ParagonIE_Sodium_Core_AEGIS_State256

14class ParagonIE_Sodium_Core_AEGIS_State25615{16    /** @var array<int, string> $state */17    protected $state;18    public function __construct()19    {20        $this->state = array_fill(0, 6, '');21    }22 23    /**24     * @internal Only use this for unit tests!25     * @return string[]26     */27    public function getState()28    {29        return array_values($this->state);30    }31 32    /**33     * @param array $input34     * @return self35     * @throws SodiumException36     *37     * @internal Only for unit tests38     */39    public static function initForUnitTests(array $input)40    {41        if (count($input) < 6) {42            throw new SodiumException('invalid input');43        }44        $state = new self();45        for ($i = 0; $i < 6; ++$i) {46            $state->state[$i] = $input[$i];47        }48        return $state;49    }50 51    /**52     * @param string $key53     * @param string $nonce54     * @return self55     */56    public static function init($key, $nonce)57    {58        $state = new self();59        $k0 = ParagonIE_Sodium_Core_Util::substr($key, 0, 16);60        $k1 = ParagonIE_Sodium_Core_Util::substr($key, 16, 16);61        $n0 = ParagonIE_Sodium_Core_Util::substr($nonce, 0, 16);62        $n1 = ParagonIE_Sodium_Core_Util::substr($nonce, 16, 16);63 64        // S0 = k0 ^ n065        // S1 = k1 ^ n166        // S2 = C167        // S3 = C068        // S4 = k0 ^ C069        // S5 = k1 ^ C170        $k0_n0 = $k0 ^ $n0;71        $k1_n1 = $k1 ^ $n1;72        $state->state[0] = $k0_n0;73        $state->state[1] = $k1_n1;74        $state->state[2] = SODIUM_COMPAT_AEGIS_C1;75        $state->state[3] = SODIUM_COMPAT_AEGIS_C0;76        $state->state[4] = $k0 ^ SODIUM_COMPAT_AEGIS_C0;77        $state->state[5] = $k1 ^ SODIUM_COMPAT_AEGIS_C1;78 79        // Repeat(4,80        //   Update(k0)81        //   Update(k1)82        //   Update(k0 ^ n0)83        //   Update(k1 ^ n1)84        // )85        for ($i = 0; $i < 4; ++$i) {86            $state->update($k0);87            $state->update($k1);88            $state->update($k0 ^ $n0);89            $state->update($k1 ^ $n1);90        }91        return $state;92    }93