** Description changed:

  [ Impact ]
  
   * Every OVMF/AAVMF virtual machine with Secure Boot enabled is
  impacted.
  
   * VM variable stores are snapshotted at creation time. Existing VMs only
     have Microsoft's 2011 Secure Boot CAs in their KEK and db. These CAs
     expire in 2026 and Microsoft is transitioning to signing exclusively
     with 2023 replacements. Without the 2023 CAs, existing VMs will be
     unable to verify future shim, GRUB, and kernel updates.
  
   * On physical hardware, db and KEK updates are deployed via fwupd using
     authenticated variable writes signed by the appropriate keys. This is
     not possible for OVMF/AAVMF because the PK private key was intentionally
     destroyed at variable template generation time.
  
   * A DXE driver (FirmwareSecvarUpdater) is added to the firmware CODE
     volume. It runs at boot, checks for 2011 CAs without their 2023
     replacements, and appends the missing certificates using EDK2's Custom
     Mode mechanism. A version variable prevents re-running on subsequent
     boots and allows users to remove the added certificates if desired.
  
  [ Test Plan ]
  
   * Build-time and autopkgtest integration tests are included:
  
     1. Boot a VM with only 2011 CAs enrolled, verify all 2023 CAs are
        appended to KEK and db.
  
     2. After the driver has run, strip the 2023 CAs and reboot. Verify
        the version guard prevents re-adding them.
  
     3. Same as (1) for AAVMF (aarch64).
  
  [ Where problems could occur ]
  
   * If the driver encounters an error (e.g. variable store full), it fails
     gracefully without preventing boot and retries on the next boot.
  
   * The driver only acts on variable stores containing the expected 2011
     CAs.
  
   * If a user removes the 2023 CAs after the driver has run, the version
     guard ensures they are not re-added.
  
  [ Other Info ]
  
   * Certificate mappings:
     - KEK: MS KEK CA 2011 -> MS KEK 2K CA 2023
     - db: Windows Production PCA 2011 -> Windows UEFI CA 2023
     - db: MS UEFI CA 2011 -> MS UEFI CA 2023 + MS Option ROM CA 2023
  
   * The driver is added to all virtual platform builds with Secure Boot
     support. Future certificate rotations require only adding rows to the
     update rules table and bumping the version constant.
+ 
+  * "Reset Secure Boot Keys" works exactly the same as it did before this 
change,
+    it clears all Secure Boot keys and brings the system to Setup Mode.

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https://bugs.launchpad.net/bugs/2146560

Title:
  [FFe + SRU] edk2: Introduce FirmwareSecvarUpdater for MS 2023 CA
  rollout

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