kodedphp / stdlib

UUID.php

<?php declare(strict_types=1);

/*
 * This file is part of the Koded package.
 *
 * (c) Mihail Binev <mihail@kodeart.com>
 *
 * Please view the LICENSE distributed with this source code
 * for the full copyright and license information.
 */

namespace Koded\Stdlib;

use InvalidArgumentException;

/**
 * Class UUID generates Universally Unique Identifiers following the RFC 4122.
 *
 * The 5 fields of the UUID v1
 *  - 32 bit, *time_low*
 *  - 16 bit, *time_mid*
 *  - 16 bit, *time_high_and_version*
 *  - 16 bit, (8 bits for *clock_seq_and_reserved* + 8 bits for *clock_seq_low*)
 *  - 48 bit, *node*
 *
 * @link    http://tools.ietf.org/html/rfc4122
 * @link    https://docs.python.org/2/library/uuid.html
 * @link    https://en.wikipedia.org/wiki/Universally_unique_identifier
 */
final class UUID
{
    /* @link http://tools.ietf.org/html/rfc4122#appendix-C */

    /**
     * When this namespace is specified, the name string
     * is a fully-qualified domain name.
     */
    const NAMESPACE_DNS = '6ba7b810-9dad-11d1-80b4-00c04fd430c8';

    /**
     * When this namespace is specified, the name string is a URL.
     */
    const NAMESPACE_URL = '6ba7b811-9dad-11d1-80b4-00c04fd430c8';

    /**
     * When this namespace is specified, the name string is an ISO OID.
     */
    const NAMESPACE_OID = '6ba7b812-9dad-11d1-80b4-00c04fd430c8';

    /**
     * When this namespace is specified, the name string is
     * an X.500 DN in DER or a text output format.
     */
    const NAMESPACE_X500 = '6ba7b814-9dad-11d1-80b4-00c04fd430c8';

    /**
     * Regex pattern for UUIDs
     */
    const PATTERN = '[a-f0-9]{8}\-[a-f0-9]{4}\-[1|3|4|5][a-f0-9]{3}\-[a-f0-9]{4}\-[a-f0-9]{12}';

    /**
     * UUID v1 is generated from host (hardware address), clock sequence and
     * current time. This is very slow method.
     *
     * @param int|string $address [optional] 48 bit number for the hardware address.
     *                            It can be an integer or hexadecimal string
     *
     * @return string UUID v1
     */
    public static function v1($address = null): string
    {
        static $matches = [[null], [null]];

        /**
         * Get the hardware address as a 48-bit positive integer.
         *
         * @param string $node [optional]
         *
         * @return null|string
         * @throws InvalidArgumentException
         */
        $node = function($node = null) use (&$matches) {
            if (null === $node) {
                if (empty($matches[1][0])) {
                    // Get MAC address (Linux server LAN)
                    $info = `ifconfig 2>&1` ?: '';

                    // Cache the info in $matches
                    preg_match_all('~[^:]([a-f0-9]{2}([:-])[a-f0-9]{2}(\2[a-f0-9]{2}){4})[^:]~i',
                        $info,
                        $matches,
                        PREG_PATTERN_ORDER
                    );
                }

                $node = $matches[1][0] ?? null;

                // Cannot identify host, fallback as in http://tools.ietf.org/html/rfc4122#section-4.5
                if (empty($node)) {
                    // @codeCoverageIgnoreStart
                    $node = sprintf('%06x%06x', mt_rand(0, 1 << 24), mt_rand(0, 1 << 24));
                    // @codeCoverageIgnoreEnd
                }
            }

            $node = str_replace([':', '-'], '', $node);

            if (ctype_digit($node)) {
                $node = sprintf('%012x', $node);
            }

            if (ctype_xdigit($node) && strlen($node) <= 12) {
                $node = strtolower(sprintf('%012s', $node));
            } else {
                throw new InvalidArgumentException('UUID invalid node value');
            }

            return $node;
        }; // end $node

        $clockSeq = function() {
            // Random 14-bit sequence number, http://tools.ietf.org/html/rfc4122#section-4.2.1.1
            return mt_rand(0, 1 << 14);
        };

        $uuidTime = function() {
            // 0x01b21dd213814000 is a 100 nanoseconds interval between UUID epoch
            // and UNIX epoch datetime (15/10/1582 00:00:01 - 01/01/1970 00:00:01)
            $time = gettimeofday();
            $time = ($time['sec'] * 10000000) + ($time['usec'] * 10) + 0x01b21dd213814000;

            return [
                'low' => sprintf('%08x', $time & 0xffffffff),
                'mid' => sprintf('%04x', ($time >> 32) & 0xffff),
                'high' => sprintf('%04x', ($time >> 48) & 0x0fff)
            ];
        };

        $uuidTime = $uuidTime();
        $clockSeq = $clockSeq();

        // Set to version 1
        $version = hexdec($uuidTime['high']) & 0x0fff;
        $version &= ~(0xf000);
        $version |= 1 << 12;

        // RFC 4122
        $variant = ($clockSeq >> 8) & 0x3f;
        $variant &= ~(0xc0);
        $variant |= 0x80;

        return sprintf('%08s-%04s-%04x-%02x%02x-%012s',
            $uuidTime['low'],
            $uuidTime['mid'],
            $version,
            $variant,
            $clockSeq & 0xff,
            $node($address)
        );
    }

    /**
     * UUID v3 (name based, MD5).
     *
     * @param string $namespace UUID namespace identifier
     * @param string $name      A name
     *
     * @return string UUID v3
     */
    public static function v3(string $namespace, string $name): string
    {
        return UUID::fromName($namespace, $name, 3);
    }

    /**
     * Version 4, pseudo-random (xxxxxxxx-xxxx-4xxx-[8|9|a|b]xxx-xxxxxxxxxxxx)
     *
     * @return string 128bit of pseudo-random UUID
     * @see http://en.wikipedia.org/wiki/UUID#Version_4_.28random.29
     * @throws \Exception
     */
    public static function v4(): string
    {
        $bytes = unpack('n*', random_bytes(16));
        $bytes[4] = $bytes[4] & 0x0fff | 0x4000;
        $bytes[5] = $bytes[5] & 0x3fff | 0x8000;

        return vsprintf('%04x%04x-%04x-%04x-%04x-%04x%04x%04x', $bytes);

It seems like $bytes can also be of type false; however, parameter $args of vsprintf() does only seem to accept array, maybe add an additional type check?

    }

    /**
     * UUID v5 (name based, SHA1).
     *
     * @param string $namespace UUID namespace identifier
     * @param string $name      A name
     *
     * @return string UUID v5
     */
    public static function v5(string $namespace, string $name): string
    {
        return UUID::fromName($namespace, $name, 5);
    }

    /**
     * Checks if a given UUID has valid format.
     *
     * @param string $uuid
     *
     * @return bool
     */
    public static function valid(string $uuid): bool
    {
        if (false === (bool)preg_match('/^' . UUID::PATTERN . '$/i', $uuid)) {
            return false;
        }

        if ('4' === $uuid[14] && false === in_array($uuid[19], ['8', '9', 'a', 'b'])) {
            return false;
        }

        return true;
    }

    /**
     * Checks if a given UUID has valid format and matches against the version.
     *
     * @param string $uuid
     * @param int    $version Check against the version 1, 3, 4 or 5
     *
     * @return bool
     */
    public static function matches(string $uuid, int $version = 4): bool
    {
        assert(in_array($version, [1, 3, 4, 5]), 'Expected UUID version 1, 3, 4 or 5');
        return UUID::valid($uuid);
    }

    /**
     * Creates the v3 and/or v5 UUID.
     *
     * @param string $namespace UUID namespace identifier (see UUID constants)
     * @param string $name      A name
     * @param int    $version   3 or 5
     *
     * @throws InvalidArgumentException
     * @return string UUID 3 or 5
     */
    private static function fromName(string $namespace, string $name, int $version): string
    {
        if (false === UUID::matches($namespace, $version)) {
            throw new InvalidArgumentException('Invalid UUID namespace ' . $namespace);
        }

        $hex = str_replace('-', '', $namespace);
        $bits = '';
        for ($i = 0, $len = strlen($hex); $i < $len; $i += 2) {
            $bits .= chr((int)hexdec($hex[$i] . $hex[$i + 1]));
        }

        $hash = $bits . $name;
        $hash = (3 === $version) ? md5($hash) : sha1($hash);

        return sprintf('%08s-%04s-%04x-%04x-%12s',
            substr($hash, 0, 8),
            substr($hash, 8, 4),
            (hexdec(substr($hash, 12, 4)) & 0x0fff) | (3 === $version ? 0x3000 : 0x5000),
            (hexdec(substr($hash, 16, 4)) & 0x3fff) | 0x8000,
            substr($hash, 20, 12)
        );
    }
}