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         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)
  98         {
  99                 for (unsigned int index = 0; index < filters.size(); index++)
 100                 {
 101                         if (pcre_exec(filters[index],NULL,text.c_str(),text.length(),0,0,NULL,0) > -1)
 102                         {
 103                                 std::string target = "";
 104                                 std::string reason = MyConf->ReadValue("keyword","reason",index);
 105                                 std::string do_action = MyConf->ReadValue("keyword","action",index);
 106
 107                                 if (do_action == "")
 108                                         do_action = "none";
 109
 110                                 if (target_type == TYPE_USER)
 111                                 {
 112                                         userrec* t = (userrec*)dest;
 113                                         target = std::string(t->nick);
 114                                 }
 115                                 else if (target_type == TYPE_CHANNEL)
 116                                 {
 117                                         chanrec* t = (chanrec*)dest;
 118                                         target = std::string(t->name);
 119                                 }
 120                                 if (do_action == "block")
 121                                 {
 122                                         Srv->SendOpers(std::string("FilterPCRE: ")+std::string(user->nick)+
 123                                                         std::string(" had their message filtered, target was ")+
 124                                                         target+": "+reason);
 125                                         // this form of SendTo (with the source as NuLL) sends a server notice
 126                                         Srv->SendTo(NULL,user,"NOTICE "+std::string(user->nick)+
 127                                                         " :Your message has been filtered and opers notified: "+reason);
 128                                 }
 129
 130                                 Srv->Log(DEFAULT,std::string("Filter: ")+std::string(user->nick)+
 131                                                 std::string(" had their message filtered, target was ")+
 132                                                 target+": "+reason+" Action: "+do_action);
 133
 134                                 if (do_action == "kill")
 135                                 {
 136                                         Srv->QuitUser(user,reason);
 137                                 }
 138                                 return 1;
 139                         }
 140                 }
 141                 return 0;
 142         }
 143
 144         virtual int OnUserPreNotice(userrec* user,void* dest,int target_type, std::string &text)
 145         {
 146                 for (unsigned int index = 0; index < filters.size(); index++)
 147                 {
 148                         if (pcre_exec(filters[index],NULL,text.c_str(),text.length(),0,0,NULL,0) > -1)
 149                         {
 150                                 std::string target = "";
 151                                 std::string reason = MyConf->ReadValue("keyword","reason",index);
 152                                 std::string do_action = MyConf->ReadValue("keyword","action",index);
 153
 154                                 if (do_action == "")
 155                                         do_action = "none";
 156
 157                                 if (target_type == TYPE_USER)
 158                                 {
 159                                         userrec* t = (userrec*)dest;
 160                                         target = std::string(t->nick);
 161                                 }
 162                                 else if (target_type == TYPE_CHANNEL)
 163                                 {
 164                                         chanrec* t = (chanrec*)dest;
 165                                         target = std::string(t->name);
 166                                 }
 167                                 if (do_action == "block")
 168                                 {
 169                                         Srv->SendOpers(std::string("Filter: ")+std::string(user->nick)+
 170                                                         std::string(" had their notice filtered, target was ")+
 171                                                         target+": "+reason);
 172                                         Srv->SendTo(NULL,user,"NOTICE "+std::string(user->nick)+
 173                                                         " :Your notice has been filtered and opers notified: "+reason);
 174                                 }
 175                                 Srv->Log(DEFAULT,std::string("Filter: ")+std::string(user->nick)+
 176                                                 std::string(" had their notice filtered, target was ")+
 177                                                 target+": "+reason+" Action: "+do_action);
 178
 179                                 if (do_action == "kill")
 180                                 {
 181                                         Srv->QuitUser(user,reason);
 182                                 }
 183                                 return 1;
 184                         }
 185                 }
 186                 return 0;
 187         }
 188
 189         virtual void OnRehash(std::string parameter)
 190         {
 191                 // reload our config file on rehash - we must destroy and re-allocate the classes
 192                 // to call the constructor again and re-read our data.
 193                 delete Conf;
 194                 delete MyConf;
 195                 Conf = new ConfigReader;
 196                 std::string filterfile = Conf->ReadValue("filter","file",0);
 197                 // this automatically re-reads the configuration file into the class
 198                 MyConf = new ConfigReader(filterfile);
 199                 if ((filterfile == "") || (!MyConf->Verify()))
 200                 {
 201                         // bail if the user forgot to create a config file
 202                         printf("Error, could not find <filter file=\"\"> definition in your config file!");
 203                         log(DEFAULT,"Error, could not find <filter file=\"\"> definition in your config file!");
 204                         return;
 205                 }
 206                 Srv->Log(DEFAULT,std::string("m_filter_pcre: read configuration from ")+filterfile);
 207
 208                 filters.clear();
 209                 for (int index = 0; index < MyConf->Enumerate("keyword"); index++)
 210                 {
 211                         std::string pattern = MyConf->ReadValue("keyword","pattern",index);
 212                         re = pcre_compile(pattern.c_str(),0,&error,&erroffset,NULL);
 213                         if (!re)
 214                         {
 215                                 log(DEFAULT,"Error in regular expression: %s at offset %d: %s\n", pattern.c_str(), erroffset, error);
 216                                 log(DEFAULT,"Regular expression %s not loaded.", pattern.c_str());
 217                         }
 218                         else
 219                         {
 220                                 filters.push_back(re);
 221                                 log(DEFAULT,"Regular expression %s loaded.", pattern.c_str());
 222                         }
 223                 }
 224
 225         }
 226
 227         virtual Version GetVersion()
 228         {
 229                 // This is version 2 because version 1.x is the unreleased unrealircd module
 230                 return Version(3,0,0,0,VF_VENDOR);
 231         }
 232
 233 };
 234
 235 // stuff down here is the module-factory stuff. For basic modules you can ignore this.
 236
 237 class ModuleFilterPCREFactory : public ModuleFactory
 238 {
 239  public:
 240         ModuleFilterPCREFactory()
 241         {
 242         }
 243
 244         ~ModuleFilterPCREFactory()
 245         {
 246         }
 247
 248         virtual Module * CreateModule(Server* Me)
 249         {
 250                 return new ModuleFilterPCRE(Me);
 251         }
 252
 253 };
 254
 255
 256 extern "C" void * init_module( void )
 257 {
 258         return new ModuleFilterPCREFactory;
 259 }
 260