I have the following iptables rules for a CentOS7 web server. I would like to get ip6tables equivalent rules for them. Please let me know, if any changes are required between these and ip6tables rules -

iptables -A INPUT -p tcp --tcp-flags ALL NONE -j DROP
(tcp flag NONE packets)

iptables -A INPUT -p tcp ! --syn -m state --state NEW -j DROP
(syn attacks, new connection without communication of purpose)

iptables -A INPUT -p tcp --tcp-flags ALL ALL -j DROP
(XMAS packet)

iptables -A INPUT -i lo -j ACCEPT
(allow localhost)

iptables -A INPUT -p tcp -m tcp --dport 80 -j ACCEPT
(allow port 80)

iptables -A INPUT -p tcp -m tcp --dport 443 -j ACCEPT
(allow port 443)

iptables -A INPUT -p tcp -m tcp --dport 22 -j ACCEPT
(allow ssh at port 22)

iptables -A INPUT -p icmp -m icmp --icmp-type address-mask-request -j DROP
(drop pings asking for address)

iptables -A INPUT -p icmp -m icmp --icmp-type timestamp-request -j DROP
(drop pings asking for timestamp)

iptables -A INPUT -p icmp -m icmp --icmp-type 8 -m limit --limit 5/second -j ACCEPT
(allow max 5 pings per second, beyond that, pings will be dropped, to prevent ping flooding)

iptables -I INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
(allow established and once connected connections)

(allow all outgoing packets)

iptables -P INPUT DROP
(disallow all incoming packets, except the ones stated above)
  • You don't use source/destination IPv4 IPs / subnets, so no, you won't have to change that. The only thing are your icmp rules. You'll need ipv6-icmp or -p icmpv6 --icmpv6-type 1/2/..., amongst other options, depends on what you want to do. – Lenniey Jan 24 '18 at 11:05
  • 1
    Use firewalld instead. Don't try to write a manual firewall anymore, especially since this one appears to have originated with an obsolete and not very good Internet tutorial. And remember that blocking ICMP on IPv6 is a great way to break connectivity. If you must write a firewall manually, see this. – Michael Hampton Jan 24 '18 at 18:55
  • Hi Michael, thanks for your comment. Could you please elaborate which of the above rules are not ideal / obsolete, so that I can make the necessary changes. Thanks. – vjjj Jan 24 '18 at 19:24

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