Although this new check is unreachable right now, it helps prevent potential
future errors where we incorrectly fail blinded HTLCs with an unblinded error.
If a blinded HTLC errors when added to a Channel, such as if the recipient has
already sent a shutdown message, they should malformed-fail backwards with
error code INVALID_ONION_BLINDING and a zeroed out onion hash per BOLT 4.
If a blinded HTLC does not satisfy the receiver's requirements, e.g. bad CLTV
or amount, they should malformed-fail backwards with error code
INVALID_ONION_BLINDING and a zeroed out onion hash per BOLt 4.
If a recipient behind a multihop blinded path fails to decode their onion
payload, they should fail backwards with error code INVALID_ONION_BLINDING and
a zeroed out onion hash per BOLT 4.
And use it in the multihop blinded path receive failure test. Will be used in
the next commit to test receiving an invalid blinded final onion payload.
We can't use the existing get_route test util here because blinded payments
rely on the sender adding a random shadow CLTV offset to the final hop; without
this the payment will be failed with cltv-expiry-too-soon.
If a blinded recipient to a multihop blinded path needs to fail back a
malformed HTLC, they should use error code INVALID_ONION_BLINDING and a zeroed
out onion hash per BOLT 4.
If an HTLC fails after its RAA is processed, it is failed back with
ChannelManager::fail_htlc_backwards_internal. This method will now correctly
inform the channel that this HTLC is blinded and to construct an
update_malformed message accordingly.
Useful for failing blinded payments back with malformed, and will also be
useful in the future when we move onion decoding into
process_pending_htlc_forwards, after which Channel::fail_htlc will be used for
all malformed htlcs.
Currently it returns only update_fail, but we'll want it to be able to return
update_malformed as well in upcoming commits. We'll use this for correctly
failing blinded received HTLCs backwards with malformed and
invalid_onion_blinding error per BOLT 4.
For context, blinded HTLCs where we are not the intro node must always be
failed back with malformed and invalid_onion_blinding error per BOLT 4.
Prior to supporting blinded payments, the only way for an update_malformed to
be returned from Channel was if an onion was actually found to be malformed
during initial update_add processing. This meant that any malformed HTLCs would
never live in the holding cell but instead would be returned directly upon
initial RAA processing.
Now, we need to be able to store these HTLCs in the holding cell because the
HTLC failure necessitating an update_malformed may come long after the RAA is
initially processed, and we may not be a state to send the update_malformed
message at that time.
Therefore, add a new holding cell HTLC variant for blinded non-intro node
HTLCs, which will signal to Channel to fail with malformed and the correct
error code.
Will be used in the next commit(s) to let us know to fail blinded received
HTLCs backwards with the malformed and invalid_onion_blinding error per BOLT 4.
When a peer is connected, OnionMessenger tracks it only if it supports
onion messages. On disconnect, we debug_assert that the peer was in a
state ConnectedPeer, failing when it is in the PendingConnection state.
However, we were mistakenly asserting for peers that we were not
tracking (i.e., that don't support onion messages). Relax the check to
not fail on the latter.
Currently, our holder commitment broadcast only goes through the
`OnchainTxHandler` for anchor outputs channels because we can actually
bump the commitment transaction fees with it. For non-anchor outputs
channels, we would just broadcast once directly via the
`ChannelForceClosed` monitor update, without going through the
`OnchainTxHandler`.
As we add support for async signing, we need to be tolerable to signing
failures. A signing failure of our holder commitment will currently
panic, but once the panic is removed, we must be able to retry signing
once the signer is available. We can easily achieve this via the
existing `OnchainTxHandler::rebroadcast_pending_claims`, but this
requires that we first queue our holder commitment as a claim. This
commit ensures we do so everywhere we need to broadcast a holder
commitment transaction, regardless of the channel type.
Co-authored-by: Rachel Malonson <rachel@lightspark.com>
Once a commitment transaction is broadcast/confirms, we may need to
claim some of the HTLCs in it. These claims are sent as requests to the
`OnchainTxHandler`, which will bump their feerate as they remain
unconfirmed. When said commitment transaction becomes unconfirmed
though, and another commitment confirms instead, i.e., a reorg happens,
the `OnchainTxHandler` doesn't have any insight into whether these
claims are still valid or not, so it continues attempting to claim the
HTLCs from the previous commitment (now unconfirmed) forever, along with
the HTLCs from the newly confirmed commitment.
Implement the Display trait for Outpoint and utilize it in the codebase for monitoring outpoints.
Additionally, add log tracing for best_block_update and confirmed transactions.
solves #2348
Ensure that if we call construct_onion_packet and friends where payloads are
too large for the allotted packet length, we'll fail to construct. Previously,
senders would happily construct invalid packets by array-shifting the final
node's HMAC out of the packet when adding an intermediate onion layer, causing
the receiver to error with "final payload provided for us as an intermediate
node."
We previously assumed that the final node's payload would be ~93 bytes, and had
code to ensure that the filler encoded after that payload is not all 0s. Now
with custom TLVs and metadata supported, the final node's payload may take up
the entire onion packet, so we can't assume that there are 64 bytes of filler
to check.
`RouteGraphNode` currently recalculates scores in its `Ord`
implementation, wasting time while sorting the main Dijkstra's
heap.
Further, some time ago, when implementing the `htlc_maximum_msat`
amount reduction while walking the graph, we added
`PathBuildingHop::was_processed`, looking up the source node in
`dist` each time we pop'ed an element off of the binary heap.
As a result, we now have a reference to our `PathBuildingHop` when
processing a best-node's channels, leading to several fields in
`RouteGraphNode` being entirely redundant.
Here we drop those fields, but add a pre-calculated score field,
as well as force a suboptimal `RouteGraphNode` layout, retaining
its existing 64 byte size.
Without the suboptimal layout, performance is very mixed, but with
it performance is mostly improved, by around 10% in most tests.
Given `PathBuildingHop` is now an even multiple of cache lines, we
can pick which fields "fall off" the cache line we have visible
when dealing with hops, which we do here.
We'd previously aggressively cached elements in the
`PathBuildingHop` struct (and its sub-structs), which resulted in a
rather bloated size. This implied cache misses as we read from and
write to multiple cache lines during processing of a single
channel.
Here, we reduce caching in `DirectedChannelInfo`, fitting the
`(NodeId, PathBuildingHop)` tuple in exactly 128 bytes. While this
should fit in a single cache line, it sadly does not generally lie
in only two lines, as glibc returns large buffers from `malloc`
which are very well aligned, plus 16 bytes (for its own allocation
tracking). Thus, we try to avoid reading from the last 16 bytes of
a `PathBuildingHop`, but luckily that isn't super hard.
Note that here we make accessing
`DirectedChannelInfo::effective_capacity` somewhat slower, but
that's okay as its only ever done once per `DirectedChannelInfo`
anyway.
While our routing benchmarks are quite noisy, this appears to
result in between a 5% and 15% performance improvement in the
probabilistic scoring benchmarks.
This avoids bloating `CandidateRouteHop` with a full 33-byte
node_id (and avoids repeated public key serialization when we do
multiple pathfinding passes).
`TestRouter` tries to make scoring calls that mimic what an actual
router would do, but the changes in f0ecc3ec73
failed to make scoring calls for private hints or if we take a
public hop for the last hop.
This fixes those regressions, though no tests currently depend on
this behavior.
