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         unsigned int secs;
  37         unsigned int lines;
  38         time_t reset;
  39         std::map<User*, unsigned 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*, unsigned 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                 if (adding)
  79                 {
  80                         std::string::size_type colon = parameter.find(':');
  81                         if ((colon == std::string::npos) || (parameter.find('-') != std::string::npos))
  82                         {
  83                                 source->WriteNumeric(608, "%s %s :Invalid flood parameter",source->nick.c_str(),channel->name.c_str());
  84                                 return MODEACTION_DENY;
  85                         }
  86
  87                         /* Set up the flood parameters for this channel */
  88                         bool ban = (parameter[0] == '*');
  89                         unsigned int nlines = ConvToInt(parameter.substr(ban ? 1 : 0, ban ? colon-1 : colon));
  90                         unsigned int nsecs = ConvToInt(parameter.substr(colon+1));
  91
  92                         if ((nlines<2) || (nsecs<1))
  93                         {
  94                                 source->WriteNumeric(608, "%s %s :Invalid flood parameter",source->nick.c_str(),channel->name.c_str());
  95                                 return MODEACTION_DENY;
  96                         }
  97
  98                         floodsettings* f = ext.get(channel);
  99                         if ((f) && (nlines == f->lines) && (nsecs == f->secs) && (ban == f->ban))
 100                                 // mode params match
 101                                 return MODEACTION_DENY;
 102
 103                         ext.set(channel, new floodsettings(ban, nsecs, nlines));
 104                         parameter = std::string(ban ? "*" : "") + ConvToStr(nlines) + ":" + ConvToStr(nsecs);
 105                         channel->SetModeParam('f', parameter);
 106                         return MODEACTION_ALLOW;
 107                 }
 108                 else
 109                 {
 110                         if (!channel->IsModeSet('f'))
 111                                 return MODEACTION_DENY;
 112
 113                         ext.unset(channel);
 114                         channel->SetModeParam('f', "");
 115                         return MODEACTION_ALLOW;
 116                 }
 117         }
 118 };
 119
 120 class ModuleMsgFlood : public Module
 121 {
 122         MsgFlood mf;
 123
 124  public:
 125
 126         ModuleMsgFlood()
 127                 : mf(this)
 128         {
 129         }
 130
 131         void init()
 132         {
 133                 ServerInstance->Modules->AddService(mf);
 134                 ServerInstance->Modules->AddService(mf.ext);
 135                 Implementation eventlist[] = { I_OnUserPreNotice, I_OnUserPreMessage };
 136                 ServerInstance->Modules->Attach(eventlist, this, sizeof(eventlist)/sizeof(Implementation));
 137         }
 138
 139         ModResult ProcessMessages(User* user,Channel* dest, const std::string &text)
 140         {
 141                 if ((!IS_LOCAL(user)) || !dest->IsModeSet('f'))
 142                         return MOD_RES_PASSTHRU;
 143
 144                 if (ServerInstance->OnCheckExemption(user,dest,"flood") == MOD_RES_ALLOW)
 145                         return MOD_RES_PASSTHRU;
 146
 147                 floodsettings *f = mf.ext.get(dest);
 148                 if (f)
 149                 {
 150                         if (f->addmessage(user))
 151                         {
 152                                 /* Youre outttta here! */
 153                                 f->clear(user);
 154                                 if (f->ban)
 155                                 {
 156                                         std::vector<std::string> parameters;
 157                                         parameters.push_back(dest->name);
 158                                         parameters.push_back("+b");
 159                                         parameters.push_back(user->MakeWildHost());
 160                                         ServerInstance->SendGlobalMode(parameters, ServerInstance->FakeClient);
 161                                 }
 162
 163                                 char kickmessage[MAXBUF];
 164                                 snprintf(kickmessage, MAXBUF, "Channel flood triggered (limit is %u lines in %u secs)", f->lines, f->secs);
 165
 166                                 dest->KickUser(ServerInstance->FakeClient, user, kickmessage);
 167
 168                                 return MOD_RES_DENY;
 169                         }
 170                 }
 171
 172                 return MOD_RES_PASSTHRU;
 173         }
 174
 175         ModResult OnUserPreMessage(User *user, void *dest, int target_type, std::string &text, char status, CUList &exempt_list)
 176         {
 177                 if (target_type == TYPE_CHANNEL)
 178                         return ProcessMessages(user,(Channel*)dest,text);
 179
 180                 return MOD_RES_PASSTHRU;
 181         }
 182
 183         ModResult OnUserPreNotice(User *user, void *dest, int target_type, std::string &text, char status, CUList &exempt_list)
 184         {
 185                 if (target_type == TYPE_CHANNEL)
 186                         return ProcessMessages(user,(Channel*)dest,text);
 187
 188                 return MOD_RES_PASSTHRU;
 189         }
 190
 191         void Prioritize()
 192         {
 193                 // we want to be after all modules that might deny the message (e.g. m_muteban, m_noctcp, m_blockcolor, etc.)
 194                 ServerInstance->Modules->SetPriority(this, I_OnUserPreMessage, PRIORITY_LAST);
 195                 ServerInstance->Modules->SetPriority(this, I_OnUserPreNotice, PRIORITY_LAST);
 196         }
 197
 198         Version GetVersion()
 199         {
 200                 return Version("Provides channel mode +f (message flood protection)", VF_VENDOR);
 201         }
 202 };
 203
 204 MODULE_INIT(ModuleMsgFlood)