Hello,
I may find out the answer by myself, but may be useful to someone else...

I have an embedded router that runs openwrt.

I'd like to be able to read the firewall rules from iptables,
you can see all rules from iptables -nvL
How I can identify the rules for port forwarding or dmz? in particolar, I
need to know the range of ports that are in port forwarding, or if all ports
have been forwarded to dmz on the lan. I know this is wrong, but this is
what I do:

DMZ for all ports:
iptables -nvL zone_dmz_forward | grep -e '*' | grep -v 'dpts:' | awk '{
print $9 }' | grep -v '0.0.0.0'

port ranges:
iptables -nvL | grep -e 'tcp dpts' | awk -F ':' '{ print $3":"$2 }' | sed
's/ //g'
iptables -nvL | grep -e 'tcp spts' | awk -F ':' '{ print $5":"$4 }' | sed
's/ //g'

single port:

iptables -nvL | grep 'tcp dpt:' | grep -e '*' -e 'ppp' | cut -d ':' -f 2


Thanks in advance

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