ParagonIE_Sodium_Core32_Poly1305_State::__construct( string $key = '' )

52    public function __construct($key = '')53    {54        if (self::strlen($key) < 32) {55            throw new InvalidArgumentException(56                'Poly1305 requires a 32-byte key'57            );58        }59        /* r &= 0xffffffc0ffffffc0ffffffc0fffffff */60        $this->r = array(61            // st->r[0] = ...62            ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($key, 0, 4))63                ->setUnsignedInt(true)64                ->mask(0x3ffffff),65            // st->r[1] = ...66            ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($key, 3, 4))67                ->setUnsignedInt(true)68                ->shiftRight(2)69                ->mask(0x3ffff03),70            // st->r[2] = ...71            ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($key, 6, 4))72                ->setUnsignedInt(true)73                ->shiftRight(4)74                ->mask(0x3ffc0ff),75            // st->r[3] = ...76            ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($key, 9, 4))77                ->setUnsignedInt(true)78                ->shiftRight(6)79                ->mask(0x3f03fff),80            // st->r[4] = ...81            ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($key, 12, 4))82                ->setUnsignedInt(true)83                ->shiftRight(8)84                ->mask(0x00fffff)85        );86 87        /* h = 0 */88        $this->h = array(89            new ParagonIE_Sodium_Core32_Int32(array(0, 0), true),90            new ParagonIE_Sodium_Core32_Int32(array(0, 0), true),91            new ParagonIE_Sodium_Core32_Int32(array(0, 0), true),92            new ParagonIE_Sodium_Core32_Int32(array(0, 0), true),93            new ParagonIE_Sodium_Core32_Int32(array(0, 0), true)94        );95 96        /* save pad for later */97        $this->pad = array(98            ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($key, 16, 4))99                ->setUnsignedInt(true)->toInt64(),100            ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($key, 20, 4))101                ->setUnsignedInt(true)->toInt64(),102            ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($key, 24, 4))103                ->setUnsignedInt(true)->toInt64(),104            ParagonIE_Sodium_Core32_Int32::fromReverseString(self::substr($key, 28, 4))105                ->setUnsignedInt(true)->toInt64(),106        );107 108        $this->leftover = 0;109        $this->final = false;110    }