how to combine bash cycle for with different variables

Question

I have two networks:

FORWARDS="10.0.0.0/8 192.168.0.0/16"

In cycle I'm allowing tcp udp icmp from same network to same

for ipo in $FORWARDS;do
    iptables -A FORWARD -p tcp -s $ipo -d $ipo -j ACCEPT
    iptables -A FORWARD -p udp -s $ipo -d $ipo -j ACCEPT
    iptables -A FORWARD -p icmp -s $ipo -d $ipo -j ACCEPT
done

But I need to allow same networks from one to eachother, howto add iptables rules below in cycle to reduce number of lines:

iptables -A FORWARD -p tcp -s 10.0.0.0/8 -d 192.168.0.0/16 -j ACCEPT
iptables -A FORWARD -p tcp -s 192.168.0.0/16 -d 10.0.0.0/8 -j ACCEPT
iptables -A FORWARD -p udp -s 10.0.0.0/8 -d 192.168.0.0/16 -j ACCEPT
iptables -A FORWARD -p udp -s 192.168.0.0/16 -d 10.0.0.0/8 -j ACCEPT
iptables -A FORWARD -p icmp -s 10.0.0.0/8 -d 192.168.0.0/16 -j ACCEPT
iptables -A FORWARD -p icmp -s 192.168.0.0/16 -d 10.0.0.0/8 -j ACCEPT

score 0 · Answer 1 · answered Mar 12 '15 at 07:31

0

Use nested loops:

for ipo1 in $FORWARDS; do
    for ip2 in $FORWARD; do
        iptables -A FORWARD -p tcp -s $ipo1 -d $ipo2 -j ACCEPT
        iptables -A FORWARD -p udp -s $ipo1 -d $ipo2 -j ACCEPT
        iptables -A FORWARD -p icmp -s $ipo1 -d $ipo2 -j ACCEPT
    done
done

answered Mar 12 '15 at 07:31

Barmar

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and allow forward from $ipo1 to $ipo1? I ment in one cycle... if any how it's possible... – Asunta Mar 12 '15 at 08:00
It will get those whenever `$ipo1` and `$ipo2` are the same. – Barmar Mar 12 '15 at 08:01
sorry it's ok, my mistake and yours in second line ip2 variable – Asunta Mar 12 '15 at 08:25

how to combine bash cycle for with different variables

1 Answers1