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::channelmanager::{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 "payment secret". This authenticates the sender to the recipient, preventing a
65 /// number of deanonymization attacks during the routing process.
66 /// It is provided here for your reference, however its accuracy is enforced directly by
67 /// [`ChannelManager`] using the values you previously provided to
68 /// [`ChannelManager::create_inbound_payment`] or
69 /// [`ChannelManager::create_inbound_payment_for_hash`].
71 /// [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
72 /// [`ChannelManager::create_inbound_payment`]: crate::ln::channelmanager::ChannelManager::create_inbound_payment
73 /// [`ChannelManager::create_inbound_payment_for_hash`]: crate::ln::channelmanager::ChannelManager::create_inbound_payment_for_hash
74 payment_secret: PaymentSecret,
75 /// The value, in thousandths of a satoshi, that this payment is for. Note that you must
76 /// compare this to the expected value before accepting the payment (as otherwise you are
77 /// providing proof-of-payment for less than the value you expected!).
79 /// This is the `user_payment_id` which was provided to
80 /// [`ChannelManager::create_inbound_payment_for_hash`] or
81 /// [`ChannelManager::create_inbound_payment`]. It has no meaning inside of LDK and is
82 /// simply copied here. It may be used to correlate PaymentReceived events with invoice
83 /// metadata stored elsewhere.
85 /// [`ChannelManager::create_inbound_payment`]: crate::ln::channelmanager::ChannelManager::create_inbound_payment
86 /// [`ChannelManager::create_inbound_payment_for_hash`]: crate::ln::channelmanager::ChannelManager::create_inbound_payment_for_hash
89 /// Indicates an outbound payment we made succeeded (ie it made it all the way to its target
90 /// and we got back the payment preimage for it).
91 /// Note that duplicative PaymentSent Events may be generated - it is your responsibility to
92 /// deduplicate them by payment_preimage (which MUST be unique)!
94 /// The preimage to the hash given to ChannelManager::send_payment.
95 /// Note that this serves as a payment receipt, if you wish to have such a thing, you must
97 payment_preimage: PaymentPreimage,
99 /// Indicates an outbound payment we made failed. Probably some intermediary node dropped
100 /// something. You may wish to retry with a different route.
101 /// Note that duplicative PaymentFailed Events may be generated - it is your responsibility to
102 /// deduplicate them by payment_hash (which MUST be unique)!
104 /// The hash which was given to ChannelManager::send_payment.
105 payment_hash: PaymentHash,
106 /// Indicates the payment was rejected for some reason by the recipient. This implies that
107 /// the payment has failed, not just the route in question. If this is not set, you may
108 /// retry the payment via a different route.
109 rejected_by_dest: bool,
111 error_code: Option<u16>,
113 error_data: Option<Vec<u8>>,
115 /// Used to indicate that ChannelManager::process_pending_htlc_forwards should be called at a
116 /// time in the future.
117 PendingHTLCsForwardable {
118 /// The minimum amount of time that should be waited prior to calling
119 /// process_pending_htlc_forwards. To increase the effort required to correlate payments,
120 /// you should wait a random amount of time in roughly the range (now + time_forwardable,
121 /// now + 5*time_forwardable).
122 time_forwardable: Duration,
124 /// Used to indicate that an output was generated on-chain which you should know how to spend.
125 /// Such an output will *not* ever be spent by rust-lightning, and are not at risk of your
126 /// counterparty spending them due to some kind of timeout. Thus, you need to store them
127 /// somewhere and spend them when you create on-chain transactions.
129 /// The outputs which you should store as spendable by you.
130 outputs: Vec<SpendableOutputDescriptor>,
134 impl Writeable for Event {
135 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
137 &Event::FundingGenerationReady { .. } => {
139 // We never write out FundingGenerationReady events as, upon disconnection, peers
140 // drop any channels which have not yet exchanged funding_signed.
142 &Event::PaymentReceived { ref payment_hash, ref payment_secret, ref amt, ref user_payment_id } => {
144 payment_hash.write(writer)?;
145 payment_secret.write(writer)?;
147 user_payment_id.write(writer)?;
149 &Event::PaymentSent { ref payment_preimage } => {
151 payment_preimage.write(writer)?;
153 &Event::PaymentFailed { ref payment_hash, ref rejected_by_dest,
160 payment_hash.write(writer)?;
161 rejected_by_dest.write(writer)?;
163 error_code.write(writer)?;
165 error_data.write(writer)?;
167 &Event::PendingHTLCsForwardable { time_forwardable: _ } => {
169 // We don't write the time_fordwardable out at all, as we presume when the user
170 // deserializes us at least that much time has elapsed.
172 &Event::SpendableOutputs { ref outputs } => {
174 (outputs.len() as u64).write(writer)?;
175 for output in outputs.iter() {
176 output.write(writer)?;
183 impl MaybeReadable for Event {
184 fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Option<Self>, msgs::DecodeError> {
185 match Readable::read(reader)? {
187 1u8 => Ok(Some(Event::PaymentReceived {
188 payment_hash: Readable::read(reader)?,
189 payment_secret: Readable::read(reader)?,
190 amt: Readable::read(reader)?,
191 user_payment_id: Readable::read(reader)?,
193 2u8 => Ok(Some(Event::PaymentSent {
194 payment_preimage: Readable::read(reader)?,
196 3u8 => Ok(Some(Event::PaymentFailed {
197 payment_hash: Readable::read(reader)?,
198 rejected_by_dest: Readable::read(reader)?,
200 error_code: Readable::read(reader)?,
202 error_data: Readable::read(reader)?,
204 4u8 => Ok(Some(Event::PendingHTLCsForwardable {
205 time_forwardable: Duration::from_secs(0)
208 let outputs_len: u64 = Readable::read(reader)?;
209 let mut outputs = Vec::new();
210 for _ in 0..outputs_len {
211 outputs.push(Readable::read(reader)?);
213 Ok(Some(Event::SpendableOutputs { outputs }))
215 _ => Err(msgs::DecodeError::InvalidValue)
220 /// An event generated by ChannelManager which indicates a message should be sent to a peer (or
221 /// broadcast to most peers).
222 /// These events are handled by PeerManager::process_events if you are using a PeerManager.
223 #[derive(Clone, Debug)]
224 pub enum MessageSendEvent {
225 /// Used to indicate that we've accepted a channel open and should send the accept_channel
226 /// message provided to the given peer.
228 /// The node_id of the node which should receive this message
230 /// The message which should be sent.
231 msg: msgs::AcceptChannel,
233 /// Used to indicate that we've initiated a channel open and should send the open_channel
234 /// message provided to the given peer.
236 /// The node_id of the node which should receive this message
238 /// The message which should be sent.
239 msg: msgs::OpenChannel,
241 /// Used to indicate that a funding_created message should be sent to the peer with the given node_id.
243 /// The node_id of the node which should receive this message
245 /// The message which should be sent.
246 msg: msgs::FundingCreated,
248 /// Used to indicate that a funding_signed message should be sent to the peer with the given node_id.
250 /// The node_id of the node which should receive this message
252 /// The message which should be sent.
253 msg: msgs::FundingSigned,
255 /// Used to indicate that a funding_locked message should be sent to the peer with the given node_id.
257 /// The node_id of the node which should receive these message(s)
259 /// The funding_locked message which should be sent.
260 msg: msgs::FundingLocked,
262 /// Used to indicate that an announcement_signatures message should be sent to the peer with the given node_id.
263 SendAnnouncementSignatures {
264 /// The node_id of the node which should receive these message(s)
266 /// The announcement_signatures message which should be sent.
267 msg: msgs::AnnouncementSignatures,
269 /// Used to indicate that a series of HTLC update messages, as well as a commitment_signed
270 /// message should be sent to the peer with the given node_id.
272 /// The node_id of the node which should receive these message(s)
274 /// The update messages which should be sent. ALL messages in the struct should be sent!
275 updates: msgs::CommitmentUpdate,
277 /// Used to indicate that a revoke_and_ack message should be sent to the peer with the given node_id.
279 /// The node_id of the node which should receive this message
281 /// The message which should be sent.
282 msg: msgs::RevokeAndACK,
284 /// Used to indicate that a closing_signed message should be sent to the peer with the given node_id.
286 /// The node_id of the node which should receive this message
288 /// The message which should be sent.
289 msg: msgs::ClosingSigned,
291 /// Used to indicate that a shutdown message should be sent to the peer with the given node_id.
293 /// The node_id of the node which should receive this message
295 /// The message which should be sent.
298 /// Used to indicate that a channel_reestablish message should be sent to the peer with the given node_id.
299 SendChannelReestablish {
300 /// The node_id of the node which should receive this message
302 /// The message which should be sent.
303 msg: msgs::ChannelReestablish,
305 /// Used to indicate that a channel_announcement and channel_update should be broadcast to all
306 /// peers (except the peer with node_id either msg.contents.node_id_1 or msg.contents.node_id_2).
308 /// Note that after doing so, you very likely (unless you did so very recently) want to call
309 /// ChannelManager::broadcast_node_announcement to trigger a BroadcastNodeAnnouncement event.
310 /// This ensures that any nodes which see our channel_announcement also have a relevant
311 /// node_announcement, including relevant feature flags which may be important for routing
312 /// through or to us.
313 BroadcastChannelAnnouncement {
314 /// The channel_announcement which should be sent.
315 msg: msgs::ChannelAnnouncement,
316 /// The followup channel_update which should be sent.
317 update_msg: msgs::ChannelUpdate,
319 /// Used to indicate that a node_announcement should be broadcast to all peers.
320 BroadcastNodeAnnouncement {
321 /// The node_announcement which should be sent.
322 msg: msgs::NodeAnnouncement,
324 /// Used to indicate that a channel_update should be broadcast to all peers.
325 BroadcastChannelUpdate {
326 /// The channel_update which should be sent.
327 msg: msgs::ChannelUpdate,
329 /// Broadcast an error downstream to be handled
331 /// The node_id of the node which should receive this message
333 /// The action which should be taken.
334 action: msgs::ErrorAction
336 /// When a payment fails we may receive updates back from the hop where it failed. In such
337 /// cases this event is generated so that we can inform the network graph of this information.
338 PaymentFailureNetworkUpdate {
339 /// The channel/node update which should be sent to NetGraphMsgHandler
340 update: msgs::HTLCFailChannelUpdate,
342 /// Query a peer for channels with funding transaction UTXOs in a block range.
343 SendChannelRangeQuery {
344 /// The node_id of this message recipient
346 /// The query_channel_range which should be sent.
347 msg: msgs::QueryChannelRange,
349 /// Request routing gossip messages from a peer for a list of channels identified by
350 /// their short_channel_ids.
352 /// The node_id of this message recipient
354 /// The query_short_channel_ids which should be sent.
355 msg: msgs::QueryShortChannelIds,
357 /// Sends a reply to a channel range query. This may be one of several SendReplyChannelRange events
358 /// emitted during processing of the query.
359 SendReplyChannelRange {
360 /// The node_id of this message recipient
362 /// The reply_channel_range which should be sent.
363 msg: msgs::ReplyChannelRange,
367 /// A trait indicating an object may generate message send events
368 pub trait MessageSendEventsProvider {
369 /// Gets the list of pending events which were generated by previous actions, clearing the list
371 fn get_and_clear_pending_msg_events(&self) -> Vec<MessageSendEvent>;
374 /// A trait indicating an object may generate events
375 pub trait EventsProvider {
376 /// Gets the list of pending events which were generated by previous actions, clearing the list
378 fn get_and_clear_pending_events(&self) -> Vec<Event>;