How to check if UUID v5 was generated with a specific namespace?

[lucgagan]

Feature description

I've generated UUID with a namespace, and later I want to confirm if that ID was generated using a specific namespace. How do I do that?

Additional information

No response

[broofa]

Take a guess at the name and namespace, generate a new UUID. If you get the same UUID as the one you have, then you guessed right.

To my knowledge that's the only way you can verify the name + namespace for an existing UUID. The hashes used by v3 (MD5) and v5 (SHA1) are non-reversible and the RFC has no provisions for validating names or namespaces from generated IDs. (No checksums, no validation fields of any sort.)