To make the channel state machine less concerned about the type of
commitment, we nil the local tweak when creating the keyring, depending
on the commitment type.
We abstract away how keys are generated for the different channel types
types (currently tweak(less)).
Intention is that more of the logic that is unique for each commitment
type lives in commitment.go, making the channel state machine oblivious
to the keys and outputs being created on the commitment tx for a given
channel state.
createCommitmentTx would earlier mutate the passed commitment struct
after evaluating the htlc view and calculating the final balances, which
was confusing since the balances are supposed to only be *after*
subtracting fees.
Instead we take the needed parameters as arguments, and return the final
balances, tx and fee to populate the commitment struct in a proper way.
PURE CODE MOVE:
Moving createCommitmentTx, CreateCommitTx, createStateHintObfuscator,
CommitmentKeyRing, DeriveCommitmentKeys, addHTLC, genHtlcScripts
We move the methods and structs to a new file commitment.go in
preparation for defining all the logic that is dependent on the channel
type in this new file.
Instead of passing delays and dustlimits separately, we pass the correct
channel config to CreateCommitTx from the POV of the local party that
owns the commit tx.
To make it more clear which commitment we are actually creating, we
rename variables to denote local and remote, to prepare for the case
when both outputs might be delayed.
Extend lncli with a flag that indicates the intention to send
a spontaneous payment. lncli will generate a preimage/hash combination
and send the preimage as a custom record to the recipient.
This commit adds handling code for the key send custom record. If this
record is present and its hash matches the payment hash, invoice
registry will insert a new invoice into the database "just in time". The
subsequent settle flow is unchanged. The newly inserted invoice is
picked up and settled. Notifications will be broadcast as usual.
This field isn't optional. It was introduced in
5ed31b1030 which was part of release
0.4.0. This release contained breaking database changes, so it is safe
to assume that from there on the field is always populated.
If there would still be empty payment request fields in the wild, users
would also experience issues with ListInvoices. ListInvoices decodes the
payment request.
In this commit, we implement the currently defined transition methods
for the new `FundingStateStep` method. At this point, we're now able to
serve the "responder" of the externally initiated channel funding flow
by being able to register and cancel a funding flow according to its
expected pending channel ID.
In this commit, we update the `OpenChannel` method to observe the new
`funding_shim` field in the main open channel request. If this is
specified, and is a channel point shim, then we'll create a custom
`chanfunding.Assembler` for the wallet to use in place of the regular
funding workflow.
With this commit, the "initiator" of an external funding flow can now
delegate the remainder of the channel funding workflow to lnd.
In this commit, we start to expose some of the new external funding
functionality over the RPC interface.
First, we add a new `funding_shim` field to the regular `OpenChannel`
method. This can be used by a caller to express that certain parameters
of the funding flow have already been negotiated outside the protocol,
and should be used instead. For example, a shim can be provided to use a
particular key for the commitment key (ideally cold) rather than use one
this is generated by the wallet as normal, or signal that signing will
be carried out in an interactive manner (PSBT based).
Next, we add a brand new method: `FundingStateStep`. FundingStateStep is
an advanced funding related call that allows the caller to either
execute some preparatory steps for a funding workflow, or manually
progress a funding workflow. The primary way a funding flow is
identified is via its pending channel ID. As an example, this method can
be used to specify that we're expecting a funding flow for a particular
pending channel ID, for which we need to use specific parameters.
Alternatively, this can be used to interactively drive PSBT signing for
funding for partially complete funding transactions.
The new transition methods (funding state machine modifiers) in this
commit allow a party to register a funding intent that should be used
for a specified incoming pending channel ID. The "responder" to the
external channel flow should use this to prep lnd to be able to handle
the channel flow properly.
This commit adds success mission control
results for all hops along the route in
a mpp timeout and takes no action for
the final hop along the route. This is a
temporary measure to prevent the default
logic from penalizing the final node while
we decide how to penalize mpp timeouts.
This commit adds a getResolutionFailure function
which returns an appropriate wire failure based
on the outcome of a htlc resolution. It also updates
the MissionControlStore test to ensure that lnd
can handle failures which occur due to mpp timeout.
This commit moves handling of invoice not found
errors into NotifyExitHopHtlc and exposes a
resolution result to the calling functions. The
intention of this change is to make calling
functions as naive of the invoice registry's
mechanics as possible.
When NotifyExitHopHtlc is called and an invoice
is not found, calling functions can take action
based on the HtlcResolution's InvoiceNotFound
outcome rather than having to add a special error
check on every call to handle the error.
This commit adds the resolution result obtained
while updating an invoice in the registry to
htlcResolution. The field can be used by calling
functions to determine the outcome of the
update and act appropriately.
