The Rise of Contactless Payments:...
In recent years, contactless payments have surged in popularity, driven...
<?php
namespace PhpOffice\PhpSpreadsheet\Reader\Xls;
class MD5
{
/**
* @var int
*/
private $a;
/**
* @var int
*/
private $b;
/**
* @var int
*/
private $c;
/**
* @var int
*/
private $d;
/**
* @var int
*/
private static $allOneBits;
/**
* MD5 stream constructor.
*/
public function __construct()
{
self::$allOneBits = self::signedInt(0xffffffff);
$this->reset();
}
/**
* Reset the MD5 stream context.
*/
public function reset(): void
{
$this->a = 0x67452301;
$this->b = self::signedInt(0xEFCDAB89);
$this->c = self::signedInt(0x98BADCFE);
$this->d = 0x10325476;
}
/**
* Get MD5 stream context.
*
* @return string
*/
public function getContext()
{
$s = '';
foreach (['a', 'b', 'c', 'd'] as $i) {
$v = $this->{$i};
$s .= chr($v & 0xff);
$s .= chr(($v >> 8) & 0xff);
$s .= chr(($v >> 16) & 0xff);
$s .= chr(($v >> 24) & 0xff);
}
return $s;
}
/**
* Add data to context.
*
* @param string $data Data to add
*/
public function add(string $data): void
{
// @phpstan-ignore-next-line
$words = array_values(unpack('V16', $data));
$A = $this->a;
$B = $this->b;
$C = $this->c;
$D = $this->d;
$F = [self::class, 'f'];
$G = [self::class, 'g'];
$H = [self::class, 'h'];
$I = [self::class, 'i'];
// ROUND 1
self::step($F, $A, $B, $C, $D, $words[0], 7, 0xd76aa478);
self::step($F, $D, $A, $B, $C, $words[1], 12, 0xe8c7b756);
self::step($F, $C, $D, $A, $B, $words[2], 17, 0x242070db);
self::step($F, $B, $C, $D, $A, $words[3], 22, 0xc1bdceee);
self::step($F, $A, $B, $C, $D, $words[4], 7, 0xf57c0faf);
self::step($F, $D, $A, $B, $C, $words[5], 12, 0x4787c62a);
self::step($F, $C, $D, $A, $B, $words[6], 17, 0xa8304613);
self::step($F, $B, $C, $D, $A, $words[7], 22, 0xfd469501);
self::step($F, $A, $B, $C, $D, $words[8], 7, 0x698098d8);
self::step($F, $D, $A, $B, $C, $words[9], 12, 0x8b44f7af);
self::step($F, $C, $D, $A, $B, $words[10], 17, 0xffff5bb1);
self::step($F, $B, $C, $D, $A, $words[11], 22, 0x895cd7be);
self::step($F, $A, $B, $C, $D, $words[12], 7, 0x6b901122);
self::step($F, $D, $A, $B, $C, $words[13], 12, 0xfd987193);
self::step($F, $C, $D, $A, $B, $words[14], 17, 0xa679438e);
self::step($F, $B, $C, $D, $A, $words[15], 22, 0x49b40821);
// ROUND 2
self::step($G, $A, $B, $C, $D, $words[1], 5, 0xf61e2562);
self::step($G, $D, $A, $B, $C, $words[6], 9, 0xc040b340);
self::step($G, $C, $D, $A, $B, $words[11], 14, 0x265e5a51);
self::step($G, $B, $C, $D, $A, $words[0], 20, 0xe9b6c7aa);
self::step($G, $A, $B, $C, $D, $words[5], 5, 0xd62f105d);
self::step($G, $D, $A, $B, $C, $words[10], 9, 0x02441453);
self::step($G, $C, $D, $A, $B, $words[15], 14, 0xd8a1e681);
self::step($G, $B, $C, $D, $A, $words[4], 20, 0xe7d3fbc8);
self::step($G, $A, $B, $C, $D, $words[9], 5, 0x21e1cde6);
self::step($G, $D, $A, $B, $C, $words[14], 9, 0xc33707d6);
self::step($G, $C, $D, $A, $B, $words[3], 14, 0xf4d50d87);
self::step($G, $B, $C, $D, $A, $words[8], 20, 0x455a14ed);
self::step($G, $A, $B, $C, $D, $words[13], 5, 0xa9e3e905);
self::step($G, $D, $A, $B, $C, $words[2], 9, 0xfcefa3f8);
self::step($G, $C, $D, $A, $B, $words[7], 14, 0x676f02d9);
self::step($G, $B, $C, $D, $A, $words[12], 20, 0x8d2a4c8a);
// ROUND 3
self::step($H, $A, $B, $C, $D, $words[5], 4, 0xfffa3942);
self::step($H, $D, $A, $B, $C, $words[8], 11, 0x8771f681);
self::step($H, $C, $D, $A, $B, $words[11], 16, 0x6d9d6122);
self::step($H, $B, $C, $D, $A, $words[14], 23, 0xfde5380c);
self::step($H, $A, $B, $C, $D, $words[1], 4, 0xa4beea44);
self::step($H, $D, $A, $B, $C, $words[4], 11, 0x4bdecfa9);
self::step($H, $C, $D, $A, $B, $words[7], 16, 0xf6bb4b60);
self::step($H, $B, $C, $D, $A, $words[10], 23, 0xbebfbc70);
self::step($H, $A, $B, $C, $D, $words[13], 4, 0x289b7ec6);
self::step($H, $D, $A, $B, $C, $words[0], 11, 0xeaa127fa);
self::step($H, $C, $D, $A, $B, $words[3], 16, 0xd4ef3085);
self::step($H, $B, $C, $D, $A, $words[6], 23, 0x04881d05);
self::step($H, $A, $B, $C, $D, $words[9], 4, 0xd9d4d039);
self::step($H, $D, $A, $B, $C, $words[12], 11, 0xe6db99e5);
self::step($H, $C, $D, $A, $B, $words[15], 16, 0x1fa27cf8);
self::step($H, $B, $C, $D, $A, $words[2], 23, 0xc4ac5665);
// ROUND 4
self::step($I, $A, $B, $C, $D, $words[0], 6, 0xf4292244);
self::step($I, $D, $A, $B, $C, $words[7], 10, 0x432aff97);
self::step($I, $C, $D, $A, $B, $words[14], 15, 0xab9423a7);
self::step($I, $B, $C, $D, $A, $words[5], 21, 0xfc93a039);
self::step($I, $A, $B, $C, $D, $words[12], 6, 0x655b59c3);
self::step($I, $D, $A, $B, $C, $words[3], 10, 0x8f0ccc92);
self::step($I, $C, $D, $A, $B, $words[10], 15, 0xffeff47d);
self::step($I, $B, $C, $D, $A, $words[1], 21, 0x85845dd1);
self::step($I, $A, $B, $C, $D, $words[8], 6, 0x6fa87e4f);
self::step($I, $D, $A, $B, $C, $words[15], 10, 0xfe2ce6e0);
self::step($I, $C, $D, $A, $B, $words[6], 15, 0xa3014314);
self::step($I, $B, $C, $D, $A, $words[13], 21, 0x4e0811a1);
self::step($I, $A, $B, $C, $D, $words[4], 6, 0xf7537e82);
self::step($I, $D, $A, $B, $C, $words[11], 10, 0xbd3af235);
self::step($I, $C, $D, $A, $B, $words[2], 15, 0x2ad7d2bb);
self::step($I, $B, $C, $D, $A, $words[9], 21, 0xeb86d391);
$this->a = ($this->a + $A) & self::$allOneBits;
$this->b = ($this->b + $B) & self::$allOneBits;
$this->c = ($this->c + $C) & self::$allOneBits;
$this->d = ($this->d + $D) & self::$allOneBits;
}
private static function f(int $X, int $Y, int $Z): int
{
return ($X & $Y) | ((~$X) & $Z); // X AND Y OR NOT X AND Z
}
private static function g(int $X, int $Y, int $Z): int
{
return ($X & $Z) | ($Y & (~$Z)); // X AND Z OR Y AND NOT Z
}
private static function h(int $X, int $Y, int $Z): int
{
return $X ^ $Y ^ $Z; // X XOR Y XOR Z
}
private static function i(int $X, int $Y, int $Z): int
{
return $Y ^ ($X | (~$Z)); // Y XOR (X OR NOT Z)
}
/** @param float|int $t may be float on 32-bit system */
private static function step(callable $func, int &$A, int $B, int $C, int $D, int $M, int $s, $t): void
{
$t = self::signedInt($t);
$A = (int) ($A + call_user_func($func, $B, $C, $D) + $M + $t) & self::$allOneBits;
$A = self::rotate($A, $s);
$A = (int) ($B + $A) & self::$allOneBits;
}
/** @param float|int $result may be float on 32-bit system */
private static function signedInt($result): int
{
return is_int($result) ? $result : (int) (PHP_INT_MIN + $result - 1 - PHP_INT_MAX);
}
private static function rotate(int $decimal, int $bits): int
{
$binary = str_pad(decbin($decimal), 32, '0', STR_PAD_LEFT);
return self::signedInt(bindec(substr($binary, $bits) . substr($binary, 0, $bits)));
}
}
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