Let plugins know when a channel open has failed.
We need to notify accepters now too, so we remove the check on who's
funding the channel before sending the 'failed' message from
dualopend->master.
We already know what the channel id is, we should go ahead and pass it
on to any listening plugins -- this makes clean up easier/possible
if a open fails early on and we've got reserved utxos.
There's a case where a dropped funding_locked will result in the peer
moving onto channeld, while we stay in dualopend. As we haven't
received their funding_locked, we retransmit tx_sigs, which channeld
will need to handle.
With the patch the peer drops it on the floor; the peer will resend
funding_locked on reconnect, which will correctly advance us to
channeld and CHANNELD_NORMAL
Prior to this, all reconnect logic lived in channeld. If you
disconnected before we finished building a funding transaction, that was
no big deal. Now, however, we're waiting for the funding to lock in in
dualopend, instead of handing straight to channeld to wait.
So we need a way to restart dualopend.
We were incorrectly saving the *remote's* commitment transaction as the
'last_tx' for a peer, not our own local one.
When we applied the 'remote_commit_sig' to it, it would fail since the
remote's signature doesn't validate for their commitment transaction.
This will make it possible to do RBF, since we can re-start the opening
process in dualopend while waiting for lock-in.
Note the new channel states are being used, DUALOPEND_INIT and
DUALOPEND_AWAITING_LOCKIN, to differentiate from openingd/channeld opens
We let the plugin decide what feerate to accept/whether or not to add
funds to the open. To aid this decision, we also send the plugin what we
(c-lightning) currently have as our max and min acceptable feerates.
We also now use these as our default for max/min acceptable feerate
range when sending an openchannel offer to a peer.
In the future, it might be a good idea to make these more easily
changeable, either via a config setting (?) or a command param.
Note that check-whitespace and check-bolt already do this, so we
can eliminate redundant lines in common/Makefile and bitcoin/Makefile.
We also include the plugin headers in ALL_C_HEADERS so they get
checked.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This is handy/necessary for getting multifundchannel to work, as we need
to know what output to tell all the other peers about.
Changelog-Added: Experimental!! JSON-RPC: openchannel_init returns a field `funding_serial` that indicates the serial_id of the funding output in the provided PSBT
`check_balances` had a weird interface because it was meant to be able
to be used at any 'intermediate' point to verify that a single side had
a valid inputs/output balance.
This was worse than useless. Now it just straight checks for both sides'
balances are correct and that both sides pay their fees. Called after
transaction is constructed.
There's a few structs/wire calls that only exist under experimental features.
These were in a common file that was shared/used a bunch of places but
this causes problems. Here we move one of the problematic methods back
into `openingd`, as it's only used locally and then isolate the
references to the `witness_stack` in a new `common/psbt_internal` file.
This lets us remove the iff EXP_FEATURES inclusion switches in most of
the Makefiles.
Rusty pointed out that having an empty channel_id is suboptimal; adding
another call is probably the right idea rather than re-using an existing
one.
Suggested-By: @rustyrussell
There are 3 commands for opening a channel with dualfunding.
`openchannel_init` is the first of these.
It initializes the open-channel dialog, and stops once we've run out of
updates (input/outputs) to send to the peer.
niftynei
Rusty Russell