src/modules/extra/m_filter_pcre.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  Inspire 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         // format of a config entry is <keyword pattern="^regexp$" reason="Some reason here" action="kill/block">
  91
  92         virtual int OnUserPreMessage(userrec* user,void* dest,int target_type, std::string &text)
  93         {
  94                 for (unsigned int index = 0; index < filters.size(); index++)
  95                 {
  96                         if (pcre_exec(filters[index],NULL,text.c_str(),text.length(),0,0,NULL,0) > -1)
  97                         {
  98                                 std::string target = "";
  99                                 std::string reason = MyConf->ReadValue("keyword","reason",index);
 100                                 std::string do_action = MyConf->ReadValue("keyword","action",index);
 101
 102                                 if (do_action == "")
 103                                         do_action = "none";
 104
 105                                 if (target_type == TYPE_USER)
 106                                 {
 107                                         userrec* t = (userrec*)dest;
 108                                         target = std::string(t->nick);
 109                                 }
 110                                 else if (target_type == TYPE_CHANNEL)
 111                                 {
 112                                         chanrec* t = (chanrec*)dest;
 113                                         target = std::string(t->name);
 114                                 }
 115                                 if (do_action == "block")
 116                                 {
 117                                         Srv->SendOpers(std::string("FilterPCRE: ")+std::string(user->nick)+
 118                                                         std::string(" had their message filtered, target was ")+
 119                                                         target+": "+reason);
 120                                         // this form of SendTo (with the source as NuLL) sends a server notice
 121                                         Srv->SendTo(NULL,user,"NOTICE "+std::string(user->nick)+
 122                                                         " :Your message has been filtered and opers notified: "+reason);
 123                                 }
 124
 125                                 Srv->Log(DEFAULT,std::string("Filter: ")+std::string(user->nick)+
 126                                                 std::string(" had their message filtered, target was ")+
 127                                                 target+": "+reason+" Action: "+do_action);
 128
 129                                 if (do_action == "kill")
 130                                 {
 131                                         Srv->QuitUser(user,reason);
 132                                 }
 133                                 return 1;
 134                         }
 135                 }
 136                 return 0;
 137         }
 138
 139         virtual int OnUserPreNotice(userrec* user,void* dest,int target_type, std::string &text)
 140         {
 141                 for (unsigned int index = 0; index < filters.size(); index++)
 142                 {
 143                         if (pcre_exec(filters[index],NULL,text.c_str(),text.length(),0,0,NULL,0) > -1)
 144                         {
 145                                 std::string target = "";
 146                                 std::string reason = MyConf->ReadValue("keyword","reason",index);
 147                                 std::string do_action = MyConf->ReadValue("keyword","action",index);
 148
 149                                 if (do_action == "")
 150                                         do_action = "none";
 151
 152                                 if (target_type == TYPE_USER)
 153                                 {
 154                                         userrec* t = (userrec*)dest;
 155                                         target = std::string(t->nick);
 156                                 }
 157                                 else if (target_type == TYPE_CHANNEL)
 158                                 {
 159                                         chanrec* t = (chanrec*)dest;
 160                                         target = std::string(t->name);
 161                                 }
 162                                 if (do_action == "block")
 163                                 {
 164                                         Srv->SendOpers(std::string("Filter: ")+std::string(user->nick)+
 165                                                         std::string(" had their notice filtered, target was ")+
 166                                                         target+": "+reason);
 167                                         Srv->SendTo(NULL,user,"NOTICE "+std::string(user->nick)+
 168                                                         " :Your notice has been filtered and opers notified: "+reason);
 169                                 }
 170                                 Srv->Log(DEFAULT,std::string("Filter: ")+std::string(user->nick)+
 171                                                 std::string(" had their notice filtered, target was ")+
 172                                                 target+": "+reason+" Action: "+do_action);
 173
 174                                 if (do_action == "kill")
 175                                 {
 176                                         Srv->QuitUser(user,reason);
 177                                 }
 178                                 return 1;
 179                         }
 180                 }
 181                 return 0;
 182         }
 183
 184         virtual void OnRehash(std::string parameter)
 185         {
 186                 // reload our config file on rehash - we must destroy and re-allocate the classes
 187                 // to call the constructor again and re-read our data.
 188                 delete Conf;
 189                 delete MyConf;
 190                 Conf = new ConfigReader;
 191                 std::string filterfile = Conf->ReadValue("filter","file",0);
 192                 // this automatically re-reads the configuration file into the class
 193                 MyConf = new ConfigReader(filterfile);
 194                 if ((filterfile == "") || (!MyConf->Verify()))
 195                 {
 196                         // bail if the user forgot to create a config file
 197                         printf("Error, could not find <filter file=\"\"> definition in your config file!");
 198                         log(DEFAULT,"Error, could not find <filter file=\"\"> definition in your config file!");
 199                         return;
 200                 }
 201                 Srv->Log(DEFAULT,std::string("m_filter_pcre: read configuration from ")+filterfile);
 202
 203                 filters.clear();
 204                 for (int index = 0; index < MyConf->Enumerate("keyword"); index++)
 205                 {
 206                         std::string pattern = MyConf->ReadValue("keyword","pattern",index);
 207                         re = pcre_compile(pattern.c_str(),0,&error,&erroffset,NULL);
 208                         if (!re)
 209                         {
 210                                 log(DEFAULT,"Error in regular expression: %s at offset %d: %s\n", pattern.c_str(), erroffset, error);
 211                                 log(DEFAULT,"Regular expression %s not loaded.", pattern.c_str());
 212                         }
 213                         else
 214                         {
 215                                 filters.push_back(re);
 216                                 log(DEFAULT,"Regular expression %s loaded.", pattern.c_str());
 217                         }
 218                 }
 219
 220         }
 221
 222         virtual Version GetVersion()
 223         {
 224                 // This is version 2 because version 1.x is the unreleased unrealircd module
 225                 return Version(3,0,0,0,VF_VENDOR);
 226         }
 227
 228 };
 229
 230 // stuff down here is the module-factory stuff. For basic modules you can ignore this.
 231
 232 class ModuleFilterPCREFactory : public ModuleFactory
 233 {
 234  public:
 235         ModuleFilterPCREFactory()
 236         {
 237         }
 238
 239         ~ModuleFilterPCREFactory()
 240         {
 241         }
 242
 243         virtual Module * CreateModule(Server* Me)
 244         {
 245                 return new ModuleFilterPCRE(Me);
 246         }
 247
 248 };
 249
 250
 251 extern "C" void * init_module( void )
 252 {
 253         return new ModuleFilterPCREFactory;
 254 }
 255