Messages in this thread | | | Subject | Re: [RFC PATCH 11/12] certs: Add a secondary system keyring that can be added to dynamically [ver #2] | From | Mimi Zohar <> | Date | Tue, 08 Mar 2016 11:15:00 -0500 |
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On Tue, 2016-03-08 at 15:32 +0000, David Howells wrote: > Mimi Zohar <zohar@linux.vnet.ibm.com> wrote: > > > > The problem boils down to a difficulty in concocting a name that describes a > > > complex situation that may change depending on the configuration. I can make > > > it "restrict_link_by_any_system_trusted" if you'd prefer. > > > > > > That's why I want "system trusted keyrings" to refer to the builtin and the > > > secondary - *and* an extra UEFI keyring if we grow one of those. It's a > > > collection of related keyrings. > > > > Sigh, this is the same discussion we've had for years. > > No, it isn't.
Good!
> > The UEFI keys should not be trusted to validate the certificates being added > > to the IMA keyring. > > A machine-security (e.g. UEFI) keyring will conceivably live in > certs/system_keyring.c and only be enabled if CONFIG_SYSTEM_TRUSTED_KEYRINGS=y > and, say, CONFIG_MACHINE_TRUSTED_KEYRING=y. I didn't say that IMA necessarily > has to use it.
Ok.
> What we need to do is define a set of functions allow IMA to get the > restrictions it wants, depending on configuration. In the code I currently > have, I think we have those: > > restrict_link_reject
Option 1
> restrict_link_by_builtin_trusted
Option 2
> restrict_link_by_system_trusted
By renaming the system keyring to builtin, this is where it becomes unclear what is included by restrict_link_by_system_trusted - builtin and secondary, or builtin, secondary, and UEFI.
> If you really want, I can add a restrict_link_for_ima in there, but I'd rather > not if IMA can use whichever of the above three most suits it. How about: > > restrict_link_reject > restrict_link_by_builtin_trusted > restrict_link_by_builtin_or_secondary_trusted
Option 3 - "restrict_link_by_builtin_or_secondary_trusted" is a bit wordy, but there wouldn't be any confusion.
Mimi
> > Neither should the keys on the secondary keyring, unless specifically IMA > > Kconfig enabled, be used to validate the certificates being added to the IMA > > keyring. > > Yes. > > David >
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