1 /* +------------------------------------+
2 * | Inspire Internet Relay Chat Daemon |
3 * +------------------------------------+
5 * InspIRCd: (C) 2002-2008 InspIRCd Development Team
6 * See: http://www.inspircd.org/wiki/index.php/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 */
83 IdentRequestSocket(InspIRCd *Server, User* u, const std::string &bindip) : user(u), ServerInstance(Server), result(u->ident)
87 /* Does this look like a v6 ip address? */
89 if ((bindip.empty()) || bindip.find(':') != std::string::npos)
93 SetFd(socket(AF_INET6, SOCK_STREAM, 0));
96 SetFd(socket(AF_INET, SOCK_STREAM, 0));
99 throw ModuleException("Could not create socket");
103 /* We allocate two of these because sizeof(sockaddr_in6) > sizeof(sockaddr_in) */
104 sockaddr* s = new sockaddr[2];
105 sockaddr* addr = new sockaddr[2];
108 /* Horrid icky nasty ugly berkely socket crap. */
113 if (inet_pton(AF_INET6, user->GetIPString(), &addy) > 0)
115 ((sockaddr_in6*)addr)->sin6_family = AF_INET6;
116 memcpy(&((sockaddr_in6*)addr)->sin6_addr, &addy, sizeof(addy));
117 ((sockaddr_in6*)addr)->sin6_port = htons(113);
118 size = sizeof(sockaddr_in6);
119 inet_pton(AF_INET6, bindip.c_str(), &n);
120 memcpy(&((sockaddr_in6*)s)->sin6_addr, &n, sizeof(sockaddr_in6));
121 ((sockaddr_in6*)s)->sin6_port = 0;
122 ((sockaddr_in6*)s)->sin6_family = AF_INET6;
130 if (inet_aton(user->GetIPString(), &addy) > 0)
132 ((sockaddr_in*)addr)->sin_family = AF_INET;
133 ((sockaddr_in*)addr)->sin_addr = addy;
134 ((sockaddr_in*)addr)->sin_port = htons(113);
135 size = sizeof(sockaddr_in);
136 inet_aton(bindip.c_str(), &n);
137 ((sockaddr_in*)s)->sin_addr = n;
138 ((sockaddr_in*)s)->sin_port = 0;
139 ((sockaddr_in*)s)->sin_family = AF_INET;
143 /* Attempt to bind (ident requests must come from the ip the query is referring to */
144 if (ServerInstance->SE->Bind(GetFd(), s, size) < 0)
149 throw ModuleException("failed to bind()");
153 ServerInstance->SE->NonBlocking(GetFd());
155 /* Attempt connection (nonblocking) */
156 if (ServerInstance->SE->Connect(this, (sockaddr*)addr, size) == -1 && errno != EINPROGRESS)
160 throw ModuleException("connect() failed");
165 /* Add fd to socket engine */
166 if (!ServerInstance->SE->AddFd(this))
169 throw ModuleException("out of fds");
172 /* Important: We set WantWrite immediately after connect()
173 * because a successful connection will trigger a writability event
175 ServerInstance->SE->WantWrite(this);
178 virtual void OnConnected()
180 ServerInstance->Logs->Log("m_ident",DEBUG,"OnConnected()");
182 /* Both sockaddr_in and sockaddr_in6 can be safely casted to sockaddr, especially since the
183 * only members we use are in a part of the struct that should always be identical (at the
186 sockaddr_in laddr, raddr;
188 sockaddr_in6 laddr, raddr;
191 socklen_t laddrsz = sizeof(laddr);
192 socklen_t raddrsz = sizeof(raddr);
194 if ((getsockname(user->GetFd(), (sockaddr*) &laddr, &laddrsz) != 0) || (getpeername(user->GetFd(), (sockaddr*) &raddr, &raddrsz) != 0))
202 /* Build request in the form 'localport,remoteport\r\n' */
204 int req_size = snprintf(req, sizeof(req), "%d,%d\r\n", ntohs(raddr.sin_port), ntohs(laddr.sin_port));
206 int req_size = snprintf(req, sizeof(req), "%d,%d\r\n", ntohs(raddr.sin6_port), ntohs(laddr.sin6_port));
209 /* Send failed if we didnt write the whole ident request --
210 * might as well give up if this happens!
212 if (ServerInstance->SE->Send(this, req, req_size, 0) < req_size)
216 virtual void HandleEvent(EventType et, int errornum = 0)
221 /* fd readable event, received ident response */
225 /* fd writeable event, successfully connected! */
229 /* fd error event, ohshi- */
230 ServerInstance->Logs->Log("m_ident",DEBUG,"EVENT_ERROR");
231 /* We *must* Close() here immediately or we get a
232 * huge storm of EVENT_ERROR events!
242 /* Remove ident socket from engine, and close it, but dont detatch it
243 * from its parent user class, or attempt to delete its memory.
247 ServerInstance->Logs->Log("m_ident",DEBUG,"Close ident socket %d", GetFd());
248 ServerInstance->SE->DelFd(this);
249 ServerInstance->SE->Close(GetFd());
250 ServerInstance->SE->Shutdown(GetFd(), SHUT_WR);
260 /* Note: if the lookup succeeded, will contain 'ident', otherwise
261 * will contain '~ident'. Use *GetResult() to determine lookup success.
263 const char* GetResult()
265 return result.c_str();
270 /* We don't really need to buffer for incomplete replies here, since IDENT replies are
271 * extremely short - there is *no* sane reason it'd be in more than one packet
274 int recvresult = ServerInstance->SE->Recv(this, ibuf, MAXBUF-1, 0);
276 /* Cant possibly be a valid response shorter than 3 chars,
277 * because the shortest possible response would look like: '1,1'
286 ServerInstance->Logs->Log("m_ident",DEBUG,"ReadResponse()");
288 irc::sepstream sep(ibuf, ':');
290 for (int i = 0; sep.GetToken(token); i++)
292 /* We only really care about the 4th portion */
298 /* Truncate the ident at any characters we don't like, skip leading spaces */
300 for (const char *j = token.c_str(); *j && (k < ServerInstance->Config->Limits.IdentMax + 1); j++)
305 /* Rules taken from InspIRCd::IsIdent */
306 if (((*j >= 'A') && (*j <= '}')) || ((*j >= '0') && (*j <= '9')) || (*j == '-') || (*j == '.'))
315 /* Re-check with IsIdent, in case that changes and this doesn't (paranoia!) */
316 if (!ident.empty() && ServerInstance->IsIdent(ident.c_str()))
324 /* Close (but dont delete from memory) our socket
333 class ModuleIdent : public Module
339 ModuleIdent(InspIRCd *Me) : Module(Me)
341 Conf = new ConfigReader(ServerInstance);
343 Implementation eventlist[] = { I_OnRehash, I_OnUserRegister, I_OnCheckReady, I_OnCleanup, I_OnUserDisconnect };
344 ServerInstance->Modules->Attach(eventlist, this, 5);
352 virtual Version GetVersion()
354 return Version("$Id$", VF_VENDOR, API_VERSION);
357 virtual void OnRehash(User *user, const std::string ¶m)
360 Conf = new ConfigReader(ServerInstance);
362 RequestTimeout = Conf->ReadInteger("ident", "timeout", 0, true);
367 virtual int OnUserRegister(User *user)
369 for (int j = 0; j < Conf->Enumerate("connect"); j++)
371 std::string hostn = Conf->ReadValue("connect","allow",j);
372 /* XXX: Fixme: does not respect port, limit, etc */
373 if ((InspIRCd::MatchCIDR(user->GetIPString(),hostn)) || (InspIRCd::Match(user->host,hostn)))
375 bool useident = Conf->ReadFlag("connect", "useident", j);
382 /* User::ident is currently the username field from USER; with m_ident loaded, that
383 * should be preceded by a ~. The field is actually IdentMax+2 characters wide. */
384 if (user->ident.length() > ServerInstance->Config->Limits.IdentMax + 1)
385 user->ident.assign(user->ident, 0, ServerInstance->Config->Limits.IdentMax);
386 user->ident.insert(0, "~");
388 user->WriteServ("NOTICE Auth :*** Looking up your ident...");
390 // Get the IP that the user is connected to, and bind to that for the outgoing connection
396 socklen_t laddrsz = sizeof(laddr);
398 if (getsockname(user->GetFd(), (sockaddr*) &laddr, &laddrsz) != 0)
400 user->WriteServ("NOTICE Auth :*** Could not find your ident, using %s instead.", user->ident.c_str());
405 const char *ip = inet_ntoa(laddr.sin_addr);
407 char ip[INET6_ADDRSTRLEN + 1];
408 inet_ntop(laddr.sin6_family, &laddr.sin6_addr, ip, INET6_ADDRSTRLEN);
411 IdentRequestSocket *isock = NULL;
414 isock = new IdentRequestSocket(ServerInstance, user, ip);
416 catch (ModuleException &e)
418 ServerInstance->Logs->Log("m_ident",DEBUG,"Ident exception: %s", e.GetReason());
422 user->Extend("ident_socket", isock);
426 /* This triggers pretty regularly, we can use it in preference to
427 * creating a Timer object and especially better than creating a
428 * Timer per ident lookup!
430 virtual bool OnCheckReady(User *user)
432 /* Does user have an ident socket attached at all? */
433 IdentRequestSocket *isock = NULL;
434 if (!user->GetExt("ident_socket", isock))
436 ServerInstance->Logs->Log("m_ident",DEBUG, "No ident socket :(");
440 ServerInstance->Logs->Log("m_ident",DEBUG, "Has ident_socket");
442 time_t compare = isock->age;
443 compare += RequestTimeout;
445 /* Check for timeout of the socket */
446 if (ServerInstance->Time() >= compare)
449 user->WriteServ("NOTICE Auth :*** Ident request timed out.");
450 ServerInstance->Logs->Log("m_ident",DEBUG, "Timeout");
451 /* The user isnt actually disconnecting,
452 * we call this to clean up the user
454 OnUserDisconnect(user);
458 /* Got a result yet? */
459 if (!isock->HasResult())
461 ServerInstance->Logs->Log("m_ident",DEBUG, "No result yet");
465 ServerInstance->Logs->Log("m_ident",DEBUG, "Yay, result!");
467 /* wooo, got a result (it will be good, or bad) */
468 if (*(isock->GetResult()) != '~')
469 user->WriteServ("NOTICE Auth :*** Found your ident, '%s'", isock->GetResult());
471 user->WriteServ("NOTICE Auth :*** Could not find your ident, using %s instead.", isock->GetResult());
473 /* Copy the ident string to the user */
474 user->ident.assign(isock->GetResult(), 0, ServerInstance->Config->Limits.IdentMax + 1);
476 /* The user isnt actually disconnecting, we call this to clean up the user */
477 OnUserDisconnect(user);
481 virtual void OnCleanup(int target_type, void *item)
483 /* Module unloading, tidy up users */
484 if (target_type == TYPE_USER)
485 OnUserDisconnect((User*)item);
488 virtual void OnUserDisconnect(User *user)
490 /* User disconnect (generic socket detatch event) */
491 IdentRequestSocket *isock = NULL;
492 if (user->GetExt("ident_socket", isock))
496 user->Shrink("ident_socket");
501 MODULE_INIT(ModuleIdent)