src/modules/m_connflood.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd: (C) 2002-2010 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 public:
  28         ModuleConnFlood()       {
  29
  30                 InitConf();
  31                 Implementation eventlist[] = { I_OnRehash, I_OnUserRegister };
  32                 ServerInstance->Modules->Attach(eventlist, this, 2);
  33         }
  34
  35         virtual ~ModuleConnFlood()
  36         {
  37         }
  38
  39         virtual Version GetVersion()
  40         {
  41                 return Version("Connection throttle", VF_VENDOR);
  42         }
  43
  44         void InitConf()
  45         {
  46                 /* read configuration variables */
  47                 ConfigReader conf;
  48                 /* throttle configuration */
  49                 seconds = conf.ReadInteger("connflood", "seconds", 0, true);
  50                 maxconns = conf.ReadInteger("connflood", "maxconns", 0, true);
  51                 timeout = conf.ReadInteger("connflood", "timeout", 0, true);
  52                 quitmsg = conf.ReadValue("connflood", "quitmsg", 0);
  53
  54                 /* seconds to wait when the server just booted */
  55                 boot_wait = conf.ReadInteger("connflood", "bootwait", 0, true);
  56
  57                 first = ServerInstance->Time();
  58         }
  59
  60         virtual ModResult OnUserRegister(LocalUser* user)
  61         {
  62                 time_t next = ServerInstance->Time();
  63
  64                 if ((ServerInstance->startup_time + boot_wait) > next)
  65                         return MOD_RES_PASSTHRU;
  66
  67                 /* time difference between first and latest connection */
  68                 time_t tdiff = next - first;
  69
  70                 /* increase connection count */
  71                 conns++;
  72
  73                 if (throttled == 1)
  74                 {
  75                         if (tdiff > seconds + timeout)
  76                         {
  77                                 /* expire throttle */
  78                                 throttled = 0;
  79                                 ServerInstance->SNO->WriteGlobalSno('a', "Connection throttle deactivated");
  80                                 return MOD_RES_PASSTHRU;
  81                         }
  82
  83                         ServerInstance->Users->QuitUser(user, quitmsg);
  84                         return MOD_RES_DENY;
  85                 }
  86
  87                 if (tdiff <= seconds)
  88                 {
  89                         if (conns >= maxconns)
  90                         {
  91                                 throttled = 1;
  92                                 ServerInstance->SNO->WriteGlobalSno('a', "Connection throttle activated");
  93                                 ServerInstance->Users->QuitUser(user, quitmsg);
  94                                 return MOD_RES_DENY;
  95                         }
  96                 }
  97                 else
  98                 {
  99                         conns = 1;
 100                         first = next;
 101                 }
 102                 return MOD_RES_PASSTHRU;
 103         }
 104
 105         virtual void OnRehash(User* user)
 106         {
 107                 InitConf();
 108         }
 109
 110 };
 111
 112 MODULE_INIT(ModuleConnFlood)