ubuntu/ip-redirect-all

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# Redirect TCP/IP traffic to all local addresses from one port to another
# Example: ip-redirect-all 80 8090

here=`echo "import os; print os.path.realpath('$0')" | python`; here=`dirname $here`
sport=$1
tport=$2

# Cleanup existing rules
sudo /sbin/iptables -t nat -S PREROUTING | grep "\-p tcp" | grep "\-\-dport $sport" | grep "\-j REDIRECT" | sed "s/^-A/-D/" | awk -F "\t" '{ printf "sudo /sbin/iptables -t nat %s\n", $1 }' | /bin/sh
sudo /sbin/iptables -t nat -S OUTPUT | grep "\-p tcp" | grep "\-\-dport $sport" | grep "\-j REDIRECT" | sed "s/^-A/-D/" | awk -F "\t" '{ printf "sudo /sbin/iptables -t nat %s\n", $1 }' | /bin/sh

# Redirect traffic
/sbin/ifconfig | grep "inet addr:" | awk -F ":" '{ print $2 }' | awk '{ print $1 }' | xargs -i $here/ip-redirect $sport $tport {}