potential preshared-key changes

[Fredrik Strömberg]

Hi! :)

On Sun, Apr 23, 2017 at 9:05 AM,  <crasm at wireguard.1.email.vczf.io> wrote:
> Forgive me in advance if this is a horrible or misinformed idea, but why
> not blake2s the preshared-key with each peer's public key and distribute
> that as a per-peer "preshared" key, mixing it in last? That would reduce
> the risk of key compromise, since each peer would have a unique key and
> the real key is not copied to each peer.
>
If I understand you correctly you're suggesting:

1. Peer PSK = BLAKE2S( "Real PSK" + "Peer's static pubkey" )
2. Mix in the peer's PSK the same way Jason suggests

In practice this is equivalent to the discussed change, and "Peer PSK"
would be the real key, for that peer.

Regards,
Fredrik Stromberg