Files
wp-multisite-waas/dependencies/paragonie/constant_time_encoding/src/Hex.php
2024-11-30 18:24:12 -07:00

125 lines
4.3 KiB
PHP

<?php
declare (strict_types=1);
namespace WP_Ultimo\Dependencies\ParagonIE\ConstantTime;
use RangeException;
use TypeError;
/**
* Copyright (c) 2016 - 2022 Paragon Initiative Enterprises.
* Copyright (c) 2014 Steve "Sc00bz" Thomas (steve at tobtu dot com)
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
/**
* Class Hex
* @package ParagonIE\ConstantTime
*/
abstract class Hex implements EncoderInterface
{
/**
* Convert a binary string into a hexadecimal string without cache-timing
* leaks
*
* @param string $binString (raw binary)
* @return string
* @throws TypeError
*/
public static function encode(string $binString) : string
{
$hex = '';
$len = Binary::safeStrlen($binString);
for ($i = 0; $i < $len; ++$i) {
/** @var array<int, int> $chunk */
$chunk = \unpack('C', $binString[$i]);
$c = $chunk[1] & 0xf;
$b = $chunk[1] >> 4;
$hex .= \pack('CC', 87 + $b + ($b - 10 >> 8 & ~38), 87 + $c + ($c - 10 >> 8 & ~38));
}
return $hex;
}
/**
* Convert a binary string into a hexadecimal string without cache-timing
* leaks, returning uppercase letters (as per RFC 4648)
*
* @param string $binString (raw binary)
* @return string
* @throws TypeError
*/
public static function encodeUpper(string $binString) : string
{
$hex = '';
$len = Binary::safeStrlen($binString);
for ($i = 0; $i < $len; ++$i) {
/** @var array<int, int> $chunk */
$chunk = \unpack('C', $binString[$i]);
$c = $chunk[1] & 0xf;
$b = $chunk[1] >> 4;
$hex .= \pack('CC', 55 + $b + ($b - 10 >> 8 & ~6), 55 + $c + ($c - 10 >> 8 & ~6));
}
return $hex;
}
/**
* Convert a hexadecimal string into a binary string without cache-timing
* leaks
*
* @param string $encodedString
* @param bool $strictPadding
* @return string (raw binary)
* @throws RangeException
*/
public static function decode(string $encodedString, bool $strictPadding = \false) : string
{
$hex_pos = 0;
$bin = '';
$c_acc = 0;
$hex_len = Binary::safeStrlen($encodedString);
$state = 0;
if (($hex_len & 1) !== 0) {
if ($strictPadding) {
throw new RangeException('Expected an even number of hexadecimal characters');
} else {
$encodedString = '0' . $encodedString;
++$hex_len;
}
}
/** @var array<int, int> $chunk */
$chunk = \unpack('C*', $encodedString);
while ($hex_pos < $hex_len) {
++$hex_pos;
$c = $chunk[$hex_pos];
$c_num = $c ^ 48;
$c_num0 = $c_num - 10 >> 8;
$c_alpha = ($c & ~32) - 55;
$c_alpha0 = ($c_alpha - 10 ^ $c_alpha - 16) >> 8;
if (($c_num0 | $c_alpha0) === 0) {
throw new RangeException('Expected hexadecimal character');
}
$c_val = $c_num0 & $c_num | $c_alpha & $c_alpha0;
if ($state === 0) {
$c_acc = $c_val * 16;
} else {
$bin .= \pack('C', $c_acc | $c_val);
}
$state ^= 1;
}
return $bin;
}
}