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;
21 use ln::msgs::DecodeError;
22 use ln::{PaymentPreimage, PaymentHash, PaymentSecret};
23 use routing::network_graph::NetworkUpdate;
24 use util::ser::{BigSize, FixedLengthReader, Writeable, Writer, MaybeReadable, Readable, VecReadWrapper, VecWriteWrapper};
25 use routing::router::{RouteHop, RouteParameters};
27 use bitcoin::Transaction;
28 use bitcoin::blockdata::script::Script;
29 use bitcoin::hashes::Hash;
30 use bitcoin::hashes::sha256::Hash as Sha256;
31 use bitcoin::secp256k1::key::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 #[derive(Clone, Debug, PartialEq)]
70 /// The reason the channel was closed. See individual variants more details.
71 pub enum ClosureReason {
72 /// Closure generated from receiving a peer error message.
74 /// Our counterparty may have broadcasted their latest commitment state, and we have
76 CounterpartyForceClosed {
77 /// The error which the peer sent us.
79 /// The string should be sanitized before it is used (e.g emitted to logs
80 /// or printed to stdout). Otherwise, a well crafted error message may exploit
81 /// a security vulnerability in the terminal emulator or the logging subsystem.
84 /// Closure generated from [`ChannelManager::force_close_channel`], called by the user.
86 /// [`ChannelManager::force_close_channel`]: crate::ln::channelmanager::ChannelManager::force_close_channel.
88 /// The channel was closed after negotiating a cooperative close and we've now broadcasted
89 /// the cooperative close transaction. Note the shutdown may have been initiated by us.
90 //TODO: split between CounterpartyInitiated/LocallyInitiated
92 /// A commitment transaction was confirmed on chain, closing the channel. Most likely this
93 /// commitment transaction came from our counterparty, but it may also have come from
94 /// a copy of our own `ChannelMonitor`.
95 CommitmentTxConfirmed,
96 /// The funding transaction failed to confirm in a timely manner on an inbound channel.
98 /// Closure generated from processing an event, likely a HTLC forward/relay/reception.
100 /// A developer-readable error message which we generated.
103 /// The `PeerManager` informed us that we've disconnected from the peer. We close channels
104 /// if the `PeerManager` informed us that it is unlikely we'll be able to connect to the
105 /// peer again in the future or if the peer disconnected before we finished negotiating
106 /// the channel open. The first case may be caused by incompatible features which our
107 /// counterparty, or we, require.
108 //TODO: split between PeerUnconnectable/PeerDisconnected ?
110 /// Closure generated from `ChannelManager::read` if the ChannelMonitor is newer than
111 /// the ChannelManager deserialized.
112 OutdatedChannelManager
115 impl core::fmt::Display for ClosureReason {
116 fn fmt(&self, f: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {
117 f.write_str("Channel closed because ")?;
119 ClosureReason::CounterpartyForceClosed { peer_msg } => {
120 f.write_str("counterparty force-closed with message ")?;
121 f.write_str(&peer_msg)
123 ClosureReason::HolderForceClosed => f.write_str("user manually force-closed the channel"),
124 ClosureReason::CooperativeClosure => f.write_str("the channel was cooperatively closed"),
125 ClosureReason::CommitmentTxConfirmed => f.write_str("commitment or closing transaction was confirmed on chain."),
126 ClosureReason::FundingTimedOut => write!(f, "funding transaction failed to confirm within {} blocks", FUNDING_CONF_DEADLINE_BLOCKS),
127 ClosureReason::ProcessingError { err } => {
128 f.write_str("of an exception: ")?;
131 ClosureReason::DisconnectedPeer => f.write_str("the peer disconnected prior to the channel being funded"),
132 ClosureReason::OutdatedChannelManager => f.write_str("the ChannelManager read from disk was stale compared to ChannelMonitor(s)"),
137 impl_writeable_tlv_based_enum_upgradable!(ClosureReason,
138 (0, CounterpartyForceClosed) => { (1, peer_msg, required) },
139 (1, FundingTimedOut) => {},
140 (2, HolderForceClosed) => {},
141 (6, CommitmentTxConfirmed) => {},
142 (4, CooperativeClosure) => {},
143 (8, ProcessingError) => { (1, err, required) },
144 (10, DisconnectedPeer) => {},
145 (12, OutdatedChannelManager) => {},
148 /// An Event which you should probably take some action in response to.
150 /// Note that while Writeable and Readable are implemented for Event, you probably shouldn't use
151 /// them directly as they don't round-trip exactly (for example FundingGenerationReady is never
152 /// written as it makes no sense to respond to it after reconnecting to peers).
153 #[derive(Clone, Debug)]
155 /// Used to indicate that the client should generate a funding transaction with the given
156 /// parameters and then call [`ChannelManager::funding_transaction_generated`].
157 /// Generated in [`ChannelManager`] message handling.
158 /// Note that *all inputs* in the funding transaction must spend SegWit outputs or your
159 /// counterparty can steal your funds!
161 /// [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
162 /// [`ChannelManager::funding_transaction_generated`]: crate::ln::channelmanager::ChannelManager::funding_transaction_generated
163 FundingGenerationReady {
164 /// The random channel_id we picked which you'll need to pass into
165 /// ChannelManager::funding_transaction_generated.
166 temporary_channel_id: [u8; 32],
167 /// The value, in satoshis, that the output should have.
168 channel_value_satoshis: u64,
169 /// The script which should be used in the transaction output.
170 output_script: Script,
171 /// The `user_channel_id` value passed in to [`ChannelManager::create_channel`], or 0 for
172 /// an inbound channel.
174 /// [`ChannelManager::create_channel`]: crate::ln::channelmanager::ChannelManager::create_channel
175 user_channel_id: u64,
177 /// Indicates we've received money! Just gotta dig out that payment preimage and feed it to
178 /// [`ChannelManager::claim_funds`] to get it....
179 /// Note that if the preimage is not known, you should call
180 /// [`ChannelManager::fail_htlc_backwards`] to free up resources for this HTLC and avoid
181 /// network congestion.
182 /// If you fail to call either [`ChannelManager::claim_funds`] or
183 /// [`ChannelManager::fail_htlc_backwards`] within the HTLC's timeout, the HTLC will be
184 /// automatically failed.
186 /// [`ChannelManager::claim_funds`]: crate::ln::channelmanager::ChannelManager::claim_funds
187 /// [`ChannelManager::fail_htlc_backwards`]: crate::ln::channelmanager::ChannelManager::fail_htlc_backwards
189 /// The hash for which the preimage should be handed to the ChannelManager.
190 payment_hash: PaymentHash,
191 /// The value, in thousandths of a satoshi, that this payment is for.
193 /// Information for claiming this received payment, based on whether the purpose of the
194 /// payment is to pay an invoice or to send a spontaneous payment.
195 purpose: PaymentPurpose,
197 /// Indicates an outbound payment we made succeeded (i.e. it made it all the way to its target
198 /// and we got back the payment preimage for it).
200 /// Note for MPP payments: in rare cases, this event may be preceded by a `PaymentPathFailed`
201 /// event. In this situation, you SHOULD treat this payment as having succeeded.
203 /// The id returned by [`ChannelManager::send_payment`] and used with
204 /// [`ChannelManager::retry_payment`].
206 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
207 /// [`ChannelManager::retry_payment`]: crate::ln::channelmanager::ChannelManager::retry_payment
208 payment_id: Option<PaymentId>,
209 /// The preimage to the hash given to ChannelManager::send_payment.
210 /// Note that this serves as a payment receipt, if you wish to have such a thing, you must
211 /// store it somehow!
212 payment_preimage: PaymentPreimage,
213 /// The hash that was given to [`ChannelManager::send_payment`].
215 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
216 payment_hash: PaymentHash,
217 /// The total fee which was spent at intermediate hops in this payment, across all paths.
219 /// Note that, like [`Route::get_total_fees`] this does *not* include any potential
220 /// overpayment to the recipient node.
222 /// If the recipient or an intermediate node misbehaves and gives us free money, this may
223 /// overstate the amount paid, though this is unlikely.
225 /// [`Route::get_total_fees`]: crate::routing::router::Route::get_total_fees
226 fee_paid_msat: Option<u64>,
228 /// Indicates an outbound payment we made failed. Probably some intermediary node dropped
229 /// something. You may wish to retry with a different route.
231 /// The id returned by [`ChannelManager::send_payment`] and used with
232 /// [`ChannelManager::retry_payment`].
234 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
235 /// [`ChannelManager::retry_payment`]: crate::ln::channelmanager::ChannelManager::retry_payment
236 payment_id: Option<PaymentId>,
237 /// The hash that was given to [`ChannelManager::send_payment`].
239 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
240 payment_hash: PaymentHash,
241 /// Indicates the payment was rejected for some reason by the recipient. This implies that
242 /// the payment has failed, not just the route in question. If this is not set, you may
243 /// retry the payment via a different route.
244 rejected_by_dest: bool,
245 /// Any failure information conveyed via the Onion return packet by a node along the failed
248 /// Should be applied to the [`NetworkGraph`] so that routing decisions can take into
249 /// account the update. [`NetGraphMsgHandler`] is capable of doing this.
251 /// [`NetworkGraph`]: crate::routing::network_graph::NetworkGraph
252 /// [`NetGraphMsgHandler`]: crate::routing::network_graph::NetGraphMsgHandler
253 network_update: Option<NetworkUpdate>,
254 /// For both single-path and multi-path payments, this is set if all paths of the payment have
255 /// failed. This will be set to false if (1) this is an MPP payment and (2) other parts of the
256 /// larger MPP payment were still in flight when this event was generated.
257 all_paths_failed: bool,
258 /// The payment path that failed.
260 /// The channel responsible for the failed payment path.
262 /// If this is `Some`, then the corresponding channel should be avoided when the payment is
263 /// retried. May be `None` for older [`Event`] serializations.
264 short_channel_id: Option<u64>,
265 /// Parameters needed to compute a new [`Route`] when retrying the failed payment path.
267 /// See [`find_route`] for details.
269 /// [`Route`]: crate::routing::router::Route
270 /// [`find_route`]: crate::routing::router::find_route
271 retry: Option<RouteParameters>,
273 error_code: Option<u16>,
275 error_data: Option<Vec<u8>>,
277 /// Used to indicate that [`ChannelManager::process_pending_htlc_forwards`] should be called at
278 /// a time in the future.
280 /// [`ChannelManager::process_pending_htlc_forwards`]: crate::ln::channelmanager::ChannelManager::process_pending_htlc_forwards
281 PendingHTLCsForwardable {
282 /// The minimum amount of time that should be waited prior to calling
283 /// process_pending_htlc_forwards. To increase the effort required to correlate payments,
284 /// you should wait a random amount of time in roughly the range (now + time_forwardable,
285 /// now + 5*time_forwardable).
286 time_forwardable: Duration,
288 /// Used to indicate that an output which you should know how to spend was confirmed on chain
289 /// and is now spendable.
290 /// Such an output will *not* ever be spent by rust-lightning, and are not at risk of your
291 /// counterparty spending them due to some kind of timeout. Thus, you need to store them
292 /// somewhere and spend them when you create on-chain transactions.
294 /// The outputs which you should store as spendable by you.
295 outputs: Vec<SpendableOutputDescriptor>,
297 /// This event is generated when a payment has been successfully forwarded through us and a
298 /// forwarding fee earned.
300 /// The fee, in milli-satoshis, which was earned as a result of the payment.
302 /// Note that if we force-closed the channel over which we forwarded an HTLC while the HTLC
303 /// was pending, the amount the next hop claimed will have been rounded down to the nearest
304 /// whole satoshi. Thus, the fee calculated here may be higher than expected as we still
305 /// claimed the full value in millisatoshis from the source. In this case,
306 /// `claim_from_onchain_tx` will be set.
308 /// If the channel which sent us the payment has been force-closed, we will claim the funds
309 /// via an on-chain transaction. In that case we do not yet know the on-chain transaction
310 /// fees which we will spend and will instead set this to `None`. It is possible duplicate
311 /// `PaymentForwarded` events are generated for the same payment iff `fee_earned_msat` is
313 fee_earned_msat: Option<u64>,
314 /// If this is `true`, the forwarded HTLC was claimed by our counterparty via an on-chain
316 claim_from_onchain_tx: bool,
318 /// Used to indicate that a channel with the given `channel_id` is in the process of closure.
320 /// The channel_id of the channel which has been closed. Note that on-chain transactions
321 /// resolving the channel are likely still awaiting confirmation.
322 channel_id: [u8; 32],
323 /// The `user_channel_id` value passed in to [`ChannelManager::create_channel`], or 0 for
324 /// an inbound channel. This will always be zero for objects serialized with LDK versions
325 /// prior to 0.0.102.
327 /// [`ChannelManager::create_channel`]: crate::ln::channelmanager::ChannelManager::create_channel
328 user_channel_id: u64,
329 /// The reason the channel was closed.
330 reason: ClosureReason
332 /// Used to indicate to the user that they can abandon the funding transaction and recycle the
333 /// inputs for another purpose.
335 /// The channel_id of the channel which has been closed.
336 channel_id: [u8; 32],
337 /// The full transaction received from the user
338 transaction: Transaction
340 /// Indicates that a path for an outbound payment was successful.
342 /// Always generated after [`Event::PaymentSent`] and thus useful for scoring channels. See
343 /// [`Event::PaymentSent`] for obtaining the payment preimage.
344 PaymentPathSuccessful {
345 /// The id returned by [`ChannelManager::send_payment`] and used with
346 /// [`ChannelManager::retry_payment`].
348 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
349 /// [`ChannelManager::retry_payment`]: crate::ln::channelmanager::ChannelManager::retry_payment
350 payment_id: PaymentId,
351 /// The hash that was given to [`ChannelManager::send_payment`].
353 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
354 payment_hash: Option<PaymentHash>,
355 /// The payment path that was successful.
357 /// May contain a closed channel if the HTLC sent along the path was fulfilled on chain.
362 impl Writeable for Event {
363 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
365 &Event::FundingGenerationReady { .. } => {
367 // We never write out FundingGenerationReady events as, upon disconnection, peers
368 // drop any channels which have not yet exchanged funding_signed.
370 &Event::PaymentReceived { ref payment_hash, ref amt, ref purpose } => {
372 let mut payment_secret = None;
373 let payment_preimage;
375 PaymentPurpose::InvoicePayment { payment_preimage: preimage, payment_secret: secret } => {
376 payment_secret = Some(secret);
377 payment_preimage = *preimage;
379 PaymentPurpose::SpontaneousPayment(preimage) => {
380 payment_preimage = Some(*preimage);
383 write_tlv_fields!(writer, {
384 (0, payment_hash, required),
385 (2, payment_secret, option),
387 (6, 0u64, required), // user_payment_id required for compatibility with 0.0.103 and earlier
388 (8, payment_preimage, option),
391 &Event::PaymentSent { ref payment_id, ref payment_preimage, ref payment_hash, ref fee_paid_msat } => {
393 write_tlv_fields!(writer, {
394 (0, payment_preimage, required),
395 (1, payment_hash, required),
396 (3, payment_id, option),
397 (5, fee_paid_msat, option),
400 &Event::PaymentPathFailed {
401 ref payment_id, ref payment_hash, ref rejected_by_dest, ref network_update,
402 ref all_paths_failed, ref path, ref short_channel_id, ref retry,
410 error_code.write(writer)?;
412 error_data.write(writer)?;
413 write_tlv_fields!(writer, {
414 (0, payment_hash, required),
415 (1, network_update, option),
416 (2, rejected_by_dest, required),
417 (3, all_paths_failed, required),
419 (7, short_channel_id, option),
421 (11, payment_id, option),
424 &Event::PendingHTLCsForwardable { time_forwardable: _ } => {
426 // Note that we now ignore these on the read end as we'll re-generate them in
427 // ChannelManager, we write them here only for backwards compatibility.
429 &Event::SpendableOutputs { ref outputs } => {
431 write_tlv_fields!(writer, {
432 (0, VecWriteWrapper(outputs), required),
435 &Event::PaymentForwarded { fee_earned_msat, claim_from_onchain_tx } => {
437 write_tlv_fields!(writer, {
438 (0, fee_earned_msat, option),
439 (2, claim_from_onchain_tx, required),
442 &Event::ChannelClosed { ref channel_id, ref user_channel_id, ref reason } => {
444 write_tlv_fields!(writer, {
445 (0, channel_id, required),
446 (1, user_channel_id, required),
447 (2, reason, required)
450 &Event::DiscardFunding { ref channel_id, ref transaction } => {
452 write_tlv_fields!(writer, {
453 (0, channel_id, required),
454 (2, transaction, required)
457 &Event::PaymentPathSuccessful { ref payment_id, ref payment_hash, ref path } => {
459 write_tlv_fields!(writer, {
460 (0, payment_id, required),
461 (2, payment_hash, option),
465 // Note that, going forward, all new events must only write data inside of
466 // `write_tlv_fields`. Versions 0.0.101+ will ignore odd-numbered events that write
467 // data via `write_tlv_fields`.
472 impl MaybeReadable for Event {
473 fn read<R: io::Read>(reader: &mut R) -> Result<Option<Self>, msgs::DecodeError> {
474 match Readable::read(reader)? {
475 // Note that we do not write a length-prefixed TLV for FundingGenerationReady events,
476 // unlike all other events, thus we return immediately here.
480 let mut payment_hash = PaymentHash([0; 32]);
481 let mut payment_preimage = None;
482 let mut payment_secret = None;
484 let mut _user_payment_id = None::<u64>; // For compatibility with 0.0.103 and earlier
485 read_tlv_fields!(reader, {
486 (0, payment_hash, required),
487 (2, payment_secret, option),
489 (6, _user_payment_id, option),
490 (8, payment_preimage, option),
492 let purpose = match payment_secret {
493 Some(secret) => PaymentPurpose::InvoicePayment {
495 payment_secret: secret
497 None if payment_preimage.is_some() => PaymentPurpose::SpontaneousPayment(payment_preimage.unwrap()),
498 None => return Err(msgs::DecodeError::InvalidValue),
500 Ok(Some(Event::PaymentReceived {
510 let mut payment_preimage = PaymentPreimage([0; 32]);
511 let mut payment_hash = None;
512 let mut payment_id = None;
513 let mut fee_paid_msat = None;
514 read_tlv_fields!(reader, {
515 (0, payment_preimage, required),
516 (1, payment_hash, option),
517 (3, payment_id, option),
518 (5, fee_paid_msat, option),
520 if payment_hash.is_none() {
521 payment_hash = Some(PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()));
523 Ok(Some(Event::PaymentSent {
526 payment_hash: payment_hash.unwrap(),
535 let error_code = Readable::read(reader)?;
537 let error_data = Readable::read(reader)?;
538 let mut payment_hash = PaymentHash([0; 32]);
539 let mut rejected_by_dest = false;
540 let mut network_update = None;
541 let mut all_paths_failed = Some(true);
542 let mut path: Option<Vec<RouteHop>> = Some(vec![]);
543 let mut short_channel_id = None;
544 let mut retry = None;
545 let mut payment_id = None;
546 read_tlv_fields!(reader, {
547 (0, payment_hash, required),
548 (1, network_update, ignorable),
549 (2, rejected_by_dest, required),
550 (3, all_paths_failed, option),
552 (7, short_channel_id, option),
554 (11, payment_id, option),
556 Ok(Some(Event::PaymentPathFailed {
561 all_paths_failed: all_paths_failed.unwrap(),
576 let mut outputs = VecReadWrapper(Vec::new());
577 read_tlv_fields!(reader, {
578 (0, outputs, required),
580 Ok(Some(Event::SpendableOutputs { outputs: outputs.0 }))
586 let mut fee_earned_msat = None;
587 let mut claim_from_onchain_tx = false;
588 read_tlv_fields!(reader, {
589 (0, fee_earned_msat, option),
590 (2, claim_from_onchain_tx, required),
592 Ok(Some(Event::PaymentForwarded { fee_earned_msat, claim_from_onchain_tx }))
598 let mut channel_id = [0; 32];
599 let mut reason = None;
600 let mut user_channel_id_opt = None;
601 read_tlv_fields!(reader, {
602 (0, channel_id, required),
603 (1, user_channel_id_opt, option),
604 (2, reason, ignorable),
606 if reason.is_none() { return Ok(None); }
607 let user_channel_id = if let Some(id) = user_channel_id_opt { id } else { 0 };
608 Ok(Some(Event::ChannelClosed { channel_id, user_channel_id, reason: reason.unwrap() }))
614 let mut channel_id = [0; 32];
615 let mut transaction = Transaction{ version: 2, lock_time: 0, input: Vec::new(), output: Vec::new() };
616 read_tlv_fields!(reader, {
617 (0, channel_id, required),
618 (2, transaction, required),
620 Ok(Some(Event::DiscardFunding { channel_id, transaction } ))
626 let mut payment_id = PaymentId([0; 32]);
627 let mut payment_hash = None;
628 let mut path: Option<Vec<RouteHop>> = Some(vec![]);
629 read_tlv_fields!(reader, {
630 (0, payment_id, required),
631 (2, payment_hash, option),
634 Ok(Some(Event::PaymentPathSuccessful {
642 // Versions prior to 0.0.100 did not ignore odd types, instead returning InvalidValue.
643 // Version 0.0.100 failed to properly ignore odd types, possibly resulting in corrupt
646 // If the event is of unknown type, assume it was written with `write_tlv_fields`,
647 // which prefixes the whole thing with a length BigSize. Because the event is
648 // odd-type unknown, we should treat it as `Ok(None)` even if it has some TLV
649 // fields that are even. Thus, we avoid using `read_tlv_fields` and simply read
650 // exactly the number of bytes specified, ignoring them entirely.
651 let tlv_len: BigSize = Readable::read(reader)?;
652 FixedLengthReader::new(reader, tlv_len.0)
653 .eat_remaining().map_err(|_| msgs::DecodeError::ShortRead)?;
656 _ => Err(msgs::DecodeError::InvalidValue)
661 /// An event generated by ChannelManager which indicates a message should be sent to a peer (or
662 /// broadcast to most peers).
663 /// These events are handled by PeerManager::process_events if you are using a PeerManager.
664 #[derive(Clone, Debug)]
665 pub enum MessageSendEvent {
666 /// Used to indicate that we've accepted a channel open and should send the accept_channel
667 /// message provided to the given peer.
669 /// The node_id of the node which should receive this message
671 /// The message which should be sent.
672 msg: msgs::AcceptChannel,
674 /// Used to indicate that we've initiated a channel open and should send the open_channel
675 /// message provided to the given peer.
677 /// The node_id of the node which should receive this message
679 /// The message which should be sent.
680 msg: msgs::OpenChannel,
682 /// Used to indicate that a funding_created message should be sent to the peer with the given node_id.
684 /// The node_id of the node which should receive this message
686 /// The message which should be sent.
687 msg: msgs::FundingCreated,
689 /// Used to indicate that a funding_signed message should be sent to the peer with the given node_id.
691 /// The node_id of the node which should receive this message
693 /// The message which should be sent.
694 msg: msgs::FundingSigned,
696 /// Used to indicate that a funding_locked message should be sent to the peer with the given node_id.
698 /// The node_id of the node which should receive these message(s)
700 /// The funding_locked message which should be sent.
701 msg: msgs::FundingLocked,
703 /// Used to indicate that an announcement_signatures message should be sent to the peer with the given node_id.
704 SendAnnouncementSignatures {
705 /// The node_id of the node which should receive these message(s)
707 /// The announcement_signatures message which should be sent.
708 msg: msgs::AnnouncementSignatures,
710 /// Used to indicate that a series of HTLC update messages, as well as a commitment_signed
711 /// message should be sent to the peer with the given node_id.
713 /// The node_id of the node which should receive these message(s)
715 /// The update messages which should be sent. ALL messages in the struct should be sent!
716 updates: msgs::CommitmentUpdate,
718 /// Used to indicate that a revoke_and_ack message should be sent to the peer with the given node_id.
720 /// The node_id of the node which should receive this message
722 /// The message which should be sent.
723 msg: msgs::RevokeAndACK,
725 /// Used to indicate that a closing_signed message should be sent to the peer with the given node_id.
727 /// The node_id of the node which should receive this message
729 /// The message which should be sent.
730 msg: msgs::ClosingSigned,
732 /// Used to indicate that a shutdown message should be sent to the peer with the given node_id.
734 /// The node_id of the node which should receive this message
736 /// The message which should be sent.
739 /// Used to indicate that a channel_reestablish message should be sent to the peer with the given node_id.
740 SendChannelReestablish {
741 /// The node_id of the node which should receive this message
743 /// The message which should be sent.
744 msg: msgs::ChannelReestablish,
746 /// Used to indicate that a channel_announcement and channel_update should be broadcast to all
747 /// peers (except the peer with node_id either msg.contents.node_id_1 or msg.contents.node_id_2).
749 /// Note that after doing so, you very likely (unless you did so very recently) want to call
750 /// ChannelManager::broadcast_node_announcement to trigger a BroadcastNodeAnnouncement event.
751 /// This ensures that any nodes which see our channel_announcement also have a relevant
752 /// node_announcement, including relevant feature flags which may be important for routing
753 /// through or to us.
754 BroadcastChannelAnnouncement {
755 /// The channel_announcement which should be sent.
756 msg: msgs::ChannelAnnouncement,
757 /// The followup channel_update which should be sent.
758 update_msg: msgs::ChannelUpdate,
760 /// Used to indicate that a node_announcement should be broadcast to all peers.
761 BroadcastNodeAnnouncement {
762 /// The node_announcement which should be sent.
763 msg: msgs::NodeAnnouncement,
765 /// Used to indicate that a channel_update should be broadcast to all peers.
766 BroadcastChannelUpdate {
767 /// The channel_update which should be sent.
768 msg: msgs::ChannelUpdate,
770 /// Used to indicate that a channel_update should be sent to a single peer.
771 /// In contrast to [`Self::BroadcastChannelUpdate`], this is used when the channel is a
772 /// private channel and we shouldn't be informing all of our peers of channel parameters.
774 /// The node_id of the node which should receive this message
776 /// The channel_update which should be sent.
777 msg: msgs::ChannelUpdate,
779 /// Broadcast an error downstream to be handled
781 /// The node_id of the node which should receive this message
783 /// The action which should be taken.
784 action: msgs::ErrorAction
786 /// Query a peer for channels with funding transaction UTXOs in a block range.
787 SendChannelRangeQuery {
788 /// The node_id of this message recipient
790 /// The query_channel_range which should be sent.
791 msg: msgs::QueryChannelRange,
793 /// Request routing gossip messages from a peer for a list of channels identified by
794 /// their short_channel_ids.
796 /// The node_id of this message recipient
798 /// The query_short_channel_ids which should be sent.
799 msg: msgs::QueryShortChannelIds,
801 /// Sends a reply to a channel range query. This may be one of several SendReplyChannelRange events
802 /// emitted during processing of the query.
803 SendReplyChannelRange {
804 /// The node_id of this message recipient
806 /// The reply_channel_range which should be sent.
807 msg: msgs::ReplyChannelRange,
811 /// A trait indicating an object may generate message send events
812 pub trait MessageSendEventsProvider {
813 /// Gets the list of pending events which were generated by previous actions, clearing the list
815 fn get_and_clear_pending_msg_events(&self) -> Vec<MessageSendEvent>;
818 /// A trait indicating an object may generate events.
820 /// Events are processed by passing an [`EventHandler`] to [`process_pending_events`].
824 /// See [`process_pending_events`] for requirements around event processing.
826 /// When using this trait, [`process_pending_events`] will call [`handle_event`] for each pending
827 /// event since the last invocation. The handler must either act upon the event immediately
828 /// or preserve it for later handling.
830 /// Note, handlers may call back into the provider and thus deadlocking must be avoided. Be sure to
831 /// consult the provider's documentation on the implication of processing events and how a handler
832 /// may safely use the provider (e.g., see [`ChannelManager::process_pending_events`] and
833 /// [`ChainMonitor::process_pending_events`]).
835 /// (C-not implementable) As there is likely no reason for a user to implement this trait on their
838 /// [`process_pending_events`]: Self::process_pending_events
839 /// [`handle_event`]: EventHandler::handle_event
840 /// [`ChannelManager::process_pending_events`]: crate::ln::channelmanager::ChannelManager#method.process_pending_events
841 /// [`ChainMonitor::process_pending_events`]: crate::chain::chainmonitor::ChainMonitor#method.process_pending_events
842 pub trait EventsProvider {
843 /// Processes any events generated since the last call using the given event handler.
845 /// Subsequent calls must only process new events. However, handlers must be capable of handling
846 /// duplicate events across process restarts. This may occur if the provider was recovered from
847 /// an old state (i.e., it hadn't been successfully persisted after processing pending events).
848 fn process_pending_events<H: Deref>(&self, handler: H) where H::Target: EventHandler;
851 /// A trait implemented for objects handling events from [`EventsProvider`].
852 pub trait EventHandler {
853 /// Handles the given [`Event`].
855 /// See [`EventsProvider`] for details that must be considered when implementing this method.
856 fn handle_event(&self, event: &Event);
859 impl<F> EventHandler for F where F: Fn(&Event) {
860 fn handle_event(&self, event: &Event) {
865 impl<T: EventHandler> EventHandler for Arc<T> {
866 fn handle_event(&self, event: &Event) {
867 self.deref().handle_event(event)