[Cc'ing linux-integrity] On Wed, 2021-01-27 at 11:46 +0000, David Howells wrote: > Jarkko Sakkinen <jarkko@xxxxxxxxxx> wrote: > > > > I suppose a user space tool could be created. But wouldn’t what is > > > currently done in the kernel in this area need to be removed? > > > > Right. I don't think this was a great idea in the first place to > > do to the kernel but since it exists, I guess the patch does make > > sense. > > This information needs to be loaded from the UEFI tables before the system > starts loading any kernel modules or running any programs (if we do > verification of such, which I think IMA can do). There needs to a clear distinction between the pre-boot and post-boot keys. UEFI has its own trust model, which should be limited to UEFI. The .platform keyring was upstreamed and limited to verifying the kexec kernel image. Any other usage of the .platform keyring keys is abusing its intended purpose. The cover letter says, "Anytime the .platform keyring is used, the keys in the .blacklist keyring are referenced, if a matching key is found, the key will be rejected." I don't have a problem with loading the UEFI X509 dbx entries as long as its usage is limited to verifying the kexec kernel image. Mimi
