create_dual_ovpn_ddwrt.sh v1.1.0

#!/bin/sh
#=======================================================
# create_dual_ovpn_ddwrt.sh  - v1.1.0
#=======================================================
# Changelog
#=======================================================
# v1.1.0 - 02/20/2012 - Kain0o0
# - Changed name guessing to match new Strongvpn script
# - Created DUAL_SCRIPT variable for user preference
# - Created clean_sed function to parse sed output
# - Script is easily modified using clean_sed input
# - Modified code and added comments for easier reading
# - Added brakets for notepad++ collapsing support
# - Added changelog to track changes
# v1.0.2 - 08/12/2011 - Cfelix (Thanks!)
# - Added upnp line
# - Missing \'s for $RULE.  Changed to echo \\\\$\RULE
# - Modified various sed commands
# v1.0.1 - 11/29/2010 - Kain0o0
# - Added PORT_RANGE variable for easier modification
# v1.0.0 - 11/25/2010 - Kain0o0
# - initial release

# Modify if you have a different DHCP port range
# Script will route the ip's below through WAN
# You can use http://www.ipaddresslocation.org/subnet-mask-calculator.php to calculate ranges
# Please maintain format ip rule add from XXX.XXX.XXX.XXX\/XX lookup 4\n\

PORT_RANGE="\
ip rule add from 192.168.1.100/30 lookup 4
ip rule add from 192.168.1.104/29 lookup 4
ip rule add from 192.168.1.112/28 lookup 4
ip rule add from 192.168.1.128/25 lookup 4
"

# New script name, modify it if you have a naming preference
DUAL_SCRIPT="ovpn_dual_ddwrt.sh"

#BANNER
{
clear
echo
echo -e "\033[31m\033[47m=======================================================================\033[0m"
echo -e "\033[31m\033[47m                      CREATE_DUAL_OVPN_DDWRT                     v1.1.0\033[0m"
echo -e "\033[31m\033[47m                        www.obesevegan.com                             \033[0m"
echo -e "\033[31m\033[47m\a=======================================================================\033[0m"
echo -e "\033[30m\033[47m This script will reconfigure the openvpn installation script to route \033[0m"
echo -e "\033[30m\033[47m all non-dhcp ports (192.168.1.2 -> 192.168.1.99) through openvpn      \033[0m"
echo -e "\033[30m\033[47m DHCP ports will be sent through ISP.                                  \033[0m"
echo -e "\033[30m\033[47m                                                                       \033[0m"
echo -e "\033[34m\033[47m Input:  Original StrongVPN installer script (ovpnXXX_ddwrt_small.sh)  \033[0m"
echo -e "\033[34m\033[47m Output: Dual installation script            ($DUAL_SCRIPT)      \033[0m"
echo -e "\033[31m\033[47m=======================================================================\033[0m"
}

# Get StrongVPN ddwrt script to modify it
{
# Tries to guess the StrongVPN script name
GUESS=ovpn???_ddwrt_small.sh

if [ -f $GUESS ];then
echo Is this your file : $GUESS
while true
do
echo -n "Please confirm (y or n): "
read CONFIRM
case $CONFIRM in
y|Y|YES|yes|Yes)
INSTALL_SCRIPT="$GUESS"
break
;;
n|N|no|NO|No)
echo Please input the original installer script name:
read INSTALL_SCRIPT
if [ ! -z $INSTALL_SCRIPT ];then
if [ ! -f $INSTALL_SCRIPT ];then
echo File doesnt exist in this directory
echo are you sure you copied all the files here?
echo Check file name \& copy location then restart.
exit
fi
else
echo Blank file name given, please retry!
exit
fi
break
;;
*) clear | echo Please enter only y or n
esac
done
else
echo Please input the original installer script name:
read INSTALL_SCRIPT
if [ ! -f $INSTALL_SCRIPT ];then
echo File doesnt exist in this directory
echo are you sure you copied all the files here?
echo Check file name \& copy location then restart.
exit
fi
fi
}

# Creating working copy of script
cp $INSTALL_SCRIPT $DUAL_SCRIPT
echo
echo Parsing file info....

# Cleans sed output, adds the necessary escape characters needed.
# Arguments: arg1= variable holding the replacing text
#            arg2(optional)=multi if the variable consists of multiple lines
clean_sed(){
pattern="$1"
safe_pattern=$(echo "$pattern" | sed 's/[][\.*/]/\\&/g; s/$$/\\&/; s/^^/\\&/')
if [ $2 == "multi" ]; then
safe_pattern=$(echo "$safe_pattern" | sed 's/$/\\\\n/')
fi
echo -e $safe_pattern
}

# Modified script text - combined here to make future changes easier
{
#TEXT1
# Replaces openvpn --daemon --config ovpn.conf
{
TEXT1='sh /tmp/etc/config/ovpn.wanup'
}

#TEXT2
# The double slashes are necessary since this text will be ran through sed AND echo -e
# Modifies wanup script
{
TEXT2='echo -e "
#!/bin/sh
killall openvpn
upnp -D -W tun0
ping -c4 localhost

# Clean up by flushing table 4 and deleting all ip rules
ip route flush table 4
ip rule show | grep -Ev \\"^(0|32766|32767)\\" | while read PRIO RULE; do ip rule del prio \\${PRIO%%:*} $( echo \\$RULE | sed \\"s|all|0/0|\\" ); done

# Create backup of default route table
ip route show table main > /tmp/ovpn/route.isp

# start openvpn
openvpn --daemon --config /tmp/ovpn/ovpn.conf

# Add rules for all DHCP routes (192.168.1.100 -> 192.168.1.255)
'$PORT_RANGE'

# Flush route cache
ip route flush cache

">/tmp/etc/config/ovpn.wanup'
}

#TEXT3
#  Modifies ovpn_up script
{
TEXT3='nvram set ovpn_up='"'"'iptables -t nat -A POSTROUTING -o $dev -j MASQUERADE

# Use original (pre-openvpn) route for table 4
cat /tmp/ovpn/route.isp | while read ROUTE; do ip route add table 4 $ROUTE; done'
}

#TEXT4
# Modifies ovpn_dn script
{
TEXT4='killall -HUP dnsmasq

# Clean up by flushing table 4 and deleting all ip rules
ip route flush table 4
ip rule show | grep -Ev "^(0|32766|32767)" | while read PRIO RULE; do ip rule del prio ${PRIO%%:*} $( echo $RULE | sed "s|all|0/0|" ); done'"'"' '
}

#TEXT5
# Add reboot option
{
TEXT5='nvram commit
echo Press any key to reboot.....
read dummy_var
reboot'
}
}

# Do the actual modification using the text above
{
#TEXT1
# Replaces openvpn --daemon --config ovpn.conf
sed -i "s/openvpn --daemon --config ovpn.conf/`clean_sed "$TEXT1"`/" $DUAL_SCRIPT

#TEXT2
# Modifies wanup script
sed -i "s/echo -e.*/`clean_sed "$TEXT2" "multi"`/" $DUAL_SCRIPT

#TEXT3
#  Modifies ovpn_up script
sed -i "s/nvram set ovpn_up.*/`clean_sed "$TEXT3" "multi"`/" $DUAL_SCRIPT

#TEXT4
# Modifies ovpn_dn script
sed -i "s/killall -HUP dnsmasq.*/`clean_sed "$TEXT4" "multi"`/" $DUAL_SCRIPT

#TEXT5
# Add reboot option
sed  -i "s/nvram commit/`clean_sed "$TEXT5" "multi"`/" $DUAL_SCRIPT

#CLEANUP
# Remove blank spaces for clarity
sed -i 's/^ //' $DUAL_SCRIPT
}

# Make script executable
chmod +x $DUAL_SCRIPT

# Ask user if he wants to reboot
{
echo
echo All Done!
echo
echo Would you like to start the OpenVPN DD-WRT install?
echo \(You can manualy install at a later time by running ovpn_dual_ddwrt.sh\)
while true
do
echo -n "Please confirm (y or n): "
read CONFIRM
case $CONFIRM in
y|Y|YES|yes|Yes) break ;;
n|N|no|NO|No)
echo Aborting - You can manualy install at a later time by running ovpn_dual_ddwrt.sh
exit
;;
*) clear | echo Please enter only y or n
esac
done
echo
echo Running the installation script
# Run newly created script
sh $DUAL_SCRIPT
}