In this commit, we convert the `JusticeKit` struct to an interface.
Then, we add two implementations of that interface:
1) The `legacyJusticeKit` which implements all the methods of
`JusticeKit`
2) The `anchorJusticKit` which wraps the `legacyJusticeKit` and just
re-implements the `ToRemoteOutputSpendInfo` method since.
In this commit a new enum, CommitmentType, is introduced and initially
there are 3 CommitmentTypes: Legacy, LegacyTweakless and Anchor.
Then, various methods are added to `CommitmentType`. This allows us to
remove a bunch of "if-else" chains from the `wtclient` and `lookout`
code. This will also make things easier to extend when a new commitment
type (like Taproot) is added.
In this commit, we update the Sig type to support ECDSA and schnorr
signatures. We need to do this as the HTLC signatures will become
schnorr sigs for taproot channels. The current spec draft opts to
overload this field since both the sigs are actually 64 bytes in length.
The only consideration with this move is that callers need to "coerce" a
sig to the proper type if they need schnorr signatures.
In this commit, we modify the watch tower to use P2TR addrs for just
about anything sweep related.
One eye sore in this diff are the changes to
`backup_task_internal_test.go`. All the values are hard coded, and now
either differ by a value of 48, or needed to be modified to account for
the new assumptions propagated to rewards values and fees.
This commit was previously split into the following parts to ease
review:
- 2d746f68: replace imports
- 4008f0fd: use ecdsa.Signature
- 849e33d1: remove btcec.S256()
- b8f6ebbd: use v2 library correctly
- fa80bca9: bump go modules
This commit introduces a new test case that asserts all of the witness
size constants currently in the codebase. We also reintroduce the
AcceptedHtlcSuccessWitnessSize and OfferedHtlcTimeoutWitnessSize
constants that were recently removed for the sake of completeness.
In asserting the witnes sizes, there were three uncovered discrepancies:
* OfferedHtlcSuccessWitnessSize overestimated by about 30% because it
included an extra signature in the calculation.
* ToLocalPenaltyWitnessSize was underestimated by one byte, because it
was missing the length byte for the OP_TRUE. This has implications
the watchtower protocol since the client and server are assumed to
share the same weight estimates used for signing. This commit keeps
the current behavior, with the intention of rolling out negotiation
for which weight estimate to use for a given session.
* AcceptedHtlcScriptSize was underestimated by one byte because it was
missing a length byte for the value 32 pushed on the stack when
asserting the preimage's length. This affects all AcceptedHtlc*
witness sizes.
In this commit, we update the tower+link logic to tag a commitment as
the new (tweakless) format if it applies. In order to do this, the
BackupTask method has gained an additional parameter to indicate the
type of commitment that we're attempting to upload. This new tweakless
bool is then threaded through all the way to back up task creation to
ensure that we make the proper input.Input.
Finally, we've added a new test case for each existing test case to test
each case w/ and w/o the tweakless modifier.
This commit changes when the sweep pkscript
is assigned in the construction of the justice
transaction. Currently, the sweep pkscript is
assigned when the task is bound to a session.
However, we will moving to an assignment where
a unique sweep pkscript is used per channel to
prevent address inflation. Hence, this commit
makes the sweep pkscript a state dependent
variable, since it can be known at the time the
channel id is assigned.
