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 // Message and notice filtering using regex patterns
  18 // a module based on the original work done by Craig Edwards in 2003
  19 // for the chatspike network.
  20
  21 #include <stdio.h>
  22 #include <string>
  23 #include <pcre.h>
  24 #include "users.h"
  25 #include "channels.h"
  26 #include "modules.h"
  27
  28 /* $ModDesc: m_filter with regexps */
  29 /* $CompileFlags: -I/usr/local/include -L/usr/local/lib -lpcre */
  30
  31 class ModuleFilterPCRE : public Module
  32 {
  33         Server *Srv;
  34         ConfigReader *Conf, *MyConf;
  35         std::vector<pcre*> filters;
  36         pcre *re;
  37         const char *error;
  38         int erroffset;
  39
  40  public:
  41         ModuleFilterPCRE()
  42         {
  43                 // read the configuration file on startup.
  44                 // it is perfectly valid to set <FilterPCRE file> to the value of the
  45                 // main config file, then append your <keyword> tags to the bottom
  46                 // of the main config... but rather messy. That's why the capability
  47                 // of using a seperate config file is provided.
  48                 Srv = new Server;
  49                 Conf = new ConfigReader;
  50                 std::string filterfile = Conf->ReadValue("filter","file",0);
  51                 MyConf = new ConfigReader(filterfile);
  52                 if ((filterfile == "") || (!MyConf->Verify()))
  53                 {
  54                         printf("Error, could not find <filter file=\"\"> definition in your config file!");
  55                         log(DEFAULT,"Error, could not find <filter file=\"\"> definition in your config file!");
  56                         return;
  57                 }
  58                 Srv->Log(DEFAULT,std::string("m_filter_pcre: read configuration from ")+filterfile);
  59
  60                 filters.clear();
  61                 for (int index = 0; index < MyConf->Enumerate("keyword"); index++)
  62                 {
  63                         std::string pattern = MyConf->ReadValue("keyword","pattern",index);
  64                         re = pcre_compile(pattern.c_str(),0,&error,&erroffset,NULL);
  65                         if (!re)
  66                         {
  67                                 log(DEFAULT,"Error in regular expression: %s at offset %d: %s\n", pattern.c_str(), erroffset, error);
  68                                 log(DEFAULT,"Regular expression %s not loaded.", pattern.c_str());
  69                         }
  70                         else
  71                         {
  72                                 filters.push_back(re);
  73                                 log(DEFAULT,"Regular expression %s loaded.", pattern.c_str());
  74                         }
  75                 }
  76
  77         }
  78
  79         virtual ~ModuleFilterPCRE()
  80         {
  81                 delete Srv;
  82                 delete MyConf;
  83                 delete Conf;
  84         }
  85
  86         // format of a config entry is <keyword pattern="^regexp$" reason="Some reason here" action="kill/block">
  87
  88         virtual int OnUserPreMessage(userrec* user,void* dest,int target_type, std::string &text)
  89         {
  90                 for (int index = 0; index < filters.size(); index++)
  91                 {
  92                         log(DEFAULT,"Match regexp %d: returned %d",index,pcre_exec(filters[index],NULL,text.c_str(),text.length(),0,0,NULL,0));
  93                         if (pcre_exec(filters[index],NULL,text.c_str(),text.length(),0,0,NULL,0) > -1)
  94                         {
  95                                 std::string target = "";
  96                                 std::string reason = MyConf->ReadValue("keyword","reason",index);
  97                                 std::string do_action = MyConf->ReadValue("keyword","action",index);
  98
  99                                 if (do_action == "")
 100                                         do_action = "none";
 101
 102                                 if (target_type == TYPE_USER)
 103                                 {
 104                                         userrec* t = (userrec*)dest;
 105                                         target = std::string(t->nick);
 106                                 }
 107                                 else if (target_type == TYPE_CHANNEL)
 108                                 {
 109                                         chanrec* t = (chanrec*)dest;
 110                                         target = std::string(t->name);
 111                                 }
 112                                 if (do_action == "block")
 113                                 {
 114                                         Srv->SendOpers(std::string("FilterPCRE: ")+std::string(user->nick)+
 115                                                         std::string(" had their message filtered, target was ")+
 116                                                         target+": "+reason);
 117                                         // this form of SendTo (with the source as NuLL) sends a server notice
 118                                         Srv->SendTo(NULL,user,"NOTICE "+std::string(user->nick)+
 119                                                         " :Your message has been filtered and opers notified: "+reason);
 120                                 }
 121
 122                                 Srv->Log(DEFAULT,std::string("Filter: ")+std::string(user->nick)+
 123                                                 std::string(" had their message filtered, target was ")+
 124                                                 target+": "+reason+" Action: "+do_action);
 125
 126                                 if (do_action == "kill")
 127                                 {
 128                                         Srv->QuitUser(user,reason);
 129                                 }
 130                                 return 1;
 131                         }
 132                 }
 133                 return 0;
 134         }
 135
 136         virtual int OnUserPreNotice(userrec* user,void* dest,int target_type, std::string &text)
 137         {
 138                 for (int index = 0; index < filters.size(); index++)
 139                 {
 140                         if (pcre_exec(filters[index],NULL,text.c_str(),text.length(),0,0,NULL,0) > -1)
 141                         {
 142                                 std::string target = "";
 143                                 std::string reason = MyConf->ReadValue("keyword","reason",index);
 144                                 std::string do_action = MyConf->ReadValue("keyword","action",index);
 145
 146                                 if (do_action == "")
 147                                         do_action = "none";
 148
 149                                 if (target_type == TYPE_USER)
 150                                 {
 151                                         userrec* t = (userrec*)dest;
 152                                         target = std::string(t->nick);
 153                                 }
 154                                 else if (target_type == TYPE_CHANNEL)
 155                                 {
 156                                         chanrec* t = (chanrec*)dest;
 157                                         target = std::string(t->name);
 158                                 }
 159                                 if (do_action == "block")
 160                                 {
 161                                         Srv->SendOpers(std::string("FilterPCRE: ")+std::string(user->nick)+
 162                                                         std::string(" had their notice filtered, target was ")+
 163                                                         target+": "+reason);
 164                                         Srv->SendTo(NULL,user,"NOTICE "+std::string(user->nick)+
 165                                                         " :Your notice has been filtered and opers notified: "+reason);
 166                                 }
 167                                 Srv->Log(DEFAULT,std::string("FilterPCRE: ")+std::string(user->nick)+
 168                                                 std::string(" had their notice filtered, target was ")+
 169                                                 target+": "+reason+" Action: "+do_action);
 170
 171                                 if (do_action == "kill")
 172                                 {
 173                                         Srv->QuitUser(user,reason);
 174                                 }
 175                                 return 1;
 176                         }
 177                 }
 178                 return 0;
 179         }
 180
 181         virtual void OnRehash()
 182         {
 183                 // reload our config file on rehash - we must destroy and re-allocate the classes
 184                 // to call the constructor again and re-read our data.
 185                 delete Conf;
 186                 delete MyConf;
 187                 Conf = new ConfigReader;
 188                 std::string filterfile = Conf->ReadValue("filter","file",0);
 189                 // this automatically re-reads the configuration file into the class
 190                 MyConf = new ConfigReader(filterfile);
 191                 if ((filterfile == "") || (!MyConf->Verify()))
 192                 {
 193                         // bail if the user forgot to create a config file
 194                         printf("Error, could not find <filter file=\"\"> definition in your config file!");
 195                         log(DEFAULT,"Error, could not find <filter file=\"\"> definition in your config file!");
 196                         return;
 197                 }
 198                 Srv->Log(DEFAULT,std::string("m_Filter_pcre: read configuration from ")+filterfile);
 199
 200                 filters.clear();
 201                 for (int index = 0; index < MyConf->Enumerate("keyword"); index++)
 202                 {
 203                         std::string pattern = MyConf->ReadValue("keyword","pattern",index);
 204                         re = pcre_compile(pattern.c_str(),0,&error,&erroffset,NULL);
 205                         if (!re)
 206                         {
 207                                 log(DEFAULT,"Error in regular expression: %s at offset %d: %s\n", pattern.c_str(), erroffset, error);
 208                                 log(DEFAULT,"Regular expression %s not loaded.", pattern.c_str());
 209                         }
 210                         else
 211                         {
 212                                 filters.push_back(re);
 213                                 log(DEFAULT,"Regular expression %s loaded.", pattern.c_str());
 214                         }
 215                 }
 216
 217         }
 218
 219         virtual Version GetVersion()
 220         {
 221                 // This is version 2 because version 1.x is the unreleased unrealircd module
 222                 return Version(3,0,0,0,VF_VENDOR);
 223         }
 224
 225 };
 226
 227 // stuff down here is the module-factory stuff. For basic modules you can ignore this.
 228
 229 class ModuleFilterPCREFactory : public ModuleFactory
 230 {
 231  public:
 232         ModuleFilterPCREFactory()
 233         {
 234         }
 235
 236         ~ModuleFilterPCREFactory()
 237         {
 238         }
 239
 240         virtual Module * CreateModule()
 241         {
 242                 return new ModuleFilterPCRE;
 243         }
 244
 245 };
 246
 247
 248 extern "C" void * init_module( void )
 249 {
 250         return new ModuleFilterPCREFactory;
 251 }
 252