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 /// As nodes upgrade, the invoices you provide should likely migrate to setting the
67 /// payment_secret feature to required, at which point you should fail_backwards any HTLCs
68 /// which have a None here.
69 /// Until then, however, values of None should be ignored, and only incorrect Some values
70 /// should result in an HTLC fail_backwards.
71 /// Note that, in any case, this value must be passed as-is to any fail or claim calls as
72 /// the HTLC index includes this value.
73 payment_secret: Option<PaymentSecret>,
74 /// The value, in thousandths of a satoshi, that this payment is for. Note that you must
75 /// compare this to the expected value before accepting the payment (as otherwise you are
76 /// providing proof-of-payment for less than the value you expected!).
78 /// This is the `user_payment_id` which was provided to
79 /// [`ChannelManager::create_inbound_payment_for_hash`] or
80 /// [`ChannelManager::create_inbound_payment`]. It has no meaning inside of LDK and is
81 /// simply copied here. It may be used to correlate PaymentReceived events with invoice
82 /// metadata stored elsewhere.
84 /// [`ChannelManager::create_inbound_payment`]: crate::ln::channelmanager::ChannelManager::create_inbound_payment
85 /// [`ChannelManager::create_inbound_payment_for_hash`]: crate::ln::channelmanager::ChannelManager::create_inbound_payment_for_hash
88 /// Indicates an outbound payment we made succeeded (ie it made it all the way to its target
89 /// and we got back the payment preimage for it).
90 /// Note that duplicative PaymentSent Events may be generated - it is your responsibility to
91 /// deduplicate them by payment_preimage (which MUST be unique)!
93 /// The preimage to the hash given to ChannelManager::send_payment.
94 /// Note that this serves as a payment receipt, if you wish to have such a thing, you must
96 payment_preimage: PaymentPreimage,
98 /// Indicates an outbound payment we made failed. Probably some intermediary node dropped
99 /// something. You may wish to retry with a different route.
100 /// Note that duplicative PaymentFailed Events may be generated - it is your responsibility to
101 /// deduplicate them by payment_hash (which MUST be unique)!
103 /// The hash which was given to ChannelManager::send_payment.
104 payment_hash: PaymentHash,
105 /// Indicates the payment was rejected for some reason by the recipient. This implies that
106 /// the payment has failed, not just the route in question. If this is not set, you may
107 /// retry the payment via a different route.
108 rejected_by_dest: bool,
110 error_code: Option<u16>,
112 error_data: Option<Vec<u8>>,
114 /// Used to indicate that ChannelManager::process_pending_htlc_forwards should be called at a
115 /// time in the future.
116 PendingHTLCsForwardable {
117 /// The minimum amount of time that should be waited prior to calling
118 /// process_pending_htlc_forwards. To increase the effort required to correlate payments,
119 /// you should wait a random amount of time in roughly the range (now + time_forwardable,
120 /// now + 5*time_forwardable).
121 time_forwardable: Duration,
123 /// Used to indicate that an output was generated on-chain which you should know how to spend.
124 /// Such an output will *not* ever be spent by rust-lightning, and are not at risk of your
125 /// counterparty spending them due to some kind of timeout. Thus, you need to store them
126 /// somewhere and spend them when you create on-chain transactions.
128 /// The outputs which you should store as spendable by you.
129 outputs: Vec<SpendableOutputDescriptor>,
133 impl Writeable for Event {
134 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
136 &Event::FundingGenerationReady { .. } => {
138 // We never write out FundingGenerationReady events as, upon disconnection, peers
139 // drop any channels which have not yet exchanged funding_signed.
141 &Event::PaymentReceived { ref payment_hash, ref payment_secret, ref amt, ref user_payment_id } => {
143 payment_hash.write(writer)?;
144 payment_secret.write(writer)?;
146 user_payment_id.write(writer)?;
148 &Event::PaymentSent { ref payment_preimage } => {
150 payment_preimage.write(writer)?;
152 &Event::PaymentFailed { ref payment_hash, ref rejected_by_dest,
159 payment_hash.write(writer)?;
160 rejected_by_dest.write(writer)?;
162 error_code.write(writer)?;
164 error_data.write(writer)?;
166 &Event::PendingHTLCsForwardable { time_forwardable: _ } => {
168 // We don't write the time_fordwardable out at all, as we presume when the user
169 // deserializes us at least that much time has elapsed.
171 &Event::SpendableOutputs { ref outputs } => {
173 (outputs.len() as u64).write(writer)?;
174 for output in outputs.iter() {
175 output.write(writer)?;
182 impl MaybeReadable for Event {
183 fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Option<Self>, msgs::DecodeError> {
184 match Readable::read(reader)? {
186 1u8 => Ok(Some(Event::PaymentReceived {
187 payment_hash: Readable::read(reader)?,
188 payment_secret: Readable::read(reader)?,
189 amt: Readable::read(reader)?,
190 user_payment_id: Readable::read(reader)?,
192 2u8 => Ok(Some(Event::PaymentSent {
193 payment_preimage: Readable::read(reader)?,
195 3u8 => Ok(Some(Event::PaymentFailed {
196 payment_hash: Readable::read(reader)?,
197 rejected_by_dest: Readable::read(reader)?,
199 error_code: Readable::read(reader)?,
201 error_data: Readable::read(reader)?,
203 4u8 => Ok(Some(Event::PendingHTLCsForwardable {
204 time_forwardable: Duration::from_secs(0)
207 let outputs_len: u64 = Readable::read(reader)?;
208 let mut outputs = Vec::new();
209 for _ in 0..outputs_len {
210 outputs.push(Readable::read(reader)?);
212 Ok(Some(Event::SpendableOutputs { outputs }))
214 _ => Err(msgs::DecodeError::InvalidValue)
219 /// An event generated by ChannelManager which indicates a message should be sent to a peer (or
220 /// broadcast to most peers).
221 /// These events are handled by PeerManager::process_events if you are using a PeerManager.
222 #[derive(Clone, Debug)]
223 pub enum MessageSendEvent {
224 /// Used to indicate that we've accepted a channel open and should send the accept_channel
225 /// message provided to the given peer.
227 /// The node_id of the node which should receive this message
229 /// The message which should be sent.
230 msg: msgs::AcceptChannel,
232 /// Used to indicate that we've initiated a channel open and should send the open_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::OpenChannel,
240 /// Used to indicate that a funding_created message should be sent to the peer with the given node_id.
242 /// The node_id of the node which should receive this message
244 /// The message which should be sent.
245 msg: msgs::FundingCreated,
247 /// Used to indicate that a funding_signed message should be sent to the peer with the given node_id.
249 /// The node_id of the node which should receive this message
251 /// The message which should be sent.
252 msg: msgs::FundingSigned,
254 /// Used to indicate that a funding_locked message should be sent to the peer with the given node_id.
256 /// The node_id of the node which should receive these message(s)
258 /// The funding_locked message which should be sent.
259 msg: msgs::FundingLocked,
261 /// Used to indicate that an announcement_signatures message should be sent to the peer with the given node_id.
262 SendAnnouncementSignatures {
263 /// The node_id of the node which should receive these message(s)
265 /// The announcement_signatures message which should be sent.
266 msg: msgs::AnnouncementSignatures,
268 /// Used to indicate that a series of HTLC update messages, as well as a commitment_signed
269 /// message should be sent to the peer with the given node_id.
271 /// The node_id of the node which should receive these message(s)
273 /// The update messages which should be sent. ALL messages in the struct should be sent!
274 updates: msgs::CommitmentUpdate,
276 /// Used to indicate that a revoke_and_ack message should be sent to the peer with the given node_id.
278 /// The node_id of the node which should receive this message
280 /// The message which should be sent.
281 msg: msgs::RevokeAndACK,
283 /// Used to indicate that a closing_signed message should be sent to the peer with the given node_id.
285 /// The node_id of the node which should receive this message
287 /// The message which should be sent.
288 msg: msgs::ClosingSigned,
290 /// Used to indicate that a shutdown message should be sent to the peer with the given node_id.
292 /// The node_id of the node which should receive this message
294 /// The message which should be sent.
297 /// Used to indicate that a channel_reestablish message should be sent to the peer with the given node_id.
298 SendChannelReestablish {
299 /// The node_id of the node which should receive this message
301 /// The message which should be sent.
302 msg: msgs::ChannelReestablish,
304 /// Used to indicate that a channel_announcement and channel_update should be broadcast to all
305 /// peers (except the peer with node_id either msg.contents.node_id_1 or msg.contents.node_id_2).
307 /// Note that after doing so, you very likely (unless you did so very recently) want to call
308 /// ChannelManager::broadcast_node_announcement to trigger a BroadcastNodeAnnouncement event.
309 /// This ensures that any nodes which see our channel_announcement also have a relevant
310 /// node_announcement, including relevant feature flags which may be important for routing
311 /// through or to us.
312 BroadcastChannelAnnouncement {
313 /// The channel_announcement which should be sent.
314 msg: msgs::ChannelAnnouncement,
315 /// The followup channel_update which should be sent.
316 update_msg: msgs::ChannelUpdate,
318 /// Used to indicate that a node_announcement should be broadcast to all peers.
319 BroadcastNodeAnnouncement {
320 /// The node_announcement which should be sent.
321 msg: msgs::NodeAnnouncement,
323 /// Used to indicate that a channel_update should be broadcast to all peers.
324 BroadcastChannelUpdate {
325 /// The channel_update which should be sent.
326 msg: msgs::ChannelUpdate,
328 /// Broadcast an error downstream to be handled
330 /// The node_id of the node which should receive this message
332 /// The action which should be taken.
333 action: msgs::ErrorAction
335 /// When a payment fails we may receive updates back from the hop where it failed. In such
336 /// cases this event is generated so that we can inform the network graph of this information.
337 PaymentFailureNetworkUpdate {
338 /// The channel/node update which should be sent to NetGraphMsgHandler
339 update: msgs::HTLCFailChannelUpdate,
341 /// Query a peer for channels with funding transaction UTXOs in a block range.
342 SendChannelRangeQuery {
343 /// The node_id of this message recipient
345 /// The query_channel_range which should be sent.
346 msg: msgs::QueryChannelRange,
348 /// Request routing gossip messages from a peer for a list of channels identified by
349 /// their short_channel_ids.
351 /// The node_id of this message recipient
353 /// The query_short_channel_ids which should be sent.
354 msg: msgs::QueryShortChannelIds,
356 /// Sends a reply to a channel range query. This may be one of several SendReplyChannelRange events
357 /// emitted during processing of the query.
358 SendReplyChannelRange {
359 /// The node_id of this message recipient
361 /// The reply_channel_range which should be sent.
362 msg: msgs::ReplyChannelRange,
366 /// A trait indicating an object may generate message send events
367 pub trait MessageSendEventsProvider {
368 /// Gets the list of pending events which were generated by previous actions, clearing the list
370 fn get_and_clear_pending_msg_events(&self) -> Vec<MessageSendEvent>;
373 /// A trait indicating an object may generate events
374 pub trait EventsProvider {
375 /// Gets the list of pending events which were generated by previous actions, clearing the list
377 fn get_and_clear_pending_events(&self) -> Vec<Event>;