From an original patch by Danish Prakash.

With commit ff22a78d7b52 ("pasta: Don't try to watch namespaces in
procfs with inotify, use timer instead"), if a filesystem-bound
target namespace is passed on the command line, we'll grab a handle
on its parent directory. That commit, however, didn't introduce a
matching AppArmor rule. Add it here.

To access a network namespace procfs entry, we also need a 'ptrace'
rule. See commit 594dce66d3bb ("isolation: keep CAP_SYS_PTRACE when
required") for details as to when we need this -- essentially, it's
about operation with Buildah.

Reported-by: Jörg Sonnenberger <joerg@bec.de>
Link: https://github.com/containers/buildah/issues/5440
Link: https://bugzilla.suse.com/show_bug.cgi?id=1221840
Fixes: ff22a78d7b52 ("pasta: Don't try to watch namespaces in procfs with inotify, use timer instead")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

With Podman's custom networks, pasta will typically need to open the
target network namespace at /run/user/<UID>/containers/networks:
grant access to anything under /run/user/<UID> instead of limiting it
to some subpath.

Note that in this case, Podman will need pasta to write out a PID
file, so we need write access, for similar locations, too.

Reported-by: Jörg Sonnenberger <joerg@bec.de>
Link: https://github.com/containers/buildah/issues/5440
Link: https://bugzilla.suse.com/show_bug.cgi?id=1221840
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

For the policy to work as expected across either AppArmor commit
9d3f8c6cc05d ("parser: fix parsing of source as mount point for
propagation type flags") and commit 300889c3a4b7 ("parser: fix option
flag processing for single conditional rules"), we need one mount
rule with matching mount options as "source" (that is, without
source), and one without mount options and an explicit, empty source.

Link: https://github.com/containers/buildah/issues/5440
Link: https://bugzilla.suse.com/show_bug.cgi?id=1221840
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

The spec file patch by Dan Čermák was originally contributed at:
  https://src.fedoraproject.org/rpms/passt/pull-request/1

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>

Partially equivalent to commit abf5ef6c22d2 ("apparmor: Allow pasta
to remount /proc, access entries under its own copy"): we should
allow pasta to remount /proc. It still works otherwise, but further
UID remapping in nested user namespaces (e.g. pasta in pasta) won't.

Reported-by: Laurent Jacquot <jk@lutty.net>
Link: https://bugs.passt.top/show_bug.cgi?id=79#c3
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

This reverts commit 3fb3f0f7a59498bdea1d199eecfdbae6c608f78f: it was
meant as a patch for Fedora 37 (and no later versions), not something
I should have merged upstream.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

If passt is started with --fd to talk over a pre-opened UNIX domain
socket, we don't really know what label might be associated to it,
but at least for an unconfined_t socket, this bit of policy wouldn't
belong to anywhere else: enable that here.

This is rather loose, of course, but on the other hand passt will
sandbox itself into an empty filesystem, so we're not really adding
much to the attack surface except for what --fd is supposed to do.

Reported-by: Matej Hrica <mhrica@redhat.com>
Link: https://bugzilla.redhat.com/show_bug.cgi?id=2247221
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

With current selinux-policy-37.22-1.fc37.noarch, and presumably any
future update for Fedora 37, the user_namespace class is not
available, so statements using it prevent the policy from being
loaded.

If a class is not defined in the base policy, any related permission
is assumed to be enabled, so we can safely drop those.

Link: https://bugzilla.redhat.com/show_bug.cgi?id=2237996
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

The hard link trick didn't actually fix the issue with SELinux file
contexts properly: as opposed to symbolic links, SELinux now
correctly associates types to the labels that are set -- except that
those labels are now shared, so we can end up (depending on how
rpm(8) extracts the archives) with /usr/bin/passt having a
pasta_exec_t context.

This got rather confusing as running restorecon(8) seemed to fix up
labels -- but that's simply toggling between passt_exec_t and
pasta_exec_t for both links, because each invocation will just "fix"
the file with the mismatching context.

Replace the hard links with two separate builds of the binary, as
suggested by David. The build is reproducible, so we pass "-pasta" in
the VERSION for pasta's build. This is wasteful but better than the
alternative.

Just copying the binary over would otherwise cause issues with
debuginfo packages due to duplicate Build-IDs -- and rpmbuild(8) also
warns about them.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

If pasta and pasta.avx2 are hard links to passt and passt.avx2,
AppArmor will attach their own profiles on execution, and we can
restrict passt's profile to what it actually needs. Note that pasta
needs to access all the resources that passt needs, so the pasta
abstraction still includes passt's one.

I plan to push the adaptation required for the Debian package in
commit 5bb812e79143 ("debian/rules: Override pasta symbolic links
with hard links"), on Salsa. If other distributions need to support
AppArmor profiles they can follow a similar approach.

The profile itself will be installed, there, via dh_apparmor, in a
separate commit, b52557fedcb1 ("debian/rules: Install new pasta
profile using dh_apparmor").

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>