ParagonIE_Sodium_Core_ChaCha20_Ctx example

    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_Core_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 int $len * @param string $nonce * @param string $key * @return string * @throws SodiumException * @throws TypeError */

    public static function stream($len = 64, $nonce = '', $key = '')
    {
        return self::encryptBytes(
            new ParagonIE_Sodium_Core_ChaCha20_Ctx($key, $nonce),
            str_repeat("\x00", $len)
        );
    }

    /** * @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 */