[Bug 1448] New: SNAT/DNAT/Masquerading not working for UDPLite protocol

bugzilla-daemon at netfilter.org bugzilla-daemon at netfilter.org
Tue Aug 4 12:04:08 CEST 2020


https://bugzilla.netfilter.org/show_bug.cgi?id=1448

            Bug ID: 1448
           Summary: SNAT/DNAT/Masquerading not working for UDPLite
                    protocol
           Product: netfilter/iptables
           Version: unspecified
          Hardware: x86_64
                OS: other
            Status: NEW
          Severity: normal
          Priority: P5
         Component: NAT
          Assignee: netfilter-buglog at lists.netfilter.org
          Reporter: me at nicho1as.wang

It was first observed on Arch Linux with a 5.7.10 kernel, serving as a router
with the following rules,

iptables -A POSTROUTING -t nat -o br-wan -j MASQUERADE
iptables -A FORWARD -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
iptables -A FORWARD -i br-lan -o br-wan -j ACCEPT

, and it seems the packet are NAT'd as a general IP packet (the server receives
a lan ip address).

Then I tried to add the following NAT rules but it cannot match to any packet.
iptables -I POSTROUTING 1 -tnat -j SNAT -p udplite -o br-wan --to [wan_ip]
iptables -I PREROUTING 1 -tnat -j DNAT -p udplite -i br-lan --to [lan_ip]

The tool I wrote for testing this behavior is hosted at
https://github.com/nicholascw/SLOWProxy/tree/develop/gadgets/udpliteping, which
is a simple ping-n-pong sketch.

-- 
You are receiving this mail because:
You are watching all bug changes.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.netfilter.org/pipermail/netfilter-buglog/attachments/20200804/4932e8dc/attachment.html>


More information about the netfilter-buglog mailing list