<?php
if (class_exists('ParagonIE_Sodium_Core_HSalsa20', false)) {
return;
}
/**
* Class ParagonIE_Sodium_Core_HSalsa20
*/
abstract class ParagonIE_Sodium_Core_HSalsa20 extends ParagonIE_Sodium_Core_Salsa20
{
/**
* Calculate an hsalsa20 hash of a single block
*
* HSalsa20 doesn't have a counter and will never be used for more than
* one block (used to derive a subkey for xsalsa20).
*
* @internal You should not use this directly from another application
*
* @param string $in
* @param string $k
* @param string|null $c
* @return string
* @throws TypeError
*/
public static function hsalsa20($in, $k, $c = null)
{
if ($c === null) {
$x0 = 0x61707865;
$x5 = 0x3320646e;
$x10 = 0x79622d32;
$x15 = 0x6b206574;
} else {
$x0 = self::load_4(self::substr($c, 0, 4));
$x5 = self::load_4(self::substr($c, 4, 4));
$x10 = self::load_4(self::substr($c, 8, 4));
$x15 = self::load_4(self::substr($c, 12, 4));
}
$x1 = self::load_4(self::substr($k, 0, 4));
$x2 = self::load_4(self::substr($k, 4, 4));
$x3 = self::load_4(self::substr($k, 8, 4));
$x4 = self::load_4(self::substr($k, 12, 4));
$x11 = self::load_4(self::substr($k, 16, 4));
$x12 = self::load_4(self::substr($k, 20, 4));
$x13 = self::load_4(self::substr($k, 24, 4));
$x14 = self::load_4(self::substr($k, 28, 4));
$x6 = self::load_4(self::substr($in, 0, 4));
$x7 = self::load_4(self::substr($in, 4, 4));
$x8 = self::load_4(self::substr($in, 8, 4));
$x9 = self::load_4(self::substr($in, 12, 4));
for ($i = self::ROUNDS; $i > 0; $i -= 2) {
$x4 ^= self::rotate($x0 + $x12, 7);
$x8 ^= self::rotate($x4 + $x0, 9);
$x12 ^= self::rotate($x8 + $x4, 13);
$x0 ^= self::rotate($x12 + $x8, 18);
$x9 ^= self::rotate($x5 + $x1, 7);
$x13 ^= self::rotate($x9 + $x5, 9);
$x1 ^= self::rotate($x13 + $x9, 13);
$x5 ^= self::rotate($x1 + $x13, 18);
$x14 ^= self::rotate($x10 + $x6, 7);
$x2 ^= self::rotate($x14 + $x10, 9);
$x6 ^= self::rotate($x2 + $x14, 13);
$x10 ^= self::rotate($x6 + $x2, 18);
$x3 ^= self::rotate($x15 + $x11, 7);
$x7 ^= self::rotate($x3 + $x15, 9);
$x11 ^= self::rotate($x7 + $x3, 13);
$x15 ^= self::rotate($x11 + $x7, 18);
$x1 ^= self::rotate($x0 + $x3, 7);
$x2 ^= self::rotate($x1 + $x0, 9);
$x3 ^= self::rotate($x2 + $x1, 13);
$x0 ^= self::rotate($x3 + $x2, 18);
$x6 ^= self::rotate($x5 + $x4, 7);
$x7 ^= self::rotate($x6 + $x5, 9);
$x4 ^= self::rotate($x7 + $x6, 13);
$x5 ^= self::rotate($x4 + $x7, 18);
$x11 ^= self::rotate($x10 + $x9, 7);
$x8 ^= self::rotate($x11 + $x10, 9);
$x9 ^= self::rotate($x8 + $x11, 13);
$x10 ^= self::rotate($x9 + $x8, 18);
$x12 ^= self::rotate($x15 + $x14, 7);
$x13 ^= self::rotate($x12 + $x15, 9);
$x14 ^= self::rotate($x13 + $x12, 13);
$x15 ^= self::rotate($x14 + $x13, 18);
}
return self::store32_le($x0) .
self::store32_le($x5) .
self::store32_le($x10) .
self::store32_le($x15) .
self::store32_le($x6) .
self::store32_le($x7) .
self::store32_le($x8) .
self::store32_le($x9);
}
}