Simplify network code

: ${DNSMASQ_CONF_DIR:='/etc/dnsmasq.d'}

: ${DNS_SERVERS:=''}

# # (VM_NET_IP: Dont need to change coz all is port forwarded)

# # (VM_NET_DHCP: It use MACVTAP which is not compatible with all configuration)

: ${VM_NET_TAP:=''}

: ${VM_NET_IP:='20.20.20.21'}

: ${VM_NET_MAC:='00:11:32:2C:A7:85'}

: ${VM_NET_DHCP:='N'}

: ${VM_ENABLE_VIRTIO:='Y'}

# ######################################

#  Functions

  CIDR="24"

  MAC="$1"

  IP="$2"

  #HOSTNAME=$(hostname -s)

  HOSTNAME="VirtualDSM"

  # dnsmasq configuration:

  log "INFO" "DHCP configured to serve IP $IP/$CIDR via dockerbridge"

  log "DEBUG" "DHCP configured to serve IP $IP/$CIDR via dockerbridge"

  DNSMASQ_OPTS="$DNSMASQ_OPTS --dhcp-range=$IP,$IP --dhcp-host=$MAC,,$IP,$HOSTNAME,infinite --dhcp-option=option:netmask,255.255.255.0"

  # Create lease File FOr faster resolve

  # Create lease file for faster resolve

  echo "0 $MAC $IP $HOSTNAME 01:${MAC}" > /var/lib/misc/dnsmasq.leases

  chmod 644 /var/lib/misc/dnsmasq.leases

}

configureNatNetworks () {

  #For now we define static MAC because DHCP is very slow if MAC change every VM Boot

  #Create bridge with static IP for the VM Guest(COnnection VM-Docker)

  #Create bridge with static IP for the VM Guest (Connection VM-Docker)

  brctl addbr dockerbridge

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

  ip link set dockerbridge up

#  Configure Network

# ######################################

MAJOR=""

_DhcpIP=""

# Create the necessary file structure for /dev/net/tun

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

  [ ! -d /dev/net ] && mkdir -m 755 /dev/net

log "INFO" "Configuring network ..."

#DEFAULT_ROUTE=$(ip route | grep default | awk '{print $3}')

if [[ "x${VM_NET_TAP}" == "x" ]]; then

	if [[ "${VM_NET_DHCP}" == [Yy1]* ]]; then

		VM_NET_TAP="_VmMacvtap"

		log "INFO" "... to retrieve IP via DHCP through Macvtap (${VM_NET_TAP}) and MAC: ${VM_NET_MAC}"

		ip l add link eth0 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_TAP}

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

		[[ "${_DhcpIP}" == [0-9.]* ]] \

		&& log "INFO" "... Retrieve IP: ${_DhcpIP} from DHCP with MAC: ${VM_NET_MAC}" \

		|| ( log "ERROR" "... Cannot retrieve IP from DHCP with MAC: ${VM_NET_MAC}" && exit 16 )

		ip a flush ${VM_NET_TAP}

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

		# get MAJOR MINOR DEVNAME

		MAJOR=""

		eval "$(</sys/class/net/${VM_NET_TAP}/macvtap/${_tmpTapPath##*/}/uevent) _tmp=0"

		[[ "x${MAJOR}" != "x" ]] \

			&& log "INFO" "... PLEASE MAKE SURE, Docker run command line used: --device-cgroup-rule='c ${MAJOR}:* rwm'" \

			|| ( log "ERROR" "... macvtap creation issue: Cannot find: /sys/class/net/${VM_NET_TAP}/" && exit 18 )

		[[ ! -e ${_tmpTapPath} ]] && [[ -e /dev0/${_tmpTapPath##*/} ]] && ln -s /dev0/${_tmpTapPath##*/} ${_tmpTapPath}

		if [[ ! -e ${_tmpTapPath} ]]; then

			log "WARNING" "... file does not exist: ${_tmpTapPath}"

			mknod ${_tmpTapPath} c $MAJOR $MINOR \

				&& log "INFO" "... File created with mknod: ${_tmpTapPath}" \

				|| ( log "ERROR" "... Cannot mknod: ${_tmpTapPath}" && exit 20 )

		fi

		KVM_NET_OPTS="-netdev tap,id=hostnet0,vhost=on,vhostfd=40,fd=30 30<>${_tmpTapPath} 40<>/dev/vhost-net"

	else

VM_NET_TAP="_VmNatTap"

log "INFO" "... NAT Network (${VM_NET_TAP}) to ${VM_NET_IP}"

    [[ -z $DNS_SERVERS ]] && DNS_SERVERS=$nameserver || DNS_SERVERS="$DNS_SERVERS,$nameserver"

  fi

done

DNSMASQ_OPTS="$DNSMASQ_OPTS \

  --dhcp-option=option:dns-server,$DNS_SERVERS \

  --dhcp-option=option:router,${VM_NET_IP%.*}.1 \

  --dhcp-option=option:domain-search,$searchdomains \

		  --dhcp-option=option:domain-name,$domainname      \

		  "

  --dhcp-option=option:domain-name,$domainname"

[[ -z $(hostname -d) ]] || DNSMASQ_OPTS="$DNSMASQ_OPTS --dhcp-option=option:domain-name,$(hostname -d)"

log "INFO" "... Lauching dnsmasq"

log "DEBUG" "dnsmasq options: $DNSMASQ_OPTS"

$DNSMASQ $DNSMASQ_OPTS

	fi

else

	log "INFO" "... No configuration, just using tuntap : ${VM_NET_TAP}"

	KVM_NET_OPTS="-netdev tap,ifname=${VM_NET_TAP},script=no,downscript=no,id=hostnet0"

fi

#KVM_NET_OPTS="-netdev user,hostfwd=tcp:127.0.0.1:5000-:5000"

[[ "${VM_ENABLE_VIRTIO}" == [Yy1]* ]] \

	&& KVM_NET_OPTS="${KVM_NET_OPTS} -device virtio-net-pci,netdev=hostnet0,mac=${VM_NET_MAC},id=net0" \

	|| KVM_NET_OPTS="${KVM_NET_OPTS} -device e1000e,netdev=hostnet0,mac=${VM_NET_MAC},id=net0"

KVM_NET_OPTS="${KVM_NET_OPTS} -device virtio-net-pci,netdev=hostnet0,mac=${VM_NET_MAC},id=net0" 

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

log "INFO" "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 \

        || ( log "WARNING" "Iptables hack for checksum FAILED" && ethtool -K eth0 tx off || true )

[[ "x${MAJOR}" != "x" ]] && log "INFO" "PLEASE MAKE SURE, Docker is using the following option otherwise you may have permission issue on ${_tmpTapPath} file: --device-cgroup-rule='c ${MAJOR}:* rwm' "

[[ "${_DhcpIP}" == [0-9.]* ]] && log "INFO" "You should access your DSM with: http://${_DhcpIP}:5000"

log "INFO" "Done setting up network.."