_ Git - rust-lightning/blob - lightning/src/events/mod.rs

   1 // This file is Copyright its original authors, visible in version control
   2 // history.
   3 //
   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
   8 // licenses.
   9
  10 //! Events are returned from various bits in the library which indicate some action must be taken
  11 //! by the client.
  12 //!
  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
  15 //! few other things.
  16
  17 pub mod bump_transaction;
  18
  19 pub use bump_transaction::BumpTransactionEvent;
  20
  21 use crate::sign::SpendableOutputDescriptor;
  22 use crate::ln::channelmanager::{InterceptId, PaymentId, RecipientOnionFields};
  23 use crate::ln::channel::FUNDING_CONF_DEADLINE_BLOCKS;
  24 use crate::ln::features::ChannelTypeFeatures;
  25 use crate::ln::msgs;
  26 use crate::ln::{PaymentPreimage, PaymentHash, PaymentSecret};
  27 use crate::routing::gossip::NetworkUpdate;
  28 use crate::util::errors::APIError;
  29 use crate::util::ser::{BigSize, FixedLengthReader, Writeable, Writer, MaybeReadable, Readable, RequiredWrapper, UpgradableRequired, WithoutLength};
  30 use crate::util::string::UntrustedString;
  31 use crate::routing::router::{BlindedTail, Path, RouteHop, RouteParameters};
  32
  33 use bitcoin::{PackedLockTime, Transaction, OutPoint};
  34 use bitcoin::blockdata::script::Script;
  35 use bitcoin::hashes::Hash;
  36 use bitcoin::hashes::sha256::Hash as Sha256;
  37 use bitcoin::secp256k1::PublicKey;
  38 use crate::io;
  39 use crate::prelude::*;
  40 use core::time::Duration;
  41 use core::ops::Deref;
  42 use crate::sync::Arc;
  43
  44 /// Some information provided on receipt of payment depends on whether the payment received is a
  45 /// spontaneous payment or a "conventional" lightning payment that's paying an invoice.
  46 #[derive(Clone, Debug, PartialEq, Eq)]
  47 pub enum PaymentPurpose {
  48         /// Information for receiving a payment that we generated an invoice for.
  49         InvoicePayment {
  50                 /// The preimage to the payment_hash, if the payment hash (and secret) were fetched via
  51                 /// [`ChannelManager::create_inbound_payment`]. If provided, this can be handed directly to
  52                 /// [`ChannelManager::claim_funds`].
  53                 ///
  54                 /// [`ChannelManager::create_inbound_payment`]: crate::ln::channelmanager::ChannelManager::create_inbound_payment
  55                 /// [`ChannelManager::claim_funds`]: crate::ln::channelmanager::ChannelManager::claim_funds
  56                 payment_preimage: Option<PaymentPreimage>,
  57                 /// The "payment secret". This authenticates the sender to the recipient, preventing a
  58                 /// number of deanonymization attacks during the routing process.
  59                 /// It is provided here for your reference, however its accuracy is enforced directly by
  60                 /// [`ChannelManager`] using the values you previously provided to
  61                 /// [`ChannelManager::create_inbound_payment`] or
  62                 /// [`ChannelManager::create_inbound_payment_for_hash`].
  63                 ///
  64                 /// [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
  65                 /// [`ChannelManager::create_inbound_payment`]: crate::ln::channelmanager::ChannelManager::create_inbound_payment
  66                 /// [`ChannelManager::create_inbound_payment_for_hash`]: crate::ln::channelmanager::ChannelManager::create_inbound_payment_for_hash
  67                 payment_secret: PaymentSecret,
  68         },
  69         /// Because this is a spontaneous payment, the payer generated their own preimage rather than us
  70         /// (the payee) providing a preimage.
  71         SpontaneousPayment(PaymentPreimage),
  72 }
  73
  74 impl_writeable_tlv_based_enum!(PaymentPurpose,
  75         (0, InvoicePayment) => {
  76                 (0, payment_preimage, option),
  77                 (2, payment_secret, required),
  78         };
  79         (2, SpontaneousPayment)
  80 );
  81
  82 /// When the payment path failure took place and extra details about it. [`PathFailure::OnPath`] may
  83 /// contain a [`NetworkUpdate`] that needs to be applied to the [`NetworkGraph`].
  84 ///
  85 /// [`NetworkUpdate`]: crate::routing::gossip::NetworkUpdate
  86 /// [`NetworkGraph`]: crate::routing::gossip::NetworkGraph
  87 #[derive(Clone, Debug, Eq, PartialEq)]
  88 pub enum PathFailure {
  89         /// We failed to initially send the payment and no HTLC was committed to. Contains the relevant
  90         /// error.
  91         InitialSend {
  92                 /// The error surfaced from initial send.
  93                 err: APIError,
  94         },
  95         /// A hop on the path failed to forward our payment.
  96         OnPath {
  97                 /// If present, this [`NetworkUpdate`] should be applied to the [`NetworkGraph`] so that routing
  98                 /// decisions can take into account the update.
  99                 ///
 100                 /// [`NetworkUpdate`]: crate::routing::gossip::NetworkUpdate
 101                 /// [`NetworkGraph`]: crate::routing::gossip::NetworkGraph
 102                 network_update: Option<NetworkUpdate>,
 103         },
 104 }
 105
 106 impl_writeable_tlv_based_enum_upgradable!(PathFailure,
 107         (0, OnPath) => {
 108                 (0, network_update, upgradable_option),
 109         },
 110         (2, InitialSend) => {
 111                 (0, err, upgradable_required),
 112         },
 113 );
 114
 115 #[derive(Clone, Debug, PartialEq, Eq)]
 116 /// The reason the channel was closed. See individual variants for more details.
 117 pub enum ClosureReason {
 118         /// Closure generated from receiving a peer error message.
 119         ///
 120         /// Our counterparty may have broadcasted their latest commitment state, and we have
 121         /// as well.
 122         CounterpartyForceClosed {
 123                 /// The error which the peer sent us.
 124                 ///
 125                 /// Be careful about printing the peer_msg, a well-crafted message could exploit
 126                 /// a security vulnerability in the terminal emulator or the logging subsystem.
 127                 /// To be safe, use `Display` on `UntrustedString`
 128                 ///
 129                 /// [`UntrustedString`]: crate::util::string::UntrustedString
 130                 peer_msg: UntrustedString,
 131         },
 132         /// Closure generated from [`ChannelManager::force_close_channel`], called by the user.
 133         ///
 134         /// [`ChannelManager::force_close_channel`]: crate::ln::channelmanager::ChannelManager::force_close_channel.
 135         HolderForceClosed,
 136         /// The channel was closed after negotiating a cooperative close and we've now broadcasted
 137         /// the cooperative close transaction. Note the shutdown may have been initiated by us.
 138         //TODO: split between CounterpartyInitiated/LocallyInitiated
 139         CooperativeClosure,
 140         /// A commitment transaction was confirmed on chain, closing the channel. Most likely this
 141         /// commitment transaction came from our counterparty, but it may also have come from
 142         /// a copy of our own `ChannelMonitor`.
 143         CommitmentTxConfirmed,
 144         /// The funding transaction failed to confirm in a timely manner on an inbound channel.
 145         FundingTimedOut,
 146         /// Closure generated from processing an event, likely a HTLC forward/relay/reception.
 147         ProcessingError {
 148                 /// A developer-readable error message which we generated.
 149                 err: String,
 150         },
 151         /// The peer disconnected prior to funding completing. In this case the spec mandates that we
 152         /// forget the channel entirely - we can attempt again if the peer reconnects.
 153         ///
 154         /// This includes cases where we restarted prior to funding completion, including prior to the
 155         /// initial [`ChannelMonitor`] persistence completing.
 156         ///
 157         /// In LDK versions prior to 0.0.107 this could also occur if we were unable to connect to the
 158         /// peer because of mutual incompatibility between us and our channel counterparty.
 159         ///
 160         /// [`ChannelMonitor`]: crate::chain::channelmonitor::ChannelMonitor
 161         DisconnectedPeer,
 162         /// Closure generated from `ChannelManager::read` if the [`ChannelMonitor`] is newer than
 163         /// the [`ChannelManager`] deserialized.
 164         ///
 165         /// [`ChannelMonitor`]: crate::chain::channelmonitor::ChannelMonitor
 166         /// [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
 167         OutdatedChannelManager,
 168         /// The counterparty requested a cooperative close of a channel that had not been funded yet.
 169         /// The channel has been immediately closed.
 170         CounterpartyCoopClosedUnfundedChannel,
 171 }
 172
 173 impl core::fmt::Display for ClosureReason {
 174         fn fmt(&self, f: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {
 175                 f.write_str("Channel closed because ")?;
 176                 match self {
 177                         ClosureReason::CounterpartyForceClosed { peer_msg } => {
 178                                 f.write_fmt(format_args!("counterparty force-closed with message: {}", peer_msg))
 179                         },
 180                         ClosureReason::HolderForceClosed => f.write_str("user manually force-closed the channel"),
 181                         ClosureReason::CooperativeClosure => f.write_str("the channel was cooperatively closed"),
 182                         ClosureReason::CommitmentTxConfirmed => f.write_str("commitment or closing transaction was confirmed on chain."),
 183                         ClosureReason::FundingTimedOut => write!(f, "funding transaction failed to confirm within {} blocks", FUNDING_CONF_DEADLINE_BLOCKS),
 184                         ClosureReason::ProcessingError { err } => {
 185                                 f.write_str("of an exception: ")?;
 186                                 f.write_str(&err)
 187                         },
 188                         ClosureReason::DisconnectedPeer => f.write_str("the peer disconnected prior to the channel being funded"),
 189                         ClosureReason::OutdatedChannelManager => f.write_str("the ChannelManager read from disk was stale compared to ChannelMonitor(s)"),
 190                         ClosureReason::CounterpartyCoopClosedUnfundedChannel => f.write_str("the peer requested the unfunded channel be closed"),
 191                 }
 192         }
 193 }
 194
 195 impl_writeable_tlv_based_enum_upgradable!(ClosureReason,
 196         (0, CounterpartyForceClosed) => { (1, peer_msg, required) },
 197         (1, FundingTimedOut) => {},
 198         (2, HolderForceClosed) => {},
 199         (6, CommitmentTxConfirmed) => {},
 200         (4, CooperativeClosure) => {},
 201         (8, ProcessingError) => { (1, err, required) },
 202         (10, DisconnectedPeer) => {},
 203         (12, OutdatedChannelManager) => {},
 204         (13, CounterpartyCoopClosedUnfundedChannel) => {},
 205 );
 206
 207 /// Intended destination of a failed HTLC as indicated in [`Event::HTLCHandlingFailed`].
 208 #[derive(Clone, Debug, PartialEq, Eq)]
 209 pub enum HTLCDestination {
 210         /// We tried forwarding to a channel but failed to do so. An example of such an instance is when
 211         /// there is insufficient capacity in our outbound channel.
 212         NextHopChannel {
 213                 /// The `node_id` of the next node. For backwards compatibility, this field is
 214                 /// marked as optional, versions prior to 0.0.110 may not always be able to provide
 215                 /// counterparty node information.
 216                 node_id: Option<PublicKey>,
 217                 /// The outgoing `channel_id` between us and the next node.
 218                 channel_id: [u8; 32],
 219         },
 220         /// Scenario where we are unsure of the next node to forward the HTLC to.
 221         UnknownNextHop {
 222                 /// Short channel id we are requesting to forward an HTLC to.
 223                 requested_forward_scid: u64,
 224         },
 225         /// We couldn't forward to the outgoing scid. An example would be attempting to send a duplicate
 226         /// intercept HTLC.
 227         InvalidForward {
 228                 /// Short channel id we are requesting to forward an HTLC to.
 229                 requested_forward_scid: u64
 230         },
 231         /// Failure scenario where an HTLC may have been forwarded to be intended for us,
 232         /// but is invalid for some reason, so we reject it.
 233         ///
 234         /// Some of the reasons may include:
 235         /// * HTLC Timeouts
 236         /// * Excess HTLCs for a payment that we have already fully received, over-paying for the
 237         ///   payment,
 238         /// * The counterparty node modified the HTLC in transit,
 239         /// * A probing attack where an intermediary node is trying to detect if we are the ultimate
 240         ///   recipient for a payment.
 241         FailedPayment {
 242                 /// The payment hash of the payment we attempted to process.
 243                 payment_hash: PaymentHash
 244         },
 245 }
 246
 247 impl_writeable_tlv_based_enum_upgradable!(HTLCDestination,
 248         (0, NextHopChannel) => {
 249                 (0, node_id, required),
 250                 (2, channel_id, required),
 251         },
 252         (1, InvalidForward) => {
 253                 (0, requested_forward_scid, required),
 254         },
 255         (2, UnknownNextHop) => {
 256                 (0, requested_forward_scid, required),
 257         },
 258         (4, FailedPayment) => {
 259                 (0, payment_hash, required),
 260         },
 261 );
 262
 263 /// Will be used in [`Event::HTLCIntercepted`] to identify the next hop in the HTLC's path.
 264 /// Currently only used in serialization for the sake of maintaining compatibility. More variants
 265 /// will be added for general-purpose HTLC forward intercepts as well as trampoline forward
 266 /// intercepts in upcoming work.
 267 enum InterceptNextHop {
 268         FakeScid {
 269                 requested_next_hop_scid: u64,
 270         },
 271 }
 272
 273 impl_writeable_tlv_based_enum!(InterceptNextHop,
 274         (0, FakeScid) => {
 275                 (0, requested_next_hop_scid, required),
 276         };
 277 );
 278
 279 /// The reason the payment failed. Used in [`Event::PaymentFailed`].
 280 #[derive(Clone, Copy, Debug, PartialEq, Eq)]
 281 pub enum PaymentFailureReason {
 282         /// The intended recipient rejected our payment.
 283         RecipientRejected,
 284         /// The user chose to abandon this payment by calling [`ChannelManager::abandon_payment`].
 285         ///
 286         /// [`ChannelManager::abandon_payment`]: crate::ln::channelmanager::ChannelManager::abandon_payment
 287         UserAbandoned,
 288         /// We exhausted all of our retry attempts while trying to send the payment, or we
 289         /// exhausted the [`Retry::Timeout`] if the user set one. If at any point a retry
 290         /// attempt failed while being forwarded along the path, an [`Event::PaymentPathFailed`] will
 291         /// have come before this.
 292         ///
 293         /// [`Retry::Timeout`]: crate::ln::channelmanager::Retry::Timeout
 294         RetriesExhausted,
 295         /// The payment expired while retrying, based on the provided
 296         /// [`PaymentParameters::expiry_time`].
 297         ///
 298         /// [`PaymentParameters::expiry_time`]: crate::routing::router::PaymentParameters::expiry_time
 299         PaymentExpired,
 300         /// We failed to find a route while retrying the payment.
 301         RouteNotFound,
 302         /// This error should generally never happen. This likely means that there is a problem with
 303         /// your router.
 304         UnexpectedError,
 305 }
 306
 307 impl_writeable_tlv_based_enum!(PaymentFailureReason,
 308         (0, RecipientRejected) => {},
 309         (2, UserAbandoned) => {},
 310         (4, RetriesExhausted) => {},
 311         (6, PaymentExpired) => {},
 312         (8, RouteNotFound) => {},
 313         (10, UnexpectedError) => {}, ;
 314 );
 315
 316 /// An Event which you should probably take some action in response to.
 317 ///
 318 /// Note that while Writeable and Readable are implemented for Event, you probably shouldn't use
 319 /// them directly as they don't round-trip exactly (for example FundingGenerationReady is never
 320 /// written as it makes no sense to respond to it after reconnecting to peers).
 321 #[derive(Clone, Debug, PartialEq, Eq)]
 322 pub enum Event {
 323         /// Used to indicate that the client should generate a funding transaction with the given
 324         /// parameters and then call [`ChannelManager::funding_transaction_generated`].
 325         /// Generated in [`ChannelManager`] message handling.
 326         /// Note that *all inputs* in the funding transaction must spend SegWit outputs or your
 327         /// counterparty can steal your funds!
 328         ///
 329         /// [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
 330         /// [`ChannelManager::funding_transaction_generated`]: crate::ln::channelmanager::ChannelManager::funding_transaction_generated
 331         FundingGenerationReady {
 332                 /// The random channel_id we picked which you'll need to pass into
 333                 /// [`ChannelManager::funding_transaction_generated`].
 334                 ///
 335                 /// [`ChannelManager::funding_transaction_generated`]: crate::ln::channelmanager::ChannelManager::funding_transaction_generated
 336                 temporary_channel_id: [u8; 32],
 337                 /// The counterparty's node_id, which you'll need to pass back into
 338                 /// [`ChannelManager::funding_transaction_generated`].
 339                 ///
 340                 /// [`ChannelManager::funding_transaction_generated`]: crate::ln::channelmanager::ChannelManager::funding_transaction_generated
 341                 counterparty_node_id: PublicKey,
 342                 /// The value, in satoshis, that the output should have.
 343                 channel_value_satoshis: u64,
 344                 /// The script which should be used in the transaction output.
 345                 output_script: Script,
 346                 /// The `user_channel_id` value passed in to [`ChannelManager::create_channel`] for outbound
 347                 /// channels, or to [`ChannelManager::accept_inbound_channel`] for inbound channels if
 348                 /// [`UserConfig::manually_accept_inbound_channels`] config flag is set to true. Otherwise
 349                 /// `user_channel_id` will be randomized for an inbound channel.  This may be zero for objects
 350                 /// serialized with LDK versions prior to 0.0.113.
 351                 ///
 352                 /// [`ChannelManager::create_channel`]: crate::ln::channelmanager::ChannelManager::create_channel
 353                 /// [`ChannelManager::accept_inbound_channel`]: crate::ln::channelmanager::ChannelManager::accept_inbound_channel
 354                 /// [`UserConfig::manually_accept_inbound_channels`]: crate::util::config::UserConfig::manually_accept_inbound_channels
 355                 user_channel_id: u128,
 356         },
 357         /// Indicates that we've been offered a payment and it needs to be claimed via calling
 358         /// [`ChannelManager::claim_funds`] with the preimage given in [`PaymentPurpose`].
 359         ///
 360         /// Note that if the preimage is not known, you should call
 361         /// [`ChannelManager::fail_htlc_backwards`] or [`ChannelManager::fail_htlc_backwards_with_reason`]
 362         /// to free up resources for this HTLC and avoid network congestion.
 363         ///
 364         /// If [`Event::PaymentClaimable::onion_fields`] is `Some`, and includes custom TLVs with even type
 365         /// numbers, you should use [`ChannelManager::fail_htlc_backwards_with_reason`] with
 366         /// [`FailureCode::InvalidOnionPayload`] if you fail to understand and handle the contents, or
 367         /// [`ChannelManager::claim_funds_with_known_custom_tlvs`] upon successful handling.
 368         /// If you don't intend to check for custom TLVs, you can simply use
 369         /// [`ChannelManager::claim_funds`], which will automatically fail back even custom TLVs.
 370         ///
 371         /// If you fail to call [`ChannelManager::claim_funds`],
 372         /// [`ChannelManager::claim_funds_with_known_custom_tlvs`],
 373         /// [`ChannelManager::fail_htlc_backwards`], or
 374         /// [`ChannelManager::fail_htlc_backwards_with_reason`] within the HTLC's timeout, the HTLC will
 375         /// be automatically failed.
 376         ///
 377         /// # Note
 378         /// LDK will not stop an inbound payment from being paid multiple times, so multiple
 379         /// `PaymentClaimable` events may be generated for the same payment. In such a case it is
 380         /// polite (and required in the lightning specification) to fail the payment the second time
 381         /// and give the sender their money back rather than accepting double payment.
 382         ///
 383         /// # Note
 384         /// This event used to be called `PaymentReceived` in LDK versions 0.0.112 and earlier.
 385         ///
 386         /// [`ChannelManager::claim_funds`]: crate::ln::channelmanager::ChannelManager::claim_funds
 387         /// [`ChannelManager::claim_funds_with_known_custom_tlvs`]: crate::ln::channelmanager::ChannelManager::claim_funds_with_known_custom_tlvs
 388         /// [`FailureCode::InvalidOnionPayload`]: crate::ln::channelmanager::FailureCode::InvalidOnionPayload
 389         /// [`ChannelManager::fail_htlc_backwards`]: crate::ln::channelmanager::ChannelManager::fail_htlc_backwards
 390         /// [`ChannelManager::fail_htlc_backwards_with_reason`]: crate::ln::channelmanager::ChannelManager::fail_htlc_backwards_with_reason
 391         PaymentClaimable {
 392                 /// The node that will receive the payment after it has been claimed.
 393                 /// This is useful to identify payments received via [phantom nodes].
 394                 /// This field will always be filled in when the event was generated by LDK versions
 395                 /// 0.0.113 and above.
 396                 ///
 397                 /// [phantom nodes]: crate::sign::PhantomKeysManager
 398                 receiver_node_id: Option<PublicKey>,
 399                 /// The hash for which the preimage should be handed to the ChannelManager. Note that LDK will
 400                 /// not stop you from registering duplicate payment hashes for inbound payments.
 401                 payment_hash: PaymentHash,
 402                 /// The fields in the onion which were received with each HTLC. Only fields which were
 403                 /// identical in each HTLC involved in the payment will be included here.
 404                 ///
 405                 /// Payments received on LDK versions prior to 0.0.115 will have this field unset.
 406                 onion_fields: Option<RecipientOnionFields>,
 407                 /// The value, in thousandths of a satoshi, that this payment is claimable for. May be greater
 408                 /// than the invoice amount.
 409                 ///
 410                 /// May be less than the invoice amount if [`ChannelConfig::accept_underpaying_htlcs`] is set
 411                 /// and the previous hop took an extra fee.
 412                 ///
 413                 /// # Note
 414                 /// If [`ChannelConfig::accept_underpaying_htlcs`] is set and you claim without verifying this
 415                 /// field, you may lose money!
 416                 ///
 417                 /// [`ChannelConfig::accept_underpaying_htlcs`]: crate::util::config::ChannelConfig::accept_underpaying_htlcs
 418                 amount_msat: u64,
 419                 /// The value, in thousands of a satoshi, that was skimmed off of this payment as an extra fee
 420                 /// taken by our channel counterparty.
 421                 ///
 422                 /// Will always be 0 unless [`ChannelConfig::accept_underpaying_htlcs`] is set.
 423                 ///
 424                 /// [`ChannelConfig::accept_underpaying_htlcs`]: crate::util::config::ChannelConfig::accept_underpaying_htlcs
 425                 counterparty_skimmed_fee_msat: u64,
 426                 /// Information for claiming this received payment, based on whether the purpose of the
 427                 /// payment is to pay an invoice or to send a spontaneous payment.
 428                 purpose: PaymentPurpose,
 429                 /// The `channel_id` indicating over which channel we received the payment.
 430                 via_channel_id: Option<[u8; 32]>,
 431                 /// The `user_channel_id` indicating over which channel we received the payment.
 432                 via_user_channel_id: Option<u128>,
 433                 /// The block height at which this payment will be failed back and will no longer be
 434                 /// eligible for claiming.
 435                 ///
 436                 /// Prior to this height, a call to [`ChannelManager::claim_funds`] is guaranteed to
 437                 /// succeed, however you should wait for [`Event::PaymentClaimed`] to be sure.
 438                 ///
 439                 /// [`ChannelManager::claim_funds`]: crate::ln::channelmanager::ChannelManager::claim_funds
 440                 claim_deadline: Option<u32>,
 441         },
 442         /// Indicates a payment has been claimed and we've received money!
 443         ///
 444         /// This most likely occurs when [`ChannelManager::claim_funds`] has been called in response
 445         /// to an [`Event::PaymentClaimable`]. However, if we previously crashed during a
 446         /// [`ChannelManager::claim_funds`] call you may see this event without a corresponding
 447         /// [`Event::PaymentClaimable`] event.
 448         ///
 449         /// # Note
 450         /// LDK will not stop an inbound payment from being paid multiple times, so multiple
 451         /// `PaymentClaimable` events may be generated for the same payment. If you then call
 452         /// [`ChannelManager::claim_funds`] twice for the same [`Event::PaymentClaimable`] you may get
 453         /// multiple `PaymentClaimed` events.
 454         ///
 455         /// [`ChannelManager::claim_funds`]: crate::ln::channelmanager::ChannelManager::claim_funds
 456         PaymentClaimed {
 457                 /// The node that received the payment.
 458                 /// This is useful to identify payments which were received via [phantom nodes].
 459                 /// This field will always be filled in when the event was generated by LDK versions
 460                 /// 0.0.113 and above.
 461                 ///
 462                 /// [phantom nodes]: crate::sign::PhantomKeysManager
 463                 receiver_node_id: Option<PublicKey>,
 464                 /// The payment hash of the claimed payment. Note that LDK will not stop you from
 465                 /// registering duplicate payment hashes for inbound payments.
 466                 payment_hash: PaymentHash,
 467                 /// The value, in thousandths of a satoshi, that this payment is for. May be greater than the
 468                 /// invoice amount.
 469                 amount_msat: u64,
 470                 /// The purpose of the claimed payment, i.e. whether the payment was for an invoice or a
 471                 /// spontaneous payment.
 472                 purpose: PaymentPurpose,
 473         },
 474         /// Indicates an outbound payment we made succeeded (i.e. it made it all the way to its target
 475         /// and we got back the payment preimage for it).
 476         ///
 477         /// Note for MPP payments: in rare cases, this event may be preceded by a `PaymentPathFailed`
 478         /// event. In this situation, you SHOULD treat this payment as having succeeded.
 479         PaymentSent {
 480                 /// The `payment_id` passed to [`ChannelManager::send_payment`].
 481                 ///
 482                 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
 483                 payment_id: Option<PaymentId>,
 484                 /// The preimage to the hash given to ChannelManager::send_payment.
 485                 /// Note that this serves as a payment receipt, if you wish to have such a thing, you must
 486                 /// store it somehow!
 487                 payment_preimage: PaymentPreimage,
 488                 /// The hash that was given to [`ChannelManager::send_payment`].
 489                 ///
 490                 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
 491                 payment_hash: PaymentHash,
 492                 /// The total fee which was spent at intermediate hops in this payment, across all paths.
 493                 ///
 494                 /// Note that, like [`Route::get_total_fees`] this does *not* include any potential
 495                 /// overpayment to the recipient node.
 496                 ///
 497                 /// If the recipient or an intermediate node misbehaves and gives us free money, this may
 498                 /// overstate the amount paid, though this is unlikely.
 499                 ///
 500                 /// [`Route::get_total_fees`]: crate::routing::router::Route::get_total_fees
 501                 fee_paid_msat: Option<u64>,
 502         },
 503         /// Indicates an outbound payment failed. Individual [`Event::PaymentPathFailed`] events
 504         /// provide failure information for each path attempt in the payment, including retries.
 505         ///
 506         /// This event is provided once there are no further pending HTLCs for the payment and the
 507         /// payment is no longer retryable, due either to the [`Retry`] provided or
 508         /// [`ChannelManager::abandon_payment`] having been called for the corresponding payment.
 509         ///
 510         /// [`Retry`]: crate::ln::channelmanager::Retry
 511         /// [`ChannelManager::abandon_payment`]: crate::ln::channelmanager::ChannelManager::abandon_payment
 512         PaymentFailed {
 513                 /// The `payment_id` passed to [`ChannelManager::send_payment`].
 514                 ///
 515                 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
 516                 payment_id: PaymentId,
 517                 /// The hash that was given to [`ChannelManager::send_payment`].
 518                 ///
 519                 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
 520                 payment_hash: PaymentHash,
 521                 /// The reason the payment failed. This is only `None` for events generated or serialized
 522                 /// by versions prior to 0.0.115.
 523                 reason: Option<PaymentFailureReason>,
 524         },
 525         /// Indicates that a path for an outbound payment was successful.
 526         ///
 527         /// Always generated after [`Event::PaymentSent`] and thus useful for scoring channels. See
 528         /// [`Event::PaymentSent`] for obtaining the payment preimage.
 529         PaymentPathSuccessful {
 530                 /// The `payment_id` passed to [`ChannelManager::send_payment`].
 531                 ///
 532                 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
 533                 payment_id: PaymentId,
 534                 /// The hash that was given to [`ChannelManager::send_payment`].
 535                 ///
 536                 /// This will be `Some` for all payments which completed on LDK 0.0.104 or later.
 537                 ///
 538                 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
 539                 payment_hash: Option<PaymentHash>,
 540                 /// The payment path that was successful.
 541                 ///
 542                 /// May contain a closed channel if the HTLC sent along the path was fulfilled on chain.
 543                 path: Path,
 544         },
 545         /// Indicates an outbound HTLC we sent failed, likely due to an intermediary node being unable to
 546         /// handle the HTLC.
 547         ///
 548         /// Note that this does *not* indicate that all paths for an MPP payment have failed, see
 549         /// [`Event::PaymentFailed`].
 550         ///
 551         /// See [`ChannelManager::abandon_payment`] for giving up on this payment before its retries have
 552         /// been exhausted.
 553         ///
 554         /// [`ChannelManager::abandon_payment`]: crate::ln::channelmanager::ChannelManager::abandon_payment
 555         PaymentPathFailed {
 556                 /// The `payment_id` passed to [`ChannelManager::send_payment`].
 557                 ///
 558                 /// This will be `Some` for all payment paths which failed on LDK 0.0.103 or later.
 559                 ///
 560                 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
 561                 /// [`ChannelManager::abandon_payment`]: crate::ln::channelmanager::ChannelManager::abandon_payment
 562                 payment_id: Option<PaymentId>,
 563                 /// The hash that was given to [`ChannelManager::send_payment`].
 564                 ///
 565                 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
 566                 payment_hash: PaymentHash,
 567                 /// Indicates the payment was rejected for some reason by the recipient. This implies that
 568                 /// the payment has failed, not just the route in question. If this is not set, the payment may
 569                 /// be retried via a different route.
 570                 payment_failed_permanently: bool,
 571                 /// Extra error details based on the failure type. May contain an update that needs to be
 572                 /// applied to the [`NetworkGraph`].
 573                 ///
 574                 /// [`NetworkGraph`]: crate::routing::gossip::NetworkGraph
 575                 failure: PathFailure,
 576                 /// The payment path that failed.
 577                 path: Path,
 578                 /// The channel responsible for the failed payment path.
 579                 ///
 580                 /// Note that for route hints or for the first hop in a path this may be an SCID alias and
 581                 /// may not refer to a channel in the public network graph. These aliases may also collide
 582                 /// with channels in the public network graph.
 583                 ///
 584                 /// If this is `Some`, then the corresponding channel should be avoided when the payment is
 585                 /// retried. May be `None` for older [`Event`] serializations.
 586                 short_channel_id: Option<u64>,
 587 #[cfg(test)]
 588                 error_code: Option<u16>,
 589 #[cfg(test)]
 590                 error_data: Option<Vec<u8>>,
 591         },
 592         /// Indicates that a probe payment we sent returned successful, i.e., only failed at the destination.
 593         ProbeSuccessful {
 594                 /// The id returned by [`ChannelManager::send_probe`].
 595                 ///
 596                 /// [`ChannelManager::send_probe`]: crate::ln::channelmanager::ChannelManager::send_probe
 597                 payment_id: PaymentId,
 598                 /// The hash generated by [`ChannelManager::send_probe`].
 599                 ///
 600                 /// [`ChannelManager::send_probe`]: crate::ln::channelmanager::ChannelManager::send_probe
 601                 payment_hash: PaymentHash,
 602                 /// The payment path that was successful.
 603                 path: Path,
 604         },
 605         /// Indicates that a probe payment we sent failed at an intermediary node on the path.
 606         ProbeFailed {
 607                 /// The id returned by [`ChannelManager::send_probe`].
 608                 ///
 609                 /// [`ChannelManager::send_probe`]: crate::ln::channelmanager::ChannelManager::send_probe
 610                 payment_id: PaymentId,
 611                 /// The hash generated by [`ChannelManager::send_probe`].
 612                 ///
 613                 /// [`ChannelManager::send_probe`]: crate::ln::channelmanager::ChannelManager::send_probe
 614                 payment_hash: PaymentHash,
 615                 /// The payment path that failed.
 616                 path: Path,
 617                 /// The channel responsible for the failed probe.
 618                 ///
 619                 /// Note that for route hints or for the first hop in a path this may be an SCID alias and
 620                 /// may not refer to a channel in the public network graph. These aliases may also collide
 621                 /// with channels in the public network graph.
 622                 short_channel_id: Option<u64>,
 623         },
 624         /// Used to indicate that [`ChannelManager::process_pending_htlc_forwards`] should be called at
 625         /// a time in the future.
 626         ///
 627         /// [`ChannelManager::process_pending_htlc_forwards`]: crate::ln::channelmanager::ChannelManager::process_pending_htlc_forwards
 628         PendingHTLCsForwardable {
 629                 /// The minimum amount of time that should be waited prior to calling
 630                 /// process_pending_htlc_forwards. To increase the effort required to correlate payments,
 631                 /// you should wait a random amount of time in roughly the range (now + time_forwardable,
 632                 /// now + 5*time_forwardable).
 633                 time_forwardable: Duration,
 634         },
 635         /// Used to indicate that we've intercepted an HTLC forward. This event will only be generated if
 636         /// you've encoded an intercept scid in the receiver's invoice route hints using
 637         /// [`ChannelManager::get_intercept_scid`] and have set [`UserConfig::accept_intercept_htlcs`].
 638         ///
 639         /// [`ChannelManager::forward_intercepted_htlc`] or
 640         /// [`ChannelManager::fail_intercepted_htlc`] MUST be called in response to this event. See
 641         /// their docs for more information.
 642         ///
 643         /// [`ChannelManager::get_intercept_scid`]: crate::ln::channelmanager::ChannelManager::get_intercept_scid
 644         /// [`UserConfig::accept_intercept_htlcs`]: crate::util::config::UserConfig::accept_intercept_htlcs
 645         /// [`ChannelManager::forward_intercepted_htlc`]: crate::ln::channelmanager::ChannelManager::forward_intercepted_htlc
 646         /// [`ChannelManager::fail_intercepted_htlc`]: crate::ln::channelmanager::ChannelManager::fail_intercepted_htlc
 647         HTLCIntercepted {
 648                 /// An id to help LDK identify which HTLC is being forwarded or failed.
 649                 intercept_id: InterceptId,
 650                 /// The fake scid that was programmed as the next hop's scid, generated using
 651                 /// [`ChannelManager::get_intercept_scid`].
 652                 ///
 653                 /// [`ChannelManager::get_intercept_scid`]: crate::ln::channelmanager::ChannelManager::get_intercept_scid
 654                 requested_next_hop_scid: u64,
 655                 /// The payment hash used for this HTLC.
 656                 payment_hash: PaymentHash,
 657                 /// How many msats were received on the inbound edge of this HTLC.
 658                 inbound_amount_msat: u64,
 659                 /// How many msats the payer intended to route to the next node. Depending on the reason you are
 660                 /// intercepting this payment, you might take a fee by forwarding less than this amount.
 661                 /// Forwarding less than this amount may break compatibility with LDK versions prior to 0.0.116.
 662                 ///
 663                 /// Note that LDK will NOT check that expected fees were factored into this value. You MUST
 664                 /// check that whatever fee you want has been included here or subtract it as required. Further,
 665                 /// LDK will not stop you from forwarding more than you received.
 666                 expected_outbound_amount_msat: u64,
 667         },
 668         /// Used to indicate that an output which you should know how to spend was confirmed on chain
 669         /// and is now spendable.
 670         /// Such an output will *not* ever be spent by rust-lightning, and are not at risk of your
 671         /// counterparty spending them due to some kind of timeout. Thus, you need to store them
 672         /// somewhere and spend them when you create on-chain transactions.
 673         SpendableOutputs {
 674                 /// The outputs which you should store as spendable by you.
 675                 outputs: Vec<SpendableOutputDescriptor>,
 676                 /// The `channel_id` indicating which channel the spendable outputs belong to.
 677                 ///
 678                 /// This will always be `Some` for events generated by LDK versions 0.0.117 and above.
 679                 channel_id: Option<[u8; 32]>,
 680         },
 681         /// This event is generated when a payment has been successfully forwarded through us and a
 682         /// forwarding fee earned.
 683         PaymentForwarded {
 684                 /// The incoming channel between the previous node and us. This is only `None` for events
 685                 /// generated or serialized by versions prior to 0.0.107.
 686                 prev_channel_id: Option<[u8; 32]>,
 687                 /// The outgoing channel between the next node and us. This is only `None` for events
 688                 /// generated or serialized by versions prior to 0.0.107.
 689                 next_channel_id: Option<[u8; 32]>,
 690                 /// The fee, in milli-satoshis, which was earned as a result of the payment.
 691                 ///
 692                 /// Note that if we force-closed the channel over which we forwarded an HTLC while the HTLC
 693                 /// was pending, the amount the next hop claimed will have been rounded down to the nearest
 694                 /// whole satoshi. Thus, the fee calculated here may be higher than expected as we still
 695                 /// claimed the full value in millisatoshis from the source. In this case,
 696                 /// `claim_from_onchain_tx` will be set.
 697                 ///
 698                 /// If the channel which sent us the payment has been force-closed, we will claim the funds
 699                 /// via an on-chain transaction. In that case we do not yet know the on-chain transaction
 700                 /// fees which we will spend and will instead set this to `None`. It is possible duplicate
 701                 /// `PaymentForwarded` events are generated for the same payment iff `fee_earned_msat` is
 702                 /// `None`.
 703                 fee_earned_msat: Option<u64>,
 704                 /// If this is `true`, the forwarded HTLC was claimed by our counterparty via an on-chain
 705                 /// transaction.
 706                 claim_from_onchain_tx: bool,
 707                 /// The final amount forwarded, in milli-satoshis, after the fee is deducted.
 708                 ///
 709                 /// The caveat described above the `fee_earned_msat` field applies here as well.
 710                 outbound_amount_forwarded_msat: Option<u64>,
 711         },
 712         /// Used to indicate that a channel with the given `channel_id` is being opened and pending
 713         /// confirmation on-chain.
 714         ///
 715         /// This event is emitted when the funding transaction has been signed and is broadcast to the
 716         /// network. For 0conf channels it will be immediately followed by the corresponding
 717         /// [`Event::ChannelReady`] event.
 718         ChannelPending {
 719                 /// The `channel_id` of the channel that is pending confirmation.
 720                 channel_id: [u8; 32],
 721                 /// The `user_channel_id` value passed in to [`ChannelManager::create_channel`] for outbound
 722                 /// channels, or to [`ChannelManager::accept_inbound_channel`] for inbound channels if
 723                 /// [`UserConfig::manually_accept_inbound_channels`] config flag is set to true. Otherwise
 724                 /// `user_channel_id` will be randomized for an inbound channel.
 725                 ///
 726                 /// [`ChannelManager::create_channel`]: crate::ln::channelmanager::ChannelManager::create_channel
 727                 /// [`ChannelManager::accept_inbound_channel`]: crate::ln::channelmanager::ChannelManager::accept_inbound_channel
 728                 /// [`UserConfig::manually_accept_inbound_channels`]: crate::util::config::UserConfig::manually_accept_inbound_channels
 729                 user_channel_id: u128,
 730                 /// The `temporary_channel_id` this channel used to be known by during channel establishment.
 731                 ///
 732                 /// Will be `None` for channels created prior to LDK version 0.0.115.
 733                 former_temporary_channel_id: Option<[u8; 32]>,
 734                 /// The `node_id` of the channel counterparty.
 735                 counterparty_node_id: PublicKey,
 736                 /// The outpoint of the channel's funding transaction.
 737                 funding_txo: OutPoint,
 738         },
 739         /// Used to indicate that a channel with the given `channel_id` is ready to
 740         /// be used. This event is emitted either when the funding transaction has been confirmed
 741         /// on-chain, or, in case of a 0conf channel, when both parties have confirmed the channel
 742         /// establishment.
 743         ChannelReady {
 744                 /// The `channel_id` of the channel that is ready.
 745                 channel_id: [u8; 32],
 746                 /// The `user_channel_id` value passed in to [`ChannelManager::create_channel`] for outbound
 747                 /// channels, or to [`ChannelManager::accept_inbound_channel`] for inbound channels if
 748                 /// [`UserConfig::manually_accept_inbound_channels`] config flag is set to true. Otherwise
 749                 /// `user_channel_id` will be randomized for an inbound channel.
 750                 ///
 751                 /// [`ChannelManager::create_channel`]: crate::ln::channelmanager::ChannelManager::create_channel
 752                 /// [`ChannelManager::accept_inbound_channel`]: crate::ln::channelmanager::ChannelManager::accept_inbound_channel
 753                 /// [`UserConfig::manually_accept_inbound_channels`]: crate::util::config::UserConfig::manually_accept_inbound_channels
 754                 user_channel_id: u128,
 755                 /// The `node_id` of the channel counterparty.
 756                 counterparty_node_id: PublicKey,
 757                 /// The features that this channel will operate with.
 758                 channel_type: ChannelTypeFeatures,
 759         },
 760         /// Used to indicate that a previously opened channel with the given `channel_id` is in the
 761         /// process of closure.
 762         ///
 763         /// Note that this event is only triggered for accepted channels: if the
 764         /// [`UserConfig::manually_accept_inbound_channels`] config flag is set to true and the channel is
 765         /// rejected, no `ChannelClosed` event will be sent.
 766         ///
 767         /// [`ChannelManager::accept_inbound_channel`]: crate::ln::channelmanager::ChannelManager::accept_inbound_channel
 768         /// [`UserConfig::manually_accept_inbound_channels`]: crate::util::config::UserConfig::manually_accept_inbound_channels
 769         ChannelClosed  {
 770                 /// The `channel_id` of the channel which has been closed. Note that on-chain transactions
 771                 /// resolving the channel are likely still awaiting confirmation.
 772                 channel_id: [u8; 32],
 773                 /// The `user_channel_id` value passed in to [`ChannelManager::create_channel`] for outbound
 774                 /// channels, or to [`ChannelManager::accept_inbound_channel`] for inbound channels if
 775                 /// [`UserConfig::manually_accept_inbound_channels`] config flag is set to true. Otherwise
 776                 /// `user_channel_id` will be randomized for inbound channels.
 777                 /// This may be zero for inbound channels serialized prior to 0.0.113 and will always be
 778                 /// zero for objects serialized with LDK versions prior to 0.0.102.
 779                 ///
 780                 /// [`ChannelManager::create_channel`]: crate::ln::channelmanager::ChannelManager::create_channel
 781                 /// [`ChannelManager::accept_inbound_channel`]: crate::ln::channelmanager::ChannelManager::accept_inbound_channel
 782                 /// [`UserConfig::manually_accept_inbound_channels`]: crate::util::config::UserConfig::manually_accept_inbound_channels
 783                 user_channel_id: u128,
 784                 /// The reason the channel was closed.
 785                 reason: ClosureReason,
 786                 /// Counterparty in the closed channel.
 787                 ///
 788                 /// This field will be `None` for objects serialized prior to LDK 0.0.117.
 789                 counterparty_node_id: Option<PublicKey>,
 790                 /// Channel capacity of the closing channel (sats).
 791                 ///
 792                 /// This field will be `None` for objects serialized prior to LDK 0.0.117.
 793                 channel_capacity_sats: Option<u64>,
 794         },
 795         /// Used to indicate to the user that they can abandon the funding transaction and recycle the
 796         /// inputs for another purpose.
 797         DiscardFunding {
 798                 /// The channel_id of the channel which has been closed.
 799                 channel_id: [u8; 32],
 800                 /// The full transaction received from the user
 801                 transaction: Transaction
 802         },
 803         /// Indicates a request to open a new channel by a peer.
 804         ///
 805         /// To accept the request, call [`ChannelManager::accept_inbound_channel`]. To reject the request,
 806         /// call [`ChannelManager::force_close_without_broadcasting_txn`]. Note that a ['ChannelClosed`]
 807         /// event will _not_ be triggered if the channel is rejected.
 808         ///
 809         /// The event is only triggered when a new open channel request is received and the
 810         /// [`UserConfig::manually_accept_inbound_channels`] config flag is set to true.
 811         ///
 812         /// [`ChannelManager::accept_inbound_channel`]: crate::ln::channelmanager::ChannelManager::accept_inbound_channel
 813         /// [`ChannelManager::force_close_without_broadcasting_txn`]: crate::ln::channelmanager::ChannelManager::force_close_without_broadcasting_txn
 814         /// [`UserConfig::manually_accept_inbound_channels`]: crate::util::config::UserConfig::manually_accept_inbound_channels
 815         OpenChannelRequest {
 816                 /// The temporary channel ID of the channel requested to be opened.
 817                 ///
 818                 /// When responding to the request, the `temporary_channel_id` should be passed
 819                 /// back to the ChannelManager through [`ChannelManager::accept_inbound_channel`] to accept,
 820                 /// or through [`ChannelManager::force_close_without_broadcasting_txn`] to reject.
 821                 ///
 822                 /// [`ChannelManager::accept_inbound_channel`]: crate::ln::channelmanager::ChannelManager::accept_inbound_channel
 823                 /// [`ChannelManager::force_close_without_broadcasting_txn`]: crate::ln::channelmanager::ChannelManager::force_close_without_broadcasting_txn
 824                 temporary_channel_id: [u8; 32],
 825                 /// The node_id of the counterparty requesting to open the channel.
 826                 ///
 827                 /// When responding to the request, the `counterparty_node_id` should be passed
 828                 /// back to the `ChannelManager` through [`ChannelManager::accept_inbound_channel`] to
 829                 /// accept the request, or through [`ChannelManager::force_close_without_broadcasting_txn`] to reject the
 830                 /// request.
 831                 ///
 832                 /// [`ChannelManager::accept_inbound_channel`]: crate::ln::channelmanager::ChannelManager::accept_inbound_channel
 833                 /// [`ChannelManager::force_close_without_broadcasting_txn`]: crate::ln::channelmanager::ChannelManager::force_close_without_broadcasting_txn
 834                 counterparty_node_id: PublicKey,
 835                 /// The channel value of the requested channel.
 836                 funding_satoshis: u64,
 837                 /// Our starting balance in the channel if the request is accepted, in milli-satoshi.
 838                 push_msat: u64,
 839                 /// The features that this channel will operate with. If you reject the channel, a
 840                 /// well-behaved counterparty may automatically re-attempt the channel with a new set of
 841                 /// feature flags.
 842                 ///
 843                 /// Note that if [`ChannelTypeFeatures::supports_scid_privacy`] returns true on this type,
 844                 /// the resulting [`ChannelManager`] will not be readable by versions of LDK prior to
 845                 /// 0.0.106.
 846                 ///
 847                 /// Furthermore, note that if [`ChannelTypeFeatures::supports_zero_conf`] returns true on this type,
 848                 /// the resulting [`ChannelManager`] will not be readable by versions of LDK prior to
 849                 /// 0.0.107. Channels setting this type also need to get manually accepted via
 850                 /// [`crate::ln::channelmanager::ChannelManager::accept_inbound_channel_from_trusted_peer_0conf`],
 851                 /// or will be rejected otherwise.
 852                 ///
 853                 /// [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
 854                 channel_type: ChannelTypeFeatures,
 855         },
 856         /// Indicates that the HTLC was accepted, but could not be processed when or after attempting to
 857         /// forward it.
 858         ///
 859         /// Some scenarios where this event may be sent include:
 860         /// * Insufficient capacity in the outbound channel
 861         /// * While waiting to forward the HTLC, the channel it is meant to be forwarded through closes
 862         /// * When an unknown SCID is requested for forwarding a payment.
 863         /// * Expected MPP amount has already been reached
 864         /// * The HTLC has timed out
 865         ///
 866         /// This event, however, does not get generated if an HTLC fails to meet the forwarding
 867         /// requirements (i.e. insufficient fees paid, or a CLTV that is too soon).
 868         HTLCHandlingFailed {
 869                 /// The channel over which the HTLC was received.
 870                 prev_channel_id: [u8; 32],
 871                 /// Destination of the HTLC that failed to be processed.
 872                 failed_next_destination: HTLCDestination,
 873         },
 874         /// Indicates that a transaction originating from LDK needs to have its fee bumped. This event
 875         /// requires confirmed external funds to be readily available to spend.
 876         ///
 877         /// LDK does not currently generate this event unless the
 878         /// [`ChannelHandshakeConfig::negotiate_anchors_zero_fee_htlc_tx`] config flag is set to true.
 879         /// It is limited to the scope of channels with anchor outputs.
 880         ///
 881         /// [`ChannelHandshakeConfig::negotiate_anchors_zero_fee_htlc_tx`]: crate::util::config::ChannelHandshakeConfig::negotiate_anchors_zero_fee_htlc_tx
 882         BumpTransaction(BumpTransactionEvent),
 883 }
 884
 885 impl Writeable for Event {
 886         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
 887                 match self {
 888                         &Event::FundingGenerationReady { .. } => {
 889                                 0u8.write(writer)?;
 890                                 // We never write out FundingGenerationReady events as, upon disconnection, peers
 891                                 // drop any channels which have not yet exchanged funding_signed.
 892                         },
 893                         &Event::PaymentClaimable { ref payment_hash, ref amount_msat, counterparty_skimmed_fee_msat,
 894                                 ref purpose, ref receiver_node_id, ref via_channel_id, ref via_user_channel_id,
 895                                 ref claim_deadline, ref onion_fields
 896                         } => {
 897                                 1u8.write(writer)?;
 898                                 let mut payment_secret = None;
 899                                 let payment_preimage;
 900                                 match &purpose {
 901                                         PaymentPurpose::InvoicePayment { payment_preimage: preimage, payment_secret: secret } => {
 902                                                 payment_secret = Some(secret);
 903                                                 payment_preimage = *preimage;
 904                                         },
 905                                         PaymentPurpose::SpontaneousPayment(preimage) => {
 906                                                 payment_preimage = Some(*preimage);
 907                                         }
 908                                 }
 909                                 let skimmed_fee_opt = if counterparty_skimmed_fee_msat == 0 { None }
 910                                         else { Some(counterparty_skimmed_fee_msat) };
 911                                 write_tlv_fields!(writer, {
 912                                         (0, payment_hash, required),
 913                                         (1, receiver_node_id, option),
 914                                         (2, payment_secret, option),
 915                                         (3, via_channel_id, option),
 916                                         (4, amount_msat, required),
 917                                         (5, via_user_channel_id, option),
 918                                         // Type 6 was `user_payment_id` on 0.0.103 and earlier
 919                                         (7, claim_deadline, option),
 920                                         (8, payment_preimage, option),
 921                                         (9, onion_fields, option),
 922                                         (10, skimmed_fee_opt, option),
 923                                 });
 924                         },
 925                         &Event::PaymentSent { ref payment_id, ref payment_preimage, ref payment_hash, ref fee_paid_msat } => {
 926                                 2u8.write(writer)?;
 927                                 write_tlv_fields!(writer, {
 928                                         (0, payment_preimage, required),
 929                                         (1, payment_hash, required),
 930                                         (3, payment_id, option),
 931                                         (5, fee_paid_msat, option),
 932                                 });
 933                         },
 934                         &Event::PaymentPathFailed {
 935                                 ref payment_id, ref payment_hash, ref payment_failed_permanently, ref failure,
 936                                 ref path, ref short_channel_id,
 937                                 #[cfg(test)]
 938                                 ref error_code,
 939                                 #[cfg(test)]
 940                                 ref error_data,
 941                         } => {
 942                                 3u8.write(writer)?;
 943                                 #[cfg(test)]
 944                                 error_code.write(writer)?;
 945                                 #[cfg(test)]
 946                                 error_data.write(writer)?;
 947                                 write_tlv_fields!(writer, {
 948                                         (0, payment_hash, required),
 949                                         (1, None::<NetworkUpdate>, option), // network_update in LDK versions prior to 0.0.114
 950                                         (2, payment_failed_permanently, required),
 951                                         (3, false, required), // all_paths_failed in LDK versions prior to 0.0.114
 952                                         (4, path.blinded_tail, option),
 953                                         (5, path.hops, required_vec),
 954                                         (7, short_channel_id, option),
 955                                         (9, None::<RouteParameters>, option), // retry in LDK versions prior to 0.0.115
 956                                         (11, payment_id, option),
 957                                         (13, failure, required),
 958                                 });
 959                         },
 960                         &Event::PendingHTLCsForwardable { time_forwardable: _ } => {
 961                                 4u8.write(writer)?;
 962                                 // Note that we now ignore these on the read end as we'll re-generate them in
 963                                 // ChannelManager, we write them here only for backwards compatibility.
 964                         },
 965                         &Event::SpendableOutputs { ref outputs, channel_id } => {
 966                                 5u8.write(writer)?;
 967                                 write_tlv_fields!(writer, {
 968                                         (0, WithoutLength(outputs), required),
 969                                         (1, channel_id, option),
 970                                 });
 971                         },
 972                         &Event::HTLCIntercepted { requested_next_hop_scid, payment_hash, inbound_amount_msat, expected_outbound_amount_msat, intercept_id } => {
 973                                 6u8.write(writer)?;
 974                                 let intercept_scid = InterceptNextHop::FakeScid { requested_next_hop_scid };
 975                                 write_tlv_fields!(writer, {
 976                                         (0, intercept_id, required),
 977                                         (2, intercept_scid, required),
 978                                         (4, payment_hash, required),
 979                                         (6, inbound_amount_msat, required),
 980                                         (8, expected_outbound_amount_msat, required),
 981                                 });
 982                         }
 983                         &Event::PaymentForwarded {
 984                                 fee_earned_msat, prev_channel_id, claim_from_onchain_tx,
 985                                 next_channel_id, outbound_amount_forwarded_msat
 986                         } => {
 987                                 7u8.write(writer)?;
 988                                 write_tlv_fields!(writer, {
 989                                         (0, fee_earned_msat, option),
 990                                         (1, prev_channel_id, option),
 991                                         (2, claim_from_onchain_tx, required),
 992                                         (3, next_channel_id, option),
 993                                         (5, outbound_amount_forwarded_msat, option),
 994                                 });
 995                         },
 996                         &Event::ChannelClosed { ref channel_id, ref user_channel_id, ref reason,
 997                                 ref counterparty_node_id, ref channel_capacity_sats
 998                         } => {
 999                                 9u8.write(writer)?;
1000                                 // `user_channel_id` used to be a single u64 value. In order to remain backwards
1001                                 // compatible with versions prior to 0.0.113, the u128 is serialized as two
1002                                 // separate u64 values.
1003                                 let user_channel_id_low = *user_channel_id as u64;
1004                                 let user_channel_id_high = (*user_channel_id >> 64) as u64;
1005                                 write_tlv_fields!(writer, {
1006                                         (0, channel_id, required),
1007                                         (1, user_channel_id_low, required),
1008                                         (2, reason, required),
1009                                         (3, user_channel_id_high, required),
1010                                         (5, counterparty_node_id, option),
1011                                         (7, channel_capacity_sats, option),
1012                                 });
1013                         },
1014                         &Event::DiscardFunding { ref channel_id, ref transaction } => {
1015                                 11u8.write(writer)?;
1016                                 write_tlv_fields!(writer, {
1017                                         (0, channel_id, required),
1018                                         (2, transaction, required)
1019                                 })
1020                         },
1021                         &Event::PaymentPathSuccessful { ref payment_id, ref payment_hash, ref path } => {
1022                                 13u8.write(writer)?;
1023                                 write_tlv_fields!(writer, {
1024                                         (0, payment_id, required),
1025                                         (2, payment_hash, option),
1026                                         (4, path.hops, required_vec),
1027                                         (6, path.blinded_tail, option),
1028                                 })
1029                         },
1030                         &Event::PaymentFailed { ref payment_id, ref payment_hash, ref reason } => {
1031                                 15u8.write(writer)?;
1032                                 write_tlv_fields!(writer, {
1033                                         (0, payment_id, required),
1034                                         (1, reason, option),
1035                                         (2, payment_hash, required),
1036                                 })
1037                         },
1038                         &Event::OpenChannelRequest { .. } => {
1039                                 17u8.write(writer)?;
1040                                 // We never write the OpenChannelRequest events as, upon disconnection, peers
1041                                 // drop any channels which have not yet exchanged funding_signed.
1042                         },
1043                         &Event::PaymentClaimed { ref payment_hash, ref amount_msat, ref purpose, ref receiver_node_id } => {
1044                                 19u8.write(writer)?;
1045                                 write_tlv_fields!(writer, {
1046                                         (0, payment_hash, required),
1047                                         (1, receiver_node_id, option),
1048                                         (2, purpose, required),
1049                                         (4, amount_msat, required),
1050                                 });
1051                         },
1052                         &Event::ProbeSuccessful { ref payment_id, ref payment_hash, ref path } => {
1053                                 21u8.write(writer)?;
1054                                 write_tlv_fields!(writer, {
1055                                         (0, payment_id, required),
1056                                         (2, payment_hash, required),
1057                                         (4, path.hops, required_vec),
1058                                         (6, path.blinded_tail, option),
1059                                 })
1060                         },
1061                         &Event::ProbeFailed { ref payment_id, ref payment_hash, ref path, ref short_channel_id } => {
1062                                 23u8.write(writer)?;
1063                                 write_tlv_fields!(writer, {
1064                                         (0, payment_id, required),
1065                                         (2, payment_hash, required),
1066                                         (4, path.hops, required_vec),
1067                                         (6, short_channel_id, option),
1068                                         (8, path.blinded_tail, option),
1069                                 })
1070                         },
1071                         &Event::HTLCHandlingFailed { ref prev_channel_id, ref failed_next_destination } => {
1072                                 25u8.write(writer)?;
1073                                 write_tlv_fields!(writer, {
1074                                         (0, prev_channel_id, required),
1075                                         (2, failed_next_destination, required),
1076                                 })
1077                         },
1078                         &Event::BumpTransaction(ref event)=> {
1079                                 27u8.write(writer)?;
1080                                 match event {
1081                                         // We never write the ChannelClose|HTLCResolution events as they'll be replayed
1082                                         // upon restarting anyway if they remain unresolved.
1083                                         BumpTransactionEvent::ChannelClose { .. } => {}
1084                                         BumpTransactionEvent::HTLCResolution { .. } => {}
1085                                 }
1086                                 write_tlv_fields!(writer, {}); // Write a length field for forwards compat
1087                         }
1088                         &Event::ChannelReady { ref channel_id, ref user_channel_id, ref counterparty_node_id, ref channel_type } => {
1089                                 29u8.write(writer)?;
1090                                 write_tlv_fields!(writer, {
1091                                         (0, channel_id, required),
1092                                         (2, user_channel_id, required),
1093                                         (4, counterparty_node_id, required),
1094                                         (6, channel_type, required),
1095                                 });
1096                         },
1097                         &Event::ChannelPending { ref channel_id, ref user_channel_id, ref former_temporary_channel_id, ref counterparty_node_id, ref funding_txo } => {
1098                                 31u8.write(writer)?;
1099                                 write_tlv_fields!(writer, {
1100                                         (0, channel_id, required),
1101                                         (2, user_channel_id, required),
1102                                         (4, former_temporary_channel_id, required),
1103                                         (6, counterparty_node_id, required),
1104                                         (8, funding_txo, required),
1105                                 });
1106                         },
1107                         // Note that, going forward, all new events must only write data inside of
1108                         // `write_tlv_fields`. Versions 0.0.101+ will ignore odd-numbered events that write
1109                         // data via `write_tlv_fields`.
1110                 }
1111                 Ok(())
1112         }
1113 }
1114 impl MaybeReadable for Event {
1115         fn read<R: io::Read>(reader: &mut R) -> Result<Option<Self>, msgs::DecodeError> {
1116                 match Readable::read(reader)? {
1117                         // Note that we do not write a length-prefixed TLV for FundingGenerationReady events,
1118                         // unlike all other events, thus we return immediately here.
1119                         0u8 => Ok(None),
1120                         1u8 => {
1121                                 let f = || {
1122                                         let mut payment_hash = PaymentHash([0; 32]);
1123                                         let mut payment_preimage = None;
1124                                         let mut payment_secret = None;
1125                                         let mut amount_msat = 0;
1126                                         let mut counterparty_skimmed_fee_msat_opt = None;
1127                                         let mut receiver_node_id = None;
1128                                         let mut _user_payment_id = None::<u64>; // Used in 0.0.103 and earlier, no longer written in 0.0.116+.
1129                                         let mut via_channel_id = None;
1130                                         let mut claim_deadline = None;
1131                                         let mut via_user_channel_id = None;
1132                                         let mut onion_fields = None;
1133                                         read_tlv_fields!(reader, {
1134                                                 (0, payment_hash, required),
1135                                                 (1, receiver_node_id, option),
1136                                                 (2, payment_secret, option),
1137                                                 (3, via_channel_id, option),
1138                                                 (4, amount_msat, required),
1139                                                 (5, via_user_channel_id, option),
1140                                                 (6, _user_payment_id, option),
1141                                                 (7, claim_deadline, option),
1142                                                 (8, payment_preimage, option),
1143                                                 (9, onion_fields, option),
1144                                                 (10, counterparty_skimmed_fee_msat_opt, option),
1145                                         });
1146                                         let purpose = match payment_secret {
1147                                                 Some(secret) => PaymentPurpose::InvoicePayment {
1148                                                         payment_preimage,
1149                                                         payment_secret: secret
1150                                                 },
1151                                                 None if payment_preimage.is_some() => PaymentPurpose::SpontaneousPayment(payment_preimage.unwrap()),
1152                                                 None => return Err(msgs::DecodeError::InvalidValue),
1153                                         };
1154                                         Ok(Some(Event::PaymentClaimable {
1155                                                 receiver_node_id,
1156                                                 payment_hash,
1157                                                 amount_msat,
1158                                                 counterparty_skimmed_fee_msat: counterparty_skimmed_fee_msat_opt.unwrap_or(0),
1159                                                 purpose,
1160                                                 via_channel_id,
1161                                                 via_user_channel_id,
1162                                                 claim_deadline,
1163                                                 onion_fields,
1164                                         }))
1165                                 };
1166                                 f()
1167                         },
1168                         2u8 => {
1169                                 let f = || {
1170                                         let mut payment_preimage = PaymentPreimage([0; 32]);
1171                                         let mut payment_hash = None;
1172                                         let mut payment_id = None;
1173                                         let mut fee_paid_msat = None;
1174                                         read_tlv_fields!(reader, {
1175                                                 (0, payment_preimage, required),
1176                                                 (1, payment_hash, option),
1177                                                 (3, payment_id, option),
1178                                                 (5, fee_paid_msat, option),
1179                                         });
1180                                         if payment_hash.is_none() {
1181                                                 payment_hash = Some(PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()));
1182                                         }
1183                                         Ok(Some(Event::PaymentSent {
1184                                                 payment_id,
1185                                                 payment_preimage,
1186                                                 payment_hash: payment_hash.unwrap(),
1187                                                 fee_paid_msat,
1188                                         }))
1189                                 };
1190                                 f()
1191                         },
1192                         3u8 => {
1193                                 let f = || {
1194                                         #[cfg(test)]
1195                                         let error_code = Readable::read(reader)?;
1196                                         #[cfg(test)]
1197                                         let error_data = Readable::read(reader)?;
1198                                         let mut payment_hash = PaymentHash([0; 32]);
1199                                         let mut payment_failed_permanently = false;
1200                                         let mut network_update = None;
1201                                         let mut blinded_tail: Option<BlindedTail> = None;
1202                                         let mut path: Option<Vec<RouteHop>> = Some(vec![]);
1203                                         let mut short_channel_id = None;
1204                                         let mut payment_id = None;
1205                                         let mut failure_opt = None;
1206                                         read_tlv_fields!(reader, {
1207                                                 (0, payment_hash, required),
1208                                                 (1, network_update, upgradable_option),
1209                                                 (2, payment_failed_permanently, required),
1210                                                 (4, blinded_tail, option),
1211                                                 // Added as a part of LDK 0.0.101 and always filled in since.
1212                                                 // Defaults to an empty Vec, though likely should have been `Option`al.
1213                                                 (5, path, optional_vec),
1214                                                 (7, short_channel_id, option),
1215                                                 (11, payment_id, option),
1216                                                 (13, failure_opt, upgradable_option),
1217                                         });
1218                                         let failure = failure_opt.unwrap_or_else(|| PathFailure::OnPath { network_update });
1219                                         Ok(Some(Event::PaymentPathFailed {
1220                                                 payment_id,
1221                                                 payment_hash,
1222                                                 payment_failed_permanently,
1223                                                 failure,
1224                                                 path: Path { hops: path.unwrap(), blinded_tail },
1225                                                 short_channel_id,
1226                                                 #[cfg(test)]
1227                                                 error_code,
1228                                                 #[cfg(test)]
1229                                                 error_data,
1230                                         }))
1231                                 };
1232                                 f()
1233                         },
1234                         4u8 => Ok(None),
1235                         5u8 => {
1236                                 let f = || {
1237                                         let mut outputs = WithoutLength(Vec::new());
1238                                         let mut channel_id: Option<[u8; 32]> = None;
1239                                         read_tlv_fields!(reader, {
1240                                                 (0, outputs, required),
1241                                                 (1, channel_id, option),
1242                                         });
1243                                         Ok(Some(Event::SpendableOutputs { outputs: outputs.0, channel_id }))
1244                                 };
1245                                 f()
1246                         },
1247                         6u8 => {
1248                                 let mut payment_hash = PaymentHash([0; 32]);
1249                                 let mut intercept_id = InterceptId([0; 32]);
1250                                 let mut requested_next_hop_scid = InterceptNextHop::FakeScid { requested_next_hop_scid: 0 };
1251                                 let mut inbound_amount_msat = 0;
1252                                 let mut expected_outbound_amount_msat = 0;
1253                                 read_tlv_fields!(reader, {
1254                                         (0, intercept_id, required),
1255                                         (2, requested_next_hop_scid, required),
1256                                         (4, payment_hash, required),
1257                                         (6, inbound_amount_msat, required),
1258                                         (8, expected_outbound_amount_msat, required),
1259                                 });
1260                                 let next_scid = match requested_next_hop_scid {
1261                                         InterceptNextHop::FakeScid { requested_next_hop_scid: scid } => scid
1262                                 };
1263                                 Ok(Some(Event::HTLCIntercepted {
1264                                         payment_hash,
1265                                         requested_next_hop_scid: next_scid,
1266                                         inbound_amount_msat,
1267                                         expected_outbound_amount_msat,
1268                                         intercept_id,
1269                                 }))
1270                         },
1271                         7u8 => {
1272                                 let f = || {
1273                                         let mut fee_earned_msat = None;
1274                                         let mut prev_channel_id = None;
1275                                         let mut claim_from_onchain_tx = false;
1276                                         let mut next_channel_id = None;
1277                                         let mut outbound_amount_forwarded_msat = None;
1278                                         read_tlv_fields!(reader, {
1279                                                 (0, fee_earned_msat, option),
1280                                                 (1, prev_channel_id, option),
1281                                                 (2, claim_from_onchain_tx, required),
1282                                                 (3, next_channel_id, option),
1283                                                 (5, outbound_amount_forwarded_msat, option),
1284                                         });
1285                                         Ok(Some(Event::PaymentForwarded {
1286                                                 fee_earned_msat, prev_channel_id, claim_from_onchain_tx, next_channel_id,
1287                                                 outbound_amount_forwarded_msat
1288                                         }))
1289                                 };
1290                                 f()
1291                         },
1292                         9u8 => {
1293                                 let f = || {
1294                                         let mut channel_id = [0; 32];
1295                                         let mut reason = UpgradableRequired(None);
1296                                         let mut user_channel_id_low_opt: Option<u64> = None;
1297                                         let mut user_channel_id_high_opt: Option<u64> = None;
1298                                         let mut counterparty_node_id = None;
1299                                         let mut channel_capacity_sats = None;
1300                                         read_tlv_fields!(reader, {
1301                                                 (0, channel_id, required),
1302                                                 (1, user_channel_id_low_opt, option),
1303                                                 (2, reason, upgradable_required),
1304                                                 (3, user_channel_id_high_opt, option),
1305                                                 (5, counterparty_node_id, option),
1306                                                 (7, channel_capacity_sats, option),
1307                                         });
1308
1309                                         // `user_channel_id` used to be a single u64 value. In order to remain
1310                                         // backwards compatible with versions prior to 0.0.113, the u128 is serialized
1311                                         // as two separate u64 values.
1312                                         let user_channel_id = (user_channel_id_low_opt.unwrap_or(0) as u128) +
1313                                                 ((user_channel_id_high_opt.unwrap_or(0) as u128) << 64);
1314
1315                                         Ok(Some(Event::ChannelClosed { channel_id, user_channel_id, reason: _init_tlv_based_struct_field!(reason, upgradable_required),
1316                                                 counterparty_node_id, channel_capacity_sats }))
1317                                 };
1318                                 f()
1319                         },
1320                         11u8 => {
1321                                 let f = || {
1322                                         let mut channel_id = [0; 32];
1323                                         let mut transaction = Transaction{ version: 2, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() };
1324                                         read_tlv_fields!(reader, {
1325                                                 (0, channel_id, required),
1326                                                 (2, transaction, required),
1327                                         });
1328                                         Ok(Some(Event::DiscardFunding { channel_id, transaction } ))
1329                                 };
1330                                 f()
1331                         },
1332                         13u8 => {
1333                                 let f = || {
1334                                         _init_and_read_tlv_fields!(reader, {
1335                                                 (0, payment_id, required),
1336                                                 (2, payment_hash, option),
1337                                                 (4, path, required_vec),
1338                                                 (6, blinded_tail, option),
1339                                         });
1340                                         Ok(Some(Event::PaymentPathSuccessful {
1341                                                 payment_id: payment_id.0.unwrap(),
1342                                                 payment_hash,
1343                                                 path: Path { hops: path, blinded_tail },
1344                                         }))
1345                                 };
1346                                 f()
1347                         },
1348                         15u8 => {
1349                                 let f = || {
1350                                         let mut payment_hash = PaymentHash([0; 32]);
1351                                         let mut payment_id = PaymentId([0; 32]);
1352                                         let mut reason = None;
1353                                         read_tlv_fields!(reader, {
1354                                                 (0, payment_id, required),
1355                                                 (1, reason, upgradable_option),
1356                                                 (2, payment_hash, required),
1357                                         });
1358                                         Ok(Some(Event::PaymentFailed {
1359                                                 payment_id,
1360                                                 payment_hash,
1361                                                 reason,
1362                                         }))
1363                                 };
1364                                 f()
1365                         },
1366                         17u8 => {
1367                                 // Value 17 is used for `Event::OpenChannelRequest`.
1368                                 Ok(None)
1369                         },
1370                         19u8 => {
1371                                 let f = || {
1372                                         let mut payment_hash = PaymentHash([0; 32]);
1373                                         let mut purpose = UpgradableRequired(None);
1374                                         let mut amount_msat = 0;
1375                                         let mut receiver_node_id = None;
1376                                         read_tlv_fields!(reader, {
1377                                                 (0, payment_hash, required),
1378                                                 (1, receiver_node_id, option),
1379                                                 (2, purpose, upgradable_required),
1380                                                 (4, amount_msat, required),
1381                                         });
1382                                         Ok(Some(Event::PaymentClaimed {
1383                                                 receiver_node_id,
1384                                                 payment_hash,
1385                                                 purpose: _init_tlv_based_struct_field!(purpose, upgradable_required),
1386                                                 amount_msat,
1387                                         }))
1388                                 };
1389                                 f()
1390                         },
1391                         21u8 => {
1392                                 let f = || {
1393                                         _init_and_read_tlv_fields!(reader, {
1394                                                 (0, payment_id, required),
1395                                                 (2, payment_hash, required),
1396                                                 (4, path, required_vec),
1397                                                 (6, blinded_tail, option),
1398                                         });
1399                                         Ok(Some(Event::ProbeSuccessful {
1400                                                 payment_id: payment_id.0.unwrap(),
1401                                                 payment_hash: payment_hash.0.unwrap(),
1402                                                 path: Path { hops: path, blinded_tail },
1403                                         }))
1404                                 };
1405                                 f()
1406                         },
1407                         23u8 => {
1408                                 let f = || {
1409                                         _init_and_read_tlv_fields!(reader, {
1410                                                 (0, payment_id, required),
1411                                                 (2, payment_hash, required),
1412                                                 (4, path, required_vec),
1413                                                 (6, short_channel_id, option),
1414                                                 (8, blinded_tail, option),
1415                                         });
1416                                         Ok(Some(Event::ProbeFailed {
1417                                                 payment_id: payment_id.0.unwrap(),
1418                                                 payment_hash: payment_hash.0.unwrap(),
1419                                                 path: Path { hops: path, blinded_tail },
1420                                                 short_channel_id,
1421                                         }))
1422                                 };
1423                                 f()
1424                         },
1425                         25u8 => {
1426                                 let f = || {
1427                                         let mut prev_channel_id = [0; 32];
1428                                         let mut failed_next_destination_opt = UpgradableRequired(None);
1429                                         read_tlv_fields!(reader, {
1430                                                 (0, prev_channel_id, required),
1431                                                 (2, failed_next_destination_opt, upgradable_required),
1432                                         });
1433                                         Ok(Some(Event::HTLCHandlingFailed {
1434                                                 prev_channel_id,
1435                                                 failed_next_destination: _init_tlv_based_struct_field!(failed_next_destination_opt, upgradable_required),
1436                                         }))
1437                                 };
1438                                 f()
1439                         },
1440                         27u8 => Ok(None),
1441                         29u8 => {
1442                                 let f = || {
1443                                         let mut channel_id = [0; 32];
1444                                         let mut user_channel_id: u128 = 0;
1445                                         let mut counterparty_node_id = RequiredWrapper(None);
1446                                         let mut channel_type = RequiredWrapper(None);
1447                                         read_tlv_fields!(reader, {
1448                                                 (0, channel_id, required),
1449                                                 (2, user_channel_id, required),
1450                                                 (4, counterparty_node_id, required),
1451                                                 (6, channel_type, required),
1452                                         });
1453
1454                                         Ok(Some(Event::ChannelReady {
1455                                                 channel_id,
1456                                                 user_channel_id,
1457                                                 counterparty_node_id: counterparty_node_id.0.unwrap(),
1458                                                 channel_type: channel_type.0.unwrap()
1459                                         }))
1460                                 };
1461                                 f()
1462                         },
1463                         31u8 => {
1464                                 let f = || {
1465                                         let mut channel_id = [0; 32];
1466                                         let mut user_channel_id: u128 = 0;
1467                                         let mut former_temporary_channel_id = None;
1468                                         let mut counterparty_node_id = RequiredWrapper(None);
1469                                         let mut funding_txo = RequiredWrapper(None);
1470                                         read_tlv_fields!(reader, {
1471                                                 (0, channel_id, required),
1472                                                 (2, user_channel_id, required),
1473                                                 (4, former_temporary_channel_id, required),
1474                                                 (6, counterparty_node_id, required),
1475                                                 (8, funding_txo, required),
1476                                         });
1477
1478                                         Ok(Some(Event::ChannelPending {
1479                                                 channel_id,
1480                                                 user_channel_id,
1481                                                 former_temporary_channel_id,
1482                                                 counterparty_node_id: counterparty_node_id.0.unwrap(),
1483                                                 funding_txo: funding_txo.0.unwrap()
1484                                         }))
1485                                 };
1486                                 f()
1487                         },
1488                         // Versions prior to 0.0.100 did not ignore odd types, instead returning InvalidValue.
1489                         // Version 0.0.100 failed to properly ignore odd types, possibly resulting in corrupt
1490                         // reads.
1491                         x if x % 2 == 1 => {
1492                                 // If the event is of unknown type, assume it was written with `write_tlv_fields`,
1493                                 // which prefixes the whole thing with a length BigSize. Because the event is
1494                                 // odd-type unknown, we should treat it as `Ok(None)` even if it has some TLV
1495                                 // fields that are even. Thus, we avoid using `read_tlv_fields` and simply read
1496                                 // exactly the number of bytes specified, ignoring them entirely.
1497                                 let tlv_len: BigSize = Readable::read(reader)?;
1498                                 FixedLengthReader::new(reader, tlv_len.0)
1499                                         .eat_remaining().map_err(|_| msgs::DecodeError::ShortRead)?;
1500                                 Ok(None)
1501                         },
1502                         _ => Err(msgs::DecodeError::InvalidValue)
1503                 }
1504         }
1505 }
1506
1507 /// An event generated by ChannelManager which indicates a message should be sent to a peer (or
1508 /// broadcast to most peers).
1509 /// These events are handled by PeerManager::process_events if you are using a PeerManager.
1510 #[derive(Clone, Debug)]
1511 pub enum MessageSendEvent {
1512         /// Used to indicate that we've accepted a channel open and should send the accept_channel
1513         /// message provided to the given peer.
1514         SendAcceptChannel {
1515                 /// The node_id of the node which should receive this message
1516                 node_id: PublicKey,
1517                 /// The message which should be sent.
1518                 msg: msgs::AcceptChannel,
1519         },
1520         /// Used to indicate that we've accepted a V2 channel open and should send the accept_channel2
1521         /// message provided to the given peer.
1522         SendAcceptChannelV2 {
1523                 /// The node_id of the node which should receive this message
1524                 node_id: PublicKey,
1525                 /// The message which should be sent.
1526                 msg: msgs::AcceptChannelV2,
1527         },
1528         /// Used to indicate that we've initiated a channel open and should send the open_channel
1529         /// message provided to the given peer.
1530         SendOpenChannel {
1531                 /// The node_id of the node which should receive this message
1532                 node_id: PublicKey,
1533                 /// The message which should be sent.
1534                 msg: msgs::OpenChannel,
1535         },
1536         /// Used to indicate that we've initiated a V2 channel open and should send the open_channel2
1537         /// message provided to the given peer.
1538         SendOpenChannelV2 {
1539                 /// The node_id of the node which should receive this message
1540                 node_id: PublicKey,
1541                 /// The message which should be sent.
1542                 msg: msgs::OpenChannelV2,
1543         },
1544         /// Used to indicate that a funding_created message should be sent to the peer with the given node_id.
1545         SendFundingCreated {
1546                 /// The node_id of the node which should receive this message
1547                 node_id: PublicKey,
1548                 /// The message which should be sent.
1549                 msg: msgs::FundingCreated,
1550         },
1551         /// Used to indicate that a funding_signed message should be sent to the peer with the given node_id.
1552         SendFundingSigned {
1553                 /// The node_id of the node which should receive this message
1554                 node_id: PublicKey,
1555                 /// The message which should be sent.
1556                 msg: msgs::FundingSigned,
1557         },
1558         /// Used to indicate that a tx_add_input message should be sent to the peer with the given node_id.
1559         SendTxAddInput {
1560                 /// The node_id of the node which should receive this message
1561                 node_id: PublicKey,
1562                 /// The message which should be sent.
1563                 msg: msgs::TxAddInput,
1564         },
1565         /// Used to indicate that a tx_add_output message should be sent to the peer with the given node_id.
1566         SendTxAddOutput {
1567                 /// The node_id of the node which should receive this message
1568                 node_id: PublicKey,
1569                 /// The message which should be sent.
1570                 msg: msgs::TxAddOutput,
1571         },
1572         /// Used to indicate that a tx_remove_input message should be sent to the peer with the given node_id.
1573         SendTxRemoveInput {
1574                 /// The node_id of the node which should receive this message
1575                 node_id: PublicKey,
1576                 /// The message which should be sent.
1577                 msg: msgs::TxRemoveInput,
1578         },
1579         /// Used to indicate that a tx_remove_output message should be sent to the peer with the given node_id.
1580         SendTxRemoveOutput {
1581                 /// The node_id of the node which should receive this message
1582                 node_id: PublicKey,
1583                 /// The message which should be sent.
1584                 msg: msgs::TxRemoveOutput,
1585         },
1586         /// Used to indicate that a tx_complete message should be sent to the peer with the given node_id.
1587         SendTxComplete {
1588                 /// The node_id of the node which should receive this message
1589                 node_id: PublicKey,
1590                 /// The message which should be sent.
1591                 msg: msgs::TxComplete,
1592         },
1593         /// Used to indicate that a tx_signatures message should be sent to the peer with the given node_id.
1594         SendTxSignatures {
1595                 /// The node_id of the node which should receive this message
1596                 node_id: PublicKey,
1597                 /// The message which should be sent.
1598                 msg: msgs::TxSignatures,
1599         },
1600         /// Used to indicate that a tx_init_rbf message should be sent to the peer with the given node_id.
1601         SendTxInitRbf {
1602                 /// The node_id of the node which should receive this message
1603                 node_id: PublicKey,
1604                 /// The message which should be sent.
1605                 msg: msgs::TxInitRbf,
1606         },
1607         /// Used to indicate that a tx_ack_rbf message should be sent to the peer with the given node_id.
1608         SendTxAckRbf {
1609                 /// The node_id of the node which should receive this message
1610                 node_id: PublicKey,
1611                 /// The message which should be sent.
1612                 msg: msgs::TxAckRbf,
1613         },
1614         /// Used to indicate that a tx_abort message should be sent to the peer with the given node_id.
1615         SendTxAbort {
1616                 /// The node_id of the node which should receive this message
1617                 node_id: PublicKey,
1618                 /// The message which should be sent.
1619                 msg: msgs::TxAddInput,
1620         },
1621         /// Used to indicate that a channel_ready message should be sent to the peer with the given node_id.
1622         SendChannelReady {
1623                 /// The node_id of the node which should receive these message(s)
1624                 node_id: PublicKey,
1625                 /// The channel_ready message which should be sent.
1626                 msg: msgs::ChannelReady,
1627         },
1628         /// Used to indicate that an announcement_signatures message should be sent to the peer with the given node_id.
1629         SendAnnouncementSignatures {
1630                 /// The node_id of the node which should receive these message(s)
1631                 node_id: PublicKey,
1632                 /// The announcement_signatures message which should be sent.
1633                 msg: msgs::AnnouncementSignatures,
1634         },
1635         /// Used to indicate that a series of HTLC update messages, as well as a commitment_signed
1636         /// message should be sent to the peer with the given node_id.
1637         UpdateHTLCs {
1638                 /// The node_id of the node which should receive these message(s)
1639                 node_id: PublicKey,
1640                 /// The update messages which should be sent. ALL messages in the struct should be sent!
1641                 updates: msgs::CommitmentUpdate,
1642         },
1643         /// Used to indicate that a revoke_and_ack message should be sent to the peer with the given node_id.
1644         SendRevokeAndACK {
1645                 /// The node_id of the node which should receive this message
1646                 node_id: PublicKey,
1647                 /// The message which should be sent.
1648                 msg: msgs::RevokeAndACK,
1649         },
1650         /// Used to indicate that a closing_signed message should be sent to the peer with the given node_id.
1651         SendClosingSigned {
1652                 /// The node_id of the node which should receive this message
1653                 node_id: PublicKey,
1654                 /// The message which should be sent.
1655                 msg: msgs::ClosingSigned,
1656         },
1657         /// Used to indicate that a shutdown message should be sent to the peer with the given node_id.
1658         SendShutdown {
1659                 /// The node_id of the node which should receive this message
1660                 node_id: PublicKey,
1661                 /// The message which should be sent.
1662                 msg: msgs::Shutdown,
1663         },
1664         /// Used to indicate that a channel_reestablish message should be sent to the peer with the given node_id.
1665         SendChannelReestablish {
1666                 /// The node_id of the node which should receive this message
1667                 node_id: PublicKey,
1668                 /// The message which should be sent.
1669                 msg: msgs::ChannelReestablish,
1670         },
1671         /// Used to send a channel_announcement and channel_update to a specific peer, likely on
1672         /// initial connection to ensure our peers know about our channels.
1673         SendChannelAnnouncement {
1674                 /// The node_id of the node which should receive this message
1675                 node_id: PublicKey,
1676                 /// The channel_announcement which should be sent.
1677                 msg: msgs::ChannelAnnouncement,
1678                 /// The followup channel_update which should be sent.
1679                 update_msg: msgs::ChannelUpdate,
1680         },
1681         /// Used to indicate that a channel_announcement and channel_update should be broadcast to all
1682         /// peers (except the peer with node_id either msg.contents.node_id_1 or msg.contents.node_id_2).
1683         ///
1684         /// Note that after doing so, you very likely (unless you did so very recently) want to
1685         /// broadcast a node_announcement (e.g. via [`PeerManager::broadcast_node_announcement`]). This
1686         /// ensures that any nodes which see our channel_announcement also have a relevant
1687         /// node_announcement, including relevant feature flags which may be important for routing
1688         /// through or to us.
1689         ///
1690         /// [`PeerManager::broadcast_node_announcement`]: crate::ln::peer_handler::PeerManager::broadcast_node_announcement
1691         BroadcastChannelAnnouncement {
1692                 /// The channel_announcement which should be sent.
1693                 msg: msgs::ChannelAnnouncement,
1694                 /// The followup channel_update which should be sent.
1695                 update_msg: Option<msgs::ChannelUpdate>,
1696         },
1697         /// Used to indicate that a channel_update should be broadcast to all peers.
1698         BroadcastChannelUpdate {
1699                 /// The channel_update which should be sent.
1700                 msg: msgs::ChannelUpdate,
1701         },
1702         /// Used to indicate that a node_announcement should be broadcast to all peers.
1703         BroadcastNodeAnnouncement {
1704                 /// The node_announcement which should be sent.
1705                 msg: msgs::NodeAnnouncement,
1706         },
1707         /// Used to indicate that a channel_update should be sent to a single peer.
1708         /// In contrast to [`Self::BroadcastChannelUpdate`], this is used when the channel is a
1709         /// private channel and we shouldn't be informing all of our peers of channel parameters.
1710         SendChannelUpdate {
1711                 /// The node_id of the node which should receive this message
1712                 node_id: PublicKey,
1713                 /// The channel_update which should be sent.
1714                 msg: msgs::ChannelUpdate,
1715         },
1716         /// Broadcast an error downstream to be handled
1717         HandleError {
1718                 /// The node_id of the node which should receive this message
1719                 node_id: PublicKey,
1720                 /// The action which should be taken.
1721                 action: msgs::ErrorAction
1722         },
1723         /// Query a peer for channels with funding transaction UTXOs in a block range.
1724         SendChannelRangeQuery {
1725                 /// The node_id of this message recipient
1726                 node_id: PublicKey,
1727                 /// The query_channel_range which should be sent.
1728                 msg: msgs::QueryChannelRange,
1729         },
1730         /// Request routing gossip messages from a peer for a list of channels identified by
1731         /// their short_channel_ids.
1732         SendShortIdsQuery {
1733                 /// The node_id of this message recipient
1734                 node_id: PublicKey,
1735                 /// The query_short_channel_ids which should be sent.
1736                 msg: msgs::QueryShortChannelIds,
1737         },
1738         /// Sends a reply to a channel range query. This may be one of several SendReplyChannelRange events
1739         /// emitted during processing of the query.
1740         SendReplyChannelRange {
1741                 /// The node_id of this message recipient
1742                 node_id: PublicKey,
1743                 /// The reply_channel_range which should be sent.
1744                 msg: msgs::ReplyChannelRange,
1745         },
1746         /// Sends a timestamp filter for inbound gossip. This should be sent on each new connection to
1747         /// enable receiving gossip messages from the peer.
1748         SendGossipTimestampFilter {
1749                 /// The node_id of this message recipient
1750                 node_id: PublicKey,
1751                 /// The gossip_timestamp_filter which should be sent.
1752                 msg: msgs::GossipTimestampFilter,
1753         },
1754 }
1755
1756 /// A trait indicating an object may generate message send events
1757 pub trait MessageSendEventsProvider {
1758         /// Gets the list of pending events which were generated by previous actions, clearing the list
1759         /// in the process.
1760         fn get_and_clear_pending_msg_events(&self) -> Vec<MessageSendEvent>;
1761 }
1762
1763 /// A trait indicating an object may generate onion messages to send
1764 pub trait OnionMessageProvider {
1765         /// Gets the next pending onion message for the peer with the given node id.
1766         fn next_onion_message_for_peer(&self, peer_node_id: PublicKey) -> Option<msgs::OnionMessage>;
1767 }
1768
1769 /// A trait indicating an object may generate events.
1770 ///
1771 /// Events are processed by passing an [`EventHandler`] to [`process_pending_events`].
1772 ///
1773 /// Implementations of this trait may also feature an async version of event handling, as shown with
1774 /// [`ChannelManager::process_pending_events_async`] and
1775 /// [`ChainMonitor::process_pending_events_async`].
1776 ///
1777 /// # Requirements
1778 ///
1779 /// When using this trait, [`process_pending_events`] will call [`handle_event`] for each pending
1780 /// event since the last invocation.
1781 ///
1782 /// In order to ensure no [`Event`]s are lost, implementors of this trait will persist [`Event`]s
1783 /// and replay any unhandled events on startup. An [`Event`] is considered handled when
1784 /// [`process_pending_events`] returns, thus handlers MUST fully handle [`Event`]s and persist any
1785 /// relevant changes to disk *before* returning.
1786 ///
1787 /// Further, because an application may crash between an [`Event`] being handled and the
1788 /// implementor of this trait being re-serialized, [`Event`] handling must be idempotent - in
1789 /// effect, [`Event`]s may be replayed.
1790 ///
1791 /// Note, handlers may call back into the provider and thus deadlocking must be avoided. Be sure to
1792 /// consult the provider's documentation on the implication of processing events and how a handler
1793 /// may safely use the provider (e.g., see [`ChannelManager::process_pending_events`] and
1794 /// [`ChainMonitor::process_pending_events`]).
1795 ///
1796 /// (C-not implementable) As there is likely no reason for a user to implement this trait on their
1797 /// own type(s).
1798 ///
1799 /// [`process_pending_events`]: Self::process_pending_events
1800 /// [`handle_event`]: EventHandler::handle_event
1801 /// [`ChannelManager::process_pending_events`]: crate::ln::channelmanager::ChannelManager#method.process_pending_events
1802 /// [`ChainMonitor::process_pending_events`]: crate::chain::chainmonitor::ChainMonitor#method.process_pending_events
1803 /// [`ChannelManager::process_pending_events_async`]: crate::ln::channelmanager::ChannelManager::process_pending_events_async
1804 /// [`ChainMonitor::process_pending_events_async`]: crate::chain::chainmonitor::ChainMonitor::process_pending_events_async
1805 pub trait EventsProvider {
1806         /// Processes any events generated since the last call using the given event handler.
1807         ///
1808         /// See the trait-level documentation for requirements.
1809         fn process_pending_events<H: Deref>(&self, handler: H) where H::Target: EventHandler;
1810 }
1811
1812 /// A trait implemented for objects handling events from [`EventsProvider`].
1813 ///
1814 /// An async variation also exists for implementations of [`EventsProvider`] that support async
1815 /// event handling. The async event handler should satisfy the generic bounds: `F:
1816 /// core::future::Future, H: Fn(Event) -> F`.
1817 pub trait EventHandler {
1818         /// Handles the given [`Event`].
1819         ///
1820         /// See [`EventsProvider`] for details that must be considered when implementing this method.
1821         fn handle_event(&self, event: Event);
1822 }
1823
1824 impl<F> EventHandler for F where F: Fn(Event) {
1825         fn handle_event(&self, event: Event) {
1826                 self(event)
1827         }
1828 }
1829
1830 impl<T: EventHandler> EventHandler for Arc<T> {
1831         fn handle_event(&self, event: Event) {
1832                 self.deref().handle_event(event)
1833         }
1834 }