phpseclib\Crypt\Blowfish::_setupKey PHP Метод

    function _setupKey()
    {
        if (isset($this->kl['key']) && $this->key === $this->kl['key']) {
            // already expanded
            return;
        }
        $this->kl = array('key' => $this->key);
        /* key-expanding p[] and S-Box building sb[] */
        $this->bctx = array('p' => array(), 'sb' => array($this->sbox0, $this->sbox1, $this->sbox2, $this->sbox3));
        // unpack binary string in unsigned chars
        $key = array_values(unpack('C*', $this->key));
        $keyl = count($key);
        for ($j = 0, $i = 0; $i < 18; ++$i) {
            // xor P1 with the first 32-bits of the key, xor P2 with the second 32-bits ...
            for ($data = 0, $k = 0; $k < 4; ++$k) {
                $data = $data << 8 | $key[$j];
                if (++$j >= $keyl) {
                    $j = 0;
                }
            }
            $this->bctx['p'][] = $this->parray[$i] ^ $data;
        }
        // encrypt the zero-string, replace P1 and P2 with the encrypted data,
        // encrypt P3 and P4 with the new P1 and P2, do it with all P-array and subkeys
        $data = "";
        for ($i = 0; $i < 18; $i += 2) {
            list($l, $r) = array_values(unpack('N*', $data = $this->_encryptBlock($data)));
            $this->bctx['p'][$i] = $l;
            $this->bctx['p'][$i + 1] = $r;
        }
        for ($i = 0; $i < 4; ++$i) {
            for ($j = 0; $j < 256; $j += 2) {
                list($l, $r) = array_values(unpack('N*', $data = $this->_encryptBlock($data)));
                $this->bctx['sb'][$i][$j] = $l;
                $this->bctx['sb'][$i][$j + 1] = $r;
            }
        }
    }