From 04d0635b80eec4496d908221f7943a421c61b077 Mon Sep 17 00:00:00 2001
From: Kroese <kroese@users.noreply.github.com>
Date: Sun, 9 Apr 2023 16:02:06 +0200
Subject: [PATCH] Simplify network code

---
 network.sh | 115 ++++++++++++++---------------------------------------
 1 file changed, 29 insertions(+), 86 deletions(-)

diff --git a/network.sh b/network.sh
index d120cdc..920f446 100644
--- a/network.sh
+++ b/network.sh
@@ -9,14 +9,9 @@ set -eu
 : ${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
@@ -47,12 +42,11 @@ setupLocalDhcp () {
   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
 }
@@ -62,7 +56,7 @@ setupLocalDhcp () {
 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
@@ -87,9 +81,6 @@ configureNatNetworks () {
 #  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
@@ -106,89 +97,41 @@ update-alternatives --set ip6tables /usr/sbin/ip6tables-legacy > /dev/null
 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: ${VM_NET_MAC}"
+VM_NET_TAP="_VmNatTap"
+log "INFO" "... NAT Network (${VM_NET_TAP}) to ${VM_NET_IP}"
 
-		ip l add link eth0 name ${VM_NET_TAP} address ${VM_NET_MAC} type macvtap mode bridge || true
-		ip l set ${VM_NET_TAP} up
+configureNatNetworks
+KVM_NET_OPTS="-netdev tap,ifname=${VM_NET_TAP},script=no,downscript=no,id=hostnet0"
 
-		ip a flush eth0
-		ip a flush ${VM_NET_TAP}
+# Build DNS options from container /etc/resolv.conf
+nameservers=($(grep '^nameserver' /etc/resolv.conf | sed 's/nameserver //'))
+searchdomains=$(grep '^search' /etc/resolv.conf | sed 's/search //' | sed 's/ /,/g')
+domainname=$(echo $searchdomains | awk -F"," '{print $1}')
 
-		_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: ${VM_NET_MAC}" && exit 16 )
+for nameserver in "${nameservers[@]}"; do
+  if [[ $nameserver =~ .*:.* ]]; then
+    log "INFO" "Skipping IPv6 nameserver: $nameserver"
+  else
+    [[ -z $DNS_SERVERS ]] && DNS_SERVERS=$nameserver || DNS_SERVERS="$DNS_SERVERS,$nameserver"
+  fi
+done
 
-		ip a flush ${VM_NET_TAP}
+DNSMASQ_OPTS="$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"
 
-		_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"
+[[ -z $(hostname -d) ]] || DNSMASQ_OPTS="$DNSMASQ_OPTS --dhcp-option=option:domain-name,$(hostname -d)"
 
-		[[ "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 ${VM_NET_IP}"
-
-		configureNatNetworks
-		KVM_NET_OPTS="-netdev tap,ifname=${VM_NET_TAP},script=no,downscript=no,id=hostnet0"
-
-		# Build DNS options from container /etc/resolv.conf
-		nameservers=($(grep '^nameserver' /etc/resolv.conf | sed 's/nameserver //'))
-		searchdomains=$(grep '^search' /etc/resolv.conf | sed 's/search //' | sed 's/ /,/g')
-		domainname=$(echo $searchdomains | awk -F"," '{print $1}')
-
-		for nameserver in "${nameservers[@]}"; do
-		  if [[ $nameserver =~ .*:.* ]]; then
-		    log "INFO" "Skipping IPv6 nameserver: $nameserver"
-		  else
-		    [[ -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      \
-		  "
-		[[ -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"
+log "INFO" "... Lauching dnsmasq"
+log "DEBUG" "dnsmasq options: $DNSMASQ_OPTS"
+$DNSMASQ $DNSMASQ_OPTS
+	
+KVM_NET_OPTS="${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.."