On 04/18/2018 01:12 PM, Eric W. Biederman wrote:
Mimi Zohar <zohar@xxxxxxxxxxxxxxxxxx> writes:not necessarily special case, but they do need to settle on an interface
On Wed, 2018-04-18 at 09:09 -0700, John Johansen wrote:Roughly. My understanding is that you have to have a write to some
On 04/13/2018 09:25 AM, Mimi Zohar wrote:Eric, would you be OK with that?
[Cc'ing John Johansen]I do think this is generally the right approach for LSMs when looking
On Tue, 2018-03-27 at 18:01 -0500, Eric W. Biederman wrote:
[...]
As such I expect the best way to create the ima namespace is by simply
writing to securityfs/imafs. Possibly before the user namespace is
even unshared. That would allow IMA to keep track of things from
before a container is created.
forward to LSM stacking and more LSMs.
My initial thought was to stage IMA namespacing with just IMA-auditwell it depends on what you want to do. It would be possible to have
first, followed by either IMA-measurement or IMA-appraisal. This
would allow us to get the basic IMA namespacing framework working and
defer dealing with the securityfs related namespacing of the IMA
policy and measurement list issues to later.
By tying IMA namespacing to a securityfs ima/unshare file, we would
need to address the securityfs issues first.
a simple file (not a jump link) within securityfs that IMA could use
without having to deal with all the securityfs issues first. However it
does require that securityfs (not necessarily imafs) be visible within
the mount namespace of the task doing the setup.
filesystem to set the ima policy.
I was expecting having to write an "create ima namespace" value
to the filesystem would not be any special effort.
Now it sounds like providing the "create an ima namespace" is going to
be a special case, and that does not sound correct.
that will work for them, and will work with the order they want to land
things. I was just trying to point out that there are fs solutions that
can work without having deal with the full securityfs/imafs namespacing
solution landing first.
While create a file directly in securityfs that lives along side the imafs
dir.
ima_create_ns
ima/
does feel like a special case. It could work
what I was thinking of when I proposed a simple is to do it within the ima
dir, say
ima/create_ns
For now its just a single file but once imafs becomes "virtualized" to a
namespace view, each dir that imafs jumplinks to contains a instance of the
file.
Or they could avoid securityfs/imafs entirely and leverage a file in
procfs
/proc/<pid>/attr/{current,exec,...}
currently those are claimed by the LSMs but new file could be added or
perhaps even better we could lift the some code from the LSM stacking work
to provide an ima specific dir
/proc/<pid>/attr/ima/{current,exec,...}