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