The instructions for `ChannelManagerReadArgs` indicate that you need
to connect blocks on a newly-deserialized `ChannelManager` in a
separate pass from the newly-deserialized `ChannelMontiors` as the
`ChannelManager` assumes the ability to update the monitors during
block [dis]connected events, saying that users need to:
```
4) Reconnect blocks on your ChannelMonitors
5) Move the ChannelMonitors into your local chain::Watch.
6) Disconnect/connect blocks on the ChannelManager.
```
This is fine for `ChannelManager`'s purpose, but is very awkward
for users. Notably, our new `lightning-block-sync` implemented
on-load reconnection in the most obvious (and performant) way -
connecting the blocks all at once, violating the
`ChannelManagerReadArgs` API.
Luckily, the events in question really don't need to be processed
with the same urgency as most channel monitor updates. The only two
monitor updates which can occur in block_[dis]connected is either
a) in block_connected, we identify a now-confirmed commitment
transaction, closing one of our channels, or
b) in block_disconnected, the funding transaction is reorganized
out of the chain, making our channel no longer funded.
In the case of (a), sending a monitor update which broadcasts a
conflicting holder commitment transaction is far from
time-critical, though we should still ensure we do it. In the case
of (b), we should try to broadcast our holder commitment transaction
when we can, but within a few minutes is fine on the scale of
block mining anyway.
Note that in both cases cannot simply move the logic to
ChannelMonitor::block[dis]_connected, as this could result in us
broadcasting a commitment transaction from ChannelMonitor, then
revoking the now-broadcasted state, and only then receiving the
block_[dis]connected event in the ChannelManager.
Thus, we move both events into an internal invent queue and process
them in timer_chan_freshness_every_min().
functional_tests.rs is huge, so anything we can do to split it up
some is helpful. This also exposes a somewhat glaring lack of
reorgs in our existing tests.
Given the chain::Watch interface is defined in terms of ChannelMonitor
and ChannelMonitorUpdateErr, move channelmonitor.rs from the ln module
to the chain module.
Rename ManyChannelMonitor to chain::Watch and move to chain/mod.rs,
where chain-related interfaces live. Update the documentation for
clarity and to conform to rustdoc formatting.
Replace direct uses of BlockNotifier in functional tests with utility
functions. This is in preparation for signaling watch events back via a
refactoring of ManyChannelMonitor and ChainWatchInterface. Those events
will be processed by connect_block.
ChainListeners should be independent of each other, but in practice this
is not the case because ChainWatchInterface introduces a dependency
between them. Push ChainWatchInterface down into the ChainListener
implementations where needed. Update ChainListener's block_connected
method to take a slice of the form &[(usize, &Transaction)] where each
transaction is paired with its position within the block.
To do this, we replace get_and_clear_pending_htlcs_updated with
get_and_clear_pending_monitor_events, and which still transmits HTLCUpdates
as before, but now also transmits a new MonitorEvent::CommitmentTxBroadcasted
event when a channel's commitment transaction is broadcasted.
This changes the LICENSE file and adds license headers to most files
to relicense under dual Apache-2.0 and MIT. This is helpful in that
we retain the patent grant issued under Apache-2.0-licensed work,
avoiding some sticky patent issues, while still allowing users who
are more comfortable with the simpler MIT license to use that.
See https://github.com/rust-bitcoin/rust-lightning/issues/659 for
relicensing statements from code authors.
Features for a given context are duplicated throughout the features
module. Use a macro for defining a Context and the applicable features
such that features only need to be defined for a Context in one place.
The Context provides bitmasks for selecting known and unknown feature
flags.
BOLT 1 and BOLT 9 refer to features as "known" if a peer understands
them. They also use the term "supported" to mean either optional or
required.
Update the features module to use similar terminology.
- Define contexts in terms of required and optional features rather than
just supported features
- Define known features as those that are optional or required
- Rename supported() constructor to known()
For completeness, clear_optional_bit for each feature is now called
clear_bits and clears both optional and required bits.
Base AMP is centered around the concept of a 'payment_secret` - an
opaque 32-byte random string which is used to authenticate the
sender to the recipient as well as tie the various HTLCs which
make up one payment together. This new field gets exposed in a
number of places, though sadly only as an Option for backwards
compatibility when sending to a receiver/receiving from a sender
which does not support Base AMP.
Sadly a huge diff here, but almost all of it is changing the method
signatures for sending/receiving/failing HTLCs and the
PaymentReceived event, which all now need to expose an
Option<[u8; 32]> for the payment_secret.
It doesn't yet properly fail back pending HTLCs when the full AMP
payment is never received (which should result in accidental
channel force-closures). Further, as sending AMP payments is not
yet supported, the only test here is a simple single-path payment
with a payment_secret in it.
The API to rust-bitcoin to check a transaction correctly spends
another changed some time ago, but we still have a lot of needless
.clone()s in our tests.
