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 #include "users.h"
  16 #include "channels.h"
  17 #include "modules.h"
  18
  19 /* $ModDesc: Provides channel mode +F (nick flood protection) */
  20
  21 /** Holds settings and state associated with channel mode +F
  22  */
  23 class nickfloodsettings : public classbase
  24 {
  25  public:
  26
  27         int secs;
  28         int nicks;
  29         time_t reset;
  30         time_t unlocktime;
  31         int counter;
  32         bool locked;
  33         InspIRCd* ServerInstance;
  34
  35         nickfloodsettings() : secs(0), nicks(0) {};
  36
  37         nickfloodsettings(int b, int c) : secs(b), nicks(c)
  38         {
  39                 reset = time(NULL) + secs;
  40                 counter = 0;
  41                 locked = false;
  42         };
  43
  44         void addnick()
  45         {
  46                 counter++;
  47                 if (time(NULL) > reset)
  48                 {
  49                         counter = 0;
  50                         reset = time(NULL) + secs;
  51                 }
  52         }
  53
  54         bool shouldlock()
  55         {
  56                 return (counter >= this->nicks);
  57         }
  58
  59         void clear()
  60         {
  61                 counter = 0;
  62         }
  63
  64         bool islocked()
  65         {
  66                 if (locked)
  67                 {
  68                         if (time(NULL) > unlocktime)
  69                         {
  70                                 locked = false;
  71                                 return false;
  72                         }
  73                         else
  74                         {
  75                                 return true;
  76                         }
  77                 }
  78                 return false;
  79         }
  80
  81         void lock()
  82         {
  83                 locked = true;
  84                 unlocktime = time(NULL) + 60;
  85         }
  86
  87 };
  88
  89 /** Handles channel mode +j
  90  */
  91 class NickFlood : public ModeHandler
  92 {
  93  public:
  94         NickFlood(InspIRCd* Instance) : ModeHandler(Instance, 'F', 1, 0, false, MODETYPE_CHANNEL, false) { }
  95
  96         ModePair ModeSet(userrec* source, userrec* dest, chanrec* channel, const std::string &parameter)
  97         {
  98                 nickfloodsettings* x;
  99                 if (channel->GetExt("nickflood",x))
 100                         return std::make_pair(true, ConvToStr(x->nicks)+":"+ConvToStr(x->secs));
 101                 else
 102                         return std::make_pair(false, parameter);
 103         }
 104
 105         bool CheckTimeStamp(time_t theirs, time_t ours, const std::string &their_param, const std::string &our_param, chanrec* channel)
 106         {
 107                 /* When TS is equal, the alphabetically later one wins */
 108                 return (their_param < our_param);
 109         }
 110
 111         ModeAction OnModeChange(userrec* source, userrec* dest, chanrec* channel, std::string &parameter, bool adding)
 112         {
 113                 nickfloodsettings* dummy;
 114
 115                 if (adding)
 116                 {
 117                         char ndata[MAXBUF];
 118                         char* data = ndata;
 119                         strlcpy(ndata,parameter.c_str(),MAXBUF);
 120                         char* nicks = data;
 121                         char* secs = NULL;
 122                         while (*data)
 123                         {
 124                                 if (*data == ':')
 125                                 {
 126                                         *data = 0;
 127                                         data++;
 128                                         secs = data;
 129                                         break;
 130                                 }
 131                                 else data++;
 132                         }
 133                         if (secs)
 134
 135                         {
 136                                 /* Set up the flood parameters for this channel */
 137                                 int nnicks = atoi(nicks);
 138                                 int nsecs = atoi(secs);
 139                                 if ((nnicks<1) || (nsecs<1))
 140                                 {
 141                                         source->WriteServ("608 %s %s :Invalid flood parameter",source->nick,channel->name);
 142                                         parameter.clear();
 143                                         return MODEACTION_DENY;
 144                                 }
 145                                 else
 146                                 {
 147                                         if (!channel->GetExt("nickflood", dummy))
 148                                         {
 149                                                 parameter = ConvToStr(nnicks) + ":" +ConvToStr(nsecs);
 150                                                 nickfloodsettings *f = new nickfloodsettings(nsecs,nnicks);
 151                                                 channel->Extend("nickflood", f);
 152                                                 channel->SetMode('F', true);
 153                                                 channel->SetModeParam('F', parameter.c_str(), true);
 154                                                 return MODEACTION_ALLOW;
 155                                         }
 156                                         else
 157                                         {
 158                                                 std::string cur_param = channel->GetModeParameter('F');
 159                                                 parameter = ConvToStr(nnicks) + ":" +ConvToStr(nsecs);
 160                                                 if (cur_param == parameter)
 161                                                 {
 162                                                         // mode params match
 163                                                         return MODEACTION_DENY;
 164                                                 }
 165                                                 else
 166                                                 {
 167                                                         // new mode param, replace old with new
 168                                                         if ((nsecs > 0) && (nnicks > 0))
 169                                                         {
 170                                                                 nickfloodsettings* f;
 171                                                                 channel->GetExt("nickflood", f);
 172                                                                 delete f;
 173                                                                 f = new nickfloodsettings(nsecs, nnicks);
 174                                                                 channel->Shrink("nickflood");
 175                                                                 channel->Extend("nickflood", f);
 176                                                                 channel->SetModeParam('F', cur_param.c_str(), false);
 177                                                                 channel->SetModeParam('F', parameter.c_str(), true);
 178                                                                 return MODEACTION_ALLOW;
 179                                                         }
 180                                                         else
 181                                                         {
 182                                                                 return MODEACTION_DENY;
 183                                                         }
 184                                                 }
 185                                         }
 186                                 }
 187                         }
 188                         else
 189                         {
 190                                 source->WriteServ("608 %s %s :Invalid flood parameter",source->nick,channel->name);
 191                                 return MODEACTION_DENY;
 192                         }
 193                 }
 194                 else
 195                 {
 196                         if (channel->GetExt("nickflood", dummy))
 197                         {
 198                                 nickfloodsettings *f;
 199                                 channel->GetExt("nickflood", f);
 200                                 DELETE(f);
 201                                 channel->Shrink("nickflood");
 202                                 channel->SetMode('F', false);
 203                                 return MODEACTION_ALLOW;
 204                         }
 205                 }
 206                 return MODEACTION_DENY;
 207         }
 208 };
 209
 210 class ModuleNickFlood : public Module
 211 {
 212         NickFlood* jf;
 213
 214  public:
 215
 216         ModuleNickFlood(InspIRCd* Me)
 217                 : Module(Me)
 218         {
 219
 220                 jf = new NickFlood(ServerInstance);
 221                 if (!ServerInstance->AddMode(jf, 'F'))
 222                         throw ModuleException("Could not add new modes!");
 223         }
 224
 225         virtual int OnUserPreNick(userrec* user, const std::string &newnick)
 226         {
 227                 for (UCListIter i = user->chans.begin(); i != user->chans.end(); i++)
 228                 {
 229                         chanrec *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(chanrec* 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)