diff options
Diffstat (limited to 'include')
| -rw-r--r-- | include/dns.h | 106 |
1 files changed, 101 insertions, 5 deletions
diff --git a/include/dns.h b/include/dns.h index 834f401ae..7c128602f 100644 --- a/include/dns.h +++ b/include/dns.h @@ -40,7 +40,14 @@ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA #include "socket.h" #include "base.h" +/** + * Result status, used internally + */ typedef std::pair<int,std::string> DNSResult; + +/** + * Information on a completed lookup, used internally + */ typedef std::pair<unsigned char*, std::string> DNSInfo; /** @@ -55,14 +62,29 @@ enum ResolverError RESOLVER_BADIP = 4 }; +/** + * A DNS request + */ class DNSRequest; + +/** + * A DNS packet header + */ class DNSHeader; + +/** + * A DNS Resource Record (rr) + */ class ResourceRecord; -/* A set of requests keyed by request id */ +/** + * A set of requests keyed by request id + */ typedef std::map<int,DNSRequest*> requestlist; -/* An iterator into a set of requests */ +/** + * An iterator into a set of requests + */ typedef requestlist::iterator requestlist_iter; /** @@ -92,7 +114,7 @@ class Resolver : public Extensible */ std::string server; /** - * The ID allocated to your lookup. This is a pseud-random number + * The ID allocated to your lookup. This is a pseudo-random number * between 0 and 65535, a value of -1 indicating a failure. * The core uses this to route results to the correct objects. */ @@ -143,7 +165,9 @@ class Resolver : public Extensible int GetId(); }; -/* Query and resource record types */ +/** + * Query and resource record types + */ enum QueryType { DNS_QUERY_A = 1, /* 'A' record: an IP address */ @@ -159,29 +183,101 @@ class DNS : public Extensible { private: - static const int MAX_REQUEST_ID = 65535; + /** + * The maximum value of a dns request id, + * 16 bits wide, 0xFFFF. + */ + static const int MAX_REQUEST_ID = 0xFFFF; + /** + * Requests that are currently 'in flight + */ requestlist requests; + + /** + * Server address being used currently + */ insp_inaddr myserver; + + /** + * File descriptor being used to perform queries + */ static int MasterSocket; + + /** + * A counter used to form part of the pseudo-random id + */ int currid; + + /** + * Currently active Resolver classes + */ Resolver* Classes[MAX_REQUEST_ID]; + + /** + * Build a dns packet payload + */ int MakePayload(const char* name, const QueryType rr, const unsigned short rr_class, unsigned char* payload); public: + /** + * 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); + /** + * Get the master socket fd, used internally + */ static int GetMasterSocket(); + /** + * Start the lookup of an ip from a hostname + */ int GetIP(const char* name); + + /** + * Start the lookup of a hostname from an ip + */ int GetName(const insp_inaddr* ip); + + /** + * Fetch the result string (an ip or host) + * and/or an error message to go with it. + */ DNSResult GetResult(); + + /** + * Handle a SocketEngine read event + */ void MarshallReads(int fd); + + /** + * Add a Resolver* to the list of active classes + */ bool AddResolverClass(Resolver* r); + + /** + * Add a query to the list to be sent + */ DNSRequest* AddQuery(DNSHeader *header, int &id); + + /** + * The constructor initialises the dns socket, + * and clears the request lists. + */ DNS(); + + /** + * Destructor + */ ~DNS(); }; |