src/modules/m_connflood.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd: (C) 2002-2009 InspIRCd Development Team
   6  * See: http://wiki.inspircd.org/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: Connection throttle */
  17
  18 int conns = 0, throttled = 0;
  19
  20 class ModuleConnFlood : public Module
  21 {
  22 private:
  23         int seconds, maxconns, timeout, boot_wait;
  24         time_t first;
  25         std::string quitmsg;
  26
  27         ConfigReader* conf;
  28
  29
  30 public:
  31         ModuleConnFlood()       {
  32
  33                 InitConf();
  34                 Implementation eventlist[] = { I_OnRehash, I_OnUserRegister };
  35                 ServerInstance->Modules->Attach(eventlist, this, 2);
  36         }
  37
  38         virtual ~ModuleConnFlood()
  39         {
  40         }
  41
  42         virtual Version GetVersion()
  43         {
  44                 return Version("Connection throttle", VF_VENDOR,API_VERSION);
  45         }
  46
  47         void InitConf()
  48         {
  49                 /* read configuration variables */
  50                 conf = new ConfigReader;
  51                 /* throttle configuration */
  52                 seconds = conf->ReadInteger("connflood", "seconds", 0, true);
  53                 maxconns = conf->ReadInteger("connflood", "maxconns", 0, true);
  54                 timeout = conf->ReadInteger("connflood", "timeout", 0, true);
  55                 quitmsg = conf->ReadValue("connflood", "quitmsg", 0);
  56
  57                 /* seconds to wait when the server just booted */
  58                 boot_wait = conf->ReadInteger("connflood", "bootwait", 0, true);
  59
  60                 first = ServerInstance->Time();
  61         }
  62
  63         virtual ModResult OnUserRegister(User* user)
  64         {
  65                 time_t next = ServerInstance->Time();
  66
  67                 if ((ServerInstance->startup_time + boot_wait) > next)
  68                         return MOD_RES_PASSTHRU;
  69
  70                 /* time difference between first and latest connection */
  71                 time_t tdiff = next - first;
  72
  73                 /* increase connection count */
  74                 conns++;
  75
  76                 if (throttled == 1)
  77                 {
  78                         if (tdiff > seconds + timeout)
  79                         {
  80                                 /* expire throttle */
  81                                 throttled = 0;
  82                                 ServerInstance->SNO->WriteGlobalSno('a', "Connection throttle deactivated");
  83                                 return MOD_RES_PASSTHRU;
  84                         }
  85
  86                         ServerInstance->Users->QuitUser(user, quitmsg);
  87                         return MOD_RES_DENY;
  88                 }
  89
  90                 if (tdiff <= seconds)
  91                 {
  92                         if (conns >= maxconns)
  93                         {
  94                                 throttled = 1;
  95                                 ServerInstance->SNO->WriteGlobalSno('a', "Connection throttle activated");
  96                                 ServerInstance->Users->QuitUser(user, quitmsg);
  97                                 return MOD_RES_DENY;
  98                         }
  99                 }
 100                 else
 101                 {
 102                         conns = 1;
 103                         first = next;
 104                 }
 105                 return MOD_RES_PASSTHRU;
 106         }
 107
 108         virtual void OnRehash(User* user)
 109         {
 110                 InitConf();
 111         }
 112
 113 };
 114
 115 MODULE_INIT(ModuleConnFlood)