<?php
if (class_exists('ParagonIE_Sodium_Core_XSalsa20', false)) {
return;
}
/**
* Class ParagonIE_Sodium_Core_XSalsa20
*/
abstract class ParagonIE_Sodium_Core_XSalsa20 extends ParagonIE_Sodium_Core_HSalsa20
{
/**
* Expand a key and nonce into an xsalsa20 keystream.
*
* @internal You should not use this directly from another application
*
* @param int $len
* @param string $nonce
* @param string $key
* @return string
* @throws SodiumException
* @throws TypeError
*/
public static function xsalsa20($len, $nonce, $key)
{
$ret = self::salsa20(
$len,
self::substr($nonce, 16, 8),
self::hsalsa20($nonce, $key)
);
return $ret;
}
/**
* Encrypt a string with XSalsa20. Doesn't provide integrity.
*
* @internal You should not use this directly from another application
*
* @param string $message
* @param string $nonce
* @param string $key
* @return string
* @throws SodiumException
* @throws TypeError
*/
public static function xsalsa20_xor($message, $nonce, $key)
{
return self::xorStrings(
$message,
self::xsalsa20(
self::strlen($message),
$nonce,
$key
)
);
}
}