1#!/bin/bash 2# 3# QEMU network interface configuration script. This utility needs to 4# be run as root, and will use the tunctl binary from a native sysroot. 5# Note: many Linux distros these days still use an older version of 6# tunctl which does not support the group permissions option, hence 7# the need to use build system's version. 8# 9# If you find yourself calling this script a lot, you can add the 10# the following to your /etc/sudoers file to be able to run this 11# command without entering your password each time: 12# 13# <my-username> ALL=NOPASSWD: /path/to/runqemu-ifup 14# <my-username> ALL=NOPASSWD: /path/to/runqemu-ifdown 15# 16# If you'd like to create a bank of tap devices at once, you should use 17# the runqemu-gen-tapdevs script instead. If tap devices are set up using 18# that script, the runqemu script will never end up calling this 19# script. 20# 21# Copyright (c) 2006-2011 Linux Foundation 22# 23# SPDX-License-Identifier: GPL-2.0-only 24# 25 26usage() { 27 echo "sudo $(basename $0) <uid> <gid> <native-sysroot-basedir>" 28} 29 30if [ $EUID -ne 0 ]; then 31 echo "Error: This script (runqemu-ifup) must be run with root privileges" 32 exit 1 33fi 34 35if [ $# -ne 3 ]; then 36 usage 37 exit 1 38fi 39 40USERID="-u $1" 41GROUP="-g $2" 42STAGING_BINDIR_NATIVE=$3 43 44TUNCTL=$STAGING_BINDIR_NATIVE/tunctl 45if [ ! -x "$TUNCTL" ]; then 46 echo "Error: Unable to find tunctl binary in '$STAGING_BINDIR_NATIVE', please bitbake qemu-helper-native" 47 exit 1 48fi 49 50TAP=`$TUNCTL -b $GROUP 2>&1` 51STATUS=$? 52if [ $STATUS -ne 0 ]; then 53# If tunctl -g fails, try using tunctl -u, for older host kernels 54# which do not support the TUNSETGROUP ioctl 55 TAP=`$TUNCTL -b $USERID 2>&1` 56 STATUS=$? 57 if [ $STATUS -ne 0 ]; then 58 echo "tunctl failed:" 59 exit 1 60 fi 61fi 62 63IFCONFIG=`which ip 2> /dev/null` 64if [ "x$IFCONFIG" = "x" ]; then 65 # better than nothing... 66 IFCONFIG=/sbin/ip 67fi 68if [ ! -x "$IFCONFIG" ]; then 69 echo "$IFCONFIG cannot be executed" 70 exit 1 71fi 72 73IPTABLES=`which iptables 2> /dev/null` 74if [ "x$IPTABLES" = "x" ]; then 75 IPTABLES=/sbin/iptables 76fi 77if [ ! -x "$IPTABLES" ]; then 78 echo "$IPTABLES cannot be executed" 79 exit 1 80fi 81 82n=$[ (`echo $TAP | sed 's/tap//'` * 2) + 1 ] 83$IFCONFIG addr add 192.168.7.$n/32 broadcast 192.168.7.255 dev $TAP 84STATUS=$? 85if [ $STATUS -ne 0 ]; then 86 echo "Failed to set up IP addressing on $TAP" 87 exit 1 88fi 89$IFCONFIG link set dev $TAP up 90STATUS=$? 91if [ $STATUS -ne 0 ]; then 92 echo "Failed to bring up $TAP" 93 exit 1 94fi 95 96dest=$[ (`echo $TAP | sed 's/tap//'` * 2) + 2 ] 97$IFCONFIG route add to 192.168.7.$dest dev $TAP 98STATUS=$? 99if [ $STATUS -ne 0 ]; then 100 echo "Failed to add route to 192.168.7.$dest using $TAP" 101 exit 1 102fi 103 104# setup NAT for tap0 interface to have internet access in QEMU 105$IPTABLES -A POSTROUTING -t nat -j MASQUERADE -s 192.168.7.$n/32 106$IPTABLES -A POSTROUTING -t nat -j MASQUERADE -s 192.168.7.$dest/32 107echo 1 > /proc/sys/net/ipv4/ip_forward 108echo 1 > /proc/sys/net/ipv4/conf/$TAP/proxy_arp 109$IPTABLES -P FORWARD ACCEPT 110 111echo $TAP 112