X-Git-Url: https://git.netwichtig.de/gitweb/?a=blobdiff_plain;f=include%2Fdns.h;h=e5f721770ce50553a64ee663cfba17372f23a620;hb=86ce62c9e6ea6db43703ee5017dd4acd323e9959;hp=562a493221c23eb91a6d92206a8c8f594058f646;hpb=2fe4636fa44ad48b801d0e38b892c0e47998327d;p=user%2Fhenk%2Fcode%2Finspircd.git diff --git a/include/dns.h b/include/dns.h index 562a49322..e5f721770 100644 --- a/include/dns.h +++ b/include/dns.h @@ -52,14 +52,28 @@ class Module; /** * Result status, used internally */ -class DNSResult : public classbase +class CoreExport DNSResult : public classbase { public: + /** Result ID + */ int id; + /** Result body, a hostname or IP address + */ std::string result; + /** Time-to-live value of the result + */ unsigned long ttl; + /** The original request, a hostname or IP address + */ std::string original; + /** Build a DNS result. + * @param i The request ID + * @param res The request result, a hostname or IP + * @param timetolive The request time-to-live + * @param orig The original request, a hostname or IP + */ DNSResult(int i, const std::string &res, unsigned long timetolive, const std::string &orig) : id(i), result(res), ttl(timetolive), original(orig) { } }; @@ -68,29 +82,44 @@ class DNSResult : public classbase */ typedef std::pair DNSInfo; -/** Cached item +/** Cached item stored in the query cache. */ -class CachedQuery +class CoreExport CachedQuery { public: + /** The cached result data, an IP or hostname + */ std::string data; + /** The time when the item is due to expire + */ time_t expires; + /** Build a cached query + * @param res The result data, an IP or hostname + * @param ttl The time-to-live value of the query result + */ CachedQuery(const std::string &res, unsigned int ttl) : data(res) { expires = time(NULL) + ttl; } + /** Returns the number of seconds remaining before this + * cache item has expired and should be removed. + */ int CalcTTLRemaining() { - int n = expires - time(NULL); + int n = (int)expires - (int)time(NULL); return (n < 0 ? 0 : n); } }; -/** DNS cache information +/** DNS cache information. Holds IPs mapped to hostnames, and hostnames mapped to IPs. */ +#ifndef WIN32 typedef nspace::hash_map > dnscache; +#else +typedef nspace::hash_map > dnscache; +#endif /** * Error types that class Resolver can emit to its error method. @@ -119,31 +148,29 @@ class DNSHeader; /** * A DNS Resource Record (rr) */ -class ResourceRecord; +struct ResourceRecord; /** * Query and resource record types */ enum QueryType { - DNS_QUERY_NONE = 0, /* Uninitialized Query */ - DNS_QUERY_A = 1, /* 'A' record: an ipv4 address */ - DNS_QUERY_CNAME = 5, /* 'CNAME' record: An alias */ - DNS_QUERY_PTR = 12, /* 'PTR' record: a hostname */ - DNS_QUERY_AAAA = 28, /* 'AAAA' record: an ipv6 address */ - - DNS_QUERY_PTR4 = 0xFFFD, /* Force 'PTR' to use IPV4 scemantics */ - DNS_QUERY_PTR6 = 0xFFFE, /* Force 'PTR' to use IPV6 scemantics */ + DNS_QUERY_NONE = 0, /* Uninitialized Query */ + DNS_QUERY_A = 1, /* 'A' record: an ipv4 address */ + DNS_QUERY_CNAME = 5, /* 'CNAME' record: An alias */ + DNS_QUERY_PTR = 12, /* 'PTR' record: a hostname */ + DNS_QUERY_AAAA = 28, /* 'AAAA' record: an ipv6 address */ + + DNS_QUERY_PTR4 = 0xFFFD, /* Force 'PTR' to use IPV4 scemantics */ + DNS_QUERY_PTR6 = 0xFFFE, /* Force 'PTR' to use IPV6 scemantics */ }; #ifdef IPV6 const QueryType DNS_QUERY_FORWARD = DNS_QUERY_AAAA; -const QueryType DNS_QUERY_REVERSE = DNS_QUERY_PTR; #else const QueryType DNS_QUERY_FORWARD = DNS_QUERY_A; -const QueryType DNS_QUERY_REVERSE = DNS_QUERY_PTR; #endif - +const QueryType DNS_QUERY_REVERSE = DNS_QUERY_PTR; /** * Used internally to force PTR lookups to use a certain protocol scemantics, * e.g. x.x.x.x.in-addr.arpa for v4, and *.ip6.arpa for v6. @@ -164,7 +191,7 @@ enum ForceProtocol * can occur by calling virtual methods, one is a success situation, and the other * an error situation. */ -class Resolver : public Extensible +class CoreExport Resolver : public Extensible { protected: /** @@ -277,12 +304,15 @@ class Resolver : public Extensible * this method will return -1. */ int GetId(); - /** * Returns the creator module, or NULL */ Module* GetCreator(); - + /** + * If the result is a cached result, this triggers the objects + * OnLookupComplete. This is done because it is not safe to call + * the abstract virtual method from the constructor. + */ void TriggerCachedResult(); }; @@ -291,10 +321,13 @@ class Resolver : public Extensible * back to Resolver objects, based upon the request ID. You * should never use this class yourself. */ -class DNS : public EventHandler +class CoreExport DNS : public EventHandler { private: + /** + * Creator/Owner object + */ InspIRCd* ServerInstance; /** @@ -303,11 +336,6 @@ class DNS : public EventHandler */ static const int MAX_REQUEST_ID = 0xFFFF; - /** - * Server address being used currently - */ - insp_inaddr myserver; - /** * A counter used to form part of the pseudo-random id */ @@ -326,6 +354,9 @@ class DNS : public EventHandler */ dnscache* cache; + /** A timer which ticks every hour to remove expired + * items from the DNS cache. + */ class CacheTimer* PruneTimer; /** @@ -334,14 +365,26 @@ class DNS : public EventHandler int MakePayload(const char* name, const QueryType rr, const unsigned short rr_class, unsigned char* payload); public: + + /** + * Server address being used currently + */ + int socketfamily; +#ifdef IPV6 + in6_addr myserver6; +#endif + in_addr myserver4; + /** * Currently active Resolver classes */ Resolver* Classes[MAX_REQUEST_ID]; + /** * Requests that are currently 'in flight' */ DNSRequest* requests[MAX_REQUEST_ID]; + /** * The port number DNS requests are made on, * and replies have as a source-port number. @@ -352,14 +395,17 @@ class DNS : public EventHandler * Fill an rr (resource record) with data from input */ static void FillResourceRecord(ResourceRecord* rr, const unsigned char* input); + /** * Fill a header with data from input limited by a length */ static void FillHeader(DNSHeader *header, const unsigned char *input, const int length); + /** * Empty out a header into a data stream ready for transmission "on the wire" */ static void EmptyHeader(unsigned char *output, const DNSHeader *header, const int length); + /** * Start the lookup of an ipv4 from a hostname */ @@ -447,11 +493,26 @@ class DNS : public EventHandler */ void CleanResolvers(Module* module); + /** Return the cached value of an IP or hostname + * @param source An IP or hostname to find in the cache. + * @return A pointer to a CachedQuery if the item exists, + * otherwise NULL. + */ CachedQuery* GetCache(const std::string &source); + /** Delete a cached item from the DNS cache. + * @param source An IP or hostname to remove + */ void DelCache(const std::string &source); + /** Clear all items from the DNS cache immediately. + */ int ClearCache(); + + /** Prune the DNS cache, e.g. remove all expired + * items and rehash the cache buckets, but leave + * items in the hash which are still valid. + */ int PruneCache(); };