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 /* --------------------------------------------------------------
28 * Note that this is the third incarnation of m_ident. The first
29 * two attempts were pretty crashy, mainly due to the fact we tried
30 * to use InspSocket/BufferedSocket to make them work. This class
31 * is ok for more heavyweight tasks, it does a lot of things behind
32 * the scenes that are not good for ident sockets and it has a huge
35 * To fix all the issues that we had in the old ident modules (many
36 * nasty race conditions that would cause segfaults etc) we have
37 * rewritten this module to use a simplified socket object based
38 * directly off EventHandler. As EventHandler only has low level
39 * readability, writeability and error events tied directly to the
40 * socket engine, this makes our lives easier as nothing happens to
41 * our ident lookup class that is outside of this module, or out-
42 * side of the control of the class. There are no timers, internal
43 * events, or such, which will cause the socket to be deleted,
44 * queued for deletion, etc. In fact, theres not even any queueing!
46 * Using this framework we have a much more stable module.
48 * A few things to note:
50 * O The only place that may *delete* an active or inactive
51 * ident socket is OnUserDisconnect in the module class.
52 * Because this is out of scope of the socket class there is
53 * no possibility that the socket may ever try to delete
56 * O Closure of the ident socket with the Close() method will
57 * not cause removal of the socket from memory or detatchment
58 * from its 'parent' User class. It will only flag it as an
59 * inactive socket in the socket engine.
61 * O Timeouts are handled in OnCheckReaady at the same time as
62 * checking if the ident socket has a result. This is done
63 * by checking if the age the of the class (its instantiation
64 * time) plus the timeout value is greater than the current time.
66 * O The ident socket is able to but should not modify its
67 * 'parent' user directly. Instead the ident socket class sets
68 * a completion flag and during the next call to OnCheckReady,
69 * the completion flag will be checked and any result copied to
70 * that user's class. This again ensures a single point of socket
71 * deletion for safer, neater code.
73 * O The code in the constructor of the ident socket is taken from
74 * BufferedSocket but majorly thinned down. It works for both
77 * O In the event that the ident socket throws a ModuleException,
78 * nothing is done. This is counted as total and complete
79 * failure to create a connection.
80 * --------------------------------------------------------------
83 class IdentRequestSocket : public EventHandler
86 LocalUser *user; /* User we are attached to */
87 std::string result; /* Holds the ident string if done */
89 bool done; /* True if lookup is finished */
91 IdentRequestSocket(LocalUser* u) : user(u)
93 age = ServerInstance->Time();
95 SetFd(socket(user->server_sa.sa.sa_family, SOCK_STREAM, 0));
98 throw ModuleException("Could not create socket");
102 irc::sockets::sockaddrs bindaddr;
103 irc::sockets::sockaddrs connaddr;
105 memcpy(&bindaddr, &user->server_sa, sizeof(bindaddr));
106 memcpy(&connaddr, &user->client_sa, sizeof(connaddr));
108 if (connaddr.sa.sa_family == AF_INET6)
110 bindaddr.in6.sin6_port = 0;
111 connaddr.in6.sin6_port = htons(113);
115 bindaddr.in4.sin_port = 0;
116 connaddr.in4.sin_port = htons(113);
119 /* Attempt to bind (ident requests must come from the ip the query is referring to */
120 if (SocketEngine::Bind(GetFd(), bindaddr) < 0)
123 throw ModuleException("failed to bind()");
126 SocketEngine::NonBlocking(GetFd());
128 /* Attempt connection (nonblocking) */
129 if (SocketEngine::Connect(this, &connaddr.sa, connaddr.sa_size()) == -1 && errno != EINPROGRESS)
132 throw ModuleException("connect() failed");
135 /* Add fd to socket engine */
136 if (!SocketEngine::AddFd(this, FD_WANT_NO_READ | FD_WANT_POLL_WRITE))
139 throw ModuleException("out of fds");
145 ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "OnConnected()");
146 SocketEngine::ChangeEventMask(this, FD_WANT_POLL_READ | FD_WANT_NO_WRITE);
150 /* Build request in the form 'localport,remoteport\r\n' */
152 if (user->client_sa.sa.sa_family == AF_INET6)
153 req_size = snprintf(req, sizeof(req), "%d,%d\r\n",
154 ntohs(user->client_sa.in6.sin6_port), ntohs(user->server_sa.in6.sin6_port));
156 req_size = snprintf(req, sizeof(req), "%d,%d\r\n",
157 ntohs(user->client_sa.in4.sin_port), ntohs(user->server_sa.in4.sin_port));
159 /* Send failed if we didnt write the whole ident request --
160 * might as well give up if this happens!
162 if (SocketEngine::Send(this, req, req_size, 0) < req_size)
166 void HandleEvent(EventType et, int errornum = 0)
171 /* fd readable event, received ident response */
175 /* fd writeable event, successfully connected! */
179 /* fd error event, ohshi- */
180 ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "EVENT_ERROR");
181 /* We *must* Close() here immediately or we get a
182 * huge storm of EVENT_ERROR events!
192 /* Remove ident socket from engine, and close it, but dont detatch it
193 * from its parent user class, or attempt to delete its memory.
197 ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "Close ident socket %d", GetFd());
198 SocketEngine::Close(this);
209 /* We don't really need to buffer for incomplete replies here, since IDENT replies are
210 * extremely short - there is *no* sane reason it'd be in more than one packet
213 int recvresult = SocketEngine::Recv(this, ibuf, sizeof(ibuf)-1, 0);
215 /* Close (but don't delete from memory) our socket
216 * and flag as done since the ident lookup has finished
221 /* Cant possibly be a valid response shorter than 3 chars,
222 * because the shortest possible response would look like: '1,1'
227 ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "ReadResponse()");
229 /* Truncate at the first null character, but first make sure
230 * there is at least one null char (at the end of the buffer).
232 ibuf[recvresult] = '\0';
233 std::string buf(ibuf);
235 /* <2 colons: invalid
236 * 2 colons: reply is an error
237 * >3 colons: there is a colon in the ident
239 if (std::count(buf.begin(), buf.end(), ':') != 3)
242 std::string::size_type lastcolon = buf.rfind(':');
244 /* Truncate the ident at any characters we don't like, skip leading spaces */
245 for (std::string::const_iterator i = buf.begin()+lastcolon+1; i != buf.end(); ++i)
247 if (result.size() == ServerInstance->Config->Limits.IdentMax)
248 /* Ident is getting too long */
254 /* Add the next char to the result and see if it's still a valid ident,
255 * according to IsIdent(). If it isn't, then erase what we just added and
259 if (!ServerInstance->IsIdent(result))
261 result.erase(result.end()-1);
267 CullResult cull() CXX11_OVERRIDE
270 return EventHandler::cull();
274 class ModuleIdent : public Module
278 SimpleExtItem<IdentRequestSocket, stdalgo::culldeleter> ext;
280 ModuleIdent() : ext("ident_socket", this)
284 Version GetVersion() CXX11_OVERRIDE
286 return Version("Provides support for RFC1413 ident lookups", VF_VENDOR);
289 void ReadConfig(ConfigStatus& status) CXX11_OVERRIDE
291 ConfigTag* tag = ServerInstance->Config->ConfValue("ident");
292 RequestTimeout = tag->getInt("timeout", 5, 1);
293 NoLookupPrefix = tag->getBool("nolookupprefix", false);
296 void OnUserInit(LocalUser *user) CXX11_OVERRIDE
298 ConfigTag* tag = user->MyClass->config;
299 if (!tag->getBool("useident", true))
302 user->WriteNotice("*** Looking up your ident...");
306 IdentRequestSocket *isock = new IdentRequestSocket(user);
307 ext.set(user, isock);
309 catch (ModuleException &e)
311 ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "Ident exception: " + e.GetReason());
315 /* This triggers pretty regularly, we can use it in preference to
316 * creating a Timer object and especially better than creating a
317 * Timer per ident lookup!
319 ModResult OnCheckReady(LocalUser *user) CXX11_OVERRIDE
321 /* Does user have an ident socket attached at all? */
322 IdentRequestSocket *isock = ext.get(user);
325 if ((NoLookupPrefix) && (user->ident[0] != '~'))
326 user->ident.insert(user->ident.begin(), 1, '~');
327 return MOD_RES_PASSTHRU;
330 time_t compare = isock->age;
331 compare += RequestTimeout;
333 /* Check for timeout of the socket */
334 if (ServerInstance->Time() >= compare)
337 user->WriteNotice("*** Ident request timed out.");
339 else if (!isock->HasResult())
341 // time still good, no result yet... hold the registration
345 /* wooo, got a result (it will be good, or bad) */
346 if (isock->result.empty())
348 user->ident.insert(user->ident.begin(), 1, '~');
349 user->WriteNotice("*** Could not find your ident, using " + user->ident + " instead.");
353 user->ident = isock->result;
354 user->WriteNotice("*** Found your ident, '" + user->ident + "'");
357 user->InvalidateCache();
360 return MOD_RES_PASSTHRU;
363 ModResult OnSetConnectClass(LocalUser* user, ConnectClass* myclass) CXX11_OVERRIDE
365 if (myclass->config->getBool("requireident") && user->ident[0] == '~')
367 return MOD_RES_PASSTHRU;
371 MODULE_INIT(ModuleIdent)