2 * InspIRCd -- Internet Relay Chat Daemon
4 * Copyright (C) 2009-2010 Daniel De Graaf <danieldg@inspircd.org>
5 * Copyright (C) 2007, 2009 John Brooks <john.brooks@dereferenced.net>
6 * Copyright (C) 2006-2008 Robin Burchell <robin+git@viroteck.net>
7 * Copyright (C) 2005-2008 Craig Edwards <craigedwards@brainbox.cc>
8 * Copyright (C) 2008 Thomas Stagner <aquanight@inspircd.org>
9 * Copyright (C) 2007 Dennis Friis <peavey@inspircd.org>
11 * This file is part of InspIRCd. InspIRCd is free software: you can
12 * redistribute it and/or modify it under the terms of the GNU General Public
13 * License as published by the Free Software Foundation, version 2.
15 * This program is distributed in the hope that it will be useful, but WITHOUT
16 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
17 * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
20 * You should have received a copy of the GNU General Public License
21 * along with this program. If not, see <http://www.gnu.org/licenses/>.
27 /* $ModDesc: Provides support for RFC1413 ident lookups */
29 /* --------------------------------------------------------------
30 * Note that this is the third incarnation of m_ident. The first
31 * two attempts were pretty crashy, mainly due to the fact we tried
32 * to use InspSocket/BufferedSocket to make them work. This class
33 * is ok for more heavyweight tasks, it does a lot of things behind
34 * the scenes that are not good for ident sockets and it has a huge
37 * To fix all the issues that we had in the old ident modules (many
38 * nasty race conditions that would cause segfaults etc) we have
39 * rewritten this module to use a simplified socket object based
40 * directly off EventHandler. As EventHandler only has low level
41 * readability, writeability and error events tied directly to the
42 * socket engine, this makes our lives easier as nothing happens to
43 * our ident lookup class that is outside of this module, or out-
44 * side of the control of the class. There are no timers, internal
45 * events, or such, which will cause the socket to be deleted,
46 * queued for deletion, etc. In fact, theres not even any queueing!
48 * Using this framework we have a much more stable module.
50 * A few things to note:
52 * O The only place that may *delete* an active or inactive
53 * ident socket is OnUserDisconnect in the module class.
54 * Because this is out of scope of the socket class there is
55 * no possibility that the socket may ever try to delete
58 * O Closure of the ident socket with the Close() method will
59 * not cause removal of the socket from memory or detatchment
60 * from its 'parent' User class. It will only flag it as an
61 * inactive socket in the socket engine.
63 * O Timeouts are handled in OnCheckReaady at the same time as
64 * checking if the ident socket has a result. This is done
65 * by checking if the age the of the class (its instantiation
66 * time) plus the timeout value is greater than the current time.
68 * O The ident socket is able to but should not modify its
69 * 'parent' user directly. Instead the ident socket class sets
70 * a completion flag and during the next call to OnCheckReady,
71 * the completion flag will be checked and any result copied to
72 * that user's class. This again ensures a single point of socket
73 * deletion for safer, neater code.
75 * O The code in the constructor of the ident socket is taken from
76 * BufferedSocket but majorly thinned down. It works for both
79 * O In the event that the ident socket throws a ModuleException,
80 * nothing is done. This is counted as total and complete
81 * failure to create a connection.
82 * --------------------------------------------------------------
85 class IdentRequestSocket : public EventHandler
88 LocalUser *user; /* User we are attached to */
89 std::string result; /* Holds the ident string if done */
91 bool done; /* True if lookup is finished */
93 IdentRequestSocket(LocalUser* u) : user(u)
95 age = ServerInstance->Time();
97 SetFd(socket(user->server_sa.sa.sa_family, SOCK_STREAM, 0));
100 throw ModuleException("Could not create socket");
104 irc::sockets::sockaddrs bindaddr;
105 irc::sockets::sockaddrs connaddr;
107 memcpy(&bindaddr, &user->server_sa, sizeof(bindaddr));
108 memcpy(&connaddr, &user->client_sa, sizeof(connaddr));
110 if (connaddr.sa.sa_family == AF_INET6)
112 bindaddr.in6.sin6_port = 0;
113 connaddr.in6.sin6_port = htons(113);
117 bindaddr.in4.sin_port = 0;
118 connaddr.in4.sin_port = htons(113);
121 /* Attempt to bind (ident requests must come from the ip the query is referring to */
122 if (ServerInstance->SE->Bind(GetFd(), bindaddr) < 0)
125 throw ModuleException("failed to bind()");
128 ServerInstance->SE->NonBlocking(GetFd());
130 /* Attempt connection (nonblocking) */
131 if (ServerInstance->SE->Connect(this, &connaddr.sa, connaddr.sa_size()) == -1 && errno != EINPROGRESS)
134 throw ModuleException("connect() failed");
137 /* Add fd to socket engine */
138 if (!ServerInstance->SE->AddFd(this, FD_WANT_NO_READ | FD_WANT_POLL_WRITE))
141 throw ModuleException("out of fds");
147 ServerInstance->Logs->Log("m_ident", LOG_DEBUG, "OnConnected()");
148 ServerInstance->SE->ChangeEventMask(this, FD_WANT_POLL_READ | FD_WANT_NO_WRITE);
152 /* Build request in the form 'localport,remoteport\r\n' */
154 if (user->client_sa.sa.sa_family == AF_INET6)
155 req_size = snprintf(req, sizeof(req), "%d,%d\r\n",
156 ntohs(user->client_sa.in6.sin6_port), ntohs(user->server_sa.in6.sin6_port));
158 req_size = snprintf(req, sizeof(req), "%d,%d\r\n",
159 ntohs(user->client_sa.in4.sin_port), ntohs(user->server_sa.in4.sin_port));
161 /* Send failed if we didnt write the whole ident request --
162 * might as well give up if this happens!
164 if (ServerInstance->SE->Send(this, req, req_size, 0) < req_size)
168 void HandleEvent(EventType et, int errornum = 0)
173 /* fd readable event, received ident response */
177 /* fd writeable event, successfully connected! */
181 /* fd error event, ohshi- */
182 ServerInstance->Logs->Log("m_ident", LOG_DEBUG, "EVENT_ERROR");
183 /* We *must* Close() here immediately or we get a
184 * huge storm of EVENT_ERROR events!
194 /* Remove ident socket from engine, and close it, but dont detatch it
195 * from its parent user class, or attempt to delete its memory.
199 ServerInstance->Logs->Log("m_ident", LOG_DEBUG, "Close ident socket %d", GetFd());
200 ServerInstance->SE->DelFd(this);
201 ServerInstance->SE->Close(GetFd());
213 /* We don't really need to buffer for incomplete replies here, since IDENT replies are
214 * extremely short - there is *no* sane reason it'd be in more than one packet
217 int recvresult = ServerInstance->SE->Recv(this, ibuf, MAXBUF-1, 0);
219 /* Close (but don't delete from memory) our socket
220 * and flag as done since the ident lookup has finished
225 /* Cant possibly be a valid response shorter than 3 chars,
226 * because the shortest possible response would look like: '1,1'
231 ServerInstance->Logs->Log("m_ident", LOG_DEBUG, "ReadResponse()");
233 /* Truncate at the first null character, but first make sure
234 * there is at least one null char (at the end of the buffer).
236 ibuf[recvresult] = '\0';
237 std::string buf(ibuf);
239 /* <2 colons: invalid
240 * 2 colons: reply is an error
241 * >3 colons: there is a colon in the ident
243 if (std::count(buf.begin(), buf.end(), ':') != 3)
246 std::string::size_type lastcolon = buf.rfind(':');
248 /* Truncate the ident at any characters we don't like, skip leading spaces */
249 for (std::string::const_iterator i = buf.begin()+lastcolon+1; i != buf.end(); ++i)
251 if (result.size() == ServerInstance->Config->Limits.IdentMax)
252 /* Ident is getting too long */
258 /* Add the next char to the result and see if it's still a valid ident,
259 * according to IsIdent(). If it isn't, then erase what we just added and
263 if (!ServerInstance->IsIdent(result.c_str()))
265 result.erase(result.end()-1);
272 class ModuleIdent : public Module
275 SimpleExtItem<IdentRequestSocket> ext;
277 ModuleIdent() : ext("ident_socket", this)
281 void init() CXX11_OVERRIDE
283 ServerInstance->Modules->AddService(ext);
285 Implementation eventlist[] = {
286 I_OnRehash, I_OnUserInit, I_OnCheckReady,
287 I_OnUserDisconnect, I_OnSetConnectClass
289 ServerInstance->Modules->Attach(eventlist, this, sizeof(eventlist)/sizeof(Implementation));
292 Version GetVersion() CXX11_OVERRIDE
294 return Version("Provides support for RFC1413 ident lookups", VF_VENDOR);
297 void OnRehash(User *user) CXX11_OVERRIDE
299 RequestTimeout = ServerInstance->Config->ConfValue("ident")->getInt("timeout", 5);
304 void OnUserInit(LocalUser *user) CXX11_OVERRIDE
306 ConfigTag* tag = user->MyClass->config;
307 if (!tag->getBool("useident", true))
310 user->WriteNotice("*** Looking up your ident...");
314 IdentRequestSocket *isock = new IdentRequestSocket(IS_LOCAL(user));
315 ext.set(user, isock);
317 catch (ModuleException &e)
319 ServerInstance->Logs->Log("m_ident", LOG_DEBUG, "Ident exception: %s", e.GetReason());
323 /* This triggers pretty regularly, we can use it in preference to
324 * creating a Timer object and especially better than creating a
325 * Timer per ident lookup!
327 ModResult OnCheckReady(LocalUser *user) CXX11_OVERRIDE
329 /* Does user have an ident socket attached at all? */
330 IdentRequestSocket *isock = ext.get(user);
333 ServerInstance->Logs->Log("m_ident", LOG_DEBUG, "No ident socket :(");
334 return MOD_RES_PASSTHRU;
337 ServerInstance->Logs->Log("m_ident", LOG_DEBUG, "Has ident_socket");
339 time_t compare = isock->age;
340 compare += RequestTimeout;
342 /* Check for timeout of the socket */
343 if (ServerInstance->Time() >= compare)
346 user->WriteNotice("*** Ident request timed out.");
347 ServerInstance->Logs->Log("m_ident", LOG_DEBUG, "Timeout");
349 else if (!isock->HasResult())
351 // time still good, no result yet... hold the registration
352 ServerInstance->Logs->Log("m_ident", LOG_DEBUG, "No result yet");
356 ServerInstance->Logs->Log("m_ident", LOG_DEBUG, "Yay, result!");
358 /* wooo, got a result (it will be good, or bad) */
359 if (isock->result.empty())
361 user->ident.insert(0, 1, '~');
362 user->WriteNotice("*** Could not find your ident, using " + user->ident + " instead.");
366 user->ident = isock->result;
367 user->WriteNotice("*** Found your ident, '" + user->ident + "'");
370 user->InvalidateCache();
373 return MOD_RES_PASSTHRU;
376 ModResult OnSetConnectClass(LocalUser* user, ConnectClass* myclass) CXX11_OVERRIDE
378 if (myclass->config->getBool("requireident") && user->ident[0] == '~')
380 return MOD_RES_PASSTHRU;
383 void OnCleanup(int target_type, void *item) CXX11_OVERRIDE
385 /* Module unloading, tidy up users */
386 if (target_type == TYPE_USER)
388 LocalUser* user = IS_LOCAL((User*) item);
390 OnUserDisconnect(user);
394 void OnUserDisconnect(LocalUser *user) CXX11_OVERRIDE
396 /* User disconnect (generic socket detatch event) */
397 IdentRequestSocket *isock = ext.get(user);
406 MODULE_INIT(ModuleIdent)