src/modules/extra/m_filter_pcre.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd is copyright (C) 2002-2004 ChatSpike-Dev.
   6  *                       E-mail:
   7  *                <brain@chatspike.net>
   8  *                <Craig@chatspike.net>
   9  *
  10  * Written by Craig Edwards, Craig McLure, and others.
  11  * This program is free but copyrighted software; see
  12  *            the file COPYING for details.
  13  *
  14  * ---------------------------------------------------
  15  */
  16
  17 using namespace std;
  18
  19 // Message and notice filtering using regex patterns
  20 // a module based on the original work done by Craig Edwards in 2003
  21 // for the chatspike network.
  22
  23 #include <stdio.h>
  24 #include <string>
  25 #include <pcre.h>
  26 #include "users.h"
  27 #include "channels.h"
  28 #include "modules.h"
  29 #include "helperfuncs.h"
  30
  31 /* $ModDesc: m_filter with regexps */
  32 /* $CompileFlags: -I/usr/local/include */
  33 /* $LinkerFlags: -L/usr/local/lib -lpcre */
  34
  35 class ModuleFilterPCRE : public Module
  36 {
  37         Server *Srv;
  38         ConfigReader *Conf, *MyConf;
  39         std::vector<pcre*> filters;
  40         pcre *re;
  41         const char *error;
  42         int erroffset;
  43
  44  public:
  45         ModuleFilterPCRE(Server* Me)
  46                 : Module::Module(Me)
  47         {
  48                 // read the configuration file on startup.
  49                 // it is perfectly valid to set <filter file> to the value of the
  50                 // main config file, then append your <keyword> tags to the bottom
  51                 // of the main config... but rather messy. That's why the capability
  52                 // of using a seperate config file is provided.
  53                 Srv = Me;
  54                 Conf = new ConfigReader;
  55                 std::string filterfile = Conf->ReadValue("filter","file",0);
  56                 MyConf = new ConfigReader(filterfile);
  57                 if ((filterfile == "") || (!MyConf->Verify()))
  58                 {
  59                         printf("Error, could not find <filter file=\"\"> definition in your config file!\n");
  60                         log(DEFAULT,"Error, could not find <filter file=\"\"> definition in your config file!");
  61                         return;
  62                 }
  63                 Srv->Log(DEFAULT,std::string("m_filter_pcre: read configuration from ")+filterfile);
  64
  65                 filters.clear();
  66                 for (int index = 0; index < MyConf->Enumerate("keyword"); index++)
  67                 {
  68                         std::string pattern = MyConf->ReadValue("keyword","pattern",index);
  69                         re = pcre_compile(pattern.c_str(),0,&error,&erroffset,NULL);
  70                         if (!re)
  71                         {
  72                                 log(DEFAULT,"Error in regular expression: %s at offset %d: %s\n", pattern.c_str(), erroffset, error);
  73                                 log(DEFAULT,"Regular expression %s not loaded.", pattern.c_str());
  74                         }
  75                         else
  76                         {
  77                                 filters.push_back(re);
  78                                 log(DEFAULT,"Regular expression %s loaded.", pattern.c_str());
  79                         }
  80                 }
  81
  82         }
  83
  84         virtual ~ModuleFilterPCRE()
  85         {
  86                 delete MyConf;
  87                 delete Conf;
  88         }
  89
  90         void Implements(char* List)
  91         {
  92                 List[I_OnUserPreMessage] = List[I_OnUserPreNotice] = List[I_OnRehash] = 1;
  93         }
  94
  95         // format of a config entry is <keyword pattern="^regexp$" reason="Some reason here" action="kill/block">
  96
  97         virtual int OnUserPreMessage(userrec* user,void* dest,int target_type, std::string &text, char status)
  98         {
  99                 return OnUserPreNotice(user,dest,target_type,text,status);
 100         }
 101
 102         virtual int OnUserPreNotice(userrec* user,void* dest,int target_type, std::string &text, char status)
 103         {
 104                 for (unsigned int index = 0; index < filters.size(); index++)
 105                 {
 106                         if (pcre_exec(filters[index],NULL,text.c_str(),text.length(),0,0,NULL,0) > -1)
 107                         {
 108                                 std::string target = "";
 109                                 std::string reason = MyConf->ReadValue("keyword","reason",index);
 110                                 std::string do_action = MyConf->ReadValue("keyword","action",index);
 111
 112                                 if (do_action == "")
 113                                         do_action = "none";
 114
 115                                 if (target_type == TYPE_USER)
 116                                 {
 117                                         userrec* t = (userrec*)dest;
 118                                         target = std::string(t->nick);
 119                                 }
 120                                 else if (target_type == TYPE_CHANNEL)
 121                                 {
 122                                         chanrec* t = (chanrec*)dest;
 123                                         target = std::string(t->name);
 124                                 }
 125                                 if (do_action == "block")
 126                                 {
 127                                         Srv->SendOpers(std::string("Filter: ")+std::string(user->nick)+
 128                                                         std::string(" had their notice filtered, target was ")+
 129                                                         target+": "+reason);
 130                                         Srv->SendTo(NULL,user,"NOTICE "+std::string(user->nick)+
 131                                                         " :Your notice has been filtered and opers notified: "+reason);
 132                                 }
 133                                 Srv->Log(DEFAULT,std::string("Filter: ")+std::string(user->nick)+
 134                                                 std::string(" had their notice filtered, target was ")+
 135                                                 target+": "+reason+" Action: "+do_action);
 136
 137                                 if (do_action == "kill")
 138                                 {
 139                                         Srv->QuitUser(user,reason);
 140                                 }
 141                                 return 1;
 142                         }
 143                 }
 144                 return 0;
 145         }
 146
 147         virtual void OnRehash(std::string parameter)
 148         {
 149                 // reload our config file on rehash - we must destroy and re-allocate the classes
 150                 // to call the constructor again and re-read our data.
 151                 delete Conf;
 152                 delete MyConf;
 153                 Conf = new ConfigReader;
 154                 std::string filterfile = Conf->ReadValue("filter","file",0);
 155                 // this automatically re-reads the configuration file into the class
 156                 MyConf = new ConfigReader(filterfile);
 157                 if ((filterfile == "") || (!MyConf->Verify()))
 158                 {
 159                         // bail if the user forgot to create a config file
 160                         printf("Error, could not find <filter file=\"\"> definition in your config file!");
 161                         log(DEFAULT,"Error, could not find <filter file=\"\"> definition in your config file!");
 162                         return;
 163                 }
 164                 Srv->Log(DEFAULT,std::string("m_filter_pcre: read configuration from ")+filterfile);
 165
 166                 filters.clear();
 167                 for (int index = 0; index < MyConf->Enumerate("keyword"); index++)
 168                 {
 169                         std::string pattern = MyConf->ReadValue("keyword","pattern",index);
 170                         re = pcre_compile(pattern.c_str(),0,&error,&erroffset,NULL);
 171                         if (!re)
 172                         {
 173                                 log(DEFAULT,"Error in regular expression: %s at offset %d: %s\n", pattern.c_str(), erroffset, error);
 174                                 log(DEFAULT,"Regular expression %s not loaded.", pattern.c_str());
 175                         }
 176                         else
 177                         {
 178                                 filters.push_back(re);
 179                                 log(DEFAULT,"Regular expression %s loaded.", pattern.c_str());
 180                         }
 181                 }
 182
 183         }
 184
 185         virtual Version GetVersion()
 186         {
 187                 // This is version 2 because version 1.x is the unreleased unrealircd module
 188                 return Version(3,0,0,0,VF_VENDOR);
 189         }
 190
 191 };
 192
 193 // stuff down here is the module-factory stuff. For basic modules you can ignore this.
 194
 195 class ModuleFilterPCREFactory : public ModuleFactory
 196 {
 197  public:
 198         ModuleFilterPCREFactory()
 199         {
 200         }
 201
 202         ~ModuleFilterPCREFactory()
 203         {
 204         }
 205
 206         virtual Module * CreateModule(Server* Me)
 207         {
 208                 return new ModuleFilterPCRE(Me);
 209         }
 210
 211 };
 212
 213
 214 extern "C" void * init_module( void )
 215 {
 216         return new ModuleFilterPCREFactory;
 217 }
 218