From: Miek Gieben Date: Thu, 28 Apr 2005 10:16:16 +0000 (+0000) Subject: converted overview to docbook X-Git-Tag: release-0.50~55 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=249babdcee6f9fe69ba2b572f4cb6ba9ef452074;p=thirdparty%2Fldns.git converted overview to docbook --- diff --git a/doc/overview.docbook b/doc/overview.docbook index f0194361..83a3e67d 100644 --- a/doc/overview.docbook +++ b/doc/overview.docbook @@ -100,7 +100,7 @@ high level resemblances to that package. The Different Parts of ldns -
+ - CLIENT - Any program making use of ldns _________/\ /\ /\ @@ -129,29 +129,53 @@ high level resemblances to that package. - DNSSEC module - sign() verify() -
+ Currently not there: -o A zone structure -o A encoder/decoder object which can be overloaded to + + + +A zone structure + + + + +A encoder/decoder object which can be overloaded to use specific functions. NSD likes to have this -o Dynamic update function + + + + +Dynamic update function + + + + + +Central Structures + -3. CENTRAL structures - + + nlnetlabs.nl. 600 IN MX 10 open.nlnetlabs.nl. \ \ \ \ \_ _/ _owner _ttl _klass _type \_ rdf[] _/ (rdf) (uint16_t) (rr_class) (rr_type) 10 := rdf[0] open.nlnetlabs.nl. := rdf[1] + + -* rdf structure: + + +rdf Structure + + The LHS is put in a rdf structure, which is a normal rdf but always has the type LDNS_RDF_TYPE_DNAME. @@ -162,79 +186,144 @@ The RSH (rdata) is put in an array of rdf's (in this case 2). The entire resource record is put in a RR structure, which has the fields described above (under the RR): - _owner (nlnetlabs.nl.) - _ttl (600) - _klass (LDNS_RR_CLASS_IN: 'IN') + _owner (nlnetlabs.nl.) + _ttl (600) + _klass (LDNS_RR_CLASS_IN: 'IN') _type (LDNS_RR_TYPE_MX: 'MX') - _rd_count (2) + _rd_count (2) _rdata_fields[rd_count] rdf[0] (10) rdf[1] (open.nlnetlabs.nl.) + + -* RR list structure: + + +RR list Structure + + An RR list structure is simply structure with a counter and an array of RR structures. Different kinds of RR's can be grouped together this way. + + -* RR set structure + + +RR set Structure + + An RR set structure is an RR list structure, but its accessor -function check if the RR's in there are: +function check if the RR's in there are: - from the same type - have the same TTL - have the same ownername This is the RFC definition of an RRset. + + -* pkt structure: -A pkt structure consists out of a header structure where -packet specific flags are kept, TC, RD, IP from server which + + +pkt Structure + + +A pkt structure consists out of a header structure where +packet specific flags are kept, TC, RD, IP address from server which sent the packet, etc. Further more it is divided in 4 sections: question, authority, answer and additional. All four sections have the type RRlist that simply hold a list of RR's + + + -4. WIRE module and CENTRAL structures Interface + + +WIRE module and CENTRAL structures Interface + + As the WIRE module takes care of the compression/decompression it needs a buffer which holds all the binary DNS data. All functions will operate on such a buffer to extract specific information which is then stored in RR structures. + + -5. RESOLVER module and CENTRAL structures Interface + + +RESOLVER module and CENTRAL structures Interface + + The resolver module always returns a pkt structure. Either with the answer or a SERVFAIL pkt. -The exact function-call parameters have not yet been +The exact function-call parameters have not yet been decided on. Also the resolver module will need to access some of the to_wire and from_wire function to creates ldn_pkt's from the data it receives (arrow not drawn). + + -6. STR module and CENTRAL structures Interface + + +STR module and CENTRAL structures Interface + + Convert to and from strings. This module could be used to read in a zone file (list of RRs) and convert the text strings to the format used by ldns. Or the other way around. + + -7. NET Module and RESOLVER module Interface + + +NET Module and RESOLVER module Interface + + The resolver module will get a packet and will mold it so that -it can be sent off to a nameserver. +it can be sent off to a nameserver. It might need to interface with the wire module (arrow not drawn). + + + + 8. NET Module and OS/libc Interface -OS/network calls will be used here. The Net module is the only part of -the library where the underlying OS matters. + + +OS/network calls will be used here. The Net module is the only part of +the library where the underlying OS matters. + + -9. Client program ldns Interface + + +Client Program ldns Interface + + Any client program will have access to - WIRE module - CENTRAL structure - RESOLVER module - STR module (arrow not drawn in the above figure) + + -10. DNSSEC module + + +DNSSEC Module + + The DNSSEC types are handled in the RR module, but the crypto routines are contained in this module. This module will depend -on OpenSSL for the crypto routines. +on OpenSSL for the crypto routines. + + + +