1 /* +------------------------------------+
2 * | Inspire Internet Relay Chat Daemon |
3 * +------------------------------------+
5 * InspIRCd: (C) 2002-2010 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 LocalUser *user; /* User we are attached to */
78 bool done; /* True if lookup is finished */
79 std::string result; /* Holds the ident string if done */
83 IdentRequestSocket(LocalUser* u) : user(u), result(u->ident)
85 age = ServerInstance->Time();
87 SetFd(socket(user->server_sa.sa.sa_family, SOCK_STREAM, 0));
90 throw ModuleException("Could not create socket");
94 irc::sockets::sockaddrs bindaddr;
95 irc::sockets::sockaddrs connaddr;
97 memcpy(&bindaddr, &user->server_sa, sizeof(bindaddr));
98 memcpy(&connaddr, &user->client_sa, sizeof(connaddr));
100 if (connaddr.sa.sa_family == AF_INET6)
102 bindaddr.in6.sin6_port = 0;
103 connaddr.in6.sin6_port = htons(113);
107 bindaddr.in4.sin_port = 0;
108 connaddr.in4.sin_port = htons(113);
111 /* Attempt to bind (ident requests must come from the ip the query is referring to */
112 if (ServerInstance->SE->Bind(GetFd(), bindaddr) < 0)
115 throw ModuleException("failed to bind()");
118 ServerInstance->SE->NonBlocking(GetFd());
120 /* Attempt connection (nonblocking) */
121 if (ServerInstance->SE->Connect(this, &connaddr.sa, connaddr.sa_size()) == -1 && errno != EINPROGRESS)
124 throw ModuleException("connect() failed");
127 /* Add fd to socket engine */
128 if (!ServerInstance->SE->AddFd(this, FD_WANT_NO_READ | FD_WANT_POLL_WRITE))
131 throw ModuleException("out of fds");
135 virtual void OnConnected()
137 ServerInstance->Logs->Log("m_ident",DEBUG,"OnConnected()");
138 ServerInstance->SE->ChangeEventMask(this, FD_WANT_POLL_READ | FD_WANT_NO_WRITE);
142 /* Build request in the form 'localport,remoteport\r\n' */
144 if (user->client_sa.sa.sa_family == AF_INET6)
145 req_size = snprintf(req, sizeof(req), "%d,%d\r\n",
146 ntohs(user->client_sa.in6.sin6_port), ntohs(user->server_sa.in6.sin6_port));
148 req_size = snprintf(req, sizeof(req), "%d,%d\r\n",
149 ntohs(user->client_sa.in4.sin_port), ntohs(user->server_sa.in4.sin_port));
151 /* Send failed if we didnt write the whole ident request --
152 * might as well give up if this happens!
154 if (ServerInstance->SE->Send(this, req, req_size, 0) < req_size)
158 virtual void HandleEvent(EventType et, int errornum = 0)
163 /* fd readable event, received ident response */
167 /* fd writeable event, successfully connected! */
171 /* fd error event, ohshi- */
172 ServerInstance->Logs->Log("m_ident",DEBUG,"EVENT_ERROR");
173 /* We *must* Close() here immediately or we get a
174 * huge storm of EVENT_ERROR events!
184 /* Remove ident socket from engine, and close it, but dont detatch it
185 * from its parent user class, or attempt to delete its memory.
189 ServerInstance->Logs->Log("m_ident",DEBUG,"Close ident socket %d", GetFd());
190 ServerInstance->SE->DelFd(this);
191 ServerInstance->SE->Close(GetFd());
192 ServerInstance->SE->Shutdown(GetFd(), SHUT_WR);
202 /* Note: if the lookup succeeded, will contain 'ident', otherwise
203 * will contain '~ident'. Use *GetResult() to determine lookup success.
205 const char* GetResult()
207 return result.c_str();
212 /* We don't really need to buffer for incomplete replies here, since IDENT replies are
213 * extremely short - there is *no* sane reason it'd be in more than one packet
216 int recvresult = ServerInstance->SE->Recv(this, ibuf, MAXBUF-1, 0);
218 /* Cant possibly be a valid response shorter than 3 chars,
219 * because the shortest possible response would look like: '1,1'
228 ServerInstance->Logs->Log("m_ident",DEBUG,"ReadResponse()");
230 irc::sepstream sep(ibuf, ':');
232 for (int i = 0; sep.GetToken(token); i++)
234 /* We only really care about the 4th portion */
240 /* Truncate the ident at any characters we don't like, skip leading spaces */
242 for (const char *j = token.c_str(); *j && (k < ServerInstance->Config->Limits.IdentMax + 1); j++)
247 /* Rules taken from InspIRCd::IsIdent */
248 if (((*j >= 'A') && (*j <= '}')) || ((*j >= '0') && (*j <= '9')) || (*j == '-') || (*j == '.'))
257 /* Re-check with IsIdent, in case that changes and this doesn't (paranoia!) */
258 if (!ident.empty() && ServerInstance->IsIdent(ident.c_str()))
266 /* Close (but dont delete from memory) our socket
275 class ModuleIdent : public Module
278 SimpleExtItem<IdentRequestSocket> ext;
280 ModuleIdent() : ext("ident_socket", this)
283 Implementation eventlist[] = { I_OnRehash, I_OnUserRegister, I_OnCheckReady, I_OnUserDisconnect };
284 ServerInstance->Modules->Attach(eventlist, this, 4);
291 virtual Version GetVersion()
293 return Version("Provides support for RFC1413 ident lookups", VF_VENDOR);
296 virtual void OnRehash(User *user)
300 RequestTimeout = Conf.ReadInteger("ident", "timeout", 0, true);
305 virtual ModResult OnUserRegister(LocalUser *user)
307 ConfigTag* tag = user->MyClass->config;
308 if (!tag->getBool("useident", true))
309 return MOD_RES_PASSTHRU;
311 /* User::ident is currently the username field from USER; with m_ident loaded, that
312 * should be preceded by a ~. The field is actually IdentMax+2 characters wide. */
313 if (user->ident.length() > ServerInstance->Config->Limits.IdentMax + 1)
314 user->ident.assign(user->ident, 0, ServerInstance->Config->Limits.IdentMax);
315 user->ident.insert(0, "~");
317 user->WriteServ("NOTICE Auth :*** Looking up your ident...");
321 IdentRequestSocket *isock = new IdentRequestSocket(IS_LOCAL(user));
322 ext.set(user, isock);
324 catch (ModuleException &e)
326 ServerInstance->Logs->Log("m_ident",DEBUG,"Ident exception: %s", e.GetReason());
329 return MOD_RES_PASSTHRU;
332 /* This triggers pretty regularly, we can use it in preference to
333 * creating a Timer object and especially better than creating a
334 * Timer per ident lookup!
336 virtual ModResult OnCheckReady(LocalUser *user)
338 /* Does user have an ident socket attached at all? */
339 IdentRequestSocket *isock = ext.get(user);
342 ServerInstance->Logs->Log("m_ident",DEBUG, "No ident socket :(");
343 return MOD_RES_PASSTHRU;
346 ServerInstance->Logs->Log("m_ident",DEBUG, "Has ident_socket");
348 time_t compare = isock->age;
349 compare += RequestTimeout;
351 /* Check for timeout of the socket */
352 if (ServerInstance->Time() >= compare)
355 user->WriteServ("NOTICE Auth :*** Ident request timed out.");
356 ServerInstance->Logs->Log("m_ident",DEBUG, "Timeout");
357 /* The user isnt actually disconnecting,
358 * we call this to clean up the user
360 OnUserDisconnect(user);
361 return MOD_RES_PASSTHRU;
364 /* Got a result yet? */
365 if (!isock->HasResult())
367 ServerInstance->Logs->Log("m_ident",DEBUG, "No result yet");
371 ServerInstance->Logs->Log("m_ident",DEBUG, "Yay, result!");
373 /* wooo, got a result (it will be good, or bad) */
374 if (*(isock->GetResult()) != '~')
375 user->WriteServ("NOTICE Auth :*** Found your ident, '%s'", isock->GetResult());
377 user->WriteServ("NOTICE Auth :*** Could not find your ident, using %s instead.", isock->GetResult());
379 /* Copy the ident string to the user */
380 user->ChangeIdent(isock->GetResult());
382 /* The user isnt actually disconnecting, we call this to clean up the user */
383 OnUserDisconnect(user);
384 return MOD_RES_PASSTHRU;
387 virtual void OnCleanup(int target_type, void *item)
389 /* Module unloading, tidy up users */
390 if (target_type == TYPE_USER)
391 OnUserDisconnect((LocalUser*)item);
394 virtual void OnUserDisconnect(LocalUser *user)
396 /* User disconnect (generic socket detatch event) */
397 IdentRequestSocket *isock = ext.get(user);
406 MODULE_INIT(ModuleIdent)