Iptables tcpmss rule

Installing and Using OpenWrt
1

Hi all. How can I apply this rule?

## Blocking non-standard MSS values
iptables -A INPUT -i eth0 -p tcp -m conntrack --ctstate NEW -m tcpmss ! --mss 536:65535 -j DROP

iptables v1.8.3 (legacy): Couldn't load match `tcpmss':No such file or directory

2

Works fine for me.

root@magiatiko:[/]#iptables -A INPUT -i eth0.2 -p tcp -m conntrack --ctstate NEW -m tcpmss ! --mss 100:65000 -j DROP
root@magiatiko:[/]#iptables -v
iptables v1.8.4 (legacy): no command specified
Try `iptables -h' or 'iptables --help' for more information.
root@magiatiko:[/]#iptables-save | grep tcpms
-A INPUT -i eth0.2 -p tcp -m conntrack --ctstate NEW -m tcpmss ! --mss 100:65000 -j DROP

root@magiatiko:[/]#opkg list-installed | grep iptables
iptables - 1.8.4-1
iptables-mod-conntrack-extra - 1.8.4-1
iptables-mod-geoip - 3.10-1
iptables-mod-ipopt - 1.8.4-1
iptables-mod-quota2 - 3.10-1
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