Red Hat Summit21.5. Sources for public keys
During boot, the kernel loads X.509 keys from a set of persistent key stores into the following keyrings:
-
The system keyring (
.builtin_trusted_keys) -
The
.platformkeyring -
The system
.blacklistkeyring
| Source of X.509 keys | User can add keys | UEFI Secure Boot state | Keys loaded during boot |
|---|---|---|---|
| Embedded in kernel | No | - |
|
|
UEFI | Limited | Not enabled | No |
| Enabled |
| ||
|
Embedded in the | No | Not enabled | No |
| Enabled |
| ||
| Machine Owner Key (MOK) list | Yes | Not enabled | No |
| Enabled |
|
.builtin_trusted_keys- A keyring that is built on boot.
- Provides trusted public keys.
-
rootprivileges are required to view the keys.
.platform- A keyring that is built on boot.
- Provides keys from third-party platform providers and custom public keys.
-
rootprivileges are required to view the keys.
.blacklist- A keyring with X.509 keys which have been revoked.
-
A module signed by a key from
.blacklistwill fail authentication even if your public key is in.builtin_trusted_keys. -
rootprivileges are required to view the keys.
- UEFI Secure Boot
db - A signature database.
- Stores keys (hashes) of UEFI applications, UEFI drivers, and boot loaders.
- The keys can be loaded on the machine.
- UEFI Secure Boot
dbx - A revoked signature database.
- Prevents keys from getting loaded.
-
The revoked keys from this database are added to the
.blacklistkeyring.
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