2 * InspIRCd -- Internet Relay Chat Daemon
4 * Copyright (C) 2017-2019 B00mX0r <b00mx0r@aureus.pw>
5 * Copyright (C) 2017 Sheogorath <sheogorath@shivering-isles.com>
6 * Copyright (C) 2016 Adam <Adam@anope.org>
7 * Copyright (C) 2014 Thomas Fargeix <t.fargeix@gmail.com>
8 * Copyright (C) 2013, 2018 Attila Molnar <attilamolnar@hush.com>
9 * Copyright (C) 2013, 2016-2020 Sadie Powell <sadie@witchery.services>
10 * Copyright (C) 2012 Robby <robby@chatbelgie.be>
11 * Copyright (C) 2011 jackmcbarn <jackmcbarn@inspircd.org>
12 * Copyright (C) 2009-2010 Daniel De Graaf <danieldg@inspircd.org>
13 * Copyright (C) 2007-2009 Robin Burchell <robin+git@viroteck.net>
14 * Copyright (C) 2007-2008, 2010 Craig Edwards <brain@inspircd.org>
15 * Copyright (C) 2007-2008 Dennis Friis <peavey@inspircd.org>
16 * Copyright (C) 2006 Oliver Lupton <om@inspircd.org>
18 * This file is part of InspIRCd. InspIRCd is free software: you can
19 * redistribute it and/or modify it under the terms of the GNU General Public
20 * License as published by the Free Software Foundation, version 2.
22 * This program is distributed in the hope that it will be useful, but WITHOUT
23 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
24 * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
27 * You should have received a copy of the GNU General Public License
28 * along with this program. If not, see <http://www.gnu.org/licenses/>.
33 #include "modules/hash.h"
37 /** 2.0 cloak of "half" of the hostname plus the full IP hash */
40 /** 2.0 cloak of IP hash, split at 2 common CIDR range points */
44 // lowercase-only encoding similar to base64, used for hash output
45 static const char base32[] = "0123456789abcdefghijklmnopqrstuv";
47 // The minimum length of a cloak key.
48 static const size_t minkeylen = 30;
52 // The method used for cloaking users.
55 // The number of parts of the hostname shown when using half cloaking.
56 unsigned int domainparts;
58 // Whether to ignore the case of a hostname when cloaking it.
61 // The secret used for generating cloaks.
64 // The prefix for cloaks (e.g. MyNet-).
67 // The suffix for IP cloaks (e.g. .IP).
70 CloakInfo(CloakMode Mode, const std::string& Key, const std::string& Prefix, const std::string& Suffix, bool IgnoreCase, unsigned int DomainParts = 0)
72 , domainparts(DomainParts)
73 , ignorecase(IgnoreCase)
81 typedef std::vector<std::string> CloakList;
83 /** Handles user mode +x
85 class CloakUser : public ModeHandler
89 SimpleExtItem<CloakList> ext;
90 std::string debounce_uid;
94 CloakUser(Module* source)
95 : ModeHandler(source, "cloak", 'x', PARAM_NONE, MODETYPE_USER)
97 , ext("cloaked_host", ExtensionItem::EXT_USER, source)
103 ModeAction OnModeChange(User* source, User* dest, Channel* channel, std::string& parameter, bool adding) CXX11_OVERRIDE
105 LocalUser* user = IS_LOCAL(dest);
107 /* For remote clients, we don't take any action, we just allow it.
108 * The local server where they are will set their cloak instead.
109 * This is fine, as we will receive it later.
113 // Remote setters broadcast mode before host while local setters do the opposite, so this takes that into account
114 active = IS_LOCAL(source) ? adding : !adding;
115 dest->SetMode(this, adding);
116 return MODEACTION_ALLOW;
119 if (user->uuid == debounce_uid && debounce_ts == ServerInstance->Time())
121 // prevent spamming using /mode user +x-x+x-x+x-x
122 if (++debounce_count > 2)
123 return MODEACTION_DENY;
127 debounce_uid = user->uuid;
129 debounce_ts = ServerInstance->Time();
132 if (adding == user->IsModeSet(this))
133 return MODEACTION_DENY;
135 /* don't allow this user to spam modechanges */
137 user->CommandFloodPenalty += 5000;
141 // assume this is more correct
142 if (user->registered != REG_ALL && user->GetRealHost() != user->GetDisplayedHost())
143 return MODEACTION_DENY;
145 CloakList* cloaks = ext.get(user);
148 /* Force creation of missing cloak */
151 creator->OnUserConnect(user);
152 cloaks = ext.get(user);
154 catch (CoreException& modexcept)
156 ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "Exception caught when generating cloak: " + modexcept.GetReason());
157 return MODEACTION_DENY;
161 // If we have a cloak then set the hostname.
162 if (cloaks && !cloaks->empty())
164 user->ChangeDisplayedHost(cloaks->front());
165 user->SetMode(this, true);
166 return MODEACTION_ALLOW;
169 return MODEACTION_DENY;
173 /* User is removing the mode, so restore their real host
174 * and make it match the displayed one.
176 user->SetMode(this, false);
177 user->ChangeDisplayedHost(user->GetRealHost().c_str());
178 return MODEACTION_ALLOW;
183 class CommandCloak : public Command
186 CommandCloak(Module* Creator) : Command(Creator, "CLOAK", 1)
192 CmdResult Handle(User* user, const Params& parameters) CXX11_OVERRIDE;
195 class ModuleCloaking : public Module
200 std::vector<CloakInfo> cloaks;
201 dynamic_reference<HashProvider> Hash;
206 , Hash(this, "hash/md5")
210 /** Takes a domain name and retrieves the subdomain which should be visible.
211 * This is usually the last \p domainparts labels but if not enough are
212 * present then all but the most specific label are used. If the domain name
213 * consists of one label only then none are used.
215 * Here are some examples for how domain names will be shortened assuming
216 * \p domainparts is set to the default of 3.
218 * "this.is.an.example.com" => ".an.example.com"
219 * "an.example.com" => ".example.com"
220 * "example.com" => ".com"
223 * @param host The hostname to cloak.
224 * @param domainparts The number of domain labels that should be visible.
225 * @return The visible segment of the hostname.
227 std::string VisibleDomainParts(const std::string& host, unsigned int domainparts)
229 // The position at which we found the last dot.
230 std::string::const_reverse_iterator dotpos;
232 // The number of dots we have seen so far.
233 unsigned int seendots = 0;
235 for (std::string::const_reverse_iterator iter = host.rbegin(); iter != host.rend(); ++iter)
240 // We have found a dot!
244 // Do we have enough segments to stop?
245 if (seendots >= domainparts)
249 // We only returns a domain part if more than one label is
250 // present. See above for a full explanation.
253 return std::string(dotpos.base() - 1, host.end());
257 * 2.0-style cloaking function
258 * @param item The item to cloak (part of an IP or hostname)
259 * @param id A unique ID for this type of item (to make it unique if the item matches)
260 * @param len The length of the output. Maximum for MD5 is 16 characters.
262 std::string SegmentCloak(const CloakInfo& info, const std::string& item, char id, size_t len)
265 input.reserve(info.key.length() + 3 + item.length());
267 input.append(info.key);
268 input.append(1, '\0'); // null does not terminate a C++ string
270 std::transform(item.begin(), item.end(), std::back_inserter(input), ::tolower);
274 std::string rv = Hash->GenerateRaw(input).substr(0,len);
275 for(size_t i = 0; i < len; i++)
277 // this discards 3 bits per byte. We have an
278 // overabundance of bits in the hash output, doesn't
279 // matter which ones we are discarding.
280 rv[i] = base32[rv[i] & 0x1F];
285 std::string SegmentIP(const CloakInfo& info, const irc::sockets::sockaddrs& ip, bool full)
288 size_t hop1, hop2, hop3;
291 if (ip.family() == AF_INET6)
293 bindata = std::string((const char*)ip.in6.sin6_addr.s6_addr, 16);
299 // pfx s1.s2.s3. (xxxx.xxxx or s4) sfx
301 rv.reserve(info.prefix.length() + 26 + info.suffix.length());
305 bindata = std::string((const char*)&ip.in4.sin_addr, 4);
310 // pfx s1.s2. (xxx.xxx or s3) sfx
311 rv.reserve(info.prefix.length() + 15 + info.suffix.length());
314 rv.append(info.prefix);
315 rv.append(SegmentCloak(info, bindata, 10, len1));
318 rv.append(SegmentCloak(info, bindata, 11, len2));
323 rv.append(SegmentCloak(info, bindata, 12, len2));
330 rv.append(SegmentCloak(info, bindata, 13, 6));
331 rv.append(info.suffix);
335 if (ip.family() == AF_INET6)
337 rv.append(InspIRCd::Format(".%02x%02x.%02x%02x%s",
338 ip.in6.sin6_addr.s6_addr[2], ip.in6.sin6_addr.s6_addr[3],
339 ip.in6.sin6_addr.s6_addr[0], ip.in6.sin6_addr.s6_addr[1], info.suffix.c_str()));
343 const unsigned char* ip4 = (const unsigned char*)&ip.in4.sin_addr;
344 rv.append(InspIRCd::Format(".%d.%d%s", ip4[1], ip4[0], info.suffix.c_str()));
350 ModResult OnCheckBan(User* user, Channel* chan, const std::string& mask) CXX11_OVERRIDE
352 LocalUser* lu = IS_LOCAL(user);
354 return MOD_RES_PASSTHRU;
356 // Force the creation of cloaks if not already set.
359 // If the user has no cloaks (i.e. UNIX socket) then we do nothing here.
360 CloakList* cloaklist = cu.ext.get(user);
361 if (!cloaklist || cloaklist->empty())
362 return MOD_RES_PASSTHRU;
364 // Check if they have a cloaked host but are not using it.
365 for (CloakList::const_iterator iter = cloaklist->begin(); iter != cloaklist->end(); ++iter)
367 const std::string& cloak = *iter;
368 if (cloak != user->GetDisplayedHost())
370 const std::string cloakMask = user->nick + "!" + user->ident + "@" + cloak;
371 if (InspIRCd::Match(cloakMask, mask))
375 return MOD_RES_PASSTHRU;
378 void Prioritize() CXX11_OVERRIDE
380 /* Needs to be after m_banexception etc. */
381 ServerInstance->Modules->SetPriority(this, I_OnCheckBan, PRIORITY_LAST);
384 // this unsets umode +x on every host change. If we are actually doing a +x
385 // mode change, we will call SetMode back to true AFTER the host change is done.
386 void OnChangeHost(User* u, const std::string& host) CXX11_OVERRIDE
388 if (u->IsModeSet(cu) && !cu.active)
390 u->SetMode(cu, false);
392 LocalUser* luser = IS_LOCAL(u);
396 Modes::ChangeList modechangelist;
397 modechangelist.push_remove(&cu);
398 ClientProtocol::Events::Mode modeevent(ServerInstance->FakeClient, NULL, u, modechangelist);
399 luser->Send(modeevent);
404 Version GetVersion() CXX11_OVERRIDE
406 std::string testcloak = "broken";
407 if (Hash && !cloaks.empty())
409 const CloakInfo& info = cloaks.front();
412 case MODE_HALF_CLOAK:
413 // Use old cloaking verification to stay compatible with 2.0
414 // But verify domainparts and ignorecase when use 3.0-only features
415 if (info.domainparts == 3 && !info.ignorecase)
416 testcloak = info.prefix + SegmentCloak(info, "*", 3, 8) + info.suffix;
419 irc::sockets::sockaddrs sa;
420 testcloak = GenCloak(info, sa, "", testcloak + ConvToStr(info.domainparts)) + (info.ignorecase ? "-ci" : "");
424 testcloak = info.prefix + SegmentCloak(info, "*", 4, 8) + info.suffix + (info.ignorecase ? "-ci" : "");
427 return Version("Adds user mode x (cloak) which allows user hostnames to be hidden.", VF_COMMON|VF_VENDOR, testcloak);
430 void ReadConfig(ConfigStatus& status) CXX11_OVERRIDE
432 ConfigTagList tags = ServerInstance->Config->ConfTags("cloak");
433 if (tags.first == tags.second)
434 throw ModuleException("You have loaded the cloaking module but not configured any <cloak> tags!");
436 std::vector<CloakInfo> newcloaks;
437 for (ConfigIter i = tags.first; i != tags.second; ++i)
439 ConfigTag* tag = i->second;
441 // Ensure that we have the <cloak:key> parameter.
442 const std::string key = tag->getString("key");
444 throw ModuleException("You have not defined a cloaking key. Define <cloak:key> as a " + ConvToStr(minkeylen) + "+ character network-wide secret, at " + tag->getTagLocation());
446 // If we are the first cloak method then mandate a strong key.
447 if (i == tags.first && key.length() < minkeylen)
448 throw ModuleException("Your cloaking key is not secure. It should be at least " + ConvToStr(minkeylen) + " characters long, at " + tag->getTagLocation());
450 const bool ignorecase = tag->getBool("ignorecase");
451 const std::string mode = tag->getString("mode");
452 const std::string prefix = tag->getString("prefix");
453 const std::string suffix = tag->getString("suffix", ".IP");
454 if (stdalgo::string::equalsci(mode, "half"))
456 unsigned int domainparts = tag->getUInt("domainparts", 3, 1, 10);
457 newcloaks.push_back(CloakInfo(MODE_HALF_CLOAK, key, prefix, suffix, ignorecase, domainparts));
459 else if (stdalgo::string::equalsci(mode, "full"))
460 newcloaks.push_back(CloakInfo(MODE_OPAQUE, key, prefix, suffix, ignorecase));
462 throw ModuleException(mode + " is an invalid value for <cloak:mode>; acceptable values are 'half' and 'full', at " + tag->getTagLocation());
465 // The cloak configuration was valid so we can apply it.
466 cloaks.swap(newcloaks);
469 std::string GenCloak(const CloakInfo& info, const irc::sockets::sockaddrs& ip, const std::string& ipstr, const std::string& host)
473 irc::sockets::sockaddrs hostip;
474 bool host_is_ip = irc::sockets::aptosa(host, ip.port(), hostip) && hostip == ip;
478 case MODE_HALF_CLOAK:
481 chost = info.prefix + SegmentCloak(info, host, 1, 6) + VisibleDomainParts(host, info.domainparts);
482 if (chost.empty() || chost.length() > 50)
483 chost = SegmentIP(info, ip, false);
488 chost = SegmentIP(info, ip, true);
493 void OnSetUserIP(LocalUser* user) CXX11_OVERRIDE
495 // Connecting users are handled in OnUserConnect not here.
496 if (user->registered != REG_ALL || user->quitting)
499 // Remove the cloaks and generate new ones.
503 // If a user is using a cloak then update it.
504 if (user->IsModeSet(cu))
506 CloakList* cloaklist = cu.ext.get(user);
507 user->ChangeDisplayedHost(cloaklist->front());
511 void OnUserConnect(LocalUser* dest) CXX11_OVERRIDE
513 if (cu.ext.get(dest))
516 // TODO: decide how we are going to cloak AF_UNIX hostnames.
517 if (dest->client_sa.family() != AF_INET && dest->client_sa.family() != AF_INET6)
521 for (std::vector<CloakInfo>::const_iterator iter = cloaks.begin(); iter != cloaks.end(); ++iter)
522 cloaklist.push_back(GenCloak(*iter, dest->client_sa, dest->GetIPString(), dest->GetRealHost()));
523 cu.ext.set(dest, cloaklist);
527 CmdResult CommandCloak::Handle(User* user, const Params& parameters)
529 ModuleCloaking* mod = (ModuleCloaking*)(Module*)creator;
531 // If we're cloaking an IP address we pass it in the IP field too.
532 irc::sockets::sockaddrs sa;
533 const char* ipaddr = irc::sockets::aptosa(parameters[0], 0, sa) ? parameters[0].c_str() : "";
536 for (std::vector<CloakInfo>::const_iterator iter = mod->cloaks.begin(); iter != mod->cloaks.end(); ++iter)
538 const std::string cloak = mod->GenCloak(*iter, sa, ipaddr, parameters[0]);
539 user->WriteNotice(InspIRCd::Format("*** Cloak #%u for %s is %s", ++id, parameters[0].c_str(), cloak.c_str()));
544 MODULE_INIT(ModuleCloaking)