git.bitcoin.ninja Git - rust-lightning/blob - lightning-invoice/src/utils.rs

   1 //! Convenient utilities to create an invoice.
   2
   3 use crate::{CreationError, Currency, Invoice, InvoiceBuilder, SignOrCreationError};
   4
   5 use crate::{prelude::*, Description, InvoiceDescription, Sha256};
   6 use bech32::ToBase32;
   7 use bitcoin_hashes::Hash;
   8 use lightning::chain;
   9 use lightning::chain::chaininterface::{BroadcasterInterface, FeeEstimator};
  10 use lightning::sign::{Recipient, NodeSigner, SignerProvider, EntropySource};
  11 use lightning::ln::{PaymentHash, PaymentSecret};
  12 use lightning::ln::channelmanager::{ChannelDetails, ChannelManager, MIN_FINAL_CLTV_EXPIRY_DELTA};
  13 use lightning::ln::channelmanager::{PhantomRouteHints, MIN_CLTV_EXPIRY_DELTA};
  14 use lightning::ln::inbound_payment::{create, create_from_hash, ExpandedKey};
  15 use lightning::routing::gossip::RoutingFees;
  16 use lightning::routing::router::{RouteHint, RouteHintHop, Router};
  17 use lightning::util::logger::Logger;
  18 use secp256k1::PublicKey;
  19 use core::ops::Deref;
  20 use core::time::Duration;
  21
  22 /// Utility to create an invoice that can be paid to one of multiple nodes, or a "phantom invoice."
  23 /// See [`PhantomKeysManager`] for more information on phantom node payments.
  24 ///
  25 /// `phantom_route_hints` parameter:
  26 /// * Contains channel info for all nodes participating in the phantom invoice
  27 /// * Entries are retrieved from a call to [`ChannelManager::get_phantom_route_hints`] on each
  28 ///   participating node
  29 /// * It is fine to cache `phantom_route_hints` and reuse it across invoices, as long as the data is
  30 ///   updated when a channel becomes disabled or closes
  31 /// * Note that if too many channels are included in [`PhantomRouteHints::channels`], the invoice
  32 ///   may be too long for QR code scanning. To fix this, `PhantomRouteHints::channels` may be pared
  33 ///   down
  34 ///
  35 /// `payment_hash` can be specified if you have a specific need for a custom payment hash (see the difference
  36 /// between [`ChannelManager::create_inbound_payment`] and [`ChannelManager::create_inbound_payment_for_hash`]).
  37 /// If `None` is provided for `payment_hash`, then one will be created.
  38 ///
  39 /// `invoice_expiry_delta_secs` describes the number of seconds that the invoice is valid for
  40 /// in excess of the current time.
  41 ///
  42 /// `duration_since_epoch` is the current time since epoch in seconds.
  43 ///
  44 /// You can specify a custom `min_final_cltv_expiry_delta`, or let LDK default it to
  45 /// [`MIN_FINAL_CLTV_EXPIRY_DELTA`]. The provided expiry must be at least [`MIN_FINAL_CLTV_EXPIRY_DELTA`] - 3.
  46 /// Note that LDK will add a buffer of 3 blocks to the delta to allow for up to a few new block
  47 /// confirmations during routing.
  48 ///
  49 /// Note that the provided `keys_manager`'s `NodeSigner` implementation must support phantom
  50 /// invoices in its `sign_invoice` implementation ([`PhantomKeysManager`] satisfies this
  51 /// requirement).
  52 ///
  53 /// [`PhantomKeysManager`]: lightning::sign::PhantomKeysManager
  54 /// [`ChannelManager::get_phantom_route_hints`]: lightning::ln::channelmanager::ChannelManager::get_phantom_route_hints
  55 /// [`ChannelManager::create_inbound_payment`]: lightning::ln::channelmanager::ChannelManager::create_inbound_payment
  56 /// [`ChannelManager::create_inbound_payment_for_hash`]: lightning::ln::channelmanager::ChannelManager::create_inbound_payment_for_hash
  57 /// [`PhantomRouteHints::channels`]: lightning::ln::channelmanager::PhantomRouteHints::channels
  58 /// [`MIN_FINAL_CLTV_EXPIRY_DETLA`]: lightning::ln::channelmanager::MIN_FINAL_CLTV_EXPIRY_DELTA
  59 ///
  60 /// This can be used in a `no_std` environment, where [`std::time::SystemTime`] is not
  61 /// available and the current time is supplied by the caller.
  62 pub fn create_phantom_invoice<ES: Deref, NS: Deref, L: Deref>(
  63         amt_msat: Option<u64>, payment_hash: Option<PaymentHash>, description: String,
  64         invoice_expiry_delta_secs: u32, phantom_route_hints: Vec<PhantomRouteHints>, entropy_source: ES,
  65         node_signer: NS, logger: L, network: Currency, min_final_cltv_expiry_delta: Option<u16>, duration_since_epoch: Duration,
  66 ) -> Result<Invoice, SignOrCreationError<()>>
  67 where
  68         ES::Target: EntropySource,
  69         NS::Target: NodeSigner,
  70         L::Target: Logger,
  71 {
  72         let description = Description::new(description).map_err(SignOrCreationError::CreationError)?;
  73         let description = InvoiceDescription::Direct(&description,);
  74         _create_phantom_invoice::<ES, NS, L>(
  75                 amt_msat, payment_hash, description, invoice_expiry_delta_secs, phantom_route_hints,
  76                 entropy_source, node_signer, logger, network, min_final_cltv_expiry_delta, duration_since_epoch,
  77         )
  78 }
  79
  80 /// Utility to create an invoice that can be paid to one of multiple nodes, or a "phantom invoice."
  81 /// See [`PhantomKeysManager`] for more information on phantom node payments.
  82 ///
  83 /// `phantom_route_hints` parameter:
  84 /// * Contains channel info for all nodes participating in the phantom invoice
  85 /// * Entries are retrieved from a call to [`ChannelManager::get_phantom_route_hints`] on each
  86 ///   participating node
  87 /// * It is fine to cache `phantom_route_hints` and reuse it across invoices, as long as the data is
  88 ///   updated when a channel becomes disabled or closes
  89 /// * Note that the route hints generated from `phantom_route_hints` will be limited to a maximum
  90 ///   of 3 hints to ensure that the invoice can be scanned in a QR code. These hints are selected
  91 ///   in the order that the nodes in `PhantomRouteHints` are specified, selecting one hint per node
  92 ///   until the maximum is hit. Callers may provide as many `PhantomRouteHints::channels` as
  93 ///   desired, but note that some nodes will be trimmed if more than 3 nodes are provided.
  94 ///
  95 /// `description_hash` is a SHA-256 hash of the description text
  96 ///
  97 /// `payment_hash` can be specified if you have a specific need for a custom payment hash (see the difference
  98 /// between [`ChannelManager::create_inbound_payment`] and [`ChannelManager::create_inbound_payment_for_hash`]).
  99 /// If `None` is provided for `payment_hash`, then one will be created.
 100 ///
 101 /// `invoice_expiry_delta_secs` describes the number of seconds that the invoice is valid for
 102 /// in excess of the current time.
 103 ///
 104 /// `duration_since_epoch` is the current time since epoch in seconds.
 105 ///
 106 /// Note that the provided `keys_manager`'s `NodeSigner` implementation must support phantom
 107 /// invoices in its `sign_invoice` implementation ([`PhantomKeysManager`] satisfies this
 108 /// requirement).
 109 ///
 110 /// [`PhantomKeysManager`]: lightning::sign::PhantomKeysManager
 111 /// [`ChannelManager::get_phantom_route_hints`]: lightning::ln::channelmanager::ChannelManager::get_phantom_route_hints
 112 /// [`ChannelManager::create_inbound_payment`]: lightning::ln::channelmanager::ChannelManager::create_inbound_payment
 113 /// [`ChannelManager::create_inbound_payment_for_hash`]: lightning::ln::channelmanager::ChannelManager::create_inbound_payment_for_hash
 114 /// [`PhantomRouteHints::channels`]: lightning::ln::channelmanager::PhantomRouteHints::channels
 115 ///
 116 /// This can be used in a `no_std` environment, where [`std::time::SystemTime`] is not
 117 /// available and the current time is supplied by the caller.
 118 pub fn create_phantom_invoice_with_description_hash<ES: Deref, NS: Deref, L: Deref>(
 119         amt_msat: Option<u64>, payment_hash: Option<PaymentHash>, invoice_expiry_delta_secs: u32,
 120         description_hash: Sha256, phantom_route_hints: Vec<PhantomRouteHints>, entropy_source: ES,
 121         node_signer: NS, logger: L, network: Currency, min_final_cltv_expiry_delta: Option<u16>, duration_since_epoch: Duration,
 122 ) -> Result<Invoice, SignOrCreationError<()>>
 123 where
 124         ES::Target: EntropySource,
 125         NS::Target: NodeSigner,
 126         L::Target: Logger,
 127 {
 128         _create_phantom_invoice::<ES, NS, L>(
 129                 amt_msat, payment_hash, InvoiceDescription::Hash(&description_hash),
 130                 invoice_expiry_delta_secs, phantom_route_hints, entropy_source, node_signer, logger, network,
 131                 min_final_cltv_expiry_delta, duration_since_epoch,
 132         )
 133 }
 134
 135 fn _create_phantom_invoice<ES: Deref, NS: Deref, L: Deref>(
 136         amt_msat: Option<u64>, payment_hash: Option<PaymentHash>, description: InvoiceDescription,
 137         invoice_expiry_delta_secs: u32, phantom_route_hints: Vec<PhantomRouteHints>, entropy_source: ES,
 138         node_signer: NS, logger: L, network: Currency, min_final_cltv_expiry_delta: Option<u16>, duration_since_epoch: Duration,
 139 ) -> Result<Invoice, SignOrCreationError<()>>
 140 where
 141         ES::Target: EntropySource,
 142         NS::Target: NodeSigner,
 143         L::Target: Logger,
 144 {
 145
 146         if phantom_route_hints.is_empty() {
 147                 return Err(SignOrCreationError::CreationError(
 148                         CreationError::MissingRouteHints,
 149                 ));
 150         }
 151
 152         if min_final_cltv_expiry_delta.is_some() && min_final_cltv_expiry_delta.unwrap().saturating_add(3) < MIN_FINAL_CLTV_EXPIRY_DELTA {
 153                 return Err(SignOrCreationError::CreationError(CreationError::MinFinalCltvExpiryDeltaTooShort));
 154         }
 155
 156         let invoice = match description {
 157                 InvoiceDescription::Direct(description) => {
 158                         InvoiceBuilder::new(network).description(description.0.clone())
 159                 }
 160                 InvoiceDescription::Hash(hash) => InvoiceBuilder::new(network).description_hash(hash.0),
 161         };
 162
 163         // If we ever see performance here being too slow then we should probably take this ExpandedKey as a parameter instead.
 164         let keys = ExpandedKey::new(&node_signer.get_inbound_payment_key_material());
 165         let (payment_hash, payment_secret) = if let Some(payment_hash) = payment_hash {
 166                 let payment_secret = create_from_hash(
 167                         &keys,
 168                         amt_msat,
 169                         payment_hash,
 170                         invoice_expiry_delta_secs,
 171                         duration_since_epoch
 172                                 .as_secs(),
 173                         min_final_cltv_expiry_delta,
 174                 )
 175                 .map_err(|_| SignOrCreationError::CreationError(CreationError::InvalidAmount))?;
 176                 (payment_hash, payment_secret)
 177         } else {
 178                 create(
 179                         &keys,
 180                         amt_msat,
 181                         invoice_expiry_delta_secs,
 182                         &entropy_source,
 183                         duration_since_epoch
 184                                 .as_secs(),
 185                         min_final_cltv_expiry_delta,
 186                 )
 187                 .map_err(|_| SignOrCreationError::CreationError(CreationError::InvalidAmount))?
 188         };
 189
 190         log_trace!(logger, "Creating phantom invoice from {} participating nodes with payment hash {}",
 191                 phantom_route_hints.len(), log_bytes!(payment_hash.0));
 192
 193         let mut invoice = invoice
 194                 .duration_since_epoch(duration_since_epoch)
 195                 .payment_hash(Hash::from_slice(&payment_hash.0).unwrap())
 196                 .payment_secret(payment_secret)
 197                 .min_final_cltv_expiry_delta(
 198                         // Add a buffer of 3 to the delta if present, otherwise use LDK's minimum.
 199                         min_final_cltv_expiry_delta.map(|x| x.saturating_add(3)).unwrap_or(MIN_FINAL_CLTV_EXPIRY_DELTA).into())
 200                 .expiry_time(Duration::from_secs(invoice_expiry_delta_secs.into()));
 201         if let Some(amt) = amt_msat {
 202                 invoice = invoice.amount_milli_satoshis(amt);
 203         }
 204
 205         for route_hint in select_phantom_hints(amt_msat, phantom_route_hints, logger) {
 206                 invoice = invoice.private_route(route_hint);
 207         }
 208
 209         let raw_invoice = match invoice.build_raw() {
 210                 Ok(inv) => inv,
 211                 Err(e) => return Err(SignOrCreationError::CreationError(e))
 212         };
 213         let hrp_str = raw_invoice.hrp.to_string();
 214         let hrp_bytes = hrp_str.as_bytes();
 215         let data_without_signature = raw_invoice.data.to_base32();
 216         let signed_raw_invoice = raw_invoice.sign(|_| node_signer.sign_invoice(hrp_bytes, &data_without_signature, Recipient::PhantomNode));
 217         match signed_raw_invoice {
 218                 Ok(inv) => Ok(Invoice::from_signed(inv).unwrap()),
 219                 Err(e) => Err(SignOrCreationError::SignError(e))
 220         }
 221 }
 222
 223 /// Utility to select route hints for phantom invoices.
 224 /// See [`PhantomKeysManager`] for more information on phantom node payments.
 225 ///
 226 /// To ensure that the phantom invoice is still readable by QR code, we limit to 3 hints per invoice:
 227 /// * Select up to three channels per node.
 228 /// * Select one hint from each node, up to three hints or until we run out of hints.
 229 ///
 230 /// [`PhantomKeysManager`]: lightning::sign::PhantomKeysManager
 231 fn select_phantom_hints<L: Deref>(amt_msat: Option<u64>, phantom_route_hints: Vec<PhantomRouteHints>,
 232         logger: L) -> Vec<RouteHint>
 233 where
 234         L::Target: Logger,
 235 {
 236         let mut phantom_hints: Vec<Vec<RouteHint>> = Vec::new();
 237
 238         for PhantomRouteHints { channels, phantom_scid, real_node_pubkey } in phantom_route_hints {
 239                 log_trace!(logger, "Generating phantom route hints for node {}",
 240                         log_pubkey!(real_node_pubkey));
 241                 let mut route_hints = sort_and_filter_channels(channels, amt_msat, &logger);
 242
 243                 // If we have any public channel, the route hints from `sort_and_filter_channels` will be
 244                 // empty. In that case we create a RouteHint on which we will push a single hop with the
 245                 // phantom route into the invoice, and let the sender find the path to the `real_node_pubkey`
 246                 // node by looking at our public channels.
 247                 if route_hints.is_empty() {
 248                         route_hints.push(RouteHint(vec![]))
 249                 }
 250                 for route_hint in &mut route_hints {
 251                         route_hint.0.push(RouteHintHop {
 252                                 src_node_id: real_node_pubkey,
 253                                 short_channel_id: phantom_scid,
 254                                 fees: RoutingFees {
 255                                         base_msat: 0,
 256                                         proportional_millionths: 0,
 257                                 },
 258                                 cltv_expiry_delta: MIN_CLTV_EXPIRY_DELTA,
 259                                 htlc_minimum_msat: None,
 260                                 htlc_maximum_msat: None,});
 261                 }
 262
 263                 phantom_hints.push(route_hints);
 264         }
 265
 266         // We have one vector per real node involved in creating the phantom invoice. To distribute
 267         // the hints across our real nodes we add one hint from each in turn until no node has any hints
 268         // left (if one node has more hints than any other, these will accumulate at the end of the
 269         // vector).
 270         let mut invoice_hints: Vec<RouteHint> = Vec::new();
 271         let mut hint_idx = 0;
 272
 273         loop {
 274                 let mut remaining_hints = false;
 275
 276                 for hints in phantom_hints.iter() {
 277                         if invoice_hints.len() == 3 {
 278                                 return invoice_hints
 279                         }
 280
 281                         if hint_idx < hints.len() {
 282                                 invoice_hints.push(hints[hint_idx].clone());
 283                                 remaining_hints = true
 284                         }
 285                 }
 286
 287                 if !remaining_hints {
 288                         return invoice_hints
 289                 }
 290
 291                 hint_idx +=1;
 292         }
 293 }
 294
 295 #[cfg(feature = "std")]
 296 /// Utility to construct an invoice. Generally, unless you want to do something like a custom
 297 /// cltv_expiry, this is what you should be using to create an invoice. The reason being, this
 298 /// method stores the invoice's payment secret and preimage in `ChannelManager`, so (a) the user
 299 /// doesn't have to store preimage/payment secret information and (b) `ChannelManager` can verify
 300 /// that the payment secret is valid when the invoice is paid.
 301 ///
 302 /// `invoice_expiry_delta_secs` describes the number of seconds that the invoice is valid for
 303 /// in excess of the current time.
 304 ///
 305 /// You can specify a custom `min_final_cltv_expiry_delta`, or let LDK default it to
 306 /// [`MIN_FINAL_CLTV_EXPIRY_DELTA`]. The provided expiry must be at least [`MIN_FINAL_CLTV_EXPIRY_DELTA`].
 307 /// Note that LDK will add a buffer of 3 blocks to the delta to allow for up to a few new block
 308 /// confirmations during routing.
 309 ///
 310 /// [`MIN_FINAL_CLTV_EXPIRY_DETLA`]: lightning::ln::channelmanager::MIN_FINAL_CLTV_EXPIRY_DELTA
 311 pub fn create_invoice_from_channelmanager<M: Deref, T: Deref, ES: Deref, NS: Deref, SP: Deref, F: Deref, R: Deref, L: Deref>(
 312         channelmanager: &ChannelManager<M, T, ES, NS, SP, F, R, L>, node_signer: NS, logger: L,
 313         network: Currency, amt_msat: Option<u64>, description: String, invoice_expiry_delta_secs: u32,
 314         min_final_cltv_expiry_delta: Option<u16>,
 315 ) -> Result<Invoice, SignOrCreationError<()>>
 316 where
 317         M::Target: chain::Watch<<SP::Target as SignerProvider>::Signer>,
 318         T::Target: BroadcasterInterface,
 319         ES::Target: EntropySource,
 320         NS::Target: NodeSigner,
 321         SP::Target: SignerProvider,
 322         F::Target: FeeEstimator,
 323         R::Target: Router,
 324         L::Target: Logger,
 325 {
 326         use std::time::SystemTime;
 327         let duration = SystemTime::now().duration_since(SystemTime::UNIX_EPOCH)
 328                 .expect("for the foreseeable future this shouldn't happen");
 329         create_invoice_from_channelmanager_and_duration_since_epoch(
 330                 channelmanager, node_signer, logger, network, amt_msat,
 331                 description, duration, invoice_expiry_delta_secs, min_final_cltv_expiry_delta,
 332         )
 333 }
 334
 335 #[cfg(feature = "std")]
 336 /// Utility to construct an invoice. Generally, unless you want to do something like a custom
 337 /// cltv_expiry, this is what you should be using to create an invoice. The reason being, this
 338 /// method stores the invoice's payment secret and preimage in `ChannelManager`, so (a) the user
 339 /// doesn't have to store preimage/payment secret information and (b) `ChannelManager` can verify
 340 /// that the payment secret is valid when the invoice is paid.
 341 /// Use this variant if you want to pass the `description_hash` to the invoice.
 342 ///
 343 /// `invoice_expiry_delta_secs` describes the number of seconds that the invoice is valid for
 344 /// in excess of the current time.
 345 ///
 346 /// You can specify a custom `min_final_cltv_expiry_delta`, or let LDK default it to
 347 /// [`MIN_FINAL_CLTV_EXPIRY_DELTA`]. The provided expiry must be at least [`MIN_FINAL_CLTV_EXPIRY_DELTA`].
 348 /// Note that LDK will add a buffer of 3 blocks to the delta to allow for up to a few new block
 349 /// confirmations during routing.
 350 ///
 351 /// [`MIN_FINAL_CLTV_EXPIRY_DETLA`]: lightning::ln::channelmanager::MIN_FINAL_CLTV_EXPIRY_DELTA
 352 pub fn create_invoice_from_channelmanager_with_description_hash<M: Deref, T: Deref, ES: Deref, NS: Deref, SP: Deref, F: Deref, R: Deref, L: Deref>(
 353         channelmanager: &ChannelManager<M, T, ES, NS, SP, F, R, L>, node_signer: NS, logger: L,
 354         network: Currency, amt_msat: Option<u64>, description_hash: Sha256,
 355         invoice_expiry_delta_secs: u32, min_final_cltv_expiry_delta: Option<u16>,
 356 ) -> Result<Invoice, SignOrCreationError<()>>
 357 where
 358         M::Target: chain::Watch<<SP::Target as SignerProvider>::Signer>,
 359         T::Target: BroadcasterInterface,
 360         ES::Target: EntropySource,
 361         NS::Target: NodeSigner,
 362         SP::Target: SignerProvider,
 363         F::Target: FeeEstimator,
 364         R::Target: Router,
 365         L::Target: Logger,
 366 {
 367         use std::time::SystemTime;
 368
 369         let duration = SystemTime::now()
 370                 .duration_since(SystemTime::UNIX_EPOCH)
 371                 .expect("for the foreseeable future this shouldn't happen");
 372
 373         create_invoice_from_channelmanager_with_description_hash_and_duration_since_epoch(
 374                 channelmanager, node_signer, logger, network, amt_msat,
 375                 description_hash, duration, invoice_expiry_delta_secs, min_final_cltv_expiry_delta,
 376         )
 377 }
 378
 379 /// See [`create_invoice_from_channelmanager_with_description_hash`]
 380 /// This version can be used in a `no_std` environment, where [`std::time::SystemTime`] is not
 381 /// available and the current time is supplied by the caller.
 382 pub fn create_invoice_from_channelmanager_with_description_hash_and_duration_since_epoch<M: Deref, T: Deref, ES: Deref, NS: Deref, SP: Deref, F: Deref, R: Deref, L: Deref>(
 383         channelmanager: &ChannelManager<M, T, ES, NS, SP, F, R, L>, node_signer: NS, logger: L,
 384         network: Currency, amt_msat: Option<u64>, description_hash: Sha256,
 385         duration_since_epoch: Duration, invoice_expiry_delta_secs: u32, min_final_cltv_expiry_delta: Option<u16>,
 386 ) -> Result<Invoice, SignOrCreationError<()>>
 387                 where
 388                         M::Target: chain::Watch<<SP::Target as SignerProvider>::Signer>,
 389                         T::Target: BroadcasterInterface,
 390                         ES::Target: EntropySource,
 391                         NS::Target: NodeSigner,
 392                         SP::Target: SignerProvider,
 393                         F::Target: FeeEstimator,
 394                         R::Target: Router,
 395                         L::Target: Logger,
 396 {
 397         _create_invoice_from_channelmanager_and_duration_since_epoch(
 398                 channelmanager, node_signer, logger, network, amt_msat,
 399                 InvoiceDescription::Hash(&description_hash),
 400                 duration_since_epoch, invoice_expiry_delta_secs, min_final_cltv_expiry_delta,
 401         )
 402 }
 403
 404 /// See [`create_invoice_from_channelmanager`]
 405 /// This version can be used in a `no_std` environment, where [`std::time::SystemTime`] is not
 406 /// available and the current time is supplied by the caller.
 407 pub fn create_invoice_from_channelmanager_and_duration_since_epoch<M: Deref, T: Deref, ES: Deref, NS: Deref, SP: Deref, F: Deref, R: Deref, L: Deref>(
 408         channelmanager: &ChannelManager<M, T, ES, NS, SP, F, R, L>, node_signer: NS, logger: L,
 409         network: Currency, amt_msat: Option<u64>, description: String, duration_since_epoch: Duration,
 410         invoice_expiry_delta_secs: u32, min_final_cltv_expiry_delta: Option<u16>,
 411 ) -> Result<Invoice, SignOrCreationError<()>>
 412                 where
 413                         M::Target: chain::Watch<<SP::Target as SignerProvider>::Signer>,
 414                         T::Target: BroadcasterInterface,
 415                         ES::Target: EntropySource,
 416                         NS::Target: NodeSigner,
 417                         SP::Target: SignerProvider,
 418                         F::Target: FeeEstimator,
 419                         R::Target: Router,
 420                         L::Target: Logger,
 421 {
 422         _create_invoice_from_channelmanager_and_duration_since_epoch(
 423                 channelmanager, node_signer, logger, network, amt_msat,
 424                 InvoiceDescription::Direct(
 425                         &Description::new(description).map_err(SignOrCreationError::CreationError)?,
 426                 ),
 427                 duration_since_epoch, invoice_expiry_delta_secs, min_final_cltv_expiry_delta,
 428         )
 429 }
 430
 431 fn _create_invoice_from_channelmanager_and_duration_since_epoch<M: Deref, T: Deref, ES: Deref, NS: Deref, SP: Deref, F: Deref, R: Deref, L: Deref>(
 432         channelmanager: &ChannelManager<M, T, ES, NS, SP, F, R, L>, node_signer: NS, logger: L,
 433         network: Currency, amt_msat: Option<u64>, description: InvoiceDescription,
 434         duration_since_epoch: Duration, invoice_expiry_delta_secs: u32, min_final_cltv_expiry_delta: Option<u16>,
 435 ) -> Result<Invoice, SignOrCreationError<()>>
 436                 where
 437                         M::Target: chain::Watch<<SP::Target as SignerProvider>::Signer>,
 438                         T::Target: BroadcasterInterface,
 439                         ES::Target: EntropySource,
 440                         NS::Target: NodeSigner,
 441                         SP::Target: SignerProvider,
 442                         F::Target: FeeEstimator,
 443                         R::Target: Router,
 444                         L::Target: Logger,
 445 {
 446         if min_final_cltv_expiry_delta.is_some() && min_final_cltv_expiry_delta.unwrap().saturating_add(3) < MIN_FINAL_CLTV_EXPIRY_DELTA {
 447                 return Err(SignOrCreationError::CreationError(CreationError::MinFinalCltvExpiryDeltaTooShort));
 448         }
 449
 450         // `create_inbound_payment` only returns an error if the amount is greater than the total bitcoin
 451         // supply.
 452         let (payment_hash, payment_secret) = channelmanager
 453                 .create_inbound_payment(amt_msat, invoice_expiry_delta_secs, min_final_cltv_expiry_delta)
 454                 .map_err(|()| SignOrCreationError::CreationError(CreationError::InvalidAmount))?;
 455         _create_invoice_from_channelmanager_and_duration_since_epoch_with_payment_hash(
 456                 channelmanager, node_signer, logger, network, amt_msat, description, duration_since_epoch,
 457                 invoice_expiry_delta_secs, payment_hash, payment_secret, min_final_cltv_expiry_delta)
 458 }
 459
 460 /// See [`create_invoice_from_channelmanager_and_duration_since_epoch`]
 461 /// This version allows for providing a custom [`PaymentHash`] for the invoice.
 462 /// This may be useful if you're building an on-chain swap or involving another protocol where
 463 /// the payment hash is also involved outside the scope of lightning.
 464 pub fn create_invoice_from_channelmanager_and_duration_since_epoch_with_payment_hash<M: Deref, T: Deref, ES: Deref, NS: Deref, SP: Deref, F: Deref, R: Deref, L: Deref>(
 465         channelmanager: &ChannelManager<M, T, ES, NS, SP, F, R, L>, node_signer: NS, logger: L,
 466         network: Currency, amt_msat: Option<u64>, description: String, duration_since_epoch: Duration,
 467         invoice_expiry_delta_secs: u32, payment_hash: PaymentHash, min_final_cltv_expiry_delta: Option<u16>,
 468 ) -> Result<Invoice, SignOrCreationError<()>>
 469         where
 470                 M::Target: chain::Watch<<SP::Target as SignerProvider>::Signer>,
 471                 T::Target: BroadcasterInterface,
 472                 ES::Target: EntropySource,
 473                 NS::Target: NodeSigner,
 474                 SP::Target: SignerProvider,
 475                 F::Target: FeeEstimator,
 476                 R::Target: Router,
 477                 L::Target: Logger,
 478 {
 479         let payment_secret = channelmanager
 480                 .create_inbound_payment_for_hash(payment_hash, amt_msat, invoice_expiry_delta_secs,
 481                         min_final_cltv_expiry_delta)
 482                 .map_err(|()| SignOrCreationError::CreationError(CreationError::InvalidAmount))?;
 483         _create_invoice_from_channelmanager_and_duration_since_epoch_with_payment_hash(
 484                 channelmanager, node_signer, logger, network, amt_msat,
 485                 InvoiceDescription::Direct(
 486                         &Description::new(description).map_err(SignOrCreationError::CreationError)?,
 487                 ),
 488                 duration_since_epoch, invoice_expiry_delta_secs, payment_hash, payment_secret,
 489                 min_final_cltv_expiry_delta,
 490         )
 491 }
 492
 493 fn _create_invoice_from_channelmanager_and_duration_since_epoch_with_payment_hash<M: Deref, T: Deref, ES: Deref, NS: Deref, SP: Deref, F: Deref, R: Deref, L: Deref>(
 494         channelmanager: &ChannelManager<M, T, ES, NS, SP, F, R, L>, node_signer: NS, logger: L,
 495         network: Currency, amt_msat: Option<u64>, description: InvoiceDescription, duration_since_epoch: Duration,
 496         invoice_expiry_delta_secs: u32, payment_hash: PaymentHash, payment_secret: PaymentSecret,
 497         min_final_cltv_expiry_delta: Option<u16>,
 498 ) -> Result<Invoice, SignOrCreationError<()>>
 499         where
 500                 M::Target: chain::Watch<<SP::Target as SignerProvider>::Signer>,
 501                 T::Target: BroadcasterInterface,
 502                 ES::Target: EntropySource,
 503                 NS::Target: NodeSigner,
 504                 SP::Target: SignerProvider,
 505                 F::Target: FeeEstimator,
 506                 R::Target: Router,
 507                 L::Target: Logger,
 508 {
 509         let our_node_pubkey = channelmanager.get_our_node_id();
 510         let channels = channelmanager.list_channels();
 511
 512         if min_final_cltv_expiry_delta.is_some() && min_final_cltv_expiry_delta.unwrap().saturating_add(3) < MIN_FINAL_CLTV_EXPIRY_DELTA {
 513                 return Err(SignOrCreationError::CreationError(CreationError::MinFinalCltvExpiryDeltaTooShort));
 514         }
 515
 516         log_trace!(logger, "Creating invoice with payment hash {}", log_bytes!(payment_hash.0));
 517
 518         let invoice = match description {
 519                 InvoiceDescription::Direct(description) => {
 520                         InvoiceBuilder::new(network).description(description.0.clone())
 521                 }
 522                 InvoiceDescription::Hash(hash) => InvoiceBuilder::new(network).description_hash(hash.0),
 523         };
 524
 525         let mut invoice = invoice
 526                 .duration_since_epoch(duration_since_epoch)
 527                 .payee_pub_key(our_node_pubkey)
 528                 .payment_hash(Hash::from_slice(&payment_hash.0).unwrap())
 529                 .payment_secret(payment_secret)
 530                 .basic_mpp()
 531                 .min_final_cltv_expiry_delta(
 532                         // Add a buffer of 3 to the delta if present, otherwise use LDK's minimum.
 533                         min_final_cltv_expiry_delta.map(|x| x.saturating_add(3)).unwrap_or(MIN_FINAL_CLTV_EXPIRY_DELTA).into())
 534                 .expiry_time(Duration::from_secs(invoice_expiry_delta_secs.into()));
 535         if let Some(amt) = amt_msat {
 536                 invoice = invoice.amount_milli_satoshis(amt);
 537         }
 538
 539         let route_hints = sort_and_filter_channels(channels, amt_msat, &logger);
 540         for hint in route_hints {
 541                 invoice = invoice.private_route(hint);
 542         }
 543
 544         let raw_invoice = match invoice.build_raw() {
 545                 Ok(inv) => inv,
 546                 Err(e) => return Err(SignOrCreationError::CreationError(e))
 547         };
 548         let hrp_str = raw_invoice.hrp.to_string();
 549         let hrp_bytes = hrp_str.as_bytes();
 550         let data_without_signature = raw_invoice.data.to_base32();
 551         let signed_raw_invoice = raw_invoice.sign(|_| node_signer.sign_invoice(hrp_bytes, &data_without_signature, Recipient::Node));
 552         match signed_raw_invoice {
 553                 Ok(inv) => Ok(Invoice::from_signed(inv).unwrap()),
 554                 Err(e) => Err(SignOrCreationError::SignError(e))
 555         }
 556 }
 557
 558 /// Sorts and filters the `channels` for an invoice, and returns the corresponding `RouteHint`s to include
 559 /// in the invoice.
 560 ///
 561 /// The filtering is based on the following criteria:
 562 /// * Only one channel per counterparty node
 563 /// * If the counterparty has a channel that is above the `min_inbound_capacity_msat` + 10% scaling
 564 ///   factor (to allow some margin for change in inbound), select the channel with the lowest
 565 ///   inbound capacity that is above this threshold.
 566 /// * If no `min_inbound_capacity_msat` is specified, or the counterparty has no channels above the
 567 ///   minimum + 10% scaling factor, select the channel with the highest inbound capacity per counterparty.
 568 /// * Prefer channels with capacity at least `min_inbound_capacity_msat` and where the channel
 569 ///   `is_usable` (i.e. the peer is connected).
 570 /// * If any public channel exists, only public [`RouteHint`]s will be returned.
 571 /// * If any public, announced, channel exists (i.e. a channel with 7+ confs, to ensure the
 572 ///   announcement has had a chance to propagate), no [`RouteHint`]s will be returned, as the
 573 ///   sender is expected to find the path by looking at the public channels instead.
 574 /// * Limited to a total of 3 channels.
 575 /// * Sorted by lowest inbound capacity if an online channel with the minimum amount requested exists,
 576 ///   otherwise sort by highest inbound capacity to give the payment the best chance of succeeding.
 577 fn sort_and_filter_channels<L: Deref>(
 578         channels: Vec<ChannelDetails>, min_inbound_capacity_msat: Option<u64>, logger: &L
 579 ) -> Vec<RouteHint> where L::Target: Logger {
 580         let mut filtered_channels: HashMap<PublicKey, ChannelDetails> = HashMap::new();
 581         let min_inbound_capacity = min_inbound_capacity_msat.unwrap_or(0);
 582         let mut min_capacity_channel_exists = false;
 583         let mut online_channel_exists = false;
 584         let mut online_min_capacity_channel_exists = false;
 585         let mut has_pub_unconf_chan = false;
 586
 587         log_trace!(logger, "Considering {} channels for invoice route hints", channels.len());
 588         for channel in channels.into_iter().filter(|chan| chan.is_channel_ready) {
 589                 if channel.get_inbound_payment_scid().is_none() || channel.counterparty.forwarding_info.is_none() {
 590                         log_trace!(logger, "Ignoring channel {} for invoice route hints", log_bytes!(channel.channel_id));
 591                         continue;
 592                 }
 593
 594                 if channel.is_public {
 595                         if channel.confirmations.is_some() && channel.confirmations < Some(7) {
 596                                 // If we have a public channel, but it doesn't have enough confirmations to (yet)
 597                                 // be in the public network graph (and have gotten a chance to propagate), include
 598                                 // route hints but only for public channels to protect private channel privacy.
 599                                 has_pub_unconf_chan = true;
 600                         } else {
 601                                 // If any public channel exists, return no hints and let the sender
 602                                 // look at the public channels instead.
 603                                 log_trace!(logger, "Not including channels in invoice route hints on account of public channel {}",
 604                                         log_bytes!(channel.channel_id));
 605                                 return vec![]
 606                         }
 607                 }
 608
 609                 if channel.inbound_capacity_msat >= min_inbound_capacity {
 610                         if !min_capacity_channel_exists {
 611                                 log_trace!(logger, "Channel with enough inbound capacity exists for invoice route hints");
 612                                 min_capacity_channel_exists = true;
 613                         }
 614
 615                         if channel.is_usable {
 616                                 online_min_capacity_channel_exists = true;
 617                         }
 618                 }
 619
 620                 if channel.is_usable && !online_channel_exists {
 621                         log_trace!(logger, "Channel with connected peer exists for invoice route hints");
 622                         online_channel_exists = true;
 623                 }
 624
 625                 match filtered_channels.entry(channel.counterparty.node_id) {
 626                         hash_map::Entry::Occupied(mut entry) => {
 627                                 let current_max_capacity = entry.get().inbound_capacity_msat;
 628                                 // If this channel is public and the previous channel is not, ensure we replace the
 629                                 // previous channel to avoid announcing non-public channels.
 630                                 let new_now_public = channel.is_public && !entry.get().is_public;
 631                                 // Decide whether we prefer the currently selected channel with the node to the new one,
 632                                 // based on their inbound capacity.
 633                                 let prefer_current = prefer_current_channel(min_inbound_capacity_msat, current_max_capacity,
 634                                         channel.inbound_capacity_msat);
 635                                 // If the public-ness of the channel has not changed (in which case simply defer to
 636                                 // `new_now_public), and this channel has more desirable inbound than the incumbent,
 637                                 // prefer to include this channel.
 638                                 let new_channel_preferable = channel.is_public == entry.get().is_public && !prefer_current;
 639
 640                                 if new_now_public || new_channel_preferable {
 641                                         log_trace!(logger,
 642                                                 "Preferring counterparty {} channel {} (SCID {:?}, {} msats) over {} (SCID {:?}, {} msats) for invoice route hints",
 643                                                 log_pubkey!(channel.counterparty.node_id),
 644                                                 log_bytes!(channel.channel_id), channel.short_channel_id,
 645                                                 channel.inbound_capacity_msat,
 646                                                 log_bytes!(entry.get().channel_id), entry.get().short_channel_id,
 647                                                 current_max_capacity);
 648                                         entry.insert(channel);
 649                                 } else {
 650                                         log_trace!(logger,
 651                                                 "Preferring counterparty {} channel {} (SCID {:?}, {} msats) over {} (SCID {:?}, {} msats) for invoice route hints",
 652                                                 log_pubkey!(channel.counterparty.node_id),
 653                                                 log_bytes!(entry.get().channel_id), entry.get().short_channel_id,
 654                                                 current_max_capacity,
 655                                                 log_bytes!(channel.channel_id), channel.short_channel_id,
 656                                                 channel.inbound_capacity_msat);
 657                                 }
 658                         }
 659                         hash_map::Entry::Vacant(entry) => {
 660                                 entry.insert(channel);
 661                         }
 662                 }
 663         }
 664
 665         let route_hint_from_channel = |channel: ChannelDetails| {
 666                 let forwarding_info = channel.counterparty.forwarding_info.as_ref().unwrap();
 667                 RouteHint(vec![RouteHintHop {
 668                         src_node_id: channel.counterparty.node_id,
 669                         short_channel_id: channel.get_inbound_payment_scid().unwrap(),
 670                         fees: RoutingFees {
 671                                 base_msat: forwarding_info.fee_base_msat,
 672                                 proportional_millionths: forwarding_info.fee_proportional_millionths,
 673                         },
 674                         cltv_expiry_delta: forwarding_info.cltv_expiry_delta,
 675                         htlc_minimum_msat: channel.inbound_htlc_minimum_msat,
 676                         htlc_maximum_msat: channel.inbound_htlc_maximum_msat,}])
 677         };
 678         // If all channels are private, prefer to return route hints which have a higher capacity than
 679         // the payment value and where we're currently connected to the channel counterparty.
 680         // Even if we cannot satisfy both goals, always ensure we include *some* hints, preferring
 681         // those which meet at least one criteria.
 682         let mut eligible_channels = filtered_channels
 683                 .into_iter()
 684                 .map(|(_, channel)| channel)
 685                 .filter(|channel| {
 686                         let has_enough_capacity = channel.inbound_capacity_msat >= min_inbound_capacity;
 687                         let include_channel = if has_pub_unconf_chan {
 688                                 // If we have a public channel, but it doesn't have enough confirmations to (yet)
 689                                 // be in the public network graph (and have gotten a chance to propagate), include
 690                                 // route hints but only for public channels to protect private channel privacy.
 691                                 channel.is_public
 692                         } else if online_min_capacity_channel_exists {
 693                                 has_enough_capacity && channel.is_usable
 694                         } else if min_capacity_channel_exists && online_channel_exists {
 695                                 // If there are some online channels and some min_capacity channels, but no
 696                                 // online-and-min_capacity channels, just include the min capacity ones and ignore
 697                                 // online-ness.
 698                                 has_enough_capacity
 699                         } else if min_capacity_channel_exists {
 700                                 has_enough_capacity
 701                         } else if online_channel_exists {
 702                                 channel.is_usable
 703                         } else { true };
 704
 705                         if include_channel {
 706                                 log_trace!(logger, "Including channel {} in invoice route hints",
 707                                         log_bytes!(channel.channel_id));
 708                         } else if !has_enough_capacity {
 709                                 log_trace!(logger, "Ignoring channel {} without enough capacity for invoice route hints",
 710                                         log_bytes!(channel.channel_id));
 711                         } else {
 712                                 debug_assert!(!channel.is_usable || (has_pub_unconf_chan && !channel.is_public));
 713                                 log_trace!(logger, "Ignoring channel {} with disconnected peer",
 714                                         log_bytes!(channel.channel_id));
 715                         }
 716
 717                         include_channel
 718                 })
 719                 .collect::<Vec<ChannelDetails>>();
 720
 721                 eligible_channels.sort_unstable_by(|a, b| {
 722                         if online_min_capacity_channel_exists {
 723                                 a.inbound_capacity_msat.cmp(&b.inbound_capacity_msat)
 724                         } else {
 725                                 b.inbound_capacity_msat.cmp(&a.inbound_capacity_msat)
 726                         }});
 727                 eligible_channels.into_iter().take(3).map(route_hint_from_channel).collect::<Vec<RouteHint>>()
 728 }
 729
 730 /// prefer_current_channel chooses a channel to use for route hints between a currently selected and candidate
 731 /// channel based on the inbound capacity of each channel and the minimum inbound capacity requested for the hints,
 732 /// returning true if the current channel should be preferred over the candidate channel.
 733 /// * If no minimum amount is requested, the channel with the most inbound is chosen to maximize the chances that a
 734 ///   payment of any size will succeed.
 735 /// * If we have channels with inbound above our minimum requested inbound (plus a 10% scaling factor, expressed as a
 736 ///   percentage) then we choose the lowest inbound channel with above this amount. If we have sufficient inbound
 737 ///   channels, we don't want to deplete our larger channels with small payments (the off-chain version of "grinding
 738 ///   our change").
 739 /// * If no channel above our minimum amount exists, then we just prefer the channel with the most inbound to give
 740 ///   payments the best chance of succeeding in multiple parts.
 741 fn prefer_current_channel(min_inbound_capacity_msat: Option<u64>, current_channel: u64,
 742         candidate_channel: u64) -> bool {
 743
 744         // If no min amount is given for the hints, err of the side of caution and choose the largest channel inbound to
 745         // maximize chances of any payment succeeding.
 746         if min_inbound_capacity_msat.is_none() {
 747                 return current_channel > candidate_channel
 748         }
 749
 750         let scaled_min_inbound = min_inbound_capacity_msat.unwrap() * 110;
 751         let current_sufficient = current_channel * 100 >= scaled_min_inbound;
 752         let candidate_sufficient = candidate_channel * 100 >= scaled_min_inbound;
 753
 754         if current_sufficient && candidate_sufficient {
 755                 return current_channel < candidate_channel
 756         } else if current_sufficient {
 757                 return true
 758         } else if candidate_sufficient {
 759                 return false
 760         }
 761
 762         current_channel > candidate_channel
 763 }
 764
 765 #[cfg(test)]
 766 mod test {
 767         use core::time::Duration;
 768         use crate::{Currency, Description, InvoiceDescription, SignOrCreationError, CreationError};
 769         use bitcoin_hashes::{Hash, sha256};
 770         use bitcoin_hashes::sha256::Hash as Sha256;
 771         use lightning::sign::PhantomKeysManager;
 772         use lightning::events::{MessageSendEvent, MessageSendEventsProvider, Event};
 773         use lightning::ln::{PaymentPreimage, PaymentHash};
 774         use lightning::ln::channelmanager::{PhantomRouteHints, MIN_FINAL_CLTV_EXPIRY_DELTA, PaymentId, RecipientOnionFields, Retry};
 775         use lightning::ln::functional_test_utils::*;
 776         use lightning::ln::msgs::ChannelMessageHandler;
 777         use lightning::routing::router::{PaymentParameters, RouteParameters};
 778         use lightning::util::test_utils;
 779         use lightning::util::config::UserConfig;
 780         use crate::utils::create_invoice_from_channelmanager_and_duration_since_epoch;
 781         use std::collections::HashSet;
 782
 783         #[test]
 784         fn test_prefer_current_channel() {
 785                 // No minimum, prefer larger candidate channel.
 786                 assert_eq!(crate::utils::prefer_current_channel(None, 100, 200), false);
 787
 788                 // No minimum, prefer larger current channel.
 789                 assert_eq!(crate::utils::prefer_current_channel(None, 200, 100), true);
 790
 791                 // Minimum set, prefer current channel over minimum + buffer.
 792                 assert_eq!(crate::utils::prefer_current_channel(Some(100), 115, 100), true);
 793
 794                 // Minimum set, prefer candidate channel over minimum + buffer.
 795                 assert_eq!(crate::utils::prefer_current_channel(Some(100), 105, 125), false);
 796
 797                 // Minimum set, both channels sufficient, prefer smaller current channel.
 798                 assert_eq!(crate::utils::prefer_current_channel(Some(100), 115, 125), true);
 799
 800                 // Minimum set, both channels sufficient, prefer smaller candidate channel.
 801                 assert_eq!(crate::utils::prefer_current_channel(Some(100), 200, 160), false);
 802
 803                 // Minimum set, neither sufficient, prefer larger current channel.
 804                 assert_eq!(crate::utils::prefer_current_channel(Some(200), 100, 50), true);
 805
 806                 // Minimum set, neither sufficient, prefer larger candidate channel.
 807                 assert_eq!(crate::utils::prefer_current_channel(Some(200), 100, 150), false);
 808         }
 809
 810
 811         #[test]
 812         fn test_from_channelmanager() {
 813                 let chanmon_cfgs = create_chanmon_cfgs(2);
 814                 let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
 815                 let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
 816                 let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
 817                 create_unannounced_chan_between_nodes_with_value(&nodes, 0, 1, 100000, 10001);
 818                 let non_default_invoice_expiry_secs = 4200;
 819                 let invoice = create_invoice_from_channelmanager_and_duration_since_epoch(
 820                         nodes[1].node, nodes[1].keys_manager, nodes[1].logger, Currency::BitcoinTestnet,
 821                         Some(10_000), "test".to_string(), Duration::from_secs(1234567),
 822                         non_default_invoice_expiry_secs, None).unwrap();
 823                 assert_eq!(invoice.amount_pico_btc(), Some(100_000));
 824                 // If no `min_final_cltv_expiry_delta` is specified, then it should be `MIN_FINAL_CLTV_EXPIRY_DELTA`.
 825                 assert_eq!(invoice.min_final_cltv_expiry_delta(), MIN_FINAL_CLTV_EXPIRY_DELTA as u64);
 826                 assert_eq!(invoice.description(), InvoiceDescription::Direct(&Description("test".to_string())));
 827                 assert_eq!(invoice.expiry_time(), Duration::from_secs(non_default_invoice_expiry_secs.into()));
 828
 829                 // Invoice SCIDs should always use inbound SCID aliases over the real channel ID, if one is
 830                 // available.
 831                 let chan = &nodes[1].node.list_usable_channels()[0];
 832                 assert_eq!(invoice.route_hints().len(), 1);
 833                 assert_eq!(invoice.route_hints()[0].0.len(), 1);
 834                 assert_eq!(invoice.route_hints()[0].0[0].short_channel_id, chan.inbound_scid_alias.unwrap());
 835
 836                 assert_eq!(invoice.route_hints()[0].0[0].htlc_minimum_msat, chan.inbound_htlc_minimum_msat);
 837                 assert_eq!(invoice.route_hints()[0].0[0].htlc_maximum_msat, chan.inbound_htlc_maximum_msat);
 838
 839                 let payment_params = PaymentParameters::from_node_id(invoice.recover_payee_pub_key(),
 840                                 invoice.min_final_cltv_expiry_delta() as u32)
 841                         .with_bolt11_features(invoice.features().unwrap().clone()).unwrap()
 842                         .with_route_hints(invoice.route_hints()).unwrap();
 843                 let route_params = RouteParameters {
 844                         payment_params,
 845                         final_value_msat: invoice.amount_milli_satoshis().unwrap(),
 846                 };
 847                 let payment_event = {
 848                         let mut payment_hash = PaymentHash([0; 32]);
 849                         payment_hash.0.copy_from_slice(&invoice.payment_hash().as_ref()[0..32]);
 850                         nodes[0].node.send_payment(payment_hash,
 851                                 RecipientOnionFields::secret_only(*invoice.payment_secret()),
 852                                 PaymentId(payment_hash.0), route_params, Retry::Attempts(0)).unwrap();
 853                         let mut added_monitors = nodes[0].chain_monitor.added_monitors.lock().unwrap();
 854                         assert_eq!(added_monitors.len(), 1);
 855                         added_monitors.clear();
 856
 857                         let mut events = nodes[0].node.get_and_clear_pending_msg_events();
 858                         assert_eq!(events.len(), 1);
 859                         SendEvent::from_event(events.remove(0))
 860
 861                 };
 862                 nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &payment_event.msgs[0]);
 863                 nodes[1].node.handle_commitment_signed(&nodes[0].node.get_our_node_id(), &payment_event.commitment_msg);
 864                 let mut added_monitors = nodes[1].chain_monitor.added_monitors.lock().unwrap();
 865                 assert_eq!(added_monitors.len(), 1);
 866                 added_monitors.clear();
 867                 let events = nodes[1].node.get_and_clear_pending_msg_events();
 868                 assert_eq!(events.len(), 2);
 869         }
 870
 871         fn do_create_invoice_min_final_cltv_delta(with_custom_delta: bool) {
 872                 let chanmon_cfgs = create_chanmon_cfgs(2);
 873                 let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
 874                 let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
 875                 let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
 876                 let custom_min_final_cltv_expiry_delta = Some(50);
 877
 878                 let invoice = crate::utils::create_invoice_from_channelmanager_and_duration_since_epoch(
 879                         nodes[1].node, nodes[1].keys_manager, nodes[1].logger, Currency::BitcoinTestnet,
 880                         Some(10_000), "".into(), Duration::from_secs(1234567), 3600,
 881                         if with_custom_delta { custom_min_final_cltv_expiry_delta } else { None },
 882                 ).unwrap();
 883                 assert_eq!(invoice.min_final_cltv_expiry_delta(), if with_custom_delta {
 884                         custom_min_final_cltv_expiry_delta.unwrap() + 3 /* Buffer */} else { MIN_FINAL_CLTV_EXPIRY_DELTA } as u64);
 885         }
 886
 887         #[test]
 888         fn test_create_invoice_custom_min_final_cltv_delta() {
 889                 do_create_invoice_min_final_cltv_delta(true);
 890                 do_create_invoice_min_final_cltv_delta(false);
 891         }
 892
 893         #[test]
 894         fn create_invoice_min_final_cltv_delta_equals_htlc_fail_buffer() {
 895                 let chanmon_cfgs = create_chanmon_cfgs(2);
 896                 let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
 897                 let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
 898                 let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
 899                 let custom_min_final_cltv_expiry_delta = Some(21);
 900
 901                 let invoice = crate::utils::create_invoice_from_channelmanager_and_duration_since_epoch(
 902                         nodes[1].node, nodes[1].keys_manager, nodes[1].logger, Currency::BitcoinTestnet,
 903                         Some(10_000), "".into(), Duration::from_secs(1234567), 3600,
 904                         custom_min_final_cltv_expiry_delta,
 905                 ).unwrap();
 906                 assert_eq!(invoice.min_final_cltv_expiry_delta(), MIN_FINAL_CLTV_EXPIRY_DELTA as u64);
 907         }
 908
 909         #[test]
 910         fn test_create_invoice_with_description_hash() {
 911                 let chanmon_cfgs = create_chanmon_cfgs(2);
 912                 let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
 913                 let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
 914                 let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
 915                 let description_hash = crate::Sha256(Hash::hash("Testing description_hash".as_bytes()));
 916                 let invoice = crate::utils::create_invoice_from_channelmanager_with_description_hash_and_duration_since_epoch(
 917                         nodes[1].node, nodes[1].keys_manager, nodes[1].logger, Currency::BitcoinTestnet,
 918                         Some(10_000), description_hash, Duration::from_secs(1234567), 3600, None,
 919                 ).unwrap();
 920                 assert_eq!(invoice.amount_pico_btc(), Some(100_000));
 921                 assert_eq!(invoice.min_final_cltv_expiry_delta(), MIN_FINAL_CLTV_EXPIRY_DELTA as u64);
 922                 assert_eq!(invoice.description(), InvoiceDescription::Hash(&crate::Sha256(Sha256::hash("Testing description_hash".as_bytes()))));
 923         }
 924
 925         #[test]
 926         fn test_create_invoice_from_channelmanager_and_duration_since_epoch_with_payment_hash() {
 927                 let chanmon_cfgs = create_chanmon_cfgs(2);
 928                 let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
 929                 let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
 930                 let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
 931                 let payment_hash = PaymentHash([0; 32]);
 932                 let invoice = crate::utils::create_invoice_from_channelmanager_and_duration_since_epoch_with_payment_hash(
 933                         nodes[1].node, nodes[1].keys_manager, nodes[1].logger, Currency::BitcoinTestnet,
 934                         Some(10_000), "test".to_string(), Duration::from_secs(1234567), 3600,
 935                         payment_hash, None,
 936                 ).unwrap();
 937                 assert_eq!(invoice.amount_pico_btc(), Some(100_000));
 938                 assert_eq!(invoice.min_final_cltv_expiry_delta(), MIN_FINAL_CLTV_EXPIRY_DELTA as u64);
 939                 assert_eq!(invoice.description(), InvoiceDescription::Direct(&Description("test".to_string())));
 940                 assert_eq!(invoice.payment_hash(), &sha256::Hash::from_slice(&payment_hash.0[..]).unwrap());
 941         }
 942
 943         #[test]
 944         fn test_hints_has_only_public_confd_channels() {
 945                 let chanmon_cfgs = create_chanmon_cfgs(2);
 946                 let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
 947                 let mut config = test_default_channel_config();
 948                 config.channel_handshake_config.minimum_depth = 1;
 949                 let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[Some(config), Some(config)]);
 950                 let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
 951
 952                 // Create a private channel with lots of capacity and a lower value public channel (without
 953                 // confirming the funding tx yet).
 954                 let unannounced_scid = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 1, 10_000_000, 0);
 955                 let conf_tx = create_chan_between_nodes_with_value_init(&nodes[0], &nodes[1], 10_000, 0);
 956
 957                 // Before the channel is available, we should include the unannounced_scid.
 958                 let mut scid_aliases = HashSet::new();
 959                 scid_aliases.insert(unannounced_scid.0.short_channel_id_alias.unwrap());
 960                 match_invoice_routes(Some(5000), &nodes[1], scid_aliases.clone());
 961
 962                 // However after we mine the funding tx and exchange channel_ready messages for the public
 963                 // channel we'll immediately switch to including it as a route hint, even though it isn't
 964                 // yet announced.
 965                 let pub_channel_scid = mine_transaction(&nodes[0], &conf_tx);
 966                 let node_a_pub_channel_ready = get_event_msg!(nodes[0], MessageSendEvent::SendChannelReady, nodes[1].node.get_our_node_id());
 967                 nodes[1].node.handle_channel_ready(&nodes[0].node.get_our_node_id(), &node_a_pub_channel_ready);
 968
 969                 assert_eq!(mine_transaction(&nodes[1], &conf_tx), pub_channel_scid);
 970                 let events = nodes[1].node.get_and_clear_pending_msg_events();
 971                 assert_eq!(events.len(), 2);
 972                 if let MessageSendEvent::SendChannelReady { msg, .. } = &events[0] {
 973                         nodes[0].node.handle_channel_ready(&nodes[1].node.get_our_node_id(), msg);
 974                 } else { panic!(); }
 975                 if let MessageSendEvent::SendChannelUpdate { msg, .. } = &events[1] {
 976                         nodes[0].node.handle_channel_update(&nodes[1].node.get_our_node_id(), msg);
 977                 } else { panic!(); }
 978
 979                 nodes[1].node.handle_channel_update(&nodes[0].node.get_our_node_id(), &get_event_msg!(nodes[0], MessageSendEvent::SendChannelUpdate, nodes[1].node.get_our_node_id()));
 980
 981                 expect_channel_ready_event(&nodes[0], &nodes[1].node.get_our_node_id());
 982                 expect_channel_ready_event(&nodes[1], &nodes[0].node.get_our_node_id());
 983
 984                 scid_aliases.clear();
 985                 scid_aliases.insert(node_a_pub_channel_ready.short_channel_id_alias.unwrap());
 986                 match_invoice_routes(Some(5000), &nodes[1], scid_aliases.clone());
 987                 // This also applies even if the amount is more than the payment amount, to ensure users
 988                 // dont screw up their privacy.
 989                 match_invoice_routes(Some(50_000_000), &nodes[1], scid_aliases.clone());
 990
 991                 // The same remains true until the channel has 7 confirmations, at which point we include
 992                 // no hints.
 993                 connect_blocks(&nodes[1], 5);
 994                 match_invoice_routes(Some(5000), &nodes[1], scid_aliases.clone());
 995                 connect_blocks(&nodes[1], 1);
 996                 get_event_msg!(nodes[1], MessageSendEvent::SendAnnouncementSignatures, nodes[0].node.get_our_node_id());
 997                 match_invoice_routes(Some(5000), &nodes[1], HashSet::new());
 998         }
 999
1000         #[test]
1001         fn test_hints_includes_single_channels_to_nodes() {
1002                 let chanmon_cfgs = create_chanmon_cfgs(3);
1003                 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
1004                 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
1005                 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
1006
1007                 let chan_1_0 = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 0, 100000, 10001);
1008                 let chan_2_0 = create_unannounced_chan_between_nodes_with_value(&nodes, 2, 0, 100000, 10001);
1009
1010                 let mut scid_aliases = HashSet::new();
1011                 scid_aliases.insert(chan_1_0.0.short_channel_id_alias.unwrap());
1012                 scid_aliases.insert(chan_2_0.0.short_channel_id_alias.unwrap());
1013
1014                 match_invoice_routes(Some(5000), &nodes[0], scid_aliases);
1015         }
1016
1017         #[test]
1018         fn test_hints_has_only_lowest_inbound_capacity_channel_above_minimum() {
1019                 let chanmon_cfgs = create_chanmon_cfgs(2);
1020                 let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
1021                 let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
1022                 let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
1023
1024                 let _chan_1_0_inbound_below_amt = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 0, 10_000, 0);
1025                 let _chan_1_0_large_inbound_above_amt = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 0, 500_000, 0);
1026                 let chan_1_0_low_inbound_above_amt = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 0, 200_000, 0);
1027
1028                 let mut scid_aliases = HashSet::new();
1029                 scid_aliases.insert(chan_1_0_low_inbound_above_amt.0.short_channel_id_alias.unwrap());
1030                 match_invoice_routes(Some(100_000_000), &nodes[0], scid_aliases);
1031         }
1032
1033         #[test]
1034         fn test_hints_has_only_online_channels() {
1035                 let chanmon_cfgs = create_chanmon_cfgs(4);
1036                 let node_cfgs = create_node_cfgs(4, &chanmon_cfgs);
1037                 let node_chanmgrs = create_node_chanmgrs(4, &node_cfgs, &[None, None, None, None]);
1038                 let nodes = create_network(4, &node_cfgs, &node_chanmgrs);
1039                 let chan_a = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 0, 10_000_000, 0);
1040                 let chan_b = create_unannounced_chan_between_nodes_with_value(&nodes, 2, 0, 10_000_000, 0);
1041                 let _chan_c = create_unannounced_chan_between_nodes_with_value(&nodes, 3, 0, 1_000_000, 0);
1042
1043                 // With all peers connected we should get all hints that have sufficient value
1044                 let mut scid_aliases = HashSet::new();
1045                 scid_aliases.insert(chan_a.0.short_channel_id_alias.unwrap());
1046                 scid_aliases.insert(chan_b.0.short_channel_id_alias.unwrap());
1047
1048                 match_invoice_routes(Some(1_000_000_000), &nodes[0], scid_aliases.clone());
1049
1050                 // With only one sufficient-value peer connected we should only get its hint
1051                 scid_aliases.remove(&chan_b.0.short_channel_id_alias.unwrap());
1052                 nodes[0].node.peer_disconnected(&nodes[2].node.get_our_node_id());
1053                 match_invoice_routes(Some(1_000_000_000), &nodes[0], scid_aliases.clone());
1054
1055                 // If we don't have any sufficient-value peers connected we should get all hints with
1056                 // sufficient value, even though there is a connected insufficient-value peer.
1057                 scid_aliases.insert(chan_b.0.short_channel_id_alias.unwrap());
1058                 nodes[0].node.peer_disconnected(&nodes[1].node.get_our_node_id());
1059                 match_invoice_routes(Some(1_000_000_000), &nodes[0], scid_aliases);
1060         }
1061
1062         #[test]
1063         fn test_insufficient_inbound_sort_by_highest_capacity() {
1064                 let chanmon_cfgs = create_chanmon_cfgs(5);
1065                 let node_cfgs = create_node_cfgs(5, &chanmon_cfgs);
1066                 let node_chanmgrs = create_node_chanmgrs(5, &node_cfgs, &[None, None, None, None, None]);
1067                 let nodes = create_network(5, &node_cfgs, &node_chanmgrs);
1068                 let _chan_1_0 = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 0, 100_000, 0);
1069                 let chan_2_0 = create_unannounced_chan_between_nodes_with_value(&nodes, 2, 0, 200_000, 0);
1070                 let chan_3_0 = create_unannounced_chan_between_nodes_with_value(&nodes, 3, 0, 300_000, 0);
1071                 let chan_4_0 = create_unannounced_chan_between_nodes_with_value(&nodes, 4, 0, 400_000, 0);
1072
1073                 // When no single channel has enough inbound capacity for the payment, we expect the three
1074                 // highest inbound channels to be chosen.
1075                 let mut scid_aliases = HashSet::new();
1076                 scid_aliases.insert(chan_2_0.0.short_channel_id_alias.unwrap());
1077                 scid_aliases.insert(chan_3_0.0.short_channel_id_alias.unwrap());
1078                 scid_aliases.insert(chan_4_0.0.short_channel_id_alias.unwrap());
1079
1080                 match_invoice_routes(Some(1_000_000_000), &nodes[0], scid_aliases.clone());
1081         }
1082
1083         #[test]
1084         fn test_sufficient_inbound_sort_by_lowest_capacity() {
1085                 let chanmon_cfgs = create_chanmon_cfgs(5);
1086                 let node_cfgs = create_node_cfgs(5, &chanmon_cfgs);
1087                 let node_chanmgrs = create_node_chanmgrs(5, &node_cfgs, &[None, None, None, None, None]);
1088                 let nodes = create_network(5, &node_cfgs, &node_chanmgrs);
1089                 let chan_1_0 = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 0, 100_000, 0);
1090                 let chan_2_0 = create_unannounced_chan_between_nodes_with_value(&nodes, 2, 0, 200_000, 0);
1091                 let chan_3_0 = create_unannounced_chan_between_nodes_with_value(&nodes, 3, 0, 300_000, 0);
1092                 let _chan_4_0 = create_unannounced_chan_between_nodes_with_value(&nodes, 4, 0, 400_000, 0);
1093
1094                 // When we have channels that have sufficient inbound for the payment, test that we sort
1095                 // by lowest inbound capacity.
1096                 let mut scid_aliases = HashSet::new();
1097                 scid_aliases.insert(chan_1_0.0.short_channel_id_alias.unwrap());
1098                 scid_aliases.insert(chan_2_0.0.short_channel_id_alias.unwrap());
1099                 scid_aliases.insert(chan_3_0.0.short_channel_id_alias.unwrap());
1100
1101                 match_invoice_routes(Some(50_000_000), &nodes[0], scid_aliases.clone());
1102         }
1103
1104         #[test]
1105         fn test_forwarding_info_not_assigned_channel_excluded_from_hints() {
1106                 let chanmon_cfgs = create_chanmon_cfgs(3);
1107                 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
1108                 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
1109                 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
1110                 let chan_1_0 = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 0, 100000, 10001);
1111
1112                 // Create an unannonced channel between `nodes[2]` and `nodes[0]`, for which the
1113                 // `msgs::ChannelUpdate` is never handled for the node(s). As the `msgs::ChannelUpdate`
1114                 // is never handled, the `channel.counterparty.forwarding_info` is never assigned.
1115                 let mut private_chan_cfg = UserConfig::default();
1116                 private_chan_cfg.channel_handshake_config.announced_channel = false;
1117                 let temporary_channel_id = nodes[2].node.create_channel(nodes[0].node.get_our_node_id(), 1_000_000, 500_000_000, 42, Some(private_chan_cfg)).unwrap();
1118                 let open_channel = get_event_msg!(nodes[2], MessageSendEvent::SendOpenChannel, nodes[0].node.get_our_node_id());
1119                 nodes[0].node.handle_open_channel(&nodes[2].node.get_our_node_id(), &open_channel);
1120                 let accept_channel = get_event_msg!(nodes[0], MessageSendEvent::SendAcceptChannel, nodes[2].node.get_our_node_id());
1121                 nodes[2].node.handle_accept_channel(&nodes[0].node.get_our_node_id(), &accept_channel);
1122
1123                 let tx = sign_funding_transaction(&nodes[2], &nodes[0], 1_000_000, temporary_channel_id);
1124
1125                 let conf_height = core::cmp::max(nodes[2].best_block_info().1 + 1, nodes[0].best_block_info().1 + 1);
1126                 confirm_transaction_at(&nodes[2], &tx, conf_height);
1127                 connect_blocks(&nodes[2], CHAN_CONFIRM_DEPTH - 1);
1128                 confirm_transaction_at(&nodes[0], &tx, conf_height);
1129                 connect_blocks(&nodes[0], CHAN_CONFIRM_DEPTH - 1);
1130                 let as_channel_ready = get_event_msg!(nodes[2], MessageSendEvent::SendChannelReady, nodes[0].node.get_our_node_id());
1131                 nodes[2].node.handle_channel_ready(&nodes[0].node.get_our_node_id(), &get_event_msg!(nodes[0], MessageSendEvent::SendChannelReady, nodes[2].node.get_our_node_id()));
1132                 get_event_msg!(nodes[2], MessageSendEvent::SendChannelUpdate, nodes[0].node.get_our_node_id());
1133                 nodes[0].node.handle_channel_ready(&nodes[2].node.get_our_node_id(), &as_channel_ready);
1134                 get_event_msg!(nodes[0], MessageSendEvent::SendChannelUpdate, nodes[2].node.get_our_node_id());
1135                 expect_channel_ready_event(&nodes[0], &nodes[2].node.get_our_node_id());
1136                 expect_channel_ready_event(&nodes[2], &nodes[0].node.get_our_node_id());
1137
1138                 // As `msgs::ChannelUpdate` was never handled for the participating node(s) of the second
1139                 // channel, the channel will never be assigned any `counterparty.forwarding_info`.
1140                 // Therefore only `chan_1_0` should be included in the hints.
1141                 let mut scid_aliases = HashSet::new();
1142                 scid_aliases.insert(chan_1_0.0.short_channel_id_alias.unwrap());
1143                 match_invoice_routes(Some(5000), &nodes[0], scid_aliases);
1144         }
1145
1146         #[test]
1147         fn test_no_hints_if_a_mix_between_public_and_private_channel_exists() {
1148                 let chanmon_cfgs = create_chanmon_cfgs(3);
1149                 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
1150                 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
1151                 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
1152                 let _chan_1_0 = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 0, 100000, 10001);
1153
1154                 let chan_2_0 = create_announced_chan_between_nodes_with_value(&nodes, 2, 0, 100000, 10001);
1155                 nodes[2].node.handle_channel_update(&nodes[0].node.get_our_node_id(), &chan_2_0.1);
1156                 nodes[0].node.handle_channel_update(&nodes[2].node.get_our_node_id(), &chan_2_0.0);
1157
1158                 // Ensure that the invoice doesn't include any route hints for any of `nodes[0]` channels,
1159                 // even though all channels between `nodes[1]` and `nodes[0]` are private, as there is a
1160                 // public channel between `nodes[2]` and `nodes[0]`
1161                 match_invoice_routes(Some(5000), &nodes[0], HashSet::new());
1162         }
1163
1164         #[test]
1165         fn test_only_public_channels_includes_no_channels_in_hints() {
1166                 let chanmon_cfgs = create_chanmon_cfgs(3);
1167                 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
1168                 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
1169                 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
1170                 let chan_1_0 = create_announced_chan_between_nodes_with_value(&nodes, 1, 0, 100000, 10001);
1171                 nodes[0].node.handle_channel_update(&nodes[1].node.get_our_node_id(), &chan_1_0.0);
1172                 nodes[1].node.handle_channel_update(&nodes[0].node.get_our_node_id(), &chan_1_0.1);
1173
1174                 let chan_2_0 = create_announced_chan_between_nodes_with_value(&nodes, 2, 0, 100000, 10001);
1175                 nodes[2].node.handle_channel_update(&nodes[0].node.get_our_node_id(), &chan_2_0.1);
1176                 nodes[0].node.handle_channel_update(&nodes[2].node.get_our_node_id(), &chan_2_0.0);
1177
1178                 // As all of `nodes[0]` channels are public, no channels should be included in the hints
1179                 match_invoice_routes(Some(5000), &nodes[0], HashSet::new());
1180         }
1181
1182         #[test]
1183         fn test_channels_with_lower_inbound_capacity_than_invoice_amt_hints_filtering() {
1184                 let chanmon_cfgs = create_chanmon_cfgs(3);
1185                 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
1186                 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
1187                 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
1188                 let chan_1_0 = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 0, 100_000, 0);
1189                 let chan_2_0 = create_unannounced_chan_between_nodes_with_value(&nodes, 2, 0, 1_000_000, 0);
1190
1191                 // As the invoice amt is 1 msat above chan_1_0's inbound capacity, it shouldn't be included
1192                 let mut scid_aliases_99_000_001_msat = HashSet::new();
1193                 scid_aliases_99_000_001_msat.insert(chan_2_0.0.short_channel_id_alias.unwrap());
1194
1195                 match_invoice_routes(Some(99_000_001), &nodes[0], scid_aliases_99_000_001_msat);
1196
1197                 // As the invoice amt is exactly at chan_1_0's inbound capacity, it should be included
1198                 let mut scid_aliases_99_000_000_msat = HashSet::new();
1199                 scid_aliases_99_000_000_msat.insert(chan_1_0.0.short_channel_id_alias.unwrap());
1200                 scid_aliases_99_000_000_msat.insert(chan_2_0.0.short_channel_id_alias.unwrap());
1201
1202                 match_invoice_routes(Some(99_000_000), &nodes[0], scid_aliases_99_000_000_msat);
1203
1204                 // As the invoice amt is above all channels' inbound capacity, they will still be included
1205                 let mut scid_aliases_2_000_000_000_msat = HashSet::new();
1206                 scid_aliases_2_000_000_000_msat.insert(chan_1_0.0.short_channel_id_alias.unwrap());
1207                 scid_aliases_2_000_000_000_msat.insert(chan_2_0.0.short_channel_id_alias.unwrap());
1208
1209                 match_invoice_routes(Some(2_000_000_000), &nodes[0], scid_aliases_2_000_000_000_msat);
1210
1211                 // An invoice with no specified amount should include all channels in the route hints.
1212                 let mut scid_aliases_no_specified_amount = HashSet::new();
1213                 scid_aliases_no_specified_amount.insert(chan_1_0.0.short_channel_id_alias.unwrap());
1214                 scid_aliases_no_specified_amount.insert(chan_2_0.0.short_channel_id_alias.unwrap());
1215
1216                 match_invoice_routes(None, &nodes[0], scid_aliases_no_specified_amount);
1217         }
1218
1219         fn match_invoice_routes<'a, 'b: 'a, 'c: 'b>(
1220                 invoice_amt: Option<u64>,
1221                 invoice_node: &Node<'a, 'b, 'c>,
1222                 mut chan_ids_to_match: HashSet<u64>
1223         ) {
1224                 let invoice = create_invoice_from_channelmanager_and_duration_since_epoch(
1225                         invoice_node.node, invoice_node.keys_manager, invoice_node.logger,
1226                         Currency::BitcoinTestnet, invoice_amt, "test".to_string(), Duration::from_secs(1234567),
1227                         3600, None).unwrap();
1228                 let hints = invoice.private_routes();
1229
1230                 for hint in hints {
1231                         let hint_short_chan_id = (hint.0).0[0].short_channel_id;
1232                         assert!(chan_ids_to_match.remove(&hint_short_chan_id));
1233                 }
1234                 assert!(chan_ids_to_match.is_empty(), "Unmatched short channel ids: {:?}", chan_ids_to_match);
1235         }
1236
1237         #[test]
1238         #[cfg(feature = "std")]
1239         fn test_multi_node_receive() {
1240                 do_test_multi_node_receive(true);
1241                 do_test_multi_node_receive(false);
1242         }
1243
1244         #[cfg(feature = "std")]
1245         fn do_test_multi_node_receive(user_generated_pmt_hash: bool) {
1246                 let mut chanmon_cfgs = create_chanmon_cfgs(3);
1247                 let seed_1 = [42u8; 32];
1248                 let seed_2 = [43u8; 32];
1249                 let cross_node_seed = [44u8; 32];
1250                 chanmon_cfgs[1].keys_manager.backing = PhantomKeysManager::new(&seed_1, 43, 44, &cross_node_seed);
1251                 chanmon_cfgs[2].keys_manager.backing = PhantomKeysManager::new(&seed_2, 43, 44, &cross_node_seed);
1252                 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
1253                 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
1254                 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
1255                 let chan_0_1 = create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 100000, 10001);
1256                 nodes[0].node.handle_channel_update(&nodes[1].node.get_our_node_id(), &chan_0_1.1);
1257                 nodes[1].node.handle_channel_update(&nodes[0].node.get_our_node_id(), &chan_0_1.0);
1258                 let chan_0_2 = create_announced_chan_between_nodes_with_value(&nodes, 0, 2, 100000, 10001);
1259                 nodes[0].node.handle_channel_update(&nodes[2].node.get_our_node_id(), &chan_0_2.1);
1260                 nodes[2].node.handle_channel_update(&nodes[0].node.get_our_node_id(), &chan_0_2.0);
1261
1262                 let payment_amt = 10_000;
1263                 let route_hints = vec![
1264                         nodes[1].node.get_phantom_route_hints(),
1265                         nodes[2].node.get_phantom_route_hints(),
1266                 ];
1267
1268                 let user_payment_preimage = PaymentPreimage([1; 32]);
1269                 let payment_hash = if user_generated_pmt_hash {
1270                         Some(PaymentHash(Sha256::hash(&user_payment_preimage.0[..]).into_inner()))
1271                 } else {
1272                         None
1273                 };
1274                 let non_default_invoice_expiry_secs = 4200;
1275
1276                 let invoice =
1277                         crate::utils::create_phantom_invoice::<&test_utils::TestKeysInterface, &test_utils::TestKeysInterface, &test_utils::TestLogger>(
1278                                 Some(payment_amt), payment_hash, "test".to_string(), non_default_invoice_expiry_secs,
1279                                 route_hints, nodes[1].keys_manager, nodes[1].keys_manager, nodes[1].logger,
1280                                 Currency::BitcoinTestnet, None, Duration::from_secs(1234567)
1281                         ).unwrap();
1282                 let (payment_hash, payment_secret) = (PaymentHash(invoice.payment_hash().into_inner()), *invoice.payment_secret());
1283                 let payment_preimage = if user_generated_pmt_hash {
1284                         user_payment_preimage
1285                 } else {
1286                         nodes[1].node.get_payment_preimage(payment_hash, payment_secret).unwrap()
1287                 };
1288
1289                 assert_eq!(invoice.min_final_cltv_expiry_delta(), MIN_FINAL_CLTV_EXPIRY_DELTA as u64);
1290                 assert_eq!(invoice.description(), InvoiceDescription::Direct(&Description("test".to_string())));
1291                 assert_eq!(invoice.route_hints().len(), 2);
1292                 assert_eq!(invoice.expiry_time(), Duration::from_secs(non_default_invoice_expiry_secs.into()));
1293                 assert!(!invoice.features().unwrap().supports_basic_mpp());
1294
1295                 let payment_params = PaymentParameters::from_node_id(invoice.recover_payee_pub_key(),
1296                                 invoice.min_final_cltv_expiry_delta() as u32)
1297                         .with_bolt11_features(invoice.features().unwrap().clone()).unwrap()
1298                         .with_route_hints(invoice.route_hints()).unwrap();
1299                 let params = RouteParameters {
1300                         payment_params,
1301                         final_value_msat: invoice.amount_milli_satoshis().unwrap(),
1302                 };
1303                 let (payment_event, fwd_idx) = {
1304                         let mut payment_hash = PaymentHash([0; 32]);
1305                         payment_hash.0.copy_from_slice(&invoice.payment_hash().as_ref()[0..32]);
1306                         nodes[0].node.send_payment(payment_hash,
1307                                 RecipientOnionFields::secret_only(*invoice.payment_secret()),
1308                                 PaymentId(payment_hash.0), params, Retry::Attempts(0)).unwrap();
1309                         let mut added_monitors = nodes[0].chain_monitor.added_monitors.lock().unwrap();
1310                         assert_eq!(added_monitors.len(), 1);
1311                         added_monitors.clear();
1312
1313                         let mut events = nodes[0].node.get_and_clear_pending_msg_events();
1314                         assert_eq!(events.len(), 1);
1315                         let fwd_idx = match events[0] {
1316                                 MessageSendEvent::UpdateHTLCs { node_id, .. } => {
1317                                         if node_id == nodes[1].node.get_our_node_id() {
1318                                                 1
1319                                         } else { 2 }
1320                                 },
1321                                 _ => panic!("Unexpected event")
1322                         };
1323                         (SendEvent::from_event(events.remove(0)), fwd_idx)
1324                 };
1325                 nodes[fwd_idx].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &payment_event.msgs[0]);
1326                 commitment_signed_dance!(nodes[fwd_idx], nodes[0], &payment_event.commitment_msg, false, true);
1327
1328                 // Note that we have to "forward pending HTLCs" twice before we see the PaymentClaimable as
1329                 // this "emulates" the payment taking two hops, providing some privacy to make phantom node
1330                 // payments "look real" by taking more time.
1331                 expect_pending_htlcs_forwardable_ignore!(nodes[fwd_idx]);
1332                 nodes[fwd_idx].node.process_pending_htlc_forwards();
1333                 expect_pending_htlcs_forwardable_ignore!(nodes[fwd_idx]);
1334                 nodes[fwd_idx].node.process_pending_htlc_forwards();
1335
1336                 let payment_preimage_opt = if user_generated_pmt_hash { None } else { Some(payment_preimage) };
1337                 expect_payment_claimable!(&nodes[fwd_idx], payment_hash, payment_secret, payment_amt, payment_preimage_opt, invoice.recover_payee_pub_key());
1338                 do_claim_payment_along_route(&nodes[0], &[&vec!(&nodes[fwd_idx])[..]], false, payment_preimage);
1339                 let events = nodes[0].node.get_and_clear_pending_events();
1340                 assert_eq!(events.len(), 2);
1341                 match events[0] {
1342                         Event::PaymentSent { payment_preimage: ref ev_preimage, payment_hash: ref ev_hash, ref fee_paid_msat, .. } => {
1343                                 assert_eq!(payment_preimage, *ev_preimage);
1344                                 assert_eq!(payment_hash, *ev_hash);
1345                                 assert_eq!(fee_paid_msat, &Some(0));
1346                         },
1347                         _ => panic!("Unexpected event")
1348                 }
1349                 match events[1] {
1350                         Event::PaymentPathSuccessful { payment_hash: hash, .. } => {
1351                                 assert_eq!(hash, Some(payment_hash));
1352                         },
1353                         _ => panic!("Unexpected event")
1354                 }
1355         }
1356
1357         #[test]
1358         #[cfg(feature = "std")]
1359         fn test_multi_node_hints_has_htlc_min_max_values() {
1360                 let mut chanmon_cfgs = create_chanmon_cfgs(3);
1361                 let seed_1 = [42u8; 32];
1362                 let seed_2 = [43u8; 32];
1363                 let cross_node_seed = [44u8; 32];
1364                 chanmon_cfgs[1].keys_manager.backing = PhantomKeysManager::new(&seed_1, 43, 44, &cross_node_seed);
1365                 chanmon_cfgs[2].keys_manager.backing = PhantomKeysManager::new(&seed_2, 43, 44, &cross_node_seed);
1366                 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
1367                 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
1368                 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
1369
1370                 create_unannounced_chan_between_nodes_with_value(&nodes, 0, 1, 100000, 10001);
1371                 create_unannounced_chan_between_nodes_with_value(&nodes, 0, 2, 100000, 10001);
1372
1373                 let payment_amt = 20_000;
1374                 let (payment_hash, _payment_secret) = nodes[1].node.create_inbound_payment(Some(payment_amt), 3600, None).unwrap();
1375                 let route_hints = vec![
1376                         nodes[1].node.get_phantom_route_hints(),
1377                         nodes[2].node.get_phantom_route_hints(),
1378                 ];
1379
1380                 let invoice = crate::utils::create_phantom_invoice::<&test_utils::TestKeysInterface,
1381                         &test_utils::TestKeysInterface, &test_utils::TestLogger>(Some(payment_amt), Some(payment_hash),
1382                                 "test".to_string(), 3600, route_hints, nodes[1].keys_manager, nodes[1].keys_manager,
1383                                 nodes[1].logger, Currency::BitcoinTestnet, None, Duration::from_secs(1234567)).unwrap();
1384
1385                 let chan_0_1 = &nodes[1].node.list_usable_channels()[0];
1386                 assert_eq!(invoice.route_hints()[0].0[0].htlc_minimum_msat, chan_0_1.inbound_htlc_minimum_msat);
1387                 assert_eq!(invoice.route_hints()[0].0[0].htlc_maximum_msat, chan_0_1.inbound_htlc_maximum_msat);
1388
1389                 let chan_0_2 = &nodes[2].node.list_usable_channels()[0];
1390                 assert_eq!(invoice.route_hints()[1].0[0].htlc_minimum_msat, chan_0_2.inbound_htlc_minimum_msat);
1391                 assert_eq!(invoice.route_hints()[1].0[0].htlc_maximum_msat, chan_0_2.inbound_htlc_maximum_msat);
1392         }
1393
1394         #[test]
1395         #[cfg(feature = "std")]
1396         fn create_phantom_invoice_with_description_hash() {
1397                 let chanmon_cfgs = create_chanmon_cfgs(3);
1398                 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
1399                 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
1400                 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
1401
1402                 let payment_amt = 20_000;
1403                 let route_hints = vec![
1404                         nodes[1].node.get_phantom_route_hints(),
1405                         nodes[2].node.get_phantom_route_hints(),
1406                 ];
1407
1408                 let description_hash = crate::Sha256(Hash::hash("Description hash phantom invoice".as_bytes()));
1409                 let non_default_invoice_expiry_secs = 4200;
1410                 let invoice = crate::utils::create_phantom_invoice_with_description_hash::<
1411                         &test_utils::TestKeysInterface, &test_utils::TestKeysInterface, &test_utils::TestLogger,
1412                 >(
1413                         Some(payment_amt), None, non_default_invoice_expiry_secs, description_hash,
1414                         route_hints, nodes[1].keys_manager, nodes[1].keys_manager, nodes[1].logger,
1415                         Currency::BitcoinTestnet, None, Duration::from_secs(1234567),
1416                 )
1417                 .unwrap();
1418                 assert_eq!(invoice.amount_pico_btc(), Some(200_000));
1419                 assert_eq!(invoice.min_final_cltv_expiry_delta(), MIN_FINAL_CLTV_EXPIRY_DELTA as u64);
1420                 assert_eq!(invoice.expiry_time(), Duration::from_secs(non_default_invoice_expiry_secs.into()));
1421                 assert_eq!(invoice.description(), InvoiceDescription::Hash(&crate::Sha256(Sha256::hash("Description hash phantom invoice".as_bytes()))));
1422         }
1423
1424         #[test]
1425         #[cfg(feature = "std")]
1426         fn create_phantom_invoice_with_custom_payment_hash_and_custom_min_final_cltv_delta() {
1427                 let chanmon_cfgs = create_chanmon_cfgs(3);
1428                 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
1429                 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
1430                 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
1431
1432                 let payment_amt = 20_000;
1433                 let route_hints = vec![
1434                         nodes[1].node.get_phantom_route_hints(),
1435                         nodes[2].node.get_phantom_route_hints(),
1436                 ];
1437                 let user_payment_preimage = PaymentPreimage([1; 32]);
1438                 let payment_hash = Some(PaymentHash(Sha256::hash(&user_payment_preimage.0[..]).into_inner()));
1439                 let non_default_invoice_expiry_secs = 4200;
1440                 let min_final_cltv_expiry_delta = Some(100);
1441                 let duration_since_epoch = Duration::from_secs(1234567);
1442                 let invoice = crate::utils::create_phantom_invoice::<&test_utils::TestKeysInterface,
1443                         &test_utils::TestKeysInterface, &test_utils::TestLogger>(Some(payment_amt), payment_hash,
1444                                 "".to_string(), non_default_invoice_expiry_secs, route_hints, nodes[1].keys_manager, nodes[1].keys_manager,
1445                                 nodes[1].logger, Currency::BitcoinTestnet, min_final_cltv_expiry_delta, duration_since_epoch).unwrap();
1446                 assert_eq!(invoice.amount_pico_btc(), Some(200_000));
1447                 assert_eq!(invoice.min_final_cltv_expiry_delta(), (min_final_cltv_expiry_delta.unwrap() + 3) as u64);
1448                 assert_eq!(invoice.expiry_time(), Duration::from_secs(non_default_invoice_expiry_secs.into()));
1449         }
1450
1451         #[test]
1452         #[cfg(feature = "std")]
1453         fn test_multi_node_hints_includes_single_channels_to_participating_nodes() {
1454                 let mut chanmon_cfgs = create_chanmon_cfgs(3);
1455                 let seed_1 = [42u8; 32];
1456                 let seed_2 = [43u8; 32];
1457                 let cross_node_seed = [44u8; 32];
1458                 chanmon_cfgs[1].keys_manager.backing = PhantomKeysManager::new(&seed_1, 43, 44, &cross_node_seed);
1459                 chanmon_cfgs[2].keys_manager.backing = PhantomKeysManager::new(&seed_2, 43, 44, &cross_node_seed);
1460                 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
1461                 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
1462                 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
1463
1464                 let chan_0_1 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 1, 100000, 10001);
1465                 let chan_0_2 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 2, 100000, 10001);
1466
1467                 let mut scid_aliases = HashSet::new();
1468                 scid_aliases.insert(chan_0_1.0.short_channel_id_alias.unwrap());
1469                 scid_aliases.insert(chan_0_2.0.short_channel_id_alias.unwrap());
1470
1471                 match_multi_node_invoice_routes(
1472                         Some(10_000),
1473                         &nodes[1],
1474                         vec![&nodes[1], &nodes[2],],
1475                         scid_aliases,
1476                         false
1477                 );
1478         }
1479
1480         #[test]
1481         #[cfg(feature = "std")]
1482         fn test_multi_node_hints_includes_one_channel_of_each_counterparty_nodes_per_participating_node() {
1483                 let mut chanmon_cfgs = create_chanmon_cfgs(4);
1484                 let seed_1 = [42u8; 32];
1485                 let seed_2 = [43u8; 32];
1486                 let cross_node_seed = [44u8; 32];
1487                 chanmon_cfgs[2].keys_manager.backing = PhantomKeysManager::new(&seed_1, 43, 44, &cross_node_seed);
1488                 chanmon_cfgs[3].keys_manager.backing = PhantomKeysManager::new(&seed_2, 43, 44, &cross_node_seed);
1489                 let node_cfgs = create_node_cfgs(4, &chanmon_cfgs);
1490                 let node_chanmgrs = create_node_chanmgrs(4, &node_cfgs, &[None, None, None, None]);
1491                 let nodes = create_network(4, &node_cfgs, &node_chanmgrs);
1492
1493                 let chan_0_2 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 2, 100000, 10001);
1494                 let chan_0_3 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 3, 1000000, 10001);
1495                 let chan_1_3 = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 3, 3_000_000, 10005);
1496
1497                 let mut scid_aliases = HashSet::new();
1498                 scid_aliases.insert(chan_0_2.0.short_channel_id_alias.unwrap());
1499                 scid_aliases.insert(chan_0_3.0.short_channel_id_alias.unwrap());
1500                 scid_aliases.insert(chan_1_3.0.short_channel_id_alias.unwrap());
1501
1502                 match_multi_node_invoice_routes(
1503                         Some(10_000),
1504                         &nodes[2],
1505                         vec![&nodes[2], &nodes[3],],
1506                         scid_aliases,
1507                         false
1508                 );
1509         }
1510
1511         #[test]
1512         #[cfg(feature = "std")]
1513         fn test_multi_node_forwarding_info_not_assigned_channel_excluded_from_hints() {
1514                 let mut chanmon_cfgs = create_chanmon_cfgs(4);
1515                 let seed_1 = [42u8; 32];
1516                 let seed_2 = [43u8; 32];
1517                 let cross_node_seed = [44u8; 32];
1518                 chanmon_cfgs[2].keys_manager.backing = PhantomKeysManager::new(&seed_1, 43, 44, &cross_node_seed);
1519                 chanmon_cfgs[3].keys_manager.backing = PhantomKeysManager::new(&seed_2, 43, 44, &cross_node_seed);
1520                 let node_cfgs = create_node_cfgs(4, &chanmon_cfgs);
1521                 let node_chanmgrs = create_node_chanmgrs(4, &node_cfgs, &[None, None, None, None]);
1522                 let nodes = create_network(4, &node_cfgs, &node_chanmgrs);
1523
1524                 let chan_0_2 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 2, 100000, 10001);
1525                 let chan_0_3 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 3, 1000000, 10001);
1526
1527                 // Create an unannonced channel between `nodes[1]` and `nodes[3]`, for which the
1528                 // `msgs::ChannelUpdate` is never handled for the node(s). As the `msgs::ChannelUpdate`
1529                 // is never handled, the `channel.counterparty.forwarding_info` is never assigned.
1530                 let mut private_chan_cfg = UserConfig::default();
1531                 private_chan_cfg.channel_handshake_config.announced_channel = false;
1532                 let temporary_channel_id = nodes[1].node.create_channel(nodes[3].node.get_our_node_id(), 1_000_000, 500_000_000, 42, Some(private_chan_cfg)).unwrap();
1533                 let open_channel = get_event_msg!(nodes[1], MessageSendEvent::SendOpenChannel, nodes[3].node.get_our_node_id());
1534                 nodes[3].node.handle_open_channel(&nodes[1].node.get_our_node_id(), &open_channel);
1535                 let accept_channel = get_event_msg!(nodes[3], MessageSendEvent::SendAcceptChannel, nodes[1].node.get_our_node_id());
1536                 nodes[1].node.handle_accept_channel(&nodes[3].node.get_our_node_id(), &accept_channel);
1537
1538                 let tx = sign_funding_transaction(&nodes[1], &nodes[3], 1_000_000, temporary_channel_id);
1539
1540                 let conf_height = core::cmp::max(nodes[1].best_block_info().1 + 1, nodes[3].best_block_info().1 + 1);
1541                 confirm_transaction_at(&nodes[1], &tx, conf_height);
1542                 connect_blocks(&nodes[1], CHAN_CONFIRM_DEPTH - 1);
1543                 confirm_transaction_at(&nodes[3], &tx, conf_height);
1544                 connect_blocks(&nodes[3], CHAN_CONFIRM_DEPTH - 1);
1545                 let as_channel_ready = get_event_msg!(nodes[1], MessageSendEvent::SendChannelReady, nodes[3].node.get_our_node_id());
1546                 nodes[1].node.handle_channel_ready(&nodes[3].node.get_our_node_id(), &get_event_msg!(nodes[3], MessageSendEvent::SendChannelReady, nodes[1].node.get_our_node_id()));
1547                 get_event_msg!(nodes[1], MessageSendEvent::SendChannelUpdate, nodes[3].node.get_our_node_id());
1548                 nodes[3].node.handle_channel_ready(&nodes[1].node.get_our_node_id(), &as_channel_ready);
1549                 get_event_msg!(nodes[3], MessageSendEvent::SendChannelUpdate, nodes[1].node.get_our_node_id());
1550                 expect_channel_ready_event(&nodes[1], &nodes[3].node.get_our_node_id());
1551                 expect_channel_ready_event(&nodes[3], &nodes[1].node.get_our_node_id());
1552
1553                 // As `msgs::ChannelUpdate` was never handled for the participating node(s) of the third
1554                 // channel, the channel will never be assigned any `counterparty.forwarding_info`.
1555                 // Therefore only `chan_0_3` should be included in the hints for `nodes[3]`.
1556                 let mut scid_aliases = HashSet::new();
1557                 scid_aliases.insert(chan_0_2.0.short_channel_id_alias.unwrap());
1558                 scid_aliases.insert(chan_0_3.0.short_channel_id_alias.unwrap());
1559
1560                 match_multi_node_invoice_routes(
1561                         Some(10_000),
1562                         &nodes[2],
1563                         vec![&nodes[2], &nodes[3],],
1564                         scid_aliases,
1565                         false
1566                 );
1567         }
1568
1569         #[test]
1570         #[cfg(feature = "std")]
1571         fn test_multi_node_with_only_public_channels_hints_includes_only_phantom_route() {
1572                 let mut chanmon_cfgs = create_chanmon_cfgs(3);
1573                 let seed_1 = [42u8; 32];
1574                 let seed_2 = [43u8; 32];
1575                 let cross_node_seed = [44u8; 32];
1576                 chanmon_cfgs[1].keys_manager.backing = PhantomKeysManager::new(&seed_1, 43, 44, &cross_node_seed);
1577                 chanmon_cfgs[2].keys_manager.backing = PhantomKeysManager::new(&seed_2, 43, 44, &cross_node_seed);
1578                 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
1579                 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
1580                 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
1581
1582                 let chan_0_1 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 1, 100000, 10001);
1583
1584                 let chan_2_0 = create_announced_chan_between_nodes_with_value(&nodes, 2, 0, 100000, 10001);
1585                 nodes[2].node.handle_channel_update(&nodes[0].node.get_our_node_id(), &chan_2_0.1);
1586                 nodes[0].node.handle_channel_update(&nodes[2].node.get_our_node_id(), &chan_2_0.0);
1587
1588                 // Hints should include `chan_0_1` from as `nodes[1]` only have private channels, but not
1589                 // `chan_0_2` as `nodes[2]` only has public channels.
1590                 let mut scid_aliases = HashSet::new();
1591                 scid_aliases.insert(chan_0_1.0.short_channel_id_alias.unwrap());
1592
1593                 match_multi_node_invoice_routes(
1594                         Some(10_000),
1595                         &nodes[1],
1596                         vec![&nodes[1], &nodes[2],],
1597                         scid_aliases,
1598                         true
1599                 );
1600         }
1601
1602         #[test]
1603         #[cfg(feature = "std")]
1604         fn test_multi_node_with_mixed_public_and_private_channel_hints_includes_only_phantom_route() {
1605                 let mut chanmon_cfgs = create_chanmon_cfgs(4);
1606                 let seed_1 = [42u8; 32];
1607                 let seed_2 = [43u8; 32];
1608                 let cross_node_seed = [44u8; 32];
1609                 chanmon_cfgs[1].keys_manager.backing = PhantomKeysManager::new(&seed_1, 43, 44, &cross_node_seed);
1610                 chanmon_cfgs[2].keys_manager.backing = PhantomKeysManager::new(&seed_2, 43, 44, &cross_node_seed);
1611                 let node_cfgs = create_node_cfgs(4, &chanmon_cfgs);
1612                 let node_chanmgrs = create_node_chanmgrs(4, &node_cfgs, &[None, None, None, None]);
1613                 let nodes = create_network(4, &node_cfgs, &node_chanmgrs);
1614
1615                 let chan_0_2 = create_announced_chan_between_nodes_with_value(&nodes, 0, 2, 100000, 10001);
1616                 nodes[0].node.handle_channel_update(&nodes[2].node.get_our_node_id(), &chan_0_2.1);
1617                 nodes[2].node.handle_channel_update(&nodes[0].node.get_our_node_id(), &chan_0_2.0);
1618                 let _chan_1_2 = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 2, 100000, 10001);
1619
1620                 let chan_0_3 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 3, 100000, 10001);
1621
1622                 // Hints should include `chan_0_3` from as `nodes[3]` only have private channels, and no
1623                 // channels for `nodes[2]` as it contains a mix of public and private channels.
1624                 let mut scid_aliases = HashSet::new();
1625                 scid_aliases.insert(chan_0_3.0.short_channel_id_alias.unwrap());
1626
1627                 match_multi_node_invoice_routes(
1628                         Some(10_000),
1629                         &nodes[2],
1630                         vec![&nodes[2], &nodes[3],],
1631                         scid_aliases,
1632                         true
1633                 );
1634         }
1635
1636         #[test]
1637         #[cfg(feature = "std")]
1638         fn test_multi_node_hints_has_only_lowest_inbound_channel_above_minimum() {
1639                 let mut chanmon_cfgs = create_chanmon_cfgs(3);
1640                 let seed_1 = [42u8; 32];
1641                 let seed_2 = [43u8; 32];
1642                 let cross_node_seed = [44u8; 32];
1643                 chanmon_cfgs[1].keys_manager.backing = PhantomKeysManager::new(&seed_1, 43, 44, &cross_node_seed);
1644                 chanmon_cfgs[2].keys_manager.backing = PhantomKeysManager::new(&seed_2, 43, 44, &cross_node_seed);
1645                 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
1646                 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
1647                 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
1648
1649                 let _chan_0_1_below_amt = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 1, 100_000, 0);
1650                 let _chan_0_1_above_amt_high_inbound = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 1, 500_000, 0);
1651                 let chan_0_1_above_amt_low_inbound = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 1, 180_000, 0);
1652                 let chan_0_2 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 2, 100000, 10001);
1653
1654                 let mut scid_aliases = HashSet::new();
1655                 scid_aliases.insert(chan_0_1_above_amt_low_inbound.0.short_channel_id_alias.unwrap());
1656                 scid_aliases.insert(chan_0_2.0.short_channel_id_alias.unwrap());
1657
1658                 match_multi_node_invoice_routes(
1659                         Some(100_000_000),
1660                         &nodes[1],
1661                         vec![&nodes[1], &nodes[2],],
1662                         scid_aliases,
1663                         false
1664                 );
1665         }
1666
1667         #[test]
1668         #[cfg(feature = "std")]
1669         fn test_multi_node_channels_inbound_capacity_lower_than_invoice_amt_filtering() {
1670                 let mut chanmon_cfgs = create_chanmon_cfgs(4);
1671                 let seed_1 = [42u8; 32];
1672                 let seed_2 = [43u8; 32];
1673                 let cross_node_seed = [44u8; 32];
1674                 chanmon_cfgs[1].keys_manager.backing = PhantomKeysManager::new(&seed_1, 43, 44, &cross_node_seed);
1675                 chanmon_cfgs[2].keys_manager.backing = PhantomKeysManager::new(&seed_2, 43, 44, &cross_node_seed);
1676                 let node_cfgs = create_node_cfgs(4, &chanmon_cfgs);
1677                 let node_chanmgrs = create_node_chanmgrs(4, &node_cfgs, &[None, None, None, None]);
1678                 let nodes = create_network(4, &node_cfgs, &node_chanmgrs);
1679
1680                 let chan_0_2 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 2, 1_000_000, 0);
1681                 let chan_0_3 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 3, 100_000, 0);
1682                 let chan_1_3 = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 3, 200_000, 0);
1683
1684                 // Since the invoice 1 msat above chan_0_3's inbound capacity, it should be filtered out.
1685                 let mut scid_aliases_99_000_001_msat = HashSet::new();
1686                 scid_aliases_99_000_001_msat.insert(chan_0_2.0.short_channel_id_alias.unwrap());
1687                 scid_aliases_99_000_001_msat.insert(chan_1_3.0.short_channel_id_alias.unwrap());
1688
1689                 match_multi_node_invoice_routes(
1690                         Some(99_000_001),
1691                         &nodes[2],
1692                         vec![&nodes[2], &nodes[3],],
1693                         scid_aliases_99_000_001_msat,
1694                         false
1695                 );
1696
1697                 // Since the invoice is exactly at chan_0_3's inbound capacity, it should be included.
1698                 let mut scid_aliases_99_000_000_msat = HashSet::new();
1699                 scid_aliases_99_000_000_msat.insert(chan_0_2.0.short_channel_id_alias.unwrap());
1700                 scid_aliases_99_000_000_msat.insert(chan_0_3.0.short_channel_id_alias.unwrap());
1701                 scid_aliases_99_000_000_msat.insert(chan_1_3.0.short_channel_id_alias.unwrap());
1702
1703                 match_multi_node_invoice_routes(
1704                         Some(99_000_000),
1705                         &nodes[2],
1706                         vec![&nodes[2], &nodes[3],],
1707                         scid_aliases_99_000_000_msat,
1708                         false
1709                 );
1710
1711                 // Since the invoice is above all of `nodes[2]` channels' inbound capacity, all of
1712                 // `nodes[2]` them should be included.
1713                 let mut scid_aliases_300_000_000_msat = HashSet::new();
1714                 scid_aliases_300_000_000_msat.insert(chan_0_2.0.short_channel_id_alias.unwrap());
1715                 scid_aliases_300_000_000_msat.insert(chan_0_3.0.short_channel_id_alias.unwrap());
1716                 scid_aliases_300_000_000_msat.insert(chan_1_3.0.short_channel_id_alias.unwrap());
1717
1718                 match_multi_node_invoice_routes(
1719                         Some(300_000_000),
1720                         &nodes[2],
1721                         vec![&nodes[2], &nodes[3],],
1722                         scid_aliases_300_000_000_msat,
1723                         false
1724                 );
1725
1726                 // Since the no specified amount, all channels should included.
1727                 let mut scid_aliases_no_specified_amount = HashSet::new();
1728                 scid_aliases_no_specified_amount.insert(chan_0_2.0.short_channel_id_alias.unwrap());
1729                 scid_aliases_no_specified_amount.insert(chan_0_3.0.short_channel_id_alias.unwrap());
1730                 scid_aliases_no_specified_amount.insert(chan_1_3.0.short_channel_id_alias.unwrap());
1731
1732                 match_multi_node_invoice_routes(
1733                         None,
1734                         &nodes[2],
1735                         vec![&nodes[2], &nodes[3],],
1736                         scid_aliases_no_specified_amount,
1737                         false
1738                 );
1739         }
1740
1741         #[test]
1742         fn test_multi_node_hints_limited_to_3() {
1743                 let mut chanmon_cfgs = create_chanmon_cfgs(6);
1744                 let seed_1 = [42 as u8; 32];
1745                 let seed_2 = [43 as u8; 32];
1746                 let seed_3 = [44 as u8; 32];
1747                 let seed_4 = [45 as u8; 32];
1748                 let cross_node_seed = [44 as u8; 32];
1749                 chanmon_cfgs[2].keys_manager.backing = PhantomKeysManager::new(&seed_1, 43, 44, &cross_node_seed);
1750                 chanmon_cfgs[3].keys_manager.backing = PhantomKeysManager::new(&seed_2, 43, 44, &cross_node_seed);
1751                 chanmon_cfgs[4].keys_manager.backing = PhantomKeysManager::new(&seed_3, 43, 44, &cross_node_seed);
1752                 chanmon_cfgs[5].keys_manager.backing = PhantomKeysManager::new(&seed_4, 43, 44, &cross_node_seed);
1753                 let node_cfgs = create_node_cfgs(6, &chanmon_cfgs);
1754                 let node_chanmgrs = create_node_chanmgrs(6, &node_cfgs, &[None, None, None, None, None, None]);
1755                 let nodes = create_network(6, &node_cfgs, &node_chanmgrs);
1756
1757                 // Setup each phantom node with two channels from distinct peers.
1758                 let chan_0_2 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 2, 10_000, 0);
1759                 let chan_1_2 = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 2, 20_000, 0);
1760                 let chan_0_3 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 3, 20_000, 0);
1761                 let _chan_1_3 = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 3, 10_000, 0);
1762                 let chan_0_4 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 4, 20_000, 0);
1763                 let _chan_1_4 = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 4, 10_000, 0);
1764                 let _chan_0_5 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 5, 20_000, 0);
1765                 let _chan_1_5 = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 5, 10_000, 0);
1766
1767                 // Set invoice amount > all channels inbound so that every one is eligible for inclusion
1768                 // and hints will be sorted by largest inbound capacity.
1769                 let invoice_amt = Some(100_000_000);
1770
1771                 // With 4 phantom nodes, assert that we include 1 hint per node, up to 3 nodes.
1772                 let mut scid_aliases = HashSet::new();
1773                 scid_aliases.insert(chan_1_2.0.short_channel_id_alias.unwrap());
1774                 scid_aliases.insert(chan_0_3.0.short_channel_id_alias.unwrap());
1775                 scid_aliases.insert(chan_0_4.0.short_channel_id_alias.unwrap());
1776
1777                 match_multi_node_invoice_routes(
1778                         invoice_amt,
1779                         &nodes[3],
1780                         vec![&nodes[2], &nodes[3], &nodes[4], &nodes[5]],
1781                         scid_aliases,
1782                         false,
1783                 );
1784
1785                 // With 2 phantom nodes, assert that we include no more than 3 hints.
1786                 let mut scid_aliases = HashSet::new();
1787                 scid_aliases.insert(chan_1_2.0.short_channel_id_alias.unwrap());
1788                 scid_aliases.insert(chan_0_3.0.short_channel_id_alias.unwrap());
1789                 scid_aliases.insert(chan_0_2.0.short_channel_id_alias.unwrap());
1790
1791                 match_multi_node_invoice_routes(
1792                         invoice_amt,
1793                         &nodes[3],
1794                         vec![&nodes[2], &nodes[3]],
1795                         scid_aliases,
1796                         false,
1797                 );
1798         }
1799
1800         #[test]
1801         fn test_multi_node_hints_at_least_3() {
1802                 let mut chanmon_cfgs = create_chanmon_cfgs(5);
1803                 let seed_1 = [42 as u8; 32];
1804                 let seed_2 = [43 as u8; 32];
1805                 let cross_node_seed = [44 as u8; 32];
1806                 chanmon_cfgs[1].keys_manager.backing = PhantomKeysManager::new(&seed_1, 43, 44, &cross_node_seed);
1807                 chanmon_cfgs[2].keys_manager.backing = PhantomKeysManager::new(&seed_2, 43, 44, &cross_node_seed);
1808                 let node_cfgs = create_node_cfgs(5, &chanmon_cfgs);
1809                 let node_chanmgrs = create_node_chanmgrs(5, &node_cfgs, &[None, None, None, None, None]);
1810                 let nodes = create_network(5, &node_cfgs, &node_chanmgrs);
1811
1812                 let _chan_0_3 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 3, 10_000, 0);
1813                 let chan_1_3 = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 3, 20_000, 0);
1814                 let chan_2_3 = create_unannounced_chan_between_nodes_with_value(&nodes, 2, 3, 30_000, 0);
1815                 let chan_0_4 = create_unannounced_chan_between_nodes_with_value(&nodes, 0, 4, 10_000, 0);
1816
1817                 // Since the invoice amount is above all channels inbound, all four are eligible. Test that
1818                 // we still include 3 hints from 2 distinct nodes sorted by inbound.
1819                 let mut scid_aliases = HashSet::new();
1820                 scid_aliases.insert(chan_1_3.0.short_channel_id_alias.unwrap());
1821                 scid_aliases.insert(chan_2_3.0.short_channel_id_alias.unwrap());
1822                 scid_aliases.insert(chan_0_4.0.short_channel_id_alias.unwrap());
1823
1824                 match_multi_node_invoice_routes(
1825                         Some(100_000_000),
1826                         &nodes[3],
1827                         vec![&nodes[3], &nodes[4],],
1828                         scid_aliases,
1829                         false,
1830                 );
1831         }
1832
1833         fn match_multi_node_invoice_routes<'a, 'b: 'a, 'c: 'b>(
1834                 invoice_amt: Option<u64>,
1835                 invoice_node: &Node<'a, 'b, 'c>,
1836                 network_multi_nodes: Vec<&Node<'a, 'b, 'c>>,
1837                 mut chan_ids_to_match: HashSet<u64>,
1838                 nodes_contains_public_channels: bool
1839         ){
1840                 let phantom_route_hints = network_multi_nodes.iter()
1841                         .map(|node| node.node.get_phantom_route_hints())
1842                         .collect::<Vec<PhantomRouteHints>>();
1843                 let phantom_scids = phantom_route_hints.iter()
1844                         .map(|route_hint| route_hint.phantom_scid)
1845                         .collect::<HashSet<u64>>();
1846
1847                 let invoice = crate::utils::create_phantom_invoice::<&test_utils::TestKeysInterface,
1848                         &test_utils::TestKeysInterface, &test_utils::TestLogger>(invoice_amt, None, "test".to_string(),
1849                                 3600, phantom_route_hints, invoice_node.keys_manager, invoice_node.keys_manager,
1850                                 invoice_node.logger, Currency::BitcoinTestnet, None, Duration::from_secs(1234567)).unwrap();
1851
1852                 let invoice_hints = invoice.private_routes();
1853
1854                 for hint in invoice_hints {
1855                         let hints = &(hint.0).0;
1856                         match hints.len() {
1857                                 1 => {
1858                                         assert!(nodes_contains_public_channels);
1859                                         let phantom_scid = hints[0].short_channel_id;
1860                                         assert!(phantom_scids.contains(&phantom_scid));
1861                                 },
1862                                 2 => {
1863                                         let hint_short_chan_id = hints[0].short_channel_id;
1864                                         assert!(chan_ids_to_match.remove(&hint_short_chan_id));
1865                                         let phantom_scid = hints[1].short_channel_id;
1866                                         assert!(phantom_scids.contains(&phantom_scid));
1867                                 },
1868                                 _ => panic!("Incorrect hint length generated")
1869                         }
1870                 }
1871                 assert!(chan_ids_to_match.is_empty(), "Unmatched short channel ids: {:?}", chan_ids_to_match);
1872         }
1873
1874         #[test]
1875         fn test_create_invoice_fails_with_invalid_custom_min_final_cltv_expiry_delta() {
1876                 let chanmon_cfgs = create_chanmon_cfgs(2);
1877                 let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
1878                 let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
1879                 let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
1880                 let result = crate::utils::create_invoice_from_channelmanager_and_duration_since_epoch(
1881                         nodes[1].node, nodes[1].keys_manager, nodes[1].logger, Currency::BitcoinTestnet,
1882                         Some(10_000), "Some description".into(), Duration::from_secs(1234567), 3600, Some(MIN_FINAL_CLTV_EXPIRY_DELTA - 4),
1883                 );
1884                 match result {
1885                         Err(SignOrCreationError::CreationError(CreationError::MinFinalCltvExpiryDeltaTooShort)) => {},
1886                         _ => panic!(),
1887                 }
1888         }
1889 }