——package
Net::DNS::RR::APL;
#
# $Id: APL.pm 1390 2015-09-11 11:42:11Z willem $
#
$VERSION
= (
qw$LastChangedRevision: 1390 $
)[1];
use
strict;
=head1 NAME
Net::DNS::RR::APL - DNS APL resource record
=cut
use
integer;
use
Carp;
sub
_decode_rdata {
## decode rdata from wire-format octet string
my
$self
=
shift
;
my
(
$data
,
$offset
) =
@_
;
my
$limit
=
$offset
+
$self
->{rdlength};
my
$aplist
=
$self
->{aplist} = [];
while
(
$offset
<
$limit
) {
my
$xlen
=
unpack
"\@$offset x3 C"
,
$$data
;
my
$size
= (
$xlen
& 0x7F );
my
$item
=
bless
{},
'Net::DNS::RR::APL::Item'
;
$item
->negate(1)
if
$xlen
& 0x80;
@{
$item
}{
qw(family prefix address)
} =
unpack
"\@$offset n C x a$size"
,
$$data
;
$offset
+=
$size
+ 4;
push
@$aplist
,
$item
;
}
croak(
'corrupt APL data'
)
unless
$offset
==
$limit
;
# more or less FUBAR
}
sub
_encode_rdata {
## encode rdata as wire-format octet string
my
$self
=
shift
;
my
@rdata
;
my
$aplist
=
$self
->{aplist} || [];
foreach
(
@$aplist
) {
my
$address
=
$_
->{address};
my
$xlength
=
$_
->negate |
length
(
$address
);
push
@rdata
,
pack
'n C2 a*'
, @{
$_
}{
qw(family prefix)
},
$xlength
,
$address
;
}
join
''
,
@rdata
;
}
sub
_format_rdata {
## format rdata portion of RR string.
my
$self
=
shift
;
my
$aplist
=
$self
->{aplist} || [];
my
@rdata
=
map
$_
->string,
@$aplist
;
}
sub
_parse_rdata {
## populate RR from rdata in argument list
my
$self
=
shift
;
$self
->aplist(
@_
);
}
sub
aplist {
my
$self
=
shift
;
while
(
scalar
@_
) {
# parse apitem strings
last
unless
$_
[0] =~ m
#^(!?)(\d+):(.+)/(\d+)$#;
my
$n
= $1 ? 1 : 0;
my
$f
= $2;
my
(
$x
,
$a
,
$p
) =
split
m
#^[^:]+:|/#, shift;
$self
->aplist(
negate
=>
$n
,
family
=>
$f
,
address
=>
$a
,
prefix
=>
$p
);
}
my
$aplist
=
$self
->{aplist} ||= [];
if
(
my
%argval
=
@_
) {
# parse attribute=value list
my
$item
=
bless
{},
'Net::DNS::RR::APL::Item'
;
while
(
my
(
$attribute
,
$value
) =
each
%argval
) {
$item
->
$attribute
(
$value
)
unless
$attribute
eq
'address'
;
}
$item
->address(
$argval
{address} );
# address must be last
push
@$aplist
,
$item
;
}
my
@ap
=
@$aplist
;
return
wantarray
?
@ap
:
join
' '
,
map
$_
->string,
@ap
if
defined
wantarray
;
}
########################################
package
Net::DNS::RR::APL::Item;
sub
negate {
my
$bit
= 0x80;
for
(
shift
->{negate} ) {
my
$set
=
$bit
| (
$_
||= 0 );
return
$bit
&
$_
unless
scalar
@_
;
$_
= (
shift
) ?
$set
: (
$set
^
$bit
);
return
$_
&
$bit
;
}
}
sub
family {
my
$self
=
shift
;
$self
->{family} = 0 +
shift
if
scalar
@_
;
$self
->{family} || 0;
}
sub
prefix {
my
$self
=
shift
;
$self
->{prefix} = 0 +
shift
if
scalar
@_
;
$self
->{prefix} || 0;
}
{
sub
_address_1 {
my
$self
=
shift
;
my
$A
=
bless
{
%$self
},
'Net::DNS::RR::A'
;
return
$A
->address
unless
scalar
@_
;
my
$alength
= (
$self
->prefix + 7 ) >> 3;
# mask non-prefix bits, suppress nulls
my
@address
=
unpack
"C$alength"
,
$A
->address(
shift
);
my
$bitmask
= 0xFF << ( 8 -
$self
->prefix & 7 );
push
@address
, (
$bitmask
&
pop
(
@address
) )
if
$alength
;
for
(
reverse
@address
) {
last
if
$_
;
pop
@address
}
$self
->{address} =
pack
'C*'
,
@address
;
}
sub
_address_2 {
my
$self
=
shift
;
my
$AAAA
=
bless
{
%$self
},
'Net::DNS::RR::AAAA'
;
return
$AAAA
->address_long
unless
scalar
@_
;
my
$alength
= (
$self
->prefix + 7 ) >> 3;
# mask non-prefix bits, suppress nulls
my
@address
=
unpack
"C$alength"
,
$AAAA
->address(
shift
);
my
$bitmask
= 0xFF << ( 8 -
$self
->prefix & 7 );
push
@address
, (
$bitmask
&
pop
(
@address
) )
if
$alength
;
for
(
reverse
@address
) {
last
if
$_
;
pop
@address
}
$self
->{address} =
pack
'C*'
,
@address
;
}
}
sub
address {
for
(
$_
[0]->family ) {
return
&_address_1
if
/1/;
return
&_address_2
if
/2/;
die
'unknown address family'
;
}
}
sub
string {
my
$self
=
shift
;
my
$not
=
$self
->negate ?
'!'
:
''
;
my
(
$family
,
$address
,
$prefix
) = (
$self
->family,
$self
->address,
$self
->prefix );
return
"$not$family:$address/$prefix"
;
}
1;
__END__
=head1 SYNOPSIS
use Net::DNS;
$rr = new Net::DNS::RR('name IN APL aplist');
=head1 DESCRIPTION
DNS Address Prefix List (APL) record
=head1 METHODS
The available methods are those inherited from the base class augmented
by the type-specific methods defined in this package.
Use of undocumented package features or direct access to internal data
structures is discouraged and could result in program termination or
other unpredictable behaviour.
=head2 aplist
@aplist = $rr->aplist;
@aplist = $rr->aplist( '1:192.168.32.0/21', '!1:192.168.38.0/28' );
@aplist = $rr->aplist( '1:224.0.0.0/4', '2:FF00:0:0:0:0:0:0:0/8' );
@aplist = $rr->aplist( negate => 1,
family => 1,
address => '192.168.38.0',
prefix => 28,
);
Ordered, possibly empty, list of address prefix items.
Additional items, if present, are appended to the existing list
with neither prefix aggregation nor reordering.
=head2 Net::DNS::RR::APL::Item
Each element of the prefix list is a Net::DNS::RR::APL::Item
object which is inextricably bound to the APL record which
created it.
=head2 negate
$rr->negate(1);
if ( $rr->negate ) {
...
}
Boolean attribute indicating the prefix to be an address range exclusion.
=head2 family
$family = $rr->family;
$rr->family( $family );
Address family discriminant.
=head2 prefix
$prefix = $rr->prefix;
$rr->prefix( $prefix );
Number of bits comprising the address prefix.
=head2 address
$address = $object->address;
Address portion of the prefix list item.
=head2 string
$string = $object->string;
Returns the prefix list item in the form required in zone files.
=head1 COPYRIGHT
Copyright (c)2008 Olaf Kolkman, NLnet Labs.
Portions Copyright (c)2011 Dick Franks.
All rights reserved.
Package template (c)2009,2012 O.M.Kolkman and R.W.Franks.
=head1 LICENSE
Permission to use, copy, modify, and distribute this software and its
documentation for any purpose and without fee is hereby granted, provided
that the above copyright notice appear in all copies and that both that
copyright notice and this permission notice appear in supporting
documentation, and that the name of the author not be used in advertising
or publicity pertaining to distribution of the software without specific
prior written permission.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
DEALINGS IN THE SOFTWARE.
=head1 SEE ALSO
L<perl>, L<Net::DNS>, L<Net::DNS::RR>, RFC3123
=cut