Linux in Government: Security Enhanced Linux - The Future is Now

An interview with Bill McCarty, author of a new book on SELinux, about the potential SELinux holds for secure computing.


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also - systrace?

Anonymous's picture

I'm also interested in a comparison to systrace. Systrace is what OpenBSD uses - and they are not exactly known for not knowing security. It should also be less intrusive, and less ressource-intensive.

What about the TCO hit because of SELinux?

Ahmed Masud's picture

Dear All (these are just my 2c worth):

While SELinux contributes greatly to the technology side of the coin, itfails to address the economics of security. The litmus test is definitely how many nodes will actually RUN SELinux. However, the classification of why they CANNOT run it is also an important piece of information.

SELinux comes out of National Defense paradigm, namely: Achieve the goal no matter what the cost, because there is (relatively) infinite money and infinite resources. This is not practical for a normal business which has cost constraints.

IMHO SELinux doesn't address vital ROI and TCO concerns. I would've liked to see questions regarding that direction in this interview - and i haven't zipped through the book ;) so i am not sure if the good Author has touched on this topic.



targeted policy solves this

Russell Coker.'s picture

The "targeted" policy which is in Fedora Core 3 and will be in Red Hat Enterprise Linux 4 solves this. It restricts only the daemons that are at most danger (network facing daemons initially but as we progress we will add other daemons to the list). This stops quite a number of attack vectors while having no restrictions on users who login to the system. Of course this means that targeted policy doesn't prevent a local user from attacking the system, but that is a trade-off that the administrator can make for ease of use.

A system running the targeted policy should in most cases be indistinguishable from a non-SE system. The only reported problems of the targeted policy are related to Apache - a daemon that needs protection but is very difficult to write policy for because it's so configurable.

In Fedora Core 3 and Red Hat Enterprise Linux 4 SE Linux is enabled by default and installed with only the targeted policy. In Fedora you can convert the system to "strict" policy after completing the install if you desire better security and are happy to trade-off some ease of use to get it.

The standard support agreements for RHEL will only include targeted policy. This does not prevent you from using strict policy on a RHEL system, but the support agreement does not cover problems with strict policy.

Currently we have no plans to make future releases of either Fedora or RHEL default to strict policy.

Hi, It is a good interview

Anonymous's picture


It is a good interview but why there are no questions about alternative of SElinux like grsecurity. It would be interesting to have the opinion of Bill about the advantage/inconvenient of selinux comparing to grsecurity.