We could have possibly constructed a slightly inconsistent
path: since we reduce value being transferred all the way, we
could have violated htlc_minimum_msat on some channels
we already passed (assuming dest->source direction). Here,
we recompute the fees again, so that if that's the case, we
match the currently underpaid htlc_minimum_msat with fees.
If the ChannelManager never receives any blocks, it'll return a default blockhash
on deserialization. It's preferable for this to be an Option instead.
Refactor synchronize_listeners by pulling out a function returning the
validated block header of a BlockSource's best chain tip. This is needed
when a node is started from scratch and has no listeners to sync.
The implementation of chain::Listen for ChannelMonitor required using a
RefCell since its block_connected method required a mutable borrow. This
is no longer the case since ChannelMonitor now uses interior mutability
via a Mutex. So the RefCell is no longer needed.
Now that ChannelMonitor uses an internal Mutex to support interior
mutability, ChainMonitor can use a RwLock to manage its ChannelMonitor
map. This allows parallelization of update_channel operations since an
exclusive lock only needs to be held when adding to the map in
watch_channel.
ChainMonitor accesses a set of ChannelMonitors behind a single Mutex.
As a result, update_channel operations cannot be parallelized. It also
requires using a RefCell around a ChannelMonitor when implementing
chain::Listen.
Moving the Mutex into ChannelMonitor avoids these problems and aligns it
better with other interfaces. Note, however, that get_funding_txo and
get_outputs_to_watch now clone the underlying data rather than returning
references.
We currently "support" not having a router or channel in memory by
forcing users to implement the same, but its trivial to provide our
own dummy implementations.
This will switch to use the clang/C WASM ABI instead of the
wasm_bindgen WASM ABI as of rustc 1.51 (or nightly since [1]),
allowing us to link C and Rust code in a single wasm binary.
[1] https://github.com/rust-lang/rust/pull/79998
For ChannelManager, at least, we have two separate functions called
block_connected, one in the Listen trait, one in the struct, we
need to be explicit with which one we're trying to call.
Add a utility for syncing a set of chain listeners to a common chain
tip. Required to use before creating an SpvClient when the chain
listener used with the client is actually a set of listeners each of
which may have had left off at a different block. This would occur when
the listeners had been persisted individually at different frequencies
(e.g., a ChainMonitor's individual ChannelMonitors).
Adds a lightweight client for polling one or more block sources for the
best chain tip. Notifies listeners of blocks connected or disconnected
since the last poll. Useful for keeping a Lightning node in sync with
the chain.
Add an interface for being notified of block connected and disconnected
events, along with a notifier for generating such events. Used while
polling block sources for a new tip in order to feed these events into
ChannelManager and ChainMonitor.
ChainPoller defines a strategy for polling a single BlockSource. It
handles validating chain data returned from the BlockSource. Thus, other
implementations of Poll must be defined in terms of ChainPoller.
SPV clients need to poll one or more block sources for the best chain
tip and to retrieve related chain data. The Poll trait serves as an
adaptor interface for BlockSource. Implementations may define an
appropriate polling strategy.
* Implemented protocol.
* Made feature optional.
* Verify that the default value is true.
* Verify that on shutdown,
if Channel.supports_shutdown_anysegwit is enabled,
the script can be a witness program.
* Added a test that verifies that a scriptpubkey
for an unreleased segwit version is handled successfully.
* Added a test that verifies that
if node has op_shutdown_anysegwit disabled,
a scriptpubkey with an unreleased segwit version on shutdown
throws an error.
* Added peer InitFeatures to handle_shutdown
* Check if shutdown script is valid when given upfront.
* Added a test to verify that an invalid test results in error.
* Added a test to check that if a segwit script with version 0 is provided,
the updated anysegwit check detects it and returns unsupported.
* An empty script is only allowed when sent as upfront shutdown script,
so make sure that check is only done for accept/open_channel situations.
* Instead of reimplementing a variant of is_witness_script,
just call it and verify that the witness version is not 0.
