src/modules/m_messageflood.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd: (C) 2002-2007 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 <stdio.h>
  15 #include <map>
  16 #include "users.h"
  17 #include "channels.h"
  18 #include "modules.h"
  19 #include "inspircd.h"
  20
  21 /* $ModDesc: Provides channel mode +f (message flood protection) */
  22
  23 /** Holds flood settings and state for mode +f
  24  */
  25 class floodsettings : public classbase
  26 {
  27  public:
  28         bool ban;
  29         int secs;
  30         int lines;
  31         time_t reset;
  32         std::map<userrec*,int> counters;
  33
  34         floodsettings() : ban(0), secs(0), lines(0) {};
  35         floodsettings(bool a, int b, int c) : ban(a), secs(b), lines(c)
  36         {
  37                 reset = time(NULL) + secs;
  38         };
  39
  40         void addmessage(userrec* who)
  41         {
  42                 std::map<userrec*,int>::iterator iter = counters.find(who);
  43                 if (iter != counters.end())
  44                 {
  45                         iter->second++;
  46                 }
  47                 else
  48                 {
  49                         counters[who] = 1;
  50                 }
  51                 if (time(NULL) > reset)
  52                 {
  53                         counters.clear();
  54                         reset = time(NULL) + secs;
  55                 }
  56         }
  57
  58         bool shouldkick(userrec* who)
  59         {
  60                 std::map<userrec*,int>::iterator iter = counters.find(who);
  61                 if (iter != counters.end())
  62                 {
  63                         return (iter->second >= this->lines);
  64                 }
  65                 else return false;
  66         }
  67
  68         void clear(userrec* who)
  69         {
  70                 std::map<userrec*,int>::iterator iter = counters.find(who);
  71                 if (iter != counters.end())
  72                 {
  73                         counters.erase(iter);
  74                 }
  75         }
  76 };
  77
  78 /** Handles channel mode +f
  79  */
  80 class MsgFlood : public ModeHandler
  81 {
  82  public:
  83         MsgFlood(InspIRCd* Instance) : ModeHandler(Instance, 'f', 1, 0, false, MODETYPE_CHANNEL, false) { }
  84
  85         ModePair ModeSet(userrec* source, userrec* dest, chanrec* channel, const std::string &parameter)
  86         {
  87                 floodsettings* x;
  88                 if (channel->GetExt("flood",x))
  89                         return std::make_pair(true, (x->ban ? "*" : "")+ConvToStr(x->lines)+":"+ConvToStr(x->secs));
  90                 else
  91                         return std::make_pair(false, parameter);
  92         }
  93
  94         bool CheckTimeStamp(time_t theirs, time_t ours, const std::string &their_param, const std::string &our_param, chanrec* channel)
  95         {
  96                 /* When TS is equal, the alphabetically later one wins */
  97                 return (their_param < our_param);
  98         }
  99
 100         ModeAction OnModeChange(userrec* source, userrec* dest, chanrec* channel, std::string &parameter, bool adding)
 101         {
 102                 floodsettings *f;
 103
 104                 if (adding)
 105                 {
 106                         char ndata[MAXBUF];
 107                         char* data = ndata;
 108                         strlcpy(ndata,parameter.c_str(),MAXBUF);
 109                         char* lines = data;
 110                         char* secs = NULL;
 111                         bool ban = false;
 112                         if (*data == '*')
 113                         {
 114                                 ban = true;
 115                                 lines++;
 116                         }
 117                         else
 118                         {
 119                                 ban = false;
 120                         }
 121                         while (*data)
 122                         {
 123                                 if (*data == ':')
 124                                 {
 125                                         *data = 0;
 126                                         data++;
 127                                         secs = data;
 128                                         break;
 129                                 }
 130                                 else data++;
 131                         }
 132                         if (secs)
 133                         {
 134                                 /* Set up the flood parameters for this channel */
 135                                 int nlines = atoi(lines);
 136                                 int nsecs = atoi(secs);
 137                                 if ((nlines<1) || (nsecs<1))
 138                                 {
 139                                         source->WriteServ("608 %s %s :Invalid flood parameter",source->nick,channel->name);
 140                                         parameter = "";
 141                                         return MODEACTION_DENY;
 142                                 }
 143                                 else
 144                                 {
 145                                         if (!channel->GetExt("flood", f))
 146                                         {
 147                                                 parameter = std::string(ban ? "*" : "") + ConvToStr(nlines) + ":" +ConvToStr(nsecs);
 148                                                 floodsettings *f = new floodsettings(ban,nsecs,nlines);
 149                                                 channel->Extend("flood",f);
 150                                                 channel->SetMode('f', true);
 151                                                 channel->SetModeParam('f', parameter.c_str(), true);
 152                                                 return MODEACTION_ALLOW;
 153                                         }
 154                                         else
 155                                         {
 156                                                 if (((nlines != f->lines) || (nsecs != f->secs)) && ((nsecs > 0) && (nlines > 0)) || (ban != f->ban))
 157                                                 {
 158                                                         delete f;
 159                                                         floodsettings *f = new floodsettings(ban,nsecs,nlines);
 160                                                         parameter = std::string(ban ? "*" : "") + ConvToStr(nlines) + ":" +ConvToStr(nsecs);
 161                                                         channel->Shrink("flood");
 162                                                         channel->Extend("flood",f);
 163                                                         channel->SetModeParam('f', parameter.c_str(), true);
 164                                                         return MODEACTION_ALLOW;
 165                                                 }
 166                                         }
 167                                 }
 168                         }
 169                         else
 170                         {
 171                                 source->WriteServ("608 %s %s :Invalid flood parameter",source->nick,channel->name);
 172                                 parameter = "";
 173                                 return MODEACTION_DENY;
 174                         }
 175                 }
 176                 else
 177                 {
 178                         if (channel->GetExt("flood", f))
 179                         {
 180                                 DELETE(f);
 181                                 channel->Shrink("flood");
 182                                 channel->SetMode('f', false);
 183                                 return MODEACTION_ALLOW;
 184                         }
 185                 }
 186
 187                 return MODEACTION_DENY;
 188         }
 189 };
 190
 191 class ModuleMsgFlood : public Module
 192 {
 193
 194         MsgFlood* mf;
 195
 196  public:
 197
 198         ModuleMsgFlood(InspIRCd* Me)
 199                 : Module::Module(Me)
 200         {
 201
 202                 mf = new MsgFlood(ServerInstance);
 203                 if (!ServerInstance->AddMode(mf, 'f'))
 204                         throw ModuleException("Could not add new modes!");
 205         }
 206
 207         void ProcessMessages(userrec* user,chanrec* dest, const std::string &text)
 208         {
 209                 if (IS_LOCAL(user))
 210                 {
 211                         floodsettings *f;
 212                         if (dest->GetExt("flood", f))
 213                         {
 214                                 f->addmessage(user);
 215                                 if (f->shouldkick(user))
 216                                 {
 217                                         /* Youre outttta here! */
 218                                         f->clear(user);
 219                                         if (f->ban)
 220                                         {
 221                                                 const char* parameters[3];
 222                                                 parameters[0] = dest->name;
 223                                                 parameters[1] = "+b";
 224                                                 parameters[2] = user->MakeWildHost();
 225                                                 ServerInstance->SendMode(parameters,3,user);
 226                                                 std::deque<std::string> n;
 227                                                 /* Propogate the ban to other servers.
 228                                                  * We dont know what protocol we may be using,
 229                                                  * so this event is picked up by our protocol
 230                                                  * module and formed into a ban command that
 231                                                  * suits the protocol in use.
 232                                                  */
 233                                                 n.push_back(dest->name);
 234                                                 n.push_back("+b");
 235                                                 n.push_back(user->MakeWildHost());
 236                                                 Event rmode((char *)&n, NULL, "send_mode");
 237                                                 rmode.Send(ServerInstance);
 238                                         }
 239                                         char kickmessage[MAXBUF];
 240                                         snprintf(kickmessage, MAXBUF, "Channel flood triggered (limit is %d lines in %d secs)", f->lines, f->secs);
 241                                         dest->ServerKickUser(user, kickmessage, true);
 242                                 }
 243                         }
 244                 }
 245         }
 246
 247         virtual void OnUserMessage(userrec* user, void* dest, int target_type, const std::string &text, char status, const CUList &exempt_list)
 248         {
 249                 if (target_type == TYPE_CHANNEL)
 250                 {
 251                         ProcessMessages(user,(chanrec*)dest,text);
 252                 }
 253         }
 254
 255         virtual void OnUserNotice(userrec* user, void* dest, int target_type, const std::string &text, char status, const CUList &exempt_list)
 256         {
 257                 if (target_type == TYPE_CHANNEL)
 258                 {
 259                         ProcessMessages(user,(chanrec*)dest,text);
 260                 }
 261         }
 262
 263         void OnChannelDelete(chanrec* chan)
 264         {
 265                 floodsettings* f;
 266                 if (chan->GetExt("flood", f))
 267                 {
 268                         DELETE(f);
 269                         chan->Shrink("flood");
 270                 }
 271         }
 272
 273         void Implements(char* List)
 274         {
 275                 List[I_OnChannelDelete] = List[I_OnUserNotice] = List[I_OnUserMessage] = 1;
 276         }
 277
 278         virtual ~ModuleMsgFlood()
 279         {
 280                 ServerInstance->Modes->DelMode(mf);
 281                 DELETE(mf);
 282         }
 283
 284         virtual Version GetVersion()
 285         {
 286                 return Version(1, 1, 0, 0, VF_COMMON | VF_VENDOR, API_VERSION);
 287         }
 288 };
 289
 290
 291 class ModuleMsgFloodFactory : public ModuleFactory
 292 {
 293  public:
 294         ModuleMsgFloodFactory()
 295         {
 296         }
 297
 298         ~ModuleMsgFloodFactory()
 299         {
 300         }
 301
 302         virtual Module * CreateModule(InspIRCd* Me)
 303         {
 304                 return new ModuleMsgFlood(Me);
 305         }
 306
 307 };
 308
 309
 310 extern "C" void * init_module( void )
 311 {
 312         return new ModuleMsgFloodFactory;
 313 }
 314