File Coverage

blib/lib/Crypt/Keyczar/Verifier.pm

Criterion	Covered	Total	%
statement	33	37	89.1
branch	10	14	71.4
condition	4	9	44.4
subroutine	5	5	100.0
pod	0	1	0.0
total	52	66	78.7

package Crypt::Keyczar::Verifier;
use base 'Crypt::Keyczar';
use strict;
use warnings;
use Carp;


sub verify {
    my $self = shift;
    my ($data, $signature, $hidden) = @_;

    if (!defined $signature || length $signature < Crypt::Keyczar::HEADER_SIZE()) {
        croak "signature is short";
    }

    my $hash_size = Crypt::Keyczar::KEY_HASH_SIZE();
    my ($v, $hash, $mac) = unpack "C1 a$hash_size a*", $signature;
    if ($v != Crypt::Keyczar::FORMAT_VERSION()) {
        croak "bad format version: $v";
    }
    my $key = $self->get_key($hash);
    if (!$key) {
        croak "key not found";
    }

    my $engine = $key->get_engine();
    my $expiration_time;
    if ($key->can('digest_size') && length $mac > $key->digest_size) {
        ($expiration_time, $mac) = unpack "N1 a*", $mac;
        $engine->update(pack 'N1', $expiration_time);
    }
    if (defined $hidden && length $hidden > 0) {
        $engine->update($hidden);
    }
    $engine->update($data);
    $engine->update(Crypt::Keyczar::FORMAT_BYTES());
    my $result = $engine->verify($mac);
    return $result if !$result;
    if (defined $expiration_time) {
        return time() < $expiration_time;
    }
    return $result;
}

1;
__END__