src/modules/m_ident.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd is copyright (C) 2002-2006 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 #include <stdio.h>
  20 #include <string>
  21 #include "users.h"
  22 #include "channels.h"
  23 #include "modules.h"
  24 #include "inspircd.h"
  25
  26 extern InspIRCd* ServerInstance;
  27
  28 extern userrec* fd_ref_table[MAX_DESCRIPTORS];
  29
  30 /* $ModDesc: Provides support for RFC 1413 ident lookups */
  31
  32 // Version 1.5.0.0 - Updated to use InspSocket, faster and neater.
  33
  34 class RFC1413 : public InspSocket
  35 {
  36  protected:
  37         Server* Srv;             // Server* class used for core communications
  38         insp_sockaddr sock_us;   // our port number
  39         insp_sockaddr sock_them; // their port number
  40         socklen_t uslen;         // length of our port number
  41         socklen_t themlen;       // length of their port number
  42         char ident_request[128]; // buffer used to make up the request string
  43  public:
  44
  45         userrec* u;              // user record that the lookup is associated with
  46         int ufd;
  47
  48         RFC1413(InspIRCd* SI, userrec* user, int maxtime, Server* S) : InspSocket(SI, user->GetIPString(), 113, false, maxtime), Srv(S), u(user), ufd(user->fd)
  49         {
  50                 log(DEBUG,"Ident: associated.");
  51         }
  52
  53         virtual void OnTimeout()
  54         {
  55                 // When we timeout, the connection failed within the allowed timeframe,
  56                 // so we just display a notice, and tidy off the ident_data.
  57                 if (u && (fd_ref_table[ufd] == u))
  58                 {
  59                         u->Shrink("ident_data");
  60                         u->WriteServ("NOTICE "+std::string(u->nick)+" :*** Could not find your ident, using "+std::string(u->ident)+" instead.");
  61                 }
  62         }
  63
  64         virtual bool OnDataReady()
  65         {
  66                 char* ibuf = this->Read();
  67                 if (ibuf)
  68                 {
  69                         char* savept;
  70                         char* section = strtok_r(ibuf,":",&savept);
  71                         while (section)
  72                         {
  73                                 if (strstr(section,"USERID"))
  74                                 {
  75                                         section = strtok_r(NULL,":",&savept);
  76                                         if (section)
  77                                         {
  78                                                 // ID type, usually UNIX or OTHER... we dont want it, so read the next token
  79                                                 section = strtok_r(NULL,":",&savept);
  80                                                 if (section)
  81                                                 {
  82                                                         while (*section == ' ') section++; // strip leading spaces
  83                                                         for (char* j = section; *j; j++)
  84                                                         if ((*j < 33) || (*j > 126))
  85                                                                 *j = '\0'; // truncate at invalid chars
  86                                                         if (*section)
  87                                                         {
  88                                                                 if (u && (fd_ref_table[ufd] == u))
  89                                                                 {
  90                                                                         strlcpy(u->ident,section,IDENTMAX);
  91                                                                         log(DEBUG,"IDENT SET: "+std::string(u->ident));
  92                                                                         u->WriteServ("NOTICE "+std::string(u->nick)+" :*** Found your ident: "+std::string(u->ident));
  93                                                                 }
  94                                                         }
  95                                                         return false;
  96                                                 }
  97                                         }
  98                                 }
  99                                 section = strtok_r(NULL,":",&savept);
 100                         }
 101                 }
 102                 return false;
 103         }
 104
 105         virtual void OnClose()
 106         {
 107                 // tidy up after ourselves when the connection is done.
 108                 // We receive this event straight after a timeout, too.
 109                 //
 110                 //
 111                 // OK, now listen up. The weird looking check here is
 112                 // REQUIRED. Don't try and optimize it away.
 113                 //
 114                 // When a socket is closed, it is not immediately removed
 115                 // from the socket list, there can be a short delay
 116                 // before it is culled from the list. This means that
 117                 // without this check, there is a chance that a user
 118                 // may not exist when we come to ::Shrink them, which
 119                 // results in a segfault. The value of "u" may not
 120                 // always be NULL at this point, so, what we do is
 121                 // check against the fd_ref_table, to see if (1) the user
 122                 // exists, and (2) its the SAME user, on the same file
 123                 // descriptor that they were when the lookup began.
 124                 //
 125                 // Fixes issue reported by webs, 7 Jun 2006
 126                 if (u && (fd_ref_table[ufd] == u))
 127                 {
 128                         u->Shrink("ident_data");
 129                 }
 130         }
 131
 132         virtual void OnError(InspSocketError e)
 133         {
 134                 if (u && (fd_ref_table[ufd] == u))
 135                 {
 136                         u->Shrink("ident_data");
 137                 }
 138         }
 139
 140         virtual bool OnConnected()
 141         {
 142                 if (u && (fd_ref_table[ufd] == u))
 143                 {
 144                         uslen = sizeof(sock_us);
 145                         themlen = sizeof(sock_them);
 146                         if ((getsockname(this->u->fd,(sockaddr*)&sock_us,&uslen) || getpeername(this->u->fd, (sockaddr*)&sock_them, &themlen)))
 147                         {
 148                                 log(DEBUG,"Ident: failed to get socket names, bailing");
 149                                 return false;
 150                         }
 151                         else
 152                         {
 153                                 // send the request in the following format: theirsocket,oursocket
 154 #ifdef IPV6
 155                                 snprintf(ident_request,127,"%d,%d\r\n",ntohs(sock_them.sin6_port),ntohs(sock_us.sin6_port));
 156 #else
 157                                 snprintf(ident_request,127,"%d,%d\r\n",ntohs(sock_them.sin_port),ntohs(sock_us.sin_port));
 158 #endif
 159                                 this->Write(ident_request);
 160                                 log(DEBUG,"Sent ident request, waiting for reply");
 161                                 return true;
 162                         }
 163                 }
 164                 else
 165                 {
 166                         return true;
 167                 }
 168         }
 169 };
 170
 171 class ModuleIdent : public Module
 172 {
 173
 174         ConfigReader* Conf;
 175         Server* Srv;
 176         int IdentTimeout;
 177
 178  public:
 179         void ReadSettings()
 180         {
 181                 Conf = new ConfigReader;
 182                 IdentTimeout = Conf->ReadInteger("ident","timeout",0,true);
 183                 if (!IdentTimeout)
 184                         IdentTimeout = 1;
 185                 DELETE(Conf);
 186         }
 187
 188         ModuleIdent(Server* Me)
 189                 : Module::Module(Me)
 190         {
 191                 Srv = Me;
 192                 ReadSettings();
 193         }
 194
 195         void Implements(char* List)
 196         {
 197                 List[I_OnCleanup] = List[I_OnRehash] = List[I_OnUserRegister] = List[I_OnCheckReady] = List[I_OnUserDisconnect] = 1;
 198         }
 199
 200         virtual void OnRehash(const std::string &parameter)
 201         {
 202                 ReadSettings();
 203         }
 204
 205         virtual void OnUserRegister(userrec* user)
 206         {
 207                 /*
 208                  * when the new user connects, before they authenticate with USER/NICK/PASS, we do
 209                  * their ident lookup. We do this by instantiating an object of type RFC1413, which
 210                  * is derived from InspSocket, and inserting it into the socket engine using the
 211                  * Server::AddSocket() call.
 212                  */
 213                 user->WriteServ("NOTICE "+std::string(user->nick)+" :*** Looking up your ident...");
 214                 RFC1413* ident = new RFC1413(ServerInstance, user, IdentTimeout, Srv);
 215                 if (ident->GetState() != I_ERROR)
 216                 {
 217                         user->Extend("ident_data", (char*)ident);
 218                         Srv->AddSocket(ident);
 219                 }
 220                 else
 221                 {
 222                         user->WriteServ("NOTICE "+std::string(user->nick)+" :*** Could not find your ident, using "+std::string(user->ident)+" instead.");
 223                         DELETE(ident);
 224                 }
 225         }
 226
 227         virtual bool OnCheckReady(userrec* user)
 228         {
 229                 /*
 230                  * The socket engine will clean up their ident request for us when it completes,
 231                  * either due to timeout or due to closing, so, we just hold them until they dont
 232                  * have an ident field any more.
 233                  */
 234                 RFC1413* ident;
 235                 return (!user->GetExt("ident_data", ident));
 236         }
 237
 238         virtual void OnCleanup(int target_type, void* item)
 239         {
 240                 if (target_type == TYPE_USER)
 241                 {
 242                         userrec* user = (userrec*)item;
 243                         RFC1413* ident;
 244                         if (user->GetExt("ident_data", ident))
 245                         {
 246                                 // FIX: If the user record is deleted, the socket wont be removed
 247                                 // immediately so there is chance of the socket trying to write to
 248                                 // a user which has now vanished! To prevent this, set ident::u
 249                                 // to NULL and check it so that we dont write users who have gone away.
 250                                 ident->u = NULL;
 251                                 Srv->RemoveSocket(ident);
 252                         }
 253                 }
 254         }
 255
 256         virtual void OnUserDisconnect(userrec* user)
 257         {
 258                 /*
 259                  * when the user quits tidy up any ident lookup they have pending to keep things tidy.
 260                  * When we call RemoveSocket, the abstractions tied into the system evnetually work their
 261                  * way to RFC1459::OnClose(), which shrinks off the ident_data for us, so we dont need
 262                  * to do it here. If we don't tidy this up, there may still be lingering idents for users
 263                  * who have quit, as class RFC1459 is only loosely bound to userrec* via a pair of pointers
 264                  * and this would leave at least one of the invalid ;)
 265                  */
 266                 RFC1413* ident;
 267                 if (user->GetExt("ident_data", ident))
 268                 {
 269                         ident->u = NULL;
 270                         Srv->RemoveSocket(ident);
 271                 }
 272         }
 273
 274         virtual ~ModuleIdent()
 275         {
 276         }
 277
 278         virtual Version GetVersion()
 279         {
 280                 return Version(1,5,0,0,VF_VENDOR);
 281         }
 282
 283 };
 284
 285 class ModuleIdentFactory : public ModuleFactory
 286 {
 287  public:
 288         ModuleIdentFactory()
 289         {
 290         }
 291
 292         ~ModuleIdentFactory()
 293         {
 294         }
 295
 296         virtual Module * CreateModule(Server* Me)
 297         {
 298                 return new ModuleIdent(Me);
 299         }
 300
 301 };
 302
 303
 304 extern "C" void * init_module( void )
 305 {
 306         return new ModuleIdentFactory;
 307 }
 308