MakeWildhost());
 242                                 }
 243                                 char kickmessage[MAXBUF];
 244                                 snprintf(kickmessage, MAXBUF, "Channel flood triggered (limit is %d lines in %d secs)", f->lines, f->secs);
 245                                 if (!dest->ServerKickUser(user, kickmessage, true))
 246                                 {
 247                                         delete dest;
 248                                         return 1;
 249                                 }
 250                         }
 251                 }
 252
 253                 return 0;
 254         }
 255
 256         virtual int OnUserPreMessage(User *user, void *dest, int target_type, std::string &text, char status, CUList &exempt_list)
 257         {
 258                 if (target_type == TYPE_CHANNEL)
 259                         return ProcessMessages(user,(Channel*)dest,text);
 260
 261                 return 0;
 262         }
 263
 264         virtual int OnUserPreNotice(User *user, void *dest, int target_type, std::string &text, char status, CUList &exempt_list)
 265         {
 266                 if (target_type == TYPE_CHANNEL)
 267                         return ProcessMessages(user,(Channel*)dest,text);
 268
 269                 return 0;
 270         }
 271
 272         void OnChannelDelete(Channel* chan)
 273         {
 274                 floodsettings* f;
 275                 if (chan->GetExt("flood", f))
 276                 {
 277                         delete f;
 278                         chan->Shrink("flood");
 279                 }
 280         }
 281
 282
 283         virtual ~ModuleMsgFlood()
 284         {
 285                 ServerInstance->Modes->DelMode(mf);
 286                 delete mf;
 287         }
 288
 289         virtual Version GetVersion()
 290         {
 291                 return Version(1, 2, 0, 0, VF_COMMON | VF_VENDOR, API_VERSION);
 292         }
 293 };
 294
 295 MODULE_INIT(ModuleMsgFlood)