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