blockdev: add support for dm-integrity's new UUID naming scheme

[nikita-dubrovskii]

Cryptsetup commit 12eb040 ("Create dm-integrity with CRYPT_SUBDEV prefix.") changed UUID naming scheme for integrity-protected devices:

$ dmsetup info --columns --noheadings -o UUID /dev/dm-2
CRYPT-SUBDEV-ef0561fda2cf4f8eb9fd729f4cd3e0c7-root_dif

Before crytsetup-2.8.0:

$ dmsetup info --columns --noheadings -o UUID /dev/dm-2
CRYPT-INTEGRITY-bec07f15a1c540b0833fcccd6ac2459d-root_dif

This PR updates is_luks_integrity() to recognize both schemes.

https://gitlab.com/cryptsetup/cryptsetup/-/commit/12eb04094304467232348e99df0fbf95074d35b3

[gemini-code-assist]

Summary of Changes

Hello @nikita-dubrovskii, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request enhances the system's ability to correctly identify LUKS integrity-protected devices by adapting to a recent change in cryptsetup's UUID naming convention. It ensures that the blockdev module can seamlessly recognize devices created with both the older and newer dm-integrity UUID formats, preventing potential detection failures.

Highlights

• Compatibility Update: The is_luks_integrity() function has been updated to recognize the new CRYPT-SUBDEV- UUID naming scheme used by dm-integrity devices since cryptsetup-2.8.0. This ensures continued compatibility with newer cryptsetup versions while still supporting the older CRYPT-INTEGRITY- scheme.
• Documentation: A new entry has been added to the release-notes.md file, documenting the support for cryptsetup-2.8.0's UUID naming of dm-integrity devices under 'Internal changes'.

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[gemini-code-assist]

Code Review

This pull request updates the is_luks_integrity function to support a new UUID naming scheme for dm-integrity devices introduced in cryptsetup-2.8.0. The change correctly identifies both the old CRYPT-INTEGRITY- prefix and the new CRYPT-SUBDEV- prefix. The release notes are also updated to reflect this change. My review includes a minor correction for a typo in the release notes and a suggestion to improve maintainability in the Rust code by using constants for the UUID prefixes.

[gemini-code-assist]

Using magic strings like "CRYPT-INTEGRITY-" and "CRYPT-SUBDEV-" can make the code harder to read and maintain. It's a good practice to define them as named constants. This improves clarity and makes it easier to manage these values if they need to be changed or referenced elsewhere in the future.

For example:

const OLD_CRYPT_INTEGRITY_PREFIX: &str = "CRYPT-INTEGRITY-";
const NEW_CRYPT_INTEGRITY_PREFIX: &str = "CRYPT-SUBDEV-";

// ...

Ok(uuid.starts_with(OLD_CRYPT_INTEGRITY_PREFIX) || uuid.starts_with(NEW_CRYPT_INTEGRITY_PREFIX))

[jlebon]

Gemini suggestion SGTM but also fine as is.
Thanks!

[jlebon]

Annnd nice, this is also failing on coreos/fedora-coreos-tracker#1984.