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David P. Quigley wrote: > On Fri, 2008-08-22 at 14:34 -0500, Serge E. Hallyn wrote:
>> In August 2006 I posted a patch to the selinux list generating a minimal
>> SELinux policy. This week, David P. Quigley posted an updated version
>> of that as a patch against the kernel. In addition to some fixes, also
>> had nice logic for auto-installing the policy.
>> I've gone ahead and hooked it into the kernel Makefile logic. The way I
>> have it here, doing 'make scripts' ends up compiling 'mdp', after which
>> you must
>> cd scripts/selinux
>> sh install_policy.sh
>> That isn't as nice as being able to do
>> make selinux_install
>> the way David had it, but it avoids mucking with the top-level
>> Makefile. Which is preferred?
>> In any case, this seems like a good thing to have in the kernel
>> tree, to facilitate simple selinux boot tests.
>> Following is David's original patch intro (preserved especially
>> bc it has stats on the generated policies):
>> For those interested in the changes there were only two significant
>> changes. The first is that the iteration through the list of classes
>> used NULL as a sentinel value. The problem with this is that the
>> class_to_string array actually has NULL entries in its table as place
>> holders for the user space object classes.
>> The second change was that it would seem at some point the initial sids
>> table was NULL terminated. This is no longer the case so that iteration
>> has to be done on array length instead of looking for NULL.
>> Some statistics on the policy that it generates:
>> The policy consists of 523 lines which contain no blank lines. Of those
>> 523 lines 453 of them are class, permission, and initial sid
>> definitions. These lines are usually little to no concern to the policy
>> developer since they will not be adding object classes or permissions.
>> Of the remaining 70 lines there is one type, one role, and one user
>> statement. The remaining lines are broken into three portions. The first
>> group are TE allow rules which make up 29 of the remaining lines, the
>> second is assignment of labels to the initial sids which consist of 27
>> lines, and file system labeling statements which are the remaining 11.
>> In addition to the policy.conf generated there is a single file_contexts
>> file containing two lines which labels the entire system with base_t.
>> This policy generates a policy.23 binary that is 7920 bytes.
>> (then a few versions later...):
>> The new policy is 587 lines (stripped of blank lines) with 476 of those
>> lines being the boilerplate that I mentioned last time. The remaining
>> 111 lines have the 3 lines for type, user, and role, 70 lines for the
>> allow rules (one for each object class including user space object
>> classes), 27 lines to assign types to the initial sids, and 11 lines for
>> file system labeling. The policy binary is 9194 bytes.
>> Signed-off-by: Serge Hallyn <firstname.lastname@example.org>
> > [Snip...] > > I'm not sure if I have to sign off on this but just in case. > > Signed-off-by: David Quigley <email@example.com> > > Dave > > > -- > This message was distributed to subscribers of the selinux mailing list. > If you no longer wish to subscribe, send mail to firstname.lastname@example.org with > the words "unsubscribe selinux" without quotes as the message. How easy would it be to go from this dummy policy to a policy that confined only one application? IE If I wanted to pull in the bind policy, what would be needed.
This is a question that often comes up. I don't want anything confined except this one app?
I would figure syslog would be a problem right off, others? -- This message was distributed to subscribers of the selinux mailing list. If you no longer wish to subscribe, send mail to email@example.com with the words "unsubscribe selinux" without quotes as the message.