lib::Net::DNS::UsereContributed Perl Doculib::Net::DNS::Packet(3)NAMENet::DNS::Packet - DNS packet object class
SYNOPSIS
use Net::DNS::Packet;
DESCRIPTION
A Net::DNS::Packet object represents a DNS packet.
METHODS
new
$packet = new Net::DNS::Packet(\$data);
$packet = new Net::DNS::Packet(\$data, 1); # set debugging
$packet = new Net::DNS::Packet("foo.com");
$packet = new Net::DNS::Packet("foo.com", "MX", "IN");
($packet, $err) = new Net::DNS::Packet(\$data);
If passed a reference to a scalar containing DNS packet
data, new creates a packet object from that data. A
second argument can be passed to turn on debugging output
for packet parsing.
If passed a domain, type, and class, new creates a packet
object appropriate for making a DNS query for the
requested information. The type and class can be omitted;
they default to A and IN.
If called in array context, returns a packet object and an
error string. The error string will only be defined if
the packet object is undefined (i.e., couldn't be
created).
Returns undef if unable to create a packet object (e.g.,
if the packet data is truncated).
data
$data = $packet->data;
Returns the packet data in binary format, suitable for
sending to a nameserver.
header
$header = $packet->header;
Returns a Net::DNS::Header object representing the header
section of the packet.
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lib::Net::DNS::UsereContributed Perl Doculib::Net::DNS::Packet(3)
question, zone
@question = $packet->question;
Returns a list of Net::DNS::Question objects representing
the question section of the packet.
In dynamic update packets, this section is known as zone
and specifies the zone to be updated.
answer, pre, prerequisite
@answer = $packet->answer;
Returns a list of Net::DNS::RR objects representing the
answer section of the packet.
In dynamic update packets, this section is known as pre or
prerequisite and specifies the RRs or RRsets which must or
must not preexist.
authority, update
@authority = $packet->authority;
Returns a list of Net::DNS::RR objects representing the
authority section of the packet.
In dynamic update packets, this section is known as update
and specifies the RRs or RRsets to be added or delted.
additional
@additional = $packet->additional;
Returns a list of Net::DNS::RR objects representing the
additional section of the packet.
print
$packet->print;
Prints the packet data on the standard output in an ASCII
format similar to that used in DNS zone files.
string
print $packet->string;
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lib::Net::DNS::UsereContributed Perl Doculib::Net::DNS::Packet(3)
Returns a string representation of the packet.
answerfrom
print "packet received from ", $packet->answerfrom, "\n";
Returns the IP address from which we received this packet.
User-created packets will return undef for this method.
answersize
print "packet size: ", $packet->answersize, " bytes\n";
Returns the size of the packet in bytes as it was received
from a nameserver. User-created packets will return undef
for this method (use length $packet->data instead).
push
$packet->push("pre", $rr);
$packet->push("update", $rr);
$packet->push("additional", $rr);
$packet->push("update", $rr1, $rr2, $rr3);
$packet->push("update", @rr);
Adds RRs to the specified section of the packet.
dn_comp
$compname = $packet->dn_comp("foo.bar.com", $offset);
Returns a domain name compressed for a particular packet
object, to be stored beginning at the given offset within
the packet data. The name will be added to a running list
of compressed domain names for future use.
dn_expand
use Net::DNS::Packetqw(dn_expand);
($name, $nextoffset) = dn_expand(\$data, $offset);
($name, $nextoffset) = Net::DNS::Packet::dn_expand(\$data, $offset);
Expands the domain name stored at a particular location in
a DNS packet. The first argument is a reference to a
scalar containing the packet data. The second argument is
the offset within the packet where the (possibly
compressed) domain name is stored.
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lib::Net::DNS::UsereContributed Perl Doculib::Net::DNS::Packet(3)
Returns the domain name and the offset of the next
location in the packet.
Returns (undef, undef) if the domain name couldn't be
expanded.
COPYRIGHT
Copyright (c) 1997 Michael Fuhr. All rights reserved.
This program is free software; you can redistribute it
and/or modify it under the same terms as Perl itself.
SEE ALSO
the perl(1) manpage, the Net::DNS manpage, the
Net::DNS::Resolver manpage, the Net::DNS::Update manpage,
the Net::DNS::Header manpage, the Net::DNS::Question
manpage, the Net::DNS::RR manpage, RFC 1035 Section 4.1,
RFC 2136 Section 2
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