src/modules/m_messageflood.cpp

   1 /*
   2  * InspIRCd -- Internet Relay Chat Daemon
   3  *
   4  *   Copyright (C) 2009 Daniel De Graaf <danieldg@inspircd.org>
   5  *   Copyright (C) 2008 Pippijn van Steenhoven <pip88nl@gmail.com>
   6  *   Copyright (C) 2007 Robin Burchell <robin+git@viroteck.net>
   7  *   Copyright (C) 2007 John Brooks <john.brooks@dereferenced.net>
   8  *   Copyright (C) 2007 Dennis Friis <peavey@inspircd.org>
   9  *   Copyright (C) 2006 Craig Edwards <craigedwards@brainbox.cc>
  10  *   Copyright (C) 2006 Oliver Lupton <oliverlupton@gmail.com>
  11  *
  12  * This file is part of InspIRCd.  InspIRCd is free software: you can
  13  * redistribute it and/or modify it under the terms of the GNU General Public
  14  * License as published by the Free Software Foundation, version 2.
  15  *
  16  * This program is distributed in the hope that it will be useful, but WITHOUT
  17  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  18  * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
  19  * details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  23  */
  24
  25
  26 #include "inspircd.h"
  27
  28 /* $ModDesc: Provides channel mode +f (message flood protection) */
  29
  30 /** Holds flood settings and state for mode +f
  31  */
  32 class floodsettings
  33 {
  34  public:
  35         bool ban;
  36         int secs;
  37         int lines;
  38         time_t reset;
  39         std::map<User*,int> counters;
  40
  41         floodsettings(bool a, int b, int c) : ban(a), secs(b), lines(c)
  42         {
  43                 reset = ServerInstance->Time() + secs;
  44         }
  45
  46         bool addmessage(User* who)
  47         {
  48                 if (ServerInstance->Time() > reset)
  49                 {
  50                         counters.clear();
  51                         reset = ServerInstance->Time() + secs;
  52                 }
  53
  54                 return (++counters[who] >= this->lines);
  55         }
  56
  57         void clear(User* who)
  58         {
  59                 std::map<User*,int>::iterator iter = counters.find(who);
  60                 if (iter != counters.end())
  61                 {
  62                         counters.erase(iter);
  63                 }
  64         }
  65 };
  66
  67 /** Handles channel mode +f
  68  */
  69 class MsgFlood : public ModeHandler
  70 {
  71  public:
  72         SimpleExtItem<floodsettings> ext;
  73         MsgFlood(Module* Creator) : ModeHandler(Creator, "flood", 'f', PARAM_SETONLY, MODETYPE_CHANNEL),
  74                 ext("messageflood", Creator) { }
  75
  76         ModeAction OnModeChange(User* source, User* dest, Channel* channel, std::string &parameter, bool adding)
  77         {
  78                 floodsettings *f = ext.get(channel);
  79
  80                 if (adding)
  81                 {
  82                         char ndata[MAXBUF];
  83                         char* data = ndata;
  84                         strlcpy(ndata,parameter.c_str(),MAXBUF);
  85                         char* lines = data;
  86                         char* secs = NULL;
  87                         bool ban = false;
  88                         if (*data == '*')
  89                         {
  90                                 ban = true;
  91                                 lines++;
  92                         }
  93                         else
  94                         {
  95                                 ban = false;
  96                         }
  97                         while (*data)
  98                         {
  99                                 if (*data == ':')
 100                                 {
 101                                         *data = 0;
 102                                         data++;
 103                                         secs = data;
 104                                         break;
 105                                 }
 106                                 else data++;
 107                         }
 108                         if (secs)
 109                         {
 110                                 /* Set up the flood parameters for this channel */
 111                                 int nlines = atoi(lines);
 112                                 int nsecs = atoi(secs);
 113                                 if ((nlines<2) || (nsecs<1))
 114                                 {
 115                                         source->WriteNumeric(608, "%s %s :Invalid flood parameter",source->nick.c_str(),channel->name.c_str());
 116                                         parameter.clear();
 117                                         return MODEACTION_DENY;
 118                                 }
 119                                 else
 120                                 {
 121                                         if (!f)
 122                                         {
 123                                                 parameter = std::string(ban ? "*" : "") + ConvToStr(nlines) + ":" +ConvToStr(nsecs);
 124                                                 f = new floodsettings(ban,nsecs,nlines);
 125                                                 ext.set(channel, f);
 126                                                 channel->SetModeParam('f', parameter);
 127                                                 return MODEACTION_ALLOW;
 128                                         }
 129                                         else
 130                                         {
 131                                                 std::string cur_param = channel->GetModeParameter('f');
 132                                                 parameter = std::string(ban ? "*" : "") + ConvToStr(nlines) + ":" +ConvToStr(nsecs);
 133                                                 if (cur_param == parameter)
 134                                                 {
 135                                                         // mode params match
 136                                                         return MODEACTION_DENY;
 137                                                 }
 138                                                 else
 139                                                 {
 140                                                         if ((((nlines != f->lines) || (nsecs != f->secs) || (ban != f->ban))) && (((nsecs > 0) && (nlines > 0))))
 141                                                         {
 142                                                                 floodsettings *fs = new floodsettings(ban,nsecs,nlines);
 143                                                                 ext.set(channel, fs);
 144                                                                 channel->SetModeParam('f', parameter);
 145                                                                 return MODEACTION_ALLOW;
 146                                                         }
 147                                                         else
 148                                                         {
 149                                                                 return MODEACTION_DENY;
 150                                                         }
 151                                                 }
 152                                         }
 153                                 }
 154                         }
 155                         else
 156                         {
 157                                 source->WriteNumeric(608, "%s %s :Invalid flood parameter",source->nick.c_str(),channel->name.c_str());
 158                                 parameter.clear();
 159                                 return MODEACTION_DENY;
 160                         }
 161                 }
 162                 else
 163                 {
 164                         if (f)
 165                         {
 166                                 ext.unset(channel);
 167                                 channel->SetModeParam('f', "");
 168                                 return MODEACTION_ALLOW;
 169                         }
 170                 }
 171
 172                 return MODEACTION_DENY;
 173         }
 174 };
 175
 176 class ModuleMsgFlood : public Module
 177 {
 178         MsgFlood mf;
 179
 180  public:
 181
 182         ModuleMsgFlood()
 183                 : mf(this)
 184         {
 185                 if (!ServerInstance->Modes->AddMode(&mf))
 186                         throw ModuleException("Could not add new modes!");
 187                 ServerInstance->Extensions.Register(&mf.ext);
 188                 Implementation eventlist[] = { I_OnUserPreNotice, I_OnUserPreMessage };
 189                 ServerInstance->Modules->Attach(eventlist, this, 2);
 190         }
 191
 192         ModResult ProcessMessages(User* user,Channel* dest, const std::string &text)
 193         {
 194                 ModResult res = ServerInstance->OnCheckExemption(user,dest,"flood");
 195                 if (!IS_LOCAL(user) || res == MOD_RES_ALLOW)
 196                         return MOD_RES_PASSTHRU;
 197
 198                 floodsettings *f = mf.ext.get(dest);
 199                 if (f)
 200                 {
 201                         if (f->addmessage(user))
 202                         {
 203                                 /* Youre outttta here! */
 204                                 f->clear(user);
 205                                 if (f->ban)
 206                                 {
 207                                         std::vector<std::string> parameters;
 208                                         parameters.push_back(dest->name);
 209                                         parameters.push_back("+b");
 210                                         parameters.push_back(user->MakeWildHost());
 211                                         ServerInstance->SendGlobalMode(parameters, ServerInstance->FakeClient);
 212                                 }
 213
 214                                 char kickmessage[MAXBUF];
 215                                 snprintf(kickmessage, MAXBUF, "Channel flood triggered (limit is %d lines in %d secs)", f->lines, f->secs);
 216
 217                                 dest->KickUser(ServerInstance->FakeClient, user, kickmessage);
 218
 219                                 return MOD_RES_DENY;
 220                         }
 221                 }
 222
 223                 return MOD_RES_PASSTHRU;
 224         }
 225
 226         ModResult OnUserPreMessage(User *user, void *dest, int target_type, std::string &text, char status, CUList &exempt_list)
 227         {
 228                 if (target_type == TYPE_CHANNEL)
 229                         return ProcessMessages(user,(Channel*)dest,text);
 230
 231                 return MOD_RES_PASSTHRU;
 232         }
 233
 234         ModResult OnUserPreNotice(User *user, void *dest, int target_type, std::string &text, char status, CUList &exempt_list)
 235         {
 236                 if (target_type == TYPE_CHANNEL)
 237                         return ProcessMessages(user,(Channel*)dest,text);
 238
 239                 return MOD_RES_PASSTHRU;
 240         }
 241
 242         ~ModuleMsgFlood()
 243         {
 244         }
 245
 246         Version GetVersion()
 247         {
 248                 return Version("Provides channel mode +f (message flood protection)", VF_VENDOR);
 249         }
 250 };
 251
 252 MODULE_INIT(ModuleMsgFlood)