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package Net::DNS::RR::SSHFP;
#
# $Id: SSHFP.pm 388 2005-06-22 10:06:05Z olaf $
#
use strict;
BEGIN {
eval { require bytes; }
}
use vars qw(@ISA $VERSION $HasBabble);
BEGIN {
eval {
require Digest::BubbleBabble;
Digest::BubbleBabble->import(qw(bubblebabble))
};
$HasBabble = $@ ? 0 : 1;
}
$VERSION = (qw$LastChangedRevision: 388 $)[1];
@ISA = qw(Net::DNS::RR);
my %algtype = (
RSA => 1,
DSA => 2,
);
my %fingerprinttype = (
'SHA-1' => 1,
);
my %fingerprinttypebyval = reverse %fingerprinttype;
my %algtypebyval = reverse %algtype;
sub new {
my ($class, $self, $data, $offset) = @_;
if ($self->{'rdlength'} > 0) {
my $offsettoalg = $offset;
my $offsettofptype = $offset+1;
my $offsettofp = $offset+2;
my $fplength = 20; # This will need to change if other fingerprint types
# are being deployed.
$self->{'algorithm'} = unpack('C', substr($$data, $offsettoalg, 1));
$self->{'fptype'} = unpack('C', substr($$data, $offsettofptype, 1));
die "This fingerprint type $self->{'fptype'} has not yet been implemented\n." .
"Contact developer of Net::DNS::RR::SSHFP.\n"
unless defined $fingerprinttypebyval{$self->{'fptype'}};
# All this is SHA-1 dependend
$self->{'fpbin'} = substr($$data,$offsettofp, $fplength); # SHA1 digest 20 bytes long
$self->{'fingerprint'} = uc unpack('H*', $self->{'fpbin'});
}
return bless $self, $class;
}
sub new_from_string {
my ($class, $self, $string) = @_;
if ($string) {
$string =~ tr/()//d;
$string =~ s/;.*$//mg;
$string =~ s/\n//g;
@{$self}{qw(algorithm fptype fingerprint)} = split(m/\s+/, $string, 3);
# We allow spaces in the fingerprint.
$self->{'fingerprint'} =~ s/\s//g;
}
return bless $self, $class;
}
sub rdatastr {
my $self = shift;
my $rdatastr = '';
if (exists $self->{"algorithm"}) {
$rdatastr = join(' ', @{$self}{qw(algorithm fptype fingerprint)})
.' ; ' . $self->babble;
}
return $rdatastr;
}
sub rr_rdata {
my $self = shift;
if (exists $self->{"algorithm"}) {
return pack('C2', @{$self}{qw(algorithm fptype)}) . $self->fpbin;
}
return '';
}
sub babble {
my $self = shift;
if ($HasBabble) {
return bubblebabble(Digest => $self->fpbin);
} else {
return "";
}
}
sub fpbin {
my ($self) = @_;
return $self->{'fpbin'} ||= pack('H*', $self->{'fingerprint'});
}
1;
=head1 NAME
Net::DNS::RR::SSHFP - DNS SSHFP resource record
=head1 SYNOPSIS
C<use Net::DNS::RR>;
=head1 DESCRIPTION
Class for Delegation signer (SSHFP) resource records.
=head1 METHODS
In addition to the regular methods
=head2 algorithm
print "algoritm" = ", $rr->algorithm, "\n";
Returns the RR's algorithm field in decimal representation
1 = RSA
2 = DSS
=head2 fingerprint
print "fingerprint" = ", $rr->fingerprint, "\n";
Returns the SHA1 fingerprint over the label and key in hexadecimal
representation.
=head2 fpbin
$fpbin = $rr->fpbin;
Returns the fingerprint as binary material.
=head2 fptype
print "fingerprint type" . " = " . $rr->fptype ."\n";
Returns the fingerprint type of the SSHFP RR.
=head2 babble
print $rr->babble;
If Digest::BubbleBabble is available on the sytem this method returns the
'BabbleBubble' representation of the fingerprint. The 'BabbleBubble'
string may be handy for telephone confirmation.
The 'BabbleBubble' string returned as a comment behind the RDATA when
the string method is called.
The method returns an empty string if Digest::BubbleBable is not installed.
=head1 TODO
=head1 ACKNOWLEDGEMENT
Jakob Schlyter for code review and supplying patches.
=head1 COPYRIGHT
Copyright (c) 2004 RIPE NCC, Olaf Kolkman.
"All rights reserved, This program is free software; you may redistribute it
and/or modify it under the same terms as Perl itself.
=head1 SEE ALSO
L<perl(1)>, L<Net::DNS>, L<Net::DNS::Resolver>, L<Net::DNS::Packet>,
L<Net::DNS::Header>, L<Net::DNS::Question>, L<Net::DNS::RR>,
draft-ietf-dnssext-delegation-signer
=cut
|
