From 06118fca12f819f575d8ab42969ed3ea4519efec Mon Sep 17 00:00:00 2001
From: Kroese <kroese@users.noreply.github.com>
Date: Sun, 9 Apr 2023 16:15:26 +0200
Subject: [PATCH] Simplify network code

---
 network.sh | 50 ++++++--------------------------------------------
 1 file changed, 6 insertions(+), 44 deletions(-)

diff --git a/network.sh b/network.sh
index 920f446..0cc112b 100644
--- a/network.sh
+++ b/network.sh
@@ -1,50 +1,25 @@
 #!/usr/bin/env bash
 set -eu
 
-: ${INFO:='N'}
-: ${DEBUG:='N'}
+: ${VM_NET_TAP:=''}
+: ${VM_NET_IP:='20.20.20.21'}
+: ${VM_NET_MAC:='00:11:32:2C:A7:85'}
 
 : ${DNSMASQ:='/usr/sbin/dnsmasq'}
 : ${DNSMASQ_OPTS:=''}
 : ${DNSMASQ_CONF_DIR:='/etc/dnsmasq.d'}
 : ${DNS_SERVERS:=''}
 
-: ${VM_NET_TAP:=''}
-: ${VM_NET_IP:='20.20.20.21'}
-: ${VM_NET_MAC:='00:11:32:2C:A7:85'}
-
 # ######################################
 #  Functions
 # ######################################
 
-log () {
-  case "$1" in
-    WARNING | ERROR )
-      echo "$1: ${@:2}"
-      ;;
-    INFO)
-      if [[ "$INFO" == [Yy1]* ]]; then
-          echo "$1: ${@:2}"
-      fi
-      ;;
-    DEBUG)
-      if [[ "$DEBUG" == [Yy1]* ]]; then
-          echo "$1: ${@:2}"
-      fi
-      ;;
-    *)
-      echo "-- $@"
-      ;;
-  esac
-}
-
 setupLocalDhcp () {
   CIDR="24"
   MAC="$1"
   IP="$2"
   HOSTNAME="VirtualDSM"
   # dnsmasq configuration:
-  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
   echo "0 $MAC $IP $HOSTNAME 01:${MAC}" > /var/lib/misc/dnsmasq.leases
@@ -55,8 +30,7 @@ setupLocalDhcp () {
 # to connect the host machine to the network
 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 
   brctl addbr dockerbridge
   ip addr add ${VM_NET_IP%.*}.1/24 broadcast ${VM_NET_IP%.*}.255 dev dockerbridge
   ip link set dockerbridge up
@@ -73,7 +47,6 @@ configureNatNetworks () {
   #Enable port forwarding flag
   [[ $(< /proc/sys/net/ipv4/ip_forward) -eq 0 ]] && sysctl -w net.ipv4.ip_forward=1
 
-  #For now we define static MAC because DHCP is very slow if DHCP change every VM Boot
   setupLocalDhcp $VM_NET_MAC $VM_NET_IP
 }
 
@@ -90,16 +63,10 @@ fi
 
 [ ! -c /dev/net/tun ] && echo "Error: TUN network interface not available..." && exit 85
 
-#log "INFO" "Little dirty trick ..."
 update-alternatives --set iptables /usr/sbin/iptables-legacy > /dev/null
 update-alternatives --set ip6tables /usr/sbin/ip6tables-legacy > /dev/null
 
-log "INFO" "Configuring network ..."
-#DEFAULT_ROUTE=$(ip route | grep default | awk '{print $3}')
-
 VM_NET_TAP="_VmNatTap"
-log "INFO" "... NAT Network (${VM_NET_TAP}) to ${VM_NET_IP}"
-
 configureNatNetworks
 KVM_NET_OPTS="-netdev tap,ifname=${VM_NET_TAP},script=no,downscript=no,id=hostnet0"
 
@@ -110,7 +77,7 @@ domainname=$(echo $searchdomains | awk -F"," '{print $1}')
 
 for nameserver in "${nameservers[@]}"; do
   if [[ $nameserver =~ .*:.* ]]; then
-    log "INFO" "Skipping IPv6 nameserver: $nameserver"
+    echo "Skipping IPv6 nameserver: $nameserver"
   else
     [[ -z $DNS_SERVERS ]] && DNS_SERVERS=$nameserver || DNS_SERVERS="$DNS_SERVERS,$nameserver"
   fi
@@ -124,14 +91,9 @@ DNSMASQ_OPTS="$DNSMASQ_OPTS \
 
 [[ -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
 	
 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"
-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 )
-
-log "INFO" "Done setting up network.."
+iptables -A POSTROUTING -t mangle -p udp --dport bootpc -j CHECKSUM --checksum-fill