linux-kernel - Re: [PATCH v4] add stealth mode

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Wed, 16 Sep 2015 13:06:29 +0200
From:	Florian Westphal <fw@...len.de>
To:	Matteo Croce <matteo@...nwrt.org>
Cc:	David Miller <davem@...emloft.net>, netdev@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH v4] add stealth mode

Matteo Croce <matteo@...nwrt.org> wrote:
> 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.

I think it would make more sense to extend the socket match
in xtables if it can't be used to achive this already.

seems like
*filter
:INPUT ACCEPT [0:0]
-A INPUT -p tcp -m socket --nowildcard -j ACCEPT
-A INPUT -p tcp -j DROP
COMMIT

Already does what you want for tcp, udp should work too.
I'd much rather see xtables and/or nftables to be extended
with whatever feature(s) are needed to configure such a policy
rather than pushing this into the core network stack.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/