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::transaction::OutPoint;
20 use chain::keysinterface::SpendableOutputDescriptor;
21 use util::ser::{Writeable, Writer, MaybeReadable, Readable};
23 use bitcoin::blockdata::script::Script;
25 use bitcoin::secp256k1::key::PublicKey;
27 use std::time::Duration;
29 /// An Event which you should probably take some action in response to.
31 /// Note that while Writeable and Readable are implemented for Event, you probably shouldn't use
32 /// them directly as they don't round-trip exactly (for example FundingGenerationReady is never
33 /// written as it makes no sense to respond to it after reconnecting to peers).
34 #[derive(Clone, Debug)]
36 /// Used to indicate that the client should generate a funding transaction with the given
37 /// parameters and then call ChannelManager::funding_transaction_generated.
38 /// Generated in ChannelManager message handling.
39 /// Note that *all inputs* in the funding transaction must spend SegWit outputs or your
40 /// counterparty can steal your funds!
41 FundingGenerationReady {
42 /// The random channel_id we picked which you'll need to pass into
43 /// ChannelManager::funding_transaction_generated.
44 temporary_channel_id: [u8; 32],
45 /// The value, in satoshis, that the output should have.
46 channel_value_satoshis: u64,
47 /// The script which should be used in the transaction output.
48 output_script: Script,
49 /// The value passed in to ChannelManager::create_channel
52 /// Used to indicate that the client may now broadcast the funding transaction it created for a
53 /// channel. Broadcasting such a transaction prior to this event may lead to our counterparty
54 /// trivially stealing all funds in the funding transaction!
55 FundingBroadcastSafe {
56 /// The output, which was passed to ChannelManager::funding_transaction_generated, which is
57 /// now safe to broadcast.
58 funding_txo: OutPoint,
59 /// The value passed in to ChannelManager::create_channel
62 /// Indicates we've received money! Just gotta dig out that payment preimage and feed it to
63 /// ChannelManager::claim_funds to get it....
64 /// Note that if the preimage is not known or the amount paid is incorrect, you should call
65 /// ChannelManager::fail_htlc_backwards to free up resources for this HTLC and avoid
66 /// network congestion.
67 /// The amount paid should be considered 'incorrect' when it is less than or more than twice
68 /// the amount expected.
69 /// If you fail to call either ChannelManager::claim_funds or
70 /// ChannelManager::fail_htlc_backwards within the HTLC's timeout, the HTLC will be
71 /// automatically failed.
73 /// The hash for which the preimage should be handed to the ChannelManager.
74 payment_hash: PaymentHash,
75 /// The "payment secret". This authenticates the sender to the recipient, preventing a
76 /// number of deanonymization attacks during the routing process.
77 /// As nodes upgrade, the invoices you provide should likely migrate to setting the
78 /// payment_secret feature to required, at which point you should fail_backwards any HTLCs
79 /// which have a None here.
80 /// Until then, however, values of None should be ignored, and only incorrect Some values
81 /// should result in an HTLC fail_backwards.
82 /// Note that, in any case, this value must be passed as-is to any fail or claim calls as
83 /// the HTLC index includes this value.
84 payment_secret: Option<PaymentSecret>,
85 /// The value, in thousandths of a satoshi, that this payment is for. Note that you must
86 /// compare this to the expected value before accepting the payment (as otherwise you are
87 /// providing proof-of-payment for less than the value you expected!).
90 /// Indicates an outbound payment we made succeeded (ie it made it all the way to its target
91 /// and we got back the payment preimage for it).
92 /// Note that duplicative PaymentSent Events may be generated - it is your responsibility to
93 /// deduplicate them by payment_preimage (which MUST be unique)!
95 /// The preimage to the hash given to ChannelManager::send_payment.
96 /// Note that this serves as a payment receipt, if you wish to have such a thing, you must
98 payment_preimage: PaymentPreimage,
100 /// Indicates an outbound payment we made failed. Probably some intermediary node dropped
101 /// something. You may wish to retry with a different route.
102 /// Note that duplicative PaymentFailed Events may be generated - it is your responsibility to
103 /// deduplicate them by payment_hash (which MUST be unique)!
105 /// The hash which was given to ChannelManager::send_payment.
106 payment_hash: PaymentHash,
107 /// Indicates the payment was rejected for some reason by the recipient. This implies that
108 /// the payment has failed, not just the route in question. If this is not set, you may
109 /// retry the payment via a different route.
110 rejected_by_dest: bool,
112 error_code: Option<u16>,
114 error_data: Option<Vec<u8>>,
116 /// Used to indicate that ChannelManager::process_pending_htlc_forwards should be called at a
117 /// time in the future.
118 PendingHTLCsForwardable {
119 /// The minimum amount of time that should be waited prior to calling
120 /// process_pending_htlc_forwards. To increase the effort required to correlate payments,
121 /// you should wait a random amount of time in roughly the range (now + time_forwardable,
122 /// now + 5*time_forwardable).
123 time_forwardable: Duration,
125 /// Used to indicate that an output was generated on-chain which you should know how to spend.
126 /// Such an output will *not* ever be spent by rust-lightning, and are not at risk of your
127 /// counterparty spending them due to some kind of timeout. Thus, you need to store them
128 /// somewhere and spend them when you create on-chain transactions.
130 /// The outputs which you should store as spendable by you.
131 outputs: Vec<SpendableOutputDescriptor>,
135 impl Writeable for Event {
136 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
138 &Event::FundingGenerationReady { .. } => {
140 // We never write out FundingGenerationReady events as, upon disconnection, peers
141 // drop any channels which have not yet exchanged funding_signed.
143 &Event::FundingBroadcastSafe { ref funding_txo, ref user_channel_id } => {
145 funding_txo.write(writer)?;
146 user_channel_id.write(writer)?;
148 &Event::PaymentReceived { ref payment_hash, ref payment_secret, ref amt } => {
150 payment_hash.write(writer)?;
151 payment_secret.write(writer)?;
154 &Event::PaymentSent { ref payment_preimage } => {
156 payment_preimage.write(writer)?;
158 &Event::PaymentFailed { ref payment_hash, ref rejected_by_dest,
165 payment_hash.write(writer)?;
166 rejected_by_dest.write(writer)?;
168 error_code.write(writer)?;
170 error_data.write(writer)?;
172 &Event::PendingHTLCsForwardable { time_forwardable: _ } => {
174 // We don't write the time_fordwardable out at all, as we presume when the user
175 // deserializes us at least that much time has elapsed.
177 &Event::SpendableOutputs { ref outputs } => {
179 (outputs.len() as u64).write(writer)?;
180 for output in outputs.iter() {
181 output.write(writer)?;
188 impl MaybeReadable for Event {
189 fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Option<Self>, msgs::DecodeError> {
190 match Readable::read(reader)? {
192 1u8 => Ok(Some(Event::FundingBroadcastSafe {
193 funding_txo: Readable::read(reader)?,
194 user_channel_id: Readable::read(reader)?,
196 2u8 => Ok(Some(Event::PaymentReceived {
197 payment_hash: Readable::read(reader)?,
198 payment_secret: Readable::read(reader)?,
199 amt: Readable::read(reader)?,
201 3u8 => Ok(Some(Event::PaymentSent {
202 payment_preimage: Readable::read(reader)?,
204 4u8 => Ok(Some(Event::PaymentFailed {
205 payment_hash: Readable::read(reader)?,
206 rejected_by_dest: Readable::read(reader)?,
208 error_code: Readable::read(reader)?,
210 error_data: Readable::read(reader)?,
212 5u8 => Ok(Some(Event::PendingHTLCsForwardable {
213 time_forwardable: Duration::from_secs(0)
216 let outputs_len: u64 = Readable::read(reader)?;
217 let mut outputs = Vec::new();
218 for _ in 0..outputs_len {
219 outputs.push(Readable::read(reader)?);
221 Ok(Some(Event::SpendableOutputs { outputs }))
223 _ => Err(msgs::DecodeError::InvalidValue)
228 /// An event generated by ChannelManager which indicates a message should be sent to a peer (or
229 /// broadcast to most peers).
230 /// These events are handled by PeerManager::process_events if you are using a PeerManager.
232 pub enum MessageSendEvent {
233 /// Used to indicate that we've accepted a channel open and should send the accept_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::AcceptChannel,
241 /// Used to indicate that we've initiated a channel open and should send the open_channel
242 /// message provided to the given peer.
244 /// The node_id of the node which should receive this message
246 /// The message which should be sent.
247 msg: msgs::OpenChannel,
249 /// Used to indicate that a funding_created message should be sent to the peer with the given node_id.
251 /// The node_id of the node which should receive this message
253 /// The message which should be sent.
254 msg: msgs::FundingCreated,
256 /// Used to indicate that a funding_signed message should be sent to the peer with the given node_id.
258 /// The node_id of the node which should receive this message
260 /// The message which should be sent.
261 msg: msgs::FundingSigned,
263 /// Used to indicate that a funding_locked message should be sent to the peer with the given node_id.
265 /// The node_id of the node which should receive these message(s)
267 /// The funding_locked message which should be sent.
268 msg: msgs::FundingLocked,
270 /// Used to indicate that an announcement_signatures message should be sent to the peer with the given node_id.
271 SendAnnouncementSignatures {
272 /// The node_id of the node which should receive these message(s)
274 /// The announcement_signatures message which should be sent.
275 msg: msgs::AnnouncementSignatures,
277 /// Used to indicate that a series of HTLC update messages, as well as a commitment_signed
278 /// message should be sent to the peer with the given node_id.
280 /// The node_id of the node which should receive these message(s)
282 /// The update messages which should be sent. ALL messages in the struct should be sent!
283 updates: msgs::CommitmentUpdate,
285 /// Used to indicate that a revoke_and_ack message should be sent to the peer with the given node_id.
287 /// The node_id of the node which should receive this message
289 /// The message which should be sent.
290 msg: msgs::RevokeAndACK,
292 /// Used to indicate that a closing_signed message should be sent to the peer with the given node_id.
294 /// The node_id of the node which should receive this message
296 /// The message which should be sent.
297 msg: msgs::ClosingSigned,
299 /// Used to indicate that a shutdown message should be sent to the peer with the given node_id.
301 /// The node_id of the node which should receive this message
303 /// The message which should be sent.
306 /// Used to indicate that a channel_reestablish message should be sent to the peer with the given node_id.
307 SendChannelReestablish {
308 /// The node_id of the node which should receive this message
310 /// The message which should be sent.
311 msg: msgs::ChannelReestablish,
313 /// Used to indicate that a channel_announcement and channel_update should be broadcast to all
314 /// peers (except the peer with node_id either msg.contents.node_id_1 or msg.contents.node_id_2).
316 /// Note that after doing so, you very likely (unless you did so very recently) want to call
317 /// ChannelManager::broadcast_node_announcement to trigger a BroadcastNodeAnnouncement event.
318 /// This ensures that any nodes which see our channel_announcement also have a relevant
319 /// node_announcement, including relevant feature flags which may be important for routing
320 /// through or to us.
321 BroadcastChannelAnnouncement {
322 /// The channel_announcement which should be sent.
323 msg: msgs::ChannelAnnouncement,
324 /// The followup channel_update which should be sent.
325 update_msg: msgs::ChannelUpdate,
327 /// Used to indicate that a node_announcement should be broadcast to all peers.
328 BroadcastNodeAnnouncement {
329 /// The node_announcement which should be sent.
330 msg: msgs::NodeAnnouncement,
332 /// Used to indicate that a channel_update should be broadcast to all peers.
333 BroadcastChannelUpdate {
334 /// The channel_update which should be sent.
335 msg: msgs::ChannelUpdate,
337 /// Broadcast an error downstream to be handled
339 /// The node_id of the node which should receive this message
341 /// The action which should be taken.
342 action: msgs::ErrorAction
344 /// When a payment fails we may receive updates back from the hop where it failed. In such
345 /// cases this event is generated so that we can inform the network graph of this information.
346 PaymentFailureNetworkUpdate {
347 /// The channel/node update which should be sent to NetGraphMsgHandler
348 update: msgs::HTLCFailChannelUpdate,
350 /// Query a peer for channels with funding transaction UTXOs in a block range.
351 SendChannelRangeQuery {
352 /// The node_id of this message recipient
354 /// The query_channel_range which should be sent.
355 msg: msgs::QueryChannelRange,
357 /// Request routing gossip messages from a peer for a list of channels identified by
358 /// their short_channel_ids.
360 /// The node_id of this message recipient
362 /// The query_short_channel_ids which should be sent.
363 msg: msgs::QueryShortChannelIds,
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>;