|| ||"Tvrtko A. Ursulin" <tvrtko.ursulin-AT-sophos.com>|
|| ||Out of tree module using LSM|
|| ||Wed, 28 Nov 2007 12:42:52 +0000|
Hi Linus, all,
During one recent LKML discussion
(http://marc.info/?l=linux-kernel&m=119267398722085&...) about LSM going
static you called for LSM users to speak up.
We here at Sophos (the fourth largest endpoint security vendor in the world)
have such a module called Talpa which is a part of our main endpoint security
product for Linux that protects from viruses and malware hosted on Linux,
including those targetting Windows or other connected devices,
which is GPL code and has been in the field for almost three years now. It's
source code has been shipping with the product from the start. We also have
a SourceForge project at http://sourceforge.net/projects/talpa/ to host it.
In essence, what our module does is it intercepts file accesses and allows
userspace daemons to vet them. One of the means we implemented that is
through LSM and although it is not a perfect match for such use we prefer to
use an official interface. Unfortunately, with time it became impossible to
use LSM on some distributions (SELinux) so we had to implement other
intercept methods which are significantly less nice, and which may also
become unworkable over time.
The main point here is that making LSM not available for modules makes our
life even more difficult and we would like to ask you to revert that change
until another acceptable, secure solution is found.
At this point I would not like this to turn into a discussion on technical or
code merits of our current approach. It is just that usage scenarios of
(dis-)allowing access to files based on their content, regardless of the
actual details, do sound like a reasonable idea. What we would like to do is
to start discussion about possible solutions in which other interested
parties will hopefully join and in future create some progress on this front.
Tvrtko August Ursulin
Senior Software Engineer, Sophos
Tel: 01235 559933
Protecting business against viruses, spyware, spam and policy abuse
Sophos Plc, The Pentagon, Abingdon Science Park, Abingdon,
OX14 3YP, United Kingdom.
Company Reg No 2096520. VAT Reg No GB 348 3873 20.
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