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 -L/usr/local/lib -lpcre */
  33
  34 class ModuleFilterPCRE : public Module
  35 {
  36         Server *Srv;
  37         ConfigReader *Conf, *MyConf;
  38         std::vector<pcre*> filters;
  39         pcre *re;
  40         const char *error;
  41         int erroffset;
  42
  43  public:
  44         ModuleFilterPCRE(Server* Me)
  45                 : Module::Module(Me)
  46         {
  47                 // read the configuration file on startup.
  48                 // it is perfectly valid to set <filter file> to the value of the
  49                 // main config file, then append your <keyword> tags to the bottom
  50                 // of the main config... but rather messy. That's why the capability
  51                 // of using a seperate config file is provided.
  52                 Srv = Me;
  53                 Conf = new ConfigReader;
  54                 std::string filterfile = Conf->ReadValue("filter","file",0);
  55                 MyConf = new ConfigReader(filterfile);
  56                 if ((filterfile == "") || (!MyConf->Verify()))
  57                 {
  58                         printf("Error, could not find <filter file=\"\"> definition in your config file!");
  59                         log(DEFAULT,"Error, could not find <filter file=\"\"> definition in your config file!");
  60                         return;
  61                 }
  62                 Srv->Log(DEFAULT,std::string("m_filter_pcre: read configuration from ")+filterfile);
  63
  64                 filters.clear();
  65                 for (int index = 0; index < MyConf->Enumerate("keyword"); index++)
  66                 {
  67                         std::string pattern = MyConf->ReadValue("keyword","pattern",index);
  68                         re = pcre_compile(pattern.c_str(),0,&error,&erroffset,NULL);
  69                         if (!re)
  70                         {
  71                                 log(DEFAULT,"Error in regular expression: %s at offset %d: %s\n", pattern.c_str(), erroffset, error);
  72                                 log(DEFAULT,"Regular expression %s not loaded.", pattern.c_str());
  73                         }
  74                         else
  75                         {
  76                                 filters.push_back(re);
  77                                 log(DEFAULT,"Regular expression %s loaded.", pattern.c_str());
  78                         }
  79                 }
  80
  81         }
  82
  83         virtual ~ModuleFilterPCRE()
  84         {
  85                 delete MyConf;
  86                 delete Conf;
  87         }
  88
  89         // format of a config entry is <keyword pattern="^regexp$" reason="Some reason here" action="kill/block">
  90
  91         virtual int OnUserPreMessage(userrec* user,void* dest,int target_type, std::string &text)
  92         {
  93                 for (unsigned int index = 0; index < filters.size(); index++)
  94                 {
  95                         if (pcre_exec(filters[index],NULL,text.c_str(),text.length(),0,0,NULL,0) > -1)
  96                         {
  97                                 std::string target = "";
  98                                 std::string reason = MyConf->ReadValue("keyword","reason",index);
  99                                 std::string do_action = MyConf->ReadValue("keyword","action",index);
 100
 101                                 if (do_action == "")
 102                                         do_action = "none";
 103
 104                                 if (target_type == TYPE_USER)
 105                                 {
 106                                         userrec* t = (userrec*)dest;
 107                                         target = std::string(t->nick);
 108                                 }
 109                                 else if (target_type == TYPE_CHANNEL)
 110                                 {
 111                                         chanrec* t = (chanrec*)dest;
 112                                         target = std::string(t->name);
 113                                 }
 114                                 if (do_action == "block")
 115                                 {
 116                                         Srv->SendOpers(std::string("FilterPCRE: ")+std::string(user->nick)+
 117                                                         std::string(" had their message filtered, target was ")+
 118                                                         target+": "+reason);
 119                                         // this form of SendTo (with the source as NuLL) sends a server notice
 120                                         Srv->SendTo(NULL,user,"NOTICE "+std::string(user->nick)+
 121                                                         " :Your message has been filtered and opers notified: "+reason);
 122                                 }
 123
 124                                 Srv->Log(DEFAULT,std::string("Filter: ")+std::string(user->nick)+
 125                                                 std::string(" had their message filtered, target was ")+
 126                                                 target+": "+reason+" Action: "+do_action);
 127
 128                                 if (do_action == "kill")
 129                                 {
 130                                         Srv->QuitUser(user,reason);
 131                                 }
 132                                 return 1;
 133                         }
 134                 }
 135                 return 0;
 136         }
 137
 138         virtual int OnUserPreNotice(userrec* user,void* dest,int target_type, std::string &text)
 139         {
 140                 for (unsigned int index = 0; index < filters.size(); index++)
 141                 {
 142                         if (pcre_exec(filters[index],NULL,text.c_str(),text.length(),0,0,NULL,0) > -1)
 143                         {
 144                                 std::string target = "";
 145                                 std::string reason = MyConf->ReadValue("keyword","reason",index);
 146                                 std::string do_action = MyConf->ReadValue("keyword","action",index);
 147
 148                                 if (do_action == "")
 149                                         do_action = "none";
 150
 151                                 if (target_type == TYPE_USER)
 152                                 {
 153                                         userrec* t = (userrec*)dest;
 154                                         target = std::string(t->nick);
 155                                 }
 156                                 else if (target_type == TYPE_CHANNEL)
 157                                 {
 158                                         chanrec* t = (chanrec*)dest;
 159                                         target = std::string(t->name);
 160                                 }
 161                                 if (do_action == "block")
 162                                 {
 163                                         Srv->SendOpers(std::string("Filter: ")+std::string(user->nick)+
 164                                                         std::string(" had their notice filtered, target was ")+
 165                                                         target+": "+reason);
 166                                         Srv->SendTo(NULL,user,"NOTICE "+std::string(user->nick)+
 167                                                         " :Your notice has been filtered and opers notified: "+reason);
 168                                 }
 169                                 Srv->Log(DEFAULT,std::string("Filter: ")+std::string(user->nick)+
 170                                                 std::string(" had their notice filtered, target was ")+
 171                                                 target+": "+reason+" Action: "+do_action);
 172
 173                                 if (do_action == "kill")
 174                                 {
 175                                         Srv->QuitUser(user,reason);
 176                                 }
 177                                 return 1;
 178                         }
 179                 }
 180                 return 0;
 181         }
 182
 183         virtual void OnRehash(std::string parameter)
 184         {
 185                 // reload our config file on rehash - we must destroy and re-allocate the classes
 186                 // to call the constructor again and re-read our data.
 187                 delete Conf;
 188                 delete MyConf;
 189                 Conf = new ConfigReader;
 190                 std::string filterfile = Conf->ReadValue("filter","file",0);
 191                 // this automatically re-reads the configuration file into the class
 192                 MyConf = new ConfigReader(filterfile);
 193                 if ((filterfile == "") || (!MyConf->Verify()))
 194                 {
 195                         // bail if the user forgot to create a config file
 196                         printf("Error, could not find <filter file=\"\"> definition in your config file!");
 197                         log(DEFAULT,"Error, could not find <filter file=\"\"> definition in your config file!");
 198                         return;
 199                 }
 200                 Srv->Log(DEFAULT,std::string("m_filter_pcre: read configuration from ")+filterfile);
 201
 202                 filters.clear();
 203                 for (int index = 0; index < MyConf->Enumerate("keyword"); index++)
 204                 {
 205                         std::string pattern = MyConf->ReadValue("keyword","pattern",index);
 206                         re = pcre_compile(pattern.c_str(),0,&error,&erroffset,NULL);
 207                         if (!re)
 208                         {
 209                                 log(DEFAULT,"Error in regular expression: %s at offset %d: %s\n", pattern.c_str(), erroffset, error);
 210                                 log(DEFAULT,"Regular expression %s not loaded.", pattern.c_str());
 211                         }
 212                         else
 213                         {
 214                                 filters.push_back(re);
 215                                 log(DEFAULT,"Regular expression %s loaded.", pattern.c_str());
 216                         }
 217                 }
 218
 219         }
 220
 221         virtual Version GetVersion()
 222         {
 223                 // This is version 2 because version 1.x is the unreleased unrealircd module
 224                 return Version(3,0,0,0,VF_VENDOR);
 225         }
 226
 227 };
 228
 229 // stuff down here is the module-factory stuff. For basic modules you can ignore this.
 230
 231 class ModuleFilterPCREFactory : public ModuleFactory
 232 {
 233  public:
 234         ModuleFilterPCREFactory()
 235         {
 236         }
 237
 238         ~ModuleFilterPCREFactory()
 239         {
 240         }
 241
 242         virtual Module * CreateModule(Server* Me)
 243         {
 244                 return new ModuleFilterPCRE(Me);
 245         }
 246
 247 };
 248
 249
 250 extern "C" void * init_module( void )
 251 {
 252         return new ModuleFilterPCREFactory;
 253 }
 254