[PATCH v10 5/8] rust: security: add abstraction for secctx

[Alice Ryhl]

On Mon, Sep 16, 2024 at 5:40 PM Casey Schaufler <casey at schaufler-ca.com> wrote:
>
> On 9/15/2024 2:07 PM, Alice Ryhl wrote:
> > On Sun, Sep 15, 2024 at 10:58 PM Kees Cook <kees at kernel.org> wrote:
> >> On Sun, Sep 15, 2024 at 02:31:31PM +0000, Alice Ryhl wrote:
> >>> Add an abstraction for viewing the string representation of a security
> >>> context.
> >> Hm, this may collide with "LSM: Move away from secids" is going to happen.
> >> https://lore.kernel.org/all/20240830003411.16818-1-casey@schaufler-ca.com/
> >>
> >> This series is not yet landed, but in the future, the API changes should
> >> be something like this, though the "lsmblob" name is likely to change to
> >> "lsmprop"?
> >> security_cred_getsecid()   -> security_cred_getlsmblob()
> >> security_secid_to_secctx() -> security_lsmblob_to_secctx()
>
> The referenced patch set does not change security_cred_getsecid()
> nor remove security_secid_to_secctx(). There remain networking interfaces
> that are unlikely to ever be allowed to move away from secids. It will
> be necessary to either retain some of the secid interfaces or introduce
> scaffolding around the lsm_prop structure.
>
> Binder is currently only supported in SELinux, so this isn't a real issue
> today. The BPF LSM could conceivably support binder, but only in cases where
> SELinux isn't enabled. Should there be additional LSMs that support binder
> the hooks would have to be changed to use lsm_prop interfaces, but I have
> not included that *yet*.
>
> > Thanks for the heads up. I'll make sure to look into how this
> > interacts with those changes.
>
> There will be a follow on patch set as well that replaces the LSMs use
> of string/length pairs with a structure. This becomes necessary in cases
> where more than one active LSM uses secids and security contexts. This
> will affect binder.

When are these things expected to land? If this patch series gets
merged in the same kernel cycle as those changes, it'll probably need
special handling.

Alice