ParagonIE_Sodium_Core_XChaCha20

10class ParagonIE_Sodium_Core_XChaCha20 extends ParagonIE_Sodium_Core_HChaCha2011{12    /**13     * @internal You should not use this directly from another application14     *15     * @param int $len16     * @param string $nonce17     * @param string $key18     * @return string19     * @throws SodiumException20     * @throws TypeError21     */22    public static function stream($len, $nonce, $key)23    {24        if (self::strlen($nonce) !== 24) {25            throw new SodiumException('Nonce must be 24 bytes long');26        }27        return self::encryptBytes(28            new ParagonIE_Sodium_Core_ChaCha20_Ctx(29                self::hChaCha20(30                    self::substr($nonce, 0, 16),31                    $key32                ),33                self::substr($nonce, 16, 8)34            ),35            str_repeat("\x00", $len)36        );37    }38 39    /**40     * @internal You should not use this directly from another application41     *42     * @param int $len43     * @param string $nonce44     * @param string $key45     * @return string46     * @throws SodiumException47     * @throws TypeError48     */49    public static function ietfStream($len, $nonce, $key)50    {51        if (self::strlen($nonce) !== 24) {52            throw new SodiumException('Nonce must be 24 bytes long');53        }54        return self::encryptBytes(55            new ParagonIE_Sodium_Core_ChaCha20_IetfCtx(56                self::hChaCha20(57                    self::substr($nonce, 0, 16),58                    $key59                ),60                "\x00\x00\x00\x00" . self::substr($nonce, 16, 8)61            ),62            str_repeat("\x00", $len)63        );64    }65 66    /**67     * @internal You should not use this directly from another application68     *69     * @param string $message70     * @param string $nonce71     * @param string $key72     * @param string $ic73     * @return string74     * @throws SodiumException75     * @throws TypeError76     */77    public static function streamXorIc($message, $nonce, $key, $ic = '')78    {79        if (self::strlen($nonce) !== 24) {80            throw new SodiumException('Nonce must be 24 bytes long');81        }82        return self::encryptBytes(83            new ParagonIE_Sodium_Core_ChaCha20_Ctx(84                self::hChaCha20(self::substr($nonce, 0, 16), $key),85                self::substr($nonce, 16, 8),86                $ic87            ),88            $message89        );