ParagonIE_Sodium_Core32_BLAKE2b::init( SplFixedArray|null $key = null, int $outlen = 64, SplFixedArray|null $salt = null, SplFixedArray|null $personal = null ): SplFixedArray

497    public static function init(498        $key = null,499        $outlen = 64,500        $salt = null,501        $personal = null502    ) {503        self::pseudoConstructor();504        $klen = 0;505 506        if ($key !== null) {507            if (count($key) > 64) {508                throw new SodiumException('Invalid key size');509            }510            $klen = count($key);511        }512 513        if ($outlen > 64) {514            throw new SodiumException('Invalid output size');515        }516 517        $ctx = self::context();518 519        $p = new SplFixedArray(64);520        // Zero our param buffer...521        for ($i = 64; --$i;) {522            $p[$i] = 0;523        }524 525        $p[0] = $outlen; // digest_length526        $p[1] = $klen;   // key_length527        $p[2] = 1;       // fanout528        $p[3] = 1;       // depth529 530        if ($salt instanceof SplFixedArray) {531            // salt: [32] through [47]532            for ($i = 0; $i < 16; ++$i) {533                $p[32 + $i] = (int) $salt[$i];534            }535        }536        if ($personal instanceof SplFixedArray) {537            // personal: [48] through [63]538            for ($i = 0; $i < 16; ++$i) {539                $p[48 + $i] = (int) $personal[$i];540            }541        }542 543        $ctx[0][0] = self::xor64(544            $ctx[0][0],545            self::load64($p, 0)546        );547 548        if ($salt instanceof SplFixedArray || $personal instanceof SplFixedArray) {549            // We need to do what blake2b_init_param() does:550            for ($i = 1; $i < 8; ++$i) {551                $ctx[0][$i] = self::xor64(552                    $ctx[0][$i],553                    self::load64($p, $i << 3)554                );555            }556        }557 558        if ($klen > 0 && $key instanceof SplFixedArray) {559            $block = new SplFixedArray(128);560            for ($i = 128; $i--;) {561                $block[$i] = 0;562            }563            for ($i = $klen; $i--;) {564                $block[$i] = $key[$i];565            }566            self::update($ctx, $block, 128);567            $ctx[4] = 128;568        }569 570        return $ctx;571    }