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) 2007 Craig Edwards <craigedwards@brainbox.cc>
7 * Copyright (C) 2006-2007 Dennis Friis <peavey@inspircd.org>
8 * Copyright (C) 2007 John Brooks <john.brooks@dereferenced.net>
10 * This file is part of InspIRCd. InspIRCd is free software: you can
11 * redistribute it and/or modify it under the terms of the GNU General Public
12 * License as published by the Free Software Foundation, version 2.
14 * This program is distributed in the hope that it will be useful, but WITHOUT
15 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
16 * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
19 * You should have received a copy of the GNU General Public License
20 * along with this program. If not, see <http://www.gnu.org/licenses/>.
26 #include "modules/dns.h"
27 #include "modules/stats.h"
29 /* Class holding data for a single entry */
30 class DNSBLConfEntry : public refcountbase
33 enum EnumBanaction { I_UNKNOWN, I_KILL, I_ZLINE, I_KLINE, I_GLINE, I_MARK };
34 enum EnumType { A_RECORD, A_BITMASK };
35 std::string name, ident, host, domain, reason;
36 EnumBanaction banaction;
38 unsigned long duration;
40 unsigned char records[256];
41 unsigned long stats_hits, stats_misses;
42 DNSBLConfEntry(): type(A_BITMASK),duration(86400),bitmask(0),stats_hits(0), stats_misses(0) {}
46 /** Resolver for CGI:IRC hostnames encoded in ident/real name
48 class DNSBLResolver : public DNS::Request
51 irc::sockets::sockaddrs theirsa;
53 LocalStringExt& nameExt;
54 LocalIntExt& countExt;
55 reference<DNSBLConfEntry> ConfEntry;
58 DNSBLResolver(DNS::Manager *mgr, Module *me, LocalStringExt& match, LocalIntExt& ctr, const std::string &hostname, LocalUser* u, reference<DNSBLConfEntry> conf)
59 : DNS::Request(mgr, me, hostname, DNS::QUERY_A, true)
60 , theirsa(u->client_sa)
68 /* Note: This may be called multiple times for multiple A record results */
69 void OnLookupComplete(const DNS::Query *r) CXX11_OVERRIDE
71 /* Check the user still exists */
72 LocalUser* them = IS_LOCAL(ServerInstance->FindUUID(theiruid));
73 if (!them || them->client_sa != theirsa)
76 const DNS::ResourceRecord* const ans_record = r->FindAnswerOfType(DNS::QUERY_A);
80 // All replies should be in 127.0.0.0/8
81 if (ans_record->rdata.compare(0, 4, "127.") != 0)
83 ServerInstance->SNO->WriteGlobalSno('d', "DNSBL: %s returned address outside of acceptable subnet 127.0.0.0/8: %s", ConfEntry->domain.c_str(), ans_record->rdata.c_str());
84 ConfEntry->stats_misses++;
88 int i = countExt.get(them);
90 countExt.set(them, i - 1);
92 // Now we calculate the bitmask: 256*(256*(256*a+b)+c)+d
94 unsigned int bitmask = 0, record = 0;
98 inet_pton(AF_INET, ans_record->rdata.c_str(), &resultip);
100 switch (ConfEntry->type)
102 case DNSBLConfEntry::A_BITMASK:
103 bitmask = resultip.s_addr >> 24; /* Last octet (network byte order) */
104 bitmask &= ConfEntry->bitmask;
105 match = (bitmask != 0);
107 case DNSBLConfEntry::A_RECORD:
108 record = resultip.s_addr >> 24; /* Last octet */
109 match = (ConfEntry->records[record] == 1);
115 std::string reason = ConfEntry->reason;
116 std::string::size_type x = reason.find("%ip%");
117 while (x != std::string::npos)
120 reason.insert(x, them->GetIPString());
121 x = reason.find("%ip%");
124 ConfEntry->stats_hits++;
126 switch (ConfEntry->banaction)
128 case DNSBLConfEntry::I_KILL:
130 ServerInstance->Users->QuitUser(them, "Killed (" + reason + ")");
133 case DNSBLConfEntry::I_MARK:
135 if (!ConfEntry->ident.empty())
137 them->WriteNotice("Your ident has been set to " + ConfEntry->ident + " because you matched " + reason);
138 them->ChangeIdent(ConfEntry->ident);
141 if (!ConfEntry->host.empty())
143 them->WriteNotice("Your host has been set to " + ConfEntry->host + " because you matched " + reason);
144 them->ChangeDisplayedHost(ConfEntry->host);
147 nameExt.set(them, ConfEntry->name);
150 case DNSBLConfEntry::I_KLINE:
152 KLine* kl = new KLine(ServerInstance->Time(), ConfEntry->duration, ServerInstance->Config->ServerName.c_str(), reason.c_str(),
153 "*", them->GetIPString());
154 if (ServerInstance->XLines->AddLine(kl,NULL))
156 ServerInstance->SNO->WriteGlobalSno('x', "K-line added due to DNSBL match on *@%s to expire in %s (on %s): %s",
157 them->GetIPString().c_str(), InspIRCd::DurationString(kl->duration).c_str(),
158 InspIRCd::TimeString(kl->expiry).c_str(), reason.c_str());
159 ServerInstance->XLines->ApplyLines();
168 case DNSBLConfEntry::I_GLINE:
170 GLine* gl = new GLine(ServerInstance->Time(), ConfEntry->duration, ServerInstance->Config->ServerName.c_str(), reason.c_str(),
171 "*", them->GetIPString());
172 if (ServerInstance->XLines->AddLine(gl,NULL))
174 ServerInstance->SNO->WriteGlobalSno('x', "G-line added due to DNSBL match on *@%s to expire in %s (on %s): %s",
175 them->GetIPString().c_str(), InspIRCd::DurationString(gl->duration).c_str(),
176 InspIRCd::TimeString(gl->expiry).c_str(), reason.c_str());
177 ServerInstance->XLines->ApplyLines();
186 case DNSBLConfEntry::I_ZLINE:
188 ZLine* zl = new ZLine(ServerInstance->Time(), ConfEntry->duration, ServerInstance->Config->ServerName.c_str(), reason.c_str(),
189 them->GetIPString());
190 if (ServerInstance->XLines->AddLine(zl,NULL))
192 ServerInstance->SNO->WriteGlobalSno('x', "Z-line added due to DNSBL match on %s to expire in %s (on %s): %s",
193 them->GetIPString().c_str(), InspIRCd::DurationString(zl->duration).c_str(),
194 InspIRCd::TimeString(zl->expiry).c_str(), reason.c_str());
195 ServerInstance->XLines->ApplyLines();
204 case DNSBLConfEntry::I_UNKNOWN:
209 ServerInstance->SNO->WriteGlobalSno('d', "Connecting user %s (%s) detected as being on the '%s' DNS blacklist with result %d",
210 them->GetFullRealHost().c_str(), them->GetIPString().c_str(), ConfEntry->name.c_str(), (ConfEntry->type==DNSBLConfEntry::A_BITMASK) ? bitmask : record);
213 ConfEntry->stats_misses++;
216 void OnError(const DNS::Query *q) CXX11_OVERRIDE
218 LocalUser* them = IS_LOCAL(ServerInstance->FindUUID(theiruid));
219 if (!them || them->client_sa != theirsa)
222 int i = countExt.get(them);
224 countExt.set(them, i - 1);
226 if (q->error == DNS::ERROR_NO_RECORDS || q->error == DNS::ERROR_DOMAIN_NOT_FOUND)
228 ConfEntry->stats_misses++;
232 ServerInstance->SNO->WriteGlobalSno('d', "An error occurred whilst checking whether %s (%s) is on the '%s' DNS blacklist: %s",
233 them->GetFullRealHost().c_str(), them->GetIPString().c_str(), ConfEntry->name.c_str(), this->manager->GetErrorStr(q->error).c_str());
237 typedef std::vector<reference<DNSBLConfEntry> > DNSBLConfList;
239 class ModuleDNSBL : public Module, public Stats::EventListener
241 DNSBLConfList DNSBLConfEntries;
242 dynamic_reference<DNS::Manager> DNS;
243 LocalStringExt nameExt;
244 LocalIntExt countExt;
247 * Convert a string to EnumBanaction
249 DNSBLConfEntry::EnumBanaction str2banaction(const std::string &action)
251 if(action.compare("KILL")==0)
252 return DNSBLConfEntry::I_KILL;
253 if(action.compare("KLINE")==0)
254 return DNSBLConfEntry::I_KLINE;
255 if(action.compare("ZLINE")==0)
256 return DNSBLConfEntry::I_ZLINE;
257 if(action.compare("GLINE")==0)
258 return DNSBLConfEntry::I_GLINE;
259 if(action.compare("MARK")==0)
260 return DNSBLConfEntry::I_MARK;
262 return DNSBLConfEntry::I_UNKNOWN;
266 : Stats::EventListener(this)
268 , nameExt("dnsbl_match", ExtensionItem::EXT_USER, this)
269 , countExt("dnsbl_pending", ExtensionItem::EXT_USER, this)
273 void init() CXX11_OVERRIDE
275 ServerInstance->SNO->EnableSnomask('d', "DNSBL");
278 Version GetVersion() CXX11_OVERRIDE
280 return Version("Provides handling of DNS blacklists", VF_VENDOR);
283 /** Fill our conf vector with data
285 void ReadConfig(ConfigStatus& status) CXX11_OVERRIDE
287 DNSBLConfList newentries;
289 ConfigTagList dnsbls = ServerInstance->Config->ConfTags("dnsbl");
290 for(ConfigIter i = dnsbls.first; i != dnsbls.second; ++i)
292 ConfigTag* tag = i->second;
293 reference<DNSBLConfEntry> e = new DNSBLConfEntry();
295 e->name = tag->getString("name");
296 e->ident = tag->getString("ident");
297 e->host = tag->getString("host");
298 e->reason = tag->getString("reason");
299 e->domain = tag->getString("domain");
301 if (stdalgo::string::equalsci(tag->getString("type"), "bitmask"))
303 e->type = DNSBLConfEntry::A_BITMASK;
304 e->bitmask = tag->getUInt("bitmask", 0, 0, UINT_MAX);
308 memset(e->records, 0, sizeof(e->records));
309 e->type = DNSBLConfEntry::A_RECORD;
310 irc::portparser portrange(tag->getString("records"), false);
312 while ((item = portrange.GetToken()))
313 e->records[item] = 1;
316 e->banaction = str2banaction(tag->getString("action"));
317 e->duration = tag->getDuration("duration", 60, 1);
319 /* Use portparser for record replies */
321 /* yeah, logic here is a little messy */
322 if ((e->bitmask <= 0) && (DNSBLConfEntry::A_BITMASK == e->type))
324 throw ModuleException("Invalid <dnsbl:bitmask> at " + tag->getTagLocation());
326 else if (e->name.empty())
328 throw ModuleException("Empty <dnsbl:name> at " + tag->getTagLocation());
330 else if (e->domain.empty())
332 throw ModuleException("Empty <dnsbl:domain> at " + tag->getTagLocation());
334 else if (e->banaction == DNSBLConfEntry::I_UNKNOWN)
336 throw ModuleException("Unknown <dnsbl:action> at " + tag->getTagLocation());
340 if (e->reason.empty())
342 std::string location = tag->getTagLocation();
343 ServerInstance->SNO->WriteGlobalSno('d', "DNSBL(%s): empty reason, using defaults", location.c_str());
344 e->reason = "Your IP has been blacklisted.";
347 /* add it, all is ok */
348 newentries.push_back(e);
352 DNSBLConfEntries.swap(newentries);
355 void OnSetUserIP(LocalUser* user) CXX11_OVERRIDE
357 if ((user->exempt) || !DNS)
360 // Clients can't be in a DNSBL if they aren't connected via IPv4 or IPv6.
361 if (user->client_sa.family() != AF_INET && user->client_sa.family() != AF_INET6)
366 if (!user->MyClass->config->getBool("usednsbl", true))
370 ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "User has no connect class in OnSetUserIP");
372 std::string reversedip;
373 if (user->client_sa.family() == AF_INET)
375 unsigned int a, b, c, d;
376 d = (unsigned int) (user->client_sa.in4.sin_addr.s_addr >> 24) & 0xFF;
377 c = (unsigned int) (user->client_sa.in4.sin_addr.s_addr >> 16) & 0xFF;
378 b = (unsigned int) (user->client_sa.in4.sin_addr.s_addr >> 8) & 0xFF;
379 a = (unsigned int) user->client_sa.in4.sin_addr.s_addr & 0xFF;
381 reversedip = ConvToStr(d) + "." + ConvToStr(c) + "." + ConvToStr(b) + "." + ConvToStr(a);
383 else if (user->client_sa.family() == AF_INET6)
385 const unsigned char* ip = user->client_sa.in6.sin6_addr.s6_addr;
387 std::string buf = BinToHex(ip, 16);
388 for (std::string::const_reverse_iterator it = buf.rbegin(); it != buf.rend(); ++it)
390 reversedip.push_back(*it);
391 reversedip.push_back('.');
393 reversedip.erase(reversedip.length() - 1, 1);
398 ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, "Reversed IP %s -> %s", user->GetIPString().c_str(), reversedip.c_str());
400 countExt.set(user, DNSBLConfEntries.size());
402 // For each DNSBL, we will run through this lookup
403 for (unsigned i = 0; i < DNSBLConfEntries.size(); ++i)
405 // Fill hostname with a dnsbl style host (d.c.b.a.domain.tld)
406 std::string hostname = reversedip + "." + DNSBLConfEntries[i]->domain;
408 /* now we'd need to fire off lookups for `hostname'. */
409 DNSBLResolver *r = new DNSBLResolver(*this->DNS, this, nameExt, countExt, hostname, user, DNSBLConfEntries[i]);
412 this->DNS->Process(r);
414 catch (DNS::Exception &ex)
417 ServerInstance->Logs->Log(MODNAME, LOG_DEBUG, ex.GetReason());
425 ModResult OnSetConnectClass(LocalUser* user, ConnectClass* myclass) CXX11_OVERRIDE
428 if (!myclass->config->readString("dnsbl", dnsbl))
429 return MOD_RES_PASSTHRU;
431 std::string* match = nameExt.get(user);
433 return MOD_RES_PASSTHRU;
435 if (InspIRCd::Match(*match, dnsbl))
436 return MOD_RES_PASSTHRU;
441 ModResult OnCheckReady(LocalUser *user) CXX11_OVERRIDE
443 if (countExt.get(user))
445 return MOD_RES_PASSTHRU;
448 ModResult OnStats(Stats::Context& stats) CXX11_OVERRIDE
450 if (stats.GetSymbol() != 'd')
451 return MOD_RES_PASSTHRU;
453 unsigned long total_hits = 0, total_misses = 0;
455 for (std::vector<reference<DNSBLConfEntry> >::const_iterator i = DNSBLConfEntries.begin(); i != DNSBLConfEntries.end(); ++i)
457 total_hits += (*i)->stats_hits;
458 total_misses += (*i)->stats_misses;
460 stats.AddRow(304, "DNSBLSTATS DNSbl \"" + (*i)->name + "\" had " +
461 ConvToStr((*i)->stats_hits) + " hits and " + ConvToStr((*i)->stats_misses) + " misses");
464 stats.AddRow(304, "DNSBLSTATS Total hits: " + ConvToStr(total_hits));
465 stats.AddRow(304, "DNSBLSTATS Total misses: " + ConvToStr(total_misses));
467 return MOD_RES_PASSTHRU;
471 MODULE_INIT(ModuleDNSBL)