X-Git-Url: https://git.netwichtig.de/gitweb/?a=blobdiff_plain;ds=sidebyside;f=src%2Fmodules%2Fm_cloaking.cpp;h=c4cbbef211e6476ab6ed19cfd2f8fe30f2176fdb;hb=124c17e14134a4999afc1a5e981ab7c75b3694b9;hp=d7992301cfa26390af033eec29a1a417d6974291;hpb=bab14f0dd2345c9d7dcbc47c918563709e1ac094;p=user%2Fhenk%2Fcode%2Finspircd.git diff --git a/src/modules/m_cloaking.cpp b/src/modules/m_cloaking.cpp index d7992301c..515244231 100644 --- a/src/modules/m_cloaking.cpp +++ b/src/modules/m_cloaking.cpp @@ -1 +1,418 @@ -/* +------------------------------------+ * | Inspire Internet Relay Chat Daemon | * +------------------------------------+ * * InspIRCd: (C) 2002-2007 InspIRCd Development Team * See: http://www.inspircd.org/wiki/index.php/Credits * * This program is free but copyrighted software; see * the file COPYING for details. * * --------------------------------------------------- */ #include "inspircd.h" #include "users.h" #include "channels.h" #include "modules.h" #include "m_hash.h" /* $ModDesc: Provides masking of user hostnames */ /* $ModDep: m_hash.h */ /* Used to vary the output a little more depending on the cloak keys */ static const char* xtab[] = {"F92E45D871BCA630", "A1B9D80C72E653F4", "1ABC078934DEF562", "ABCDEF5678901234"}; /** Handles user mode +x */ class CloakUser : public ModeHandler { std::string prefix; unsigned int key1; unsigned int key2; unsigned int key3; unsigned int key4; Module* Sender; Module* HashProvider; /** This function takes a domain name string and returns just the last two domain parts, * or the last domain part if only two are available. Failing that it just returns what it was given. * * For example, if it is passed "svn.inspircd.org" it will return ".inspircd.org". * If it is passed "brainbox.winbot.co.uk" it will return ".co.uk", * and if it is passed "localhost.localdomain" it will return ".localdomain". * * This is used to ensure a significant part of the host is always cloaked (see Bug #216) */ std::string LastTwoDomainParts(const std::string &host) { int dots = 0; std::string::size_type splitdot = host.length(); for (std::string::size_type x = host.length() - 1; x; --x) { if (host[x] == '.') { splitdot = x; dots++; } if (dots >= 3) break; } if (splitdot == host.length()) return host; else return host.substr(splitdot); } public: CloakUser(InspIRCd* Instance, Module* Source, Module* Hash) : ModeHandler(Instance, 'x', 0, 0, false, MODETYPE_USER, false), Sender(Source), HashProvider(Hash) { } ModeAction OnModeChange(userrec* source, userrec* dest, chanrec* channel, std::string ¶meter, bool adding) { if (source != dest) return MODEACTION_DENY; /* For remote clients, we dont take any action, we just allow it. * The local server where they are will set their cloak instead. */ if (!IS_LOCAL(dest)) return MODEACTION_ALLOW; if (adding) { if(!dest->IsModeSet('x')) { /* The mode is being turned on - so attempt to * allocate the user a cloaked host using a non-reversible * algorithm (its simple, but its non-reversible so the * simplicity doesnt really matter). This algorithm * will not work if the user has only one level of domain * naming in their hostname (e.g. if they are on a lan or * are connecting via localhost) -- this doesnt matter much. */ char* n1 = strchr(dest->host,'.'); char* n2 = strchr(dest->host,':'); if (n1 || n2) { /* InspIRCd users have two hostnames; A displayed * hostname which can be modified by modules (e.g. * to create vhosts, implement chghost, etc) and a * 'real' hostname which you shouldnt write to. */ unsigned int iv[] = { key1, key2, key3, key4 }; std::string a = LastTwoDomainParts(dest->host); std::string b; /** Reset the Hash module, and send it our IV and hex table */ HashResetRequest(Sender, HashProvider).Send(); HashKeyRequest(Sender, HashProvider, iv).Send(); HashHexRequest(Sender, HashProvider, xtab[(*dest->host) % 4]); /* Generate a cloak using specialized Hash */ std::string hostcloak = prefix + "-" + std::string(HashSumRequest(Sender, HashProvider, dest->host).Send()).substr(0,8) + a; /* Fix by brain - if the cloaked host is > the max length of a host (64 bytes * according to the DNS RFC) then tough titty, they get cloaked as an IP. * Their ISP shouldnt go to town on subdomains, or they shouldnt have a kiddie * vhost. */ #ifdef IPV6 in6_addr testaddr; in_addr testaddr2; if ((dest->GetProtocolFamily() == AF_INET6) && (inet_pton(AF_INET6,dest->host,&testaddr) < 1) && (hostcloak.length() <= 64)) /* Invalid ipv6 address, and ipv6 user (resolved host) */ b = hostcloak; else if ((dest->GetProtocolFamily() == AF_INET) && (inet_aton(dest->host,&testaddr2) < 1) && (hostcloak.length() <= 64)) /* Invalid ipv4 address, and ipv4 user (resolved host) */ b = hostcloak; else /* Valid ipv6 or ipv4 address (not resolved) ipv4 or ipv6 user */ b = ((!strchr(dest->host,':')) ? Cloak4(dest->host) : Cloak6(dest->host)); #else in_addr testaddr; if ((inet_aton(dest->host,&testaddr) < 1) && (hostcloak.length() <= 64)) /* Invalid ipv4 address, and ipv4 user (resolved host) */ b = hostcloak; else /* Valid ipv4 address (not resolved) ipv4 user */ b = Cloak4(dest->host); #endif dest->ChangeDisplayedHost(b.c_str()); } dest->SetMode('x',true); return MODEACTION_ALLOW; } } else { if (dest->IsModeSet('x')) { /* User is removing the mode, so just restore their real host * and make it match the displayed one. */ dest->ChangeDisplayedHost(dest->host); dest->SetMode('x',false); return MODEACTION_ALLOW; } } return MODEACTION_DENY; } std::string Cloak4(const char* ip) { unsigned int iv[] = { key1, key2, key3, key4 }; irc::sepstream seps(ip, '.'); std::string ra[4];; std::string octet[4]; int i[4]; for (int j = 0; j < 4; j++) { octet[j] = seps.GetToken(); i[j] = atoi(octet[j].c_str()); } octet[3] = octet[0] + "." + octet[1] + "." + octet[2] + "." + octet[3]; octet[2] = octet[0] + "." + octet[1] + "." + octet[2]; octet[1] = octet[0] + "." + octet[1]; /* Reset the Hash module and send it our IV */ HashResetRequest(Sender, HashProvider).Send(); HashKeyRequest(Sender, HashProvider, iv).Send(); /* Send the Hash module a different hex table for each octet group's Hash sum */ for (int k = 0; k < 4; k++) { HashHexRequest(Sender, HashProvider, xtab[(iv[k]+i[k]) % 4]).Send(); ra[k] = std::string(HashSumRequest(Sender, HashProvider, octet[k]).Send()).substr(0,6); } /* Stick them all together */ return std::string().append(ra[0]).append(".").append(ra[1]).append(".").append(ra[2]).append(".").append(ra[3]); } std::string Cloak6(const char* ip) { /* Theyre using 4in6 (YUCK). Translate as ipv4 cloak */ if (!strncmp(ip, "0::ffff:", 8)) return Cloak4(ip + 8); /* If we get here, yes it really is an ipv6 ip */ unsigned int iv[] = { key1, key2, key3, key4 }; std::vector hashies; std::string item; int rounds = 0; /* Reset the Hash module and send it our IV */ HashResetRequest(Sender, HashProvider).Send(); HashKeyRequest(Sender, HashProvider, iv).Send(); for (const char* input = ip; *input; input++) { item += *input; if (item.length() > 7) { /* Send the Hash module a different hex table for each octet group's Hash sum */ HashHexRequest(Sender, HashProvider, xtab[(key1+rounds) % 4]).Send(); hashies.push_back(std::string(HashSumRequest(Sender, HashProvider, item).Send()).substr(0,8)); item.clear(); } rounds++; } if (!item.empty()) { /* Send the Hash module a different hex table for each octet group's Hash sum */ HashHexRequest(Sender, HashProvider, xtab[(key1+rounds) % 4]).Send(); hashies.push_back(std::string(HashSumRequest(Sender, HashProvider, item).Send()).substr(0,8)); item.clear(); } /* Stick them all together */ return irc::stringjoiner(":", hashies, 0, hashies.size() - 1).GetJoined(); } void DoRehash() { ConfigReader Conf(ServerInstance); key1 = key2 = key3 = key4 = 0; key1 = Conf.ReadInteger("cloak","key1",0,true); key2 = Conf.ReadInteger("cloak","key2",0,true); key3 = Conf.ReadInteger("cloak","key3",0,true); key4 = Conf.ReadInteger("cloak","key4",0,true); prefix = Conf.ReadValue("cloak","prefix",0); if (prefix.empty()) prefix = ServerInstance->Config->Network; if (!key1 && !key2 && !key3 && !key4) throw ModuleException("You have not defined cloak keys for m_cloaking!!! THIS IS INSECURE AND SHOULD BE CHECKED!"); } }; class ModuleCloaking : public Module { private: CloakUser* cu; Module* HashModule; public: ModuleCloaking(InspIRCd* Me) : Module(Me) { ServerInstance->UseInterface("HashRequest"); /* Attempt to locate the md5 service provider, bail if we can't find it */ HashModule = ServerInstance->FindModule("m_md5.so"); if (!HashModule) throw ModuleException("Can't find m_md5.so. Please load m_md5.so before m_cloaking.so."); /* Create new mode handler object */ cu = new CloakUser(ServerInstance, this, HashModule); /* Register it with the core */ if (!ServerInstance->AddMode(cu, 'x')) throw ModuleException("Could not add new modes!"); OnRehash(NULL,""); } virtual ~ModuleCloaking() { ServerInstance->Modes->DelMode(cu); DELETE(cu); ServerInstance->DoneWithInterface("HashRequest"); } virtual Version GetVersion() { // returns the version number of the module to be // listed in /MODULES return Version(1,1,0,2,VF_COMMON|VF_VENDOR,API_VERSION); } virtual void OnRehash(userrec* user, const std::string ¶meter) { cu->DoRehash(); } void Implements(char* List) { List[I_OnRehash] = 1; } }; MODULE_INIT(ModuleCloaking) \ No newline at end of file +/* + * InspIRCd -- Internet Relay Chat Daemon + * + * Copyright (C) 2009-2010 Daniel De Graaf + * Copyright (C) 2006-2008 Robin Burchell + * Copyright (C) 2008 Pippijn van Steenhoven + * Copyright (C) 2003-2008 Craig Edwards + * Copyright (C) 2007 John Brooks + * Copyright (C) 2007 Dennis Friis + * Copyright (C) 2006 Oliver Lupton + * + * This file is part of InspIRCd. InspIRCd is free software: you can + * redistribute it and/or modify it under the terms of the GNU General Public + * License as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS + * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more + * details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + */ + + +#include "inspircd.h" +#include "modules/hash.h" + +enum CloakMode +{ + /** 2.0 cloak of "half" of the hostname plus the full IP hash */ + MODE_HALF_CLOAK, + /** 2.0 cloak of IP hash, split at 2 common CIDR range points */ + MODE_OPAQUE +}; + +// lowercase-only encoding similar to base64, used for hash output +static const char base32[] = "0123456789abcdefghijklmnopqrstuv"; + +/** Handles user mode +x + */ +class CloakUser : public ModeHandler +{ + public: + bool active; + LocalStringExt ext; + std::string debounce_uid; + time_t debounce_ts; + int debounce_count; + + CloakUser(Module* source) + : ModeHandler(source, "cloak", 'x', PARAM_NONE, MODETYPE_USER) + , active(false) + , ext("cloaked_host", ExtensionItem::EXT_USER, source) + , debounce_ts(0) + , debounce_count(0) + { + } + + ModeAction OnModeChange(User* source, User* dest, Channel* channel, std::string& parameter, bool adding) CXX11_OVERRIDE + { + LocalUser* user = IS_LOCAL(dest); + + /* For remote clients, we don't take any action, we just allow it. + * The local server where they are will set their cloak instead. + * This is fine, as we will receive it later. + */ + if (!user) + { + // Remote setters broadcast mode before host while local setters do the opposite, so this takes that into account + active = IS_LOCAL(source) ? adding : !adding; + dest->SetMode(this, adding); + return MODEACTION_ALLOW; + } + + if (user->uuid == debounce_uid && debounce_ts == ServerInstance->Time()) + { + // prevent spamming using /mode user +x-x+x-x+x-x + if (++debounce_count > 2) + return MODEACTION_DENY; + } + else + { + debounce_uid = user->uuid; + debounce_count = 1; + debounce_ts = ServerInstance->Time(); + } + + if (adding == user->IsModeSet(this)) + return MODEACTION_DENY; + + /* don't allow this user to spam modechanges */ + if (source == dest) + user->CommandFloodPenalty += 5000; + + if (adding) + { + // assume this is more correct + if (user->registered != REG_ALL && user->GetRealHost() != user->GetDisplayedHost()) + return MODEACTION_DENY; + + std::string* cloak = ext.get(user); + + if (!cloak) + { + /* Force creation of missing cloak */ + creator->OnUserConnect(user); + cloak = ext.get(user); + } + if (cloak) + { + user->ChangeDisplayedHost(*cloak); + user->SetMode(this, true); + return MODEACTION_ALLOW; + } + else + return MODEACTION_DENY; + } + else + { + /* User is removing the mode, so restore their real host + * and make it match the displayed one. + */ + user->SetMode(this, false); + user->ChangeDisplayedHost(user->GetRealHost().c_str()); + return MODEACTION_ALLOW; + } + } +}; + +class CommandCloak : public Command +{ + public: + CommandCloak(Module* Creator) : Command(Creator, "CLOAK", 1) + { + flags_needed = 'o'; + syntax = ""; + } + + CmdResult Handle(const std::vector& parameters, User* user) CXX11_OVERRIDE; +}; + +class ModuleCloaking : public Module +{ + public: + CloakUser cu; + CloakMode mode; + CommandCloak ck; + std::string prefix; + std::string suffix; + std::string key; + unsigned int domainparts; + dynamic_reference Hash; + + ModuleCloaking() + : cu(this) + , mode(MODE_OPAQUE) + , ck(this) + , Hash(this, "hash/md5") + { + } + + /** This function takes a domain name string and returns just the last two domain parts, + * or the last domain part if only two are available. Failing that it just returns what it was given. + * + * For example, if it is passed "svn.inspircd.org" it will return ".inspircd.org". + * If it is passed "brainbox.winbot.co.uk" it will return ".co.uk", + * and if it is passed "localhost.localdomain" it will return ".localdomain". + * + * This is used to ensure a significant part of the host is always cloaked (see Bug #216) + */ + std::string LastTwoDomainParts(const std::string &host) + { + unsigned int dots = 0; + std::string::size_type splitdot = host.length(); + + for (std::string::size_type x = host.length() - 1; x; --x) + { + if (host[x] == '.') + { + splitdot = x; + dots++; + } + if (dots >= domainparts) + break; + } + + if (splitdot == host.length()) + return ""; + else + return host.substr(splitdot); + } + + /** + * 2.0-style cloaking function + * @param item The item to cloak (part of an IP or hostname) + * @param id A unique ID for this type of item (to make it unique if the item matches) + * @param len The length of the output. Maximum for MD5 is 16 characters. + */ + std::string SegmentCloak(const std::string& item, char id, size_t len) + { + std::string input; + input.reserve(key.length() + 3 + item.length()); + input.append(1, id); + input.append(key); + input.append(1, '\0'); // null does not terminate a C++ string + input.append(item); + + std::string rv = Hash->GenerateRaw(input).substr(0,len); + for(size_t i = 0; i < len; i++) + { + // this discards 3 bits per byte. We have an + // overabundance of bits in the hash output, doesn't + // matter which ones we are discarding. + rv[i] = base32[rv[i] & 0x1F]; + } + return rv; + } + + std::string SegmentIP(const irc::sockets::sockaddrs& ip, bool full) + { + std::string bindata; + size_t hop1, hop2, hop3; + size_t len1, len2; + std::string rv; + if (ip.sa.sa_family == AF_INET6) + { + bindata = std::string((const char*)ip.in6.sin6_addr.s6_addr, 16); + hop1 = 8; + hop2 = 6; + hop3 = 4; + len1 = 6; + len2 = 4; + // pfx s1.s2.s3. (xxxx.xxxx or s4) sfx + // 6 4 4 9/6 + rv.reserve(prefix.length() + 26 + suffix.length()); + } + else + { + bindata = std::string((const char*)&ip.in4.sin_addr, 4); + hop1 = 3; + hop2 = 0; + hop3 = 2; + len1 = len2 = 3; + // pfx s1.s2. (xxx.xxx or s3) sfx + rv.reserve(prefix.length() + 15 + suffix.length()); + } + + rv.append(prefix); + rv.append(SegmentCloak(bindata, 10, len1)); + rv.append(1, '.'); + bindata.erase(hop1); + rv.append(SegmentCloak(bindata, 11, len2)); + if (hop2) + { + rv.append(1, '.'); + bindata.erase(hop2); + rv.append(SegmentCloak(bindata, 12, len2)); + } + + if (full) + { + rv.append(1, '.'); + bindata.erase(hop3); + rv.append(SegmentCloak(bindata, 13, 6)); + rv.append(suffix); + } + else + { + if (ip.sa.sa_family == AF_INET6) + { + rv.append(InspIRCd::Format(".%02x%02x.%02x%02x%s", + ip.in6.sin6_addr.s6_addr[2], ip.in6.sin6_addr.s6_addr[3], + ip.in6.sin6_addr.s6_addr[0], ip.in6.sin6_addr.s6_addr[1], suffix.c_str())); + } + else + { + const unsigned char* ip4 = (const unsigned char*)&ip.in4.sin_addr; + rv.append(InspIRCd::Format(".%d.%d%s", ip4[1], ip4[0], suffix.c_str())); + } + } + return rv; + } + + ModResult OnCheckBan(User* user, Channel* chan, const std::string& mask) CXX11_OVERRIDE + { + LocalUser* lu = IS_LOCAL(user); + if (!lu) + return MOD_RES_PASSTHRU; + + OnUserConnect(lu); + std::string* cloak = cu.ext.get(user); + /* Check if they have a cloaked host, but are not using it */ + if (cloak && *cloak != user->GetDisplayedHost()) + { + const std::string cloakMask = user->nick + "!" + user->ident + "@" + *cloak; + if (InspIRCd::Match(cloakMask, mask)) + return MOD_RES_DENY; + } + return MOD_RES_PASSTHRU; + } + + void Prioritize() CXX11_OVERRIDE + { + /* Needs to be after m_banexception etc. */ + ServerInstance->Modules->SetPriority(this, I_OnCheckBan, PRIORITY_LAST); + } + + // this unsets umode +x on every host change. If we are actually doing a +x + // mode change, we will call SetMode back to true AFTER the host change is done. + void OnChangeHost(User* u, const std::string& host) CXX11_OVERRIDE + { + if (u->IsModeSet(cu) && !cu.active) + { + u->SetMode(cu, false); + u->WriteCommand("MODE", "-" + ConvToStr(cu.GetModeChar())); + } + cu.active = false; + } + + Version GetVersion() CXX11_OVERRIDE + { + std::string testcloak = "broken"; + if (Hash) + { + switch (mode) + { + case MODE_HALF_CLOAK: + // Use old cloaking verification to stay compatible with 2.0 + // But verify domainparts when use 3.0-only features + if (domainparts == 3) + testcloak = prefix + SegmentCloak("*", 3, 8) + suffix; + else + { + irc::sockets::sockaddrs sa; + testcloak = GenCloak(sa, "", testcloak + ConvToStr(domainparts)); + } + break; + case MODE_OPAQUE: + testcloak = prefix + SegmentCloak("*", 4, 8) + suffix; + } + } + return Version("Provides masking of user hostnames", VF_COMMON|VF_VENDOR, testcloak); + } + + void ReadConfig(ConfigStatus& status) CXX11_OVERRIDE + { + ConfigTag* tag = ServerInstance->Config->ConfValue("cloak"); + prefix = tag->getString("prefix"); + suffix = tag->getString("suffix", ".IP"); + + std::string modestr = tag->getString("mode"); + if (modestr == "half") + { + mode = MODE_HALF_CLOAK; + domainparts = tag->getUInt("domainparts", 3, 1, 10); + } + else if (modestr == "full") + mode = MODE_OPAQUE; + else + throw ModuleException("Bad value for ; must be half or full"); + + key = tag->getString("key"); + if (key.empty() || key == "secret") + throw ModuleException("You have not defined cloak keys for m_cloaking. Define as a network-wide secret."); + } + + std::string GenCloak(const irc::sockets::sockaddrs& ip, const std::string& ipstr, const std::string& host) + { + std::string chost; + + irc::sockets::sockaddrs hostip; + bool host_is_ip = irc::sockets::aptosa(host, ip.port(), hostip) && hostip == ip; + + switch (mode) + { + case MODE_HALF_CLOAK: + { + if (!host_is_ip) + chost = prefix + SegmentCloak(host, 1, 6) + LastTwoDomainParts(host); + if (chost.empty() || chost.length() > 50) + chost = SegmentIP(ip, false); + break; + } + case MODE_OPAQUE: + default: + chost = SegmentIP(ip, true); + } + return chost; + } + + void OnUserConnect(LocalUser* dest) CXX11_OVERRIDE + { + std::string* cloak = cu.ext.get(dest); + if (cloak) + return; + + cu.ext.set(dest, GenCloak(dest->client_sa, dest->GetIPString(), dest->GetRealHost())); + } +}; + +CmdResult CommandCloak::Handle(const std::vector ¶meters, User *user) +{ + ModuleCloaking* mod = (ModuleCloaking*)(Module*)creator; + irc::sockets::sockaddrs sa; + std::string cloak; + + if (irc::sockets::aptosa(parameters[0], 0, sa)) + cloak = mod->GenCloak(sa, parameters[0], parameters[0]); + else + cloak = mod->GenCloak(sa, "", parameters[0]); + + user->WriteNotice("*** Cloak for " + parameters[0] + " is " + cloak); + + return CMD_SUCCESS; +} + +MODULE_INIT(ModuleCloaking)