ParagonIE_Sodium_Core_AES::doubleRound( string $b0, string $rk0, string $b1, string $rk1 ): string[]

457    public static function doubleRound($b0, $rk0, $b1, $rk1)458    {459        $q = ParagonIE_Sodium_Core_AES_Block::init();460        // First block461        $q[0] = self::load_4(self::substr($b0, 0, 4));462        $q[2] = self::load_4(self::substr($b0, 4, 4));463        $q[4] = self::load_4(self::substr($b0, 8, 4));464        $q[6] = self::load_4(self::substr($b0, 12, 4));465        // Second block466        $q[1] = self::load_4(self::substr($b1, 0, 4));467        $q[3] = self::load_4(self::substr($b1, 4, 4));468        $q[5] = self::load_4(self::substr($b1, 8, 4));469        $q[7] = self::load_4(self::substr($b1, 12, 4));;470 471        $rk = ParagonIE_Sodium_Core_AES_Block::init();472        // First round key473        $rk[0] = self::load_4(self::substr($rk0, 0, 4));474        $rk[2] = self::load_4(self::substr($rk0, 4, 4));475        $rk[4] = self::load_4(self::substr($rk0, 8, 4));476        $rk[6] = self::load_4(self::substr($rk0, 12, 4));477        // Second round key478        $rk[1] = self::load_4(self::substr($rk1, 0, 4));479        $rk[3] = self::load_4(self::substr($rk1, 4, 4));480        $rk[5] = self::load_4(self::substr($rk1, 8, 4));481        $rk[7] = self::load_4(self::substr($rk1, 12, 4));482 483        $q->orthogonalize();484        self::sbox($q);485        $q->shiftRows();486        $q->mixColumns();487        $q->orthogonalize();488        // add round key without key schedule:489        for ($i = 0; $i < 8; ++$i) {490            $q[$i] ^= $rk[$i];491        }492        return array(493            self::store32_le($q[0]) . self::store32_le($q[2]) . self::store32_le($q[4]) . self::store32_le($q[6]),494            self::store32_le($q[1]) . self::store32_le($q[3]) . self::store32_le($q[5]) . self::store32_le($q[7]),495        );496    }