= Replicant USB Networking =

This page explains how to connect your Replciant phone to the Internet via an USB connection to a computer connected to the Internet. 

== What you need ==

* A phone running Replicant
* A computer with USB connectivity and network access running GNU/Linux

== Automation scripts ==

Two scripts are necessary: one to run on the host computer and one to run on the device.

=== Replicant USB Networking - PC ===

Here's the script to run on the computer. Copy the following text to a file named "run_pc.sh" (or any other name, you just need to keep the same name along the process):

{{{
#!/bin/sh

# Replicant USB Networking
# ========================                             
# 
# Copyright (C) 2010 Paul Kocialkowski, GPLv3+
# 
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
# 
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

IPTABLES_CLEAN_RULES=true

USB_IFACE="usb0"
INTERNET_IFACE="eth0"

USB_IFACE_IP="192.168.4.200"

# Clean iptables rules

iptables_rules_clean () {
	if [ $IPTABLES_CLEAN_RULES = false ]
	then
		return
	fi

	iptables --flush
	iptables --table nat --flush
	iptables --delete-chain
	iptables --table nat --delete-chain
}

# Inject iptables forwarding rules

iptables_forward_rules_apply () {
	iptables --table nat --append POSTROUTING --out-interface $INTERNET_IFACE -j MASQUERADE
	iptables --append FORWARD --in-interface $USB_IFACE -j ACCEPT
	echo 1 > /proc/sys/net/ipv4/ip_forward 
}

# Configure network link

usb_networking_configure () {
	ifconfig $USB_IFACE up
	ifconfig $USB_IFACE $USB_IFACE_IP
}

usb_networking_disable () {
	ifconfig $USB_IFACE down
	echo 0 > /proc/sys/net/ipv4/ip_forward 
}

case $1 in
	"start")
		echo "Starting Replicant USB Networking"
		iptables_rules_clean
		usb_networking_configure
		iptables_forward_rules_apply
	;;
	"stop")
		echo "Stopping Replicant USB Networking"
		usb_networking_disable
		iptables_rules_clean
	;;
	*)#!/bin/sh

# Replicant USB Networking
# ========================                             
# 
# Copyright (C) 2010 Paul Kocialkowski, GPLv3+
# 
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
# 
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

IPTABLES_CLEAN_RULES=true

USB_IFACE="usb0"
INTERNET_IFACE="eth0"

USB_IFACE_IP="192.168.4.200"

# Clean iptables rules

iptables_rules_clean () {
	if [ $IPTABLES_CLEAN_RULES = false ]
	then
		return
	fi

	iptables --flush
	iptables --table nat --flush
	iptables --delete-chain
	iptables --table nat --delete-chain
}

# Inject iptables forwarding rules

iptables_forward_rules_apply () {
	iptables --table nat --append POSTROUTING --out-interface $INTERNET_IFACE -j MASQUERADE
	iptables --append FORWARD --in-interface $USB_IFACE -j ACCEPT
	echo 1 > /proc/sys/net/ipv4/ip_forward 
}

# Configure network link

usb_networking_configure () {
	ifconfig $USB_IFACE up
	ifconfig $USB_IFACE $USB_IFACE_IP
}

usb_networking_disable () {
	ifconfig $USB_IFACE down
	echo 0 > /proc/sys/net/ipv4/ip_forward 
}

case $1 in
	"start")
		echo "Starting Replicant USB Networking"
		iptables_rules_clean
		usb_networking_configure
		iptables_forward_rules_apply
	;;
	"stop")
		echo "Stopping Replicant USB Networking"
		usb_networking_disable
		iptables_rules_clean
	;;
	*)
		echo "Usage: sh $0 {start|stop}"
	;;
esac
		echo "Usage: sh $0 {start|stop}"
	;;
esac
}}}

Then, set this file executable: 
{{{ chmod a+x run_pc.sh }}}

=== Replicant USB Networking - Device ===

Here's the script to run on the device. Copy the following text to a file named "run_dev.sh" (or any other name, you just need to keep the same name along the process):

{{{
#!/system/bin/sh

# Replicant USB Networking
# ========================                             
# 
# Copyright (C) 2010 Paul Kocialkowski, GPLv3+
# 
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
# 
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

# Enable USB Networking

USB_IFACE="usb0"

USB_IFACE_IP="192.168.4.202"
GATEWAY_IP="192.168.4.200"
DNS1_IP="8.8.8.8"

usb_networking_enable () {
	echo 1 > /sys/class/usb_composite/rndis/enable
	ifconfig usb0 up
}

usb_networking_configure () {
	ifconfig $USB_IFACE $USB_IFACE_IP
	route add default gw $GATEWAY_IP dev $USB_IFACE
	setprop net.dns1 $DNS1_IP

	# setprop net.dns1 $( cat /system/etc/resolv.conf | sed -e "s|.*#.*||" -e "s|^.*nameserver \(.*\)$|\1|g" | grep -v "^$" | head -n 1 )
}

usb_networking_disable () {
	echo 0 > /sys/class/usb_composite/rndis/enable
	ifconfig usb0 down
}

case $1 in
	"start")
		echo "Starting Replicant USB Networking"
		usb_networking_enable
		usb_networking_configure
	;;
	"stop")
		echo "Stopping Replicant USB Networking"
		usb_networking_disable
	;;
	*)
		echo "Usage: sh $0 {start|stop}"
	;;
esac
}}}

Now you need to copy it to your phone. Start adb server as root: {{{ # adb start-server }} and copy the file (as regular user): {{{ adb push run_dev.sh /sdcard/ }}} (you can change /sdcard/ to any other writable disk place, just remind where you put it).