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Diffstat (limited to 'include/modules/dns.h')
| -rw-r--r-- | include/modules/dns.h | 204 |
1 files changed, 204 insertions, 0 deletions
diff --git a/include/modules/dns.h b/include/modules/dns.h new file mode 100644 index 000000000..f3bf45916 --- /dev/null +++ b/include/modules/dns.h @@ -0,0 +1,204 @@ +/* + * InspIRCd -- Internet Relay Chat Daemon + * + * Copyright (C) 2013 Adam <Adam@anope.org> + * Copyright (C) 2003-2013 Anope Team <team@anope.org> + * + * 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 <http://www.gnu.org/licenses/>. + */ + +#pragma once + +namespace DNS +{ + /** Valid query types + */ + enum QueryType + { + /* Nothing */ + QUERY_NONE, + /* A simple A lookup */ + QUERY_A = 1, + /* A CNAME lookup */ + QUERY_CNAME = 5, + /* Reverse DNS lookup */ + QUERY_PTR = 12, + /* TXT */ + QUERY_TXT = 16, + /* IPv6 AAAA lookup */ + QUERY_AAAA = 28 + }; + + /** Flags that can be AND'd into DNSPacket::flags to receive certain values + */ + enum + { + QUERYFLAGS_QR = 0x8000, + QUERYFLAGS_OPCODE = 0x7800, + QUERYFLAGS_AA = 0x400, + QUERYFLAGS_TC = 0x200, + QUERYFLAGS_RD = 0x100, + QUERYFLAGS_RA = 0x80, + QUERYFLAGS_Z = 0x70, + QUERYFLAGS_RCODE = 0xF + }; + + enum Error + { + ERROR_NONE, + ERROR_UNKNOWN, + ERROR_UNLOADED, + ERROR_TIMEDOUT, + ERROR_MALFORMED, + ERROR_NOT_AN_ANSWER, + ERROR_NONSTANDARD_QUERY, + ERROR_FORMAT_ERROR, + ERROR_SERVER_FAILURE, + ERROR_DOMAIN_NOT_FOUND, + ERROR_NOT_IMPLEMENTED, + ERROR_REFUSED, + ERROR_NO_RECORDS, + ERROR_INVALIDTYPE + }; + + typedef uint16_t RequestId; + + const int PORT = 53; + + class Exception : public ModuleException + { + public: + Exception(const std::string& message) : ModuleException(message) { } + }; + + struct Question + { + std::string name; + QueryType type; + + Question() : type(QUERY_NONE) { } + Question(const std::string& n, QueryType t) : name(n), type(t) { } + bool operator==(const Question& other) const { return ((name == other.name) && (type == other.type)); } + bool operator!=(const Question& other) const { return (!(*this == other)); } + + struct hash + { + size_t operator()(const Question& question) const + { + return irc::insensitive()(question.name); + } + }; + }; + + struct ResourceRecord : Question + { + unsigned int ttl; + std::string rdata; + time_t created; + + ResourceRecord(const std::string& n, QueryType t) : Question(n, t), ttl(0), created(ServerInstance->Time()) { } + ResourceRecord(const Question& question) : Question(question), ttl(0), created(ServerInstance->Time()) { } + }; + + struct Query + { + Question question; + std::vector<ResourceRecord> answers; + Error error; + bool cached; + + Query() : error(ERROR_NONE), cached(false) { } + Query(const Question& q) : question(q), error(ERROR_NONE), cached(false) { } + + const ResourceRecord* FindAnswerOfType(QueryType qtype) const + { + for (std::vector<DNS::ResourceRecord>::const_iterator i = answers.begin(); i != answers.end(); ++i) + { + const DNS::ResourceRecord& rr = *i; + if (rr.type == qtype) + return &rr; + } + + return NULL; + } + }; + + class ReplySocket; + class Request; + + /** DNS manager + */ + class Manager : public DataProvider + { + public: + Manager(Module* mod) : DataProvider(mod, "DNS") { } + + virtual void Process(Request* req) = 0; + virtual void RemoveRequest(Request* req) = 0; + virtual std::string GetErrorStr(Error) = 0; + }; + + /** A DNS query. + */ + class Request : public Timer + { + protected: + Manager* const manager; + public: + Question question; + /* Use result cache if available */ + bool use_cache; + /* Request id */ + RequestId id; + /* Creator of this request */ + Module* const creator; + + Request(Manager* mgr, Module* mod, const std::string& addr, QueryType qt, bool usecache = true) + : Timer(ServerInstance->Config->ConfValue("dns")->getDuration("timeout", 5, 1)) + , manager(mgr) + , question(addr, qt) + , use_cache(usecache) + , id(0) + , creator(mod) + { + } + + virtual ~Request() + { + manager->RemoveRequest(this); + } + + /** Called when this request succeeds + * @param r The query sent back from the nameserver + */ + virtual void OnLookupComplete(const Query* req) = 0; + + /** Called when this request fails or times out. + * @param r The query sent back from the nameserver, check the error code. + */ + virtual void OnError(const Query* req) { } + + /** Used to time out the query, calls OnError and asks the TimerManager + * to delete this request + */ + bool Tick(time_t now) + { + Query rr(this->question); + rr.error = ERROR_TIMEDOUT; + this->OnError(&rr); + delete this; + return false; + } + }; + +} // namespace DNS |