These are useful, but we previously couldn't use them due to our
MSRV. Now that we can, we should use them, so we expose them via
our normal debug_sync wrappers.
The `lightning-net-tokio` crate-level example contained a carryover
from when it was the primary notifier of the background processor
and now just shows an "example" of creating a method to call
another method with the same parameters and then do event
processing (which doesn't make sense, the BP should do that).
Instead, the examples are simply removed and the documentation is
tweaked to include recent changes.
As `futures` apparently makes no guarantees on MSRVs even in patch
releases we really can't rely on it at all, and while it currently
has an acceptable MSRV without the macros feature, its best to just
remove it wholesale.
Luckily, removing it is relatively trivial, even if it requires
the most trivial of unsafe tags.
`futures` recently broke our MSRV by bumping the `syn` major
version in a patch release. This makes it impractical for us to
use, instead here we replace the usage of its `select_biased` macro
with a trivial enum.
Given its simplicity we likely should have done this without ever
taking the dependency.
In general, only one request will be in flight at a time in
`lightning-block-sync`. Ideally we'd only have one connection, but
without using the `futures` mutex type.
Here we solve this narrowly for the one-request-at-a-time case by
caching the connection and takeing the connection out of the cache
while we work on it.
Some how I'd understood that `futures` had reasonable MSRV
guarantees (e.g. at least Debian stable), but apparently that isn't
actually the case, as they bumped it to upgrade to syn (with
apparently no actual features or bugfixes added as a result?) with
no minor version bump or any available alternative (unlike Tokio,
which does LTS releases).
Luckily its relatively easy to just drop the `futures` dependency -
it means a new connection for each request, which is annoying, but
certainly not the end of the world, and its easier than trying to
deal with pinning `futures`.
See https://github.com/rust-lang/futures-rs/pull/2733
As long as the lock order on such locks is still valid, we should allow
them regardless of whether they were constructed at the same location or
not. Note that we can only really enforce this if we require one lock
call per line, or if we have access to symbol columns (as we do on Linux
and macOS). We opt for a smaller patch by relying on the latter.
This was previously triggered by some recent test changes to
`test_manager_serialize_deserialize_inconsistent_monitor`. When the
test ends and a node is dropped causing us to persist each, we'd detect
a possible lockorder violation deadlock across three different `Mutex`
instances that are held at the same location when serializing our
`per_peer_states` in `ChannelManager::write`.
The presumed lockorder violation happens because the first `Mutex` held
shares the same construction location with the third one, while the
second `Mutex` has a different construction location. When we hold the
second one, we consider the first as a dependency, and then consider the
second as a dependency when holding the third, causing a circular
dependency (since the third shares the same construction location as the
first).
This isn't considered a lockorder violation that could result in a
deadlock as the comment suggests inline though, since we are under a
dependent write lock which no one else can have access to.
If routing nodes take less fees and pay the final node more than
`amt_to_forward`, the receiver may see that `total_msat` has been met
before all of the sender's intended HTLCs have arrived. The receiver
may then prematurely claim the payment and release the payment hash,
allowing routing nodes to claim the remaining HTLCs. Using the onion
value `amt_to_forward` to determine when `total_msat` has been met
allows the sender to control the set total.
Final nodes previously had stricter requirements on HTLC contents
matching onion value compared to intermediate nodes. This allowed
for probing, i.e. the last intermediate node could overshoot the
value by a small amount and conclude from the acceptance or rejection
of the HTLC whether the next node was the destination. This also
applies to the msat amount, however this change was already present.
While retrying a failed path of an MPP, a node may want to overshoot
the `total_msat` in order to use a path with an `htlc_minimum_msat`
greater than the remaining value being sent. This commit no longer
fails MPPs that overshoot the `total_msat`, however it does fail
HTLCs with the same payment hash that are received *after* a
payment has become claimable.
This is pre-work for allowing nodes to overshoot onion values and
changing validation for MPP completion. This adds a field to
`ClaimableHTLC` that is separate from the onion values, which
represents the actual received amount reported in `PaymentClaimable`
which is what we want to validate against when a user goes to claim.
While users could easily figure it out based on the set of HTLC
descriptors included within, we already track it within the
`OnchainTxHandler`, so we might as well expose it to users as a
nice-to-have. It's also yet another thing they must get right to ensure
their HTLC transaction broadcasts are valid.
This only applies to all malleable packages on channels pre-dating
anchors and malleables packages for counterparty commitments
post-anchors. Malleables packages for holder commitments post-anchors
should have their transaction locktime applied manually by the consumer
of `BumpTransactionEvent::HTLCResolution` events.
Previously, this would return the earliest height the output could be
confirmed, which seems to no longer be useful. The only use of the
method was to determine whether we should delay a package to a future
block. Instead, we choose to return the absolute locktime the
transaction spending the output should have, which better corresponds to
the method name and still supports the delay functionality mentioned.
Doing so also allows us to expose the locktime required for HTLC
transactions we need to broadcast based on our own commitments for
anchor channels.
`OnceCell` doesn't call `drop`, which makes the spawned
`bitcoind`/`electrsd` instances linger around after our tests have
finished. To fix this, we move them out of `OnceCell` and let every test
that needs them spawn their own instances. This additional let us drop
the `OnceCell` dev dependency.
`ChannelMonitorUpdate`s are our most size-sensitive objects - they
are the minimal objects which need to be written to disk on each
commitment update. Thus, we should be careful to ensure we don't
pack too much extraneous information into each one.
Here we add future support for removing the per-HTLC explicit
`Option<Signature>` and `HTLCInCommitmentUpdate` for non-dust HTLCs
in holder commitment tx updates, which are redundant with the
`HolderCommitmentTransaction`.
While we cannot remove them entirely as previous versions rely on
them, adding support for filling in the in-memory structures from
the redundant fields will let us remove them in a future version.
We also add test-only generation logic to test the new derivation.
This is largely motivated by some follow-up work for anchors that will
introduce an event handler for `BumpTransaction` events, which we can
now include in this new top-level `events` module.
There is no need to fill the user's logs with errors that are expected
to be hit based on specific edge cases, like providing preimages after
a monitor has seen a confirmed commitment on-chain.
This doesn't really change our behavior – we still apply and persist the
state changes resulting from processing these updates regardless of
whether they succeed or not.
This results in a new, potentially redundant, `ChannelMonitorUpdate`
that must be applied to `ChannelMonitor`s to broadcast the holder's
latest commitment transaction.
This is a behavior change for anchor channels since their commitments
may require additional fees to be attached through a child anchor
transaction. Recall that anchor transactions are only generated by the
event consumer after processing a `BumpTransactionEvent::ChannelClose`
event, which is yielded after applying a
`ChannelMonitorUpdateStep::ChannelForceClosed` monitor update. Assuming
the node operator is not watching the mempool to generate these anchor
transactions without LDK, an anchor channel which we had to fail when
deserializing our `ChannelManager` would have its commitment transaction
broadcast by itself, potentially exposing the node operator to loss of
funds if the commitment transaction's fee is not enough to be accepted
into the network's mempools.
Currently, all that is required to force close a channel is to broadcast
either of the available commitment transactions, but this changes with
anchor outputs – commitment transactions may need to have
additional fees attached in order to confirm in a timely manner. While
we may be able to just queue a new update using the channel's next
available update ID, this may result in a violation of the
`ChannelMonitor` API (each update ID must strictly increase by 1) if the
channel had updates that were persisted by its `ChannelMonitor`, but not
the `ChannelManager`. Therefore, we choose to re-purpose the existing
`CLOSED_CHANNEL_UPDATE_ID` update ID to also apply to
`ChannelMonitorUpdate`s that will force close their respective channel
by broadcasting the holder's latest commitment transaction.
...replacing it with an acessor `addresses()`.
Besides removing a redundant data structure already present on inner
`NodeAnnouncement`, this change makes it possible to discover new address types
upon deserialization thanks to `UnsignedNodeAnnouncement`'s implementation.
`vec_type` is confusing - it is happy to have a missing entry,
"reading" an empty `Vec` instead, but always writes something,
making a serialization round-trip different.
This is a problem for writing a new `Vec` which is
backwards-incompatible, but only if filled in. In that case we'd
really like the same read behavior, but not write anything if the
`Vec` is empty. Here we introduce such semantics via a new
`optional_vec` TLV format.
