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).
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 /// Used to indicate that the client may now broadcast the funding transaction it created for a
52 /// channel. Broadcasting such a transaction prior to this event may lead to our counterparty
53 /// trivially stealing all funds in the funding transaction!
54 FundingBroadcastSafe {
55 /// The output, which was passed to ChannelManager::funding_transaction_generated, which is
56 /// now safe to broadcast.
57 funding_txo: OutPoint,
58 /// The value passed in to ChannelManager::create_channel
61 /// Indicates we've received money! Just gotta dig out that payment preimage and feed it to
62 /// ChannelManager::claim_funds to get it....
63 /// Note that if the preimage is not known or the amount paid is incorrect, you should call
64 /// ChannelManager::fail_htlc_backwards to free up resources for this HTLC and avoid
65 /// network congestion.
66 /// The amount paid should be considered 'incorrect' when it is less than or more than twice
67 /// the amount expected.
68 /// If you fail to call either ChannelManager::claim_funds or
69 /// ChannelManager::fail_htlc_backwards within the HTLC's timeout, the HTLC will be
70 /// automatically failed.
72 /// The hash for which the preimage should be handed to the ChannelManager.
73 payment_hash: PaymentHash,
74 /// The "payment secret". This authenticates the sender to the recipient, preventing a
75 /// number of deanonymization attacks during the routing process.
76 /// As nodes upgrade, the invoices you provide should likely migrate to setting the
77 /// payment_secret feature to required, at which point you should fail_backwards any HTLCs
78 /// which have a None here.
79 /// Until then, however, values of None should be ignored, and only incorrect Some values
80 /// should result in an HTLC fail_backwards.
81 /// Note that, in any case, this value must be passed as-is to any fail or claim calls as
82 /// the HTLC index includes this value.
83 payment_secret: Option<PaymentSecret>,
84 /// The value, in thousandths of a satoshi, that this payment is for. Note that you must
85 /// compare this to the expected value before accepting the payment (as otherwise you are
86 /// providing proof-of-payment for less than the value you expected!).
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::FundingBroadcastSafe { ref funding_txo, ref user_channel_id } => {
144 funding_txo.write(writer)?;
145 user_channel_id.write(writer)?;
147 &Event::PaymentReceived { ref payment_hash, ref payment_secret, ref amt } => {
149 payment_hash.write(writer)?;
150 payment_secret.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::FundingBroadcastSafe {
192 funding_txo: Readable::read(reader)?,
193 user_channel_id: Readable::read(reader)?,
195 2u8 => Ok(Some(Event::PaymentReceived {
196 payment_hash: Readable::read(reader)?,
197 payment_secret: Readable::read(reader)?,
198 amt: Readable::read(reader)?,
200 3u8 => Ok(Some(Event::PaymentSent {
201 payment_preimage: Readable::read(reader)?,
203 4u8 => Ok(Some(Event::PaymentFailed {
204 payment_hash: Readable::read(reader)?,
205 rejected_by_dest: Readable::read(reader)?,
207 error_code: Readable::read(reader)?,
209 error_data: Readable::read(reader)?,
211 5u8 => Ok(Some(Event::PendingHTLCsForwardable {
212 time_forwardable: Duration::from_secs(0)
215 let outputs_len: u64 = Readable::read(reader)?;
216 let mut outputs = Vec::new();
217 for _ in 0..outputs_len {
218 outputs.push(Readable::read(reader)?);
220 Ok(Some(Event::SpendableOutputs { outputs }))
222 _ => Err(msgs::DecodeError::InvalidValue)
227 /// An event generated by ChannelManager which indicates a message should be sent to a peer (or
228 /// broadcast to most peers).
229 /// These events are handled by PeerManager::process_events if you are using a PeerManager.
231 pub enum MessageSendEvent {
232 /// Used to indicate that we've accepted a channel open and should send the accept_channel
233 /// message provided to the given peer.
235 /// The node_id of the node which should receive this message
237 /// The message which should be sent.
238 msg: msgs::AcceptChannel,
240 /// Used to indicate that we've initiated a channel open and should send the open_channel
241 /// message provided to the given peer.
243 /// The node_id of the node which should receive this message
245 /// The message which should be sent.
246 msg: msgs::OpenChannel,
248 /// Used to indicate that a funding_created 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::FundingCreated,
255 /// Used to indicate that a funding_signed message should be sent to the peer with the given node_id.
257 /// The node_id of the node which should receive this message
259 /// The message which should be sent.
260 msg: msgs::FundingSigned,
262 /// Used to indicate that a funding_locked message should be sent to the peer with the given node_id.
264 /// The node_id of the node which should receive these message(s)
266 /// The funding_locked message which should be sent.
267 msg: msgs::FundingLocked,
269 /// Used to indicate that an announcement_signatures message should be sent to the peer with the given node_id.
270 SendAnnouncementSignatures {
271 /// The node_id of the node which should receive these message(s)
273 /// The announcement_signatures message which should be sent.
274 msg: msgs::AnnouncementSignatures,
276 /// Used to indicate that a series of HTLC update messages, as well as a commitment_signed
277 /// message should be sent to the peer with the given node_id.
279 /// The node_id of the node which should receive these message(s)
281 /// The update messages which should be sent. ALL messages in the struct should be sent!
282 updates: msgs::CommitmentUpdate,
284 /// Used to indicate that a revoke_and_ack 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::RevokeAndACK,
291 /// Used to indicate that a closing_signed 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.
296 msg: msgs::ClosingSigned,
298 /// Used to indicate that a shutdown message should be sent to the peer with the given node_id.
300 /// The node_id of the node which should receive this message
302 /// The message which should be sent.
305 /// Used to indicate that a channel_reestablish message should be sent to the peer with the given node_id.
306 SendChannelReestablish {
307 /// The node_id of the node which should receive this message
309 /// The message which should be sent.
310 msg: msgs::ChannelReestablish,
312 /// Used to indicate that a channel_announcement and channel_update should be broadcast to all
313 /// peers (except the peer with node_id either msg.contents.node_id_1 or msg.contents.node_id_2).
315 /// Note that after doing so, you very likely (unless you did so very recently) want to call
316 /// ChannelManager::broadcast_node_announcement to trigger a BroadcastNodeAnnouncement event.
317 /// This ensures that any nodes which see our channel_announcement also have a relevant
318 /// node_announcement, including relevant feature flags which may be important for routing
319 /// through or to us.
320 BroadcastChannelAnnouncement {
321 /// The channel_announcement which should be sent.
322 msg: msgs::ChannelAnnouncement,
323 /// The followup channel_update which should be sent.
324 update_msg: msgs::ChannelUpdate,
326 /// Used to indicate that a node_announcement should be broadcast to all peers.
327 BroadcastNodeAnnouncement {
328 /// The node_announcement which should be sent.
329 msg: msgs::NodeAnnouncement,
331 /// Used to indicate that a channel_update should be broadcast to all peers.
332 BroadcastChannelUpdate {
333 /// The channel_update which should be sent.
334 msg: msgs::ChannelUpdate,
336 /// Broadcast an error downstream to be handled
338 /// The node_id of the node which should receive this message
340 /// The action which should be taken.
341 action: msgs::ErrorAction
343 /// When a payment fails we may receive updates back from the hop where it failed. In such
344 /// cases this event is generated so that we can inform the network graph of this information.
345 PaymentFailureNetworkUpdate {
346 /// The channel/node update which should be sent to NetGraphMsgHandler
347 update: msgs::HTLCFailChannelUpdate,
351 /// A trait indicating an object may generate message send events
352 pub trait MessageSendEventsProvider {
353 /// Gets the list of pending events which were generated by previous actions, clearing the list
355 fn get_and_clear_pending_msg_events(&self) -> Vec<MessageSendEvent>;
358 /// A trait indicating an object may generate events
359 pub trait EventsProvider {
360 /// Gets the list of pending events which were generated by previous actions, clearing the list
362 fn get_and_clear_pending_events(&self) -> Vec<Event>;