Share internet connection to android phone

share_connection.sh

#!/bin/sh


[ $UID = "0" ] || {
    echo "Please run as root."
    exit
}

[ $1 == '--help' ] && {
    echo <<HERE
    To use this file, set 'USB Tether' on the phone first
HERE
    exit
}

my_ip="192.168.42.99"
my_interface="usb0"
my_output_interface="wlan0"
phone_ip="192.168.42.98"
phone_interface="usb0"
dns1="8.8.8.8"
dns2="8.8.4.4"



echo Turning interface on.
ifconfig $my_interface $my_ip up 2>/dev/null

echo Setting remote ip address.
adb shell ifconfig $phone_interface $phone_ip up 2>/dev/null

echo Removing old routing rules \(sharing\) on phone.
conn=`adb shell busybox ip route | grep $phone_interface | sed 's/ .*$//'`
echo conn | xargs -I9 adb shell busybox ip route del 9 2>/dev/null

echo Removing default rule on phone.
adb shell busybox ip route del default

echo Setting local route rules.
iptables -t nat -F
iptables -t nat -X
iptables -t nat -Z
ip ro | grep $my_interface | sed 's/ .*$//' | xargs -I9 ip ro del 9
ip ro add $phone_ip dev $my_interface
echo 1 > /proc/sys/net/ipv4/ip_forward
iptables -t nat -j MASQUERADE -A POSTROUTING -o $my_output_interface

echo Setting remove route rules.
adb shell busybox ip ro add default dev $phone_interface
adb shell busybox ip ro change default via $my_ip

echo Setting DNS server on phone.
adb shell setprop net.dns1 $dns1 2>/dev/null
adb shell setprop net.dns2 $dns2 2>/dev/null

echo Now I\'ll try to ping google, read the result.
adb shell busybox ping www.google.com 2>/dev/null

echo Done if passed the ping test.