Given the chain::Watch interface is defined in terms of ChannelMonitor
and ChannelMonitorUpdateErr, move channelmonitor.rs from the ln module
to the chain module.
Outputs to watch are tracked by ChannelMonitor as of
73dce207dd. Instead of determining new
outputs to watch independently using ChainWatchedUtil, do so by
comparing against outputs already tracked. Thus, ChainWatchedUtil and
WatchEvent are no longer needed.
WatchEventProvider served as a means for replacing ChainWatchInterface.
However, it requires users to explicitly fetch WatchEvents, even if not
interested in them. Replace WatchEventProvider by chain::Filter, which
is an optional member of ChainMonitor. If set, interesting transactions
and output spends are registered such that blocks containing them can be
retrieved from a chain source in an efficient manner.
This is useful when the chain source is not a full node. For Electrum,
it allows for pre-filtered blocks. For BIP157/158, it serves as a means
to match against compact filters.
ChainMonitor's template Key parameter was meant to allow supporting
both local monitoring, where Key=OutPoint, and watchtowers, where Key=
(PublicKey, u32). Use OutPoint directly since the watchtower case will
not be supported this way.
ManyChannelMonitor was renamed chain::Watch in the previous commit. Use
a more concise name for an implementation that monitors the chain for
channel activity. Future work will parameterize the struct to allow for
different varieties of persistence. Thus, users usually will be able to
use ChainMonitor directly rather than implementing a chain::Watch that
wraps it.
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.
ChainWatchInterface was intended as an interface for watching rather
than accessing the chain. Remove get_chain_utxo and add chain::Access
trait for this behavior. Wrap it with an Option in NetGraphMsgHandler in
order to simplify the error interface.
Use of ChainWatchInterface was replaced with WatchEvent in the previous
commit. Remove it from the parameterization of SimpleManyChannelMonitor
since it is no longer needed.
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.
We'd previously largely not turned on derive(Debug) on any of our
structs, but not for good reason. Especially for Events objects,
Debug can be a very useful for users to quickly print what they
received from us without having to write out a large match.
Comment meaning of holder/counterparty
Diverse chan_utils cleanups
Cleanups post-cbindings merge
Fix misusage of holder_selected_contest_delay instead of counterparty
_selected_contest_delay in HolderCommitmentTransaction
Fix old payment_point comment
A TxCreationKeys set represents the key which will be embedded in output
scripts of a party's commitment tx state. Among them there is a always
a key belonging to counter-party, the HTLC pubkey. To dissociate
strongly, prefix keys with broadcaster/countersignatory.
A revocation keypair is attributed to the broadcaster as it's used
to punish a fraudulent broadcast while minding that such keypair
derivation method will be always used by countersignatory as it's
its task to enforce punishement thanks to the release secret.
To avoid reviewers confusion, rename counterparty_to_self_delay
to counteparty_selected_contest_delay, i.e the justice delay announced
by a channel counterparty restraining our transactions, and to_self_delay
to locally_selected_contest_delay, i.e the justice delay announced by us
restraining counterparty's transactions
We deviate from wider nomenclature by prefixing local data with a
locally_ extension due to the leak of this value in transactions/scripts
builder, where the confusion may happen.
Rename further AcceptChannelData to the new nomenclature.
Variables should be named according to the script semantic which is
an invariant with regards to generating a local or remote commitment
transaction.
I.e a broadcaster_htlc_key will always guard a HTLC to the party able
to broadcast the computed transactions whereas countersignatory_htlc_key
will guard HTLC to a countersignatory of the commitment transaction.
The C bindings automatically create a _new() function for structs
which contain only pub fields which we know how to map. This
conflicts with the actual TxCreationKeys::new() function, so we
simply rename it to capture its nature as a derivation function.
Lightning OutPoints only have 16 bits to express the output index
instead of Bitcoin's 32 bits, implying that some outputs are
possibly not expressible as lightning OutPoints. However, such
OutPoints can never be hit within the lightning protocol, and must
be on-chain spam sent by a third party wishing to donate us money.
Still, in order to do so, the third party would need to fill nearly
an entire block with garbage, so this case should be relatively
safe.
A new comment in channelmonitor explains the reasoning a bit
further.
There are a few cases where the upcoming C bindings don't know how
to handle something which depends on something defined later in the
file. Instead of adding another pass to the C bindings generator,
it is much simpler to just reorder structs.
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.
Due to a desire to be able to override temporary channel IDs and
onion keys, KeysInterface had two separate fetch-random-32-bytes
interfaces - an onion-key specific version which fetched 2 random
32 byte strings and a temporary-channel-id specific version.
It turns out, we never actually need to override both at once (as
creating a new channel and sending an outbound payment are always
separate top-level calls), so there's no reason to add two
functions to the interface when both really do the same thing.
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.
Allows calling of InMemoryChannelKeys methods.
The wrapping makes it obvious to signer implementers that the pre-derived keys are a local cache and should not be trusted in a validating signer.
The commitment secret is sensitive - it can be used by an attacker to
steal funds if the node also signs the same transaction. Therefore,
only release the secret from ChannelKeys when we are revoking a
transaction.
... for ChannelError and APIMisuseError
Before this commit, When rl returns error, we don't know
The actual parameter which caused the error.
By returning parameterised `String` instead of predefined `&'static str`,
We can give a caller improved error message.
TestLogger now has two additional methods
1. `assert_log_contains` which checks the logged messsage
has how many entry which includes the specified string as a substring.
2. `aasert_log_regex` mostly the same with `assert_log_contains`
but it is more flexible that caller specifies regex which has
to be satisfied instead of just a substring.
For regex, tests now includes `regex` as dev-dependency.
We use them largely as indexes into a Vec<Transaction> so there's
little reason for them to be u32s. Instead, use them as usize
everywhere.
We also take this opportunity to add range checks before
short_channel_id calculation, as we could otherwise end up with a
bogus short_channel_id due to an output index out of range.
Instead of making the filter_block fn in the ChainWatchInterface
trait return both a list of indexes of transaction positions within
the block and references to the transactions themselves, return
only the list of indexes and then build the reference list at the
callsite.
While this may be slightly less effecient from a memory locality
perspective, it shouldn't be materially different.
This should make it more practical to generate bindings for
filter_block as it no longer needs to reference Rust Transaction
objects that are contained in a Rust Block object (which we'd
otherwise just pass over the FFI in fully-serialized form).
In general, we don't need an explicit lifetime when doing something
like:
fn get_thing(&self) -> &Thing { &self.thing }.
This also makes it easier to reason about what's going on in the
bindings generation.
Tests use sources of randomness to produce seeds, preimages, secrets,
and ephemeral data. However, this makes comparing logs between different
test runs difficult. Remove uses of random number generators and the
current time in favor of fixed values in order to make the test output
deterministic.
