Sync

# Docker environment variabeles

: ${VM_NET_TAP:='qemu'}

: ${VM_NET_DEV:='eth0'}

: ${VM_NET_HOST:='QEMU'}

: ${VM_NET_MAC:='82:cf:d0:5e:57:66'}

configureDHCP() {

  # Create /dev/vhost-net

  if [ ! -c /dev/vhost-net ]; then

    mknod /dev/vhost-net c 10 238

    chmod 660 /dev/vhost-net

  fi

  VM_NET_VLAN="vlan"

  GATEWAY=$(ip r | grep default | awk '{print $3}')

  NETWORK=$(ip -o route | grep "${VM_NET_DEV}" | grep -v default | awk '{print $1}')

  IP=$(ip address show dev "${VM_NET_DEV}" | grep inet | awk '/inet / { print $2 }' | cut -f1 -d/)

  if [ ! -c /dev/vhost-net ]; then

    echo -n "Error: VHOST interface not available. Please add the following "

    echo "docker variable to your container: --device=/dev/vhost-net" && exit 85

  fi

  ip l add link "${VM_NET_DEV}" "${VM_NET_VLAN}" type macvlan mode bridge

  ip address add "${IP}" dev "${VM_NET_VLAN}"

  ip link set dev "${VM_NET_VLAN}" up

  ip route flush dev "${VM_NET_DEV}"

  ip route flush dev "${VM_NET_VLAN}"

  ip route add "${NETWORK}" dev "${VM_NET_VLAN}" metric 0

  ip route add default via "${GATEWAY}"

  VM_NET_TAP="qemu"

  echo "Info: Retrieving IP via DHCP using MAC ${VM_NET_MAC}..."

  ip l add link eth0 name "${VM_NET_TAP}" address "${VM_NET_MAC}" type macvtap mode bridge || true

  ip l add link "${VM_NET_DEV}" name "${VM_NET_TAP}" address "${VM_NET_MAC}" type macvtap mode bridge || true

  ip l set "${VM_NET_TAP}" up

  ip a flush eth0

  ip a flush "${VM_NET_DEV}"

  ip a flush "${VM_NET_TAP}"

  DHCP_IP=$( dhclient -v "${VM_NET_TAP}" 2>&1 | grep ^bound | cut -d' ' -f3 )

  ip a flush "${VM_NET_TAP}"

  TAP_PATH="/dev/tap$(</sys/class/net/${VM_NET_TAP}/ifindex)"

  # Create /dev/vhost-net

  if [ ! -c /dev/vhost-net ]; then

    mknod /dev/vhost-net c 10 238

    chmod 660 /dev/vhost-net

  fi

  if [ ! -c /dev/vhost-net ]; then

    echo -n "Error: VHOST interface not available. Please add the following "

    echo "docker variable to your container: --device=/dev/vhost-net" && exit 85

  fi

  TAP_NR=$(</sys/class/net/"${VM_NET_TAP}"/ifindex)

  TAP_PATH="/dev/tap${TAP_NR}"

  # Create dev file (there is no udev in container: need to be done manually)

  IFS=: read -r MAJOR MINOR < <(cat /sys/devices/virtual/net/"${VM_NET_TAP}"/tap*/dev)

configureNAT () {

  VM_NET_TAP="qemu"

  VM_NET_IP='20.20.20.21'

  #Create bridge with static IP for the VM guest

  brctl addbr dockerbridge

  ip addr add ${VM_NET_IP%.*}.1/24 broadcast ${VM_NET_IP%.*}.255 dev dockerbridge

  ip link set dockerbridge up

  #QEMU Works with taps, set tap to the bridge created

  ip tuntap add dev ${VM_NET_TAP} mode tap

  ip link set ${VM_NET_TAP} up promisc on

  brctl addif dockerbridge ${VM_NET_TAP}

  ip tuntap add dev "${VM_NET_TAP}" mode tap

  ip link set "${VM_NET_TAP}" up promisc on

  brctl addif dockerbridge "${VM_NET_TAP}"

  #Add internet connection to the VM

  iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE

  iptables -t nat -A PREROUTING -i eth0 -p tcp  -j DNAT --to $VM_NET_IP

  iptables -t nat -A PREROUTING -i eth0 -p udp  -j DNAT --to $VM_NET_IP

  iptables -t nat -A POSTROUTING -o "${VM_NET_DEV}" -j MASQUERADE

  iptables -t nat -A PREROUTING -i "${VM_NET_DEV}" -p tcp  -j DNAT --to $VM_NET_IP

  iptables -t nat -A PREROUTING -i "${VM_NET_DEV}" -p udp  -j DNAT --to $VM_NET_IP

  # Hack for guest VMs complaining about "bad udp checksums in 5 packets"

  iptables -A POSTROUTING -t mangle -p udp --dport bootpc -j CHECKSUM --checksum-fill

  iptables -A POSTROUTING -t mangle -p udp --dport bootpc -j CHECKSUM --checksum-fill || true

  #Enable port forwarding flag

  [[ $(< /proc/sys/net/ipv4/ip_forward) -eq 0 ]] && sysctl -w net.ipv4.ip_forward=1

if [ "$DEBUG" = "Y" ]; then

  IP=$(ip address show dev eth0 | grep inet | awk '/inet / { print $2 }' | cut -f1 -d/)

  IP=$(ip address show dev "${VM_NET_DEV}" | grep inet | awk '/inet / { print $2 }' | cut -f1 -d/)

  echo "Info: Container IP is ${IP} with gateway ${GATEWAY}"

fi