This follows https://github.com/lightningnetwork/lightning-rfc/pull/847.
For anchor_outputs, we pass down a max_feerate to closingd, and set the
fee ceiling to MAX. It uses that to estimate the desired closing fee.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Changelog-EXPERIMENTAL: Anchor output mutual close allow a fee higher than the final commitment transaction (as per lightning-rfc #847)
Based on a commit by @niftynei, but:
- Separated quickclose logic from main loop.
- I made it indep of anchor_outputs, use and option instead.
- Disable if they've specified how to negotiate.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We were actually using the last commit tx's size, since we were
setting it in lightningd. Instead, hand the min and desired feerates
to closingd, and (as it knows the weight of the closing tx), and have
it start negotiation from there.
This can be significantly less when anchor outputs are enabled: for
example in test_closing.py, the commit tx weight is 1124 Sipa, the
close is 672 Sipa!
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Changelog-Changed: Protocol: Use a more accurate fee for mutual close negotiation.
It handles all the cases of retransmission, and in the normal case
retransmits shutdown and immediately returns for us to run closingd.
This is actually far simpler and reduces code duplication.
[ Includes fixup to stop warn_unused_result from Christian ]
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Changelog-Fixed: Protocol: We could get stuck on signature exchange if we needed to retransmit the final revoke_and_ack.
v2 channel open uses a different method to derive the channel_id, so now
we save it to the database so that we dont have to remember how to
derive it for each.
includes a migration for existing channels
Rusty Russell
niftynei