From rusty at rustcorp.com.au  Tue Mar  8 06:02:14 2016
From: rusty at rustcorp.com.au (Rusty Russell)
Date: Tue, 08 Mar 2016 16:32:14 +1030
Subject: [Lightning-dev] Backward deterministic R Value
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Nicolas Dorier <nicolas.dorier at gmail.com> writes:
> Great, indeed we had same idea, I don't see how it solve the hashes in
> advance.
> As Alice knows
>
> H(1000000) = <random secret seed>).
>
> If she need the hash to the first commitment she need to hash the random secret
> seed 1000000 times. I think it is exactly the same problem as it is the exact
> same idea said differently.

See:

        https://github.com/rustyrussell/ccan/tree/master/ccan/crypto/shachain

Cheers,
Rusty.