src/modules/m_nickflood.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd: (C) 2002-2008 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
  16 /* $ModDesc: Provides channel mode +F (nick flood protection) */
  17
  18 /** Holds settings and state associated with channel mode +F
  19  */
  20 class nickfloodsettings : public classbase
  21 {
  22  private:
  23         InspIRCd* ServerInstance;
  24  public:
  25         int secs;
  26         int nicks;
  27         time_t reset;
  28         time_t unlocktime;
  29         int counter;
  30         bool locked;
  31
  32         nickfloodsettings(InspIRCd *Instance, int b, int c) : ServerInstance(Instance), secs(b), nicks(c)
  33         {
  34                 reset = Instance->Time() + secs;
  35                 counter = 0;
  36                 locked = false;
  37         };
  38
  39         void addnick()
  40         {
  41                 counter++;
  42                 if (ServerInstance->Time() > reset)
  43                 {
  44                         counter = 0;
  45                         reset = ServerInstance->Time() + secs;
  46                 }
  47         }
  48
  49         bool shouldlock()
  50         {
  51                 return (counter >= this->nicks);
  52         }
  53
  54         void clear()
  55         {
  56                 counter = 0;
  57         }
  58
  59         bool islocked()
  60         {
  61                 if (locked)
  62                 {
  63                         if (ServerInstance->Time() > unlocktime)
  64                         {
  65                                 locked = false;
  66                                 return false;
  67                         }
  68                         else
  69                         {
  70                                 return true;
  71                         }
  72                 }
  73                 return false;
  74         }
  75
  76         void lock()
  77         {
  78                 locked = true;
  79                 unlocktime = ServerInstance->Time() + 60;
  80         }
  81
  82 };
  83
  84 /** Handles channel mode +j
  85  */
  86 class NickFlood : public ModeHandler
  87 {
  88  public:
  89         NickFlood(InspIRCd* Instance) : ModeHandler(Instance, 'F', 1, 0, false, MODETYPE_CHANNEL, false) { }
  90
  91         ModePair ModeSet(User* source, User* dest, Channel* channel, const std::string &parameter)
  92         {
  93                 nickfloodsettings* x;
  94                 if (channel->GetExt("nickflood",x))
  95                         return std::make_pair(true, ConvToStr(x->nicks)+":"+ConvToStr(x->secs));
  96                 else
  97                         return std::make_pair(false, parameter);
  98         }
  99
 100         bool CheckTimeStamp(time_t theirs, time_t ours, const std::string &their_param, const std::string &our_param, Channel* channel)
 101         {
 102                 /* When TS is equal, the alphabetically later one wins */
 103                 return (their_param < our_param);
 104         }
 105
 106         ModeAction OnModeChange(User* source, User* dest, Channel* channel, std::string &parameter, bool adding, bool)
 107         {
 108                 nickfloodsettings* dummy;
 109
 110                 if (adding)
 111                 {
 112                         char ndata[MAXBUF];
 113                         char* data = ndata;
 114                         strlcpy(ndata,parameter.c_str(),MAXBUF);
 115                         char* nicks = data;
 116                         char* secs = NULL;
 117                         while (*data)
 118                         {
 119                                 if (*data == ':')
 120                                 {
 121                                         *data = 0;
 122                                         data++;
 123                                         secs = data;
 124                                         break;
 125                                 }
 126                                 else data++;
 127                         }
 128                         if (secs)
 129
 130                         {
 131                                 /* Set up the flood parameters for this channel */
 132                                 int nnicks = atoi(nicks);
 133                                 int nsecs = atoi(secs);
 134                                 if ((nnicks<1) || (nsecs<1))
 135                                 {
 136                                         source->WriteNumeric(608, "%s %s :Invalid flood parameter",source->nick.c_str(),channel->name.c_str());
 137                                         parameter.clear();
 138                                         return MODEACTION_DENY;
 139                                 }
 140                                 else
 141                                 {
 142                                         if (!channel->GetExt("nickflood", dummy))
 143                                         {
 144                                                 parameter = ConvToStr(nnicks) + ":" +ConvToStr(nsecs);
 145                                                 nickfloodsettings *f = new nickfloodsettings(ServerInstance, nsecs, nnicks);
 146                                                 channel->Extend("nickflood", f);
 147                                                 channel->SetMode('F', true);
 148                                                 channel->SetModeParam('F', parameter.c_str(), true);
 149                                                 return MODEACTION_ALLOW;
 150                                         }
 151                                         else
 152                                         {
 153                                                 std::string cur_param = channel->GetModeParameter('F');
 154                                                 parameter = ConvToStr(nnicks) + ":" +ConvToStr(nsecs);
 155                                                 if (cur_param == parameter)
 156                                                 {
 157                                                         // mode params match
 158                                                         return MODEACTION_DENY;
 159                                                 }
 160                                                 else
 161                                                 {
 162                                                         // new mode param, replace old with new
 163                                                         if ((nsecs > 0) && (nnicks > 0))
 164                                                         {
 165                                                                 nickfloodsettings* f;
 166                                                                 channel->GetExt("nickflood", f);
 167                                                                 delete f;
 168                                                                 f = new nickfloodsettings(ServerInstance, nsecs, nnicks);
 169                                                                 channel->Shrink("nickflood");
 170                                                                 channel->Extend("nickflood", f);
 171                                                                 channel->SetModeParam('F', cur_param.c_str(), false);
 172                                                                 channel->SetModeParam('F', parameter.c_str(), true);
 173                                                                 return MODEACTION_ALLOW;
 174                                                         }
 175                                                         else
 176                                                         {
 177                                                                 return MODEACTION_DENY;
 178                                                         }
 179                                                 }
 180                                         }
 181                                 }
 182                         }
 183                         else
 184                         {
 185                                 source->WriteNumeric(608, "%s %s :Invalid flood parameter",source->nick.c_str(),channel->name.c_str());
 186                                 return MODEACTION_DENY;
 187                         }
 188                 }
 189                 else
 190                 {
 191                         if (channel->GetExt("nickflood", dummy))
 192                         {
 193                                 nickfloodsettings *f;
 194                                 channel->GetExt("nickflood", f);
 195                                 delete f;
 196                                 channel->Shrink("nickflood");
 197                                 channel->SetMode('F', false);
 198                                 return MODEACTION_ALLOW;
 199                         }
 200                 }
 201                 return MODEACTION_DENY;
 202         }
 203 };
 204
 205 class ModuleNickFlood : public Module
 206 {
 207         NickFlood* jf;
 208
 209  public:
 210
 211         ModuleNickFlood(InspIRCd* Me)
 212                 : Module(Me)
 213         {
 214
 215                 jf = new NickFlood(ServerInstance);
 216                 if (!ServerInstance->Modes->AddMode(jf))
 217                         throw ModuleException("Could not add new modes!");
 218                 Implementation eventlist[] = { I_OnChannelDelete, I_OnUserPreNick };
 219                 ServerInstance->Modules->Attach(eventlist, this, 2);
 220         }
 221
 222         virtual int OnUserPreNick(User* user, const std::string &newnick)
 223         {
 224                 if (isdigit(newnick[0])) /* allow switches to UID */
 225                         return 0;
 226
 227                 for (UCListIter i = user->chans.begin(); i != user->chans.end(); i++)
 228                 {
 229                         Channel *channel = i->first;
 230
 231                         nickfloodsettings *f;
 232                         if (channel->GetExt("nickflood", f))
 233                         {
 234                                 if (CHANOPS_EXEMPT(ServerInstance, 'F') && channel->GetStatus(user) == STATUS_OP)
 235                                         continue;
 236
 237                                 if (f->islocked())
 238                                 {
 239                                         user->WriteNumeric(447, "%s :%s has been locked for nickchanges for 60 seconds because there have been more than %d nick changes in %d seconds", user->nick.c_str(), channel->name.c_str(), f->nicks, f->secs);
 240                                         return 1;
 241                                 }
 242
 243                                 f->addnick();
 244                                 if (f->shouldlock())
 245                                 {
 246                                         f->clear();
 247                                         f->lock();
 248                                         channel->WriteChannelWithServ((char*)ServerInstance->Config->ServerName, "NOTICE %s :No nick changes are allowed for 60 seconds because there have been more than %d nick changes in %d seconds.", channel->name.c_str(), f->nicks, f->secs);
 249                                         return 1;
 250                                 }
 251                         }
 252                 }
 253
 254                 return 0;
 255         }
 256
 257         void OnChannelDelete(Channel* chan)
 258         {
 259                 nickfloodsettings *f;
 260                 if (chan->GetExt("nickflood",f))
 261                 {
 262                         delete f;
 263                         chan->Shrink("nickflood");
 264                 }
 265         }
 266
 267
 268         virtual ~ModuleNickFlood()
 269         {
 270                 ServerInstance->Modes->DelMode(jf);
 271                 delete jf;
 272         }
 273
 274         virtual Version GetVersion()
 275         {
 276                 return Version("$Id$", VF_COMMON | VF_VENDOR, API_VERSION);
 277         }
 278 };
 279
 280 MODULE_INIT(ModuleNickFlood)