Virtualbox setting 및 마스커테이딩 설정

1. Virtualbox setting
    - Permission setting
        vboxusers에 user 추가
    - Ethernet
        - Host I/F: masquerading bt TAP0
            GW: 192.168.10.1(TAP0's IP)
    - USB Host
        sudo vi /etc/init.d/mountdevsubfs.sh
            # Add following list into start().
            mkdir -p /dev/bus/usb/.usbfs
            domount usbfs "" /dev/bus/usb/.usbfs -obusmode=0700,devmode=0600,listmode=0644
            ln -s .usbfs/devices /dev/bus/usb/devices
            mount -rbind /dev/bus/usb /proc/bus/usb
        sudo vi /etc/fstab
            none    /procbus/usb    usbfs    devgid=<vboxusers GID>,devmod=0664    0 0

2. Virtual ethernet control and Masquerading
    sudo apt-get install uml-utilities

    - test on terminal
        sudo tunctl -u elechole -t tap0
        sudo iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE
        sudo iptables -L -t nat
        su -
        echo "1" > /proc/sys/net/ipv4/ip_forward
        ifconfig tap0 192.168.10.1 netmask 255.255.255.0
    - Auto-configuration on Boot process
        sudo vi /etc/network/interfaces
            auto tap0
            iface tap0 inet static
            address 192.168.10.1
            netmask 255.255.255.0
            tunctl_user elechole
        sudo vi /etc/rc.local or /etc/rc.d/rc.local
            echo "1" > /proc/sys/net/ipv4/ip_forward
            iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE