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 crate::chain::keysinterface::SpendableOutputDescriptor;
19 use crate::ln::chan_utils::{self, ChannelTransactionParameters, HTLCOutputInCommitment};
20 use crate::ln::channelmanager::{InterceptId, PaymentId};
21 use crate::ln::channel::FUNDING_CONF_DEADLINE_BLOCKS;
22 use crate::ln::features::ChannelTypeFeatures;
24 use crate::ln::{PaymentPreimage, PaymentHash, PaymentSecret};
25 use crate::routing::gossip::NetworkUpdate;
26 use crate::util::errors::APIError;
27 use crate::util::ser::{BigSize, FixedLengthReader, Writeable, Writer, MaybeReadable, Readable, RequiredWrapper, UpgradableRequired, WithoutLength};
28 use crate::routing::router::{RouteHop, RouteParameters};
30 use bitcoin::{PackedLockTime, Transaction};
32 use bitcoin::{OutPoint, Txid, TxIn, TxOut, Witness};
33 use bitcoin::blockdata::script::Script;
34 use bitcoin::hashes::Hash;
35 use bitcoin::hashes::sha256::Hash as Sha256;
36 use bitcoin::secp256k1::PublicKey;
38 use bitcoin::secp256k1::{self, Secp256k1};
40 use bitcoin::secp256k1::ecdsa::Signature;
42 use crate::prelude::*;
43 use core::time::Duration;
47 /// Some information provided on receipt of payment depends on whether the payment received is a
48 /// spontaneous payment or a "conventional" lightning payment that's paying an invoice.
49 #[derive(Clone, Debug, PartialEq, Eq)]
50 pub enum PaymentPurpose {
51 /// Information for receiving a payment that we generated an invoice for.
53 /// The preimage to the payment_hash, if the payment hash (and secret) were fetched via
54 /// [`ChannelManager::create_inbound_payment`]. If provided, this can be handed directly to
55 /// [`ChannelManager::claim_funds`].
57 /// [`ChannelManager::create_inbound_payment`]: crate::ln::channelmanager::ChannelManager::create_inbound_payment
58 /// [`ChannelManager::claim_funds`]: crate::ln::channelmanager::ChannelManager::claim_funds
59 payment_preimage: Option<PaymentPreimage>,
60 /// The "payment secret". This authenticates the sender to the recipient, preventing a
61 /// number of deanonymization attacks during the routing process.
62 /// It is provided here for your reference, however its accuracy is enforced directly by
63 /// [`ChannelManager`] using the values you previously provided to
64 /// [`ChannelManager::create_inbound_payment`] or
65 /// [`ChannelManager::create_inbound_payment_for_hash`].
67 /// [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
68 /// [`ChannelManager::create_inbound_payment`]: crate::ln::channelmanager::ChannelManager::create_inbound_payment
69 /// [`ChannelManager::create_inbound_payment_for_hash`]: crate::ln::channelmanager::ChannelManager::create_inbound_payment_for_hash
70 payment_secret: PaymentSecret,
72 /// Because this is a spontaneous payment, the payer generated their own preimage rather than us
73 /// (the payee) providing a preimage.
74 SpontaneousPayment(PaymentPreimage),
77 impl_writeable_tlv_based_enum!(PaymentPurpose,
78 (0, InvoicePayment) => {
79 (0, payment_preimage, option),
80 (2, payment_secret, required),
82 (2, SpontaneousPayment)
85 /// When the payment path failure took place and extra details about it. [`PathFailure::OnPath`] may
86 /// contain a [`NetworkUpdate`] that needs to be applied to the [`NetworkGraph`].
88 /// [`NetworkUpdate`]: crate::routing::gossip::NetworkUpdate
89 /// [`NetworkGraph`]: crate::routing::gossip::NetworkGraph
90 #[derive(Clone, Debug, Eq, PartialEq)]
91 pub enum PathFailure {
92 /// We failed to initially send the payment and no HTLC was committed to. Contains the relevant
95 /// The error surfaced from initial send.
98 /// A hop on the path failed to forward our payment.
100 /// If present, this [`NetworkUpdate`] should be applied to the [`NetworkGraph`] so that routing
101 /// decisions can take into account the update.
103 /// [`NetworkUpdate`]: crate::routing::gossip::NetworkUpdate
104 /// [`NetworkGraph`]: crate::routing::gossip::NetworkGraph
105 network_update: Option<NetworkUpdate>,
109 impl_writeable_tlv_based_enum_upgradable!(PathFailure,
111 (0, network_update, upgradable_option),
113 (2, InitialSend) => {
114 (0, err, upgradable_required),
118 #[derive(Clone, Debug, PartialEq, Eq)]
119 /// The reason the channel was closed. See individual variants more details.
120 pub enum ClosureReason {
121 /// Closure generated from receiving a peer error message.
123 /// Our counterparty may have broadcasted their latest commitment state, and we have
125 CounterpartyForceClosed {
126 /// The error which the peer sent us.
128 /// The string should be sanitized before it is used (e.g emitted to logs
129 /// or printed to stdout). Otherwise, a well crafted error message may exploit
130 /// a security vulnerability in the terminal emulator or the logging subsystem.
133 /// Closure generated from [`ChannelManager::force_close_channel`], called by the user.
135 /// [`ChannelManager::force_close_channel`]: crate::ln::channelmanager::ChannelManager::force_close_channel.
137 /// The channel was closed after negotiating a cooperative close and we've now broadcasted
138 /// the cooperative close transaction. Note the shutdown may have been initiated by us.
139 //TODO: split between CounterpartyInitiated/LocallyInitiated
141 /// A commitment transaction was confirmed on chain, closing the channel. Most likely this
142 /// commitment transaction came from our counterparty, but it may also have come from
143 /// a copy of our own `ChannelMonitor`.
144 CommitmentTxConfirmed,
145 /// The funding transaction failed to confirm in a timely manner on an inbound channel.
147 /// Closure generated from processing an event, likely a HTLC forward/relay/reception.
149 /// A developer-readable error message which we generated.
152 /// The peer disconnected prior to funding completing. In this case the spec mandates that we
153 /// forget the channel entirely - we can attempt again if the peer reconnects.
155 /// This includes cases where we restarted prior to funding completion, including prior to the
156 /// initial [`ChannelMonitor`] persistence completing.
158 /// In LDK versions prior to 0.0.107 this could also occur if we were unable to connect to the
159 /// peer because of mutual incompatibility between us and our channel counterparty.
161 /// [`ChannelMonitor`]: crate::chain::channelmonitor::ChannelMonitor
163 /// Closure generated from `ChannelManager::read` if the [`ChannelMonitor`] is newer than
164 /// the [`ChannelManager`] deserialized.
166 /// [`ChannelMonitor`]: crate::chain::channelmonitor::ChannelMonitor
167 /// [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
168 OutdatedChannelManager
171 impl core::fmt::Display for ClosureReason {
172 fn fmt(&self, f: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {
173 f.write_str("Channel closed because ")?;
175 ClosureReason::CounterpartyForceClosed { peer_msg } => {
176 f.write_str("counterparty force-closed with message ")?;
177 f.write_str(&peer_msg)
179 ClosureReason::HolderForceClosed => f.write_str("user manually force-closed the channel"),
180 ClosureReason::CooperativeClosure => f.write_str("the channel was cooperatively closed"),
181 ClosureReason::CommitmentTxConfirmed => f.write_str("commitment or closing transaction was confirmed on chain."),
182 ClosureReason::FundingTimedOut => write!(f, "funding transaction failed to confirm within {} blocks", FUNDING_CONF_DEADLINE_BLOCKS),
183 ClosureReason::ProcessingError { err } => {
184 f.write_str("of an exception: ")?;
187 ClosureReason::DisconnectedPeer => f.write_str("the peer disconnected prior to the channel being funded"),
188 ClosureReason::OutdatedChannelManager => f.write_str("the ChannelManager read from disk was stale compared to ChannelMonitor(s)"),
193 impl_writeable_tlv_based_enum_upgradable!(ClosureReason,
194 (0, CounterpartyForceClosed) => { (1, peer_msg, required) },
195 (1, FundingTimedOut) => {},
196 (2, HolderForceClosed) => {},
197 (6, CommitmentTxConfirmed) => {},
198 (4, CooperativeClosure) => {},
199 (8, ProcessingError) => { (1, err, required) },
200 (10, DisconnectedPeer) => {},
201 (12, OutdatedChannelManager) => {},
204 /// Intended destination of a failed HTLC as indicated in [`Event::HTLCHandlingFailed`].
205 #[derive(Clone, Debug, PartialEq, Eq)]
206 pub enum HTLCDestination {
207 /// We tried forwarding to a channel but failed to do so. An example of such an instance is when
208 /// there is insufficient capacity in our outbound channel.
210 /// The `node_id` of the next node. For backwards compatibility, this field is
211 /// marked as optional, versions prior to 0.0.110 may not always be able to provide
212 /// counterparty node information.
213 node_id: Option<PublicKey>,
214 /// The outgoing `channel_id` between us and the next node.
215 channel_id: [u8; 32],
217 /// Scenario where we are unsure of the next node to forward the HTLC to.
219 /// Short channel id we are requesting to forward an HTLC to.
220 requested_forward_scid: u64,
222 /// We couldn't forward to the outgoing scid. An example would be attempting to send a duplicate
225 /// Short channel id we are requesting to forward an HTLC to.
226 requested_forward_scid: u64
228 /// Failure scenario where an HTLC may have been forwarded to be intended for us,
229 /// but is invalid for some reason, so we reject it.
231 /// Some of the reasons may include:
233 /// * Expected MPP amount to claim does not equal HTLC total
234 /// * Claimable amount does not match expected amount
236 /// The payment hash of the payment we attempted to process.
237 payment_hash: PaymentHash
241 impl_writeable_tlv_based_enum_upgradable!(HTLCDestination,
242 (0, NextHopChannel) => {
243 (0, node_id, required),
244 (2, channel_id, required),
246 (1, InvalidForward) => {
247 (0, requested_forward_scid, required),
249 (2, UnknownNextHop) => {
250 (0, requested_forward_scid, required),
252 (4, FailedPayment) => {
253 (0, payment_hash, required),
258 /// A descriptor used to sign for a commitment transaction's anchor output.
259 #[derive(Clone, Debug, PartialEq, Eq)]
260 pub struct AnchorDescriptor {
261 /// A unique identifier used along with `channel_value_satoshis` to re-derive the
262 /// [`InMemorySigner`] required to sign `input`.
264 /// [`InMemorySigner`]: crate::chain::keysinterface::InMemorySigner
265 pub channel_keys_id: [u8; 32],
266 /// The value in satoshis of the channel we're attempting to spend the anchor output of. This is
267 /// used along with `channel_keys_id` to re-derive the [`InMemorySigner`] required to sign
270 /// [`InMemorySigner`]: crate::chain::keysinterface::InMemorySigner
271 pub channel_value_satoshis: u64,
272 /// The transaction input's outpoint corresponding to the commitment transaction's anchor
274 pub outpoint: OutPoint,
278 /// A descriptor used to sign for a commitment transaction's HTLC output.
279 #[derive(Clone, Debug, PartialEq, Eq)]
280 pub struct HTLCDescriptor {
281 /// A unique identifier used along with `channel_value_satoshis` to re-derive the
282 /// [`InMemorySigner`] required to sign `input`.
284 /// [`InMemorySigner`]: crate::chain::keysinterface::InMemorySigner
285 pub channel_keys_id: [u8; 32],
286 /// The value in satoshis of the channel we're attempting to spend the anchor output of. This is
287 /// used along with `channel_keys_id` to re-derive the [`InMemorySigner`] required to sign
290 /// [`InMemorySigner`]: crate::chain::keysinterface::InMemorySigner
291 pub channel_value_satoshis: u64,
292 /// The necessary channel parameters that need to be provided to the re-derived
293 /// [`InMemorySigner`] through [`ChannelSigner::provide_channel_parameters`].
295 /// [`InMemorySigner`]: crate::chain::keysinterface::InMemorySigner
296 /// [`ChannelSigner::provide_channel_parameters`]: crate::chain::keysinterface::ChannelSigner::provide_channel_parameters
297 pub channel_parameters: ChannelTransactionParameters,
298 /// The txid of the commitment transaction in which the HTLC output lives.
299 pub commitment_txid: Txid,
300 /// The number of the commitment transaction in which the HTLC output lives.
301 pub per_commitment_number: u64,
302 /// The details of the HTLC as it appears in the commitment transaction.
303 pub htlc: HTLCOutputInCommitment,
304 /// The preimage, if `Some`, to claim the HTLC output with. If `None`, the timeout path must be
306 pub preimage: Option<PaymentPreimage>,
307 /// The counterparty's signature required to spend the HTLC output.
308 pub counterparty_sig: Signature
312 impl HTLCDescriptor {
313 /// Returns the unsigned transaction input spending the HTLC output in the commitment
315 pub fn unsigned_tx_input(&self) -> TxIn {
316 chan_utils::build_htlc_input(&self.commitment_txid, &self.htlc, true /* opt_anchors */)
319 /// Returns the delayed output created as a result of spending the HTLC output in the commitment
321 pub fn tx_output<C: secp256k1::Signing + secp256k1::Verification>(
322 &self, per_commitment_point: &PublicKey, secp: &Secp256k1<C>
324 let channel_params = self.channel_parameters.as_holder_broadcastable();
325 let broadcaster_keys = channel_params.broadcaster_pubkeys();
326 let counterparty_keys = channel_params.countersignatory_pubkeys();
327 let broadcaster_delayed_key = chan_utils::derive_public_key(
328 secp, per_commitment_point, &broadcaster_keys.delayed_payment_basepoint
330 let counterparty_revocation_key = chan_utils::derive_public_revocation_key(
331 secp, per_commitment_point, &counterparty_keys.revocation_basepoint
333 chan_utils::build_htlc_output(
334 0 /* feerate_per_kw */, channel_params.contest_delay(), &self.htlc, true /* opt_anchors */,
335 false /* use_non_zero_fee_anchors */, &broadcaster_delayed_key, &counterparty_revocation_key
339 /// Returns the witness script of the HTLC output in the commitment transaction.
340 pub fn witness_script<C: secp256k1::Signing + secp256k1::Verification>(
341 &self, per_commitment_point: &PublicKey, secp: &Secp256k1<C>
343 let channel_params = self.channel_parameters.as_holder_broadcastable();
344 let broadcaster_keys = channel_params.broadcaster_pubkeys();
345 let counterparty_keys = channel_params.countersignatory_pubkeys();
346 let broadcaster_htlc_key = chan_utils::derive_public_key(
347 secp, per_commitment_point, &broadcaster_keys.htlc_basepoint
349 let counterparty_htlc_key = chan_utils::derive_public_key(
350 secp, per_commitment_point, &counterparty_keys.htlc_basepoint
352 let counterparty_revocation_key = chan_utils::derive_public_revocation_key(
353 secp, per_commitment_point, &counterparty_keys.revocation_basepoint
355 chan_utils::get_htlc_redeemscript_with_explicit_keys(
356 &self.htlc, true /* opt_anchors */, &broadcaster_htlc_key, &counterparty_htlc_key,
357 &counterparty_revocation_key,
361 /// Returns the fully signed witness required to spend the HTLC output in the commitment
363 pub fn tx_input_witness(&self, signature: &Signature, witness_script: &Script) -> Witness {
364 chan_utils::build_htlc_input_witness(
365 signature, &self.counterparty_sig, &self.preimage, witness_script, true /* opt_anchors */
371 /// Represents the different types of transactions, originating from LDK, to be bumped.
372 #[derive(Clone, Debug, PartialEq, Eq)]
373 pub enum BumpTransactionEvent {
374 /// Indicates that a channel featuring anchor outputs is to be closed by broadcasting the local
375 /// commitment transaction. Since commitment transactions have a static feerate pre-agreed upon,
376 /// they may need additional fees to be attached through a child transaction using the popular
377 /// [Child-Pays-For-Parent](https://bitcoinops.org/en/topics/cpfp) fee bumping technique. This
378 /// child transaction must include the anchor input described within `anchor_descriptor` along
379 /// with additional inputs to meet the target feerate. Failure to meet the target feerate
380 /// decreases the confirmation odds of the transaction package (which includes the commitment
381 /// and child anchor transactions), possibly resulting in a loss of funds. Once the transaction
382 /// is constructed, it must be fully signed for and broadcast by the consumer of the event
383 /// along with the `commitment_tx` enclosed. Note that the `commitment_tx` must always be
384 /// broadcast first, as the child anchor transaction depends on it.
386 /// The consumer should be able to sign for any of the additional inputs included within the
387 /// child anchor transaction. To sign its anchor input, an [`InMemorySigner`] should be
388 /// re-derived through [`KeysManager::derive_channel_keys`] with the help of
389 /// [`AnchorDescriptor::channel_keys_id`] and [`AnchorDescriptor::channel_value_satoshis`]. The
390 /// anchor input signature can be computed with [`EcdsaChannelSigner::sign_holder_anchor_input`],
391 /// which can then be provided to [`build_anchor_input_witness`] along with the `funding_pubkey`
392 /// to obtain the full witness required to spend.
394 /// It is possible to receive more than one instance of this event if a valid child anchor
395 /// transaction is never broadcast or is but not with a sufficient fee to be mined. Care should
396 /// be taken by the consumer of the event to ensure any future iterations of the child anchor
397 /// transaction adhere to the [Replace-By-Fee
398 /// rules](https://github.com/bitcoin/bitcoin/blob/master/doc/policy/mempool-replacements.md)
399 /// for fee bumps to be accepted into the mempool, and eventually the chain. As the frequency of
400 /// these events is not user-controlled, users may ignore/drop the event if they are no longer
401 /// able to commit external confirmed funds to the child anchor transaction.
403 /// The set of `pending_htlcs` on the commitment transaction to be broadcast can be inspected to
404 /// determine whether a significant portion of the channel's funds are allocated to HTLCs,
405 /// enabling users to make their own decisions regarding the importance of the commitment
406 /// transaction's confirmation. Note that this is not required, but simply exists as an option
407 /// for users to override LDK's behavior. On commitments with no HTLCs (indicated by those with
408 /// an empty `pending_htlcs`), confirmation of the commitment transaction can be considered to
411 /// [`InMemorySigner`]: crate::chain::keysinterface::InMemorySigner
412 /// [`KeysManager::derive_channel_keys`]: crate::chain::keysinterface::KeysManager::derive_channel_keys
413 /// [`EcdsaChannelSigner::sign_holder_anchor_input`]: crate::chain::keysinterface::EcdsaChannelSigner::sign_holder_anchor_input
414 /// [`build_anchor_input_witness`]: crate::ln::chan_utils::build_anchor_input_witness
416 /// The target feerate that the transaction package, which consists of the commitment
417 /// transaction and the to-be-crafted child anchor transaction, must meet.
418 package_target_feerate_sat_per_1000_weight: u32,
419 /// The channel's commitment transaction to bump the fee of. This transaction should be
420 /// broadcast along with the anchor transaction constructed as a result of consuming this
422 commitment_tx: Transaction,
423 /// The absolute fee in satoshis of the commitment transaction. This can be used along the
424 /// with weight of the commitment transaction to determine its feerate.
425 commitment_tx_fee_satoshis: u64,
426 /// The descriptor to sign the anchor input of the anchor transaction constructed as a
427 /// result of consuming this event.
428 anchor_descriptor: AnchorDescriptor,
429 /// The set of pending HTLCs on the commitment transaction that need to be resolved once the
430 /// commitment transaction confirms.
431 pending_htlcs: Vec<HTLCOutputInCommitment>,
433 /// Indicates that a channel featuring anchor outputs has unilaterally closed on-chain by a
434 /// holder commitment transaction and its HTLC(s) need to be resolved on-chain. With the
435 /// zero-HTLC-transaction-fee variant of anchor outputs, the pre-signed HTLC
436 /// transactions have a zero fee, thus requiring additional inputs and/or outputs to be attached
437 /// for a timely confirmation within the chain. These additional inputs and/or outputs must be
438 /// appended to the resulting HTLC transaction to meet the target feerate. Failure to meet the
439 /// target feerate decreases the confirmation odds of the transaction, possibly resulting in a
440 /// loss of funds. Once the transaction meets the target feerate, it must be signed for and
441 /// broadcast by the consumer of the event.
443 /// The consumer should be able to sign for any of the non-HTLC inputs added to the resulting
444 /// HTLC transaction. To sign HTLC inputs, an [`InMemorySigner`] should be re-derived through
445 /// [`KeysManager::derive_channel_keys`] with the help of `channel_keys_id` and
446 /// `channel_value_satoshis`. Each HTLC input's signature can be computed with
447 /// [`EcdsaChannelSigner::sign_holder_htlc_transaction`], which can then be provided to
448 /// [`HTLCDescriptor::tx_input_witness`] to obtain the fully signed witness required to spend.
450 /// It is possible to receive more than one instance of this event if a valid HTLC transaction
451 /// is never broadcast or is but not with a sufficient fee to be mined. Care should be taken by
452 /// the consumer of the event to ensure any future iterations of the HTLC transaction adhere to
453 /// the [Replace-By-Fee
454 /// rules](https://github.com/bitcoin/bitcoin/blob/master/doc/policy/mempool-replacements.md)
455 /// for fee bumps to be accepted into the mempool, and eventually the chain. As the frequency of
456 /// these events is not user-controlled, users may ignore/drop the event if either they are no
457 /// longer able to commit external confirmed funds to the HTLC transaction or the fee committed
458 /// to the HTLC transaction is greater in value than the HTLCs being claimed.
460 /// [`InMemorySigner`]: crate::chain::keysinterface::InMemorySigner
461 /// [`KeysManager::derive_channel_keys`]: crate::chain::keysinterface::KeysManager::derive_channel_keys
462 /// [`EcdsaChannelSigner::sign_holder_htlc_transaction`]: crate::chain::keysinterface::EcdsaChannelSigner::sign_holder_htlc_transaction
463 /// [`HTLCDescriptor::tx_input_witness`]: HTLCDescriptor::tx_input_witness
465 target_feerate_sat_per_1000_weight: u32,
466 htlc_descriptors: Vec<HTLCDescriptor>,
470 /// Will be used in [`Event::HTLCIntercepted`] to identify the next hop in the HTLC's path.
471 /// Currently only used in serialization for the sake of maintaining compatibility. More variants
472 /// will be added for general-purpose HTLC forward intercepts as well as trampoline forward
473 /// intercepts in upcoming work.
474 enum InterceptNextHop {
476 requested_next_hop_scid: u64,
480 impl_writeable_tlv_based_enum!(InterceptNextHop,
482 (0, requested_next_hop_scid, required),
486 /// An Event which you should probably take some action in response to.
488 /// Note that while Writeable and Readable are implemented for Event, you probably shouldn't use
489 /// them directly as they don't round-trip exactly (for example FundingGenerationReady is never
490 /// written as it makes no sense to respond to it after reconnecting to peers).
491 #[derive(Clone, Debug, PartialEq, Eq)]
493 /// Used to indicate that the client should generate a funding transaction with the given
494 /// parameters and then call [`ChannelManager::funding_transaction_generated`].
495 /// Generated in [`ChannelManager`] message handling.
496 /// Note that *all inputs* in the funding transaction must spend SegWit outputs or your
497 /// counterparty can steal your funds!
499 /// [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
500 /// [`ChannelManager::funding_transaction_generated`]: crate::ln::channelmanager::ChannelManager::funding_transaction_generated
501 FundingGenerationReady {
502 /// The random channel_id we picked which you'll need to pass into
503 /// [`ChannelManager::funding_transaction_generated`].
505 /// [`ChannelManager::funding_transaction_generated`]: crate::ln::channelmanager::ChannelManager::funding_transaction_generated
506 temporary_channel_id: [u8; 32],
507 /// The counterparty's node_id, which you'll need to pass back into
508 /// [`ChannelManager::funding_transaction_generated`].
510 /// [`ChannelManager::funding_transaction_generated`]: crate::ln::channelmanager::ChannelManager::funding_transaction_generated
511 counterparty_node_id: PublicKey,
512 /// The value, in satoshis, that the output should have.
513 channel_value_satoshis: u64,
514 /// The script which should be used in the transaction output.
515 output_script: Script,
516 /// The `user_channel_id` value passed in to [`ChannelManager::create_channel`], or a
517 /// random value for an inbound channel. This may be zero for objects serialized with LDK
518 /// versions prior to 0.0.113.
520 /// [`ChannelManager::create_channel`]: crate::ln::channelmanager::ChannelManager::create_channel
521 user_channel_id: u128,
523 /// Indicates that we've been offered a payment and it needs to be claimed via calling
524 /// [`ChannelManager::claim_funds`] with the preimage given in [`PaymentPurpose`].
526 /// Note that if the preimage is not known, you should call
527 /// [`ChannelManager::fail_htlc_backwards`] or [`ChannelManager::fail_htlc_backwards_with_reason`]
528 /// to free up resources for this HTLC and avoid network congestion.
529 /// If you fail to call either [`ChannelManager::claim_funds`], [`ChannelManager::fail_htlc_backwards`],
530 /// or [`ChannelManager::fail_htlc_backwards_with_reason`] within the HTLC's timeout, the HTLC will be
531 /// automatically failed.
534 /// LDK will not stop an inbound payment from being paid multiple times, so multiple
535 /// `PaymentClaimable` events may be generated for the same payment.
538 /// This event used to be called `PaymentReceived` in LDK versions 0.0.112 and earlier.
540 /// [`ChannelManager::claim_funds`]: crate::ln::channelmanager::ChannelManager::claim_funds
541 /// [`ChannelManager::fail_htlc_backwards`]: crate::ln::channelmanager::ChannelManager::fail_htlc_backwards
542 /// [`ChannelManager::fail_htlc_backwards_with_reason`]: crate::ln::channelmanager::ChannelManager::fail_htlc_backwards_with_reason
544 /// The node that will receive the payment after it has been claimed.
545 /// This is useful to identify payments received via [phantom nodes].
546 /// This field will always be filled in when the event was generated by LDK versions
547 /// 0.0.113 and above.
549 /// [phantom nodes]: crate::chain::keysinterface::PhantomKeysManager
550 receiver_node_id: Option<PublicKey>,
551 /// The hash for which the preimage should be handed to the ChannelManager. Note that LDK will
552 /// not stop you from registering duplicate payment hashes for inbound payments.
553 payment_hash: PaymentHash,
554 /// The value, in thousandths of a satoshi, that this payment is for.
556 /// Information for claiming this received payment, based on whether the purpose of the
557 /// payment is to pay an invoice or to send a spontaneous payment.
558 purpose: PaymentPurpose,
559 /// The `channel_id` indicating over which channel we received the payment.
560 via_channel_id: Option<[u8; 32]>,
561 /// The `user_channel_id` indicating over which channel we received the payment.
562 via_user_channel_id: Option<u128>,
564 /// Indicates a payment has been claimed and we've received money!
566 /// This most likely occurs when [`ChannelManager::claim_funds`] has been called in response
567 /// to an [`Event::PaymentClaimable`]. However, if we previously crashed during a
568 /// [`ChannelManager::claim_funds`] call you may see this event without a corresponding
569 /// [`Event::PaymentClaimable`] event.
572 /// LDK will not stop an inbound payment from being paid multiple times, so multiple
573 /// `PaymentClaimable` events may be generated for the same payment. If you then call
574 /// [`ChannelManager::claim_funds`] twice for the same [`Event::PaymentClaimable`] you may get
575 /// multiple `PaymentClaimed` events.
577 /// [`ChannelManager::claim_funds`]: crate::ln::channelmanager::ChannelManager::claim_funds
579 /// The node that received the payment.
580 /// This is useful to identify payments which were received via [phantom nodes].
581 /// This field will always be filled in when the event was generated by LDK versions
582 /// 0.0.113 and above.
584 /// [phantom nodes]: crate::chain::keysinterface::PhantomKeysManager
585 receiver_node_id: Option<PublicKey>,
586 /// The payment hash of the claimed payment. Note that LDK will not stop you from
587 /// registering duplicate payment hashes for inbound payments.
588 payment_hash: PaymentHash,
589 /// The value, in thousandths of a satoshi, that this payment is for.
591 /// The purpose of the claimed payment, i.e. whether the payment was for an invoice or a
592 /// spontaneous payment.
593 purpose: PaymentPurpose,
595 /// Indicates an outbound payment we made succeeded (i.e. it made it all the way to its target
596 /// and we got back the payment preimage for it).
598 /// Note for MPP payments: in rare cases, this event may be preceded by a `PaymentPathFailed`
599 /// event. In this situation, you SHOULD treat this payment as having succeeded.
601 /// The id returned by [`ChannelManager::send_payment`].
603 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
604 payment_id: Option<PaymentId>,
605 /// The preimage to the hash given to ChannelManager::send_payment.
606 /// Note that this serves as a payment receipt, if you wish to have such a thing, you must
607 /// store it somehow!
608 payment_preimage: PaymentPreimage,
609 /// The hash that was given to [`ChannelManager::send_payment`].
611 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
612 payment_hash: PaymentHash,
613 /// The total fee which was spent at intermediate hops in this payment, across all paths.
615 /// Note that, like [`Route::get_total_fees`] this does *not* include any potential
616 /// overpayment to the recipient node.
618 /// If the recipient or an intermediate node misbehaves and gives us free money, this may
619 /// overstate the amount paid, though this is unlikely.
621 /// [`Route::get_total_fees`]: crate::routing::router::Route::get_total_fees
622 fee_paid_msat: Option<u64>,
624 /// Indicates an outbound payment failed. Individual [`Event::PaymentPathFailed`] events
625 /// provide failure information for each path attempt in the payment, including retries.
627 /// This event is provided once there are no further pending HTLCs for the payment and the
628 /// payment is no longer retryable, due either to the [`Retry`] provided or
629 /// [`ChannelManager::abandon_payment`] having been called for the corresponding payment.
631 /// [`Retry`]: crate::ln::channelmanager::Retry
632 /// [`ChannelManager::abandon_payment`]: crate::ln::channelmanager::ChannelManager::abandon_payment
634 /// The id returned by [`ChannelManager::send_payment`] and used with
635 /// [`ChannelManager::abandon_payment`].
637 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
638 /// [`ChannelManager::abandon_payment`]: crate::ln::channelmanager::ChannelManager::abandon_payment
639 payment_id: PaymentId,
640 /// The hash that was given to [`ChannelManager::send_payment`].
642 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
643 payment_hash: PaymentHash,
645 /// Indicates that a path for an outbound payment was successful.
647 /// Always generated after [`Event::PaymentSent`] and thus useful for scoring channels. See
648 /// [`Event::PaymentSent`] for obtaining the payment preimage.
649 PaymentPathSuccessful {
650 /// The id returned by [`ChannelManager::send_payment`].
652 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
653 payment_id: PaymentId,
654 /// The hash that was given to [`ChannelManager::send_payment`].
656 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
657 payment_hash: Option<PaymentHash>,
658 /// The payment path that was successful.
660 /// May contain a closed channel if the HTLC sent along the path was fulfilled on chain.
663 /// Indicates an outbound HTLC we sent failed, likely due to an intermediary node being unable to
666 /// Note that this does *not* indicate that all paths for an MPP payment have failed, see
667 /// [`Event::PaymentFailed`].
669 /// See [`ChannelManager::abandon_payment`] for giving up on this payment before its retries have
672 /// [`ChannelManager::abandon_payment`]: crate::ln::channelmanager::ChannelManager::abandon_payment
674 /// The id returned by [`ChannelManager::send_payment`] and used with
675 /// [`ChannelManager::abandon_payment`].
677 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
678 /// [`ChannelManager::abandon_payment`]: crate::ln::channelmanager::ChannelManager::abandon_payment
679 payment_id: Option<PaymentId>,
680 /// The hash that was given to [`ChannelManager::send_payment`].
682 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
683 payment_hash: PaymentHash,
684 /// Indicates the payment was rejected for some reason by the recipient. This implies that
685 /// the payment has failed, not just the route in question. If this is not set, the payment may
686 /// be retried via a different route.
687 payment_failed_permanently: bool,
688 /// Extra error details based on the failure type. May contain an update that needs to be
689 /// applied to the [`NetworkGraph`].
691 /// [`NetworkGraph`]: crate::routing::gossip::NetworkGraph
692 failure: PathFailure,
693 /// The payment path that failed.
695 /// The channel responsible for the failed payment path.
697 /// Note that for route hints or for the first hop in a path this may be an SCID alias and
698 /// may not refer to a channel in the public network graph. These aliases may also collide
699 /// with channels in the public network graph.
701 /// If this is `Some`, then the corresponding channel should be avoided when the payment is
702 /// retried. May be `None` for older [`Event`] serializations.
703 short_channel_id: Option<u64>,
705 error_code: Option<u16>,
707 error_data: Option<Vec<u8>>,
709 /// Indicates that a probe payment we sent returned successful, i.e., only failed at the destination.
711 /// The id returned by [`ChannelManager::send_probe`].
713 /// [`ChannelManager::send_probe`]: crate::ln::channelmanager::ChannelManager::send_probe
714 payment_id: PaymentId,
715 /// The hash generated by [`ChannelManager::send_probe`].
717 /// [`ChannelManager::send_probe`]: crate::ln::channelmanager::ChannelManager::send_probe
718 payment_hash: PaymentHash,
719 /// The payment path that was successful.
722 /// Indicates that a probe payment we sent failed at an intermediary node on the path.
724 /// The id returned by [`ChannelManager::send_probe`].
726 /// [`ChannelManager::send_probe`]: crate::ln::channelmanager::ChannelManager::send_probe
727 payment_id: PaymentId,
728 /// The hash generated by [`ChannelManager::send_probe`].
730 /// [`ChannelManager::send_probe`]: crate::ln::channelmanager::ChannelManager::send_probe
731 payment_hash: PaymentHash,
732 /// The payment path that failed.
734 /// The channel responsible for the failed probe.
736 /// Note that for route hints or for the first hop in a path this may be an SCID alias and
737 /// may not refer to a channel in the public network graph. These aliases may also collide
738 /// with channels in the public network graph.
739 short_channel_id: Option<u64>,
741 /// Used to indicate that [`ChannelManager::process_pending_htlc_forwards`] should be called at
742 /// a time in the future.
744 /// [`ChannelManager::process_pending_htlc_forwards`]: crate::ln::channelmanager::ChannelManager::process_pending_htlc_forwards
745 PendingHTLCsForwardable {
746 /// The minimum amount of time that should be waited prior to calling
747 /// process_pending_htlc_forwards. To increase the effort required to correlate payments,
748 /// you should wait a random amount of time in roughly the range (now + time_forwardable,
749 /// now + 5*time_forwardable).
750 time_forwardable: Duration,
752 /// Used to indicate that we've intercepted an HTLC forward. This event will only be generated if
753 /// you've encoded an intercept scid in the receiver's invoice route hints using
754 /// [`ChannelManager::get_intercept_scid`] and have set [`UserConfig::accept_intercept_htlcs`].
756 /// [`ChannelManager::forward_intercepted_htlc`] or
757 /// [`ChannelManager::fail_intercepted_htlc`] MUST be called in response to this event. See
758 /// their docs for more information.
760 /// [`ChannelManager::get_intercept_scid`]: crate::ln::channelmanager::ChannelManager::get_intercept_scid
761 /// [`UserConfig::accept_intercept_htlcs`]: crate::util::config::UserConfig::accept_intercept_htlcs
762 /// [`ChannelManager::forward_intercepted_htlc`]: crate::ln::channelmanager::ChannelManager::forward_intercepted_htlc
763 /// [`ChannelManager::fail_intercepted_htlc`]: crate::ln::channelmanager::ChannelManager::fail_intercepted_htlc
765 /// An id to help LDK identify which HTLC is being forwarded or failed.
766 intercept_id: InterceptId,
767 /// The fake scid that was programmed as the next hop's scid, generated using
768 /// [`ChannelManager::get_intercept_scid`].
770 /// [`ChannelManager::get_intercept_scid`]: crate::ln::channelmanager::ChannelManager::get_intercept_scid
771 requested_next_hop_scid: u64,
772 /// The payment hash used for this HTLC.
773 payment_hash: PaymentHash,
774 /// How many msats were received on the inbound edge of this HTLC.
775 inbound_amount_msat: u64,
776 /// How many msats the payer intended to route to the next node. Depending on the reason you are
777 /// intercepting this payment, you might take a fee by forwarding less than this amount.
779 /// Note that LDK will NOT check that expected fees were factored into this value. You MUST
780 /// check that whatever fee you want has been included here or subtract it as required. Further,
781 /// LDK will not stop you from forwarding more than you received.
782 expected_outbound_amount_msat: u64,
784 /// Used to indicate that an output which you should know how to spend was confirmed on chain
785 /// and is now spendable.
786 /// Such an output will *not* ever be spent by rust-lightning, and are not at risk of your
787 /// counterparty spending them due to some kind of timeout. Thus, you need to store them
788 /// somewhere and spend them when you create on-chain transactions.
790 /// The outputs which you should store as spendable by you.
791 outputs: Vec<SpendableOutputDescriptor>,
793 /// This event is generated when a payment has been successfully forwarded through us and a
794 /// forwarding fee earned.
796 /// The incoming channel between the previous node and us. This is only `None` for events
797 /// generated or serialized by versions prior to 0.0.107.
798 prev_channel_id: Option<[u8; 32]>,
799 /// The outgoing channel between the next node and us. This is only `None` for events
800 /// generated or serialized by versions prior to 0.0.107.
801 next_channel_id: Option<[u8; 32]>,
802 /// The fee, in milli-satoshis, which was earned as a result of the payment.
804 /// Note that if we force-closed the channel over which we forwarded an HTLC while the HTLC
805 /// was pending, the amount the next hop claimed will have been rounded down to the nearest
806 /// whole satoshi. Thus, the fee calculated here may be higher than expected as we still
807 /// claimed the full value in millisatoshis from the source. In this case,
808 /// `claim_from_onchain_tx` will be set.
810 /// If the channel which sent us the payment has been force-closed, we will claim the funds
811 /// via an on-chain transaction. In that case we do not yet know the on-chain transaction
812 /// fees which we will spend and will instead set this to `None`. It is possible duplicate
813 /// `PaymentForwarded` events are generated for the same payment iff `fee_earned_msat` is
815 fee_earned_msat: Option<u64>,
816 /// If this is `true`, the forwarded HTLC was claimed by our counterparty via an on-chain
818 claim_from_onchain_tx: bool,
820 /// Used to indicate that a channel with the given `channel_id` is ready to
821 /// be used. This event is emitted either when the funding transaction has been confirmed
822 /// on-chain, or, in case of a 0conf channel, when both parties have confirmed the channel
825 /// The channel_id of the channel that is ready.
826 channel_id: [u8; 32],
827 /// The `user_channel_id` value passed in to [`ChannelManager::create_channel`] for outbound
828 /// channels, or to [`ChannelManager::accept_inbound_channel`] for inbound channels if
829 /// [`UserConfig::manually_accept_inbound_channels`] config flag is set to true. Otherwise
830 /// `user_channel_id` will be randomized for an inbound channel.
832 /// [`ChannelManager::create_channel`]: crate::ln::channelmanager::ChannelManager::create_channel
833 /// [`ChannelManager::accept_inbound_channel`]: crate::ln::channelmanager::ChannelManager::accept_inbound_channel
834 /// [`UserConfig::manually_accept_inbound_channels`]: crate::util::config::UserConfig::manually_accept_inbound_channels
835 user_channel_id: u128,
836 /// The node_id of the channel counterparty.
837 counterparty_node_id: PublicKey,
838 /// The features that this channel will operate with.
839 channel_type: ChannelTypeFeatures,
841 /// Used to indicate that a previously opened channel with the given `channel_id` is in the
842 /// process of closure.
844 /// The channel_id of the channel which has been closed. Note that on-chain transactions
845 /// resolving the channel are likely still awaiting confirmation.
846 channel_id: [u8; 32],
847 /// The `user_channel_id` value passed in to [`ChannelManager::create_channel`] for outbound
848 /// channels, or to [`ChannelManager::accept_inbound_channel`] for inbound channels if
849 /// [`UserConfig::manually_accept_inbound_channels`] config flag is set to true. Otherwise
850 /// `user_channel_id` will be randomized for inbound channels.
851 /// This may be zero for inbound channels serialized prior to 0.0.113 and will always be
852 /// zero for objects serialized with LDK versions prior to 0.0.102.
854 /// [`ChannelManager::create_channel`]: crate::ln::channelmanager::ChannelManager::create_channel
855 /// [`ChannelManager::accept_inbound_channel`]: crate::ln::channelmanager::ChannelManager::accept_inbound_channel
856 /// [`UserConfig::manually_accept_inbound_channels`]: crate::util::config::UserConfig::manually_accept_inbound_channels
857 user_channel_id: u128,
858 /// The reason the channel was closed.
859 reason: ClosureReason
861 /// Used to indicate to the user that they can abandon the funding transaction and recycle the
862 /// inputs for another purpose.
864 /// The channel_id of the channel which has been closed.
865 channel_id: [u8; 32],
866 /// The full transaction received from the user
867 transaction: Transaction
869 /// Indicates a request to open a new channel by a peer.
871 /// To accept the request, call [`ChannelManager::accept_inbound_channel`]. To reject the
872 /// request, call [`ChannelManager::force_close_without_broadcasting_txn`].
874 /// The event is only triggered when a new open channel request is received and the
875 /// [`UserConfig::manually_accept_inbound_channels`] config flag is set to true.
877 /// [`ChannelManager::accept_inbound_channel`]: crate::ln::channelmanager::ChannelManager::accept_inbound_channel
878 /// [`ChannelManager::force_close_without_broadcasting_txn`]: crate::ln::channelmanager::ChannelManager::force_close_without_broadcasting_txn
879 /// [`UserConfig::manually_accept_inbound_channels`]: crate::util::config::UserConfig::manually_accept_inbound_channels
881 /// The temporary channel ID of the channel requested to be opened.
883 /// When responding to the request, the `temporary_channel_id` should be passed
884 /// back to the ChannelManager through [`ChannelManager::accept_inbound_channel`] to accept,
885 /// or through [`ChannelManager::force_close_without_broadcasting_txn`] to reject.
887 /// [`ChannelManager::accept_inbound_channel`]: crate::ln::channelmanager::ChannelManager::accept_inbound_channel
888 /// [`ChannelManager::force_close_without_broadcasting_txn`]: crate::ln::channelmanager::ChannelManager::force_close_without_broadcasting_txn
889 temporary_channel_id: [u8; 32],
890 /// The node_id of the counterparty requesting to open the channel.
892 /// When responding to the request, the `counterparty_node_id` should be passed
893 /// back to the `ChannelManager` through [`ChannelManager::accept_inbound_channel`] to
894 /// accept the request, or through [`ChannelManager::force_close_without_broadcasting_txn`] to reject the
897 /// [`ChannelManager::accept_inbound_channel`]: crate::ln::channelmanager::ChannelManager::accept_inbound_channel
898 /// [`ChannelManager::force_close_without_broadcasting_txn`]: crate::ln::channelmanager::ChannelManager::force_close_without_broadcasting_txn
899 counterparty_node_id: PublicKey,
900 /// The channel value of the requested channel.
901 funding_satoshis: u64,
902 /// Our starting balance in the channel if the request is accepted, in milli-satoshi.
904 /// The features that this channel will operate with. If you reject the channel, a
905 /// well-behaved counterparty may automatically re-attempt the channel with a new set of
908 /// Note that if [`ChannelTypeFeatures::supports_scid_privacy`] returns true on this type,
909 /// the resulting [`ChannelManager`] will not be readable by versions of LDK prior to
912 /// Furthermore, note that if [`ChannelTypeFeatures::supports_zero_conf`] returns true on this type,
913 /// the resulting [`ChannelManager`] will not be readable by versions of LDK prior to
914 /// 0.0.107. Channels setting this type also need to get manually accepted via
915 /// [`crate::ln::channelmanager::ChannelManager::accept_inbound_channel_from_trusted_peer_0conf`],
916 /// or will be rejected otherwise.
918 /// [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
919 channel_type: ChannelTypeFeatures,
921 /// Indicates that the HTLC was accepted, but could not be processed when or after attempting to
924 /// Some scenarios where this event may be sent include:
925 /// * Insufficient capacity in the outbound channel
926 /// * While waiting to forward the HTLC, the channel it is meant to be forwarded through closes
927 /// * When an unknown SCID is requested for forwarding a payment.
928 /// * Claiming an amount for an MPP payment that exceeds the HTLC total
929 /// * The HTLC has timed out
931 /// This event, however, does not get generated if an HTLC fails to meet the forwarding
932 /// requirements (i.e. insufficient fees paid, or a CLTV that is too soon).
934 /// The channel over which the HTLC was received.
935 prev_channel_id: [u8; 32],
936 /// Destination of the HTLC that failed to be processed.
937 failed_next_destination: HTLCDestination,
940 /// Indicates that a transaction originating from LDK needs to have its fee bumped. This event
941 /// requires confirmed external funds to be readily available to spend.
943 /// LDK does not currently generate this event. It is limited to the scope of channels with
944 /// anchor outputs, which will be introduced in a future release.
945 BumpTransaction(BumpTransactionEvent),
948 impl Writeable for Event {
949 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
951 &Event::FundingGenerationReady { .. } => {
953 // We never write out FundingGenerationReady events as, upon disconnection, peers
954 // drop any channels which have not yet exchanged funding_signed.
956 &Event::PaymentClaimable { ref payment_hash, ref amount_msat, ref purpose, ref receiver_node_id, ref via_channel_id, ref via_user_channel_id } => {
958 let mut payment_secret = None;
959 let payment_preimage;
961 PaymentPurpose::InvoicePayment { payment_preimage: preimage, payment_secret: secret } => {
962 payment_secret = Some(secret);
963 payment_preimage = *preimage;
965 PaymentPurpose::SpontaneousPayment(preimage) => {
966 payment_preimage = Some(*preimage);
969 write_tlv_fields!(writer, {
970 (0, payment_hash, required),
971 (1, receiver_node_id, option),
972 (2, payment_secret, option),
973 (3, via_channel_id, option),
974 (4, amount_msat, required),
975 (5, via_user_channel_id, option),
976 (6, 0u64, required), // user_payment_id required for compatibility with 0.0.103 and earlier
977 (8, payment_preimage, option),
980 &Event::PaymentSent { ref payment_id, ref payment_preimage, ref payment_hash, ref fee_paid_msat } => {
982 write_tlv_fields!(writer, {
983 (0, payment_preimage, required),
984 (1, payment_hash, required),
985 (3, payment_id, option),
986 (5, fee_paid_msat, option),
989 &Event::PaymentPathFailed {
990 ref payment_id, ref payment_hash, ref payment_failed_permanently, ref failure,
991 ref path, ref short_channel_id,
999 error_code.write(writer)?;
1001 error_data.write(writer)?;
1002 write_tlv_fields!(writer, {
1003 (0, payment_hash, required),
1004 (1, None::<NetworkUpdate>, option), // network_update in LDK versions prior to 0.0.114
1005 (2, payment_failed_permanently, required),
1006 (3, false, required), // all_paths_failed in LDK versions prior to 0.0.114
1007 (5, *path, vec_type),
1008 (7, short_channel_id, option),
1009 (9, None::<RouteParameters>, option), // retry in LDK versions prior to 0.0.115
1010 (11, payment_id, option),
1011 (13, failure, required),
1014 &Event::PendingHTLCsForwardable { time_forwardable: _ } => {
1016 // Note that we now ignore these on the read end as we'll re-generate them in
1017 // ChannelManager, we write them here only for backwards compatibility.
1019 &Event::SpendableOutputs { ref outputs } => {
1021 write_tlv_fields!(writer, {
1022 (0, WithoutLength(outputs), required),
1025 &Event::HTLCIntercepted { requested_next_hop_scid, payment_hash, inbound_amount_msat, expected_outbound_amount_msat, intercept_id } => {
1027 let intercept_scid = InterceptNextHop::FakeScid { requested_next_hop_scid };
1028 write_tlv_fields!(writer, {
1029 (0, intercept_id, required),
1030 (2, intercept_scid, required),
1031 (4, payment_hash, required),
1032 (6, inbound_amount_msat, required),
1033 (8, expected_outbound_amount_msat, required),
1036 &Event::PaymentForwarded { fee_earned_msat, prev_channel_id, claim_from_onchain_tx, next_channel_id } => {
1038 write_tlv_fields!(writer, {
1039 (0, fee_earned_msat, option),
1040 (1, prev_channel_id, option),
1041 (2, claim_from_onchain_tx, required),
1042 (3, next_channel_id, option),
1045 &Event::ChannelClosed { ref channel_id, ref user_channel_id, ref reason } => {
1047 // `user_channel_id` used to be a single u64 value. In order to remain backwards
1048 // compatible with versions prior to 0.0.113, the u128 is serialized as two
1049 // separate u64 values.
1050 let user_channel_id_low = *user_channel_id as u64;
1051 let user_channel_id_high = (*user_channel_id >> 64) as u64;
1052 write_tlv_fields!(writer, {
1053 (0, channel_id, required),
1054 (1, user_channel_id_low, required),
1055 (2, reason, required),
1056 (3, user_channel_id_high, required),
1059 &Event::DiscardFunding { ref channel_id, ref transaction } => {
1060 11u8.write(writer)?;
1061 write_tlv_fields!(writer, {
1062 (0, channel_id, required),
1063 (2, transaction, required)
1066 &Event::PaymentPathSuccessful { ref payment_id, ref payment_hash, ref path } => {
1067 13u8.write(writer)?;
1068 write_tlv_fields!(writer, {
1069 (0, payment_id, required),
1070 (2, payment_hash, option),
1071 (4, *path, vec_type)
1074 &Event::PaymentFailed { ref payment_id, ref payment_hash } => {
1075 15u8.write(writer)?;
1076 write_tlv_fields!(writer, {
1077 (0, payment_id, required),
1078 (2, payment_hash, required),
1081 &Event::OpenChannelRequest { .. } => {
1082 17u8.write(writer)?;
1083 // We never write the OpenChannelRequest events as, upon disconnection, peers
1084 // drop any channels which have not yet exchanged funding_signed.
1086 &Event::PaymentClaimed { ref payment_hash, ref amount_msat, ref purpose, ref receiver_node_id } => {
1087 19u8.write(writer)?;
1088 write_tlv_fields!(writer, {
1089 (0, payment_hash, required),
1090 (1, receiver_node_id, option),
1091 (2, purpose, required),
1092 (4, amount_msat, required),
1095 &Event::ProbeSuccessful { ref payment_id, ref payment_hash, ref path } => {
1096 21u8.write(writer)?;
1097 write_tlv_fields!(writer, {
1098 (0, payment_id, required),
1099 (2, payment_hash, required),
1100 (4, *path, vec_type)
1103 &Event::ProbeFailed { ref payment_id, ref payment_hash, ref path, ref short_channel_id } => {
1104 23u8.write(writer)?;
1105 write_tlv_fields!(writer, {
1106 (0, payment_id, required),
1107 (2, payment_hash, required),
1108 (4, *path, vec_type),
1109 (6, short_channel_id, option),
1112 &Event::HTLCHandlingFailed { ref prev_channel_id, ref failed_next_destination } => {
1113 25u8.write(writer)?;
1114 write_tlv_fields!(writer, {
1115 (0, prev_channel_id, required),
1116 (2, failed_next_destination, required),
1120 &Event::BumpTransaction(ref event)=> {
1121 27u8.write(writer)?;
1123 // We never write the ChannelClose|HTLCResolution events as they'll be replayed
1124 // upon restarting anyway if they remain unresolved.
1125 BumpTransactionEvent::ChannelClose { .. } => {}
1126 BumpTransactionEvent::HTLCResolution { .. } => {}
1128 write_tlv_fields!(writer, {}); // Write a length field for forwards compat
1130 &Event::ChannelReady { ref channel_id, ref user_channel_id, ref counterparty_node_id, ref channel_type } => {
1131 29u8.write(writer)?;
1132 write_tlv_fields!(writer, {
1133 (0, channel_id, required),
1134 (2, user_channel_id, required),
1135 (4, counterparty_node_id, required),
1136 (6, channel_type, required),
1139 // Note that, going forward, all new events must only write data inside of
1140 // `write_tlv_fields`. Versions 0.0.101+ will ignore odd-numbered events that write
1141 // data via `write_tlv_fields`.
1146 impl MaybeReadable for Event {
1147 fn read<R: io::Read>(reader: &mut R) -> Result<Option<Self>, msgs::DecodeError> {
1148 match Readable::read(reader)? {
1149 // Note that we do not write a length-prefixed TLV for FundingGenerationReady events,
1150 // unlike all other events, thus we return immediately here.
1154 let mut payment_hash = PaymentHash([0; 32]);
1155 let mut payment_preimage = None;
1156 let mut payment_secret = None;
1157 let mut amount_msat = 0;
1158 let mut receiver_node_id = None;
1159 let mut _user_payment_id = None::<u64>; // For compatibility with 0.0.103 and earlier
1160 let mut via_channel_id = None;
1161 let mut via_user_channel_id = None;
1162 read_tlv_fields!(reader, {
1163 (0, payment_hash, required),
1164 (1, receiver_node_id, option),
1165 (2, payment_secret, option),
1166 (3, via_channel_id, option),
1167 (4, amount_msat, required),
1168 (5, via_user_channel_id, option),
1169 (6, _user_payment_id, option),
1170 (8, payment_preimage, option),
1172 let purpose = match payment_secret {
1173 Some(secret) => PaymentPurpose::InvoicePayment {
1175 payment_secret: secret
1177 None if payment_preimage.is_some() => PaymentPurpose::SpontaneousPayment(payment_preimage.unwrap()),
1178 None => return Err(msgs::DecodeError::InvalidValue),
1180 Ok(Some(Event::PaymentClaimable {
1186 via_user_channel_id,
1193 let mut payment_preimage = PaymentPreimage([0; 32]);
1194 let mut payment_hash = None;
1195 let mut payment_id = None;
1196 let mut fee_paid_msat = None;
1197 read_tlv_fields!(reader, {
1198 (0, payment_preimage, required),
1199 (1, payment_hash, option),
1200 (3, payment_id, option),
1201 (5, fee_paid_msat, option),
1203 if payment_hash.is_none() {
1204 payment_hash = Some(PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()));
1206 Ok(Some(Event::PaymentSent {
1209 payment_hash: payment_hash.unwrap(),
1218 let error_code = Readable::read(reader)?;
1220 let error_data = Readable::read(reader)?;
1221 let mut payment_hash = PaymentHash([0; 32]);
1222 let mut payment_failed_permanently = false;
1223 let mut network_update = None;
1224 let mut path: Option<Vec<RouteHop>> = Some(vec![]);
1225 let mut short_channel_id = None;
1226 let mut payment_id = None;
1227 let mut failure_opt = None;
1228 read_tlv_fields!(reader, {
1229 (0, payment_hash, required),
1230 (1, network_update, upgradable_option),
1231 (2, payment_failed_permanently, required),
1232 (5, path, vec_type),
1233 (7, short_channel_id, option),
1234 (11, payment_id, option),
1235 (13, failure_opt, upgradable_option),
1237 let failure = failure_opt.unwrap_or_else(|| PathFailure::OnPath { network_update });
1238 Ok(Some(Event::PaymentPathFailed {
1241 payment_failed_permanently,
1243 path: path.unwrap(),
1256 let mut outputs = WithoutLength(Vec::new());
1257 read_tlv_fields!(reader, {
1258 (0, outputs, required),
1260 Ok(Some(Event::SpendableOutputs { outputs: outputs.0 }))
1265 let mut payment_hash = PaymentHash([0; 32]);
1266 let mut intercept_id = InterceptId([0; 32]);
1267 let mut requested_next_hop_scid = InterceptNextHop::FakeScid { requested_next_hop_scid: 0 };
1268 let mut inbound_amount_msat = 0;
1269 let mut expected_outbound_amount_msat = 0;
1270 read_tlv_fields!(reader, {
1271 (0, intercept_id, required),
1272 (2, requested_next_hop_scid, required),
1273 (4, payment_hash, required),
1274 (6, inbound_amount_msat, required),
1275 (8, expected_outbound_amount_msat, required),
1277 let next_scid = match requested_next_hop_scid {
1278 InterceptNextHop::FakeScid { requested_next_hop_scid: scid } => scid
1280 Ok(Some(Event::HTLCIntercepted {
1282 requested_next_hop_scid: next_scid,
1283 inbound_amount_msat,
1284 expected_outbound_amount_msat,
1290 let mut fee_earned_msat = None;
1291 let mut prev_channel_id = None;
1292 let mut claim_from_onchain_tx = false;
1293 let mut next_channel_id = None;
1294 read_tlv_fields!(reader, {
1295 (0, fee_earned_msat, option),
1296 (1, prev_channel_id, option),
1297 (2, claim_from_onchain_tx, required),
1298 (3, next_channel_id, option),
1300 Ok(Some(Event::PaymentForwarded { fee_earned_msat, prev_channel_id, claim_from_onchain_tx, next_channel_id }))
1306 let mut channel_id = [0; 32];
1307 let mut reason = UpgradableRequired(None);
1308 let mut user_channel_id_low_opt: Option<u64> = None;
1309 let mut user_channel_id_high_opt: Option<u64> = None;
1310 read_tlv_fields!(reader, {
1311 (0, channel_id, required),
1312 (1, user_channel_id_low_opt, option),
1313 (2, reason, upgradable_required),
1314 (3, user_channel_id_high_opt, option),
1317 // `user_channel_id` used to be a single u64 value. In order to remain
1318 // backwards compatible with versions prior to 0.0.113, the u128 is serialized
1319 // as two separate u64 values.
1320 let user_channel_id = (user_channel_id_low_opt.unwrap_or(0) as u128) +
1321 ((user_channel_id_high_opt.unwrap_or(0) as u128) << 64);
1323 Ok(Some(Event::ChannelClosed { channel_id, user_channel_id, reason: _init_tlv_based_struct_field!(reason, upgradable_required) }))
1329 let mut channel_id = [0; 32];
1330 let mut transaction = Transaction{ version: 2, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() };
1331 read_tlv_fields!(reader, {
1332 (0, channel_id, required),
1333 (2, transaction, required),
1335 Ok(Some(Event::DiscardFunding { channel_id, transaction } ))
1341 let mut payment_id = PaymentId([0; 32]);
1342 let mut payment_hash = None;
1343 let mut path: Option<Vec<RouteHop>> = Some(vec![]);
1344 read_tlv_fields!(reader, {
1345 (0, payment_id, required),
1346 (2, payment_hash, option),
1347 (4, path, vec_type),
1349 Ok(Some(Event::PaymentPathSuccessful {
1352 path: path.unwrap(),
1359 let mut payment_hash = PaymentHash([0; 32]);
1360 let mut payment_id = PaymentId([0; 32]);
1361 read_tlv_fields!(reader, {
1362 (0, payment_id, required),
1363 (2, payment_hash, required),
1365 Ok(Some(Event::PaymentFailed {
1373 // Value 17 is used for `Event::OpenChannelRequest`.
1378 let mut payment_hash = PaymentHash([0; 32]);
1379 let mut purpose = UpgradableRequired(None);
1380 let mut amount_msat = 0;
1381 let mut receiver_node_id = None;
1382 read_tlv_fields!(reader, {
1383 (0, payment_hash, required),
1384 (1, receiver_node_id, option),
1385 (2, purpose, upgradable_required),
1386 (4, amount_msat, required),
1388 Ok(Some(Event::PaymentClaimed {
1391 purpose: _init_tlv_based_struct_field!(purpose, upgradable_required),
1399 let mut payment_id = PaymentId([0; 32]);
1400 let mut payment_hash = PaymentHash([0; 32]);
1401 let mut path: Option<Vec<RouteHop>> = Some(vec![]);
1402 read_tlv_fields!(reader, {
1403 (0, payment_id, required),
1404 (2, payment_hash, required),
1405 (4, path, vec_type),
1407 Ok(Some(Event::ProbeSuccessful {
1410 path: path.unwrap(),
1417 let mut payment_id = PaymentId([0; 32]);
1418 let mut payment_hash = PaymentHash([0; 32]);
1419 let mut path: Option<Vec<RouteHop>> = Some(vec![]);
1420 let mut short_channel_id = None;
1421 read_tlv_fields!(reader, {
1422 (0, payment_id, required),
1423 (2, payment_hash, required),
1424 (4, path, vec_type),
1425 (6, short_channel_id, option),
1427 Ok(Some(Event::ProbeFailed {
1430 path: path.unwrap(),
1438 let mut prev_channel_id = [0; 32];
1439 let mut failed_next_destination_opt = UpgradableRequired(None);
1440 read_tlv_fields!(reader, {
1441 (0, prev_channel_id, required),
1442 (2, failed_next_destination_opt, upgradable_required),
1444 Ok(Some(Event::HTLCHandlingFailed {
1446 failed_next_destination: _init_tlv_based_struct_field!(failed_next_destination_opt, upgradable_required),
1454 let mut channel_id = [0; 32];
1455 let mut user_channel_id: u128 = 0;
1456 let mut counterparty_node_id = RequiredWrapper(None);
1457 let mut channel_type = RequiredWrapper(None);
1458 read_tlv_fields!(reader, {
1459 (0, channel_id, required),
1460 (2, user_channel_id, required),
1461 (4, counterparty_node_id, required),
1462 (6, channel_type, required),
1465 Ok(Some(Event::ChannelReady {
1468 counterparty_node_id: counterparty_node_id.0.unwrap(),
1469 channel_type: channel_type.0.unwrap()
1474 // Versions prior to 0.0.100 did not ignore odd types, instead returning InvalidValue.
1475 // Version 0.0.100 failed to properly ignore odd types, possibly resulting in corrupt
1477 x if x % 2 == 1 => {
1478 // If the event is of unknown type, assume it was written with `write_tlv_fields`,
1479 // which prefixes the whole thing with a length BigSize. Because the event is
1480 // odd-type unknown, we should treat it as `Ok(None)` even if it has some TLV
1481 // fields that are even. Thus, we avoid using `read_tlv_fields` and simply read
1482 // exactly the number of bytes specified, ignoring them entirely.
1483 let tlv_len: BigSize = Readable::read(reader)?;
1484 FixedLengthReader::new(reader, tlv_len.0)
1485 .eat_remaining().map_err(|_| msgs::DecodeError::ShortRead)?;
1488 _ => Err(msgs::DecodeError::InvalidValue)
1493 /// An event generated by ChannelManager which indicates a message should be sent to a peer (or
1494 /// broadcast to most peers).
1495 /// These events are handled by PeerManager::process_events if you are using a PeerManager.
1496 #[derive(Clone, Debug)]
1497 pub enum MessageSendEvent {
1498 /// Used to indicate that we've accepted a channel open and should send the accept_channel
1499 /// message provided to the given peer.
1501 /// The node_id of the node which should receive this message
1503 /// The message which should be sent.
1504 msg: msgs::AcceptChannel,
1506 /// Used to indicate that we've initiated a channel open and should send the open_channel
1507 /// message provided to the given peer.
1509 /// The node_id of the node which should receive this message
1511 /// The message which should be sent.
1512 msg: msgs::OpenChannel,
1514 /// Used to indicate that a funding_created message should be sent to the peer with the given node_id.
1515 SendFundingCreated {
1516 /// The node_id of the node which should receive this message
1518 /// The message which should be sent.
1519 msg: msgs::FundingCreated,
1521 /// Used to indicate that a funding_signed message should be sent to the peer with the given node_id.
1523 /// The node_id of the node which should receive this message
1525 /// The message which should be sent.
1526 msg: msgs::FundingSigned,
1528 /// Used to indicate that a channel_ready message should be sent to the peer with the given node_id.
1530 /// The node_id of the node which should receive these message(s)
1532 /// The channel_ready message which should be sent.
1533 msg: msgs::ChannelReady,
1535 /// Used to indicate that an announcement_signatures message should be sent to the peer with the given node_id.
1536 SendAnnouncementSignatures {
1537 /// The node_id of the node which should receive these message(s)
1539 /// The announcement_signatures message which should be sent.
1540 msg: msgs::AnnouncementSignatures,
1542 /// Used to indicate that a series of HTLC update messages, as well as a commitment_signed
1543 /// message should be sent to the peer with the given node_id.
1545 /// The node_id of the node which should receive these message(s)
1547 /// The update messages which should be sent. ALL messages in the struct should be sent!
1548 updates: msgs::CommitmentUpdate,
1550 /// Used to indicate that a revoke_and_ack message should be sent to the peer with the given node_id.
1552 /// The node_id of the node which should receive this message
1554 /// The message which should be sent.
1555 msg: msgs::RevokeAndACK,
1557 /// Used to indicate that a closing_signed message should be sent to the peer with the given node_id.
1559 /// The node_id of the node which should receive this message
1561 /// The message which should be sent.
1562 msg: msgs::ClosingSigned,
1564 /// Used to indicate that a shutdown message should be sent to the peer with the given node_id.
1566 /// The node_id of the node which should receive this message
1568 /// The message which should be sent.
1569 msg: msgs::Shutdown,
1571 /// Used to indicate that a channel_reestablish message should be sent to the peer with the given node_id.
1572 SendChannelReestablish {
1573 /// The node_id of the node which should receive this message
1575 /// The message which should be sent.
1576 msg: msgs::ChannelReestablish,
1578 /// Used to send a channel_announcement and channel_update to a specific peer, likely on
1579 /// initial connection to ensure our peers know about our channels.
1580 SendChannelAnnouncement {
1581 /// The node_id of the node which should receive this message
1583 /// The channel_announcement which should be sent.
1584 msg: msgs::ChannelAnnouncement,
1585 /// The followup channel_update which should be sent.
1586 update_msg: msgs::ChannelUpdate,
1588 /// Used to indicate that a channel_announcement and channel_update should be broadcast to all
1589 /// peers (except the peer with node_id either msg.contents.node_id_1 or msg.contents.node_id_2).
1591 /// Note that after doing so, you very likely (unless you did so very recently) want to
1592 /// broadcast a node_announcement (e.g. via [`PeerManager::broadcast_node_announcement`]). This
1593 /// ensures that any nodes which see our channel_announcement also have a relevant
1594 /// node_announcement, including relevant feature flags which may be important for routing
1595 /// through or to us.
1597 /// [`PeerManager::broadcast_node_announcement`]: crate::ln::peer_handler::PeerManager::broadcast_node_announcement
1598 BroadcastChannelAnnouncement {
1599 /// The channel_announcement which should be sent.
1600 msg: msgs::ChannelAnnouncement,
1601 /// The followup channel_update which should be sent.
1602 update_msg: Option<msgs::ChannelUpdate>,
1604 /// Used to indicate that a channel_update should be broadcast to all peers.
1605 BroadcastChannelUpdate {
1606 /// The channel_update which should be sent.
1607 msg: msgs::ChannelUpdate,
1609 /// Used to indicate that a node_announcement should be broadcast to all peers.
1610 BroadcastNodeAnnouncement {
1611 /// The node_announcement which should be sent.
1612 msg: msgs::NodeAnnouncement,
1614 /// Used to indicate that a channel_update should be sent to a single peer.
1615 /// In contrast to [`Self::BroadcastChannelUpdate`], this is used when the channel is a
1616 /// private channel and we shouldn't be informing all of our peers of channel parameters.
1618 /// The node_id of the node which should receive this message
1620 /// The channel_update which should be sent.
1621 msg: msgs::ChannelUpdate,
1623 /// Broadcast an error downstream to be handled
1625 /// The node_id of the node which should receive this message
1627 /// The action which should be taken.
1628 action: msgs::ErrorAction
1630 /// Query a peer for channels with funding transaction UTXOs in a block range.
1631 SendChannelRangeQuery {
1632 /// The node_id of this message recipient
1634 /// The query_channel_range which should be sent.
1635 msg: msgs::QueryChannelRange,
1637 /// Request routing gossip messages from a peer for a list of channels identified by
1638 /// their short_channel_ids.
1640 /// The node_id of this message recipient
1642 /// The query_short_channel_ids which should be sent.
1643 msg: msgs::QueryShortChannelIds,
1645 /// Sends a reply to a channel range query. This may be one of several SendReplyChannelRange events
1646 /// emitted during processing of the query.
1647 SendReplyChannelRange {
1648 /// The node_id of this message recipient
1650 /// The reply_channel_range which should be sent.
1651 msg: msgs::ReplyChannelRange,
1653 /// Sends a timestamp filter for inbound gossip. This should be sent on each new connection to
1654 /// enable receiving gossip messages from the peer.
1655 SendGossipTimestampFilter {
1656 /// The node_id of this message recipient
1658 /// The gossip_timestamp_filter which should be sent.
1659 msg: msgs::GossipTimestampFilter,
1663 /// A trait indicating an object may generate message send events
1664 pub trait MessageSendEventsProvider {
1665 /// Gets the list of pending events which were generated by previous actions, clearing the list
1667 fn get_and_clear_pending_msg_events(&self) -> Vec<MessageSendEvent>;
1670 /// A trait indicating an object may generate onion messages to send
1671 pub trait OnionMessageProvider {
1672 /// Gets the next pending onion message for the peer with the given node id.
1673 fn next_onion_message_for_peer(&self, peer_node_id: PublicKey) -> Option<msgs::OnionMessage>;
1676 /// A trait indicating an object may generate events.
1678 /// Events are processed by passing an [`EventHandler`] to [`process_pending_events`].
1680 /// Implementations of this trait may also feature an async version of event handling, as shown with
1681 /// [`ChannelManager::process_pending_events_async`] and
1682 /// [`ChainMonitor::process_pending_events_async`].
1686 /// When using this trait, [`process_pending_events`] will call [`handle_event`] for each pending
1687 /// event since the last invocation.
1689 /// In order to ensure no [`Event`]s are lost, implementors of this trait will persist [`Event`]s
1690 /// and replay any unhandled events on startup. An [`Event`] is considered handled when
1691 /// [`process_pending_events`] returns, thus handlers MUST fully handle [`Event`]s and persist any
1692 /// relevant changes to disk *before* returning.
1694 /// Further, because an application may crash between an [`Event`] being handled and the
1695 /// implementor of this trait being re-serialized, [`Event`] handling must be idempotent - in
1696 /// effect, [`Event`]s may be replayed.
1698 /// Note, handlers may call back into the provider and thus deadlocking must be avoided. Be sure to
1699 /// consult the provider's documentation on the implication of processing events and how a handler
1700 /// may safely use the provider (e.g., see [`ChannelManager::process_pending_events`] and
1701 /// [`ChainMonitor::process_pending_events`]).
1703 /// (C-not implementable) As there is likely no reason for a user to implement this trait on their
1706 /// [`process_pending_events`]: Self::process_pending_events
1707 /// [`handle_event`]: EventHandler::handle_event
1708 /// [`ChannelManager::process_pending_events`]: crate::ln::channelmanager::ChannelManager#method.process_pending_events
1709 /// [`ChainMonitor::process_pending_events`]: crate::chain::chainmonitor::ChainMonitor#method.process_pending_events
1710 /// [`ChannelManager::process_pending_events_async`]: crate::ln::channelmanager::ChannelManager::process_pending_events_async
1711 /// [`ChainMonitor::process_pending_events_async`]: crate::chain::chainmonitor::ChainMonitor::process_pending_events_async
1712 pub trait EventsProvider {
1713 /// Processes any events generated since the last call using the given event handler.
1715 /// See the trait-level documentation for requirements.
1716 fn process_pending_events<H: Deref>(&self, handler: H) where H::Target: EventHandler;
1719 /// A trait implemented for objects handling events from [`EventsProvider`].
1721 /// An async variation also exists for implementations of [`EventsProvider`] that support async
1722 /// event handling. The async event handler should satisfy the generic bounds: `F:
1723 /// core::future::Future, H: Fn(Event) -> F`.
1724 pub trait EventHandler {
1725 /// Handles the given [`Event`].
1727 /// See [`EventsProvider`] for details that must be considered when implementing this method.
1728 fn handle_event(&self, event: Event);
1731 impl<F> EventHandler for F where F: Fn(Event) {
1732 fn handle_event(&self, event: Event) {
1737 impl<T: EventHandler> EventHandler for Arc<T> {
1738 fn handle_event(&self, event: Event) {
1739 self.deref().handle_event(event)