1 // This file is Copyright its original authors, visible in version control
4 // This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
5 // or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
6 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
7 // You may not use this file except in accordance with one or both of these
10 //! Events are returned from various bits in the library which indicate some action must be taken
13 //! Because we don't have a built-in runtime, it's up to the client to call events at a time in the
14 //! future, as well as generate and broadcast funding transactions handle payment preimages and a
17 use chain::keysinterface::SpendableOutputDescriptor;
18 use ln::channelmanager::PaymentId;
19 use ln::channel::FUNDING_CONF_DEADLINE_BLOCKS;
20 use ln::features::ChannelTypeFeatures;
22 use ln::msgs::DecodeError;
23 use ln::{PaymentPreimage, PaymentHash, PaymentSecret};
24 use routing::gossip::NetworkUpdate;
25 use util::ser::{BigSize, FixedLengthReader, Writeable, Writer, MaybeReadable, Readable, VecReadWrapper, VecWriteWrapper};
26 use routing::router::{RouteHop, RouteParameters};
28 use bitcoin::Transaction;
29 use bitcoin::blockdata::script::Script;
30 use bitcoin::hashes::Hash;
31 use bitcoin::hashes::sha256::Hash as Sha256;
32 use bitcoin::secp256k1::PublicKey;
35 use core::time::Duration;
39 /// Some information provided on receipt of payment depends on whether the payment received is a
40 /// spontaneous payment or a "conventional" lightning payment that's paying an invoice.
41 #[derive(Clone, Debug)]
42 pub enum PaymentPurpose {
43 /// Information for receiving a payment that we generated an invoice for.
45 /// The preimage to the payment_hash, if the payment hash (and secret) were fetched via
46 /// [`ChannelManager::create_inbound_payment`]. If provided, this can be handed directly to
47 /// [`ChannelManager::claim_funds`].
49 /// [`ChannelManager::create_inbound_payment`]: crate::ln::channelmanager::ChannelManager::create_inbound_payment
50 /// [`ChannelManager::claim_funds`]: crate::ln::channelmanager::ChannelManager::claim_funds
51 payment_preimage: Option<PaymentPreimage>,
52 /// The "payment secret". This authenticates the sender to the recipient, preventing a
53 /// number of deanonymization attacks during the routing process.
54 /// It is provided here for your reference, however its accuracy is enforced directly by
55 /// [`ChannelManager`] using the values you previously provided to
56 /// [`ChannelManager::create_inbound_payment`] or
57 /// [`ChannelManager::create_inbound_payment_for_hash`].
59 /// [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
60 /// [`ChannelManager::create_inbound_payment`]: crate::ln::channelmanager::ChannelManager::create_inbound_payment
61 /// [`ChannelManager::create_inbound_payment_for_hash`]: crate::ln::channelmanager::ChannelManager::create_inbound_payment_for_hash
62 payment_secret: PaymentSecret,
64 /// Because this is a spontaneous payment, the payer generated their own preimage rather than us
65 /// (the payee) providing a preimage.
66 SpontaneousPayment(PaymentPreimage),
69 impl_writeable_tlv_based_enum!(PaymentPurpose,
70 (0, InvoicePayment) => {
71 (0, payment_preimage, option),
72 (2, payment_secret, required),
74 (2, SpontaneousPayment)
77 #[derive(Clone, Debug, PartialEq)]
78 /// The reason the channel was closed. See individual variants more details.
79 pub enum ClosureReason {
80 /// Closure generated from receiving a peer error message.
82 /// Our counterparty may have broadcasted their latest commitment state, and we have
84 CounterpartyForceClosed {
85 /// The error which the peer sent us.
87 /// The string should be sanitized before it is used (e.g emitted to logs
88 /// or printed to stdout). Otherwise, a well crafted error message may exploit
89 /// a security vulnerability in the terminal emulator or the logging subsystem.
92 /// Closure generated from [`ChannelManager::force_close_channel`], called by the user.
94 /// [`ChannelManager::force_close_channel`]: crate::ln::channelmanager::ChannelManager::force_close_channel.
96 /// The channel was closed after negotiating a cooperative close and we've now broadcasted
97 /// the cooperative close transaction. Note the shutdown may have been initiated by us.
98 //TODO: split between CounterpartyInitiated/LocallyInitiated
100 /// A commitment transaction was confirmed on chain, closing the channel. Most likely this
101 /// commitment transaction came from our counterparty, but it may also have come from
102 /// a copy of our own `ChannelMonitor`.
103 CommitmentTxConfirmed,
104 /// The funding transaction failed to confirm in a timely manner on an inbound channel.
106 /// Closure generated from processing an event, likely a HTLC forward/relay/reception.
108 /// A developer-readable error message which we generated.
111 /// The peer disconnected prior to funding completing. In this case the spec mandates that we
112 /// forget the channel entirely - we can attempt again if the peer reconnects.
114 /// In LDK versions prior to 0.0.107 this could also occur if we were unable to connect to the
115 /// peer because of mutual incompatibility between us and our channel counterparty.
117 /// Closure generated from `ChannelManager::read` if the ChannelMonitor is newer than
118 /// the ChannelManager deserialized.
119 OutdatedChannelManager
122 impl core::fmt::Display for ClosureReason {
123 fn fmt(&self, f: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {
124 f.write_str("Channel closed because ")?;
126 ClosureReason::CounterpartyForceClosed { peer_msg } => {
127 f.write_str("counterparty force-closed with message ")?;
128 f.write_str(&peer_msg)
130 ClosureReason::HolderForceClosed => f.write_str("user manually force-closed the channel"),
131 ClosureReason::CooperativeClosure => f.write_str("the channel was cooperatively closed"),
132 ClosureReason::CommitmentTxConfirmed => f.write_str("commitment or closing transaction was confirmed on chain."),
133 ClosureReason::FundingTimedOut => write!(f, "funding transaction failed to confirm within {} blocks", FUNDING_CONF_DEADLINE_BLOCKS),
134 ClosureReason::ProcessingError { err } => {
135 f.write_str("of an exception: ")?;
138 ClosureReason::DisconnectedPeer => f.write_str("the peer disconnected prior to the channel being funded"),
139 ClosureReason::OutdatedChannelManager => f.write_str("the ChannelManager read from disk was stale compared to ChannelMonitor(s)"),
144 impl_writeable_tlv_based_enum_upgradable!(ClosureReason,
145 (0, CounterpartyForceClosed) => { (1, peer_msg, required) },
146 (1, FundingTimedOut) => {},
147 (2, HolderForceClosed) => {},
148 (6, CommitmentTxConfirmed) => {},
149 (4, CooperativeClosure) => {},
150 (8, ProcessingError) => { (1, err, required) },
151 (10, DisconnectedPeer) => {},
152 (12, OutdatedChannelManager) => {},
155 /// Intended destination of a failed HTLC as indicated in [`Event::HTLCHandlingFailed`].
156 #[derive(Clone, Debug, PartialEq)]
157 pub enum HTLCDestination {
158 /// We tried forwarding to a channel but failed to do so. An example of such an instance is when
159 /// there is insufficient capacity in our outbound channel.
161 /// The `node_id` of the next node. For backwards compatibility, this field is
162 /// marked as optional, versions prior to 0.0.110 may not always be able to provide
163 /// counterparty node information.
164 node_id: Option<PublicKey>,
165 /// The outgoing `channel_id` between us and the next node.
166 channel_id: [u8; 32],
168 /// Scenario where we are unsure of the next node to forward the HTLC to.
170 /// Short channel id we are requesting to forward an HTLC to.
171 requested_forward_scid: u64,
173 /// Failure scenario where an HTLC may have been forwarded to be intended for us,
174 /// but is invalid for some reason, so we reject it.
176 /// Some of the reasons may include:
178 /// * Expected MPP amount to claim does not equal HTLC total
179 /// * Claimable amount does not match expected amount
181 /// The payment hash of the payment we attempted to process.
182 payment_hash: PaymentHash
186 impl_writeable_tlv_based_enum_upgradable!(HTLCDestination,
187 (0, NextHopChannel) => {
188 (0, node_id, required),
189 (2, channel_id, required),
191 (2, UnknownNextHop) => {
192 (0, requested_forward_scid, required),
194 (4, FailedPayment) => {
195 (0, payment_hash, required),
199 /// An Event which you should probably take some action in response to.
201 /// Note that while Writeable and Readable are implemented for Event, you probably shouldn't use
202 /// them directly as they don't round-trip exactly (for example FundingGenerationReady is never
203 /// written as it makes no sense to respond to it after reconnecting to peers).
204 #[derive(Clone, Debug)]
206 /// Used to indicate that the client should generate a funding transaction with the given
207 /// parameters and then call [`ChannelManager::funding_transaction_generated`].
208 /// Generated in [`ChannelManager`] message handling.
209 /// Note that *all inputs* in the funding transaction must spend SegWit outputs or your
210 /// counterparty can steal your funds!
212 /// [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
213 /// [`ChannelManager::funding_transaction_generated`]: crate::ln::channelmanager::ChannelManager::funding_transaction_generated
214 FundingGenerationReady {
215 /// The random channel_id we picked which you'll need to pass into
216 /// [`ChannelManager::funding_transaction_generated`].
218 /// [`ChannelManager::funding_transaction_generated`]: crate::ln::channelmanager::ChannelManager::funding_transaction_generated
219 temporary_channel_id: [u8; 32],
220 /// The counterparty's node_id, which you'll need to pass back into
221 /// [`ChannelManager::funding_transaction_generated`].
223 /// [`ChannelManager::funding_transaction_generated`]: crate::ln::channelmanager::ChannelManager::funding_transaction_generated
224 counterparty_node_id: PublicKey,
225 /// The value, in satoshis, that the output should have.
226 channel_value_satoshis: u64,
227 /// The script which should be used in the transaction output.
228 output_script: Script,
229 /// The `user_channel_id` value passed in to [`ChannelManager::create_channel`], or 0 for
230 /// an inbound channel.
232 /// [`ChannelManager::create_channel`]: crate::ln::channelmanager::ChannelManager::create_channel
233 user_channel_id: u64,
235 /// Indicates we've received (an offer of) money! Just gotta dig out that payment preimage and
236 /// feed it to [`ChannelManager::claim_funds`] to get it....
238 /// Note that if the preimage is not known, you should call
239 /// [`ChannelManager::fail_htlc_backwards`] to free up resources for this HTLC and avoid
240 /// network congestion.
241 /// If you fail to call either [`ChannelManager::claim_funds`] or
242 /// [`ChannelManager::fail_htlc_backwards`] within the HTLC's timeout, the HTLC will be
243 /// automatically failed.
246 /// LDK will not stop an inbound payment from being paid multiple times, so multiple
247 /// `PaymentReceived` events may be generated for the same payment.
249 /// [`ChannelManager::claim_funds`]: crate::ln::channelmanager::ChannelManager::claim_funds
250 /// [`ChannelManager::fail_htlc_backwards`]: crate::ln::channelmanager::ChannelManager::fail_htlc_backwards
252 /// The hash for which the preimage should be handed to the ChannelManager. Note that LDK will
253 /// not stop you from registering duplicate payment hashes for inbound payments.
254 payment_hash: PaymentHash,
255 /// The value, in thousandths of a satoshi, that this payment is for.
257 /// Information for claiming this received payment, based on whether the purpose of the
258 /// payment is to pay an invoice or to send a spontaneous payment.
259 purpose: PaymentPurpose,
261 /// Indicates a payment has been claimed and we've received money!
263 /// This most likely occurs when [`ChannelManager::claim_funds`] has been called in response
264 /// to an [`Event::PaymentReceived`]. However, if we previously crashed during a
265 /// [`ChannelManager::claim_funds`] call you may see this event without a corresponding
266 /// [`Event::PaymentReceived`] event.
269 /// LDK will not stop an inbound payment from being paid multiple times, so multiple
270 /// `PaymentReceived` events may be generated for the same payment. If you then call
271 /// [`ChannelManager::claim_funds`] twice for the same [`Event::PaymentReceived`] you may get
272 /// multiple `PaymentClaimed` events.
274 /// [`ChannelManager::claim_funds`]: crate::ln::channelmanager::ChannelManager::claim_funds
276 /// The payment hash of the claimed payment. Note that LDK will not stop you from
277 /// registering duplicate payment hashes for inbound payments.
278 payment_hash: PaymentHash,
279 /// The value, in thousandths of a satoshi, that this payment is for.
281 /// The purpose of this claimed payment, i.e. whether the payment was for an invoice or a
282 /// spontaneous payment.
283 purpose: PaymentPurpose,
285 /// Indicates an outbound payment we made succeeded (i.e. it made it all the way to its target
286 /// and we got back the payment preimage for it).
288 /// Note for MPP payments: in rare cases, this event may be preceded by a `PaymentPathFailed`
289 /// event. In this situation, you SHOULD treat this payment as having succeeded.
291 /// The id returned by [`ChannelManager::send_payment`] and used with
292 /// [`ChannelManager::retry_payment`].
294 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
295 /// [`ChannelManager::retry_payment`]: crate::ln::channelmanager::ChannelManager::retry_payment
296 payment_id: Option<PaymentId>,
297 /// The preimage to the hash given to ChannelManager::send_payment.
298 /// Note that this serves as a payment receipt, if you wish to have such a thing, you must
299 /// store it somehow!
300 payment_preimage: PaymentPreimage,
301 /// The hash that was given to [`ChannelManager::send_payment`].
303 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
304 payment_hash: PaymentHash,
305 /// The total fee which was spent at intermediate hops in this payment, across all paths.
307 /// Note that, like [`Route::get_total_fees`] this does *not* include any potential
308 /// overpayment to the recipient node.
310 /// If the recipient or an intermediate node misbehaves and gives us free money, this may
311 /// overstate the amount paid, though this is unlikely.
313 /// [`Route::get_total_fees`]: crate::routing::router::Route::get_total_fees
314 fee_paid_msat: Option<u64>,
316 /// Indicates an outbound payment failed. Individual [`Event::PaymentPathFailed`] events
317 /// provide failure information for each MPP part in the payment.
319 /// This event is provided once there are no further pending HTLCs for the payment and the
320 /// payment is no longer retryable, either due to a several-block timeout or because
321 /// [`ChannelManager::abandon_payment`] was previously called for the corresponding payment.
323 /// [`ChannelManager::abandon_payment`]: crate::ln::channelmanager::ChannelManager::abandon_payment
325 /// The id returned by [`ChannelManager::send_payment`] and used with
326 /// [`ChannelManager::retry_payment`] and [`ChannelManager::abandon_payment`].
328 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
329 /// [`ChannelManager::retry_payment`]: crate::ln::channelmanager::ChannelManager::retry_payment
330 /// [`ChannelManager::abandon_payment`]: crate::ln::channelmanager::ChannelManager::abandon_payment
331 payment_id: PaymentId,
332 /// The hash that was given to [`ChannelManager::send_payment`].
334 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
335 payment_hash: PaymentHash,
337 /// Indicates that a path for an outbound payment was successful.
339 /// Always generated after [`Event::PaymentSent`] and thus useful for scoring channels. See
340 /// [`Event::PaymentSent`] for obtaining the payment preimage.
341 PaymentPathSuccessful {
342 /// The id returned by [`ChannelManager::send_payment`] and used with
343 /// [`ChannelManager::retry_payment`].
345 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
346 /// [`ChannelManager::retry_payment`]: crate::ln::channelmanager::ChannelManager::retry_payment
347 payment_id: PaymentId,
348 /// The hash that was given to [`ChannelManager::send_payment`].
350 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
351 payment_hash: Option<PaymentHash>,
352 /// The payment path that was successful.
354 /// May contain a closed channel if the HTLC sent along the path was fulfilled on chain.
357 /// Indicates an outbound HTLC we sent failed. Probably some intermediary node dropped
358 /// something. You may wish to retry with a different route.
360 /// Note that this does *not* indicate that all paths for an MPP payment have failed, see
361 /// [`Event::PaymentFailed`] and [`all_paths_failed`].
363 /// [`all_paths_failed`]: Self::PaymentPathFailed::all_paths_failed
365 /// The id returned by [`ChannelManager::send_payment`] and used with
366 /// [`ChannelManager::retry_payment`] and [`ChannelManager::abandon_payment`].
368 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
369 /// [`ChannelManager::retry_payment`]: crate::ln::channelmanager::ChannelManager::retry_payment
370 /// [`ChannelManager::abandon_payment`]: crate::ln::channelmanager::ChannelManager::abandon_payment
371 payment_id: Option<PaymentId>,
372 /// The hash that was given to [`ChannelManager::send_payment`].
374 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
375 payment_hash: PaymentHash,
376 /// Indicates the payment was rejected for some reason by the recipient. This implies that
377 /// the payment has failed, not just the route in question. If this is not set, you may
378 /// retry the payment via a different route.
379 rejected_by_dest: bool,
380 /// Any failure information conveyed via the Onion return packet by a node along the failed
383 /// Should be applied to the [`NetworkGraph`] so that routing decisions can take into
384 /// account the update.
386 /// [`NetworkGraph`]: crate::routing::gossip::NetworkGraph
387 network_update: Option<NetworkUpdate>,
388 /// For both single-path and multi-path payments, this is set if all paths of the payment have
389 /// failed. This will be set to false if (1) this is an MPP payment and (2) other parts of the
390 /// larger MPP payment were still in flight when this event was generated.
392 /// Note that if you are retrying individual MPP parts, using this value to determine if a
393 /// payment has fully failed is race-y. Because multiple failures can happen prior to events
394 /// being processed, you may retry in response to a first failure, with a second failure
395 /// (with `all_paths_failed` set) still pending. Then, when the second failure is processed
396 /// you will see `all_paths_failed` set even though the retry of the first failure still
397 /// has an associated in-flight HTLC. See (1) for an example of such a failure.
399 /// If you wish to retry individual MPP parts and learn when a payment has failed, you must
400 /// call [`ChannelManager::abandon_payment`] and wait for a [`Event::PaymentFailed`] event.
402 /// (1) <https://github.com/lightningdevkit/rust-lightning/issues/1164>
404 /// [`ChannelManager::abandon_payment`]: crate::ln::channelmanager::ChannelManager::abandon_payment
405 all_paths_failed: bool,
406 /// The payment path that failed.
408 /// The channel responsible for the failed payment path.
410 /// Note that for route hints or for the first hop in a path this may be an SCID alias and
411 /// may not refer to a channel in the public network graph. These aliases may also collide
412 /// with channels in the public network graph.
414 /// If this is `Some`, then the corresponding channel should be avoided when the payment is
415 /// retried. May be `None` for older [`Event`] serializations.
416 short_channel_id: Option<u64>,
417 /// Parameters needed to compute a new [`Route`] when retrying the failed payment path.
419 /// See [`find_route`] for details.
421 /// [`Route`]: crate::routing::router::Route
422 /// [`find_route`]: crate::routing::router::find_route
423 retry: Option<RouteParameters>,
425 error_code: Option<u16>,
427 error_data: Option<Vec<u8>>,
429 /// Indicates that a probe payment we sent returned successful, i.e., only failed at the destination.
431 /// The id returned by [`ChannelManager::send_probe`].
433 /// [`ChannelManager::send_probe`]: crate::ln::channelmanager::ChannelManager::send_probe
434 payment_id: PaymentId,
435 /// The hash generated by [`ChannelManager::send_probe`].
437 /// [`ChannelManager::send_probe`]: crate::ln::channelmanager::ChannelManager::send_probe
438 payment_hash: PaymentHash,
439 /// The payment path that was successful.
442 /// Indicates that a probe payment we sent failed at an intermediary node on the path.
444 /// The id returned by [`ChannelManager::send_probe`].
446 /// [`ChannelManager::send_probe`]: crate::ln::channelmanager::ChannelManager::send_probe
447 payment_id: PaymentId,
448 /// The hash generated by [`ChannelManager::send_probe`].
450 /// [`ChannelManager::send_probe`]: crate::ln::channelmanager::ChannelManager::send_probe
451 payment_hash: PaymentHash,
452 /// The payment path that failed.
454 /// The channel responsible for the failed probe.
456 /// Note that for route hints or for the first hop in a path this may be an SCID alias and
457 /// may not refer to a channel in the public network graph. These aliases may also collide
458 /// with channels in the public network graph.
459 short_channel_id: Option<u64>,
461 /// Used to indicate that [`ChannelManager::process_pending_htlc_forwards`] should be called at
462 /// a time in the future.
464 /// [`ChannelManager::process_pending_htlc_forwards`]: crate::ln::channelmanager::ChannelManager::process_pending_htlc_forwards
465 PendingHTLCsForwardable {
466 /// The minimum amount of time that should be waited prior to calling
467 /// process_pending_htlc_forwards. To increase the effort required to correlate payments,
468 /// you should wait a random amount of time in roughly the range (now + time_forwardable,
469 /// now + 5*time_forwardable).
470 time_forwardable: Duration,
472 /// Used to indicate that an output which you should know how to spend was confirmed on chain
473 /// and is now spendable.
474 /// Such an output will *not* ever be spent by rust-lightning, and are not at risk of your
475 /// counterparty spending them due to some kind of timeout. Thus, you need to store them
476 /// somewhere and spend them when you create on-chain transactions.
478 /// The outputs which you should store as spendable by you.
479 outputs: Vec<SpendableOutputDescriptor>,
481 /// This event is generated when a payment has been successfully forwarded through us and a
482 /// forwarding fee earned.
484 /// The incoming channel between the previous node and us. This is only `None` for events
485 /// generated or serialized by versions prior to 0.0.107.
486 prev_channel_id: Option<[u8; 32]>,
487 /// The outgoing channel between the next node and us. This is only `None` for events
488 /// generated or serialized by versions prior to 0.0.107.
489 next_channel_id: Option<[u8; 32]>,
490 /// The fee, in milli-satoshis, which was earned as a result of the payment.
492 /// Note that if we force-closed the channel over which we forwarded an HTLC while the HTLC
493 /// was pending, the amount the next hop claimed will have been rounded down to the nearest
494 /// whole satoshi. Thus, the fee calculated here may be higher than expected as we still
495 /// claimed the full value in millisatoshis from the source. In this case,
496 /// `claim_from_onchain_tx` will be set.
498 /// If the channel which sent us the payment has been force-closed, we will claim the funds
499 /// via an on-chain transaction. In that case we do not yet know the on-chain transaction
500 /// fees which we will spend and will instead set this to `None`. It is possible duplicate
501 /// `PaymentForwarded` events are generated for the same payment iff `fee_earned_msat` is
503 fee_earned_msat: Option<u64>,
504 /// If this is `true`, the forwarded HTLC was claimed by our counterparty via an on-chain
506 claim_from_onchain_tx: bool,
508 /// Used to indicate that a previously opened channel with the given `channel_id` is in the
509 /// process of closure.
511 /// The channel_id of the channel which has been closed. Note that on-chain transactions
512 /// resolving the channel are likely still awaiting confirmation.
513 channel_id: [u8; 32],
514 /// The `user_channel_id` value passed in to [`ChannelManager::create_channel`] for outbound
515 /// channels, or to [`ChannelManager::accept_inbound_channel`] for inbound channels if
516 /// [`UserConfig::manually_accept_inbound_channels`] config flag is set to true. Otherwise
517 /// `user_channel_id` will be 0 for an inbound channel.
518 /// This will always be zero for objects serialized with LDK versions prior to 0.0.102.
520 /// [`ChannelManager::create_channel`]: crate::ln::channelmanager::ChannelManager::create_channel
521 /// [`ChannelManager::accept_inbound_channel`]: crate::ln::channelmanager::ChannelManager::accept_inbound_channel
522 /// [`UserConfig::manually_accept_inbound_channels`]: crate::util::config::UserConfig::manually_accept_inbound_channels
523 user_channel_id: u64,
524 /// The reason the channel was closed.
525 reason: ClosureReason
527 /// Used to indicate to the user that they can abandon the funding transaction and recycle the
528 /// inputs for another purpose.
530 /// The channel_id of the channel which has been closed.
531 channel_id: [u8; 32],
532 /// The full transaction received from the user
533 transaction: Transaction
535 /// Indicates a request to open a new channel by a peer.
537 /// To accept the request, call [`ChannelManager::accept_inbound_channel`]. To reject the
538 /// request, call [`ChannelManager::force_close_without_broadcasting_txn`].
540 /// The event is only triggered when a new open channel request is received and the
541 /// [`UserConfig::manually_accept_inbound_channels`] config flag is set to true.
543 /// [`ChannelManager::accept_inbound_channel`]: crate::ln::channelmanager::ChannelManager::accept_inbound_channel
544 /// [`ChannelManager::force_close_without_broadcasting_txn`]: crate::ln::channelmanager::ChannelManager::force_close_without_broadcasting_txn
545 /// [`UserConfig::manually_accept_inbound_channels`]: crate::util::config::UserConfig::manually_accept_inbound_channels
547 /// The temporary channel ID of the channel requested to be opened.
549 /// When responding to the request, the `temporary_channel_id` should be passed
550 /// back to the ChannelManager through [`ChannelManager::accept_inbound_channel`] to accept,
551 /// or through [`ChannelManager::force_close_without_broadcasting_txn`] to reject.
553 /// [`ChannelManager::accept_inbound_channel`]: crate::ln::channelmanager::ChannelManager::accept_inbound_channel
554 /// [`ChannelManager::force_close_without_broadcasting_txn`]: crate::ln::channelmanager::ChannelManager::force_close_without_broadcasting_txn
555 temporary_channel_id: [u8; 32],
556 /// The node_id of the counterparty requesting to open the channel.
558 /// When responding to the request, the `counterparty_node_id` should be passed
559 /// back to the `ChannelManager` through [`ChannelManager::accept_inbound_channel`] to
560 /// accept the request, or through [`ChannelManager::force_close_without_broadcasting_txn`] to reject the
563 /// [`ChannelManager::accept_inbound_channel`]: crate::ln::channelmanager::ChannelManager::accept_inbound_channel
564 /// [`ChannelManager::force_close_without_broadcasting_txn`]: crate::ln::channelmanager::ChannelManager::force_close_without_broadcasting_txn
565 counterparty_node_id: PublicKey,
566 /// The channel value of the requested channel.
567 funding_satoshis: u64,
568 /// Our starting balance in the channel if the request is accepted, in milli-satoshi.
570 /// The features that this channel will operate with. If you reject the channel, a
571 /// well-behaved counterparty may automatically re-attempt the channel with a new set of
574 /// Note that if [`ChannelTypeFeatures::supports_scid_privacy`] returns true on this type,
575 /// the resulting [`ChannelManager`] will not be readable by versions of LDK prior to
578 /// Furthermore, note that if [`ChannelTypeFeatures::supports_zero_conf`] returns true on this type,
579 /// the resulting [`ChannelManager`] will not be readable by versions of LDK prior to
580 /// 0.0.107. Channels setting this type also need to get manually accepted via
581 /// [`crate::ln::channelmanager::ChannelManager::accept_inbound_channel_from_trusted_peer_0conf`],
582 /// or will be rejected otherwise.
584 /// [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
585 channel_type: ChannelTypeFeatures,
587 /// Indicates that the HTLC was accepted, but could not be processed when or after attempting to
590 /// Some scenarios where this event may be sent include:
591 /// * Insufficient capacity in the outbound channel
592 /// * While waiting to forward the HTLC, the channel it is meant to be forwarded through closes
593 /// * When an unknown SCID is requested for forwarding a payment.
594 /// * Claiming an amount for an MPP payment that exceeds the HTLC total
595 /// * The HTLC has timed out
597 /// This event, however, does not get generated if an HTLC fails to meet the forwarding
598 /// requirements (i.e. insufficient fees paid, or a CLTV that is too soon).
600 /// The channel over which the HTLC was received.
601 prev_channel_id: [u8; 32],
602 /// Destination of the HTLC that failed to be processed.
603 failed_next_destination: HTLCDestination,
607 impl Writeable for Event {
608 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
610 &Event::FundingGenerationReady { .. } => {
612 // We never write out FundingGenerationReady events as, upon disconnection, peers
613 // drop any channels which have not yet exchanged funding_signed.
615 &Event::PaymentReceived { ref payment_hash, ref amount_msat, ref purpose } => {
617 let mut payment_secret = None;
618 let payment_preimage;
620 PaymentPurpose::InvoicePayment { payment_preimage: preimage, payment_secret: secret } => {
621 payment_secret = Some(secret);
622 payment_preimage = *preimage;
624 PaymentPurpose::SpontaneousPayment(preimage) => {
625 payment_preimage = Some(*preimage);
628 write_tlv_fields!(writer, {
629 (0, payment_hash, required),
630 (2, payment_secret, option),
631 (4, amount_msat, required),
632 (6, 0u64, required), // user_payment_id required for compatibility with 0.0.103 and earlier
633 (8, payment_preimage, option),
636 &Event::PaymentSent { ref payment_id, ref payment_preimage, ref payment_hash, ref fee_paid_msat } => {
638 write_tlv_fields!(writer, {
639 (0, payment_preimage, required),
640 (1, payment_hash, required),
641 (3, payment_id, option),
642 (5, fee_paid_msat, option),
645 &Event::PaymentPathFailed {
646 ref payment_id, ref payment_hash, ref rejected_by_dest, ref network_update,
647 ref all_paths_failed, ref path, ref short_channel_id, ref retry,
655 error_code.write(writer)?;
657 error_data.write(writer)?;
658 write_tlv_fields!(writer, {
659 (0, payment_hash, required),
660 (1, network_update, option),
661 (2, rejected_by_dest, required),
662 (3, all_paths_failed, required),
664 (7, short_channel_id, option),
666 (11, payment_id, option),
669 &Event::PendingHTLCsForwardable { time_forwardable: _ } => {
671 // Note that we now ignore these on the read end as we'll re-generate them in
672 // ChannelManager, we write them here only for backwards compatibility.
674 &Event::SpendableOutputs { ref outputs } => {
676 write_tlv_fields!(writer, {
677 (0, VecWriteWrapper(outputs), required),
680 &Event::PaymentForwarded { fee_earned_msat, prev_channel_id, claim_from_onchain_tx, next_channel_id } => {
682 write_tlv_fields!(writer, {
683 (0, fee_earned_msat, option),
684 (1, prev_channel_id, option),
685 (2, claim_from_onchain_tx, required),
686 (3, next_channel_id, option),
689 &Event::ChannelClosed { ref channel_id, ref user_channel_id, ref reason } => {
691 write_tlv_fields!(writer, {
692 (0, channel_id, required),
693 (1, user_channel_id, required),
694 (2, reason, required)
697 &Event::DiscardFunding { ref channel_id, ref transaction } => {
699 write_tlv_fields!(writer, {
700 (0, channel_id, required),
701 (2, transaction, required)
704 &Event::PaymentPathSuccessful { ref payment_id, ref payment_hash, ref path } => {
706 write_tlv_fields!(writer, {
707 (0, payment_id, required),
708 (2, payment_hash, option),
712 &Event::PaymentFailed { ref payment_id, ref payment_hash } => {
714 write_tlv_fields!(writer, {
715 (0, payment_id, required),
716 (2, payment_hash, required),
719 &Event::OpenChannelRequest { .. } => {
721 // We never write the OpenChannelRequest events as, upon disconnection, peers
722 // drop any channels which have not yet exchanged funding_signed.
724 &Event::PaymentClaimed { ref payment_hash, ref amount_msat, ref purpose } => {
726 write_tlv_fields!(writer, {
727 (0, payment_hash, required),
728 (2, purpose, required),
729 (4, amount_msat, required),
732 &Event::ProbeSuccessful { ref payment_id, ref payment_hash, ref path } => {
734 write_tlv_fields!(writer, {
735 (0, payment_id, required),
736 (2, payment_hash, required),
740 &Event::ProbeFailed { ref payment_id, ref payment_hash, ref path, ref short_channel_id } => {
742 write_tlv_fields!(writer, {
743 (0, payment_id, required),
744 (2, payment_hash, required),
746 (6, short_channel_id, option),
749 &Event::HTLCHandlingFailed { ref prev_channel_id, ref failed_next_destination } => {
751 write_tlv_fields!(writer, {
752 (0, prev_channel_id, required),
753 (2, failed_next_destination, required),
756 // Note that, going forward, all new events must only write data inside of
757 // `write_tlv_fields`. Versions 0.0.101+ will ignore odd-numbered events that write
758 // data via `write_tlv_fields`.
763 impl MaybeReadable for Event {
764 fn read<R: io::Read>(reader: &mut R) -> Result<Option<Self>, msgs::DecodeError> {
765 match Readable::read(reader)? {
766 // Note that we do not write a length-prefixed TLV for FundingGenerationReady events,
767 // unlike all other events, thus we return immediately here.
771 let mut payment_hash = PaymentHash([0; 32]);
772 let mut payment_preimage = None;
773 let mut payment_secret = None;
774 let mut amount_msat = 0;
775 let mut _user_payment_id = None::<u64>; // For compatibility with 0.0.103 and earlier
776 read_tlv_fields!(reader, {
777 (0, payment_hash, required),
778 (2, payment_secret, option),
779 (4, amount_msat, required),
780 (6, _user_payment_id, option),
781 (8, payment_preimage, option),
783 let purpose = match payment_secret {
784 Some(secret) => PaymentPurpose::InvoicePayment {
786 payment_secret: secret
788 None if payment_preimage.is_some() => PaymentPurpose::SpontaneousPayment(payment_preimage.unwrap()),
789 None => return Err(msgs::DecodeError::InvalidValue),
791 Ok(Some(Event::PaymentReceived {
801 let mut payment_preimage = PaymentPreimage([0; 32]);
802 let mut payment_hash = None;
803 let mut payment_id = None;
804 let mut fee_paid_msat = None;
805 read_tlv_fields!(reader, {
806 (0, payment_preimage, required),
807 (1, payment_hash, option),
808 (3, payment_id, option),
809 (5, fee_paid_msat, option),
811 if payment_hash.is_none() {
812 payment_hash = Some(PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()));
814 Ok(Some(Event::PaymentSent {
817 payment_hash: payment_hash.unwrap(),
826 let error_code = Readable::read(reader)?;
828 let error_data = Readable::read(reader)?;
829 let mut payment_hash = PaymentHash([0; 32]);
830 let mut rejected_by_dest = false;
831 let mut network_update = None;
832 let mut all_paths_failed = Some(true);
833 let mut path: Option<Vec<RouteHop>> = Some(vec![]);
834 let mut short_channel_id = None;
835 let mut retry = None;
836 let mut payment_id = None;
837 read_tlv_fields!(reader, {
838 (0, payment_hash, required),
839 (1, network_update, ignorable),
840 (2, rejected_by_dest, required),
841 (3, all_paths_failed, option),
843 (7, short_channel_id, option),
845 (11, payment_id, option),
847 Ok(Some(Event::PaymentPathFailed {
852 all_paths_failed: all_paths_failed.unwrap(),
867 let mut outputs = VecReadWrapper(Vec::new());
868 read_tlv_fields!(reader, {
869 (0, outputs, required),
871 Ok(Some(Event::SpendableOutputs { outputs: outputs.0 }))
877 let mut fee_earned_msat = None;
878 let mut prev_channel_id = None;
879 let mut claim_from_onchain_tx = false;
880 let mut next_channel_id = None;
881 read_tlv_fields!(reader, {
882 (0, fee_earned_msat, option),
883 (1, prev_channel_id, option),
884 (2, claim_from_onchain_tx, required),
885 (3, next_channel_id, option),
887 Ok(Some(Event::PaymentForwarded { fee_earned_msat, prev_channel_id, claim_from_onchain_tx, next_channel_id }))
893 let mut channel_id = [0; 32];
894 let mut reason = None;
895 let mut user_channel_id_opt = None;
896 read_tlv_fields!(reader, {
897 (0, channel_id, required),
898 (1, user_channel_id_opt, option),
899 (2, reason, ignorable),
901 if reason.is_none() { return Ok(None); }
902 let user_channel_id = if let Some(id) = user_channel_id_opt { id } else { 0 };
903 Ok(Some(Event::ChannelClosed { channel_id, user_channel_id, reason: reason.unwrap() }))
909 let mut channel_id = [0; 32];
910 let mut transaction = Transaction{ version: 2, lock_time: 0, input: Vec::new(), output: Vec::new() };
911 read_tlv_fields!(reader, {
912 (0, channel_id, required),
913 (2, transaction, required),
915 Ok(Some(Event::DiscardFunding { channel_id, transaction } ))
921 let mut payment_id = PaymentId([0; 32]);
922 let mut payment_hash = None;
923 let mut path: Option<Vec<RouteHop>> = Some(vec![]);
924 read_tlv_fields!(reader, {
925 (0, payment_id, required),
926 (2, payment_hash, option),
929 Ok(Some(Event::PaymentPathSuccessful {
939 let mut payment_hash = PaymentHash([0; 32]);
940 let mut payment_id = PaymentId([0; 32]);
941 read_tlv_fields!(reader, {
942 (0, payment_id, required),
943 (2, payment_hash, required),
945 Ok(Some(Event::PaymentFailed {
953 // Value 17 is used for `Event::OpenChannelRequest`.
958 let mut payment_hash = PaymentHash([0; 32]);
959 let mut purpose = None;
960 let mut amount_msat = 0;
961 read_tlv_fields!(reader, {
962 (0, payment_hash, required),
963 (2, purpose, ignorable),
964 (4, amount_msat, required),
966 if purpose.is_none() { return Ok(None); }
967 Ok(Some(Event::PaymentClaimed {
969 purpose: purpose.unwrap(),
977 let mut payment_id = PaymentId([0; 32]);
978 let mut payment_hash = PaymentHash([0; 32]);
979 let mut path: Option<Vec<RouteHop>> = Some(vec![]);
980 read_tlv_fields!(reader, {
981 (0, payment_id, required),
982 (2, payment_hash, required),
985 Ok(Some(Event::ProbeSuccessful {
995 let mut payment_id = PaymentId([0; 32]);
996 let mut payment_hash = PaymentHash([0; 32]);
997 let mut path: Option<Vec<RouteHop>> = Some(vec![]);
998 let mut short_channel_id = None;
999 read_tlv_fields!(reader, {
1000 (0, payment_id, required),
1001 (2, payment_hash, required),
1002 (4, path, vec_type),
1003 (6, short_channel_id, option),
1005 Ok(Some(Event::ProbeFailed{
1008 path: path.unwrap(),
1014 // Versions prior to 0.0.100 did not ignore odd types, instead returning InvalidValue.
1015 // Version 0.0.100 failed to properly ignore odd types, possibly resulting in corrupt
1017 x if x % 2 == 1 => {
1018 // If the event is of unknown type, assume it was written with `write_tlv_fields`,
1019 // which prefixes the whole thing with a length BigSize. Because the event is
1020 // odd-type unknown, we should treat it as `Ok(None)` even if it has some TLV
1021 // fields that are even. Thus, we avoid using `read_tlv_fields` and simply read
1022 // exactly the number of bytes specified, ignoring them entirely.
1023 let tlv_len: BigSize = Readable::read(reader)?;
1024 FixedLengthReader::new(reader, tlv_len.0)
1025 .eat_remaining().map_err(|_| msgs::DecodeError::ShortRead)?;
1028 _ => Err(msgs::DecodeError::InvalidValue)
1033 /// An event generated by ChannelManager which indicates a message should be sent to a peer (or
1034 /// broadcast to most peers).
1035 /// These events are handled by PeerManager::process_events if you are using a PeerManager.
1036 #[derive(Clone, Debug)]
1037 pub enum MessageSendEvent {
1038 /// Used to indicate that we've accepted a channel open and should send the accept_channel
1039 /// message provided to the given peer.
1041 /// The node_id of the node which should receive this message
1043 /// The message which should be sent.
1044 msg: msgs::AcceptChannel,
1046 /// Used to indicate that we've initiated a channel open and should send the open_channel
1047 /// message provided to the given peer.
1049 /// The node_id of the node which should receive this message
1051 /// The message which should be sent.
1052 msg: msgs::OpenChannel,
1054 /// Used to indicate that a funding_created message should be sent to the peer with the given node_id.
1055 SendFundingCreated {
1056 /// The node_id of the node which should receive this message
1058 /// The message which should be sent.
1059 msg: msgs::FundingCreated,
1061 /// Used to indicate that a funding_signed message should be sent to the peer with the given node_id.
1063 /// The node_id of the node which should receive this message
1065 /// The message which should be sent.
1066 msg: msgs::FundingSigned,
1068 /// Used to indicate that a channel_ready message should be sent to the peer with the given node_id.
1070 /// The node_id of the node which should receive these message(s)
1072 /// The channel_ready message which should be sent.
1073 msg: msgs::ChannelReady,
1075 /// Used to indicate that an announcement_signatures message should be sent to the peer with the given node_id.
1076 SendAnnouncementSignatures {
1077 /// The node_id of the node which should receive these message(s)
1079 /// The announcement_signatures message which should be sent.
1080 msg: msgs::AnnouncementSignatures,
1082 /// Used to indicate that a series of HTLC update messages, as well as a commitment_signed
1083 /// message should be sent to the peer with the given node_id.
1085 /// The node_id of the node which should receive these message(s)
1087 /// The update messages which should be sent. ALL messages in the struct should be sent!
1088 updates: msgs::CommitmentUpdate,
1090 /// Used to indicate that a revoke_and_ack message should be sent to the peer with the given node_id.
1092 /// The node_id of the node which should receive this message
1094 /// The message which should be sent.
1095 msg: msgs::RevokeAndACK,
1097 /// Used to indicate that a closing_signed message should be sent to the peer with the given node_id.
1099 /// The node_id of the node which should receive this message
1101 /// The message which should be sent.
1102 msg: msgs::ClosingSigned,
1104 /// Used to indicate that a shutdown message should be sent to the peer with the given node_id.
1106 /// The node_id of the node which should receive this message
1108 /// The message which should be sent.
1109 msg: msgs::Shutdown,
1111 /// Used to indicate that a channel_reestablish message should be sent to the peer with the given node_id.
1112 SendChannelReestablish {
1113 /// The node_id of the node which should receive this message
1115 /// The message which should be sent.
1116 msg: msgs::ChannelReestablish,
1118 /// Used to indicate that a channel_announcement and channel_update should be broadcast to all
1119 /// peers (except the peer with node_id either msg.contents.node_id_1 or msg.contents.node_id_2).
1121 /// Note that after doing so, you very likely (unless you did so very recently) want to call
1122 /// ChannelManager::broadcast_node_announcement to trigger a BroadcastNodeAnnouncement event.
1123 /// This ensures that any nodes which see our channel_announcement also have a relevant
1124 /// node_announcement, including relevant feature flags which may be important for routing
1125 /// through or to us.
1126 BroadcastChannelAnnouncement {
1127 /// The channel_announcement which should be sent.
1128 msg: msgs::ChannelAnnouncement,
1129 /// The followup channel_update which should be sent.
1130 update_msg: msgs::ChannelUpdate,
1132 /// Used to indicate that a node_announcement should be broadcast to all peers.
1133 BroadcastNodeAnnouncement {
1134 /// The node_announcement which should be sent.
1135 msg: msgs::NodeAnnouncement,
1137 /// Used to indicate that a channel_update should be broadcast to all peers.
1138 BroadcastChannelUpdate {
1139 /// The channel_update which should be sent.
1140 msg: msgs::ChannelUpdate,
1142 /// Used to indicate that a channel_update should be sent to a single peer.
1143 /// In contrast to [`Self::BroadcastChannelUpdate`], this is used when the channel is a
1144 /// private channel and we shouldn't be informing all of our peers of channel parameters.
1146 /// The node_id of the node which should receive this message
1148 /// The channel_update which should be sent.
1149 msg: msgs::ChannelUpdate,
1151 /// Broadcast an error downstream to be handled
1153 /// The node_id of the node which should receive this message
1155 /// The action which should be taken.
1156 action: msgs::ErrorAction
1158 /// Query a peer for channels with funding transaction UTXOs in a block range.
1159 SendChannelRangeQuery {
1160 /// The node_id of this message recipient
1162 /// The query_channel_range which should be sent.
1163 msg: msgs::QueryChannelRange,
1165 /// Request routing gossip messages from a peer for a list of channels identified by
1166 /// their short_channel_ids.
1168 /// The node_id of this message recipient
1170 /// The query_short_channel_ids which should be sent.
1171 msg: msgs::QueryShortChannelIds,
1173 /// Sends a reply to a channel range query. This may be one of several SendReplyChannelRange events
1174 /// emitted during processing of the query.
1175 SendReplyChannelRange {
1176 /// The node_id of this message recipient
1178 /// The reply_channel_range which should be sent.
1179 msg: msgs::ReplyChannelRange,
1181 /// Sends a timestamp filter for inbound gossip. This should be sent on each new connection to
1182 /// enable receiving gossip messages from the peer.
1183 SendGossipTimestampFilter {
1184 /// The node_id of this message recipient
1186 /// The gossip_timestamp_filter which should be sent.
1187 msg: msgs::GossipTimestampFilter,
1191 /// A trait indicating an object may generate message send events
1192 pub trait MessageSendEventsProvider {
1193 /// Gets the list of pending events which were generated by previous actions, clearing the list
1195 fn get_and_clear_pending_msg_events(&self) -> Vec<MessageSendEvent>;
1198 /// A trait indicating an object may generate events.
1200 /// Events are processed by passing an [`EventHandler`] to [`process_pending_events`].
1204 /// See [`process_pending_events`] for requirements around event processing.
1206 /// When using this trait, [`process_pending_events`] will call [`handle_event`] for each pending
1207 /// event since the last invocation. The handler must either act upon the event immediately
1208 /// or preserve it for later handling.
1210 /// Note, handlers may call back into the provider and thus deadlocking must be avoided. Be sure to
1211 /// consult the provider's documentation on the implication of processing events and how a handler
1212 /// may safely use the provider (e.g., see [`ChannelManager::process_pending_events`] and
1213 /// [`ChainMonitor::process_pending_events`]).
1215 /// (C-not implementable) As there is likely no reason for a user to implement this trait on their
1218 /// [`process_pending_events`]: Self::process_pending_events
1219 /// [`handle_event`]: EventHandler::handle_event
1220 /// [`ChannelManager::process_pending_events`]: crate::ln::channelmanager::ChannelManager#method.process_pending_events
1221 /// [`ChainMonitor::process_pending_events`]: crate::chain::chainmonitor::ChainMonitor#method.process_pending_events
1222 pub trait EventsProvider {
1223 /// Processes any events generated since the last call using the given event handler.
1225 /// Subsequent calls must only process new events. However, handlers must be capable of handling
1226 /// duplicate events across process restarts. This may occur if the provider was recovered from
1227 /// an old state (i.e., it hadn't been successfully persisted after processing pending events).
1228 fn process_pending_events<H: Deref>(&self, handler: H) where H::Target: EventHandler;
1231 /// A trait implemented for objects handling events from [`EventsProvider`].
1232 pub trait EventHandler {
1233 /// Handles the given [`Event`].
1235 /// See [`EventsProvider`] for details that must be considered when implementing this method.
1236 fn handle_event(&self, event: &Event);
1239 impl<F> EventHandler for F where F: Fn(&Event) {
1240 fn handle_event(&self, event: &Event) {
1245 impl<T: EventHandler> EventHandler for Arc<T> {
1246 fn handle_event(&self, event: &Event) {
1247 self.deref().handle_event(event)