.\" -*- mode: troff; coding: utf-8 -*- .\" Automatically generated by Pod::Man 5.01 (Pod::Simple 3.43) .\" .\" Standard preamble: .\" ======================================================================== .de Sp \" Vertical space (when we can't use .PP) .if t .sp .5v .if n .sp .. .de Vb \" Begin verbatim text .ft CW .nf .ne \\$1 .. .de Ve \" End verbatim text .ft R .fi .. .\" \*(C` and \*(C' are quotes in nroff, nothing in troff, for use with C<>. .ie n \{\ . ds C` "" . ds C' "" 'br\} .el\{\ . ds C` . ds C' 'br\} .\" .\" Escape single quotes in literal strings from groff's Unicode transform. .ie \n(.g .ds Aq \(aq .el .ds Aq ' .\" .\" If the F register is >0, we'll generate index entries on stderr for .\" titles (.TH), headers (.SH), subsections (.SS), items (.Ip), and index .\" entries marked with X<> in POD. Of course, you'll have to process the .\" output yourself in some meaningful fashion. .\" .\" Avoid warning from groff about undefined register 'F'. .de IX .. .nr rF 0 .if \n(.g .if rF .nr rF 1 .if (\n(rF:(\n(.g==0)) \{\ . if \nF \{\ . de IX . tm Index:\\$1\t\\n%\t"\\$2" .. . if !\nF==2 \{\ . nr % 0 . nr F 2 . \} . \} .\} .rr rF .\" ======================================================================== .\" .IX Title "Net::DNS::Resolver::Programmable 3" .TH Net::DNS::Resolver::Programmable 3 2023-07-25 "perl v5.38.0" "User Contributed Perl Documentation" .\" For nroff, turn off justification. Always turn off hyphenation; it makes .\" way too many mistakes in technical documents. .if n .ad l .nh .SH NAME Net::DNS::Resolver::Programmable \- programmable DNS resolver class for offline emulation of DNS .SH SYNOPSIS .IX Header "SYNOPSIS" .Vb 2 \& use Net::DNS::Resolver::Programmable; \& use Net::DNS::RR; \& \& my $resolver = Net::DNS::Resolver::Programmable\->new( \& records => { \& \*(Aqexample.com\*(Aq => [ \& Net::DNS::RR\->new(\*(Aqexample.com. NS ns.example.org.\*(Aq), \& Net::DNS::RR\->new(\*(Aqexample.com. A 192.168.0.1\*(Aq) \& ], \& \*(Aqns.example.org\*(Aq => [ \& Net::DNS::RR\->new(\*(Aqns.example.org. A 192.168.1.1\*(Aq) \& ] \& }, \& \& resolver_code => sub { \& my ($domain, $rr_type, $class) = @_; \& ... \& return ($result, $aa, @rrs); \& } \& ); .Ve .SH DESCRIPTION .IX Header "DESCRIPTION" \&\fBNet::DNS::Resolver::Programmable\fR is a \fBNet::DNS::Resolver\fR descendant class that allows a virtual DNS to be emulated instead of querying the real DNS. A set of static DNS records may be supplied, or arbitrary code may be specified as a means for retrieving DNS records, or even generating them on the fly. .SS Constructor .IX Subsection "Constructor" The following constructor is provided: .IP "\fBnew(%options)\fR: returns \fINet::DNS::Resolver::Programmable\fR" 4 .IX Item "new(%options): returns Net::DNS::Resolver::Programmable" Creates a new programmed DNS resolver object. .Sp \&\f(CW%options\fR is a list of key/value pairs representing any of the following options: .RS 4 .IP \fBrecords\fR 4 .IX Item "records" A reference to a hash of arrays containing a static set of \fINet::DNS::RR\fR objects. The hash entries must be indexed by fully qualified domain names (lower-case, without any trailing dots), and the entries themselves must be arrays of the RR objects pertaining to these domain names. For example: .Sp .Vb 12 \& records => { \& \*(Aqexample.com\*(Aq => [ \& Net::DNS::RR\->new(\*(Aqexample.com. NS ns.example.org.\*(Aq), \& Net::DNS::RR\->new(\*(Aqexample.com. A 192.168.0.1\*(Aq) \& ], \& \*(Aqwww.example.com\*(Aq => [ \& Net::DNS::RR\->new(\*(Aqwww.example.com. A 192.168.0.2\*(Aq) \& ], \& \*(Aqns.example.org\*(Aq => [ \& Net::DNS::RR\->new(\*(Aqns.example.org. A 192.168.1.1\*(Aq) \& ] \& } .Ve .Sp If this option is specified, the resolver retrieves requested RRs from this data structure. .IP \fBresolver_code\fR 4 .IX Item "resolver_code" A code reference used as a call-back for dynamically retrieving requested RRs. .Sp The code must take the following query parameters as arguments: the \fIdomain\fR, \&\fIRR type\fR, and \fIclass\fR. .Sp It must return a list composed of: the response's \fIRCODE\fR (by name, as returned by Net::DNS::Header\->rcode), the \&\fR\f(CI\*(C`aa\*(C'\fR\fI (authoritative answer) flag\fR (\fIboolean\fR, use \fBundef\fR if you don't care), and the \fINet::DNS::RR answer objects\fR. If an error string is returned instead of a valid RCODE, a \fINet::DNS::Packet\fR object is not constructed but an error condition for the resolver is signaled instead. .Sp For example: .Sp .Vb 5 \& resolver_code => sub { \& my ($domain, $rr_type, $class) = @_; \& ... \& return ($result, $aa, @rrs); \& } .Ve .Sp If both this and the \f(CW\*(C`records\*(C'\fR option are specified, then statically programmed records are used in addition to any that are returned by the configured resolver code. .IP \fBdefnames\fR 4 .IX Item "defnames" .PD 0 .IP \fBdnsrch\fR 4 .IX Item "dnsrch" .IP \fBdomain\fR 4 .IX Item "domain" .IP \fBsearchlist\fR 4 .IX Item "searchlist" .IP \fBdebug\fR 4 .IX Item "debug" .PD These Net::DNS::Resolver options are also meaningful with Net::DNS::Resolver::Programmable. See Net::DNS::Resolver for their descriptions. .RE .RS 4 .RE .SS "Instance methods" .IX Subsection "Instance methods" The following instance methods of \fINet::DNS::Resolver\fR are also supported by \&\fINet::DNS::Resolver::Programmable\fR: .IP "\fBsearch\fR: returns \fINet::DNS::Packet\fR" 4 .IX Item "search: returns Net::DNS::Packet" .PD 0 .IP "\fBquery\fR: returns \fINet::DNS::Packet\fR" 4 .IX Item "query: returns Net::DNS::Packet" .IP "\fBsend\fR: returns \fINet::DNS::Packet\fR" 4 .IX Item "send: returns Net::DNS::Packet" .PD Performs an offline DNS query, using the statically programmed DNS RRs and/or the configured dynamic resolver code. See the "new" constructor's \f(CW\*(C`records\*(C'\fR and \f(CW\*(C`resolver_code\*(C'\fR options. See the descriptions of search, query, and send for details about the calling syntax of these methods. .IP \fBprint\fR 4 .IX Item "print" .PD 0 .IP "\fBstring\fR: returns \fIstring\fR" 4 .IX Item "string: returns string" .IP "\fBsearchlist\fR: returns \fIlist\fR of \fIstring\fR" 4 .IX Item "searchlist: returns list of string" .IP "\fBdefnames\fR: returns \fIboolean\fR" 4 .IX Item "defnames: returns boolean" .IP "\fBdnsrch\fR: returns \fIboolean\fR" 4 .IX Item "dnsrch: returns boolean" .IP "\fBdebug\fR: returns \fIboolean\fR" 4 .IX Item "debug: returns boolean" .IP "\fBerrorstring\fR: returns \fIstring\fR" 4 .IX Item "errorstring: returns string" .IP "\fBanswerfrom\fR: returns \fIstring\fR" 4 .IX Item "answerfrom: returns string" .IP "\fBanswersize\fR: returns \fIinteger\fR" 4 .IX Item "answersize: returns integer" .PD See "METHODS" in Net::DNS::Resolver. .PP Currently the following methods of \fINet::DNS::Resolver\fR are \fBnot\fR supported: \&\fBaxfr\fR, \fBaxfr_start\fR, \fBaxfr_next\fR, \fBnameservers\fR, \fBport\fR, \fBsrcport\fR, \&\fBsrcaddr\fR, \fBbgsend\fR, \fBbgread\fR, \fBbgisready\fR, \fBtsig\fR, \fBretrans\fR, \fBretry\fR, \&\fBrecurse\fR, \fBusevc\fR, \fBtcp_timeout\fR, \fBudp_timeout\fR, \fBpersistent_tcp\fR, \&\fBpersistent_udp\fR, \fBigntc\fR, \fBdnssec\fR, \fBcdflag\fR, \fBudppacketsize\fR. The effects of using these on \fINet::DNS::Resolver::Programmable\fR objects are undefined. .SH "SEE ALSO" .IX Header "SEE ALSO" Net::DNS::Resolver .PP For availability, support, and license information, see the README file included with Net::DNS::Resolver::Programmable. .SH AUTHORS .IX Header "AUTHORS" David Precious (BIGPRESH) \f(CW\*(C`\*(C'\fR took on maintainership in July 2017 .PP Original author Julian Mehnle \f(CW\*(C`\*(C'\fR .SH ACKNOWLEDGEMENTS .IX Header "ACKNOWLEDGEMENTS" Dick Franks (rwfranks) .PP (This section was added by BIGPRESH in July 2017, so currently omits acknowledgements for those who contributed things in the past; I may retrospectively add them in future.)