kernel/linux.git/Documentation/admin-guide/LSM/ipe.rst, branch v6.12.80

ipe: allow secondary and platform keyrings to install/update policies

2024-10-17T18:46:10+00:00

The current policy management makes it impossible to use IPE in a general purpose distribution. In such cases the users are not building the kernel, the distribution is, and access to the private key included in the trusted keyring is, for obvious reason, not available. This means that users have no way to enable IPE, since there will be no built-in generic policy, and no access to the key to sign updates validated by the trusted keyring. Just as we do for dm-verity, kernel modules and more, allow the secondary and platform keyrings to also validate policies. This allows users enrolling their own keys in UEFI db or MOK to also sign policies, and enroll them. This makes it sensible to enable IPE in general purpose distributions, as it becomes usable by any user wishing to do so. Keys in these keyrings can already load kernels and kernel modules, so there is no security downgrade. Add a kconfig each, like dm-verity does, but default to enabled if the dependencies are available. Signed-off-by: Luca Boccassi Reviewed-by: Serge Hallyn [FW: fixed some style issues] Signed-off-by: Fan Wu

ipe: also reject policy updates with the same version

2024-10-17T18:38:15+00:00

Currently IPE accepts an update that has the same version as the policy being updated, but it doesn't make it a no-op nor it checks that the old and new policyes are the same. So it is possible to change the content of a policy, without changing its version. This is very confusing from userspace when managing policies. Instead change the update logic to reject updates that have the same version with ESTALE, as that is much clearer and intuitive behaviour. Signed-off-by: Luca Boccassi Reviewed-by: Serge Hallyn Signed-off-by: Fan Wu

documentation: add IPE documentation

2024-08-20T18:03:47+00:00

Add IPE's admin and developer documentation to the kernel tree. Co-developed-by: Fan Wu Signed-off-by: Deven Bowers Signed-off-by: Fan Wu Signed-off-by: Paul Moore