Show keygrips

[orhun]

Discussed in #48

^{Originally posted by dievilz October 12, 2022}
I would love to see the keygrips inside the TUI. That way, I think this program would be even more efficient than already is, at least for me 🤘🏻. And include the respective setting in the config. file too.
I don't think this feature is implemented and I don't know if it is out of scope, but still I'll make the request 😅.
I would love to contribute and make a pull request but sadly I know nothing about Rust :c

[bsodmike]

I'll try picking this up soon :)

[orhun]

Hey @bsodmike! Are you still interested in working on this? I'm happy to guide with the implementation 🐻

[bsodmike]

Hey @bsodmike! Are you still interested in working on this? I'm happy to guide with the implementation 🐻

Hey, sure, please let me know what you have planned :)

[orhun]

Apparently a keygrip is:

This term is used by GnuPG to describe a 20 byte hash value used to identify a certain key without referencing to a concrete protocol. It is used internally to access a private key. Usually it is shown and entered as a 40 character hexadecimal formatted string.

The key grip is (as a first approximation) a hash of the public key material. This is different from the fingerprint, which is a hash of the public key material and some meta-data (in particular, the packet's version, and the key's creation time). This means that if two keys have the same public key material, but different meta-data, then they will have different fingerprints, but the same key grip. As I understand it, the key grip is a gpg invention, which has to do with how gpg-agent works. There's no standard, and no other OpenPGP implementation really uses it.

You can see an example here:

$ gpg -k --with-keygrip

pub   rsa4096 2023-09-28 [SC]
      7545E677A4449CD72A2E3F71930FCF192DECE98B
      Keygrip = FF886AD832FAC91A5AF498434C2DF0D3F8730E5A
uid           [ultimate] daktilo <[email protected]>
sub   rsa4096 2023-09-28 [E]
      Keygrip = 5A16A03CAF1FDE48154F8FF7D9767C48F07A93F4

We can access these values via Subkey::keygrip function in Rust.

So the question is how should we display them?

Well, key fingerprint and keygrip has the same length so we can add a new command (e.g. keygrip) to show keygrips instead. Or we can show it in the 2nd detail level, somewhere.

You need to play around a bit to find out which one looks better :)