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: Wed, 01 Oct 2008 08:21:30 -0700 [thread overview]
Message-ID: <48E3957A.7040201@schaufler-ca.com> (raw)
In-Reply-To: <48E35F36.4030203@collax.com>
Tilman Baumann wrote:
> Casey Schaufler wrote:
>>> Casey Schaufler wrote:
>> If you really want to be abusive you could replace the smack_access()
>> function in security/smack/smack_access.c (of all places) with a no-op
>> returning 0 in all cases.
>
> I thought of that too. :)
> But i would rather like to use the thing in it's intended function
> sometime in the future.
Even better.
>>> What I then to is write iptables OUTPUT chain matches which match
>>> for any of these labels and set some connection marks and firewall
>>> marks.
>>> Which I then can use in routing rules to give different routing
>>> rules to specific processes. (Like all proxy traffic over a second
>>> DSL line)
>>>
>>> I know, it's totally crazy. But it seems to work. :)
>>> I just hope the security part of this all will not break anything.
>>> But it does not look like it would right now.
>>
>> Smack will eventually bite you if you're not careful, but users of
>> MAC systems wouldn't be surprised by that.
> Speaking of the devil...
> This is exactly what happened to me right now. I have problems with
> _some_ https connects. The problem lies somewhere in openssl.
> I did not yet find any clue with strace.
> Is there some straight forward way to audit/debug LSM interventions?
strace is probably your best bet, as it will tell you what syscalls
fail. Your current situation is most likely a case where your program
running with a label "Foo" is trying to communicate with a service on
a machine that doesn't talk CIPSO and hence Smack is treating all
packets to and from that host with the ambient (%cat /smack/ambient)
label, which is "_" unless you've changed it.
> I have probably missed something that a labeled process could not do
> as a '_' process could. Have no idea right now, but it is probably
> something stupidly simple.
>
A labeled system hoping to get services from an unlabeled server is the
biggest
single pain in dealing with labeled systems. Per-host labeling is in the
works,
and it will help in some cases. What I really need is a way to designate an
unlabeled host as safe to talk to at any label, but it will take some
serious
work to come up with a scheme that makes that palatable for a labeled
environment.
I know that SELinux allows for it, but the purist in me has serious doubts.
>> I don't think it's crazy,
>> I think it's a matter of using what's available in novel ways.
> I like that attitude. :)
It got me where I am today. Hmm, maybe you should be just a little bit
careful.
next prev parent reply other threads:[~2008-10-01 15:21 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-09-25 17:25 SMACK netfilter smacklabel socket match 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
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 [this message]
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=48E3957A.7040201@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 \
/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
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
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).