#!/bin/bash # # QEMU network interface configuration script. This utility needs to # be run as root, and will use the tunctl binary from a native sysroot. # Note: many Linux distros these days still use an older version of # tunctl which does not support the group permissions option, hence # the need to use build system's version. # # If you find yourself calling this script a lot, you can add the # the following to your /etc/sudoers file to be able to run this # command without entering your password each time: # # ALL=NOPASSWD: /path/to/runqemu-ifup # ALL=NOPASSWD: /path/to/runqemu-ifdown # # If you'd like to create a bank of tap devices at once, you should use # the runqemu-gen-tapdevs script instead. If tap devices are set up using # that script, the runqemu script will never end up calling this # script. # # Copyright (c) 2006-2011 Linux Foundation # # This program is free software; you can redistribute it and/or modify # it under the terms of the GNU General Public License version 2 as # published by the Free Software Foundation. # # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License along # with this program; if not, write to the Free Software Foundation, Inc., # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. usage() { echo "sudo $(basename $0) " } if [ $EUID -ne 0 ]; then echo "Error: This script (runqemu-ifup) must be run with root privileges" exit 1 fi if [ $# -ne 2 ]; then usage exit 1 fi GROUP="-g $1" NATIVE_SYSROOT_DIR=$2 TUNCTL=$NATIVE_SYSROOT_DIR/usr/bin/tunctl if [ ! -x "$TUNCTL" ]; then echo "Error: Unable to find tunctl binary in '$NATIVE_SYSROOT_DIR/usr/bin'" exit 1 fi TAP=`$TUNCTL -b $GROUP 2>&1` STATUS=$? if [ $STATUS -ne 0 ]; then echo "tunctl failed:" echo $TAP exit 1 fi IFCONFIG=`which ifconfig 2> /dev/null` if [ "x$IFCONFIG" = "x" ]; then # better than nothing... IFCONFIG=/sbin/ifconfig fi ROUTE=`which route` if [ "x$ROUTE" = "x" ]; then # better than nothing... ROUTE=/sbin/route fi n=$[ (`echo $TAP | sed 's/tap//'` * 2) + 1 ] $IFCONFIG $TAP 192.168.7.$n dest=$[ (`echo $TAP | sed 's/tap//'` * 2) + 2 ] $ROUTE add -host 192.168.7.$dest $TAP # setup NAT for tap0 interface to have internet access in QEMU IPTABLES=`which iptables` if [ "x$IPTABLES" = "x" ]; then IPTABLES=/sbin/iptables fi $IPTABLES -A POSTROUTING -t nat -j MASQUERADE -s 192.168.7.0/24 echo 1 > /proc/sys/net/ipv4/ip_forward $IPTABLES -P FORWARD ACCEPT echo $TAP