src/modules/m_nickflood.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
  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  public:
  23
  24         int secs;
  25         int nicks;
  26         time_t reset;
  27         time_t unlocktime;
  28         int counter;
  29         bool locked;
  30         InspIRCd* ServerInstance;
  31
  32         nickfloodsettings() : secs(0), nicks(0) {};
  33
  34         nickfloodsettings(int b, int c) : secs(b), nicks(c)
  35         {
  36                 reset = time(NULL) + secs;
  37                 counter = 0;
  38                 locked = false;
  39         };
  40
  41         void addnick()
  42         {
  43                 counter++;
  44                 if (time(NULL) > reset)
  45                 {
  46                         counter = 0;
  47                         reset = time(NULL) + secs;
  48                 }
  49         }
  50
  51         bool shouldlock()
  52         {
  53                 return (counter >= this->nicks);
  54         }
  55
  56         void clear()
  57         {
  58                 counter = 0;
  59         }
  60
  61         bool islocked()
  62         {
  63                 if (locked)
  64                 {
  65                         if (time(NULL) > unlocktime)
  66                         {
  67                                 locked = false;
  68                                 return false;
  69                         }
  70                         else
  71                         {
  72                                 return true;
  73                         }
  74                 }
  75                 return false;
  76         }
  77
  78         void lock()
  79         {
  80                 locked = true;
  81                 unlocktime = time(NULL) + 60;
  82         }
  83
  84 };
  85
  86 /** Handles channel mode +j
  87  */
  88 class NickFlood : public ModeHandler
  89 {
  90  public:
  91         NickFlood(InspIRCd* Instance) : ModeHandler(Instance, 'F', 1, 0, false, MODETYPE_CHANNEL, false) { }
  92
  93         ModePair ModeSet(User* source, User* dest, Channel* channel, const std::string &parameter)
  94         {
  95                 nickfloodsettings* x;
  96                 if (channel->GetExt("nickflood",x))
  97                         return std::make_pair(true, ConvToStr(x->nicks)+":"+ConvToStr(x->secs));
  98                 else
  99                         return std::make_pair(false, parameter);
 100         }
 101
 102         bool CheckTimeStamp(time_t theirs, time_t ours, const std::string &their_param, const std::string &our_param, Channel* channel)
 103         {
 104                 /* When TS is equal, the alphabetically later one wins */
 105                 return (their_param < our_param);
 106         }
 107
 108         ModeAction OnModeChange(User* source, User* dest, Channel* channel, std::string &parameter, bool adding)
 109         {
 110                 nickfloodsettings* dummy;
 111
 112                 if (adding)
 113                 {
 114                         char ndata[MAXBUF];
 115                         char* data = ndata;
 116                         strlcpy(ndata,parameter.c_str(),MAXBUF);
 117                         char* nicks = data;
 118                         char* secs = NULL;
 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                         {
 133                                 /* Set up the flood parameters for this channel */
 134                                 int nnicks = atoi(nicks);
 135                                 int nsecs = atoi(secs);
 136                                 if ((nnicks<1) || (nsecs<1))
 137                                 {
 138                                         source->WriteServ("608 %s %s :Invalid flood parameter",source->nick,channel->name);
 139                                         parameter.clear();
 140                                         return MODEACTION_DENY;
 141                                 }
 142                                 else
 143                                 {
 144                                         if (!channel->GetExt("nickflood", dummy))
 145                                         {
 146                                                 parameter = ConvToStr(nnicks) + ":" +ConvToStr(nsecs);
 147                                                 nickfloodsettings *f = new nickfloodsettings(nsecs,nnicks);
 148                                                 channel->Extend("nickflood", f);
 149                                                 channel->SetMode('F', true);
 150                                                 channel->SetModeParam('F', parameter.c_str(), true);
 151                                                 return MODEACTION_ALLOW;
 152                                         }
 153                                         else
 154                                         {
 155                                                 std::string cur_param = channel->GetModeParameter('F');
 156                                                 parameter = ConvToStr(nnicks) + ":" +ConvToStr(nsecs);
 157                                                 if (cur_param == parameter)
 158                                                 {
 159                                                         // mode params match
 160                                                         return MODEACTION_DENY;
 161                                                 }
 162                                                 else
 163                                                 {
 164                                                         // new mode param, replace old with new
 165                                                         if ((nsecs > 0) && (nnicks > 0))
 166                                                         {
 167                                                                 nickfloodsettings* f;
 168                                                                 channel->GetExt("nickflood", f);
 169                                                                 delete f;
 170                                                                 f = new nickfloodsettings(nsecs, nnicks);
 171                                                                 channel->Shrink("nickflood");
 172                                                                 channel->Extend("nickflood", f);
 173                                                                 channel->SetModeParam('F', cur_param.c_str(), false);
 174                                                                 channel->SetModeParam('F', parameter.c_str(), true);
 175                                                                 return MODEACTION_ALLOW;
 176                                                         }
 177                                                         else
 178                                                         {
 179                                                                 return MODEACTION_DENY;
 180                                                         }
 181                                                 }
 182                                         }
 183                                 }
 184                         }
 185                         else
 186                         {
 187                                 source->WriteServ("608 %s %s :Invalid flood parameter",source->nick,channel->name);
 188                                 return MODEACTION_DENY;
 189                         }
 190                 }
 191                 else
 192                 {
 193                         if (channel->GetExt("nickflood", dummy))
 194                         {
 195                                 nickfloodsettings *f;
 196                                 channel->GetExt("nickflood", f);
 197                                 DELETE(f);
 198                                 channel->Shrink("nickflood");
 199                                 channel->SetMode('F', false);
 200                                 return MODEACTION_ALLOW;
 201                         }
 202                 }
 203                 return MODEACTION_DENY;
 204         }
 205 };
 206
 207 class ModuleNickFlood : public Module
 208 {
 209         NickFlood* jf;
 210
 211  public:
 212
 213         ModuleNickFlood(InspIRCd* Me)
 214                 : Module(Me)
 215         {
 216
 217                 jf = new NickFlood(ServerInstance);
 218                 if (!ServerInstance->AddMode(jf, 'F'))
 219                         throw ModuleException("Could not add new modes!");
 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->WriteServ("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, channel->name, 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, 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         void Implements(char* List)
 268         {
 269                 List[I_OnChannelDelete] = List[I_OnUserPreNick] = 1;
 270         }
 271
 272         virtual ~ModuleNickFlood()
 273         {
 274                 ServerInstance->Modes->DelMode(jf);
 275                 DELETE(jf);
 276         }
 277
 278         virtual Version GetVersion()
 279         {
 280                 return Version(1, 1, 0, 0, VF_COMMON | VF_VENDOR, API_VERSION);
 281         }
 282 };
 283
 284 MODULE_INIT(ModuleNickFlood)