Outdated _DATETIME_ specification

[palant]

Note: I meant this to be a pull request but I cannot quite figure out the toolchain you use to generate all the formats from rfc.md. The tools I try produce a way too verbose diff.

Section 3.1.1 currently claims _DATETIME_ to be in ISO 8601 format. This actually changed from KDBX 3.1 to KDBX 4.0 however. The new format is a base64-encoded 64 bit LE integer representing a number of seconds since 0001-01-01 00:00:00 UTC. There is a corresponding note at the bottom of https://keepass.info/help/kb/kdbx_4.html.

[phoerious]

Good catch, although I think that the behaviour is very inconsistent. Not even sure if this should be part of the XML spec, but it should definitely be mentioned.

[palant]

Not sure what’s inconsistent here. In my test database I can see only one ISO date: _LAST_MODIFIED key stored under <CustomData>. That’s a non-standard entry by KeePassXC. Everything else is base64-encoded dates and only those.

[phoerious]

It's inconsistent that we have two different formats for the XML plaintext and the XML-In-KDBX formats. Also, I don't really see the point of a binary date format for performance reasons. If you are really concerned about that, you should drop the XML serialisation altogether and replace the entire thing with a binary format.

[palant]

Ah, I see. Yes, I was also surprised when I read about performance being the reason for this change. I cannot imagine there being enough dates in a database to justify this change, even if all of them are processed at once.

Question is: is this RFC describing the KDBX format as it currently exists or the format we’d rather have? If it’s the latter, I’d certainly have more suggestions. 😃

[phoerious]

It's entirely descriptive. You can formulate wishes for KDBX5, though.