From rusty at rustcorp.com.au  Sun Dec  2 22:47:02 2018
From: rusty at rustcorp.com.au (Rusty Russell)
Date: Mon, 03 Dec 2018 09:17:02 +1030
Subject: [Lightning-dev] Dual Funding Proposal
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ZmnSCPxj <ZmnSCPxj at protonmail.com> writes:
>> 128-bit seed in
>> open_channel2 could be added, with sorting by SHA(seed | <marshal of
>> input> | <marshal of witness>) and SHA(seed | <marshal of output>)?
>
> `open_channel2` contains a good amount of entropy --- temporary channel ID, various basepoints.
> Would not hashing `open_channel2` to get this `seed` be sufficient?

Good point.  Something we already have to remember would be ideal, so
any of the basepoints would work, and is not exposed onchain.

seed = revocation_basepoint of open_channel2?

Cheers,
Rusty.