Create nip-hierarchically-deterministic-authentication.md

[kngako]

Hello,

I have a NIP that will allow users to share temporary xprivs with the nostr clients they use.

This should also allow nostr client services to be authenticated and scale by also having unique xprivs on each server working on behalf of the nostr client service.

https://github.com/kngako/nips/blob/master/nip-hierarchically-deterministic-authentication.md

[fiatjaf]

I thought about this possibility some time ago and asked around if it would work. My very superficial and probably wrong understanding of BIP-32 after that is that you can either use

• non-hardened keys, in which case the knowledge of the xpub plus that of any derived private key is sufficient to compute the xpriv; or
• hardened keys, which the problem above doesn't exist, but then you cannot prove that a given public key is derived from a given xpub.

Or something like that, which makes this technique impossible.

[fiatjaf]

Related: https://github.com/nostr-protocol/nips/issues/103

[staab]

Is anyone still interested in this?