# virtual machine under QEMU, This script allows the host box
# to share its network connection with qemu-based guests
#
-# Author: Amine chaoui
-#
COMMAND=$(basename $0)
cd $(dirname $0)
# constant
INTERFACE_BRIDGE=br0
-# Default Value
-INTERFACE_LAN=eth0
+#################### compute INTERFACE_LAN
+# use /proc/net/dev instead of a hard-wired list
+function gather_interfaces () {
+ python <<EOF
+for line in file("/proc/net/dev"):
+ if ':' not in line: continue
+ ifname=line.replace(" ","").split(":")[0]
+ if ifname.find("lo")==0: continue
+ if ifname.find("br")==0: continue
+ if ifname.find("virbr")==0: continue
+ if ifname.find("tap")==0: continue
+ print ifname
+EOF
+}
+
+function discover_interface () {
+ for ifname in $(gather_interfaces); do
+ ip link show $ifname | grep -qi 'state UP' && { echo $ifname; return; }
+ done
+ # still not found ? that's bad
+ echo unknown
+}
+INTERFACE_LAN=$(discover_interface)
+echo Using physical interface $INTERFACE_LAN
+
+####################
# Fonction de mise en place du pont
-start () {
+function start () {
echo "========== $COMMAND: entering start - beg"
hostname
netstat -rn
echo "========== $COMMAND: entering start - end"
-# -A FORWARD -m physdev --physdev-is-bridged -j ACCEPT
+ # disable netfilter calls for bridge interface (they cause panick on 2.6.35 anyway)
+ #
+ # another option would be to accept the all forward packages for
+ # bridged interface like: -A FORWARD -m physdev --physdev-is-bridged -j ACCEPT
+ sysctl net.bridge.bridge-nf-call-iptables=0
+ sysctl net.bridge.bridge-nf-call-ip6tables=0
+ sysctl net.bridge.bridge-nf-call-arptables=0
# take extra arg for ifname, if provided
[ -n "$1" ] && { INTERFACE_LAN=$1; shift ; }
}
#Adding a new interface to the bridge: this is used by qemu-ifup
-add () {
+function add () {
[[ -z "$@" ]] && { echo "Usage: $COMMAND add ifname" ; exit 1 ; }
INTERFACE_LAN=$1; shift
}
#Stop the bridge and restore the original setting
-stop () {
+function stop () {
# take extra arg for ifname, if provided
[ -n "$1" ] && { INTERFACE_LAN=$1; shift ; }