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/>.
29 // Either the ident looup has not started yet or the user is registered.
32 // Ident lookups are not enabled and a user has been marked as being skipped.
35 // Ident looups are not enabled and a user has been an insecure ident prefix.
38 // An ident lookup was done and an ident was found.
41 // An ident lookup was done but no ident was found
45 /* --------------------------------------------------------------
46 * Note that this is the third incarnation of m_ident. The first
47 * two attempts were pretty crashy, mainly due to the fact we tried
48 * to use InspSocket/BufferedSocket to make them work. This class
49 * is ok for more heavyweight tasks, it does a lot of things behind
50 * the scenes that are not good for ident sockets and it has a huge
53 * To fix all the issues that we had in the old ident modules (many
54 * nasty race conditions that would cause segfaults etc) we have
55 * rewritten this module to use a simplified socket object based
56 * directly off EventHandler. As EventHandler only has low level
57 * readability, writeability and error events tied directly to the
58 * socket engine, this makes our lives easier as nothing happens to
59 * our ident lookup class that is outside of this module, or out-
60 * side of the control of the class. There are no timers, internal
61 * events, or such, which will cause the socket to be deleted,
62 * queued for deletion, etc. In fact, theres not even any queueing!
64 * Using this framework we have a much more stable module.
66 * A few things to note:
68 * O The only place that may *delete* an active or inactive
69 * ident socket is OnUserDisconnect in the module class.
70 * Because this is out of scope of the socket class there is
71 * no possibility that the socket may ever try to delete
74 * O Closure of the ident socket with the Close() method will
75 * not cause removal of the socket from memory or detatchment
76 * from its 'parent' User class. It will only flag it as an
77 * inactive socket in the socket engine.
79 * O Timeouts are handled in OnCheckReaady at the same time as
80 * checking if the ident socket has a result. This is done
81 * by checking if the age the of the class (its instantiation
82 * time) plus the timeout value is greater than the current time.
84 * O The ident socket is able to but should not modify its
85 * 'parent' user directly. Instead the ident socket class sets
86 * a completion flag and during the next call to OnCheckReady,
87 * the completion flag will be checked and any result copied to
88 * that user's class. This again ensures a single point of socket
89 * deletion for safer, neater code.
91 * O The code in the constructor of the ident socket is taken from
92 * BufferedSocket but majorly thinned down. It works for both
95 * O In the event that the ident socket throws a ModuleException,
96 * nothing is done. This is counted as total and complete
97 * failure to create a connection.
98 * --------------------------------------------------------------
101 class IdentRequestSocket : public EventHandler
104 LocalUser *user; /* User we are attached to */
105 std::string result; /* Holds the ident string if done */
107 bool done; /* True if lookup is finished */
109 IdentRequestSocket(LocalUser* u) : user(u)
111 age = ServerInstance->Time();
113 SetFd(socket(user->server_sa.family(), SOCK_STREAM, 0));
116 throw ModuleException("Could not create socket");
120 irc::sockets::sockaddrs bindaddr;
121 irc::sockets::sockaddrs connaddr;
123 memcpy(&bindaddr, &user->server_sa, sizeof(bindaddr));
124 memcpy(&connaddr, &user->client_sa, sizeof(connaddr));
126 if (connaddr.family() == AF_INET6)
128 bindaddr.in6.sin6_port = 0;
129 connaddr.in6.sin6_port = htons(113);
133 bindaddr.in4.sin_port = 0;
134 connaddr.in4.sin_port = htons(113);
137 /* Attempt to bind (ident requests must come from the ip the query is referring to */
138 if (SocketEngine::Bind(GetFd(), bindaddr) < 0)
141 throw ModuleException("failed to bind()");
144 SocketEngine::NonBlocking(GetFd());
146 /* Attempt connection (nonblocking) */
147 if (SocketEngine::Connect(this, connaddr) == -1 && errno != EINPROGRESS)
150 throw ModuleException("connect() failed");
153 /* Add fd to socket engine */
154 if (!SocketEngine::AddFd(this, FD_WANT_NO_READ | FD_WANT_POLL_WRITE))
157 throw ModuleException("out of fds");
161 void OnEventHandlerWrite() CXX11_OVERRIDE
163 SocketEngine::ChangeEventMask(this, FD_WANT_POLL_READ | FD_WANT_NO_WRITE);
167 /* Build request in the form 'localport,remoteport\r\n' */
169 if (user->client_sa.family() == AF_INET6)
170 req_size = snprintf(req, sizeof(req), "%d,%d\r\n",
171 ntohs(user->client_sa.in6.sin6_port), ntohs(user->server_sa.in6.sin6_port));
173 req_size = snprintf(req, sizeof(req), "%d,%d\r\n",
174 ntohs(user->client_sa.in4.sin_port), ntohs(user->server_sa.in4.sin_port));
176 /* Send failed if we didnt write the whole ident request --
177 * might as well give up if this happens!
179 if (SocketEngine::Send(this, req, req_size, 0) < req_size)
185 /* Remove ident socket from engine, and close it, but dont detatch it
186 * from its parent user class, or attempt to delete its memory.
190 ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "Close ident socket %d", GetFd());
191 SocketEngine::Close(this);
200 void OnEventHandlerRead() CXX11_OVERRIDE
202 /* We don't really need to buffer for incomplete replies here, since IDENT replies are
203 * extremely short - there is *no* sane reason it'd be in more than one packet
206 int recvresult = SocketEngine::Recv(this, ibuf, sizeof(ibuf)-1, 0);
208 /* Close (but don't delete from memory) our socket
209 * and flag as done since the ident lookup has finished
214 /* Cant possibly be a valid response shorter than 3 chars,
215 * because the shortest possible response would look like: '1,1'
220 ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "ReadResponse()");
222 /* Truncate at the first null character, but first make sure
223 * there is at least one null char (at the end of the buffer).
225 ibuf[recvresult] = '\0';
226 std::string buf(ibuf);
228 /* <2 colons: invalid
229 * 2 colons: reply is an error
230 * >3 colons: there is a colon in the ident
232 if (std::count(buf.begin(), buf.end(), ':') != 3)
235 std::string::size_type lastcolon = buf.rfind(':');
237 /* Truncate the ident at any characters we don't like, skip leading spaces */
238 for (std::string::const_iterator i = buf.begin()+lastcolon+1; i != buf.end(); ++i)
240 if (result.size() == ServerInstance->Config->Limits.IdentMax)
241 /* Ident is getting too long */
247 /* Add the next char to the result and see if it's still a valid ident,
248 * according to IsIdent(). If it isn't, then erase what we just added and
252 if (!ServerInstance->IsIdent(result))
254 result.erase(result.end()-1);
260 void OnEventHandlerError(int errornum) CXX11_OVERRIDE
266 CullResult cull() CXX11_OVERRIDE
269 return EventHandler::cull();
273 class ModuleIdent : public Module
276 unsigned int timeout;
277 bool prefixunqueried;
278 SimpleExtItem<IdentRequestSocket, stdalgo::culldeleter> socket;
281 static void PrefixIdent(LocalUser* user)
283 // Check that they haven't been prefixed already.
284 if (user->ident[0] == '~')
287 // All invalid usernames are prefixed with a tilde.
288 std::string newident(user->ident);
289 newident.insert(newident.begin(), '~');
291 // If the username is too long then truncate it.
292 if (newident.length() > ServerInstance->Config->Limits.IdentMax)
293 newident.erase(ServerInstance->Config->Limits.IdentMax);
295 // Apply the new username.
296 user->ChangeIdent(newident);
301 : socket("ident_socket", ExtensionItem::EXT_USER, this)
302 , state("ident_state", ExtensionItem::EXT_USER, this)
306 Version GetVersion() CXX11_OVERRIDE
308 return Version("Provides support for RFC1413 ident lookups", VF_VENDOR);
311 void ReadConfig(ConfigStatus& status) CXX11_OVERRIDE
313 ConfigTag* tag = ServerInstance->Config->ConfValue("ident");
314 timeout = tag->getDuration("timeout", 5, 1, 60);
315 prefixunqueried = tag->getBool("prefixunqueried");
318 void OnSetUserIP(LocalUser* user) CXX11_OVERRIDE
320 IdentRequestSocket* isock = socket.get(user);
323 // If an ident lookup request was in progress then cancel it.
328 // The ident protocol requires that clients are connecting over a protocol with ports.
329 if (user->client_sa.family() != AF_INET && user->client_sa.family() != AF_INET6)
332 // We don't want to look this up once the user has connected.
333 if (user->registered == REG_ALL)
336 ConfigTag* tag = user->MyClass->config;
337 if (!tag->getBool("useident", true))
339 state.set(user, IDENT_SKIPPED);
343 user->WriteNotice("*** Looking up your ident...");
347 isock = new IdentRequestSocket(user);
348 socket.set(user, isock);
350 catch (ModuleException &e)
352 ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "Ident exception: " + e.GetReason());
356 /* This triggers pretty regularly, we can use it in preference to
357 * creating a Timer object and especially better than creating a
358 * Timer per ident lookup!
360 ModResult OnCheckReady(LocalUser *user) CXX11_OVERRIDE
362 /* Does user have an ident socket attached at all? */
363 IdentRequestSocket* isock = socket.get(user);
366 if (prefixunqueried && state.get(user) == IDENT_SKIPPED)
369 state.set(user, IDENT_PREFIXED);
371 return MOD_RES_PASSTHRU;
374 time_t compare = isock->age + timeout;
376 /* Check for timeout of the socket */
377 if (ServerInstance->Time() >= compare)
380 state.set(user, IDENT_MISSING);
382 user->WriteNotice("*** Ident lookup timed out, using " + user->ident + " instead.");
384 else if (!isock->HasResult())
386 // time still good, no result yet... hold the registration
390 /* wooo, got a result (it will be good, or bad) */
391 else if (isock->result.empty())
393 state.set(user, IDENT_MISSING);
395 user->WriteNotice("*** Could not find your ident, using " + user->ident + " instead.");
399 state.set(user, IDENT_FOUND);
400 user->ChangeIdent(isock->result);
401 user->WriteNotice("*** Found your ident, '" + user->ident + "'");
406 return MOD_RES_PASSTHRU;
409 ModResult OnSetConnectClass(LocalUser* user, ConnectClass* myclass) CXX11_OVERRIDE
411 if (myclass->config->getBool("requireident") && state.get(user) != IDENT_FOUND)
413 return MOD_RES_PASSTHRU;
416 void OnUserConnect(LocalUser* user) CXX11_OVERRIDE
418 // Clear this as it is no longer necessary.
423 MODULE_INIT(ModuleIdent)