We'll properly handle a protocol error due to user input by halting, and
sending the error back to the user.
When a user goes to issue a new update, based on which state we're in,
we'll either kick off the shutdown, or attempt a new offer. This matches
the new spec update where we'll only send `Shutdown` once per
connection.
In this commit, we update the RBF state machine to handle early offer
cases. This can happen if after we send out shutdown (to kick things
off), the remote party sends their offer early. This can also happen if
their outgoing shutdown (to ACK ours) was delayed for w/e reason, and we
get their offer first.
The alternative was to modify the state machine itself, but we feel that
handling this early case is better in line with the Robustness principle.
In this commit, we implement the latest version of the RBF loop as
described in the spec. We remove the self loop back based on sending or
receiving shutdown. Instead, from the ClosePending state, we can trigger
a new loop by sending SendOfferEvent (we bump), or OfferReceivedEvent
(they bump).
We also update the rbf state machine w/ the new close addr logic. This
log ensures that the remote party always sends our current address, and
that if they send a new address, we'll update our view of it, and
counter sign the correct transaction.
We also add a CloseErr state. With this new state, we can ensure that
we're able to properly report errors back to the RPC client, and also
optionally force a reconnection or send a warning to the remote party.
In this commit, we add the state transitions for the new protofsm based
RBF chan closer. The underlying protocol is a new asymmetric co-op close
process, wherein either side can initiate a chan closer, and use their
settled funds to pay for fees within the channel.
In this commit, we add the initial set of states for the new protofsm
based rbf chan closer. A diagram outlining the new states and their
transitions can be found here:
https://gist.github.com/Roasbeef/acc4ff51b9dff127230228a05553cdfe.
Unlike the existing co-op close process, this co-op close can be
restarted at anytime if either side sends a shutdown message. From
there, we'll each obtain a new RBF'd version that can be re-broadcasted.
This commit creates the set of states, along with the environment that
our state machine will use to drive itself forward.
Oliver Gugger