Re: [PATCH v2] add stealth mode

From: Matteo Croce <redacted>
Date: Mon, 6 Jul 2015 21:44:06 +0200

2015-07-06 12:49 GMT+02:00  [off-list ref]:

quoted

On Thu, 02 Jul 2015 10:56:01 +0200, Matteo Croce said:

quoted

Add option to disable any reply not related to a listening socket,
like RST/ACK for TCP and ICMP Port-Unreachable for UDP.
Also disables ICMP replies to echo request and timestamp.
The stealth mode can be enabled selectively for a single interface.

A few notes.....

1) Do you have an actual use case where an iptables '-j DROP' isn't usable?

If you mean using a default DROP policy and allowing only the traffic
do you want,
then the use case is where the port can change at runtime and you may not want
to update the firewall every time

Dynamically updated firewalls are "a thing" and quite effective for
solving problems like this one.

With nftables such updates are even extremely efficient.