From: Pablo Neira Ayuso <pablo@netfilter.org>
To: backup95 <backup95@netcabo.pt>
Cc: netfilter@vger.kernel.org
Subject: Re: Using NFQUEUE from userspace with seteuid
Date: Mon, 01 Mar 2010 21:10:00 +0100 [thread overview]
Message-ID: <4B8C1F18.8010902@netfilter.org> (raw)
In-Reply-To: <1267410505.18948.46.camel@r1>
backup95 wrote:
> Hello,
>
> I wrote a daemon to do packet filtering using libnetfilter-queue.
>
> It works well except that I ran into problems trying to run it
> seteuid/setegid to an unpriviliged user.
>
> Setup and teardown proceeds as root but when I try running the main loop
> seteuid/setegid to a regular user (just processing IP addresses and
> calling nfq_set_verdict really) everything slows to a crawl. I don't get
> any software errors (packets are apparently received and accepted/denied
> as usual) but all my connections time out or error out (not sure which
> yet). Like I said, works fine as root.
>
> I'm at a loss to explain this because as far as I can tell the
> underlying netlink socket mechanism should not depend on root
> priviledges to send messages. It's strange enough that there's a
> significant slow down but no hard errors (and by that I mean
> nfq_set_verdict returning a negative value).
>
> Can anyone at least please confirm that it should work fine and it is
> worth investigating or else just forget it and run the whole thing as
> root?
>
> Any comments would be greatly appreciated.
Could you post the code or a sketch with the relevant section that I
could use to reproduce the problem here?
next prev parent reply other threads:[~2010-03-01 20:10 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-03-01 2:28 Using NFQUEUE from userspace with seteuid backup95
2010-03-01 20:10 ` Pablo Neira Ayuso [this message]
2010-03-02 3:32 ` backup95
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