1 /* +------------------------------------+
2 * | Inspire Internet Relay Chat Daemon |
3 * +------------------------------------+
5 * InspIRCd: (C) 2002-2009 InspIRCd Development Team
6 * See: http://wiki.inspircd.org/Credits
8 * This program is free but copyrighted software; see
9 * the file COPYING for details.
11 * ---------------------------------------------------
16 /* $ModDesc: Provides support for RFC1413 ident lookups */
18 /* --------------------------------------------------------------
19 * Note that this is the third incarnation of m_ident. The first
20 * two attempts were pretty crashy, mainly due to the fact we tried
21 * to use InspSocket/BufferedSocket to make them work. This class
22 * is ok for more heavyweight tasks, it does a lot of things behind
23 * the scenes that are not good for ident sockets and it has a huge
26 * To fix all the issues that we had in the old ident modules (many
27 * nasty race conditions that would cause segfaults etc) we have
28 * rewritten this module to use a simplified socket object based
29 * directly off EventHandler. As EventHandler only has low level
30 * readability, writeability and error events tied directly to the
31 * socket engine, this makes our lives easier as nothing happens to
32 * our ident lookup class that is outside of this module, or out-
33 * side of the control of the class. There are no timers, internal
34 * events, or such, which will cause the socket to be deleted,
35 * queued for deletion, etc. In fact, theres not even any queueing!
37 * Using this framework we have a much more stable module.
39 * A few things to note:
41 * O The only place that may *delete* an active or inactive
42 * ident socket is OnUserDisconnect in the module class.
43 * Because this is out of scope of the socket class there is
44 * no possibility that the socket may ever try to delete
47 * O Closure of the ident socket with the Close() method will
48 * not cause removal of the socket from memory or detatchment
49 * from its 'parent' User class. It will only flag it as an
50 * inactive socket in the socket engine.
52 * O Timeouts are handled in OnCheckReaady at the same time as
53 * checking if the ident socket has a result. This is done
54 * by checking if the age the of the class (its instantiation
55 * time) plus the timeout value is greater than the current time.
57 * O The ident socket is able to but should not modify its
58 * 'parent' user directly. Instead the ident socket class sets
59 * a completion flag and during the next call to OnCheckReady,
60 * the completion flag will be checked and any result copied to
61 * that user's class. This again ensures a single point of socket
62 * deletion for safer, neater code.
64 * O The code in the constructor of the ident socket is taken from
65 * BufferedSocket but majorly thinned down. It works for both
68 * O In the event that the ident socket throws a ModuleException,
69 * nothing is done. This is counted as total and complete
70 * failure to create a connection.
71 * --------------------------------------------------------------
74 class IdentRequestSocket : public EventHandler
77 User *user; /* User we are attached to */
78 InspIRCd* ServerInstance; /* Server instance */
79 bool done; /* True if lookup is finished */
80 std::string result; /* Holds the ident string if done */
84 IdentRequestSocket(InspIRCd *Server, User* u) : user(u), ServerInstance(Server), result(u->ident)
86 age = ServerInstance->Time();
89 SetFd(socket(user->server_sa.sa.sa_family, SOCK_STREAM, 0));
92 throw ModuleException("Could not create socket");
96 irc::sockets::sockaddrs bindaddr;
97 irc::sockets::sockaddrs connaddr;
99 memcpy(&bindaddr, &user->server_sa, sizeof(bindaddr));
100 memcpy(&connaddr, &user->client_sa, sizeof(connaddr));
102 if (connaddr.sa.sa_family == AF_INET6)
104 bindaddr.in6.sin6_port = 0;
105 connaddr.in6.sin6_port = htons(113);
109 bindaddr.in4.sin_port = 0;
110 connaddr.in4.sin_port = htons(113);
113 /* Attempt to bind (ident requests must come from the ip the query is referring to */
114 if (ServerInstance->SE->Bind(GetFd(), &bindaddr.sa, size) < 0)
117 throw ModuleException("failed to bind()");
120 ServerInstance->SE->NonBlocking(GetFd());
122 /* Attempt connection (nonblocking) */
123 if (ServerInstance->SE->Connect(this, &connaddr.sa, size) == -1 && errno != EINPROGRESS)
126 throw ModuleException("connect() failed");
129 /* Add fd to socket engine */
130 if (!ServerInstance->SE->AddFd(this))
133 throw ModuleException("out of fds");
136 /* Important: We set WantWrite immediately after connect()
137 * because a successful connection will trigger a writability event
139 ServerInstance->SE->WantWrite(this);
142 virtual void OnConnected()
144 ServerInstance->Logs->Log("m_ident",DEBUG,"OnConnected()");
148 /* Build request in the form 'localport,remoteport\r\n' */
150 if (user->client_sa.sa.sa_family == AF_INET6)
151 req_size = snprintf(req, sizeof(req), "%d,%d\r\n",
152 ntohs(user->client_sa.in6.sin6_port), ntohs(user->server_sa.in6.sin6_port));
154 req_size = snprintf(req, sizeof(req), "%d,%d\r\n",
155 ntohs(user->client_sa.in4.sin_port), ntohs(user->server_sa.in4.sin_port));
157 /* Send failed if we didnt write the whole ident request --
158 * might as well give up if this happens!
160 if (ServerInstance->SE->Send(this, req, req_size, 0) < req_size)
164 virtual void HandleEvent(EventType et, int errornum = 0)
169 /* fd readable event, received ident response */
173 /* fd writeable event, successfully connected! */
177 /* fd error event, ohshi- */
178 ServerInstance->Logs->Log("m_ident",DEBUG,"EVENT_ERROR");
179 /* We *must* Close() here immediately or we get a
180 * huge storm of EVENT_ERROR events!
190 /* Remove ident socket from engine, and close it, but dont detatch it
191 * from its parent user class, or attempt to delete its memory.
195 ServerInstance->Logs->Log("m_ident",DEBUG,"Close ident socket %d", GetFd());
196 ServerInstance->SE->DelFd(this);
197 ServerInstance->SE->Close(GetFd());
198 ServerInstance->SE->Shutdown(GetFd(), SHUT_WR);
208 /* Note: if the lookup succeeded, will contain 'ident', otherwise
209 * will contain '~ident'. Use *GetResult() to determine lookup success.
211 const char* GetResult()
213 return result.c_str();
218 /* We don't really need to buffer for incomplete replies here, since IDENT replies are
219 * extremely short - there is *no* sane reason it'd be in more than one packet
222 int recvresult = ServerInstance->SE->Recv(this, ibuf, MAXBUF-1, 0);
224 /* Cant possibly be a valid response shorter than 3 chars,
225 * because the shortest possible response would look like: '1,1'
234 ServerInstance->Logs->Log("m_ident",DEBUG,"ReadResponse()");
236 irc::sepstream sep(ibuf, ':');
238 for (int i = 0; sep.GetToken(token); i++)
240 /* We only really care about the 4th portion */
246 /* Truncate the ident at any characters we don't like, skip leading spaces */
248 for (const char *j = token.c_str(); *j && (k < ServerInstance->Config->Limits.IdentMax + 1); j++)
253 /* Rules taken from InspIRCd::IsIdent */
254 if (((*j >= 'A') && (*j <= '}')) || ((*j >= '0') && (*j <= '9')) || (*j == '-') || (*j == '.'))
263 /* Re-check with IsIdent, in case that changes and this doesn't (paranoia!) */
264 if (!ident.empty() && ServerInstance->IsIdent(ident.c_str()))
272 /* Close (but dont delete from memory) our socket
281 class ModuleIdent : public Module
285 SimpleExtItem<IdentRequestSocket> ext;
287 ModuleIdent(InspIRCd *Me) : Module(Me), ext("ident_socket", this)
289 Conf = new ConfigReader(ServerInstance);
291 Implementation eventlist[] = { I_OnRehash, I_OnUserRegister, I_OnCheckReady, I_OnCleanup, I_OnUserDisconnect };
292 ServerInstance->Modules->Attach(eventlist, this, 5);
300 virtual Version GetVersion()
302 return Version("$Id$", VF_VENDOR, API_VERSION);
305 virtual void OnRehash(User *user)
308 Conf = new ConfigReader(ServerInstance);
310 RequestTimeout = Conf->ReadInteger("ident", "timeout", 0, true);
315 virtual ModResult OnUserRegister(User *user)
317 for (int j = 0; j < Conf->Enumerate("connect"); j++)
319 std::string hostn = Conf->ReadValue("connect","allow",j);
320 /* XXX: Fixme: does not respect port, limit, etc */
321 if ((InspIRCd::MatchCIDR(user->GetIPString(),hostn, ascii_case_insensitive_map)) || (InspIRCd::Match(user->host,hostn, ascii_case_insensitive_map)))
323 bool useident = Conf->ReadFlag("connect", "useident", "yes", j);
326 return MOD_RES_PASSTHRU;
330 /* User::ident is currently the username field from USER; with m_ident loaded, that
331 * should be preceded by a ~. The field is actually IdentMax+2 characters wide. */
332 if (user->ident.length() > ServerInstance->Config->Limits.IdentMax + 1)
333 user->ident.assign(user->ident, 0, ServerInstance->Config->Limits.IdentMax);
334 user->ident.insert(0, "~");
336 user->WriteServ("NOTICE Auth :*** Looking up your ident...");
340 IdentRequestSocket *isock = new IdentRequestSocket(ServerInstance, user);
341 ext.set(user, isock);
343 catch (ModuleException &e)
345 ServerInstance->Logs->Log("m_ident",DEBUG,"Ident exception: %s", e.GetReason());
348 return MOD_RES_PASSTHRU;
351 /* This triggers pretty regularly, we can use it in preference to
352 * creating a Timer object and especially better than creating a
353 * Timer per ident lookup!
355 virtual ModResult OnCheckReady(User *user)
357 /* Does user have an ident socket attached at all? */
358 IdentRequestSocket *isock = ext.get(user);
361 ServerInstance->Logs->Log("m_ident",DEBUG, "No ident socket :(");
362 return MOD_RES_PASSTHRU;
365 ServerInstance->Logs->Log("m_ident",DEBUG, "Has ident_socket");
367 time_t compare = isock->age;
368 compare += RequestTimeout;
370 /* Check for timeout of the socket */
371 if (ServerInstance->Time() >= compare)
374 user->WriteServ("NOTICE Auth :*** Ident request timed out.");
375 ServerInstance->Logs->Log("m_ident",DEBUG, "Timeout");
376 /* The user isnt actually disconnecting,
377 * we call this to clean up the user
379 OnUserDisconnect(user);
380 return MOD_RES_PASSTHRU;
383 /* Got a result yet? */
384 if (!isock->HasResult())
386 ServerInstance->Logs->Log("m_ident",DEBUG, "No result yet");
390 ServerInstance->Logs->Log("m_ident",DEBUG, "Yay, result!");
392 /* wooo, got a result (it will be good, or bad) */
393 if (*(isock->GetResult()) != '~')
394 user->WriteServ("NOTICE Auth :*** Found your ident, '%s'", isock->GetResult());
396 user->WriteServ("NOTICE Auth :*** Could not find your ident, using %s instead.", isock->GetResult());
398 /* Copy the ident string to the user */
399 user->ChangeIdent(isock->GetResult());
401 /* The user isnt actually disconnecting, we call this to clean up the user */
402 OnUserDisconnect(user);
403 return MOD_RES_PASSTHRU;
406 virtual void OnCleanup(int target_type, void *item)
408 /* Module unloading, tidy up users */
409 if (target_type == TYPE_USER)
410 OnUserDisconnect((User*)item);
413 virtual void OnUserDisconnect(User *user)
415 /* User disconnect (generic socket detatch event) */
416 IdentRequestSocket *isock = ext.get(user);
425 MODULE_INIT(ModuleIdent)