LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Casey Schaufler <casey@schaufler-ca.com>
To: Tilman Baumann <tilman.baumann@collax.com>
Cc: Linux-Kernel <linux-kernel@vger.kernel.org>,
	linux-security-module@vger.kernel.org
Subject: Re: SMACK netfilter smacklabel socket match
Date: Thu, 25 Sep 2008 20:43:01 -0700	[thread overview]
Message-ID: <48DC5A45.8020801@schaufler-ca.com> (raw)
In-Reply-To: <48DBC9A1.20900@collax.com>

Tilman Baumann wrote:
> Hi all,
>
> i made some SMACK related patches. I hope this list is the right place 
> to post them.

Here and, probably more importantly 
linux-security-module@vger.kernel.org as that's
my primary hang out.

> The intention behind this patch is that i needed a way to (firewall) 
> match for packets originating from specific processes.
> The existing owner match did not work well enough, especially since 
> the cmd-owner part is removed.
> Then i thought about a way to tag processes and somehow match this tag 
> in the firewall.
> I recalled that SELinux can do this (SECMARK) but SELinux would have 
> been way to complex for what i want. But the idea was born, i just 
> needed something more simple.
>
> SMACK seemed to be the right way. So i made a little primitive 
> netfilter match to match against the security context of sockets.
> SMACK does CIPSO labels, but this was not what i wanted, i wanted to 
> label the socket not the packet (on the wire).
> This of course only works for packets with a local socket, but this 
> was my intention anyway.
>
> This way i can label a process and all it's sockets carry the same 
> label which i then can use to match against in the firewall.
>

Hmm. It looks as if your code will do what you're asking it to do.
Are you going to be happy with the access restrictions that will be
imposed by Smack?

> The code is pretty much based on cargo cult coding from other 
> netfilter matches, especially the owner match (which turned out to be 
> a bad reference since it is crapped with tons of compat interfaces).
>
> I have no kernel coding experience whatsoever and little C coding 
> history. So i would really like you guys to look over it a bit.
>
> Originally i intended to put this mask in the xtables_match structure.
> .hooks = (1 << NF_INET_LOCAL_OUT) | (1 << NF_INET_LOCAL_IN)
> But it turned out that i then could not longer put the rule in a chain 
> which is called by the OUTPUT chain but only in OUTPUT directly.
> I did not investigate much more since i did not really understand this 
> part. Allowing the user to add this match wherever he wants to does 
> not hurt, if there is no local socket there is no matching.
> But maybe this is something that should be changed.
>
> About the Files:
> SMACK-netfilter-socket-label-match.patch
> is a git patch for the current kernel.
>
> iptables-smacklabel.patch
> contains the iptables userspace part (applies to iptables-1.4.1.1)
>
>
> Regards
>  Tilman Baumann


  parent reply	other threads:[~2008-09-26  3:43 UTC|newest]

Thread overview: 30+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-09-25 17:25 Tilman Baumann
2008-09-25 18:26 ` Paul Moore
2008-09-25 19:26   ` Tilman Baumann
2008-09-25 19:57     ` Paul Moore
2008-09-25 20:32       ` Tilman Baumann
2008-09-26 12:35   ` Tilman Baumann
2008-09-26 19:55     ` Paul Moore
2008-09-26  3:43 ` Casey Schaufler [this message]
2008-09-26  8:19   ` Tilman Baumann
2008-09-27  5:01     ` Casey Schaufler
2008-09-29 16:21       ` Tilman Baumann
2008-09-30  3:29         ` Casey Schaufler
2008-10-01 11:29           ` Tilman Baumann
2008-10-01 15:21             ` Casey Schaufler
2008-10-01 16:55               ` Tilman Baumann
2008-10-01 18:22                 ` Casey Schaufler
2008-10-06 12:57                   ` Tilman Baumann
2008-10-06 23:05                     ` Ahmed S. Darwish
2008-10-07  2:42                     ` Casey Schaufler
2008-10-17 16:57                       ` Tilman Baumann
2008-10-17 17:53                         ` Casey Schaufler
2008-10-20 12:06                           ` Tilman Baumann
2008-10-20 15:01                             ` Casey Schaufler
2008-10-22  3:36                             ` Casey Schaufler
2008-10-30 16:06                               ` Tilman Baumann
2008-10-31  3:46                                 ` Casey Schaufler
2008-12-11  0:03                                 ` Casey Schaufler
2008-12-11 10:18                                   ` Tilman Baumann
2008-12-11 16:29                                     ` Casey Schaufler
2008-10-23 11:55                           ` Paul Moore

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=48DC5A45.8020801@schaufler-ca.com \
    --to=casey@schaufler-ca.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-security-module@vger.kernel.org \
    --cc=tilman.baumann@collax.com \
    --subject='Re: SMACK netfilter smacklabel socket match' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).