Add trustee-client - a simple client for Trustee

[uril]

Gather evidence, attest and get secrets from Trustee

Currently it simply uses AA's kbs_protocol client and attesters. If needed, it can be enhanced later.

[fitzthum]

Looks good. One comment.

Also, I am not sure the config file is really necessary. it seems a little cumbersome to have to specify the KBS URL in the config file rather than just putting it in the command line, but it's not a big deal.

Btw, it's interesting that we're in the guest-components repo. I think that's fine and maybe having some kind of client in both guest-components and trustee repos will help us decouple the tests a little bit.

[fitzthum]

I think this name might be too general. This tool only exercises a subset of the Trustee APIs. Btw see this proposal which might end up with a similar name.

Maybe this could be called cc-kbc-resource-getter or trustee-resource-getter or trustee-resource-client or something else

[uril]

Thanks, I'll take a look at that proposal and think of names.

[uril]

Thanks @fitzthum
I can put the Trustee URL + Certificate in the command line.
If needed a configuration file can be added later.
I noticed that AA and CDH each use a configuration file so I added it here too.

[ChengyuZhu6]

Good job. While this PR functions similarly to a kbs-client. I agree with Tobin's comment that it would be better to move it to the trustee repo if the client is focused on expanding the kbs-client

[Xynnn007]

Nice work. I noticed that the sub-crate aims to implement a binary for dep kbs_protocol. Probably we could make it a binary of kbs_protocol instead of a separate crate. Example for this

[Xynnn007]

Btw, it's interesting that we're in the guest-components repo. I think that's fine and maybe having some kind of client in both guest-components and trustee repos will help us decouple the tests a little bit.

The server (trustee) and client (guest-components) codes are in two repos. If we want to have some test for compability of the two repo, it would always require us to pull the other's code/image/... in another repo

[uril]

@ChengyuZhu6 @Xynnn007 thanks for looking.

The idea is to have a simple program in guest-components repository that can get resources from Trustee.

I thought of adding it as a binary under kbs_protocol, but if more features are added later would it stay under kbs_protocol or move ?

[Xynnn007]

I thought of adding it as a binary under kbs_protocol, but if more features are added later would it stay under kbs_protocol or move ?

We can see the concrete situation then. Up to now, it seems that we can keep the feature aligning with kbs_protocol's.