2 * InspIRCd -- Internet Relay Chat Daemon
4 * Copyright (C) 2009-2010 Daniel De Graaf <danieldg@inspircd.org>
5 * Copyright (C) 2006-2008 Robin Burchell <robin+git@viroteck.net>
6 * Copyright (C) 2008 Pippijn van Steenhoven <pip88nl@gmail.com>
7 * Copyright (C) 2003-2008 Craig Edwards <craigedwards@brainbox.cc>
8 * Copyright (C) 2007 John Brooks <john.brooks@dereferenced.net>
9 * Copyright (C) 2007 Dennis Friis <peavey@inspircd.org>
10 * Copyright (C) 2006 Oliver Lupton <oliverlupton@gmail.com>
12 * This file is part of InspIRCd. InspIRCd is free software: you can
13 * redistribute it and/or modify it under the terms of the GNU General Public
14 * License as published by the Free Software Foundation, version 2.
16 * This program is distributed in the hope that it will be useful, but WITHOUT
17 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
18 * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
21 * You should have received a copy of the GNU General Public License
22 * along with this program. If not, see <http://www.gnu.org/licenses/>.
27 #include "modules/hash.h"
31 /** 2.0 cloak of "half" of the hostname plus the full IP hash */
34 /** 2.0 cloak of IP hash, split at 2 common CIDR range points */
38 // lowercase-only encoding similar to base64, used for hash output
39 static const char base32[] = "0123456789abcdefghijklmnopqrstuv";
41 // The minimum length of a cloak key.
42 static const size_t minkeylen = 30;
46 // The method used for cloaking users.
49 // The number of parts of the hostname shown when using half cloaking.
50 unsigned int domainparts;
52 // The secret used for generating cloaks.
55 // The prefix for cloaks (e.g. MyNet-).
58 // The suffix for IP cloaks (e.g. .IP).
61 CloakInfo(CloakMode Mode, const std::string& Key, const std::string& Prefix, const std::string& Suffix, unsigned int DomainParts = 0)
63 , domainparts(DomainParts)
71 typedef std::vector<std::string> CloakList;
73 /** Handles user mode +x
75 class CloakUser : public ModeHandler
79 SimpleExtItem<CloakList> ext;
80 std::string debounce_uid;
84 CloakUser(Module* source)
85 : ModeHandler(source, "cloak", 'x', PARAM_NONE, MODETYPE_USER)
87 , ext("cloaked_host", ExtensionItem::EXT_USER, source)
93 ModeAction OnModeChange(User* source, User* dest, Channel* channel, std::string& parameter, bool adding) CXX11_OVERRIDE
95 LocalUser* user = IS_LOCAL(dest);
97 /* For remote clients, we don't take any action, we just allow it.
98 * The local server where they are will set their cloak instead.
99 * This is fine, as we will receive it later.
103 // Remote setters broadcast mode before host while local setters do the opposite, so this takes that into account
104 active = IS_LOCAL(source) ? adding : !adding;
105 dest->SetMode(this, adding);
106 return MODEACTION_ALLOW;
109 if (user->uuid == debounce_uid && debounce_ts == ServerInstance->Time())
111 // prevent spamming using /mode user +x-x+x-x+x-x
112 if (++debounce_count > 2)
113 return MODEACTION_DENY;
117 debounce_uid = user->uuid;
119 debounce_ts = ServerInstance->Time();
122 if (adding == user->IsModeSet(this))
123 return MODEACTION_DENY;
125 /* don't allow this user to spam modechanges */
127 user->CommandFloodPenalty += 5000;
131 // assume this is more correct
132 if (user->registered != REG_ALL && user->GetRealHost() != user->GetDisplayedHost())
133 return MODEACTION_DENY;
135 CloakList* cloaks = ext.get(user);
138 /* Force creation of missing cloak */
139 creator->OnUserConnect(user);
140 cloaks = ext.get(user);
143 // If we have a cloak then set the hostname.
144 if (cloaks && !cloaks->empty())
146 user->ChangeDisplayedHost(cloaks->front());
147 user->SetMode(this, true);
148 return MODEACTION_ALLOW;
151 return MODEACTION_DENY;
155 /* User is removing the mode, so restore their real host
156 * and make it match the displayed one.
158 user->SetMode(this, false);
159 user->ChangeDisplayedHost(user->GetRealHost().c_str());
160 return MODEACTION_ALLOW;
165 class CommandCloak : public Command
168 CommandCloak(Module* Creator) : Command(Creator, "CLOAK", 1)
174 CmdResult Handle(User* user, const Params& parameters) CXX11_OVERRIDE;
177 class ModuleCloaking : public Module
182 std::vector<CloakInfo> cloaks;
183 dynamic_reference<HashProvider> Hash;
188 , Hash(this, "hash/md5")
192 /** Takes a domain name and retrieves the subdomain which should be visible.
193 * This is usually the last \p domainparts labels but if not enough are
194 * present then all but the most specific label are used. If the domain name
195 * consists of one label only then none are used.
197 * Here are some examples for how domain names will be shortened assuming
198 * \p domainparts is set to the default of 3.
200 * "this.is.an.example.com" => ".an.example.com"
201 * "an.example.com" => ".example.com"
202 * "example.com" => ".com"
205 * @param host The hostname to cloak.
206 * @param domainparts The number of domain labels that should be visible.
207 * @return The visible segment of the hostname.
209 std::string VisibleDomainParts(const std::string& host, unsigned int domainparts)
211 // The position at which we found the last dot.
212 std::string::const_reverse_iterator dotpos;
214 // The number of dots we have seen so far.
215 unsigned int seendots = 0;
217 for (std::string::const_reverse_iterator iter = host.rbegin(); iter != host.rend(); ++iter)
222 // We have found a dot!
226 // Do we have enough segments to stop?
227 if (seendots >= domainparts)
231 // We only returns a domain part if more than one label is
232 // present. See above for a full explanation.
235 return std::string(dotpos.base() - 1, host.end());
239 * 2.0-style cloaking function
240 * @param item The item to cloak (part of an IP or hostname)
241 * @param id A unique ID for this type of item (to make it unique if the item matches)
242 * @param len The length of the output. Maximum for MD5 is 16 characters.
244 std::string SegmentCloak(const CloakInfo& info, const std::string& item, char id, size_t len)
247 input.reserve(info.key.length() + 3 + item.length());
249 input.append(info.key);
250 input.append(1, '\0'); // null does not terminate a C++ string
253 std::string rv = Hash->GenerateRaw(input).substr(0,len);
254 for(size_t i = 0; i < len; i++)
256 // this discards 3 bits per byte. We have an
257 // overabundance of bits in the hash output, doesn't
258 // matter which ones we are discarding.
259 rv[i] = base32[rv[i] & 0x1F];
264 std::string SegmentIP(const CloakInfo& info, const irc::sockets::sockaddrs& ip, bool full)
267 size_t hop1, hop2, hop3;
270 if (ip.family() == AF_INET6)
272 bindata = std::string((const char*)ip.in6.sin6_addr.s6_addr, 16);
278 // pfx s1.s2.s3. (xxxx.xxxx or s4) sfx
280 rv.reserve(info.prefix.length() + 26 + info.suffix.length());
284 bindata = std::string((const char*)&ip.in4.sin_addr, 4);
289 // pfx s1.s2. (xxx.xxx or s3) sfx
290 rv.reserve(info.prefix.length() + 15 + info.suffix.length());
293 rv.append(info.prefix);
294 rv.append(SegmentCloak(info, bindata, 10, len1));
297 rv.append(SegmentCloak(info, bindata, 11, len2));
302 rv.append(SegmentCloak(info, bindata, 12, len2));
309 rv.append(SegmentCloak(info, bindata, 13, 6));
310 rv.append(info.suffix);
314 if (ip.family() == AF_INET6)
316 rv.append(InspIRCd::Format(".%02x%02x.%02x%02x%s",
317 ip.in6.sin6_addr.s6_addr[2], ip.in6.sin6_addr.s6_addr[3],
318 ip.in6.sin6_addr.s6_addr[0], ip.in6.sin6_addr.s6_addr[1], info.suffix.c_str()));
322 const unsigned char* ip4 = (const unsigned char*)&ip.in4.sin_addr;
323 rv.append(InspIRCd::Format(".%d.%d%s", ip4[1], ip4[0], info.suffix.c_str()));
329 ModResult OnCheckBan(User* user, Channel* chan, const std::string& mask) CXX11_OVERRIDE
331 LocalUser* lu = IS_LOCAL(user);
333 return MOD_RES_PASSTHRU;
335 // Force the creation of cloaks if not already set.
338 // If the user has no cloaks (i.e. UNIX socket) then we do nothing here.
339 CloakList* cloaklist = cu.ext.get(user);
340 if (!cloaklist || cloaklist->empty())
341 return MOD_RES_PASSTHRU;
343 // Check if they have a cloaked host but are not using it.
344 for (CloakList::const_iterator iter = cloaklist->begin(); iter != cloaklist->end(); ++iter)
346 const std::string& cloak = *iter;
347 if (cloak != user->GetDisplayedHost())
349 const std::string cloakMask = user->nick + "!" + user->ident + "@" + cloak;
350 if (InspIRCd::Match(cloakMask, mask))
354 return MOD_RES_PASSTHRU;
357 void Prioritize() CXX11_OVERRIDE
359 /* Needs to be after m_banexception etc. */
360 ServerInstance->Modules->SetPriority(this, I_OnCheckBan, PRIORITY_LAST);
363 // this unsets umode +x on every host change. If we are actually doing a +x
364 // mode change, we will call SetMode back to true AFTER the host change is done.
365 void OnChangeHost(User* u, const std::string& host) CXX11_OVERRIDE
367 if (u->IsModeSet(cu) && !cu.active)
369 u->SetMode(cu, false);
373 Modes::ChangeList modechangelist;
374 modechangelist.push_remove(&cu);
375 ClientProtocol::Events::Mode modeevent(ServerInstance->FakeClient, NULL, u, modechangelist);
376 static_cast<LocalUser*>(u)->Send(modeevent);
381 Version GetVersion() CXX11_OVERRIDE
383 std::string testcloak = "broken";
384 if (Hash && !cloaks.empty())
386 const CloakInfo& info = cloaks.front();
389 case MODE_HALF_CLOAK:
390 // Use old cloaking verification to stay compatible with 2.0
391 // But verify domainparts when use 3.0-only features
392 if (info.domainparts == 3)
393 testcloak = info.prefix + SegmentCloak(info, "*", 3, 8) + info.suffix;
396 irc::sockets::sockaddrs sa;
397 testcloak = GenCloak(info, sa, "", testcloak + ConvToStr(info.domainparts));
401 testcloak = info.prefix + SegmentCloak(info, "*", 4, 8) + info.suffix;
404 return Version("Provides masking of user hostnames", VF_COMMON|VF_VENDOR, testcloak);
407 void ReadConfig(ConfigStatus& status) CXX11_OVERRIDE
409 ConfigTagList tags = ServerInstance->Config->ConfTags("cloak");
410 if (tags.first == tags.second)
411 throw ModuleException("You have loaded the cloaking module but not configured any <cloak> tags!");
413 std::vector<CloakInfo> newcloaks;
414 for (ConfigIter i = tags.first; i != tags.second; ++i)
416 ConfigTag* tag = i->second;
418 // Ensure that we have the <cloak:key> parameter.
419 const std::string key = tag->getString("key");
421 throw ModuleException("You have not defined a cloaking key. Define <cloak:key> as a " + ConvToStr(minkeylen) + "+ character network-wide secret, at " + tag->getTagLocation());
423 // If we are the first cloak method then mandate a strong key.
424 if (i == tags.first && key.length() < minkeylen)
425 throw ModuleException("Your cloaking key is not secure. It should be at least " + ConvToStr(minkeylen) + " characters long, at " + tag->getTagLocation());
427 const std::string mode = tag->getString("mode");
428 const std::string prefix = tag->getString("prefix");
429 const std::string suffix = tag->getString("suffix", ".IP");
430 if (stdalgo::string::equalsci(mode, "half"))
432 unsigned int domainparts = tag->getUInt("domainparts", 3, 1, 10);
433 newcloaks.push_back(CloakInfo(MODE_HALF_CLOAK, key, prefix, suffix, domainparts));
435 else if (stdalgo::string::equalsci(mode, "full"))
436 newcloaks.push_back(CloakInfo(MODE_OPAQUE, key, prefix, suffix));
438 throw ModuleException(mode + " is an invalid value for <cloak:mode>; acceptable values are 'half' and 'full', at " + tag->getTagLocation());
441 // The cloak configuration was valid so we can apply it.
442 cloaks.swap(newcloaks);
445 std::string GenCloak(const CloakInfo& info, const irc::sockets::sockaddrs& ip, const std::string& ipstr, const std::string& host)
449 irc::sockets::sockaddrs hostip;
450 bool host_is_ip = irc::sockets::aptosa(host, ip.port(), hostip) && hostip == ip;
454 case MODE_HALF_CLOAK:
457 chost = info.prefix + SegmentCloak(info, host, 1, 6) + VisibleDomainParts(host, info.domainparts);
458 if (chost.empty() || chost.length() > 50)
459 chost = SegmentIP(info, ip, false);
464 chost = SegmentIP(info, ip, true);
469 void OnSetUserIP(LocalUser* user) CXX11_OVERRIDE
471 // Connecting users are handled in OnUserConnect not here.
472 if (user->registered != REG_ALL)
475 // Remove the cloaks and generate new ones.
479 // If a user is using a cloak then update it.
480 if (user->IsModeSet(cu))
482 CloakList* cloaklist = cu.ext.get(user);
483 user->ChangeDisplayedHost(cloaklist->front());
487 void OnUserConnect(LocalUser* dest) CXX11_OVERRIDE
489 if (cu.ext.get(dest))
492 // TODO: decide how we are going to cloak AF_UNIX hostnames.
493 if (dest->client_sa.family() != AF_INET && dest->client_sa.family() != AF_INET6)
497 for (std::vector<CloakInfo>::const_iterator iter = cloaks.begin(); iter != cloaks.end(); ++iter)
498 cloaklist.push_back(GenCloak(*iter, dest->client_sa, dest->GetIPString(), dest->GetRealHost()));
499 cu.ext.set(dest, cloaklist);
503 CmdResult CommandCloak::Handle(User* user, const Params& parameters)
505 ModuleCloaking* mod = (ModuleCloaking*)(Module*)creator;
507 // If we're cloaking an IP address we pass it in the IP field too.
508 irc::sockets::sockaddrs sa;
509 const char* ipaddr = irc::sockets::aptosa(parameters[0], 0, sa) ? parameters[0].c_str() : "";
512 for (std::vector<CloakInfo>::const_iterator iter = mod->cloaks.begin(); iter != mod->cloaks.end(); ++iter)
514 const std::string cloak = mod->GenCloak(*iter, sa, ipaddr, parameters[0]);
515 user->WriteNotice(InspIRCd::Format("*** Cloak #%u for %s is %s", ++id, parameters[0].c_str(), cloak.c_str()));
520 MODULE_INIT(ModuleCloaking)