netdev - Re: [PATCH net-next] net: tcp_probe: allow more advanced ingress filtering by mark

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]

Message-ID: <1377270813.8828.6.camel@edumazet-glaptop>
Date:	Fri, 23 Aug 2013 08:13:33 -0700
From:	Eric Dumazet <eric.dumazet@...il.com>
To:	Daniel Borkmann <dborkman@...hat.com>
Cc:	davem@...emloft.net, netdev@...r.kernel.org
Subject: Re: [PATCH net-next] net: tcp_probe: allow more advanced ingress
 filtering by mark

On Fri, 2013-08-23 at 16:16 +0200, Daniel Borkmann wrote:
> Currently, the tcp_probe snooper can either filter packets by a given
> port (handed to the module via module parameter e.g. port=80) or lets
> all TCP traffic pass (port=0, default). When a port is specified, the
> port number is tested against the sk's source/destination port. Thus,
> if one of them matches, the information will be further processed for
> the log.
> 
> As this is quite limited, allow for more advanced filtering possibilities
> which can facilitate debugging/analysis with the help of the tcp_probe
> snooper. Therefore, similarly as added to BPF machine in commit 7e75f93e
> ("pkt_sched: ingress socket filter by mark"), add the possibility to
> use skb->mark as a filter.
> 
> If the mark is not being used otherwise, this allows ingress filtering
> by flow (e.g. in order to track updates from only a single flow, or a
> subset of all flows for a given port) and other things such as dynamic
> logging and reconfiguration without removing/re-inserting the tcp_probe
> module, etc. Simple example:
> 
>   insmod net/ipv4/tcp_probe.ko fwmark=8888 full=1
>   ...
>   iptables -A INPUT -i eth4 -t mangle -p tcp --dport 22 \
>            --sport 60952 -j MARK --set-mark 8888
>   [... sampling interval ...]
>   iptables -D INPUT -i eth4 -t mangle -p tcp --dport 22 \
>            --sport 60952 -j MARK --set-mark 8888
> 
> The current option to filter by a given port is still being preserved. A
> similar approach could be done for the sctp_probe module as a follow-up.
> 
> Signed-off-by: Daniel Borkmann <dborkman@...hat.com>
> ---

Well, why not adding ability to load/use a BPF filter instead ? ;)



--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html