<?php
if (class_exists('ParagonIE_Sodium_Core32_XChaCha20', false)) {
return;
}
/**
* Class ParagonIE_Sodium_Core32_XChaCha20
*/
class ParagonIE_Sodium_Core32_XChaCha20 extends ParagonIE_Sodium_Core32_HChaCha20
{
/**
* @internal You should not use this directly from another application
*
* @param int $len
* @param string $nonce
* @param string $key
* @return string
* @throws SodiumException
* @throws TypeError
*/
public static function stream($len = 64, $nonce = '', $key = '')
{
if (self::strlen($nonce) !== 24) {
throw new SodiumException('Nonce must be 24 bytes long');
}
return self::encryptBytes(
new ParagonIE_Sodium_Core32_ChaCha20_Ctx(
self::hChaCha20(
self::substr($nonce, 0, 16),
$key
),
self::substr($nonce, 16, 8)
),
str_repeat("\x00", $len)
);
}
/**
* @internal You should not use this directly from another application
*
* @param string $message
* @param string $nonce
* @param string $key
* @param string $ic
* @return string
* @throws SodiumException
* @throws TypeError
*/
public static function streamXorIc($message, $nonce = '', $key = '', $ic = '')
{
if (self::strlen($nonce) !== 24) {
throw new SodiumException('Nonce must be 24 bytes long');
}
return self::encryptBytes(
new ParagonIE_Sodium_Core32_ChaCha20_Ctx(
self::hChaCha20(self::substr($nonce, 0, 16), $key),
self::substr($nonce, 16, 8),
$ic
),
$message
);
}
}