Hi All, I just finished writing a (very) rough draft of the Funding Timeout Recovery proposal (a.k.a. "So long, and thanks for all the sigs"). You can find the full proposal here [1].
The proposal details how the fundee can assist the funder quickly recover a botched funding. This is an alternative to using the pre-signed commitment transaction, which likely overestimates the feerate, and also locks the funder's funds with a timeout since it is a unilateral close. The trick is to have the fundee sign a blank check with the funding_privkey, used to setup the 2-of-2, and using `sighash_none` to make the signature independent from the outputs. The funder can then use that signature to create a close transaction however she wants, including adjustable feerates, and any desired outputs. In addition it also includes a recovery mechanism for malleated funding transactions, which can happen from time to time, if there are non-segwit inputs, or if the funding transaction is edited externally to the lightning node prior to broadcasting it. This extension is however optional. There are a couple of open questions at the bottom, and I would be very interested in everyone's opinion on the safety. I think we're ok due to the funding_privkey = channel mapping, but I'm open to further analysis. Since this is rather short-notice for today's spec meeting I'll probably add it to the agenda for next time instead, to give everybody time to familiarize themselves with the proposal, before delving into details :-) Cheers, Christian [1] https://github.com/lightningnetwork/lightning-rfc/pull/854 _______________________________________________ Lightning-dev mailing list Lightning-dev@lists.linuxfoundation.org https://lists.linuxfoundation.org/mailman/listinfo/lightning-dev