| Current Path : /usr/share/perl5/Crypt/DSA/ |
| Current File : //usr/share/perl5/Crypt/DSA/Key.pm |
package Crypt::DSA::Key;
use strict;
use Math::BigInt 1.78 try => 'GMP, Pari';
use Carp qw( croak );
use Crypt::DSA::Util qw( bitsize );
use vars qw{$VERSION};
BEGIN {
$VERSION = '1.17';
}
sub new {
my $class = shift;
my %param = @_;
my $key = bless { }, $class;
if ($param{Filename} || $param{Content}) {
if ($param{Filename} && $param{Content}) {
croak "Filename and Content are mutually exclusive.";
}
return $key->read(%param);
}
$key;
}
sub size { bitsize($_[0]->p) }
BEGIN {
no strict 'refs';
for my $meth (qw( p q g pub_key priv_key r kinv )) {
*$meth = sub {
my($key, $value) = @_;
if (ref $value eq 'Math::Pari') {
$key->{$meth} = Math::Pari::pari2pv($value);
}
elsif (ref $value) {
$key->{$meth} = "$value";
}
elsif ($value) {
if ($value =~ /^0x/) {
$key->{$meth} = Math::BigInt->new($value)->bstr;
}
else {
$key->{$meth} = $value;
}
} elsif (@_ > 1 && !defined $value) {
delete $key->{$meth};
}
my $ret = $key->{$meth} || "";
$ret = Math::BigInt->new("$ret") if $ret =~ /^\d+$/;
$ret;
};
}
}
sub read {
my $key = shift;
my %param = @_;
my $type = $param{Type} or croak "read: Need a key file 'Type'";
my $class = join '::', __PACKAGE__, $type;
eval "use $class;";
croak "Invalid key file type '$type': $@" if $@;
bless $key, $class;
local *FH;
if (my $fname = delete $param{Filename}) {
open FH, $fname or return;
my $blob = do { local $/; <FH> };
close FH;
$param{Content} = $blob;
}
$key->deserialize(%param);
}
sub write {
my $key = shift;
my %param = @_;
my $type;
unless ($type = $param{Type}) {
my $pkg = __PACKAGE__;
($type) = ref($key) =~ /^${pkg}::(\w+)$/;
}
croak "write: Need a key file 'Type'" unless $type;
my $class = join '::', __PACKAGE__, $type;
eval "use $class;";
croak "Invalid key file type '$type': $@" if $@;
bless $key, $class;
my $blob = $key->serialize(%param);
if (my $fname = delete $param{Filename}) {
local *FH;
open FH, ">$fname" or croak "Can't open $fname: $!";
print FH $blob;
close FH;
}
$blob;
}
1;
__END__
=head1 NAME
Crypt::DSA::Key - DSA key
=head1 SYNOPSIS
use Crypt::DSA::Key;
my $key = Crypt::DSA::Key->new;
$key->p($p);
=head1 DESCRIPTION
I<Crypt::DSA::Key> contains a DSA key, both the public and
private portions. Subclasses of I<Crypt::DSA::Key> implement
I<read> and I<write> methods, such that you can store DSA
keys on disk, and read them back into your application.
=head1 USAGE
Any of the key attributes can be accessed through combination
get/set methods. The key attributes are: I<p>, I<q>, I<g>,
I<priv_key>, and I<pub_key>. For example:
$key->p($p);
my $p2 = $key->p;
=head2 $key = Crypt::DSA::Key->new(%arg)
Creates a new (empty) key object. All of the attributes are
initialized to 0.
Alternately, if you provide the I<Filename> parameter (see
below), the key will be read in from disk. If you provide
the I<Type> parameter (mandatory if I<Filename> is provided),
be aware that your key will actually be blessed into a subclass
of I<Crypt::DSA::Key>. Specifically, it will be the class
implementing the specific read functionality for that type,
eg. I<Crypt::DSA::Key::PEM>.
Returns the key on success, C<undef> otherwise. (See I<Password>
for one reason why I<new> might return C<undef>).
I<%arg> can contain:
=over 4
=item * Type
The type of file where the key is stored. Currently the only
option is I<PEM>, which indicates a PEM file (optionally
encrypted, ASN.1-encoded object). Support for reading/writing
PEM files comes from I<Convert::PEM>; if you don't have this
module installed, the I<new> method will die.
This argument is mandatory, I<if> you're either reading the file from
disk (ie. you provide a I<Filename> argument) or you've specified the
I<Content> argument.
=item * Filename
The location of the file from which you'd like to read the key.
Requires a I<Type> argument so the decoder knows what type of file it
is. You can't specify I<Content> and I<Filename> at the same time.
=item * Content
The serialized version of the key. Requires a I<Type> argument so the
decoder knows how to decode it. You can't specify I<Content> and
I<Filename> at the same time.
=item * Password
If your key file is encrypted, you'll need to supply a
passphrase to decrypt it. You can do that here.
If your passphrase is incorrect, I<new> will return C<undef>.
=back
=head2 $key->write(%arg)
Writes a key (optionally) to disk, using a format that you
define with the I<Type> parameter.
If your I<$key> object has a defined I<priv_key> (private key portion),
the key will be written as a DSA private key object; otherwise, it will
be written out as a public key. Note that not all serialization mechanisms
can produce public keys in this version--currently, only PEM public keys
are supported.
I<%arg> can include:
=over 4
=item * Type
The type of file format that you wish to write. I<PEM> is one
example (in fact, currently, it's the only example).
This argument is mandatory, I<unless> your I<$key> object is
already blessed into a subclass (eg. I<Crypt::DSA::Key::PEM>),
and you wish to write the file using the same subclass.
=item * Filename
The location of the file on disk where you want the key file
to be written.
=item * Password
If you want the key file to be encrypted, provide this
argument, and the ASN.1-encoded string will be encrypted using
the passphrase as a key.
=back
=head2 $key->size
Returns the size of the key, in bits. This is actually the
number of bits in the large prime I<p>.
=head1 AUTHOR & COPYRIGHTS
Please see the Crypt::DSA manpage for author, copyright,
and license information.
=cut
Copyright 2K16 - 2K18 Indonesian Hacker Rulez
;?>)