Wraps the engine itself with an AppArmor policy.
This restricts what may be done by applications
we call out to, such as 'xz'.
Significantly, this policy also restricts the policies
to which a container may be spawned into. By default,
users will be able to transition to an unconfined
policy or any policy prefaced with 'docker-'.
Local operators may add new local policies prefaced
with 'docker-' without needing to modify this policy.
Operators choosing to disable privileged containers
will need to modify this policy to remove access
to change_policy to unconfined.
Signed-off-by: Eric Windisch <eric@windisch.us>
By using the 'unconfined' policy for privileged
containers, we have inherited the host's apparmor
policies, which really make no sense in the
context of the container's filesystem.
For instance, policies written against
the paths of binaries such as '/usr/sbin/tcpdump'
can be easily circumvented by moving the binary
within the container filesystem.
Fixes GH#5490
Signed-off-by: Eric Windisch <eric@windisch.us>
The automatic installation of AppArmor policies prevents the
management of custom, site-specific apparmor policies for the
default container profile. Furthermore, this change will allow
a future policy for the engine itself to be written without demanding
the engine be able to arbitrarily create and manage AppArmor policies.
- Add deb package suggests for apparmor.
- Ubuntu postinst use aa-status & fix policy path
- Add the policies to the debian packages.
- Add apparmor tests for writing proc files
Additional restrictions against modifying files in proc
are enforced by AppArmor. Ensure that AppArmor is preventing
access to these files, not simply Docker's configuration of proc.
- Remove /proc/k?mem from AA policy
The path to mem and kmem are in /dev, not /proc
and cannot be restricted successfully through AppArmor.
The device cgroup will need to be sufficient here.
- Load contrib/apparmor during integration tests
Note that this is somewhat dirty because we
cannot restore the host to its original configuration.
However, it should be noted that prior to this patch
series, the Docker daemon itself was loading apparmor
policy from within the tests, so this is no dirtier or
uglier than the status-quo.
Signed-off-by: Eric Windisch <eric@windisch.us>
