1 /*
2  * InspIRCd -- Internet Relay Chat Daemon
3  *
4  *   Copyright (C) 2019 iwalkalone <iwalkalone69@gmail.com>
5  *   Copyright (C) 2019 Matt Schatz <genius3000@g3k.solutions>
6  *   Copyright (C) 2013-2016, 2018 Attila Molnar <attilamolnar@hush.com>
7  *   Copyright (C) 2013, 2018-2021 Sadie Powell <sadie@witchery.services>
8  *   Copyright (C) 2013, 2015 Adam <Adam@anope.org>
9  *   Copyright (C) 2013 Daniel Vassdal <shutter@canternet.org>
10  *   Copyright (C) 2012, 2019 Robby <robby@chatbelgie.be>
11  *   Copyright (C) 2009-2010 Daniel De Graaf <danieldg@inspircd.org>
12  *   Copyright (C) 2009 Uli Schlachter <psychon@inspircd.org>
13  *   Copyright (C) 2008-2010 Craig Edwards <brain@inspircd.org>
14  *   Copyright (C) 2008 Robin Burchell <robin+git@viroteck.net>
15  *
16  * This file is part of InspIRCd.  InspIRCd is free software: you can
17  * redistribute it and/or modify it under the terms of the GNU General Public
18  * License as published by the Free Software Foundation, version 2.
19  *
20  * This program is distributed in the hope that it will be useful, but WITHOUT
21  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
22  * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
23  * details.
24  *
25  * You should have received a copy of the GNU General Public License
26  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
27  */
28 
29 
30 #include "inspircd.h"
31 #include "xline.h"
32 #include "iohook.h"
33 
34 namespace
35 {
36 	class WriteCommonQuit : public User::ForEachNeighborHandler
37 	{
38 		ClientProtocol::Messages::Quit quitmsg;
39 		ClientProtocol::Event quitevent;
40 		ClientProtocol::Messages::Quit operquitmsg;
41 		ClientProtocol::Event operquitevent;
42 
Execute(LocalUser * user)43 		void Execute(LocalUser* user) CXX11_OVERRIDE
44 		{
45 			user->Send(user->IsOper() ? operquitevent : quitevent);
46 		}
47 
48 	 public:
WriteCommonQuit(User * user,const std::string & msg,const std::string & opermsg)49 		WriteCommonQuit(User* user, const std::string& msg, const std::string& opermsg)
50 			: quitmsg(user, msg)
51 			, quitevent(ServerInstance->GetRFCEvents().quit, quitmsg)
52 			, operquitmsg(user, opermsg)
53 			, operquitevent(ServerInstance->GetRFCEvents().quit, operquitmsg)
54 		{
55 			user->ForEachNeighbor(*this, false);
56 		}
57 	};
58 
CheckPingTimeout(LocalUser * user)59 	void CheckPingTimeout(LocalUser* user)
60 	{
61 		// Check if it is time to ping the user yet.
62 		if (ServerInstance->Time() < user->nextping)
63 			return;
64 
65 		// This user didn't answer the last ping, remove them.
66 		if (!user->lastping)
67 		{
68 			ModResult res;
69 			FIRST_MOD_RESULT(OnConnectionFail, res, (user, I_ERR_TIMEOUT));
70 			if (res == MOD_RES_ALLOW)
71 			{
72 				// A module is preventing this user from being timed out.
73 				user->lastping = 1;
74 				user->nextping = ServerInstance->Time() + user->MyClass->GetPingTime();
75 				return;
76 			}
77 
78 			time_t secs = ServerInstance->Time() - (user->nextping - user->MyClass->GetPingTime());
79 			const std::string message = "Ping timeout: " + ConvToStr(secs) + (secs != 1 ? " seconds" : " second");
80 			ServerInstance->Users.QuitUser(user, message);
81 			return;
82 		}
83 
84 		// Send a ping to the client.
85 		ClientProtocol::Messages::Ping ping;
86 		user->Send(ServerInstance->GetRFCEvents().ping, ping);
87 		user->lastping = 0;
88 		user->nextping = ServerInstance->Time() + user->MyClass->GetPingTime();
89 	}
90 
CheckRegistrationTimeout(LocalUser * user)91 	void CheckRegistrationTimeout(LocalUser* user)
92 	{
93 		if (user->GetClass() && (ServerInstance->Time() > (user->signon + user->GetClass()->GetRegTimeout())))
94 		{
95 			// Either the user did not send NICK/USER or a module blocked registration in
96 			// OnCheckReady until the client timed out.
97 			ServerInstance->Users.QuitUser(user, "Registration timeout");
98 		}
99 	}
100 
CheckModulesReady(LocalUser * user)101 	void CheckModulesReady(LocalUser* user)
102 	{
103 		ModResult res;
104 		FIRST_MOD_RESULT(OnCheckReady, res, (user));
105 		if (res == MOD_RES_PASSTHRU)
106 		{
107 			// User has sent NICK/USER and modules are ready.
108 			user->FullConnect();
109 			return;
110 		}
111 
112 		// If the user has been quit in OnCheckReady then we shouldn't quit
113 		// them again for having a registration timeout.
114 		if (!user->quitting)
115 			CheckRegistrationTimeout(user);
116 	}
117 }
118 
UserManager()119 UserManager::UserManager()
120 	: already_sent_id(0)
121 	, unregistered_count(0)
122 {
123 }
124 
~UserManager()125 UserManager::~UserManager()
126 {
127 	for (user_hash::iterator i = clientlist.begin(); i != clientlist.end(); ++i)
128 	{
129 		delete i->second;
130 	}
131 }
132 
AddUser(int socket,ListenSocket * via,irc::sockets::sockaddrs * client,irc::sockets::sockaddrs * server)133 void UserManager::AddUser(int socket, ListenSocket* via, irc::sockets::sockaddrs* client, irc::sockets::sockaddrs* server)
134 {
135 	// User constructor allocates a new UUID for the user and inserts it into the uuidlist
136 	LocalUser* const New = new LocalUser(socket, client, server);
137 	UserIOHandler* eh = &New->eh;
138 
139 	ServerInstance->Logs->Log("USERS", LOG_DEBUG, "New user fd: %d", socket);
140 
141 	this->unregistered_count++;
142 	this->clientlist[New->nick] = New;
143 	this->AddClone(New);
144 	this->local_users.push_front(New);
145 	FOREACH_MOD(OnUserInit, (New));
146 
147 	if (!SocketEngine::AddFd(eh, FD_WANT_FAST_READ | FD_WANT_EDGE_WRITE))
148 	{
149 		ServerInstance->Logs->Log("USERS", LOG_DEBUG, "Internal error on new connection");
150 		this->QuitUser(New, "Internal error handling connection");
151 		return;
152 	}
153 
154 	// If this listener has an IO hook provider set then tell it about the connection
155 	for (ListenSocket::IOHookProvList::iterator i = via->iohookprovs.begin(); i != via->iohookprovs.end(); ++i)
156 	{
157 		ListenSocket::IOHookProvRef& iohookprovref = *i;
158 		if (!iohookprovref)
159 		{
160 			if (!iohookprovref.GetProvider().empty())
161 			{
162 				ServerInstance->Logs->Log("USERS", LOG_DEBUG, "Non-existent I/O hook '%s' in <bind:%s> tag at %s",
163 					iohookprovref.GetProvider().c_str(),
164 					i == via->iohookprovs.begin() ? "hook" : "sslprofile",
165 					via->bind_tag->getTagLocation().c_str());
166 				this->QuitUser(New, "Internal error handling connection");
167 				return;
168 			}
169 			continue;
170 		}
171 
172 		iohookprovref->OnAccept(eh, client, server);
173 
174 		// IOHook could have encountered a fatal error, e.g. if the TLS ClientHello
175 		// was already in the queue and there was no common TLS version.
176 		if (!eh->getError().empty())
177 		{
178 			QuitUser(New, eh->getError());
179 			return;
180 		}
181 	}
182 
183 	if (this->local_users.size() > ServerInstance->Config->SoftLimit)
184 	{
185 		ServerInstance->SNO->WriteToSnoMask('a', "Warning: softlimit value has been reached: %d clients", ServerInstance->Config->SoftLimit);
186 		this->QuitUser(New,"No more connections allowed");
187 		return;
188 	}
189 
190 	// First class check. We do this again in LocalUser::FullConnect() after DNS is done, and NICK/USER is received.
191 	New->SetClass();
192 	// If the user doesn't have an acceptable connect class CheckClass() quits them
193 	New->CheckClass(ServerInstance->Config->CCOnConnect);
194 	if (New->quitting)
195 		return;
196 
197 	/*
198 	 * even with bancache, we still have to keep User::exempt current.
199 	 * besides that, if we get a positive bancache hit, we still won't fuck
200 	 * them over if they are exempt. -- w00t
201 	 */
202 	New->exempt = (ServerInstance->XLines->MatchesLine("E",New) != NULL);
203 
204 	BanCacheHit* const b = ServerInstance->BanCache.GetHit(New->GetIPString());
205 	if (b)
206 	{
207 		if (!b->Type.empty() && !New->exempt)
208 		{
209 			/* user banned */
210 			ServerInstance->Logs->Log("BANCACHE", LOG_DEBUG, "BanCache: Positive hit for " + New->GetIPString());
211 			if (!ServerInstance->Config->XLineMessage.empty())
212 				New->WriteNumeric(ERR_YOUREBANNEDCREEP, ServerInstance->Config->XLineMessage);
213 
214 			if (ServerInstance->Config->HideBans)
215 				this->QuitUser(New, b->Type + "-lined", &b->Reason);
216 			else
217 				this->QuitUser(New, b->Reason);
218 			return;
219 		}
220 		else
221 		{
222 			ServerInstance->Logs->Log("BANCACHE", LOG_DEBUG, "BanCache: Negative hit for " + New->GetIPString());
223 		}
224 	}
225 	else
226 	{
227 		if (!New->exempt)
228 		{
229 			XLine* r = ServerInstance->XLines->MatchesLine("Z",New);
230 
231 			if (r)
232 			{
233 				r->Apply(New);
234 				return;
235 			}
236 		}
237 	}
238 
239 	if (ServerInstance->Config->RawLog)
240 		New->WriteNotice("*** Raw I/O logging is enabled on this server. All messages, passwords, and commands are being recorded.");
241 
242 	FOREACH_MOD(OnSetUserIP, (New));
243 	if (!New->quitting)
244 		FOREACH_MOD(OnUserPostInit, (New));
245 }
246 
QuitUser(User * user,const std::string & quitmessage,const std::string * operquitmessage)247 void UserManager::QuitUser(User* user, const std::string& quitmessage, const std::string* operquitmessage)
248 {
249 	if (user->quitting)
250 	{
251 		ServerInstance->Logs->Log("USERS", LOG_DEFAULT, "ERROR: Tried to quit quitting user: " + user->nick);
252 		return;
253 	}
254 
255 	if (IS_SERVER(user))
256 	{
257 		ServerInstance->Logs->Log("USERS", LOG_DEFAULT, "ERROR: Tried to quit server user: " + user->nick);
258 		return;
259 	}
260 
261 	std::string quitmsg(quitmessage);
262 	std::string operquitmsg;
263 	if (operquitmessage)
264 		operquitmsg.assign(*operquitmessage);
265 
266 	LocalUser* const localuser = IS_LOCAL(user);
267 	if (localuser)
268 	{
269 		ModResult MOD_RESULT;
270 		FIRST_MOD_RESULT(OnUserPreQuit, MOD_RESULT, (localuser, quitmsg, operquitmsg));
271 		if (MOD_RESULT == MOD_RES_DENY)
272 			return;
273 	}
274 
275 	if (quitmsg.length() > ServerInstance->Config->Limits.MaxQuit)
276 		quitmsg.erase(ServerInstance->Config->Limits.MaxQuit + 1);
277 
278 	if (operquitmsg.empty())
279 		operquitmsg.assign(quitmsg);
280 	else if (operquitmsg.length() > ServerInstance->Config->Limits.MaxQuit)
281 		operquitmsg.erase(ServerInstance->Config->Limits.MaxQuit + 1);
282 
283 	user->quitting = true;
284 	ServerInstance->Logs->Log("USERS", LOG_DEBUG, "QuitUser: %s=%s '%s'", user->uuid.c_str(), user->nick.c_str(), quitmessage.c_str());
285 	if (localuser)
286 	{
287 		ClientProtocol::Messages::Error errormsg(InspIRCd::Format("Closing link: (%s@%s) [%s]", user->ident.c_str(), user->GetRealHost().c_str(), operquitmsg.c_str()));
288 		localuser->Send(ServerInstance->GetRFCEvents().error, errormsg);
289 	}
290 
291 	ServerInstance->GlobalCulls.AddItem(user);
292 
293 	if (user->registered == REG_ALL)
294 	{
295 		FOREACH_MOD(OnUserQuit, (user, quitmsg, operquitmsg));
296 		WriteCommonQuit(user, quitmsg, operquitmsg);
297 	}
298 	else
299 		unregistered_count--;
300 
301 	if (IS_LOCAL(user))
302 	{
303 		LocalUser* lu = IS_LOCAL(user);
304 		FOREACH_MOD(OnUserDisconnect, (lu));
305 		lu->eh.Close();
306 
307 		if (lu->registered == REG_ALL)
308 			ServerInstance->SNO->WriteToSnoMask('q',"Client exiting: %s (%s) [%s]", user->GetFullRealHost().c_str(), user->GetIPString().c_str(), operquitmsg.c_str());
309 		local_users.erase(lu);
310 	}
311 
312 	if (!clientlist.erase(user->nick))
313 		ServerInstance->Logs->Log("USERS", LOG_DEFAULT, "ERROR: Nick not found in clientlist, cannot remove: " + user->nick);
314 
315 	uuidlist.erase(user->uuid);
316 	user->PurgeEmptyChannels();
317 	user->UnOper();
318 }
319 
AddClone(User * user)320 void UserManager::AddClone(User* user)
321 {
322 	CloneCounts& counts = clonemap[user->GetCIDRMask()];
323 	counts.global++;
324 	if (IS_LOCAL(user))
325 		counts.local++;
326 }
327 
RemoveCloneCounts(User * user)328 void UserManager::RemoveCloneCounts(User *user)
329 {
330 	CloneMap::iterator it = clonemap.find(user->GetCIDRMask());
331 	if (it != clonemap.end())
332 	{
333 		CloneCounts& counts = it->second;
334 		counts.global--;
335 		if (counts.global == 0)
336 		{
337 			// No more users from this IP, remove entry from the map
338 			clonemap.erase(it);
339 			return;
340 		}
341 
342 		if (IS_LOCAL(user))
343 			counts.local--;
344 	}
345 }
346 
RehashCloneCounts()347 void UserManager::RehashCloneCounts()
348 {
349 	clonemap.clear();
350 
351 	const user_hash& hash = ServerInstance->Users.GetUsers();
352 	for (user_hash::const_iterator i = hash.begin(); i != hash.end(); ++i)
353 	{
354 		User* u = i->second;
355 		AddClone(u);
356 	}
357 }
358 
GetCloneCounts(User * user) const359 const UserManager::CloneCounts& UserManager::GetCloneCounts(User* user) const
360 {
361 	CloneMap::const_iterator it = clonemap.find(user->GetCIDRMask());
362 	if (it != clonemap.end())
363 		return it->second;
364 	else
365 		return zeroclonecounts;
366 }
367 
ServerNoticeAll(const char * text,...)368 void UserManager::ServerNoticeAll(const char* text, ...)
369 {
370 	std::string message;
371 	VAFORMAT(message, text, text);
372 	ClientProtocol::Messages::Privmsg msg(ClientProtocol::Messages::Privmsg::nocopy, ServerInstance->FakeClient, ServerInstance->Config->GetServerName(), message, MSG_NOTICE);
373 	ClientProtocol::Event msgevent(ServerInstance->GetRFCEvents().privmsg, msg);
374 
375 	for (LocalList::const_iterator i = local_users.begin(); i != local_users.end(); ++i)
376 	{
377 		LocalUser* user = *i;
378 		user->Send(msgevent);
379 	}
380 }
381 
382 /**
383  * This function is called once a second from the mainloop.
384  * It is intended to do background checking on all the users, e.g. do
385  * ping checks, registration timeouts, etc.
386  */
DoBackgroundUserStuff()387 void UserManager::DoBackgroundUserStuff()
388 {
389 	for (LocalList::iterator i = local_users.begin(); i != local_users.end(); )
390 	{
391 		// It's possible that we quit the user below due to ping timeout etc. and QuitUser() removes it from the list
392 		LocalUser* curr = *i;
393 		++i;
394 
395 		if (curr->CommandFloodPenalty || curr->eh.getSendQSize())
396 		{
397 			unsigned int rate = curr->MyClass->GetCommandRate();
398 			if (curr->CommandFloodPenalty > rate)
399 				curr->CommandFloodPenalty -= rate;
400 			else
401 				curr->CommandFloodPenalty = 0;
402 			curr->eh.OnDataReady();
403 		}
404 
405 		switch (curr->registered)
406 		{
407 			case REG_ALL:
408 				CheckPingTimeout(curr);
409 				break;
410 
411 			case REG_NICKUSER:
412 				CheckModulesReady(curr);
413 				break;
414 
415 			default:
416 				CheckRegistrationTimeout(curr);
417 				break;
418 		}
419 	}
420 }
421 
NextAlreadySentId()422 already_sent_t UserManager::NextAlreadySentId()
423 {
424 	if (++already_sent_id == 0)
425 	{
426 		// Wrapped around, reset the already_sent ids of all users
427 		already_sent_id = 1;
428 		for (LocalList::iterator i = local_users.begin(); i != local_users.end(); ++i)
429 		{
430 			LocalUser* user = *i;
431 			user->already_sent = 0;
432 		}
433 	}
434 	return already_sent_id;
435 }
436