#!/bin/bash
# $Id$
iptables="/sbin/iptables"
iptablesrestore="/sbin/iptables-restore"
ifconfig="/sbin/ifconfig"
grep="/bin/grep"
cut="/usr/bin/cut"
ipcalc="/usr/bin/ipcalc"

#pimp files must be generated by optional-tools/make-pimp utility
pimp_2way_nat="/dev/shm/pimp-2way-nat.tmp"
pimp_snat="/dev/shm/pimp-snat.tmp"
etchosts="/mnt/mtdblock0/hosts"
restoretmp="/dev/shm/iptables-restore.tmp"
restoredata="/mnt/mtdblock0/iptables-restore.in"
wan1="vlan770"
wan2="vlan771"
wan3="vlan772"
wan4="vlan774"
czffirstbitmask="19"
czfsecondbitmask="22"
czfthirdbitmask="25"
czffourthbitmask="28"
pubfirstbitmask="26"
pubsecondbitmask="29"
chaintrack="_"

echo "*nat" > $restoretmp
echo ":PREROUTING ACCEPT [0:0]" >> $restoretmp
echo ":POSTROUTING ACCEPT [0:0]" >> $restoretmp
echo ":OUTPUT ACCEPT [0:0]" >> $restoretmp

# ===============================================================
#  Symetrical SNAT-DNAT using indexed iptables
# ===============================================================
echo -n "Generating new iptables-restore data - two way SNAT/DNAT "

for czfip in `$grep -v ^# $pimp_2way_nat|$cut -f 1 -d " "`
do
 pubip=`$grep "$czfip " $pimp_2way_nat|$cut -f 2 -d " "`
 czffirstindex=priv_`$ipcalc -n $czfip/$czffirstbitmask|$grep Network|$cut -f 4 -d \ |tr [./] _`
 czfsecondindex=priv_`$ipcalc -n $czfip/$czfsecondbitmask|$grep Network|$cut -f 4 -d \ |tr [./] _`
 czfthirdindex=priv_`$ipcalc -n $czfip/$czfthirdbitmask|$grep Network|$cut -f 4 -d \ |tr [./] _`
 czffourthindex=priv_`$ipcalc -n $czfip/$czffourthbitmask|$grep Network|$cut -f 4 -d \ |tr [./] _`
 pubfirstindex=pub_`$ipcalc -n $pubip/$pubfirstbitmask|$grep Network|$cut -f 4 -d \ |tr [./] _`
 pubsecondindex=pub_`$ipcalc -n $pubip/$pubsecondbitmask|$grep Network|$cut -f 4 -d \ |tr [./] _`

 if ! [[ "$chaintrack" == *"$czffirstindex"* ]]
 then
  echo :$czffirstindex "- [0:0]" >> $restoretmp
  s=`$ipcalc -n $czfip/$czffirstbitmask|$grep Network|$cut -f 4 -d \ `
  echo -A POSTROUTING -d ! 10.0.0.0/8 -s $s -o $wan1 -j $czffirstindex >> $restoretmp
  echo -A POSTROUTING -d ! 10.0.0.0/8 -s $s -o $wan2 -j $czffirstindex >> $restoretmp
  echo -A POSTROUTING -d ! 10.0.0.0/8 -s $s -o $wan3 -j $czffirstindex >> $restoretmp
  echo -A POSTROUTING -d ! 10.0.0.0/8 -s $s -o $wan4 -j $czffirstindex >> $restoretmp
  chaintrack=\ ${czffirstindex}\ ${chaintrack}
 fi

 if ! [[ "$chaintrack" == *"$czfsecondindex"* ]]
 then
  echo :$czfsecondindex "- [0:0]" >> $restoretmp
  s=`$ipcalc -n $czfip/$czfsecondbitmask|$grep Network|$cut -f 4 -d \ `
  echo -A $czffirstindex -s $s -o $wan1 -j $czfsecondindex >> $restoretmp
  echo -A $czffirstindex -s $s -o $wan2 -j $czfsecondindex >> $restoretmp
  echo -A $czffirstindex -s $s -o $wan3 -j $czfsecondindex >> $restoretmp
  echo -A $czffirstindex -s $s -o $wan4 -j $czfsecondindex >> $restoretmp
  chaintrack=\ ${czfsecondindex}\ ${chaintrack}
 fi

 if ! [[ "$chaintrack" == *"$czfthirdindex"* ]]
 then
  echo :$czfthirdindex "- [0:0]" >> $restoretmp
  s=`$ipcalc -n $czfip/$czfthirdbitmask|$grep Network|$cut -f 4 -d \ `
  echo -A $czfsecondindex -s $s -o $wan1 -j $czfthirdindex >> $restoretmp
  echo -A $czfsecondindex -s $s -o $wan2 -j $czfthirdindex >> $restoretmp
  echo -A $czfsecondindex -s $s -o $wan3 -j $czfthirdindex >> $restoretmp
  echo -A $czfsecondindex -s $s -o $wan4 -j $czfthirdindex >> $restoretmp
  chaintrack=\ ${czfthirdindex}\ ${chaintrack}
 fi

 if ! [[ "$chaintrack" == *"$czffourthindex"* ]]
 then
  echo :$czffourthindex "- [0:0]" >> $restoretmp
  s=`$ipcalc -n $czfip/$czffourthbitmask|$grep Network|$cut -f 4 -d \ `
  echo -A $czfthirdindex -s $s -o $wan1 -j $czffourthindex >> $restoretmp
  echo -A $czfthirdindex -s $s -o $wan2 -j $czffourthindex >> $restoretmp
  echo -A $czfthirdindex -s $s -o $wan3 -j $czffourthindex >> $restoretmp
  echo -A $czfthirdindex -s $s -o $wan4 -j $czffourthindex >> $restoretmp
  chaintrack=\ ${czffourthindex}\ ${chaintrack}
 fi

 if ! [[ "$chaintrack" == *"$pubfirstindex"* ]]
 then
  echo :$pubfirstindex "- [0:0]" >> $restoretmp
  s=`$ipcalc -n $pubip/$pubfirstbitmask|$grep Network|$cut -f 4 -d \ `
  echo -A PREROUTING -i $wan1 -d $s -j $pubfirstindex >> $restoretmp
  echo -A PREROUTING -i $wan2 -d $s -j $pubfirstindex >> $restoretmp
  echo -A PREROUTING -i $wan3 -d $s -j $pubfirstindex >> $restoretmp
  echo -A PREROUTING -i $wan4 -d $s -j $pubfirstindex >> $restoretmp
  chaintrack=\ ${pubfirstindex}\ ${chaintrack}
 fi

 if ! [[ "$chaintrack" == *"$pubsecondindex"* ]]
 then
  echo :$pubsecondindex "- [0:0]" >> $restoretmp
  s=`$ipcalc -n $pubip/$pubsecondbitmask|$grep Network|$cut -f 4 -d \ `
  echo -A $pubfirstindex -i $wan1 -d $s -j $pubsecondindex >> $restoretmp
  echo -A $pubfirstindex -i $wan2 -d $s -j $pubsecondindex >> $restoretmp
  echo -A $pubfirstindex -i $wan3 -d $s -j $pubsecondindex >> $restoretmp
  echo -A $pubfirstindex -i $wan4 -d $s -j $pubsecondindex >> $restoretmp
  chaintrack=\ ${pubsecondindex}\ ${chaintrack}
 fi

 echo -A $pubsecondindex -i $wan1 -d $pubip/32 -j DNAT --to-destination $czfip >> $restoretmp
 echo -A $pubsecondindex -i $wan2 -d $pubip/32 -j DNAT --to-destination $czfip >> $restoretmp
 echo -A $pubsecondindex -i $wan3 -d $pubip/32 -j DNAT --to-destination $czfip >> $restoretmp
 echo -A $pubsecondindex -i $wan4 -d $pubip/32 -j DNAT --to-destination $czfip >> $restoretmp

 echo -A $czffourthindex -s $czfip/32 -o $wan1 -j SNAT --to-source $pubip >> $restoretmp
 echo -A $czffourthindex -s $czfip/32 -o $wan2 -j SNAT --to-source $pubip >> $restoretmp
 echo -A $czffourthindex -s $czfip/32 -o $wan3 -j SNAT --to-source $pubip >> $restoretmp
 echo -A $czffourthindex -s $czfip/32 -o $wan4 -j SNAT --to-source $pubip >> $restoretmp

 echo -n .

done
echo " done."

# ===============================================================
#  SNAT only using indexed iptables (should be rather function, hmm)
# ===============================================================
echo -n "Generating new iptables-restore data - one way SNAT "

for czfip in `$grep -v ^# $pimp_snat|$cut -f 1 -d " "`
do
 pubip=`$grep "$czfip " $pimp_snat|$cut -f 2 -d " "`
 czffirstindex=priv_`$ipcalc -n $czfip/$czffirstbitmask|$grep Network|$cut -f 4 -d \ |tr [./] _`
 czfsecondindex=priv_`$ipcalc -n $czfip/$czfsecondbitmask|$grep Network|$cut -f 4 -d \ |tr [./] _`
 czfthirdindex=priv_`$ipcalc -n $czfip/$czfthirdbitmask|$grep Network|$cut -f 4 -d \ |tr [./] _`
 czffourthindex=priv_`$ipcalc -n $czfip/$czffourthbitmask|$grep Network|$cut -f 4 -d \ |tr [./] _`

 if ! [[ "$chaintrack" == *"$czffirstindex"* ]]
 then
  echo :$czffirstindex "- [0:0]" >> $restoretmp
  s=`$ipcalc -n $czfip/$czffirstbitmask|$grep Network|$cut -f 4 -d \ `
  echo -A POSTROUTING -d ! 10.0.0.0/8 -s $s -o $wan1 -j $czffirstindex >> $restoretmp
  echo -A POSTROUTING -d ! 10.0.0.0/8 -s $s -o $wan2 -j $czffirstindex >> $restoretmp
  echo -A POSTROUTING -d ! 10.0.0.0/8 -s $s -o $wan3 -j $czffirstindex >> $restoretmp
  echo -A POSTROUTING -d ! 10.0.0.0/8 -s $s -o $wan4 -j $czffirstindex >> $restoretmp
  chaintrack=\ ${czffirstindex}\ ${chaintrack}
 fi

 if ! [[ "$chaintrack" == *"$czfsecondindex"* ]]
 then
  echo :$czfsecondindex "- [0:0]" >> $restoretmp
  s=`$ipcalc -n $czfip/$czfsecondbitmask|$grep Network|$cut -f 4 -d \ `
  echo -A $czffirstindex -s $s -o $wan1 -j $czfsecondindex >> $restoretmp
  echo -A $czffirstindex -s $s -o $wan2 -j $czfsecondindex >> $restoretmp
  echo -A $czffirstindex -s $s -o $wan3 -j $czfsecondindex >> $restoretmp
  echo -A $czffirstindex -s $s -o $wan4 -j $czfsecondindex >> $restoretmp
  chaintrack=\ ${czfsecondindex}\ ${chaintrack}
 fi

 if ! [[ "$chaintrack" == *"$czfthirdindex"* ]]
 then
  echo :$czfthirdindex "- [0:0]" >> $restoretmp
  s=`$ipcalc -n $czfip/$czfthirdbitmask|$grep Network|$cut -f 4 -d \ `
  echo -A $czfsecondindex -s $s -o $wan1 -j $czfthirdindex >> $restoretmp
  echo -A $czfsecondindex -s $s -o $wan2 -j $czfthirdindex >> $restoretmp
  echo -A $czfsecondindex -s $s -o $wan3 -j $czfthirdindex >> $restoretmp
  echo -A $czfsecondindex -s $s -o $wan4 -j $czfthirdindex >> $restoretmp
  chaintrack=\ ${czfthirdindex}\ ${chaintrack}
 fi

 if ! [[ "$chaintrack" == *"$czffourthindex"* ]]
 then
  echo :$czffourthindex "- [0:0]" >> $restoretmp
  s=`$ipcalc -n $czfip/$czffourthbitmask|$grep Network|$cut -f 4 -d \ `
  echo -A $czfthirdindex -s $s -o $wan1 -j $czffourthindex >> $restoretmp
  echo -A $czfthirdindex -s $s -o $wan2 -j $czffourthindex >> $restoretmp
  echo -A $czfthirdindex -s $s -o $wan3 -j $czffourthindex >> $restoretmp
  echo -A $czfthirdindex -s $s -o $wan4 -j $czffourthindex >> $restoretmp
  chaintrack=\ ${czffourthindex}\ ${chaintrack}
 fi

 echo -A $czffourthindex -s $czfip/32 -o $wan1 -j SNAT --to-source $pubip >> $restoretmp
 echo -A $czffourthindex -s $czfip/32 -o $wan2 -j SNAT --to-source $pubip >> $restoretmp
 echo -A $czffourthindex -s $czfip/32 -o $wan3 -j SNAT --to-source $pubip >> $restoretmp
 echo -A $czffourthindex -s $czfip/32 -o $wan4 -j SNAT --to-source $pubip >> $restoretmp

 echo -n .
done
echo " done."

echo COMMIT >> $restoretmp
echo -n "Writing $restoredata"
mv $restoretmp $restoredata