Hi John, On Thu, 2017-05-25 at 00:36 -0700, John Johansen wrote: > On 05/24/2017 01:12 PM, Mimi Zohar wrote: > > On Thu, 2017-05-11 at 10:59 -0300, Guilherme Magalhaes wrote: > >> Creating the namespace securityfs file under ima folder. When a mount > >> namespace id is written to the namespace file, a new folder is created and > >> with a policy file for that specified namespace. Then, user defined policy > >> for namespaces may be set by writing rules to this namespace policy file. > >> With this interface, there is no need to give visibility for the securityfs > >> inside mount namespaces or containers in userspace. > >> > >> Signed-off-by: Guilherme Magalhaes <guilherme.magalhaes@xxxxxxx> > > > > The design needs to be flexible enough for different types of > > containers, not just for when the orchestration layer provides the > > policy. With this design, the container owner has no control over the > > policy. > > > > One option is that we bind mount the securityfs/policy, so that root > > in the container will be allowed to read/write the policy. At some > > point, we might connect a vTPM to the container so that the container > > owner would be able to get a quote. For now even without a vTPM, the > > same mechanism would allow root within the container to read the > > measurement list. > > > I haven't looked at this enough yet on IMAs end, but another possible solution > is using a symlink and a magic jump_link similar to what nsfs is doing. > > The patch series I posted out a couple of weeks ago > [RFC][Patch 0/3] securityfs: add the ability to support symlinks > > adds symlink support to securityfs, and then patch 3/3 cribs from nsfs > updating apparmorfs to use jump_link to "virtualize" the apparmor policy > directory. This avoids needing to have the bind mount. > > I'll break the patch out more and repost so its easier to see if this > approach might work for IMA. Sorry, I've been meaning to take a look at your patches, but just haven't gotten to it yet. This approach sounds really promising. thanks, Mimi