Per-object encryption (Re: Git Merge contributor summit notes)

[Jonathan Nieder <jrnieder@gmail.com>]

Hi Ævar,

Ævar Arnfjörð Bjarmason wrote:

> It occurred to me recently that once we have such a layer it could be
> (ab)used with some relatively minor changes to do any arbitrary
> local-to-remote object content translation, unless I've missed something
> (but I just re-read hash-function-transition.txt now...).
>
> E.g. having a SHA-1 (or NewHash) local repo, but interfacing with a
> remote server so that you upload a GPG encrypted version of all your
> blobs, and have your trees reference those blobs.

Interesting!

To be clear, this would only work with deterministic encryption.
Normal GPG encryption would not have the round-tripping properties
required by the design.

If I understand correctly, it also requires both sides of the
connection to have access to the encryption key.  Otherwise they
cannot perform ordinary operations like revision walks.  So I'm not
seeing a huge advantage over ordinary transport-layer encryption.

That said, it's an interesting idea --- thanks for that.  I'm changing
the subject line since otherwise there's no way I'll find this again. :)

Jonathan