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 "inspircd.h"
  15
  16 /* $ModDesc: Provides support for RFC 1413 ident lookups */
  17
  18 // Version 1.5.0.0 - Updated to use InspSocket, faster and neater.
  19
  20 /** Handles RFC1413 ident connections to users
  21  */
  22 class RFC1413 : public InspSocket
  23 {
  24  protected:
  25         socklen_t uslen;         // length of our port number
  26         socklen_t themlen;       // length of their port number
  27         char ident_request[128]; // buffer used to make up the request string
  28  public:
  29
  30         userrec* u;              // user record that the lookup is associated with
  31         int ufd;
  32
  33         RFC1413(InspIRCd* SI, userrec* user, int maxtime, const std::string &bindto) : InspSocket(SI, user->GetIPString(), 113, false, maxtime, bindto), u(user)
  34         {
  35                 ufd = user->GetFd();
  36         }
  37
  38         virtual void OnTimeout()
  39         {
  40                 // When we timeout, the connection failed within the allowed timeframe,
  41                 // so we just display a notice, and tidy off the ident_data.
  42                 if (u && (Instance->SE->GetRef(ufd) == u))
  43                 {
  44                         u->Shrink("ident_data");
  45                         Instance->next_call = Instance->Time();
  46                 }
  47         }
  48
  49         virtual bool OnDataReady()
  50         {
  51                 char* ibuf = this->Read();
  52                 if (ibuf)
  53                 {
  54                         char* savept;
  55                         char* section = strtok_r(ibuf,":",&savept);
  56                         while (section)
  57                         {
  58                                 if (strstr(section,"USERID"))
  59                                 {
  60                                         section = strtok_r(NULL,":",&savept);
  61                                         if (section)
  62                                         {
  63                                                 // ID type, usually UNIX or OTHER... we dont want it, so read the next token
  64                                                 section = strtok_r(NULL,":",&savept);
  65                                                 if (section)
  66                                                 {
  67                                                         while (*section == ' ') section++; // strip leading spaces
  68                                                         for (char* j = section; *j; j++)
  69                                                         if ((*j < 33) || (*j > 126))
  70                                                                 *j = '\0'; // truncate at invalid chars
  71                                                         if (*section)
  72                                                         {
  73                                                                 if (u && (Instance->SE->GetRef(ufd) == u))
  74                                                                 {
  75                                                                         if (this->Instance->IsIdent(section))
  76                                                                         {
  77                                                                                 u->Extend("IDENT", new std::string(std::string(section) + "," + std::string(u->ident)));
  78                                                                                 strlcpy(u->ident,section,IDENTMAX);
  79                                                                                 u->WriteServ("NOTICE "+std::string(u->nick)+" :*** Found your ident: "+std::string(u->ident));
  80                                                                         }
  81                                                                 }
  82                                                         }
  83                                                         return false;
  84                                                 }
  85                                         }
  86                                 }
  87                                 section = strtok_r(NULL,":",&savept);
  88                         }
  89                 }
  90                 return false;
  91         }
  92
  93         virtual void OnClose()
  94         {
  95                 // tidy up after ourselves when the connection is done.
  96                 // We receive this event straight after a timeout, too.
  97                 //
  98                 //
  99                 // OK, now listen up. The weird looking check here is
 100                 // REQUIRED. Don't try and optimize it away.
 101                 //
 102                 // When a socket is closed, it is not immediately removed
 103                 // from the socket list, there can be a short delay
 104                 // before it is culled from the list. This means that
 105                 // without this check, there is a chance that a user
 106                 // may not exist when we come to ::Shrink them, which
 107                 // results in a segfault. The value of "u" may not
 108                 // always be NULL at this point, so, what we do is
 109                 // check against the fd_ref_table, to see if (1) the user
 110                 // exists, and (2) its the SAME user, on the same file
 111                 // descriptor that they were when the lookup began.
 112                 //
 113                 // Fixes issue reported by webs, 7 Jun 2006
 114                 if (u && (Instance->SE->GetRef(ufd) == u))
 115                 {
 116                         Instance->next_call = Instance->Time();
 117                         u->Shrink("ident_data");
 118                 }
 119         }
 120
 121         virtual void OnError(InspSocketError e)
 122         {
 123                 if (u && (Instance->SE->GetRef(ufd) == u))
 124                 {
 125                         if (*u->ident == '~')
 126                                 u->WriteServ("NOTICE "+std::string(u->nick)+" :*** Could not find your ident, using "+std::string(u->ident)+" instead.");
 127
 128                         Instance->next_call = Instance->Time();
 129                         u->Shrink("ident_data");
 130                 }
 131         }
 132
 133         virtual bool OnConnected()
 134         {
 135                 if (u && (Instance->SE->GetRef(ufd) == u))
 136                 {
 137                         sockaddr* sock_us = new sockaddr[2];
 138                         sockaddr* sock_them = new sockaddr[2];
 139                         bool success = false;
 140                         uslen = sizeof(sockaddr_in);
 141                         themlen = sizeof(sockaddr_in);
 142 #ifdef IPV6
 143                         if (this->u->GetProtocolFamily() == AF_INET6)
 144                         {
 145                                 themlen = sizeof(sockaddr_in6);
 146                                 uslen = sizeof(sockaddr_in6);
 147                         }
 148 #endif
 149                         success = ((getsockname(this->u->GetFd(),sock_us,&uslen) || getpeername(this->u->GetFd(), sock_them, &themlen)));
 150                         if (success)
 151                         {
 152                                 delete[] sock_us;
 153                                 delete[] sock_them;
 154                                 return false;
 155                         }
 156                         else
 157                         {
 158                                 // send the request in the following format: theirsocket,oursocket
 159 #ifdef IPV6
 160                                 if (this->u->GetProtocolFamily() == AF_INET6)
 161                                         snprintf(ident_request,127,"%d,%d\r\n",ntohs(((sockaddr_in6*)sock_them)->sin6_port),ntohs(((sockaddr_in6*)sock_us)->sin6_port));
 162                                 else
 163 #endif
 164                                 snprintf(ident_request,127,"%d,%d\r\n",ntohs(((sockaddr_in*)sock_them)->sin_port),ntohs(((sockaddr_in*)sock_us)->sin_port));
 165                                 this->Write(ident_request);
 166                                 delete[] sock_us;
 167                                 delete[] sock_them;
 168                                 return true;
 169                         }
 170                 }
 171                 else
 172                 {
 173                         Instance->next_call = Instance->Time();
 174                         return true;
 175                 }
 176         }
 177 };
 178
 179 class ModuleIdent : public Module
 180 {
 181
 182         ConfigReader* Conf;
 183         int IdentTimeout;
 184         std::string PortBind;
 185
 186  public:
 187         void ReadSettings()
 188         {
 189                 Conf = new ConfigReader(ServerInstance);
 190                 IdentTimeout = Conf->ReadInteger("ident", "timeout", 0, true);
 191                 PortBind = Conf->ReadValue("ident", "bind", 0);
 192
 193                 if (!IdentTimeout)
 194                         IdentTimeout = 1;
 195
 196                 delete Conf;
 197         }
 198
 199         ModuleIdent(InspIRCd* Me)
 200                 : Module(Me)
 201         {
 202
 203                 ReadSettings();
 204         }
 205
 206         void Implements(char* List)
 207         {
 208                 List[I_OnCleanup] = List[I_OnRehash] = List[I_OnUserRegister] = List[I_OnCheckReady] = List[I_OnUserDisconnect] = 1;
 209         }
 210
 211         void OnSyncUserMetaData(userrec* user, Module* proto,void* opaque, const std::string &extname, bool displayable)
 212         {
 213                 if ((displayable) && (extname == "IDENT"))
 214                 {
 215                         std::string* ident;
 216                         if (GetExt("IDENT", ident))
 217                                 proto->ProtoSendMetaData(opaque, TYPE_USER, user, extname, *ident);
 218                 }
 219         }
 220
 221
 222         virtual void OnRehash(userrec* user, const std::string &parameter)
 223         {
 224                 ReadSettings();
 225         }
 226
 227         virtual int OnUserRegister(userrec* user)
 228         {
 229                 /*
 230                  * when the new user connects, before they authenticate with USER/NICK/PASS, we do
 231                  * their ident lookup. We do this by instantiating an object of type RFC1413, which
 232                  * is derived from InspSocket, and inserting it into the socket engine using the
 233                  * Server::AddSocket() call.
 234                  */
 235                 char newident[MAXBUF];
 236                 strcpy(newident,"~");
 237                 strlcat(newident,user->ident,IDENTMAX);
 238                 strlcpy(user->ident,newident,IDENTMAX);
 239
 240
 241                 user->WriteServ("NOTICE "+std::string(user->nick)+" :*** Looking up your ident...");
 242                 RFC1413* ident = new RFC1413(ServerInstance, user, IdentTimeout, PortBind);
 243                 if ((ident->GetState() == I_CONNECTING) || (ident->GetState() == I_CONNECTED))
 244                 {
 245                         user->Extend("ident_data", (char*)ident);
 246                 }
 247                 else
 248                 {
 249                         user->WriteServ("NOTICE "+std::string(user->nick)+" :*** Could not find your ident, using "+std::string(user->ident)+" instead.");
 250                         ServerInstance->next_call = ServerInstance->Time();
 251                 }
 252                 return 0;
 253         }
 254
 255         virtual bool OnCheckReady(userrec* user)
 256         {
 257                 /*
 258                  * The socket engine will clean up their ident request for us when it completes,
 259                  * either due to timeout or due to closing, so, we just hold them until they dont
 260                  * have an ident field any more.
 261                  */
 262                 RFC1413* ident;
 263                 return (!user->GetExt("ident_data", ident));
 264         }
 265
 266         virtual void OnCleanup(int target_type, void* item)
 267         {
 268                 if (target_type == TYPE_USER)
 269                 {
 270                         userrec* user = (userrec*)item;
 271                         RFC1413* ident;
 272                         std::string* identstr;
 273                         if (user->GetExt("ident_data", ident))
 274                         {
 275                                 // FIX: If the user record is deleted, the socket wont be removed
 276                                 // immediately so there is chance of the socket trying to write to
 277                                 // a user which has now vanished! To prevent this, set ident::u
 278                                 // to NULL and check it so that we dont write users who have gone away.
 279                                 ident->u = NULL;
 280                                 ServerInstance->SE->DelFd(ident);
 281                         }
 282                         if (user->GetExt("IDENT", identstr))
 283                         {
 284                                 delete identstr;
 285                                 user->Shrink("IDENT");
 286                         }
 287                 }
 288         }
 289
 290         virtual void OnUserDisconnect(userrec* user)
 291         {
 292                 /*
 293                  * when the user quits tidy up any ident lookup they have pending to keep things tidy.
 294                  * When we call RemoveSocket, the abstractions tied into the system evnetually work their
 295                  * way to RFC1459::OnClose(), which shrinks off the ident_data for us, so we dont need
 296                  * to do it here. If we don't tidy this up, there may still be lingering idents for users
 297                  * who have quit, as class RFC1459 is only loosely bound to userrec* via a pair of pointers
 298                  * and this would leave at least one of the invalid ;)
 299                  */
 300                 RFC1413* ident;
 301                 std::string* identstr;
 302                 if (user->GetExt("ident_data", ident))
 303                 {
 304                         ident->u = NULL;
 305                         ServerInstance->SE->DelFd(ident);
 306                 }
 307                 if (user->GetExt("IDENT", identstr))
 308                 {
 309                         delete identstr;
 310                         user->Shrink("IDENT");
 311                 }
 312         }
 313
 314         virtual ~ModuleIdent()
 315         {
 316                 ServerInstance->next_call = ServerInstance->Time();
 317         }
 318
 319         virtual Version GetVersion()
 320         {
 321                 return Version(1,1,0,0,VF_VENDOR,API_VERSION);
 322         }
 323
 324 };
 325
 326 MODULE_INIT(ModuleIdent)