ldaptools.php

<?php
// https://blogs.msdn.microsoft.com/oldnewthing/20040315-00/?p=40253/
function sid2bin($sid) {
	if (!preg_match('/^S-(25[0-5]|2[0-4][0-9]|1?[0-9]{1,2})(-[1-9][0-9]*){3,255}$/', $sid)) throw new Exception('Not an sid');
	$segments = explode('-', $sid);

	$str = pack('hhnN', $segments[1], sizeof($segments)-3, $segments[2] >> 32, $segments[2]);
	for($i=3;$i<sizeof($segments);$i++) {
		$str .= pack('V', $segments[$i]);
	}
	return $str;
}

function bin2sid($bin) {
	if (strlen($bin) % 4) throw new Exception('Not an sid');
	$authority = unpack('J', "\0\0" . substr($bin, 2, 6));
	$segments = ['S', ord($bin[0]), $authority[1]];
	for($i=8;$i<strlen($bin);$i+=4) {
		$data = unpack('V', substr($bin, $i, $i+4));
		$segments[] = $data[1];
	}
	if (ord($bin[1]) !== sizeof($segments)-3) throw new Exception('Not an sid');
	return implode('-', $segments);
}

function objectguid2bin($objectguid) {
	if (!preg_match('/^[0-9a-z]{8}(-[0-9a-z]{4}){4}[0-9a-z]{8}$/i', $objectguid)) throw new Exception('Not an objectguid');
	$bin = hex2bin(str_replace('-', '', $objectguid));
	return reverseguid($bin);
}

function reverseguid($bin) {
	return $bin{3} . $bin{2} . $bin{1} . $bin{0}
		. $bin{5} . $bin{4}
		. $bin{7} . $bin{6}
		. substr($bin, 8);
}

function bin2objectguid($bin) {
	if (strlen($bin) !== 16) throw new Exception('Not an objectguid');
	$bin = reverseguid($bin);
	$segments = str_split(bin2hex($bin), 2);
	$segments[3] .= '-';
	$segments[5] .= '-';
	$segments[7] .= '-';
	$segments[9] .= '-';
	return implode('', $segments);
}