Previously, we were requiring any `UPDATE` onion errors to include
a `channel_update`, as the spec mandates[1]. If we see an onion
error which is missing one we treat it as a misbehaving node that
isn't behaving according to the spec and simply remove the node.
Sadly, it appears at least some versions of CLN are such nodes, and
opt to not include `channel_update` at all if they're returning a
`temporary_channel_failure`. This causes us to completely remove
CLN nodes from our graph after they fail to forward our HTLC.
While CLN is violating the spec here, there's not a lot of reason
to not allow it, so we go ahead and do so here, treating it simply
as any other failure by letting the scorer handle it.
[1] The spec says `Please note that the channel_update field is
mandatory in messages whose failure_code includes the UPDATE flag`
however doesn't repeat it in the requirements section so its not
crazy that someone missed it when implementing.
In a synchronous `BackgroundProcessor`, the exit is done by setting
an atomic flag, which is most likely to happen while we're asleep.
Thus, we previously checked for the exit condition after the sleep
(and after we persisted the `ChannelManager`, if required, though
this is no longer required and dates back to when we didn't do a
re-persist after breaking out of the main loop).
For an async `background-processor`, this is also fine, however
because of the relatively longer sleep time, if the exit flag is
set via a sleep check returning true during event processing, we
may end up delaying exit rather substantially.
In order to avoid this, we simply check for the exit condition both
before and immediately after the sleep in `background-processor`.
While these transactions were still valid, we incorrectly assumed that
they would propagate with a locktime of `current_height + 1`, when in
reality, only those with a locktime strictly lower than the next height
in the chain are allowed to enter the mempool.
In a future commit, we plan to correctly enforce that the spending
transaction has a valid locktime relative to the chain for the node
broascasting it in `TestBroadcaster::broadcast_transaction` to. We catch
up these test node instances to their expected height, such that we do
not fail said enforcement.
The `height` argument passed to `OnchainTxHandler::block_disconnected`
represents the height being disconnected, and not the current height.
Due to the incorrect assumption, we'd generate a claim with a locktime
in the future.
Ultimately, we shouldn't be generating claims within
`block_disconnected`. Rather, we should retry the claim at a later block
height, since the bitcoin blockchain does not ever roll back without
connecting a new block. Addressing this is left for future work.
This attempts to rebroadcast/fee-bump each pending claim a monitor is
tracking for a force-closed channel. This is crucial in preventing
certain classes of pinning attacks and ensures reliability if
broadcasting fails. For implementations of `FeeEstimator` that also
support mempool fee estimation, we may broadcast a fee-bumped claim
instead, ensuring we can also react to mempool fee spikes between
blocks.
In the next commit, we plan to extend the `OnchainTxHandler` to retry
pending claims on a timer. This timer may fire with much more frequency
than incoming blocks, so we want to avoid manually bumping feerates
(currently by 25%) each time our fee estimator provides a lower feerate
than before.
It currently reads "disconnected from peer which hasn't completed
handshake due to ping timeout", which is confusing.
Instead, it will now read "disconnected from peer which hasn't
completed handshake due to ping/handshake timeout"
Unfortunately, the RAII types used by `RwLock` are not `Send`, which is
why they can't be held over `await` boundaries. In order to allow
asynchronous events processing in multi-threaded environments, we here
allow to process events without holding the `total_consistency_lock`.
We very regularly receive confusion over the super generic
"Peer sent invalid data or we decided to disconnect due to a
protocol error" message, which doesn't say very much. Usually, we
end up disconnecting because we have a duplicate connection with a
peer, which doesn't merit such a scary message.
Instead, here we clarify the error message to just refer to the
fact that we're disconnecting, and note that its usually a dup
connection in a parenthetical.
To match the local signatures found in test vectors, we must make sure
we don't use any additional randomess when generating signatures, as
we'll arrive at a different signature otherwise.
Previously, our local signatures would always be deterministic, whether
we'd grind for low R value signatures or not. For peers supporting
SegWit, Bitcoin Core will generally use a transaction's witness-txid, as
opposed to its txid, to advertise transactions. Therefore, to ensure a
transaction has the best chance to propagate across node mempools in the
network, each of its broadcast attempts should have a unique/distinct
witness-txid, which we can achieve by introducing random nonce data when
generating local signatures, such that they are no longer deterministic.
This allows the `InMemorySigner` to produce its own randomness, which we
plan to use when generating signatures in future work.
We can no longer derive `Clone` due to the `AtomicCounter`, so we opt to
implement it manually.
