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
18 use ln::{PaymentPreimage, PaymentHash, PaymentSecret};
19 use chain::keysinterface::SpendableOutputDescriptor;
20 use util::ser::{Writeable, Writer, MaybeReadable, Readable};
22 use bitcoin::blockdata::script::Script;
24 use bitcoin::secp256k1::key::PublicKey;
26 use std::time::Duration;
28 /// An Event which you should probably take some action in response to.
30 /// Note that while Writeable and Readable are implemented for Event, you probably shouldn't use
31 /// them directly as they don't round-trip exactly (for example FundingGenerationReady is never
32 /// written as it makes no sense to respond to it after reconnecting to peers).
33 #[derive(Clone, Debug)]
35 /// Used to indicate that the client should generate a funding transaction with the given
36 /// parameters and then call ChannelManager::funding_transaction_generated.
37 /// Generated in ChannelManager message handling.
38 /// Note that *all inputs* in the funding transaction must spend SegWit outputs or your
39 /// counterparty can steal your funds!
40 FundingGenerationReady {
41 /// The random channel_id we picked which you'll need to pass into
42 /// ChannelManager::funding_transaction_generated.
43 temporary_channel_id: [u8; 32],
44 /// The value, in satoshis, that the output should have.
45 channel_value_satoshis: u64,
46 /// The script which should be used in the transaction output.
47 output_script: Script,
48 /// The value passed in to ChannelManager::create_channel
51 /// Indicates we've received money! Just gotta dig out that payment preimage and feed it to
52 /// ChannelManager::claim_funds to get it....
53 /// Note that if the preimage is not known or the amount paid is incorrect, you should call
54 /// ChannelManager::fail_htlc_backwards to free up resources for this HTLC and avoid
55 /// network congestion.
56 /// The amount paid should be considered 'incorrect' when it is less than or more than twice
57 /// the amount expected.
58 /// If you fail to call either ChannelManager::claim_funds or
59 /// ChannelManager::fail_htlc_backwards within the HTLC's timeout, the HTLC will be
60 /// automatically failed.
62 /// The hash for which the preimage should be handed to the ChannelManager.
63 payment_hash: PaymentHash,
64 /// The preimage to the payment_hash, if the payment hash (and secret) were fetched via
65 /// [`ChannelManager::create_inbound_payment`]. If provided, this can be handed directly to
66 /// [`ChannelManager::claim_funds`].
68 /// [`ChannelManager::create_inbound_payment`]: crate::ln::channelmanager::ChannelManager::create_inbound_payment
69 /// [`ChannelManager::claim_funds`]: crate::ln::channelmanager::ChannelManager::claim_funds
70 payment_preimage: Option<PaymentPreimage>,
71 /// The "payment secret". This authenticates the sender to the recipient, preventing a
72 /// number of deanonymization attacks during the routing process.
73 /// It is provided here for your reference, however its accuracy is enforced directly by
74 /// [`ChannelManager`] using the values you previously provided to
75 /// [`ChannelManager::create_inbound_payment`] or
76 /// [`ChannelManager::create_inbound_payment_for_hash`].
78 /// [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
79 /// [`ChannelManager::create_inbound_payment`]: crate::ln::channelmanager::ChannelManager::create_inbound_payment
80 /// [`ChannelManager::create_inbound_payment_for_hash`]: crate::ln::channelmanager::ChannelManager::create_inbound_payment_for_hash
81 payment_secret: PaymentSecret,
82 /// The value, in thousandths of a satoshi, that this payment is for. Note that you must
83 /// compare this to the expected value before accepting the payment (as otherwise you are
84 /// providing proof-of-payment for less than the value you expected!).
86 /// This is the `user_payment_id` which was provided to
87 /// [`ChannelManager::create_inbound_payment_for_hash`] or
88 /// [`ChannelManager::create_inbound_payment`]. It has no meaning inside of LDK and is
89 /// simply copied here. It may be used to correlate PaymentReceived events with invoice
90 /// metadata stored elsewhere.
92 /// [`ChannelManager::create_inbound_payment`]: crate::ln::channelmanager::ChannelManager::create_inbound_payment
93 /// [`ChannelManager::create_inbound_payment_for_hash`]: crate::ln::channelmanager::ChannelManager::create_inbound_payment_for_hash
96 /// Indicates an outbound payment we made succeeded (ie it made it all the way to its target
97 /// and we got back the payment preimage for it).
98 /// Note that duplicative PaymentSent Events may be generated - it is your responsibility to
99 /// deduplicate them by payment_preimage (which MUST be unique)!
101 /// The preimage to the hash given to ChannelManager::send_payment.
102 /// Note that this serves as a payment receipt, if you wish to have such a thing, you must
103 /// store it somehow!
104 payment_preimage: PaymentPreimage,
106 /// Indicates an outbound payment we made failed. Probably some intermediary node dropped
107 /// something. You may wish to retry with a different route.
108 /// Note that duplicative PaymentFailed Events may be generated - it is your responsibility to
109 /// deduplicate them by payment_hash (which MUST be unique)!
111 /// The hash which was given to ChannelManager::send_payment.
112 payment_hash: PaymentHash,
113 /// Indicates the payment was rejected for some reason by the recipient. This implies that
114 /// the payment has failed, not just the route in question. If this is not set, you may
115 /// retry the payment via a different route.
116 rejected_by_dest: bool,
118 error_code: Option<u16>,
120 error_data: Option<Vec<u8>>,
122 /// Used to indicate that ChannelManager::process_pending_htlc_forwards should be called at a
123 /// time in the future.
124 PendingHTLCsForwardable {
125 /// The minimum amount of time that should be waited prior to calling
126 /// process_pending_htlc_forwards. To increase the effort required to correlate payments,
127 /// you should wait a random amount of time in roughly the range (now + time_forwardable,
128 /// now + 5*time_forwardable).
129 time_forwardable: Duration,
131 /// Used to indicate that an output was generated on-chain which you should know how to spend.
132 /// Such an output will *not* ever be spent by rust-lightning, and are not at risk of your
133 /// counterparty spending them due to some kind of timeout. Thus, you need to store them
134 /// somewhere and spend them when you create on-chain transactions.
136 /// The outputs which you should store as spendable by you.
137 outputs: Vec<SpendableOutputDescriptor>,
141 impl Writeable for Event {
142 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
144 &Event::FundingGenerationReady { .. } => {
146 // We never write out FundingGenerationReady events as, upon disconnection, peers
147 // drop any channels which have not yet exchanged funding_signed.
149 &Event::PaymentReceived { ref payment_hash, ref payment_preimage, ref payment_secret, ref amt, ref user_payment_id } => {
151 payment_hash.write(writer)?;
152 payment_preimage.write(writer)?;
153 payment_secret.write(writer)?;
155 user_payment_id.write(writer)?;
157 &Event::PaymentSent { ref payment_preimage } => {
159 payment_preimage.write(writer)?;
161 &Event::PaymentFailed { ref payment_hash, ref rejected_by_dest,
168 payment_hash.write(writer)?;
169 rejected_by_dest.write(writer)?;
171 error_code.write(writer)?;
173 error_data.write(writer)?;
175 &Event::PendingHTLCsForwardable { time_forwardable: _ } => {
177 // We don't write the time_fordwardable out at all, as we presume when the user
178 // deserializes us at least that much time has elapsed.
180 &Event::SpendableOutputs { ref outputs } => {
182 (outputs.len() as u64).write(writer)?;
183 for output in outputs.iter() {
184 output.write(writer)?;
191 impl MaybeReadable for Event {
192 fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Option<Self>, msgs::DecodeError> {
193 match Readable::read(reader)? {
195 1u8 => Ok(Some(Event::PaymentReceived {
196 payment_hash: Readable::read(reader)?,
197 payment_preimage: Readable::read(reader)?,
198 payment_secret: Readable::read(reader)?,
199 amt: Readable::read(reader)?,
200 user_payment_id: Readable::read(reader)?,
202 2u8 => Ok(Some(Event::PaymentSent {
203 payment_preimage: Readable::read(reader)?,
205 3u8 => Ok(Some(Event::PaymentFailed {
206 payment_hash: Readable::read(reader)?,
207 rejected_by_dest: Readable::read(reader)?,
209 error_code: Readable::read(reader)?,
211 error_data: Readable::read(reader)?,
213 4u8 => Ok(Some(Event::PendingHTLCsForwardable {
214 time_forwardable: Duration::from_secs(0)
217 let outputs_len: u64 = Readable::read(reader)?;
218 let mut outputs = Vec::new();
219 for _ in 0..outputs_len {
220 outputs.push(Readable::read(reader)?);
222 Ok(Some(Event::SpendableOutputs { outputs }))
224 _ => Err(msgs::DecodeError::InvalidValue)
229 /// An event generated by ChannelManager which indicates a message should be sent to a peer (or
230 /// broadcast to most peers).
231 /// These events are handled by PeerManager::process_events if you are using a PeerManager.
232 #[derive(Clone, Debug)]
233 pub enum MessageSendEvent {
234 /// Used to indicate that we've accepted a channel open and should send the accept_channel
235 /// message provided to the given peer.
237 /// The node_id of the node which should receive this message
239 /// The message which should be sent.
240 msg: msgs::AcceptChannel,
242 /// Used to indicate that we've initiated a channel open and should send the open_channel
243 /// message provided to the given peer.
245 /// The node_id of the node which should receive this message
247 /// The message which should be sent.
248 msg: msgs::OpenChannel,
250 /// Used to indicate that a funding_created message should be sent to the peer with the given node_id.
252 /// The node_id of the node which should receive this message
254 /// The message which should be sent.
255 msg: msgs::FundingCreated,
257 /// Used to indicate that a funding_signed message should be sent to the peer with the given node_id.
259 /// The node_id of the node which should receive this message
261 /// The message which should be sent.
262 msg: msgs::FundingSigned,
264 /// Used to indicate that a funding_locked message should be sent to the peer with the given node_id.
266 /// The node_id of the node which should receive these message(s)
268 /// The funding_locked message which should be sent.
269 msg: msgs::FundingLocked,
271 /// Used to indicate that an announcement_signatures message should be sent to the peer with the given node_id.
272 SendAnnouncementSignatures {
273 /// The node_id of the node which should receive these message(s)
275 /// The announcement_signatures message which should be sent.
276 msg: msgs::AnnouncementSignatures,
278 /// Used to indicate that a series of HTLC update messages, as well as a commitment_signed
279 /// message should be sent to the peer with the given node_id.
281 /// The node_id of the node which should receive these message(s)
283 /// The update messages which should be sent. ALL messages in the struct should be sent!
284 updates: msgs::CommitmentUpdate,
286 /// Used to indicate that a revoke_and_ack message should be sent to the peer with the given node_id.
288 /// The node_id of the node which should receive this message
290 /// The message which should be sent.
291 msg: msgs::RevokeAndACK,
293 /// Used to indicate that a closing_signed message should be sent to the peer with the given node_id.
295 /// The node_id of the node which should receive this message
297 /// The message which should be sent.
298 msg: msgs::ClosingSigned,
300 /// Used to indicate that a shutdown message should be sent to the peer with the given node_id.
302 /// The node_id of the node which should receive this message
304 /// The message which should be sent.
307 /// Used to indicate that a channel_reestablish message should be sent to the peer with the given node_id.
308 SendChannelReestablish {
309 /// The node_id of the node which should receive this message
311 /// The message which should be sent.
312 msg: msgs::ChannelReestablish,
314 /// Used to indicate that a channel_announcement and channel_update should be broadcast to all
315 /// peers (except the peer with node_id either msg.contents.node_id_1 or msg.contents.node_id_2).
317 /// Note that after doing so, you very likely (unless you did so very recently) want to call
318 /// ChannelManager::broadcast_node_announcement to trigger a BroadcastNodeAnnouncement event.
319 /// This ensures that any nodes which see our channel_announcement also have a relevant
320 /// node_announcement, including relevant feature flags which may be important for routing
321 /// through or to us.
322 BroadcastChannelAnnouncement {
323 /// The channel_announcement which should be sent.
324 msg: msgs::ChannelAnnouncement,
325 /// The followup channel_update which should be sent.
326 update_msg: msgs::ChannelUpdate,
328 /// Used to indicate that a node_announcement should be broadcast to all peers.
329 BroadcastNodeAnnouncement {
330 /// The node_announcement which should be sent.
331 msg: msgs::NodeAnnouncement,
333 /// Used to indicate that a channel_update should be broadcast to all peers.
334 BroadcastChannelUpdate {
335 /// The channel_update which should be sent.
336 msg: msgs::ChannelUpdate,
338 /// Broadcast an error downstream to be handled
340 /// The node_id of the node which should receive this message
342 /// The action which should be taken.
343 action: msgs::ErrorAction
345 /// When a payment fails we may receive updates back from the hop where it failed. In such
346 /// cases this event is generated so that we can inform the network graph of this information.
347 PaymentFailureNetworkUpdate {
348 /// The channel/node update which should be sent to NetGraphMsgHandler
349 update: msgs::HTLCFailChannelUpdate,
351 /// Query a peer for channels with funding transaction UTXOs in a block range.
352 SendChannelRangeQuery {
353 /// The node_id of this message recipient
355 /// The query_channel_range which should be sent.
356 msg: msgs::QueryChannelRange,
358 /// Request routing gossip messages from a peer for a list of channels identified by
359 /// their short_channel_ids.
361 /// The node_id of this message recipient
363 /// The query_short_channel_ids which should be sent.
364 msg: msgs::QueryShortChannelIds,
366 /// Sends a reply to a channel range query. This may be one of several SendReplyChannelRange events
367 /// emitted during processing of the query.
368 SendReplyChannelRange {
369 /// The node_id of this message recipient
371 /// The reply_channel_range which should be sent.
372 msg: msgs::ReplyChannelRange,
376 /// A trait indicating an object may generate message send events
377 pub trait MessageSendEventsProvider {
378 /// Gets the list of pending events which were generated by previous actions, clearing the list
380 fn get_and_clear_pending_msg_events(&self) -> Vec<MessageSendEvent>;
383 /// A trait indicating an object may generate events
384 pub trait EventsProvider {
385 /// Gets the list of pending events which were generated by previous actions, clearing the list
387 fn get_and_clear_pending_events(&self) -> Vec<Event>;