Remove $FreeBSD$: one-line .h pattern

Remove /^\s*\*+\s*\$FreeBSD\$.*$\n/

Move ve_check_hash prototype to libsecureboot-priv.h

Reviewed by: stevek

libsecureboot: allow OpenPGP support to be dormant

Since we can now add OpenPGP trust anchors at runtime,
ensure the latent support is available.

Ensure we do not add duplicate keys to trust store.

Also allow reporting names of trust anchors added/revoked

We only do this for loader and only after initializing trust store.
Thus only changes to initial trust store will be logged.

Reviewed by: stevek
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D20700

libsecureboot: make it easier to customize trust anchors

Avoid making hash self-tests depend on X.509 certs.
Include OpenPGP keys in trust store count.

Reviewed by: stevek
MFC after: 1 week
Sponsored by: Juniper Networks
Differential Revision: https://reviews.freebsd.org/D20208

Create kernel module to parse Veriexec manifest based on envs

The current approach of injecting manifest into mac_veriexec is to
verify the integrity of it in userspace (veriexec (8)) and pass its
entries into kernel using a char device (/dev/veriexec).
This requires verifying root partition integrity in loader,
for example by using memory disk and checking its hash.
Otherwise if rootfs is compromised an attacker could inject their own data.

This patch introduces an option to parse manifest in kernel based on envs.
The loader sets manifest path and digest.
EVENTHANDLER is used to launch the module right after the rootfs is mounted.
It has to be done this way, since one might want to verify integrity of the init file.
This means that manifest is required to be present on the root partition.
Note that the envs have to be set right before boot to make sure that no one can spoof them.

Submitted by: Kornel Duleba <mindal@semihalf.com>
Reviewed by: sjg
Obtained from: Semihalf
Sponsored by: Stormshield
Differential Revision: https://reviews.freebsd.org/D19281

Extend libsecureboot(old libve) to obtain trusted certificates from UEFI and implement revocation

UEFI related headers were copied from edk2.

A new build option "MK_LOADER_EFI_SECUREBOOT" was added to allow
loading of trusted anchors from UEFI.

Certificate revocation support is also introduced.
The forbidden certificates are loaded from dbx variable.
Verification fails in two cases:

There is a direct match between cert in dbx and the one in the chain.
The CA used to sign the chain is found in dbx.
One can also insert a hash of TBS section of a certificate into dbx.
In this case verifications fails only if a direct match with a
certificate in chain is found.

Submitted by: Kornel Duleba <mindal@semihalf.com>
Reviewed by: sjg
Obtained from: Semihalf
Sponsored by: Stormshield
Differential Revision: https://reviews.freebsd.org/D19093

Add libsecureboot

Used by loader and veriexec
Depends on libbearssl

Reviewed by: emaste
Sponsored by: Juniper Networks
Differential Revision: D16335