#!/usr/bin/perl
#
# Copyright (c) 2017 Gareth Palmer <gareth.palmer3@gmail.com>
# This program is free software, distributed under the terms of
# the GNU General Public License Version 2.

use strict;
use POSIX qw/EXIT_FAILURE EXIT_SUCCESS/;
use English qw/-no_match_vars/;
use IO::File;
use Crypt::OpenSSL::X509 qw/FORMAT_ASN1 FORMAT_PEM/;
use Digest;

eval {
    my $certificate_file = shift;
    die 'No certificate file specified' unless (length $certificate_file);

    my ($file, $content);
    
    unless ($file = IO::File->new ($certificate_file, '<:raw')) {
        die 'Unable to read ' . $certificate_file . ': ' . $OS_ERROR;
    }

    $content = do {local $INPUT_RECORD_SEPARATOR; $file->getline};
    $file->close;

    my $x509 = Crypt::OpenSSL::X509->new_from_string ($content, FORMAT_PEM);
    die 'Unable to load record x509 certificate' unless ($x509);
    
    my $digest = Digest->new ('SHA-1');

    $digest->add ($x509->as_string (FORMAT_ASN1));
    print $digest->b64digest, "\n";
};

if (length $EVAL_ERROR) {
    $EVAL_ERROR =~ s/ at \S+ line \d+\.//;
    warn $EVAL_ERROR;

    exit EXIT_FAILURE;
}

exit EXIT_SUCCESS;