This adds a new method to the general cross-channel `KeysInterface`
which requires it to handle the deserialization of per-channel
signer objects. This allows the deserialization of per-channel
signers to have more context available, which, in the case of the
C bindings, includes the actual KeysInterface information itself.
There's no reason to have ChannelMonitor::write_for_disk instead of
just using the Writeable trait anymore. Previously, it was used to
differentiate with `write_for_watchtower`, but support for
watchtower-mode ChannelMonitors was never completed and the partial
bits were removed long ago.
This has the nice benefit of hitting the custom Writeable codepaths
in C bindings instead of trying to hit trait-generics paths.
It doesn't make sense to ever build a lightning node which doesn't
ever write ChannelMonitors to disk, so having a ChannelKeys object
which doesn't implement Writeable is nonsense.
Here we require Writeable for all ChannelKeys objects, simplifying
code generation for C bindings somewhat.
We only actually use two of the fields in ChannelKeys inside a
ChannelMonitor - the holder revocation_basepoint and the
derivation parameters. Both are relatively small, so there isn't
a lot of reason to hold a full copy of the ChannelKeys (with most
of the interaction with it being inside the OnchainTxHandler).
Further, this will avoid calling read on a `ChannelKeys` twice,
which is a somewhat strange API quirk.
CommitmentTransaction maintains the per-commitment transaction fields needed to construct the associated bitcoin transactions (commitment, HTLC). It replaces passing around of Bitcoin transactions. The ChannelKeys API is modified accordingly.
By regenerating the transaction when implementing a validating external signer, this allows a higher level of assurance that all relevant aspects of the transactions were checked for policy violations.
ChannelTransactionParameters replaces passing around of individual per-channel fields that are needed to construct Bitcoin transactions.
Eliminate ChannelStaticData in favor of ChannelTransactionParameters.
Use counterparty txid instead of tx in channelmonitor update.
This method was used to set the initial_routing_sync flag when sending
an outbound Init message to a peer. Since we are now relying on
gossip_queries instead of initial_routing_sync, synchronization can be
fully encapsulate into RoutingMessageHandler via sync_routing_table.
This commit removes should_request_full_sync from the trait
RoutingMessageHandler. The implementation is still used in
NetGraphMsgHandler and has been converted into a private method instead
of a trait function.
This commit changes outbound routing table sync to use gossip_queries
instead of the effectively deprecated initial_routing_sync feature.
This change removes setting of initial_routing_sync in our outbound Init
message. Instead we now call sync_routing_table after receiving an Init
message from a peer. If the peer supports gossip_queries and
should_request_full_sync returns true, we initiate a full gossip_queries
sync.
This commit modifies sync_routing_table in RoutingMessageHandler to
accept a reference to the Init message received by the peer. This allows
the method to use the Peer's features to drive the operations of the
gossip_queries routing table sync.
This change modifies gossip_queries methods in RoutingMessageHandler to
move the message instead of passing a reference. This allows the message
handler to be more efficient by not requiring a full copy of SCIDs
passed in messages.
This commit simplifies the sync process for routing gossip messages. When
a sync is initiated, the process is handled statelessly by immediately
issuing SCID queries as channel range replies are received. This greatly
simplifies the state machine at the cost of fully validating and
conforming to the current spec.
This changes adds the genesis block hash as a BlockHash to the
NetworkGraph struct. Making the NetworkGraph aware allows the message
handler to validate the chain_hash for received messages. This change
also adds the hash value to the Writeable and Readable methods.
To perform a sync of routing gossip messages with a peer requires a two
step process where we first initiate a channel range query to discover
channels in a block range. Next we request the routing gossip messages
for discovered channels.
This code implements logic in NetGraphMsgHandler for performing these two
tasks while taking into account the specification and variance in
implementation.
Defines message handlers for gossip_queries messages in the RoutingMessageHandler
trait. The MessageSendEventsProvider supertrait is added to RoutingMessageHandler
so that the implementor can use SendMessageEvents to send messages to a
peer at the appropriate time.
The trait methods are stubbed in NetGraphMsgHandler which implements
RoutingMessageHandler and return a "not implemented" error.
This change enables initiating gossip queries with a peer using the
SendMessageEvent enum. Specifically we add an event for sending
query_channel_range to discover the existance of channels and an event
for sending query_short_channel_ids to request routing gossip messages
for a set of channels. These events are handled inside the process_events
method of PeerManager which sends the serialized message to the peer.
To enable gossip_queries message decoding, this commit implements the
wire module's Encoding trait for each message type. It also adds these
messages to the wire module's Message enum and the read function to
enable decoding of a buffer.
Support for the gossip_queries feature flag (bits 6/7) is added to the
Features struct. This feature is available in the Init and Node
contexts. The gossip_queries feature is not fully implemented so this
feature is disabled when sent to peers in the Init message.
This takes the now-public `NetworkGraph` message handling functions
and splits them all into two methods - one which takes a required
Secp256k1 context and verifies signatures and one which takes only
the unsigned part of the message and does not take a Secp256k1
context.
This both clarifies the public API as well as simplifies it, all
without duplicating code.
Finally, this adds an assertion in the Router fuzzer to make sure
the constants used for message deserialization are correct.
This makes the public utility methods in `NetworkGraph` able to do
UTXO lookups ala `NetworkMsgHandler`'s `RoutingMessageHandler`
implementation, slightly simplifying the public interface.
We also take this opportunity to verify signatures before calling
out to UTXO lookups, under the "do actions in order of
cheapest-to-most-expensive to reduce DoS surface" principle.
These functions were created but previously not exported, however
they are useful if we want to skip signature checking when accepting
routing messages (which we really should be doing in the routing
fuzzer).
Like the previous commit for channel-closed monitor updates for
inbound channels during processing of a funding_created message,
this resolves a more general issue for closing outbound channels
which have sent a funding_created but not yet received a
funding_signed.
This issue was also detected by full_stack_target.
To make similar issues easier to detect in testing and fuzzing, an
additional assertion is added to panic on updates to a channel
monitor before registering it.
The full_stack_target managed to find a bug where, if we receive
a funding_created message which has a channel_id identical to an
existing channel, we'll end up
(a) having the monitor update for the new channel fail (due to
duplicate outpoint),
(b) creating a monitor update for the new channel as we
force-close it,
(c) panicing due to the force-close monitor update is applied to
the original channel and is considered out-of-order.
Obviously we shouldn't be creating a force-close monitor update for
a channel which can never appear on chain, so we do that here and
add a test which previously failed and checks a few
duplicate-channel-id cases.
In updating the router fuzzer, it discovered that a remote peer can
cause us to overflow while multiplying the channel capacity value.
Since the value should never exceed 21 million BTC, we just add a
check for that.
We had code in the router to support sending a payment via a single
hop across channels exclusively provided by the next-/last-hop hints.
However, in updating the fuzzer, I noted that this case not only
didn't work, but paniced in some cases.
Here, we both fix the panic, as well as write a new test which
ensures we don't break support for such routing in the future.
If we receive a preimage for an outgoing HTLC that solves an output on a
backwards force-closed channel, we need to claim the output on-chain.
Note that this commit also gets rid of the channel monitor redundantly setting
`self.counterparty_payment_script` in `check_spend_counterparty_transaction`.
Co-authored-by: Antoine Riard <ariard@student.42.fr>
Co-authored-by: Valentine Wallace <vwallace@protonmail.com>
Now callers will separately retrieve the claim requests/
holder revokable script and the new watched holder outputs.
This will be used in the next commit for times when we
need to get holder claim requests, but don't have access to
the holder commitment transaction.
Helpful for debugging. I also included the change in the provide_preimage method
signature which will be used in an upcoming commit, because commit-wise it was
easier to combine the changes.
If the channel is hitting the chain right as we receive a preimage,
previous to this commit the relevant ChannelMonitor would never
learn of this preimage.
The ChannelMonitor already monitors the chain for counterparties
revealing preimages, and will give the HTLCSources back to the
ChannelManager for claiming. Thus it's unnecessary for the ChannelManager
to monitor these HTLCs itself.
See is_resolving_htlc_output:
- if the counterparty broadcasted and then claimed one of the HTLCs we
offered them, line 2015 is where the ChannelMonitor gives the ChannelManager
the HTLC source
- if we broadcasted and they claimed an HTLC we offered them, line 2025 is
where the ChannelMonitor gives the ChannelManager the HTLC source
If a persister returns a temporary failure, the channel monitor should be able
to be put on ice and then revived later. If a persister returns a permanent
failure, the channel should be force closed.
Intended to be a cross-platform implementation of the
channelmonitor::Persist trait.
This adds a new lightning-persister crate, that uses the
newly exposed lightning crate's test utilities.
Notably, this crate is pretty small right now. However, due to
future plans to add more data persistence (e.g. persisting the
ChannelManager, etc) and a desire to avoid pulling in filesystem
usage into the core lightning package, it is best for it to be
separated out.
Note: Windows necessitates the use of OpenOptions with the `write`
permission enabled to `sync_all` on a newly opened channel's
data file.
- The ChainMonitor should:
Whenever a new channel is added or updated, these updates
should be conveyed to the persister and persisted to disk.
Even if the update errors while it's being applied, the
updated monitor still needs to be persisted.
We remove test_no_failure_dust_htlc_local_commitment from our test
framework as this test deliberately throwing junk transaction in
our monitoring parsing code is hitting new assertions.
This test was added in #333, but it sounds as an oversight as the
correctness intention of this test (i.e verifying lack of dust
HTLCs canceling back in case of junk commitment transaction) doesn't
currently break.
This test is a mutation to underscore the detetection logic bug
we had before #653. HTLC value routed is above the remaining
balance, thus inverting HTLC and `to_remote` output. HTLC
will come second and it wouldn't be seen by pre-#653 detection
as we were eneumerate()'ing on a watched outputs vector (Vec<TxOut>)
thus implictly relying on outputs order detection for correct
spending children filtering.
Previously, outputs were monitored based on txid and an index yelled
from an enumeration over the returned selected outputs by monitoring
code. This is always have been broken but was only discovered while
introducing anchor outputs as those ones rank always first per BIP69.
We didn't have test cases where a HTLC was bigger than a party balance
on a holder commitment and thus not ranking first.
Next commit introduce test coverage.
