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backup / src / JetBackup / 3rdparty / phpseclib3 / Crypt / EC / Formats / Signature / IEEE.php

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IEEE.php

65 lines

1	<?php
2
3	/**
4	* IEEE P1363 Signature Handler
5	*
6	* PHP version 5
7	*
8	* Handles signatures in the format described in
9	* https://standards.ieee.org/ieee/1363/2049/ and
10	* https://developer.mozilla.org/en-US/docs/Web/API/SubtleCrypto/sign#ecdsa
11	*
12	* @author Jim Wigginton <terrafrost@php.net>
13	* @copyright 2016 Jim Wigginton
14	* @license http://www.opensource.org/licenses/mit-license.html MIT License
15	* @link http://phpseclib.sourceforge.net
16	*/
17
18	declare(strict_types=1);
19
20	namespace phpseclib3\Crypt\EC\Formats\Signature;
21
22	use phpseclib3\Math\BigInteger;
23
24	/**
25	* ASN1 Signature Handler
26	*
27	* @author Jim Wigginton <terrafrost@php.net>
28	*/
29	abstract class IEEE
30	{
31	/**
32	* Loads a signature
33	*
34	* @param string $sig
35	* @return array
36	*/
37	public static function load($sig)
38	{
39	if (!is_string($sig)) {
40	return false;
41	}
42
43	$len = strlen($sig);
44	if ($len & 1) {
45	return false;
46	}
47
48	$r = new BigInteger(substr($sig, 0, $len >> 1), 256);
49	$s = new BigInteger(substr($sig, $len >> 1), 256);
50
51	return compact('r', 's');
52	}
53
54	/**
55	* Returns a signature in the appropriate format
56	*/
57	public static function save(BigInteger $r, BigInteger $s): string
58	{
59	$r = $r->toBytes();
60	$s = $s->toBytes();
61	$len = max(strlen($r), strlen($s));
62	return str_pad($r, $len, "\0", STR_PAD_LEFT) . str_pad($s, $len, "\0", STR_PAD_LEFT);
63	}
64	}
65