src/modules/m_ident.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd: (C) 2002-2007 InspIRCd Development Team
   6  * See: http://www.inspircd.org/wiki/index.php/Credits
   7  *
   8  * This program is free but copyrighted software; see
   9  *            the file COPYING for details.
  10  *
  11  * ---------------------------------------------------
  12  */
  13
  14 #include <stdio.h>
  15 #include <string>
  16 #include "users.h"
  17 #include "channels.h"
  18 #include "modules.h"
  19 #include "inspircd.h"
  20
  21 /* $ModDesc: Provides support for RFC 1413 ident lookups */
  22
  23 // Version 1.5.0.0 - Updated to use InspSocket, faster and neater.
  24
  25 /** Handles RFC1413 ident connections to users
  26  */
  27 class RFC1413 : public InspSocket
  28 {
  29  protected:
  30                          // Server* class used for core communications
  31         insp_sockaddr sock_us;   // our port number
  32         insp_sockaddr sock_them; // their port number
  33         socklen_t uslen;         // length of our port number
  34         socklen_t themlen;       // length of their port number
  35         char ident_request[128]; // buffer used to make up the request string
  36  public:
  37
  38         userrec* u;              // user record that the lookup is associated with
  39         int ufd;
  40
  41         RFC1413(InspIRCd* SI, userrec* user, int maxtime) : InspSocket(SI, user->GetIPString(), 113, false, maxtime), u(user)
  42         {
  43                 ufd = user->GetFd();
  44         }
  45
  46         virtual void OnTimeout()
  47         {
  48                 // When we timeout, the connection failed within the allowed timeframe,
  49                 // so we just display a notice, and tidy off the ident_data.
  50                 if (u && (Instance->SE->GetRef(ufd) == u))
  51                 {
  52                         char newident[MAXBUF];
  53                         u->Shrink("ident_data");
  54                         u->WriteServ("NOTICE "+std::string(u->nick)+" :*** Could not find your ident, using ~"+std::string(u->ident)+" instead.");
  55                         strcpy(newident,"~");
  56                         strlcat(newident,u->ident,IDENTMAX);
  57                         strlcpy(u->ident,newident,IDENTMAX);
  58                 }
  59         }
  60
  61         virtual bool OnDataReady()
  62         {
  63                 char* ibuf = this->Read();
  64                 if (ibuf)
  65                 {
  66                         char* savept;
  67                         char* section = strtok_r(ibuf,":",&savept);
  68                         while (section)
  69                         {
  70                                 if (strstr(section,"USERID"))
  71                                 {
  72                                         section = strtok_r(NULL,":",&savept);
  73                                         if (section)
  74                                         {
  75                                                 // ID type, usually UNIX or OTHER... we dont want it, so read the next token
  76                                                 section = strtok_r(NULL,":",&savept);
  77                                                 if (section)
  78                                                 {
  79                                                         while (*section == ' ') section++; // strip leading spaces
  80                                                         for (char* j = section; *j; j++)
  81                                                         if ((*j < 33) || (*j > 126))
  82                                                                 *j = '\0'; // truncate at invalid chars
  83                                                         if (*section)
  84                                                         {
  85                                                                 if (u && (Instance->SE->GetRef(ufd) == u))
  86                                                                 {
  87                                                                         if (this->Instance->IsIdent(section))
  88                                                                         {
  89                                                                                 strlcpy(u->ident,section,IDENTMAX);
  90                                                                                 u->WriteServ("NOTICE "+std::string(u->nick)+" :*** Found your ident: "+std::string(u->ident));
  91                                                                         }
  92                                                                 }
  93                                                         }
  94                                                         return false;
  95                                                 }
  96                                         }
  97                                 }
  98                                 section = strtok_r(NULL,":",&savept);
  99                         }
 100                 }
 101                 return false;
 102         }
 103
 104         virtual void OnClose()
 105         {
 106                 // tidy up after ourselves when the connection is done.
 107                 // We receive this event straight after a timeout, too.
 108                 //
 109                 //
 110                 // OK, now listen up. The weird looking check here is
 111                 // REQUIRED. Don't try and optimize it away.
 112                 //
 113                 // When a socket is closed, it is not immediately removed
 114                 // from the socket list, there can be a short delay
 115                 // before it is culled from the list. This means that
 116                 // without this check, there is a chance that a user
 117                 // may not exist when we come to ::Shrink them, which
 118                 // results in a segfault. The value of "u" may not
 119                 // always be NULL at this point, so, what we do is
 120                 // check against the fd_ref_table, to see if (1) the user
 121                 // exists, and (2) its the SAME user, on the same file
 122                 // descriptor that they were when the lookup began.
 123                 //
 124                 // Fixes issue reported by webs, 7 Jun 2006
 125                 if (u && (Instance->SE->GetRef(ufd) == u))
 126                 {
 127                         u->Shrink("ident_data");
 128                 }
 129         }
 130
 131         virtual void OnError(InspSocketError e)
 132         {
 133                 if (u && (Instance->SE->GetRef(ufd) == u))
 134                 {
 135                         u->Shrink("ident_data");
 136                 }
 137         }
 138
 139         virtual bool OnConnected()
 140         {
 141                 if (u && (Instance->SE->GetRef(ufd) == u))
 142                 {
 143                         uslen = sizeof(sock_us);
 144                         themlen = sizeof(sock_them);
 145                         if ((getsockname(this->u->GetFd(),(sockaddr*)&sock_us,&uslen) || getpeername(this->u->GetFd(), (sockaddr*)&sock_them, &themlen)))
 146                         {
 147                                 Instance->Log(DEBUG,"BUG: Ident: failed to get socket names");
 148                                 return false;
 149                         }
 150                         else
 151                         {
 152                                 // send the request in the following format: theirsocket,oursocket
 153 #ifdef IPV6
 154                                 snprintf(ident_request,127,"%d,%d\r\n",ntohs(sock_them.sin6_port),ntohs(sock_us.sin6_port));
 155 #else
 156                                 snprintf(ident_request,127,"%d,%d\r\n",ntohs(sock_them.sin_port),ntohs(sock_us.sin_port));
 157 #endif
 158                                 this->Write(ident_request);
 159                                 return true;
 160                         }
 161                 }
 162                 else
 163                 {
 164                         return true;
 165                 }
 166         }
 167 };
 168
 169 class ModuleIdent : public Module
 170 {
 171
 172         ConfigReader* Conf;
 173
 174         int IdentTimeout;
 175
 176  public:
 177         void ReadSettings()
 178         {
 179                 Conf = new ConfigReader(ServerInstance);
 180                 IdentTimeout = Conf->ReadInteger("ident","timeout",0,true);
 181                 if (!IdentTimeout)
 182                         IdentTimeout = 1;
 183                 DELETE(Conf);
 184         }
 185
 186         ModuleIdent(InspIRCd* Me)
 187                 : Module::Module(Me)
 188         {
 189
 190                 ReadSettings();
 191         }
 192
 193         void Implements(char* List)
 194         {
 195                 List[I_OnCleanup] = List[I_OnRehash] = List[I_OnUserRegister] = List[I_OnCheckReady] = List[I_OnUserDisconnect] = 1;
 196         }
 197
 198         virtual void OnRehash(userrec* user, const std::string &parameter)
 199         {
 200                 ReadSettings();
 201         }
 202
 203         virtual int OnUserRegister(userrec* user)
 204         {
 205                 /*
 206                  * when the new user connects, before they authenticate with USER/NICK/PASS, we do
 207                  * their ident lookup. We do this by instantiating an object of type RFC1413, which
 208                  * is derived from InspSocket, and inserting it into the socket engine using the
 209                  * Server::AddSocket() call.
 210                  */
 211                 user->WriteServ("NOTICE "+std::string(user->nick)+" :*** Looking up your ident...");
 212                 RFC1413* ident = new RFC1413(ServerInstance, user, IdentTimeout);
 213                 if ((ident->GetState() == I_CONNECTING) || (ident->GetState() == I_CONNECTED))
 214                 {
 215                         user->Extend("ident_data", (char*)ident);
 216                 }
 217                 else
 218                 {
 219                         char newident[MAXBUF];
 220                         user->WriteServ("NOTICE "+std::string(user->nick)+" :*** Could not find your ident, using ~"+std::string(user->ident)+" instead.");
 221                         strcpy(newident,"~");
 222                         strlcat(newident,user->ident,IDENTMAX);
 223                         strlcpy(user->ident,newident,IDENTMAX);
 224                         delete ident;
 225                 }
 226                 return 0;
 227         }
 228
 229         virtual bool OnCheckReady(userrec* user)
 230         {
 231                 /*
 232                  * The socket engine will clean up their ident request for us when it completes,
 233                  * either due to timeout or due to closing, so, we just hold them until they dont
 234                  * have an ident field any more.
 235                  */
 236                 RFC1413* ident;
 237                 return (!user->GetExt("ident_data", ident));
 238         }
 239
 240         virtual void OnCleanup(int target_type, void* item)
 241         {
 242                 if (target_type == TYPE_USER)
 243                 {
 244                         userrec* user = (userrec*)item;
 245                         RFC1413* ident;
 246                         if (user->GetExt("ident_data", ident))
 247                         {
 248                                 // FIX: If the user record is deleted, the socket wont be removed
 249                                 // immediately so there is chance of the socket trying to write to
 250                                 // a user which has now vanished! To prevent this, set ident::u
 251                                 // to NULL and check it so that we dont write users who have gone away.
 252                                 ident->u = NULL;
 253                                 ServerInstance->SE->DelFd(ident);
 254                                 delete ident;
 255                         }
 256                 }
 257         }
 258
 259         virtual void OnUserDisconnect(userrec* user)
 260         {
 261                 /*
 262                  * when the user quits tidy up any ident lookup they have pending to keep things tidy.
 263                  * When we call RemoveSocket, the abstractions tied into the system evnetually work their
 264                  * way to RFC1459::OnClose(), which shrinks off the ident_data for us, so we dont need
 265                  * to do it here. If we don't tidy this up, there may still be lingering idents for users
 266                  * who have quit, as class RFC1459 is only loosely bound to userrec* via a pair of pointers
 267                  * and this would leave at least one of the invalid ;)
 268                  */
 269                 RFC1413* ident;
 270                 if (user->GetExt("ident_data", ident))
 271                 {
 272                         ident->u = NULL;
 273                         ServerInstance->SE->DelFd(ident);
 274                         delete ident;
 275                 }
 276         }
 277
 278         virtual ~ModuleIdent()
 279         {
 280         }
 281
 282         virtual Version GetVersion()
 283         {
 284                 return Version(1,1,0,0,VF_VENDOR,API_VERSION);
 285         }
 286
 287 };
 288
 289 class ModuleIdentFactory : public ModuleFactory
 290 {
 291  public:
 292         ModuleIdentFactory()
 293         {
 294         }
 295
 296         ~ModuleIdentFactory()
 297         {
 298         }
 299
 300         virtual Module * CreateModule(InspIRCd* Me)
 301         {
 302                 return new ModuleIdent(Me);
 303         }
 304
 305 };
 306
 307
 308 extern "C" void * init_module( void )
 309 {
 310         return new ModuleIdentFactory;
 311 }
 312