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 core::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).
99 /// The preimage to the hash given to ChannelManager::send_payment.
100 /// Note that this serves as a payment receipt, if you wish to have such a thing, you must
101 /// store it somehow!
102 payment_preimage: PaymentPreimage,
104 /// Indicates an outbound payment we made failed. Probably some intermediary node dropped
105 /// something. You may wish to retry with a different route.
107 /// The hash which was given to ChannelManager::send_payment.
108 payment_hash: PaymentHash,
109 /// Indicates the payment was rejected for some reason by the recipient. This implies that
110 /// the payment has failed, not just the route in question. If this is not set, you may
111 /// retry the payment via a different route.
112 rejected_by_dest: bool,
114 error_code: Option<u16>,
116 error_data: Option<Vec<u8>>,
118 /// Used to indicate that ChannelManager::process_pending_htlc_forwards should be called at a
119 /// time in the future.
120 PendingHTLCsForwardable {
121 /// The minimum amount of time that should be waited prior to calling
122 /// process_pending_htlc_forwards. To increase the effort required to correlate payments,
123 /// you should wait a random amount of time in roughly the range (now + time_forwardable,
124 /// now + 5*time_forwardable).
125 time_forwardable: Duration,
127 /// Used to indicate that an output was generated on-chain which you should know how to spend.
128 /// Such an output will *not* ever be spent by rust-lightning, and are not at risk of your
129 /// counterparty spending them due to some kind of timeout. Thus, you need to store them
130 /// somewhere and spend them when you create on-chain transactions.
132 /// The outputs which you should store as spendable by you.
133 outputs: Vec<SpendableOutputDescriptor>,
137 impl Writeable for Event {
138 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
140 &Event::FundingGenerationReady { .. } => {
142 // We never write out FundingGenerationReady events as, upon disconnection, peers
143 // drop any channels which have not yet exchanged funding_signed.
145 &Event::PaymentReceived { ref payment_hash, ref payment_preimage, ref payment_secret, ref amt, ref user_payment_id } => {
147 payment_hash.write(writer)?;
148 payment_preimage.write(writer)?;
149 payment_secret.write(writer)?;
151 user_payment_id.write(writer)?;
153 &Event::PaymentSent { ref payment_preimage } => {
155 payment_preimage.write(writer)?;
157 &Event::PaymentFailed { ref payment_hash, ref rejected_by_dest,
164 payment_hash.write(writer)?;
165 rejected_by_dest.write(writer)?;
167 error_code.write(writer)?;
169 error_data.write(writer)?;
171 &Event::PendingHTLCsForwardable { time_forwardable: _ } => {
173 // We don't write the time_fordwardable out at all, as we presume when the user
174 // deserializes us at least that much time has elapsed.
176 &Event::SpendableOutputs { ref outputs } => {
178 (outputs.len() as u64).write(writer)?;
179 for output in outputs.iter() {
180 output.write(writer)?;
187 impl MaybeReadable for Event {
188 fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Option<Self>, msgs::DecodeError> {
189 match Readable::read(reader)? {
191 1u8 => Ok(Some(Event::PaymentReceived {
192 payment_hash: Readable::read(reader)?,
193 payment_preimage: Readable::read(reader)?,
194 payment_secret: Readable::read(reader)?,
195 amt: Readable::read(reader)?,
196 user_payment_id: Readable::read(reader)?,
198 2u8 => Ok(Some(Event::PaymentSent {
199 payment_preimage: Readable::read(reader)?,
201 3u8 => Ok(Some(Event::PaymentFailed {
202 payment_hash: Readable::read(reader)?,
203 rejected_by_dest: Readable::read(reader)?,
205 error_code: Readable::read(reader)?,
207 error_data: Readable::read(reader)?,
209 4u8 => Ok(Some(Event::PendingHTLCsForwardable {
210 time_forwardable: Duration::from_secs(0)
213 let outputs_len: u64 = Readable::read(reader)?;
214 let mut outputs = Vec::new();
215 for _ in 0..outputs_len {
216 outputs.push(Readable::read(reader)?);
218 Ok(Some(Event::SpendableOutputs { outputs }))
220 _ => Err(msgs::DecodeError::InvalidValue)
225 /// An event generated by ChannelManager which indicates a message should be sent to a peer (or
226 /// broadcast to most peers).
227 /// These events are handled by PeerManager::process_events if you are using a PeerManager.
228 #[derive(Clone, Debug)]
229 pub enum MessageSendEvent {
230 /// Used to indicate that we've accepted a channel open and should send the accept_channel
231 /// message provided to the given peer.
233 /// The node_id of the node which should receive this message
235 /// The message which should be sent.
236 msg: msgs::AcceptChannel,
238 /// Used to indicate that we've initiated a channel open and should send the open_channel
239 /// message provided to the given peer.
241 /// The node_id of the node which should receive this message
243 /// The message which should be sent.
244 msg: msgs::OpenChannel,
246 /// Used to indicate that a funding_created message should be sent to the peer with the given node_id.
248 /// The node_id of the node which should receive this message
250 /// The message which should be sent.
251 msg: msgs::FundingCreated,
253 /// Used to indicate that a funding_signed message should be sent to the peer with the given node_id.
255 /// The node_id of the node which should receive this message
257 /// The message which should be sent.
258 msg: msgs::FundingSigned,
260 /// Used to indicate that a funding_locked message should be sent to the peer with the given node_id.
262 /// The node_id of the node which should receive these message(s)
264 /// The funding_locked message which should be sent.
265 msg: msgs::FundingLocked,
267 /// Used to indicate that an announcement_signatures message should be sent to the peer with the given node_id.
268 SendAnnouncementSignatures {
269 /// The node_id of the node which should receive these message(s)
271 /// The announcement_signatures message which should be sent.
272 msg: msgs::AnnouncementSignatures,
274 /// Used to indicate that a series of HTLC update messages, as well as a commitment_signed
275 /// message should be sent to the peer with the given node_id.
277 /// The node_id of the node which should receive these message(s)
279 /// The update messages which should be sent. ALL messages in the struct should be sent!
280 updates: msgs::CommitmentUpdate,
282 /// Used to indicate that a revoke_and_ack message should be sent to the peer with the given node_id.
284 /// The node_id of the node which should receive this message
286 /// The message which should be sent.
287 msg: msgs::RevokeAndACK,
289 /// Used to indicate that a closing_signed message should be sent to the peer with the given node_id.
291 /// The node_id of the node which should receive this message
293 /// The message which should be sent.
294 msg: msgs::ClosingSigned,
296 /// Used to indicate that a shutdown message should be sent to the peer with the given node_id.
298 /// The node_id of the node which should receive this message
300 /// The message which should be sent.
303 /// Used to indicate that a channel_reestablish message should be sent to the peer with the given node_id.
304 SendChannelReestablish {
305 /// The node_id of the node which should receive this message
307 /// The message which should be sent.
308 msg: msgs::ChannelReestablish,
310 /// Used to indicate that a channel_announcement and channel_update should be broadcast to all
311 /// peers (except the peer with node_id either msg.contents.node_id_1 or msg.contents.node_id_2).
313 /// Note that after doing so, you very likely (unless you did so very recently) want to call
314 /// ChannelManager::broadcast_node_announcement to trigger a BroadcastNodeAnnouncement event.
315 /// This ensures that any nodes which see our channel_announcement also have a relevant
316 /// node_announcement, including relevant feature flags which may be important for routing
317 /// through or to us.
318 BroadcastChannelAnnouncement {
319 /// The channel_announcement which should be sent.
320 msg: msgs::ChannelAnnouncement,
321 /// The followup channel_update which should be sent.
322 update_msg: msgs::ChannelUpdate,
324 /// Used to indicate that a node_announcement should be broadcast to all peers.
325 BroadcastNodeAnnouncement {
326 /// The node_announcement which should be sent.
327 msg: msgs::NodeAnnouncement,
329 /// Used to indicate that a channel_update should be broadcast to all peers.
330 BroadcastChannelUpdate {
331 /// The channel_update which should be sent.
332 msg: msgs::ChannelUpdate,
334 /// Broadcast an error downstream to be handled
336 /// The node_id of the node which should receive this message
338 /// The action which should be taken.
339 action: msgs::ErrorAction
341 /// When a payment fails we may receive updates back from the hop where it failed. In such
342 /// cases this event is generated so that we can inform the network graph of this information.
343 PaymentFailureNetworkUpdate {
344 /// The channel/node update which should be sent to NetGraphMsgHandler
345 update: msgs::HTLCFailChannelUpdate,
347 /// Query a peer for channels with funding transaction UTXOs in a block range.
348 SendChannelRangeQuery {
349 /// The node_id of this message recipient
351 /// The query_channel_range which should be sent.
352 msg: msgs::QueryChannelRange,
354 /// Request routing gossip messages from a peer for a list of channels identified by
355 /// their short_channel_ids.
357 /// The node_id of this message recipient
359 /// The query_short_channel_ids which should be sent.
360 msg: msgs::QueryShortChannelIds,
362 /// Sends a reply to a channel range query. This may be one of several SendReplyChannelRange events
363 /// emitted during processing of the query.
364 SendReplyChannelRange {
365 /// The node_id of this message recipient
367 /// The reply_channel_range which should be sent.
368 msg: msgs::ReplyChannelRange,
372 /// A trait indicating an object may generate message send events
373 pub trait MessageSendEventsProvider {
374 /// Gets the list of pending events which were generated by previous actions, clearing the list
376 fn get_and_clear_pending_msg_events(&self) -> Vec<MessageSendEvent>;
379 /// A trait indicating an object may generate events
380 pub trait EventsProvider {
381 /// Gets the list of pending events which were generated by previous actions, clearing the list
383 fn get_and_clear_pending_events(&self) -> Vec<Event>;