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                                                 std::string cur_param = channel->GetModeParameter('f');
 155                                                 parameter = std::string(ban ? "*" : "") + ConvToStr(nlines) + ":" +ConvToStr(nsecs);
 156                                                 if (cur_param == parameter)
 157                                                 {
 158                                                         // mode params match
 159                                                         return MODEACTION_DENY;
 160                                                 }
 161                                                 else
 162                                                 {
 163                                                         if (((nlines != f->lines) || (nsecs != f->secs)) && ((nsecs > 0) && (nlines > 0)) || (ban != f->ban))
 164                                                         {
 165                                                                 delete f;
 166                                                                 floodsettings *f = new floodsettings(ban,nsecs,nlines);
 167                                                                 channel->Shrink("flood");
 168                                                                 channel->Extend("flood",f);
 169                                                                 channel->SetModeParam('f', cur_param.c_str(), false);
 170                                                                 channel->SetModeParam('f', parameter.c_str(), true);
 171                                                                 return MODEACTION_ALLOW;
 172                                                         }
 173                                                         else
 174                                                         {
 175                                                                 return MODEACTION_DENY;
 176                                                         }
 177                                                 }
 178                                         }
 179                                 }
 180                         }
 181                         else
 182                         {
 183                                 source->WriteServ("608 %s %s :Invalid flood parameter",source->nick,channel->name);
 184                                 parameter.clear();
 185                                 return MODEACTION_DENY;
 186                         }
 187                 }
 188                 else
 189                 {
 190                         if (channel->GetExt("flood", f))
 191                         {
 192                                 DELETE(f);
 193                                 channel->Shrink("flood");
 194                                 channel->SetMode('f', false);
 195                                 return MODEACTION_ALLOW;
 196                         }
 197                 }
 198
 199                 return MODEACTION_DENY;
 200         }
 201 };
 202
 203 class ModuleMsgFlood : public Module
 204 {
 205
 206         MsgFlood* mf;
 207
 208  public:
 209
 210         ModuleMsgFlood(InspIRCd* Me)
 211                 : Module(Me)
 212         {
 213
 214                 mf = new MsgFlood(ServerInstance);
 215                 if (!ServerInstance->AddMode(mf, 'f'))
 216                         throw ModuleException("Could not add new modes!");
 217         }
 218
 219         void ProcessMessages(userrec* user,chanrec* dest, const std::string &text)
 220         {
 221                 if (!IS_LOCAL(user) || CHANOPS_EXEMPT(ServerInstance, 'f') && dest->GetStatus(user) == STATUS_OP)
 222                 {
 223                         return;
 224                 }
 225
 226                 floodsettings *f;
 227                 if (dest->GetExt("flood", f))
 228                 {
 229                         f->addmessage(user);
 230                         if (f->shouldkick(user))
 231                         {
 232                                 /* Youre outttta here! */
 233                                 f->clear(user);
 234                                 if (f->ban)
 235                                 {
 236                                         const char* parameters[3];
 237                                         parameters[0] = dest->name;
 238                                         parameters[1] = "+b";
 239                                         parameters[2] = user->MakeWildHost();
 240                                         ServerInstance->SendMode(parameters,3,user);
 241                                         std::deque<std::string> n;
 242                                         /* Propogate the ban to other servers.
 243                                          * We dont know what protocol we may be using,
 244                                          * so this event is picked up by our protocol
 245                                          * module and formed into a ban command that
 246                                          * suits the protocol in use.
 247                                          */
 248                                         n.push_back(dest->name);
 249                                         n.push_back("+b");
 250                                         n.push_back(user->MakeWildHost());
 251                                         Event rmode((char *)&n, NULL, "send_mode");
 252                                         rmode.Send(ServerInstance);
 253                                 }
 254                                 char kickmessage[MAXBUF];
 255                                 snprintf(kickmessage, MAXBUF, "Channel flood triggered (limit is %d lines in %d secs)", f->lines, f->secs);
 256                                 dest->ServerKickUser(user, kickmessage, true);
 257                         }
 258                 }
 259         }
 260
 261         virtual void OnUserMessage(userrec* user, void* dest, int target_type, const std::string &text, char status, const CUList &exempt_list)
 262         {
 263                 if (target_type == TYPE_CHANNEL)
 264                 {
 265                         ProcessMessages(user,(chanrec*)dest,text);
 266                 }
 267         }
 268
 269         virtual void OnUserNotice(userrec* user, void* dest, int target_type, const std::string &text, char status, const CUList &exempt_list)
 270         {
 271                 if (target_type == TYPE_CHANNEL)
 272                 {
 273                         ProcessMessages(user,(chanrec*)dest,text);
 274                 }
 275         }
 276
 277         void OnChannelDelete(chanrec* chan)
 278         {
 279                 floodsettings* f;
 280                 if (chan->GetExt("flood", f))
 281                 {
 282                         DELETE(f);
 283                         chan->Shrink("flood");
 284                 }
 285         }
 286
 287         void Implements(char* List)
 288         {
 289                 List[I_OnChannelDelete] = List[I_OnUserNotice] = List[I_OnUserMessage] = 1;
 290         }
 291
 292         virtual ~ModuleMsgFlood()
 293         {
 294                 ServerInstance->Modes->DelMode(mf);
 295                 DELETE(mf);
 296         }
 297
 298         virtual Version GetVersion()
 299         {
 300                 return Version(1, 1, 0, 0, VF_COMMON | VF_VENDOR, API_VERSION);
 301         }
 302 };
 303
 304 MODULE_INIT(ModuleMsgFlood)