X-Git-Url: https://git.netwichtig.de/gitweb/?a=blobdiff_plain;f=src%2Fmodules%2Fm_cloaking.cpp;h=0aee306a341f798f66900c180839ce940d038f34;hb=e80a1296a096ff2c495b3cd2a3913d5e5f6ec450;hp=dfa5ee4e8b45603afa3041111ec178cf9ab17832;hpb=f2acdbc3820f0f4f5ef76a0a64e73d2a320df91f;p=user%2Fhenk%2Fcode%2Finspircd.git diff --git a/src/modules/m_cloaking.cpp b/src/modules/m_cloaking.cpp index dfa5ee4e8..0aee306a3 100644 --- a/src/modules/m_cloaking.cpp +++ b/src/modules/m_cloaking.cpp @@ -2,86 +2,62 @@ * | Inspire Internet Relay Chat Daemon | * +------------------------------------+ * - * InspIRCd: (C) 2002-2007 InspIRCd Development Team - * See: http://www.inspircd.org/wiki/index.php/Credits + * InspIRCd: (C) 2002-2009 InspIRCd Development Team + * See: http://wiki.inspircd.org/Credits * * This program is free but copyrighted software; see - * the file COPYING for details. + * 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"}; +enum CloakMode +{ + /** 1.2-compatible host-based cloak */ + MODE_COMPAT_HOST, + /** 1.2-compatible IP-only cloak */ + MODE_COMPAT_IPONLY, + /** 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 { - - 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) + LocalStringExt ext; + + CloakUser(Module* source) + : ModeHandler(source, "cloak", 'x', PARAM_NONE, MODETYPE_USER), + ext("cloaked_host", source) { } - ModeAction OnModeChange(userrec* source, userrec* dest, chanrec* channel, std::string ¶meter, bool adding) + ModeAction OnModeChange(User* source, User* dest, Channel* channel, std::string ¶meter, bool adding) { - if (source != dest) - return MODEACTION_DENY; - - /* For remote clients, we dont take any action, we just allow it. + /* 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 (!IS_LOCAL(dest)) + { + dest->SetMode('x',adding); return MODEACTION_ALLOW; + } + + /* don't allow this user to spam modechanges */ + dest->IncreasePenalty(5); if (adding) { @@ -96,71 +72,30 @@ class CloakUser : public ModeHandler * 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; + std::string* cloak = ext.get(dest); - /* 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()); + if (!cloak) + { + /* Force creation of missing cloak */ + creator->OnUserConnect(dest); + cloak = ext.get(dest); + } + if (cloak) + { + dest->ChangeDisplayedHost(cloak->c_str()); + dest->SetMode('x',true); + return MODEACTION_ALLOW; } - - 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. + /* User is removing the mode, so just restore their real host + * and make it match the displayed one. */ - dest->ChangeDisplayedHost(dest->host); + dest->ChangeDisplayedHost(dest->host.c_str()); dest->SetMode('x',false); return MODEACTION_ALLOW; } @@ -169,17 +104,83 @@ class CloakUser : public ModeHandler return MODEACTION_DENY; } - std::string Cloak4(const char* ip) +}; + + +class ModuleCloaking : public Module +{ + private: + CloakUser cu; + CloakMode mode; + std::string prefix; + std::string key; + unsigned int compatkey[4]; + const char* xtab[4]; + Module* HashProvider; + + public: + ModuleCloaking() : cu(this) + { + /* Attempt to locate the md5 service provider, bail if we can't find it */ + HashProvider = ServerInstance->Modules->Find("m_md5.so"); + if (!HashProvider) + throw ModuleException("Can't find m_md5.so. Please load m_md5.so before m_cloaking.so."); + + OnRehash(NULL); + + /* Register it with the core */ + if (!ServerInstance->Modes->AddMode(&cu)) + throw ModuleException("Could not add new modes!"); + + ServerInstance->Modules->UseInterface("HashRequest"); + ServerInstance->Extensions.Register(&cu.ext); + + Implementation eventlist[] = { I_OnRehash, I_OnCheckBan, I_OnUserConnect }; + ServerInstance->Modules->Attach(eventlist, this, 3); + + CloakExistingUsers(); + } + + /** 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); + } + + std::string CompatCloak4(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(); + seps.GetToken(octet[j]); i[j] = atoi(octet[j].c_str()); } @@ -188,128 +189,298 @@ class CloakUser : public ModeHandler octet[1] = octet[0] + "." + octet[1]; /* Reset the Hash module and send it our IV */ - HashResetRequest(Sender, HashProvider).Send(); - HashKeyRequest(Sender, HashProvider, iv).Send(); + + std::string rv; /* 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); + HashRequestIV hash(this, HashProvider, compatkey, xtab[(compatkey[k]+i[k]) % 4], octet[k]); + rv.append(hash.result.substr(0,6)); + if (k < 3) + rv.append("."); } /* Stick them all together */ - return std::string().append(ra[0]).append(".").append(ra[1]).append(".").append(ra[2]).append(".").append(ra[3]); + return rv; } - std::string Cloak6(const char* ip) + std::string CompatCloak6(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)); + HashRequestIV hash(this, HashProvider, compatkey, xtab[(compatkey[1]+rounds) % 4], item); + hashies.push_back(hash.result.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(); + HashRequestIV hash(this, HashProvider, compatkey, xtab[(compatkey[1]+rounds) % 4], item); + hashies.push_back(hash.result.substr(0,8)); } /* 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!"); + std::string ReversePartialIP(const irc::sockets::sockaddrs& ip) + { + char rv[50]; + if (ip.sa.sa_family == AF_INET6) + { + snprintf(rv, 50, ".%02x%02x.%02x%02x.%02x%02x.IP", + ip.in6.sin6_addr.s6_addr[4], ip.in6.sin6_addr.s6_addr[5], + 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]); + } + else + { + const unsigned char* ip4 = (const unsigned char*)&ip.in4.sin_addr; + snprintf(rv, 50, ".%d.%d.IP", ip4[1], ip4[0]); + } + return rv; } -}; + std::string SegmentIP(const irc::sockets::sockaddrs& ip) + { + std::string bindata; + int hop1, hop2; + if (ip.sa.sa_family == AF_INET6) + { + bindata = std::string((const char*)ip.in6.sin6_addr.s6_addr, 16); + hop1 = 8; + hop2 = 6; + } + else + { + bindata = std::string((const char*)&ip.in4.sin_addr, 4); + hop1 = 3; + hop2 = 2; + } -class ModuleCloaking : public Module -{ - private: - - CloakUser* cu; - Module* HashModule; + std::string rv; + rv.reserve(prefix.length() + 30); + rv.append(prefix); + rv.append(SegmentCloak(bindata, 2)); + rv.append(1, '.'); + bindata.erase(hop1); + rv.append(SegmentCloak(bindata, 3)); + rv.append(1, '.'); + bindata.erase(hop2); + rv.append(SegmentCloak(bindata, 4)); + rv.append(".IP"); + return rv; + } - public: - ModuleCloaking(InspIRCd* Me) - : Module(Me) + std::string SegmentCloak(const std::string& item, char id) { - 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."); + 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); + + HashRequest hash(this, HashProvider, input); + std::string rv = hash.binresult.substr(0,6); + for(int i=0; i < 6; 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; + } - /* Create new mode handler object */ - cu = new CloakUser(ServerInstance, this, HashModule); + void CloakExistingUsers() + { + std::string* cloak; + for (std::vector::iterator u = ServerInstance->Users->local_users.begin(); u != ServerInstance->Users->local_users.end(); u++) + { + cloak = cu.ext.get(*u); + if (!cloak) + { + OnUserConnect(*u); + } + } + } - /* Register it with the core */ - if (!ServerInstance->AddMode(cu, 'x')) - throw ModuleException("Could not add new modes!"); + ModResult OnCheckBan(User* user, Channel* chan, const std::string& mask) + { + char cmask[MAXBUF]; + std::string* cloak = cu.ext.get(user); + /* Check if they have a cloaked host, but are not using it */ + if (cloak && *cloak != user->dhost) + { + snprintf(cmask, MAXBUF, "%s!%s@%s", user->nick.c_str(), user->ident.c_str(), cloak->c_str()); + if (InspIRCd::Match(cmask,mask)) + return MOD_RES_DENY; + } + return MOD_RES_PASSTHRU; + } - OnRehash(NULL,""); + void Prioritize() + { + /* Needs to be after m_banexception etc. */ + ServerInstance->Modules->SetPriority(this, I_OnCheckBan, PRIORITY_LAST); } - - virtual ~ModuleCloaking() + + ~ModuleCloaking() { - ServerInstance->Modes->DelMode(cu); - DELETE(cu); - ServerInstance->DoneWithInterface("HashRequest"); + ServerInstance->Modules->DoneWithInterface("HashRequest"); } - - virtual Version GetVersion() + + 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); + return Version("Provides masking of user hostnames", VF_COMMON|VF_VENDOR,API_VERSION); } - virtual void OnRehash(userrec* user, const std::string ¶meter) + void OnRehash(User* user) { - cu->DoRehash(); + ConfigReader Conf; + prefix = Conf.ReadValue("cloak","prefix",0); + + std::string modestr = Conf.ReadValue("cloak", "mode", 0); + if (modestr == "compat-host") + mode = MODE_COMPAT_HOST; + else if (modestr == "compat-ip") + mode = MODE_COMPAT_IPONLY; + else if (modestr == "half") + mode = MODE_HALF_CLOAK; + else if (modestr == "full") + mode = MODE_OPAQUE; + else + throw ModuleException("Bad value for ; must be one of compat-host, compat-ip, half, full"); + + if (mode == MODE_COMPAT_HOST || mode == MODE_COMPAT_IPONLY) + { + bool lowercase = Conf.ReadFlag("cloak", "lowercase", 0); + + /* These are *not* using the need_positive parameter of ReadInteger - + * that will limit the valid values to only the positive values in a + * signed int. Instead, accept any value that fits into an int and + * cast it to an unsigned int. That will, a bit oddly, give us the full + * spectrum of an unsigned integer. - Special + * + * We must limit the keys or else we get different results on + * amd64/x86 boxes. - psychon */ + const unsigned int limit = 0x80000000; + compatkey[1] = (unsigned int) Conf.ReadInteger("cloak","key1",0,false); + compatkey[2] = (unsigned int) Conf.ReadInteger("cloak","key2",0,false); + compatkey[3] = (unsigned int) Conf.ReadInteger("cloak","key3",0,false); + compatkey[4] = (unsigned int) Conf.ReadInteger("cloak","key4",0,false); + + if (!lowercase) + { + xtab[0] = "F92E45D871BCA630"; + xtab[1] = "A1B9D80C72E653F4"; + xtab[2] = "1ABC078934DEF562"; + xtab[3] = "ABCDEF5678901234"; + } + else + { + xtab[0] = "f92e45d871bca630"; + xtab[1] = "a1b9d80c72e653f4"; + xtab[2] = "1abc078934def562"; + xtab[3] = "abcdef5678901234"; + } + + if (prefix.empty()) + prefix = ServerInstance->Config->Network; + + if (!compatkey[1] || !compatkey[2] || !compatkey[3] || !compatkey[4] || + compatkey[1] >= limit || compatkey[2] >= limit || compatkey[3] >= limit || compatkey[4] >= limit) + { + std::string detail; + if (!compatkey[1] || compatkey[1] >= limit) + detail = " is not valid, it may be set to a too high/low value, or it may not exist."; + else if (!compatkey[2] || compatkey[2] >= limit) + detail = " is not valid, it may be set to a too high/low value, or it may not exist."; + else if (!compatkey[3] || compatkey[3] >= limit) + detail = " is not valid, it may be set to a too high/low value, or it may not exist."; + else if (!compatkey[4] || compatkey[4] >= limit) + detail = " is not valid, it may be set to a too high/low value, or it may not exist."; + + throw ModuleException("You have not defined cloak keys for m_cloaking!!! THIS IS INSECURE AND SHOULD BE CHECKED! - " + detail); + } + } + else + { + key = Conf.ReadFlag("cloak", "key", 0); + if (key.empty() || key == "secret") + throw ModuleException("You have not defined cloak keys for m_cloaking. Define as a network-wide secret."); + } } - void Implements(char* List) + void OnUserConnect(User* dest) { - List[I_OnRehash] = 1; + std::string* cloak = cu.ext.get(dest); + if (cloak) + return; + + if (dest->host.find('.') == std::string::npos && dest->host.find(':') == std::string::npos) + return; + + std::string ipstr = dest->GetIPString(); + std::string chost; + + switch (mode) + { + case MODE_COMPAT_HOST: + { + if (ipstr != dest->host) + { + std::string tail = LastTwoDomainParts(dest->host); + + /** Reset the Hash module, and send it our IV and hex table */ + HashRequestIV hash(this, HashProvider, compatkey, xtab[(dest->host[0]) % 4], dest->host); + + /* Generate a cloak using specialized Hash */ + chost = prefix + "-" + hash.result.substr(0,8) + tail; + + /* Fix by brain - if the cloaked host is > the max length of a host (64 bytes + * according to the DNS RFC) then they get cloaked as an IP. + */ + if (chost.length() <= 64) + break; + } + // fall through to IP cloak + } + case MODE_COMPAT_IPONLY: + if (dest->client_sa.sa.sa_family == AF_INET6) + chost = CompatCloak6(ipstr.c_str()); + else + chost = CompatCloak4(ipstr.c_str()); + break; + case MODE_HALF_CLOAK: + { + std::string tail; + if (ipstr != dest->host) + tail = LastTwoDomainParts(dest->host); + if (tail.empty() || tail.length() > 50) + tail = ReversePartialIP(dest->client_sa); + chost = prefix + SegmentCloak(dest->host, 1) + tail; + break; + } + case MODE_OPAQUE: + default: + chost = prefix + SegmentIP(dest->client_sa); + } + cu.ext.set(dest,chost); } + }; MODULE_INIT(ModuleCloaking)