_ Git - rust-lightning/blob - src/ln/router.rs

   1 //! The top-level routing/network map tracking logic lives here.
   2 //!
   3 //! You probably want to create a Router and use that as your RoutingMessageHandler and then
   4 //! interrogate it to get routes for your own payments.
   5
   6 use secp256k1::key::PublicKey;
   7 use secp256k1::{Secp256k1,Message};
   8 use secp256k1;
   9
  10 use bitcoin::util::hash::Sha256dHash;
  11 use bitcoin::blockdata::script::Builder;
  12 use bitcoin::blockdata::opcodes;
  13
  14 use chain::chaininterface::{ChainError, ChainWatchInterface};
  15 use ln::channelmanager;
  16 use ln::msgs::{DecodeError,ErrorAction,HandleError,RoutingMessageHandler,NetAddress,GlobalFeatures};
  17 use ln::msgs;
  18 use util::ser::{Writeable, Readable, Writer, ReadableArgs};
  19 use util::logger::Logger;
  20
  21 use std::cmp;
  22 use std::sync::{RwLock,Arc};
  23 use std::collections::{HashMap,BinaryHeap,BTreeMap};
  24 use std::collections::btree_map::Entry as BtreeEntry;
  25 use std;
  26
  27 /// A hop in a route
  28 #[derive(Clone, PartialEq)]
  29 pub struct RouteHop {
  30         /// The node_id of the node at this hop.
  31         pub pubkey: PublicKey,
  32         /// The channel that should be used from the previous hop to reach this node.
  33         pub short_channel_id: u64,
  34         /// The fee taken on this hop. For the last hop, this should be the full value of the payment.
  35         pub fee_msat: u64,
  36         /// The CLTV delta added for this hop. For the last hop, this should be the full CLTV value
  37         /// expected at the destination, in excess of the current block height.
  38         pub cltv_expiry_delta: u32,
  39 }
  40
  41 /// A route from us through the network to a destination
  42 #[derive(Clone, PartialEq)]
  43 pub struct Route {
  44         /// The list of hops, NOT INCLUDING our own, where the last hop is the destination. Thus, this
  45         /// must always be at least length one. By protocol rules, this may not currently exceed 20 in
  46         /// length.
  47         pub hops: Vec<RouteHop>,
  48 }
  49
  50 impl Writeable for Route {
  51         fn write<W: ::util::ser::Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
  52                 (self.hops.len() as u8).write(writer)?;
  53                 for hop in self.hops.iter() {
  54                         hop.pubkey.write(writer)?;
  55                         hop.short_channel_id.write(writer)?;
  56                         hop.fee_msat.write(writer)?;
  57                         hop.cltv_expiry_delta.write(writer)?;
  58                 }
  59                 Ok(())
  60         }
  61 }
  62
  63 impl<R: ::std::io::Read> Readable<R> for Route {
  64         fn read(reader: &mut R) -> Result<Route, DecodeError> {
  65                 let hops_count: u8 = Readable::read(reader)?;
  66                 let mut hops = Vec::with_capacity(hops_count as usize);
  67                 for _ in 0..hops_count {
  68                         hops.push(RouteHop {
  69                                 pubkey: Readable::read(reader)?,
  70                                 short_channel_id: Readable::read(reader)?,
  71                                 fee_msat: Readable::read(reader)?,
  72                                 cltv_expiry_delta: Readable::read(reader)?,
  73                         });
  74                 }
  75                 Ok(Route {
  76                         hops
  77                 })
  78         }
  79 }
  80
  81 #[derive(PartialEq)]
  82 struct DirectionalChannelInfo {
  83         src_node_id: PublicKey,
  84         last_update: u32,
  85         enabled: bool,
  86         cltv_expiry_delta: u16,
  87         htlc_minimum_msat: u64,
  88         fee_base_msat: u32,
  89         fee_proportional_millionths: u32,
  90         last_update_message: Option<msgs::ChannelUpdate>,
  91 }
  92
  93 impl std::fmt::Display for DirectionalChannelInfo {
  94         fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
  95                 write!(f, "src_node_id {}, last_update {}, enabled {}, cltv_expiry_delta {}, htlc_minimum_msat {}, fee_base_msat {}, fee_proportional_millionths {}", log_pubkey!(self.src_node_id), self.last_update, self.enabled, self.cltv_expiry_delta, self.htlc_minimum_msat, self.fee_base_msat, self.fee_proportional_millionths)?;
  96                 Ok(())
  97         }
  98 }
  99
 100 impl_writeable!(DirectionalChannelInfo, 0, {
 101         src_node_id,
 102         last_update,
 103         enabled,
 104         cltv_expiry_delta,
 105         htlc_minimum_msat,
 106         fee_base_msat,
 107         fee_proportional_millionths,
 108         last_update_message
 109 });
 110
 111 #[derive(PartialEq)]
 112 struct ChannelInfo {
 113         features: GlobalFeatures,
 114         one_to_two: DirectionalChannelInfo,
 115         two_to_one: DirectionalChannelInfo,
 116         //this is cached here so we can send out it later if required by route_init_sync
 117         //keep an eye on this to see if the extra memory is a problem
 118         announcement_message: Option<msgs::ChannelAnnouncement>,
 119 }
 120
 121 impl std::fmt::Display for ChannelInfo {
 122         fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
 123                 write!(f, "features: {}, one_to_two: {}, two_to_one: {}", log_bytes!(self.features.encode()), self.one_to_two, self.two_to_one)?;
 124                 Ok(())
 125         }
 126 }
 127
 128 impl_writeable!(ChannelInfo, 0, {
 129         features,
 130         one_to_two,
 131         two_to_one,
 132         announcement_message
 133 });
 134
 135 #[derive(PartialEq)]
 136 struct NodeInfo {
 137         #[cfg(feature = "non_bitcoin_chain_hash_routing")]
 138         channels: Vec<(u64, Sha256dHash)>,
 139         #[cfg(not(feature = "non_bitcoin_chain_hash_routing"))]
 140         channels: Vec<u64>,
 141
 142         lowest_inbound_channel_fee_base_msat: u32,
 143         lowest_inbound_channel_fee_proportional_millionths: u32,
 144
 145         features: GlobalFeatures,
 146         last_update: u32,
 147         rgb: [u8; 3],
 148         alias: [u8; 32],
 149         addresses: Vec<NetAddress>,
 150         //this is cached here so we can send out it later if required by route_init_sync
 151         //keep an eye on this to see if the extra memory is a problem
 152         announcement_message: Option<msgs::NodeAnnouncement>,
 153 }
 154
 155 impl std::fmt::Display for NodeInfo {
 156         fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
 157                 write!(f, "features: {}, last_update: {}, lowest_inbound_channel_fee_base_msat: {}, lowest_inbound_channel_fee_proportional_millionths: {}, channels: {:?}", log_bytes!(self.features.encode()), self.last_update, self.lowest_inbound_channel_fee_base_msat, self.lowest_inbound_channel_fee_proportional_millionths, &self.channels[..])?;
 158                 Ok(())
 159         }
 160 }
 161
 162 impl Writeable for NodeInfo {
 163         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 164                 (self.channels.len() as u64).write(writer)?;
 165                 for ref chan in self.channels.iter() {
 166                         chan.write(writer)?;
 167                 }
 168                 self.lowest_inbound_channel_fee_base_msat.write(writer)?;
 169                 self.lowest_inbound_channel_fee_proportional_millionths.write(writer)?;
 170                 self.features.write(writer)?;
 171                 self.last_update.write(writer)?;
 172                 self.rgb.write(writer)?;
 173                 self.alias.write(writer)?;
 174                 (self.addresses.len() as u64).write(writer)?;
 175                 for ref addr in &self.addresses {
 176                         addr.write(writer)?;
 177                 }
 178                 self.announcement_message.write(writer)?;
 179                 Ok(())
 180         }
 181 }
 182
 183 const MAX_ALLOC_SIZE: u64 = 64*1024;
 184
 185 impl<R: ::std::io::Read> Readable<R> for NodeInfo {
 186         fn read(reader: &mut R) -> Result<NodeInfo, DecodeError> {
 187                 let channels_count: u64 = Readable::read(reader)?;
 188                 let mut channels = Vec::with_capacity(cmp::min(channels_count, MAX_ALLOC_SIZE / 8) as usize);
 189                 for _ in 0..channels_count {
 190                         channels.push(Readable::read(reader)?);
 191                 }
 192                 let lowest_inbound_channel_fee_base_msat = Readable::read(reader)?;
 193                 let lowest_inbound_channel_fee_proportional_millionths = Readable::read(reader)?;
 194                 let features = Readable::read(reader)?;
 195                 let last_update = Readable::read(reader)?;
 196                 let rgb = Readable::read(reader)?;
 197                 let alias = Readable::read(reader)?;
 198                 let addresses_count: u64 = Readable::read(reader)?;
 199                 let mut addresses = Vec::with_capacity(cmp::min(addresses_count, MAX_ALLOC_SIZE / 40) as usize);
 200                 for _ in 0..addresses_count {
 201                         match Readable::read(reader) {
 202                                 Ok(Ok(addr)) => { addresses.push(addr); },
 203                                 Ok(Err(_)) => return Err(DecodeError::InvalidValue),
 204                                 Err(DecodeError::ShortRead) => return Err(DecodeError::BadLengthDescriptor),
 205                                 _ => unreachable!(),
 206                         }
 207                 }
 208                 let announcement_message = Readable::read(reader)?;
 209                 Ok(NodeInfo {
 210                         channels,
 211                         lowest_inbound_channel_fee_base_msat,
 212                         lowest_inbound_channel_fee_proportional_millionths,
 213                         features,
 214                         last_update,
 215                         rgb,
 216                         alias,
 217                         addresses,
 218                         announcement_message
 219                 })
 220         }
 221 }
 222
 223 #[derive(PartialEq)]
 224 struct NetworkMap {
 225         #[cfg(feature = "non_bitcoin_chain_hash_routing")]
 226         channels: BTreeMap<(u64, Sha256dHash), ChannelInfo>,
 227         #[cfg(not(feature = "non_bitcoin_chain_hash_routing"))]
 228         channels: BTreeMap<u64, ChannelInfo>,
 229
 230         our_node_id: PublicKey,
 231         nodes: BTreeMap<PublicKey, NodeInfo>,
 232 }
 233
 234 impl Writeable for NetworkMap {
 235         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 236                 (self.channels.len() as u64).write(writer)?;
 237                 for (ref chan_id, ref chan_info) in self.channels.iter() {
 238                         (*chan_id).write(writer)?;
 239                         chan_info.write(writer)?;
 240                 }
 241                 self.our_node_id.write(writer)?;
 242                 (self.nodes.len() as u64).write(writer)?;
 243                 for (ref node_id, ref node_info) in self.nodes.iter() {
 244                         node_id.write(writer)?;
 245                         node_info.write(writer)?;
 246                 }
 247                 Ok(())
 248         }
 249 }
 250
 251 impl<R: ::std::io::Read> Readable<R> for NetworkMap {
 252         fn read(reader: &mut R) -> Result<NetworkMap, DecodeError> {
 253                 let channels_count: u64 = Readable::read(reader)?;
 254                 let mut channels = BTreeMap::new();
 255                 for _ in 0..channels_count {
 256                         let chan_id: u64 = Readable::read(reader)?;
 257                         let chan_info = Readable::read(reader)?;
 258                         channels.insert(chan_id, chan_info);
 259                 }
 260                 let our_node_id = Readable::read(reader)?;
 261                 let nodes_count: u64 = Readable::read(reader)?;
 262                 let mut nodes = BTreeMap::new();
 263                 for _ in 0..nodes_count {
 264                         let node_id = Readable::read(reader)?;
 265                         let node_info = Readable::read(reader)?;
 266                         nodes.insert(node_id, node_info);
 267                 }
 268                 Ok(NetworkMap {
 269                         channels,
 270                         our_node_id,
 271                         nodes,
 272                 })
 273         }
 274 }
 275
 276 struct MutNetworkMap<'a> {
 277         #[cfg(feature = "non_bitcoin_chain_hash_routing")]
 278         channels: &'a mut BTreeMap<(u64, Sha256dHash), ChannelInfo>,
 279         #[cfg(not(feature = "non_bitcoin_chain_hash_routing"))]
 280         channels: &'a mut BTreeMap<u64, ChannelInfo>,
 281         nodes: &'a mut BTreeMap<PublicKey, NodeInfo>,
 282 }
 283 impl NetworkMap {
 284         fn borrow_parts(&mut self) -> MutNetworkMap {
 285                 MutNetworkMap {
 286                         channels: &mut self.channels,
 287                         nodes: &mut self.nodes,
 288                 }
 289         }
 290 }
 291 impl std::fmt::Display for NetworkMap {
 292         fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
 293                 write!(f, "Node id {} network map\n[Channels]\n", log_pubkey!(self.our_node_id))?;
 294                 for (key, val) in self.channels.iter() {
 295                         write!(f, " {}: {}\n", key, val)?;
 296                 }
 297                 write!(f, "[Nodes]\n")?;
 298                 for (key, val) in self.nodes.iter() {
 299                         write!(f, " {}: {}\n", log_pubkey!(key), val)?;
 300                 }
 301                 Ok(())
 302         }
 303 }
 304
 305 impl NetworkMap {
 306         #[cfg(feature = "non_bitcoin_chain_hash_routing")]
 307         #[inline]
 308         fn get_key(short_channel_id: u64, chain_hash: Sha256dHash) -> (u64, Sha256dHash) {
 309                 (short_channel_id, chain_hash)
 310         }
 311
 312         #[cfg(not(feature = "non_bitcoin_chain_hash_routing"))]
 313         #[inline]
 314         fn get_key(short_channel_id: u64, _: Sha256dHash) -> u64 {
 315                 short_channel_id
 316         }
 317
 318         #[cfg(feature = "non_bitcoin_chain_hash_routing")]
 319         #[inline]
 320         fn get_short_id(id: &(u64, Sha256dHash)) -> &u64 {
 321                 &id.0
 322         }
 323
 324         #[cfg(not(feature = "non_bitcoin_chain_hash_routing"))]
 325         #[inline]
 326         fn get_short_id(id: &u64) -> &u64 {
 327                 id
 328         }
 329 }
 330
 331 /// A channel descriptor which provides a last-hop route to get_route
 332 pub struct RouteHint {
 333         /// The node_id of the non-target end of the route
 334         pub src_node_id: PublicKey,
 335         /// The short_channel_id of this channel
 336         pub short_channel_id: u64,
 337         /// The static msat-denominated fee which must be paid to use this channel
 338         pub fee_base_msat: u32,
 339         /// The dynamic proportional fee which must be paid to use this channel, denominated in
 340         /// millionths of the value being forwarded to the next hop.
 341         pub fee_proportional_millionths: u32,
 342         /// The difference in CLTV values between this node and the next node.
 343         pub cltv_expiry_delta: u16,
 344         /// The minimum value, in msat, which must be relayed to the next hop.
 345         pub htlc_minimum_msat: u64,
 346 }
 347
 348 /// Tracks a view of the network, receiving updates from peers and generating Routes to
 349 /// payment destinations.
 350 pub struct Router {
 351         secp_ctx: Secp256k1<secp256k1::VerifyOnly>,
 352         network_map: RwLock<NetworkMap>,
 353         chain_monitor: Arc<ChainWatchInterface>,
 354         logger: Arc<Logger>,
 355 }
 356
 357 const SERIALIZATION_VERSION: u8 = 1;
 358 const MIN_SERIALIZATION_VERSION: u8 = 1;
 359
 360 impl Writeable for Router {
 361         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 362                 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
 363                 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
 364
 365                 let network = self.network_map.read().unwrap();
 366                 network.write(writer)?;
 367                 Ok(())
 368         }
 369 }
 370
 371 /// Arguments for the creation of a Router that are not deserialized.
 372 /// At a high-level, the process for deserializing a Router and resuming normal operation is:
 373 /// 1) Deserialize the Router by filling in this struct and calling <Router>::read(reaser, args).
 374 /// 2) Register the new Router with your ChainWatchInterface
 375 pub struct RouterReadArgs {
 376         /// The ChainWatchInterface for use in the Router in the future.
 377         ///
 378         /// No calls to the ChainWatchInterface will be made during deserialization.
 379         pub chain_monitor: Arc<ChainWatchInterface>,
 380         /// The Logger for use in the ChannelManager and which may be used to log information during
 381         /// deserialization.
 382         pub logger: Arc<Logger>,
 383 }
 384
 385 impl<R: ::std::io::Read> ReadableArgs<R, RouterReadArgs> for Router {
 386         fn read(reader: &mut R, args: RouterReadArgs) -> Result<Router, DecodeError> {
 387                 let _ver: u8 = Readable::read(reader)?;
 388                 let min_ver: u8 = Readable::read(reader)?;
 389                 if min_ver > SERIALIZATION_VERSION {
 390                         return Err(DecodeError::UnknownVersion);
 391                 }
 392                 let network_map = Readable::read(reader)?;
 393                 Ok(Router {
 394                         secp_ctx: Secp256k1::verification_only(),
 395                         network_map: RwLock::new(network_map),
 396                         chain_monitor: args.chain_monitor,
 397                         logger: args.logger,
 398                 })
 399         }
 400 }
 401
 402 macro_rules! secp_verify_sig {
 403         ( $secp_ctx: expr, $msg: expr, $sig: expr, $pubkey: expr ) => {
 404                 match $secp_ctx.verify($msg, $sig, $pubkey) {
 405                         Ok(_) => {},
 406                         Err(_) => return Err(HandleError{err: "Invalid signature from remote node", action: None}),
 407                 }
 408         };
 409 }
 410
 411 impl RoutingMessageHandler for Router {
 412         fn handle_node_announcement(&self, msg: &msgs::NodeAnnouncement) -> Result<bool, HandleError> {
 413                 let msg_hash = Message::from_slice(&Sha256dHash::from_data(&msg.contents.encode()[..])[..]).unwrap();
 414                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.signature, &msg.contents.node_id);
 415
 416                 if msg.contents.features.requires_unknown_bits() {
 417                         panic!("Unknown-required-features NodeAnnouncements should never deserialize!");
 418                 }
 419
 420                 let mut network = self.network_map.write().unwrap();
 421                 match network.nodes.get_mut(&msg.contents.node_id) {
 422                         None => Err(HandleError{err: "No existing channels for node_announcement", action: Some(ErrorAction::IgnoreError)}),
 423                         Some(node) => {
 424                                 if node.last_update >= msg.contents.timestamp {
 425                                         return Err(HandleError{err: "Update older than last processed update", action: Some(ErrorAction::IgnoreError)});
 426                                 }
 427
 428                                 node.features = msg.contents.features.clone();
 429                                 node.last_update = msg.contents.timestamp;
 430                                 node.rgb = msg.contents.rgb;
 431                                 node.alias = msg.contents.alias;
 432                                 node.addresses = msg.contents.addresses.clone();
 433
 434                                 let should_relay = msg.contents.excess_data.is_empty() && msg.contents.excess_address_data.is_empty() && !msg.contents.features.supports_unknown_bits();
 435                                 node.announcement_message = if should_relay { Some(msg.clone()) } else { None };
 436                                 Ok(should_relay)
 437                         }
 438                 }
 439         }
 440
 441         fn handle_channel_announcement(&self, msg: &msgs::ChannelAnnouncement) -> Result<bool, HandleError> {
 442                 if msg.contents.node_id_1 == msg.contents.node_id_2 || msg.contents.bitcoin_key_1 == msg.contents.bitcoin_key_2 {
 443                         return Err(HandleError{err: "Channel announcement node had a channel with itself", action: Some(ErrorAction::IgnoreError)});
 444                 }
 445
 446                 let msg_hash = Message::from_slice(&Sha256dHash::from_data(&msg.contents.encode()[..])[..]).unwrap();
 447                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.node_signature_1, &msg.contents.node_id_1);
 448                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.node_signature_2, &msg.contents.node_id_2);
 449                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.bitcoin_signature_1, &msg.contents.bitcoin_key_1);
 450                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.bitcoin_signature_2, &msg.contents.bitcoin_key_2);
 451
 452                 if msg.contents.features.requires_unknown_bits() {
 453                         panic!("Unknown-required-features ChannelAnnouncements should never deserialize!");
 454                 }
 455
 456                 let checked_utxo = match self.chain_monitor.get_chain_utxo(msg.contents.chain_hash, msg.contents.short_channel_id) {
 457                         Ok((script_pubkey, _value)) => {
 458                                 let expected_script = Builder::new().push_opcode(opcodes::All::OP_PUSHNUM_2)
 459                                                                     .push_slice(&msg.contents.bitcoin_key_1.serialize())
 460                                                                     .push_slice(&msg.contents.bitcoin_key_2.serialize())
 461                                                                     .push_opcode(opcodes::All::OP_PUSHNUM_2).push_opcode(opcodes::All::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
 462                                 if script_pubkey != expected_script {
 463                                         return Err(HandleError{err: "Channel announcement keys didn't match on-chain script", action: Some(ErrorAction::IgnoreError)});
 464                                 }
 465                                 //TODO: Check if value is worth storing, use it to inform routing, and compare it
 466                                 //to the new HTLC max field in channel_update
 467                                 true
 468                         },
 469                         Err(ChainError::NotSupported) => {
 470                                 // Tentatively accept, potentially exposing us to DoS attacks
 471                                 false
 472                         },
 473                         Err(ChainError::NotWatched) => {
 474                                 return Err(HandleError{err: "Channel announced on an unknown chain", action: Some(ErrorAction::IgnoreError)});
 475                         },
 476                         Err(ChainError::UnknownTx) => {
 477                                 return Err(HandleError{err: "Channel announced without corresponding UTXO entry", action: Some(ErrorAction::IgnoreError)});
 478                         },
 479                 };
 480
 481                 let mut network_lock = self.network_map.write().unwrap();
 482                 let network = network_lock.borrow_parts();
 483
 484                 let should_relay = msg.contents.excess_data.is_empty() && !msg.contents.features.supports_unknown_bits();
 485
 486                 let chan_info = ChannelInfo {
 487                                 features: msg.contents.features.clone(),
 488                                 one_to_two: DirectionalChannelInfo {
 489                                         src_node_id: msg.contents.node_id_1.clone(),
 490                                         last_update: 0,
 491                                         enabled: false,
 492                                         cltv_expiry_delta: u16::max_value(),
 493                                         htlc_minimum_msat: u64::max_value(),
 494                                         fee_base_msat: u32::max_value(),
 495                                         fee_proportional_millionths: u32::max_value(),
 496                                         last_update_message: None,
 497                                 },
 498                                 two_to_one: DirectionalChannelInfo {
 499                                         src_node_id: msg.contents.node_id_2.clone(),
 500                                         last_update: 0,
 501                                         enabled: false,
 502                                         cltv_expiry_delta: u16::max_value(),
 503                                         htlc_minimum_msat: u64::max_value(),
 504                                         fee_base_msat: u32::max_value(),
 505                                         fee_proportional_millionths: u32::max_value(),
 506                                         last_update_message: None,
 507                                 },
 508                                 announcement_message: if should_relay { Some(msg.clone()) } else { None },
 509                         };
 510
 511                 match network.channels.entry(NetworkMap::get_key(msg.contents.short_channel_id, msg.contents.chain_hash)) {
 512                         BtreeEntry::Occupied(mut entry) => {
 513                                 //TODO: because asking the blockchain if short_channel_id is valid is only optional
 514                                 //in the blockchain API, we need to handle it smartly here, though its unclear
 515                                 //exactly how...
 516                                 if checked_utxo {
 517                                         // Either our UTXO provider is busted, there was a reorg, or the UTXO provider
 518                                         // only sometimes returns results. In any case remove the previous entry. Note
 519                                         // that the spec expects us to "blacklist" the node_ids involved, but we can't
 520                                         // do that because
 521                                         // a) we don't *require* a UTXO provider that always returns results.
 522                                         // b) we don't track UTXOs of channels we know about and remove them if they
 523                                         //    get reorg'd out.
 524                                         // c) it's unclear how to do so without exposing ourselves to massive DoS risk.
 525                                         Self::remove_channel_in_nodes(network.nodes, &entry.get(), msg.contents.short_channel_id);
 526                                         *entry.get_mut() = chan_info;
 527                                 } else {
 528                                         return Err(HandleError{err: "Already have knowledge of channel", action: Some(ErrorAction::IgnoreError)})
 529                                 }
 530                         },
 531                         BtreeEntry::Vacant(entry) => {
 532                                 entry.insert(chan_info);
 533                         }
 534                 };
 535
 536                 macro_rules! add_channel_to_node {
 537                         ( $node_id: expr ) => {
 538                                 match network.nodes.entry($node_id) {
 539                                         BtreeEntry::Occupied(node_entry) => {
 540                                                 node_entry.into_mut().channels.push(NetworkMap::get_key(msg.contents.short_channel_id, msg.contents.chain_hash));
 541                                         },
 542                                         BtreeEntry::Vacant(node_entry) => {
 543                                                 node_entry.insert(NodeInfo {
 544                                                         channels: vec!(NetworkMap::get_key(msg.contents.short_channel_id, msg.contents.chain_hash)),
 545                                                         lowest_inbound_channel_fee_base_msat: u32::max_value(),
 546                                                         lowest_inbound_channel_fee_proportional_millionths: u32::max_value(),
 547                                                         features: GlobalFeatures::new(),
 548                                                         last_update: 0,
 549                                                         rgb: [0; 3],
 550                                                         alias: [0; 32],
 551                                                         addresses: Vec::new(),
 552                                                         announcement_message: None,
 553                                                 });
 554                                         }
 555                                 }
 556                         };
 557                 }
 558
 559                 add_channel_to_node!(msg.contents.node_id_1);
 560                 add_channel_to_node!(msg.contents.node_id_2);
 561
 562                 Ok(should_relay)
 563         }
 564
 565         fn handle_htlc_fail_channel_update(&self, update: &msgs::HTLCFailChannelUpdate) {
 566                 match update {
 567                         &msgs::HTLCFailChannelUpdate::ChannelUpdateMessage { ref msg } => {
 568                                 let _ = self.handle_channel_update(msg);
 569                         },
 570                         &msgs::HTLCFailChannelUpdate::ChannelClosed { ref short_channel_id, ref is_permanent } => {
 571                                 let mut network = self.network_map.write().unwrap();
 572                                 if *is_permanent {
 573                                         if let Some(chan) = network.channels.remove(short_channel_id) {
 574                                                 Self::remove_channel_in_nodes(&mut network.nodes, &chan, *short_channel_id);
 575                                         }
 576                                 } else {
 577                                         if let Some(chan) = network.channels.get_mut(short_channel_id) {
 578                                                 chan.one_to_two.enabled = false;
 579                                                 chan.two_to_one.enabled = false;
 580                                         }
 581                                 }
 582                         },
 583                         &msgs::HTLCFailChannelUpdate::NodeFailure { ref node_id, ref is_permanent } => {
 584                                 if *is_permanent {
 585                                         //TODO: Wholly remove the node
 586                                 } else {
 587                                         self.mark_node_bad(node_id, false);
 588                                 }
 589                         },
 590                 }
 591         }
 592
 593         fn handle_channel_update(&self, msg: &msgs::ChannelUpdate) -> Result<bool, HandleError> {
 594                 let mut network = self.network_map.write().unwrap();
 595                 let dest_node_id;
 596                 let chan_enabled = msg.contents.flags & (1 << 1) != (1 << 1);
 597                 let chan_was_enabled;
 598
 599                 match network.channels.get_mut(&NetworkMap::get_key(msg.contents.short_channel_id, msg.contents.chain_hash)) {
 600                         None => return Err(HandleError{err: "Couldn't find channel for update", action: Some(ErrorAction::IgnoreError)}),
 601                         Some(channel) => {
 602                                 macro_rules! maybe_update_channel_info {
 603                                         ( $target: expr) => {
 604                                                 if $target.last_update >= msg.contents.timestamp {
 605                                                         return Err(HandleError{err: "Update older than last processed update", action: Some(ErrorAction::IgnoreError)});
 606                                                 }
 607                                                 chan_was_enabled = $target.enabled;
 608                                                 $target.last_update = msg.contents.timestamp;
 609                                                 $target.enabled = chan_enabled;
 610                                                 $target.cltv_expiry_delta = msg.contents.cltv_expiry_delta;
 611                                                 $target.htlc_minimum_msat = msg.contents.htlc_minimum_msat;
 612                                                 $target.fee_base_msat = msg.contents.fee_base_msat;
 613                                                 $target.fee_proportional_millionths = msg.contents.fee_proportional_millionths;
 614                                                 $target.last_update_message = if msg.contents.excess_data.is_empty() {
 615                                                         Some(msg.clone())
 616                                                 } else {
 617                                                         None
 618                                                 };
 619                                         }
 620                                 }
 621                                 let msg_hash = Message::from_slice(&Sha256dHash::from_data(&msg.contents.encode()[..])[..]).unwrap();
 622                                 if msg.contents.flags & 1 == 1 {
 623                                         dest_node_id = channel.one_to_two.src_node_id.clone();
 624                                         secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.signature, &channel.two_to_one.src_node_id);
 625                                         maybe_update_channel_info!(channel.two_to_one);
 626                                 } else {
 627                                         dest_node_id = channel.two_to_one.src_node_id.clone();
 628                                         secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.signature, &channel.one_to_two.src_node_id);
 629                                         maybe_update_channel_info!(channel.one_to_two);
 630                                 }
 631                         }
 632                 }
 633
 634                 if chan_enabled {
 635                         let node = network.nodes.get_mut(&dest_node_id).unwrap();
 636                         node.lowest_inbound_channel_fee_base_msat = cmp::min(node.lowest_inbound_channel_fee_base_msat, msg.contents.fee_base_msat);
 637                         node.lowest_inbound_channel_fee_proportional_millionths = cmp::min(node.lowest_inbound_channel_fee_proportional_millionths, msg.contents.fee_proportional_millionths);
 638                 } else if chan_was_enabled {
 639                         let mut lowest_inbound_channel_fee_base_msat = u32::max_value();
 640                         let mut lowest_inbound_channel_fee_proportional_millionths = u32::max_value();
 641
 642                         {
 643                                 let node = network.nodes.get(&dest_node_id).unwrap();
 644
 645                                 for chan_id in node.channels.iter() {
 646                                         let chan = network.channels.get(chan_id).unwrap();
 647                                         if chan.one_to_two.src_node_id == dest_node_id {
 648                                                 lowest_inbound_channel_fee_base_msat = cmp::min(lowest_inbound_channel_fee_base_msat, chan.two_to_one.fee_base_msat);
 649                                                 lowest_inbound_channel_fee_proportional_millionths = cmp::min(lowest_inbound_channel_fee_proportional_millionths, chan.two_to_one.fee_proportional_millionths);
 650                                         } else {
 651                                                 lowest_inbound_channel_fee_base_msat = cmp::min(lowest_inbound_channel_fee_base_msat, chan.one_to_two.fee_base_msat);
 652                                                 lowest_inbound_channel_fee_proportional_millionths = cmp::min(lowest_inbound_channel_fee_proportional_millionths, chan.one_to_two.fee_proportional_millionths);
 653                                         }
 654                                 }
 655                         }
 656
 657                         //TODO: satisfy the borrow-checker without a double-map-lookup :(
 658                         let mut_node = network.nodes.get_mut(&dest_node_id).unwrap();
 659                         mut_node.lowest_inbound_channel_fee_base_msat = lowest_inbound_channel_fee_base_msat;
 660                         mut_node.lowest_inbound_channel_fee_proportional_millionths = lowest_inbound_channel_fee_proportional_millionths;
 661                 }
 662
 663                 Ok(msg.contents.excess_data.is_empty())
 664         }
 665
 666
 667         fn get_next_channel_announcements(&self, starting_point: u64, batch_amount: u8) -> Vec<(msgs::ChannelAnnouncement, msgs::ChannelUpdate,msgs::ChannelUpdate)> {
 668                 let mut result = Vec::with_capacity(batch_amount as usize);
 669                 let network = self.network_map.read().unwrap();
 670                 let mut iter = network.channels.range(starting_point..);
 671                 while result.len() < batch_amount as usize {
 672                         if let Some((_, ref chan)) = iter.next() {
 673                                 if chan.announcement_message.is_some() &&
 674                                                 chan.one_to_two.last_update_message.is_some() &&
 675                                                 chan.two_to_one.last_update_message.is_some() {
 676                                         result.push((chan.announcement_message.clone().unwrap(),
 677                                                 chan.one_to_two.last_update_message.clone().unwrap(),
 678                                                 chan.two_to_one.last_update_message.clone().unwrap()));
 679                                 } else {
 680                                         // TODO: We may end up sending un-announced channel_updates if we are sending
 681                                         // initial sync data while receiving announce/updates for this channel.
 682                                 }
 683                         } else {
 684                                 return result;
 685                         }
 686                 }
 687                 result
 688         }
 689
 690         fn get_next_node_announcements(&self, starting_point: Option<&PublicKey>, batch_amount: u8) -> Vec<msgs::NodeAnnouncement> {
 691                 let mut result = Vec::with_capacity(batch_amount as usize);
 692                 let network = self.network_map.read().unwrap();
 693                 let mut iter = if let Some(pubkey) = starting_point {
 694                                 let mut iter = network.nodes.range((*pubkey)..);
 695                                 iter.next();
 696                                 iter
 697                         } else {
 698                                 network.nodes.range(..)
 699                         };
 700                 while result.len() < batch_amount as usize {
 701                         if let Some((_, ref node)) = iter.next() {
 702                                 if node.announcement_message.is_some() {
 703                                         result.push(node.announcement_message.clone().unwrap());
 704                                 }
 705                         } else {
 706                                 return result;
 707                         }
 708                 }
 709                 result
 710         }
 711 }
 712
 713 #[derive(Eq, PartialEq)]
 714 struct RouteGraphNode {
 715         pubkey: PublicKey,
 716         lowest_fee_to_peer_through_node: u64,
 717         lowest_fee_to_node: u64,
 718 }
 719
 720 impl cmp::Ord for RouteGraphNode {
 721         fn cmp(&self, other: &RouteGraphNode) -> cmp::Ordering {
 722                 other.lowest_fee_to_peer_through_node.cmp(&self.lowest_fee_to_peer_through_node)
 723                         .then_with(|| other.pubkey.serialize().cmp(&self.pubkey.serialize()))
 724         }
 725 }
 726
 727 impl cmp::PartialOrd for RouteGraphNode {
 728         fn partial_cmp(&self, other: &RouteGraphNode) -> Option<cmp::Ordering> {
 729                 Some(self.cmp(other))
 730         }
 731 }
 732
 733 struct DummyDirectionalChannelInfo {
 734         src_node_id: PublicKey,
 735         cltv_expiry_delta: u32,
 736         htlc_minimum_msat: u64,
 737         fee_base_msat: u32,
 738         fee_proportional_millionths: u32,
 739 }
 740
 741 impl Router {
 742         /// Creates a new router with the given node_id to be used as the source for get_route()
 743         pub fn new(our_pubkey: PublicKey, chain_monitor: Arc<ChainWatchInterface>, logger: Arc<Logger>) -> Router {
 744                 let mut nodes = BTreeMap::new();
 745                 nodes.insert(our_pubkey.clone(), NodeInfo {
 746                         channels: Vec::new(),
 747                         lowest_inbound_channel_fee_base_msat: u32::max_value(),
 748                         lowest_inbound_channel_fee_proportional_millionths: u32::max_value(),
 749                         features: GlobalFeatures::new(),
 750                         last_update: 0,
 751                         rgb: [0; 3],
 752                         alias: [0; 32],
 753                         addresses: Vec::new(),
 754                         announcement_message: None,
 755                 });
 756                 Router {
 757                         secp_ctx: Secp256k1::verification_only(),
 758                         network_map: RwLock::new(NetworkMap {
 759                                 channels: BTreeMap::new(),
 760                                 our_node_id: our_pubkey,
 761                                 nodes: nodes,
 762                         }),
 763                         chain_monitor,
 764                         logger,
 765                 }
 766         }
 767
 768         /// Dumps the entire network view of this Router to the logger provided in the constructor at
 769         /// level Trace
 770         pub fn trace_state(&self) {
 771                 log_trace!(self, "{}", self.network_map.read().unwrap());
 772         }
 773
 774         /// Get network addresses by node id
 775         pub fn get_addresses(&self, pubkey: &PublicKey) -> Option<Vec<NetAddress>> {
 776                 let network = self.network_map.read().unwrap();
 777                 network.nodes.get(pubkey).map(|n| n.addresses.clone())
 778         }
 779
 780         /// Marks a node as having failed a route. This will avoid re-using the node in routes for now,
 781         /// with an expotnential decay in node "badness". Note that there is deliberately no
 782         /// mark_channel_bad as a node may simply lie and suggest that an upstream channel from it is
 783         /// what failed the route and not the node itself. Instead, setting the blamed_upstream_node
 784         /// boolean will reduce the penalty, returning the node to usability faster. If the node is
 785         /// behaving correctly, it will disable the failing channel and we will use it again next time.
 786         pub fn mark_node_bad(&self, _node_id: &PublicKey, _blamed_upstream_node: bool) {
 787                 unimplemented!();
 788         }
 789
 790         fn remove_channel_in_nodes(nodes: &mut BTreeMap<PublicKey, NodeInfo>, chan: &ChannelInfo, short_channel_id: u64) {
 791                 macro_rules! remove_from_node {
 792                         ($node_id: expr) => {
 793                                 if let BtreeEntry::Occupied(mut entry) = nodes.entry($node_id) {
 794                                         entry.get_mut().channels.retain(|chan_id| {
 795                                                 short_channel_id != *NetworkMap::get_short_id(chan_id)
 796                                         });
 797                                         if entry.get().channels.is_empty() {
 798                                                 entry.remove_entry();
 799                                         }
 800                                 } else {
 801                                         panic!("Had channel that pointed to unknown node (ie inconsistent network map)!");
 802                                 }
 803                         }
 804                 }
 805                 remove_from_node!(chan.one_to_two.src_node_id);
 806                 remove_from_node!(chan.two_to_one.src_node_id);
 807         }
 808
 809         /// Gets a route from us to the given target node.
 810         ///
 811         /// Extra routing hops between known nodes and the target will be used if they are included in
 812         /// last_hops.
 813         ///
 814         /// If some channels aren't announced, it may be useful to fill in a first_hops with the
 815         /// results from a local ChannelManager::list_usable_channels() call. If it is filled in, our
 816         /// (this Router's) view of our local channels will be ignored, and only those in first_hops
 817         /// will be used.
 818         ///
 819         /// Panics if first_hops contains channels without short_channel_ids
 820         /// (ChannelManager::list_usable_channels will never include such channels).
 821         ///
 822         /// The fees on channels from us to next-hops are ignored (as they are assumed to all be
 823         /// equal), however the enabled/disabled bit on such channels as well as the htlc_minimum_msat
 824         /// *is* checked as they may change based on the receiving node.
 825         pub fn get_route(&self, target: &PublicKey, first_hops: Option<&[channelmanager::ChannelDetails]>, last_hops: &[RouteHint], final_value_msat: u64, final_cltv: u32) -> Result<Route, HandleError> {
 826                 // TODO: Obviously *only* using total fee cost sucks. We should consider weighting by
 827                 // uptime/success in using a node in the past.
 828                 let network = self.network_map.read().unwrap();
 829
 830                 if *target == network.our_node_id {
 831                         return Err(HandleError{err: "Cannot generate a route to ourselves", action: None});
 832                 }
 833
 834                 if final_value_msat > 21_000_000 * 1_0000_0000 * 1000 {
 835                         return Err(HandleError{err: "Cannot generate a route of more value than all existing satoshis", action: None});
 836                 }
 837
 838                 // We do a dest-to-source Dijkstra's sorting by each node's distance from the destination
 839                 // plus the minimum per-HTLC fee to get from it to another node (aka "shitty A*").
 840                 // TODO: There are a few tweaks we could do, including possibly pre-calculating more stuff
 841                 // to use as the A* heuristic beyond just the cost to get one node further than the current
 842                 // one.
 843
 844                 let dummy_directional_info = DummyDirectionalChannelInfo { // used for first_hops routes
 845                         src_node_id: network.our_node_id.clone(),
 846                         cltv_expiry_delta: 0,
 847                         htlc_minimum_msat: 0,
 848                         fee_base_msat: 0,
 849                         fee_proportional_millionths: 0,
 850                 };
 851
 852                 let mut targets = BinaryHeap::new(); //TODO: Do we care about switching to eg Fibbonaci heap?
 853                 let mut dist = HashMap::with_capacity(network.nodes.len());
 854
 855                 let mut first_hop_targets = HashMap::with_capacity(if first_hops.is_some() { first_hops.as_ref().unwrap().len() } else { 0 });
 856                 if let Some(hops) = first_hops {
 857                         for chan in hops {
 858                                 let short_channel_id = chan.short_channel_id.expect("first_hops should be filled in with usable channels, not pending ones");
 859                                 if chan.remote_network_id == *target {
 860                                         return Ok(Route {
 861                                                 hops: vec![RouteHop {
 862                                                         pubkey: chan.remote_network_id,
 863                                                         short_channel_id,
 864                                                         fee_msat: final_value_msat,
 865                                                         cltv_expiry_delta: final_cltv,
 866                                                 }],
 867                                         });
 868                                 }
 869                                 first_hop_targets.insert(chan.remote_network_id, short_channel_id);
 870                         }
 871                         if first_hop_targets.is_empty() {
 872                                 return Err(HandleError{err: "Cannot route when there are no outbound routes away from us", action: None});
 873                         }
 874                 }
 875
 876                 macro_rules! add_entry {
 877                         // Adds entry which goes from the node pointed to by $directional_info to
 878                         // $dest_node_id over the channel with id $chan_id with fees described in
 879                         // $directional_info.
 880                         ( $chan_id: expr, $dest_node_id: expr, $directional_info: expr, $starting_fee_msat: expr ) => {
 881                                 //TODO: Explore simply adding fee to hit htlc_minimum_msat
 882                                 if $starting_fee_msat as u64 + final_value_msat > $directional_info.htlc_minimum_msat {
 883                                         let proportional_fee_millions = ($starting_fee_msat + final_value_msat).checked_mul($directional_info.fee_proportional_millionths as u64);
 884                                         if let Some(new_fee) = proportional_fee_millions.and_then(|part| {
 885                                                         ($directional_info.fee_base_msat as u64).checked_add(part / 1000000) })
 886                                         {
 887                                                 let mut total_fee = $starting_fee_msat as u64;
 888                                                 let hm_entry = dist.entry(&$directional_info.src_node_id);
 889                                                 let old_entry = hm_entry.or_insert_with(|| {
 890                                                         let node = network.nodes.get(&$directional_info.src_node_id).unwrap();
 891                                                         (u64::max_value(),
 892                                                                 node.lowest_inbound_channel_fee_base_msat,
 893                                                                 node.lowest_inbound_channel_fee_proportional_millionths,
 894                                                                 RouteHop {
 895                                                                         pubkey: $dest_node_id.clone(),
 896                                                                         short_channel_id: 0,
 897                                                                         fee_msat: 0,
 898                                                                         cltv_expiry_delta: 0,
 899                                                         })
 900                                                 });
 901                                                 if $directional_info.src_node_id != network.our_node_id {
 902                                                         // Ignore new_fee for channel-from-us as we assume all channels-from-us
 903                                                         // will have the same effective-fee
 904                                                         total_fee += new_fee;
 905                                                         if let Some(fee_inc) = final_value_msat.checked_add(total_fee).and_then(|inc| { (old_entry.2 as u64).checked_mul(inc) }) {
 906                                                                 total_fee += fee_inc / 1000000 + (old_entry.1 as u64);
 907                                                         } else {
 908                                                                 // max_value means we'll always fail the old_entry.0 > total_fee check
 909                                                                 total_fee = u64::max_value();
 910                                                         }
 911                                                 }
 912                                                 let new_graph_node = RouteGraphNode {
 913                                                         pubkey: $directional_info.src_node_id,
 914                                                         lowest_fee_to_peer_through_node: total_fee,
 915                                                         lowest_fee_to_node: $starting_fee_msat as u64 + new_fee,
 916                                                 };
 917                                                 if old_entry.0 > total_fee {
 918                                                         targets.push(new_graph_node);
 919                                                         old_entry.0 = total_fee;
 920                                                         old_entry.3 = RouteHop {
 921                                                                 pubkey: $dest_node_id.clone(),
 922                                                                 short_channel_id: $chan_id.clone(),
 923                                                                 fee_msat: new_fee, // This field is ignored on the last-hop anyway
 924                                                                 cltv_expiry_delta: $directional_info.cltv_expiry_delta as u32,
 925                                                         }
 926                                                 }
 927                                         }
 928                                 }
 929                         };
 930                 }
 931
 932                 macro_rules! add_entries_to_cheapest_to_target_node {
 933                         ( $node: expr, $node_id: expr, $fee_to_target_msat: expr ) => {
 934                                 if first_hops.is_some() {
 935                                         if let Some(first_hop) = first_hop_targets.get(&$node_id) {
 936                                                 add_entry!(first_hop, $node_id, dummy_directional_info, $fee_to_target_msat);
 937                                         }
 938                                 }
 939
 940                                 for chan_id in $node.channels.iter() {
 941                                         let chan = network.channels.get(chan_id).unwrap();
 942                                         if chan.one_to_two.src_node_id == *$node_id {
 943                                                 // ie $node is one, ie next hop in A* is two, via the two_to_one channel
 944                                                 if first_hops.is_none() || chan.two_to_one.src_node_id != network.our_node_id {
 945                                                         if chan.two_to_one.enabled {
 946                                                                 add_entry!(chan_id, chan.one_to_two.src_node_id, chan.two_to_one, $fee_to_target_msat);
 947                                                         }
 948                                                 }
 949                                         } else {
 950                                                 if first_hops.is_none() || chan.one_to_two.src_node_id != network.our_node_id {
 951                                                         if chan.one_to_two.enabled {
 952                                                                 add_entry!(chan_id, chan.two_to_one.src_node_id, chan.one_to_two, $fee_to_target_msat);
 953                                                         }
 954                                                 }
 955                                         }
 956                                 }
 957                         };
 958                 }
 959
 960                 match network.nodes.get(target) {
 961                         None => {},
 962                         Some(node) => {
 963                                 add_entries_to_cheapest_to_target_node!(node, target, 0);
 964                         },
 965                 }
 966
 967                 for hop in last_hops.iter() {
 968                         if first_hops.is_none() || hop.src_node_id != network.our_node_id { // first_hop overrules last_hops
 969                                 if network.nodes.get(&hop.src_node_id).is_some() {
 970                                         if first_hops.is_some() {
 971                                                 if let Some(first_hop) = first_hop_targets.get(&hop.src_node_id) {
 972                                                         add_entry!(first_hop, hop.src_node_id, dummy_directional_info, 0);
 973                                                 }
 974                                         }
 975                                         add_entry!(hop.short_channel_id, target, hop, 0);
 976                                 }
 977                         }
 978                 }
 979
 980                 while let Some(RouteGraphNode { pubkey, lowest_fee_to_node, .. }) = targets.pop() {
 981                         if pubkey == network.our_node_id {
 982                                 let mut res = vec!(dist.remove(&network.our_node_id).unwrap().3);
 983                                 while res.last().unwrap().pubkey != *target {
 984                                         let new_entry = match dist.remove(&res.last().unwrap().pubkey) {
 985                                                 Some(hop) => hop.3,
 986                                                 None => return Err(HandleError{err: "Failed to find a non-fee-overflowing path to the given destination", action: None}),
 987                                         };
 988                                         res.last_mut().unwrap().fee_msat = new_entry.fee_msat;
 989                                         res.last_mut().unwrap().cltv_expiry_delta = new_entry.cltv_expiry_delta;
 990                                         res.push(new_entry);
 991                                 }
 992                                 res.last_mut().unwrap().fee_msat = final_value_msat;
 993                                 res.last_mut().unwrap().cltv_expiry_delta = final_cltv;
 994                                 let route = Route { hops: res };
 995                                 log_trace!(self, "Got route: {}", log_route!(route));
 996                                 return Ok(route);
 997                         }
 998
 999                         match network.nodes.get(&pubkey) {
1000                                 None => {},
1001                                 Some(node) => {
1002                                         add_entries_to_cheapest_to_target_node!(node, &pubkey, lowest_fee_to_node);
1003                                 },
1004                         }
1005                 }
1006
1007                 Err(HandleError{err: "Failed to find a path to the given destination", action: None})
1008         }
1009 }
1010
1011 #[cfg(test)]
1012 mod tests {
1013         use chain::chaininterface;
1014         use ln::channelmanager;
1015         use ln::router::{Router,NodeInfo,NetworkMap,ChannelInfo,DirectionalChannelInfo,RouteHint};
1016         use ln::msgs::GlobalFeatures;
1017         use util::test_utils;
1018         use util::test_utils::TestVecWriter;
1019         use util::logger::Logger;
1020         use util::ser::{Writeable, Readable};
1021
1022         use bitcoin::util::hash::Sha256dHash;
1023         use bitcoin::network::constants::Network;
1024
1025         use hex;
1026
1027         use secp256k1::key::{PublicKey,SecretKey};
1028         use secp256k1::Secp256k1;
1029
1030         use std::sync::Arc;
1031
1032         #[test]
1033         fn route_test() {
1034                 let secp_ctx = Secp256k1::new();
1035                 let our_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap());
1036                 let logger: Arc<Logger> = Arc::new(test_utils::TestLogger::new());
1037                 let chain_monitor = Arc::new(chaininterface::ChainWatchInterfaceUtil::new(Network::Testnet, Arc::clone(&logger)));
1038                 let router = Router::new(our_id, chain_monitor, Arc::clone(&logger));
1039
1040                 // Build network from our_id to node8:
1041                 //
1042                 //        -1(1)2-  node1  -1(3)2-
1043                 //       /                       \
1044                 // our_id -1(12)2- node8 -1(13)2--- node3
1045                 //       \                       /
1046                 //        -1(2)2-  node2  -1(4)2-
1047                 //
1048                 //
1049                 // chan1  1-to-2: disabled
1050                 // chan1  2-to-1: enabled, 0 fee
1051                 //
1052                 // chan2  1-to-2: enabled, ignored fee
1053                 // chan2  2-to-1: enabled, 0 fee
1054                 //
1055                 // chan3  1-to-2: enabled, 0 fee
1056                 // chan3  2-to-1: enabled, 100 msat fee
1057                 //
1058                 // chan4  1-to-2: enabled, 100% fee
1059                 // chan4  2-to-1: enabled, 0 fee
1060                 //
1061                 // chan12 1-to-2: enabled, ignored fee
1062                 // chan12 2-to-1: enabled, 0 fee
1063                 //
1064                 // chan13 1-to-2: enabled, 200% fee
1065                 // chan13 2-to-1: enabled, 0 fee
1066                 //
1067                 //
1068                 //       -1(5)2- node4 -1(8)2--
1069                 //       |         2          |
1070                 //       |       (11)         |
1071                 //      /          1           \
1072                 // node3--1(6)2- node5 -1(9)2--- node7 (not in global route map)
1073                 //      \                      /
1074                 //       -1(7)2- node6 -1(10)2-
1075                 //
1076                 // chan5  1-to-2: enabled, 100 msat fee
1077                 // chan5  2-to-1: enabled, 0 fee
1078                 //
1079                 // chan6  1-to-2: enabled, 0 fee
1080                 // chan6  2-to-1: enabled, 0 fee
1081                 //
1082                 // chan7  1-to-2: enabled, 100% fee
1083                 // chan7  2-to-1: enabled, 0 fee
1084                 //
1085                 // chan8  1-to-2: enabled, variable fee (0 then 1000 msat)
1086                 // chan8  2-to-1: enabled, 0 fee
1087                 //
1088                 // chan9  1-to-2: enabled, 1001 msat fee
1089                 // chan9  2-to-1: enabled, 0 fee
1090                 //
1091                 // chan10 1-to-2: enabled, 0 fee
1092                 // chan10 2-to-1: enabled, 0 fee
1093                 //
1094                 // chan11 1-to-2: enabled, 0 fee
1095                 // chan11 2-to-1: enabled, 0 fee
1096
1097                 let node1 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &hex::decode("0202020202020202020202020202020202020202020202020202020202020202").unwrap()[..]).unwrap());
1098                 let node2 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &hex::decode("0303030303030303030303030303030303030303030303030303030303030303").unwrap()[..]).unwrap());
1099                 let node3 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &hex::decode("0404040404040404040404040404040404040404040404040404040404040404").unwrap()[..]).unwrap());
1100                 let node4 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &hex::decode("0505050505050505050505050505050505050505050505050505050505050505").unwrap()[..]).unwrap());
1101                 let node5 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &hex::decode("0606060606060606060606060606060606060606060606060606060606060606").unwrap()[..]).unwrap());
1102                 let node6 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &hex::decode("0707070707070707070707070707070707070707070707070707070707070707").unwrap()[..]).unwrap());
1103                 let node7 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &hex::decode("0808080808080808080808080808080808080808080808080808080808080808").unwrap()[..]).unwrap());
1104                 let node8 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &hex::decode("0909090909090909090909090909090909090909090909090909090909090909").unwrap()[..]).unwrap());
1105
1106                 let zero_hash = Sha256dHash::from_data(&[0; 32]);
1107
1108                 {
1109                         let mut network = router.network_map.write().unwrap();
1110
1111                         network.nodes.insert(node1.clone(), NodeInfo {
1112                                 channels: vec!(NetworkMap::get_key(1, zero_hash.clone()), NetworkMap::get_key(3, zero_hash.clone())),
1113                                 lowest_inbound_channel_fee_base_msat: 100,
1114                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1115                                 features: GlobalFeatures::new(),
1116                                 last_update: 1,
1117                                 rgb: [0; 3],
1118                                 alias: [0; 32],
1119                                 addresses: Vec::new(),
1120                                 announcement_message: None,
1121                         });
1122                         network.channels.insert(NetworkMap::get_key(1, zero_hash.clone()), ChannelInfo {
1123                                 features: GlobalFeatures::new(),
1124                                 one_to_two: DirectionalChannelInfo {
1125                                         src_node_id: our_id.clone(),
1126                                         last_update: 0,
1127                                         enabled: false,
1128                                         cltv_expiry_delta: u16::max_value(), // This value should be ignored
1129                                         htlc_minimum_msat: 0,
1130                                         fee_base_msat: u32::max_value(), // This value should be ignored
1131                                         fee_proportional_millionths: u32::max_value(), // This value should be ignored
1132                                         last_update_message: None,
1133                                 }, two_to_one: DirectionalChannelInfo {
1134                                         src_node_id: node1.clone(),
1135                                         last_update: 0,
1136                                         enabled: true,
1137                                         cltv_expiry_delta: 0,
1138                                         htlc_minimum_msat: 0,
1139                                         fee_base_msat: 0,
1140                                         fee_proportional_millionths: 0,
1141                                         last_update_message: None,
1142                                 },
1143                                 announcement_message: None,
1144                         });
1145                         network.nodes.insert(node2.clone(), NodeInfo {
1146                                 channels: vec!(NetworkMap::get_key(2, zero_hash.clone()), NetworkMap::get_key(4, zero_hash.clone())),
1147                                 lowest_inbound_channel_fee_base_msat: 0,
1148                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1149                                 features: GlobalFeatures::new(),
1150                                 last_update: 1,
1151                                 rgb: [0; 3],
1152                                 alias: [0; 32],
1153                                 addresses: Vec::new(),
1154                                 announcement_message: None,
1155                         });
1156                         network.channels.insert(NetworkMap::get_key(2, zero_hash.clone()), ChannelInfo {
1157                                 features: GlobalFeatures::new(),
1158                                 one_to_two: DirectionalChannelInfo {
1159                                         src_node_id: our_id.clone(),
1160                                         last_update: 0,
1161                                         enabled: true,
1162                                         cltv_expiry_delta: u16::max_value(), // This value should be ignored
1163                                         htlc_minimum_msat: 0,
1164                                         fee_base_msat: u32::max_value(), // This value should be ignored
1165                                         fee_proportional_millionths: u32::max_value(), // This value should be ignored
1166                                         last_update_message: None,
1167                                 }, two_to_one: DirectionalChannelInfo {
1168                                         src_node_id: node2.clone(),
1169                                         last_update: 0,
1170                                         enabled: true,
1171                                         cltv_expiry_delta: 0,
1172                                         htlc_minimum_msat: 0,
1173                                         fee_base_msat: 0,
1174                                         fee_proportional_millionths: 0,
1175                                         last_update_message: None,
1176                                 },
1177                                 announcement_message: None,
1178                         });
1179                         network.nodes.insert(node8.clone(), NodeInfo {
1180                                 channels: vec!(NetworkMap::get_key(12, zero_hash.clone()), NetworkMap::get_key(13, zero_hash.clone())),
1181                                 lowest_inbound_channel_fee_base_msat: 0,
1182                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1183                                 features: GlobalFeatures::new(),
1184                                 last_update: 1,
1185                                 rgb: [0; 3],
1186                                 alias: [0; 32],
1187                                 addresses: Vec::new(),
1188                                 announcement_message: None,
1189                         });
1190                         network.channels.insert(NetworkMap::get_key(12, zero_hash.clone()), ChannelInfo {
1191                                 features: GlobalFeatures::new(),
1192                                 one_to_two: DirectionalChannelInfo {
1193                                         src_node_id: our_id.clone(),
1194                                         last_update: 0,
1195                                         enabled: true,
1196                                         cltv_expiry_delta: u16::max_value(), // This value should be ignored
1197                                         htlc_minimum_msat: 0,
1198                                         fee_base_msat: u32::max_value(), // This value should be ignored
1199                                         fee_proportional_millionths: u32::max_value(), // This value should be ignored
1200                                         last_update_message: None,
1201                                 }, two_to_one: DirectionalChannelInfo {
1202                                         src_node_id: node8.clone(),
1203                                         last_update: 0,
1204                                         enabled: true,
1205                                         cltv_expiry_delta: 0,
1206                                         htlc_minimum_msat: 0,
1207                                         fee_base_msat: 0,
1208                                         fee_proportional_millionths: 0,
1209                                         last_update_message: None,
1210                                 },
1211                                 announcement_message: None,
1212                         });
1213                         network.nodes.insert(node3.clone(), NodeInfo {
1214                                 channels: vec!(
1215                                         NetworkMap::get_key(3, zero_hash.clone()),
1216                                         NetworkMap::get_key(4, zero_hash.clone()),
1217                                         NetworkMap::get_key(13, zero_hash.clone()),
1218                                         NetworkMap::get_key(5, zero_hash.clone()),
1219                                         NetworkMap::get_key(6, zero_hash.clone()),
1220                                         NetworkMap::get_key(7, zero_hash.clone())),
1221                                 lowest_inbound_channel_fee_base_msat: 0,
1222                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1223                                 features: GlobalFeatures::new(),
1224                                 last_update: 1,
1225                                 rgb: [0; 3],
1226                                 alias: [0; 32],
1227                                 addresses: Vec::new(),
1228                                 announcement_message: None,
1229                         });
1230                         network.channels.insert(NetworkMap::get_key(3, zero_hash.clone()), ChannelInfo {
1231                                 features: GlobalFeatures::new(),
1232                                 one_to_two: DirectionalChannelInfo {
1233                                         src_node_id: node1.clone(),
1234                                         last_update: 0,
1235                                         enabled: true,
1236                                         cltv_expiry_delta: (3 << 8) | 1,
1237                                         htlc_minimum_msat: 0,
1238                                         fee_base_msat: 0,
1239                                         fee_proportional_millionths: 0,
1240                                         last_update_message: None,
1241                                 }, two_to_one: DirectionalChannelInfo {
1242                                         src_node_id: node3.clone(),
1243                                         last_update: 0,
1244                                         enabled: true,
1245                                         cltv_expiry_delta: (3 << 8) | 2,
1246                                         htlc_minimum_msat: 0,
1247                                         fee_base_msat: 100,
1248                                         fee_proportional_millionths: 0,
1249                                         last_update_message: None,
1250                                 },
1251                                 announcement_message: None,
1252                         });
1253                         network.channels.insert(NetworkMap::get_key(4, zero_hash.clone()), ChannelInfo {
1254                                 features: GlobalFeatures::new(),
1255                                 one_to_two: DirectionalChannelInfo {
1256                                         src_node_id: node2.clone(),
1257                                         last_update: 0,
1258                                         enabled: true,
1259                                         cltv_expiry_delta: (4 << 8) | 1,
1260                                         htlc_minimum_msat: 0,
1261                                         fee_base_msat: 0,
1262                                         fee_proportional_millionths: 1000000,
1263                                         last_update_message: None,
1264                                 }, two_to_one: DirectionalChannelInfo {
1265                                         src_node_id: node3.clone(),
1266                                         last_update: 0,
1267                                         enabled: true,
1268                                         cltv_expiry_delta: (4 << 8) | 2,
1269                                         htlc_minimum_msat: 0,
1270                                         fee_base_msat: 0,
1271                                         fee_proportional_millionths: 0,
1272                                         last_update_message: None,
1273                                 },
1274                                 announcement_message: None,
1275                         });
1276                         network.channels.insert(NetworkMap::get_key(13, zero_hash.clone()), ChannelInfo {
1277                                 features: GlobalFeatures::new(),
1278                                 one_to_two: DirectionalChannelInfo {
1279                                         src_node_id: node8.clone(),
1280                                         last_update: 0,
1281                                         enabled: true,
1282                                         cltv_expiry_delta: (13 << 8) | 1,
1283                                         htlc_minimum_msat: 0,
1284                                         fee_base_msat: 0,
1285                                         fee_proportional_millionths: 2000000,
1286                                         last_update_message: None,
1287                                 }, two_to_one: DirectionalChannelInfo {
1288                                         src_node_id: node3.clone(),
1289                                         last_update: 0,
1290                                         enabled: true,
1291                                         cltv_expiry_delta: (13 << 8) | 2,
1292                                         htlc_minimum_msat: 0,
1293                                         fee_base_msat: 0,
1294                                         fee_proportional_millionths: 0,
1295                                         last_update_message: None,
1296                                 },
1297                                 announcement_message: None,
1298                         });
1299                         network.nodes.insert(node4.clone(), NodeInfo {
1300                                 channels: vec!(NetworkMap::get_key(5, zero_hash.clone()), NetworkMap::get_key(11, zero_hash.clone())),
1301                                 lowest_inbound_channel_fee_base_msat: 0,
1302                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1303                                 features: GlobalFeatures::new(),
1304                                 last_update: 1,
1305                                 rgb: [0; 3],
1306                                 alias: [0; 32],
1307                                 addresses: Vec::new(),
1308                                 announcement_message: None,
1309                         });
1310                         network.channels.insert(NetworkMap::get_key(5, zero_hash.clone()), ChannelInfo {
1311                                 features: GlobalFeatures::new(),
1312                                 one_to_two: DirectionalChannelInfo {
1313                                         src_node_id: node3.clone(),
1314                                         last_update: 0,
1315                                         enabled: true,
1316                                         cltv_expiry_delta: (5 << 8) | 1,
1317                                         htlc_minimum_msat: 0,
1318                                         fee_base_msat: 100,
1319                                         fee_proportional_millionths: 0,
1320                                         last_update_message: None,
1321                                 }, two_to_one: DirectionalChannelInfo {
1322                                         src_node_id: node4.clone(),
1323                                         last_update: 0,
1324                                         enabled: true,
1325                                         cltv_expiry_delta: (5 << 8) | 2,
1326                                         htlc_minimum_msat: 0,
1327                                         fee_base_msat: 0,
1328                                         fee_proportional_millionths: 0,
1329                                         last_update_message: None,
1330                                 },
1331                                 announcement_message: None,
1332                         });
1333                         network.nodes.insert(node5.clone(), NodeInfo {
1334                                 channels: vec!(NetworkMap::get_key(6, zero_hash.clone()), NetworkMap::get_key(11, zero_hash.clone())),
1335                                 lowest_inbound_channel_fee_base_msat: 0,
1336                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1337                                 features: GlobalFeatures::new(),
1338                                 last_update: 1,
1339                                 rgb: [0; 3],
1340                                 alias: [0; 32],
1341                                 addresses: Vec::new(),
1342                                 announcement_message: None,
1343                         });
1344                         network.channels.insert(NetworkMap::get_key(6, zero_hash.clone()), ChannelInfo {
1345                                 features: GlobalFeatures::new(),
1346                                 one_to_two: DirectionalChannelInfo {
1347                                         src_node_id: node3.clone(),
1348                                         last_update: 0,
1349                                         enabled: true,
1350                                         cltv_expiry_delta: (6 << 8) | 1,
1351                                         htlc_minimum_msat: 0,
1352                                         fee_base_msat: 0,
1353                                         fee_proportional_millionths: 0,
1354                                         last_update_message: None,
1355                                 }, two_to_one: DirectionalChannelInfo {
1356                                         src_node_id: node5.clone(),
1357                                         last_update: 0,
1358                                         enabled: true,
1359                                         cltv_expiry_delta: (6 << 8) | 2,
1360                                         htlc_minimum_msat: 0,
1361                                         fee_base_msat: 0,
1362                                         fee_proportional_millionths: 0,
1363                                         last_update_message: None,
1364                                 },
1365                                 announcement_message: None,
1366                         });
1367                         network.channels.insert(NetworkMap::get_key(11, zero_hash.clone()), ChannelInfo {
1368                                 features: GlobalFeatures::new(),
1369                                 one_to_two: DirectionalChannelInfo {
1370                                         src_node_id: node5.clone(),
1371                                         last_update: 0,
1372                                         enabled: true,
1373                                         cltv_expiry_delta: (11 << 8) | 1,
1374                                         htlc_minimum_msat: 0,
1375                                         fee_base_msat: 0,
1376                                         fee_proportional_millionths: 0,
1377                                         last_update_message: None,
1378                                 }, two_to_one: DirectionalChannelInfo {
1379                                         src_node_id: node4.clone(),
1380                                         last_update: 0,
1381                                         enabled: true,
1382                                         cltv_expiry_delta: (11 << 8) | 2,
1383                                         htlc_minimum_msat: 0,
1384                                         fee_base_msat: 0,
1385                                         fee_proportional_millionths: 0,
1386                                         last_update_message: None,
1387                                 },
1388                                 announcement_message: None,
1389                         });
1390                         network.nodes.insert(node6.clone(), NodeInfo {
1391                                 channels: vec!(NetworkMap::get_key(7, zero_hash.clone())),
1392                                 lowest_inbound_channel_fee_base_msat: 0,
1393                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1394                                 features: GlobalFeatures::new(),
1395                                 last_update: 1,
1396                                 rgb: [0; 3],
1397                                 alias: [0; 32],
1398                                 addresses: Vec::new(),
1399                                 announcement_message: None,
1400                         });
1401                         network.channels.insert(NetworkMap::get_key(7, zero_hash.clone()), ChannelInfo {
1402                                 features: GlobalFeatures::new(),
1403                                 one_to_two: DirectionalChannelInfo {
1404                                         src_node_id: node3.clone(),
1405                                         last_update: 0,
1406                                         enabled: true,
1407                                         cltv_expiry_delta: (7 << 8) | 1,
1408                                         htlc_minimum_msat: 0,
1409                                         fee_base_msat: 0,
1410                                         fee_proportional_millionths: 1000000,
1411                                         last_update_message: None,
1412                                 }, two_to_one: DirectionalChannelInfo {
1413                                         src_node_id: node6.clone(),
1414                                         last_update: 0,
1415                                         enabled: true,
1416                                         cltv_expiry_delta: (7 << 8) | 2,
1417                                         htlc_minimum_msat: 0,
1418                                         fee_base_msat: 0,
1419                                         fee_proportional_millionths: 0,
1420                                         last_update_message: None,
1421                                 },
1422                                 announcement_message: None,
1423                         });
1424                 }
1425
1426                 { // Simple route to 3 via 2
1427                         let route = router.get_route(&node3, None, &Vec::new(), 100, 42).unwrap();
1428                         assert_eq!(route.hops.len(), 2);
1429
1430                         assert_eq!(route.hops[0].pubkey, node2);
1431                         assert_eq!(route.hops[0].short_channel_id, 2);
1432                         assert_eq!(route.hops[0].fee_msat, 100);
1433                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1434
1435                         assert_eq!(route.hops[1].pubkey, node3);
1436                         assert_eq!(route.hops[1].short_channel_id, 4);
1437                         assert_eq!(route.hops[1].fee_msat, 100);
1438                         assert_eq!(route.hops[1].cltv_expiry_delta, 42);
1439                 }
1440
1441                 { // Route to 1 via 2 and 3 because our channel to 1 is disabled
1442                         let route = router.get_route(&node1, None, &Vec::new(), 100, 42).unwrap();
1443                         assert_eq!(route.hops.len(), 3);
1444
1445                         assert_eq!(route.hops[0].pubkey, node2);
1446                         assert_eq!(route.hops[0].short_channel_id, 2);
1447                         assert_eq!(route.hops[0].fee_msat, 200);
1448                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1449
1450                         assert_eq!(route.hops[1].pubkey, node3);
1451                         assert_eq!(route.hops[1].short_channel_id, 4);
1452                         assert_eq!(route.hops[1].fee_msat, 100);
1453                         assert_eq!(route.hops[1].cltv_expiry_delta, (3 << 8) | 2);
1454
1455                         assert_eq!(route.hops[2].pubkey, node1);
1456                         assert_eq!(route.hops[2].short_channel_id, 3);
1457                         assert_eq!(route.hops[2].fee_msat, 100);
1458                         assert_eq!(route.hops[2].cltv_expiry_delta, 42);
1459                 }
1460
1461                 { // If we specify a channel to node8, that overrides our local channel view and that gets used
1462                         let our_chans = vec![channelmanager::ChannelDetails {
1463                                 channel_id: [0; 32],
1464                                 short_channel_id: Some(42),
1465                                 remote_network_id: node8.clone(),
1466                                 channel_value_satoshis: 0,
1467                                 user_id: 0,
1468                         }];
1469                         let route = router.get_route(&node3, Some(&our_chans), &Vec::new(), 100, 42).unwrap();
1470                         assert_eq!(route.hops.len(), 2);
1471
1472                         assert_eq!(route.hops[0].pubkey, node8);
1473                         assert_eq!(route.hops[0].short_channel_id, 42);
1474                         assert_eq!(route.hops[0].fee_msat, 200);
1475                         assert_eq!(route.hops[0].cltv_expiry_delta, (13 << 8) | 1);
1476
1477                         assert_eq!(route.hops[1].pubkey, node3);
1478                         assert_eq!(route.hops[1].short_channel_id, 13);
1479                         assert_eq!(route.hops[1].fee_msat, 100);
1480                         assert_eq!(route.hops[1].cltv_expiry_delta, 42);
1481                 }
1482
1483                 let mut last_hops = vec!(RouteHint {
1484                                 src_node_id: node4.clone(),
1485                                 short_channel_id: 8,
1486                                 fee_base_msat: 0,
1487                                 fee_proportional_millionths: 0,
1488                                 cltv_expiry_delta: (8 << 8) | 1,
1489                                 htlc_minimum_msat: 0,
1490                         }, RouteHint {
1491                                 src_node_id: node5.clone(),
1492                                 short_channel_id: 9,
1493                                 fee_base_msat: 1001,
1494                                 fee_proportional_millionths: 0,
1495                                 cltv_expiry_delta: (9 << 8) | 1,
1496                                 htlc_minimum_msat: 0,
1497                         }, RouteHint {
1498                                 src_node_id: node6.clone(),
1499                                 short_channel_id: 10,
1500                                 fee_base_msat: 0,
1501                                 fee_proportional_millionths: 0,
1502                                 cltv_expiry_delta: (10 << 8) | 1,
1503                                 htlc_minimum_msat: 0,
1504                         });
1505
1506                 { // Simple test across 2, 3, 5, and 4 via a last_hop channel
1507                         let route = router.get_route(&node7, None, &last_hops, 100, 42).unwrap();
1508                         assert_eq!(route.hops.len(), 5);
1509
1510                         assert_eq!(route.hops[0].pubkey, node2);
1511                         assert_eq!(route.hops[0].short_channel_id, 2);
1512                         assert_eq!(route.hops[0].fee_msat, 100);
1513                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1514
1515                         assert_eq!(route.hops[1].pubkey, node3);
1516                         assert_eq!(route.hops[1].short_channel_id, 4);
1517                         assert_eq!(route.hops[1].fee_msat, 0);
1518                         assert_eq!(route.hops[1].cltv_expiry_delta, (6 << 8) | 1);
1519
1520                         assert_eq!(route.hops[2].pubkey, node5);
1521                         assert_eq!(route.hops[2].short_channel_id, 6);
1522                         assert_eq!(route.hops[2].fee_msat, 0);
1523                         assert_eq!(route.hops[2].cltv_expiry_delta, (11 << 8) | 1);
1524
1525                         assert_eq!(route.hops[3].pubkey, node4);
1526                         assert_eq!(route.hops[3].short_channel_id, 11);
1527                         assert_eq!(route.hops[3].fee_msat, 0);
1528                         assert_eq!(route.hops[3].cltv_expiry_delta, (8 << 8) | 1);
1529
1530                         assert_eq!(route.hops[4].pubkey, node7);
1531                         assert_eq!(route.hops[4].short_channel_id, 8);
1532                         assert_eq!(route.hops[4].fee_msat, 100);
1533                         assert_eq!(route.hops[4].cltv_expiry_delta, 42);
1534                 }
1535
1536                 { // Simple test with outbound channel to 4 to test that last_hops and first_hops connect
1537                         let our_chans = vec![channelmanager::ChannelDetails {
1538                                 channel_id: [0; 32],
1539                                 short_channel_id: Some(42),
1540                                 remote_network_id: node4.clone(),
1541                                 channel_value_satoshis: 0,
1542                                 user_id: 0,
1543                         }];
1544                         let route = router.get_route(&node7, Some(&our_chans), &last_hops, 100, 42).unwrap();
1545                         assert_eq!(route.hops.len(), 2);
1546
1547                         assert_eq!(route.hops[0].pubkey, node4);
1548                         assert_eq!(route.hops[0].short_channel_id, 42);
1549                         assert_eq!(route.hops[0].fee_msat, 0);
1550                         assert_eq!(route.hops[0].cltv_expiry_delta, (8 << 8) | 1);
1551
1552                         assert_eq!(route.hops[1].pubkey, node7);
1553                         assert_eq!(route.hops[1].short_channel_id, 8);
1554                         assert_eq!(route.hops[1].fee_msat, 100);
1555                         assert_eq!(route.hops[1].cltv_expiry_delta, 42);
1556                 }
1557
1558                 last_hops[0].fee_base_msat = 1000;
1559
1560                 { // Revert to via 6 as the fee on 8 goes up
1561                         let route = router.get_route(&node7, None, &last_hops, 100, 42).unwrap();
1562                         assert_eq!(route.hops.len(), 4);
1563
1564                         assert_eq!(route.hops[0].pubkey, node2);
1565                         assert_eq!(route.hops[0].short_channel_id, 2);
1566                         assert_eq!(route.hops[0].fee_msat, 200); // fee increased as its % of value transferred across node
1567                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1568
1569                         assert_eq!(route.hops[1].pubkey, node3);
1570                         assert_eq!(route.hops[1].short_channel_id, 4);
1571                         assert_eq!(route.hops[1].fee_msat, 100);
1572                         assert_eq!(route.hops[1].cltv_expiry_delta, (7 << 8) | 1);
1573
1574                         assert_eq!(route.hops[2].pubkey, node6);
1575                         assert_eq!(route.hops[2].short_channel_id, 7);
1576                         assert_eq!(route.hops[2].fee_msat, 0);
1577                         assert_eq!(route.hops[2].cltv_expiry_delta, (10 << 8) | 1);
1578
1579                         assert_eq!(route.hops[3].pubkey, node7);
1580                         assert_eq!(route.hops[3].short_channel_id, 10);
1581                         assert_eq!(route.hops[3].fee_msat, 100);
1582                         assert_eq!(route.hops[3].cltv_expiry_delta, 42);
1583                 }
1584
1585                 { // ...but still use 8 for larger payments as 6 has a variable feerate
1586                         let route = router.get_route(&node7, None, &last_hops, 2000, 42).unwrap();
1587                         assert_eq!(route.hops.len(), 5);
1588
1589                         assert_eq!(route.hops[0].pubkey, node2);
1590                         assert_eq!(route.hops[0].short_channel_id, 2);
1591                         assert_eq!(route.hops[0].fee_msat, 3000);
1592                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1593
1594                         assert_eq!(route.hops[1].pubkey, node3);
1595                         assert_eq!(route.hops[1].short_channel_id, 4);
1596                         assert_eq!(route.hops[1].fee_msat, 0);
1597                         assert_eq!(route.hops[1].cltv_expiry_delta, (6 << 8) | 1);
1598
1599                         assert_eq!(route.hops[2].pubkey, node5);
1600                         assert_eq!(route.hops[2].short_channel_id, 6);
1601                         assert_eq!(route.hops[2].fee_msat, 0);
1602                         assert_eq!(route.hops[2].cltv_expiry_delta, (11 << 8) | 1);
1603
1604                         assert_eq!(route.hops[3].pubkey, node4);
1605                         assert_eq!(route.hops[3].short_channel_id, 11);
1606                         assert_eq!(route.hops[3].fee_msat, 1000);
1607                         assert_eq!(route.hops[3].cltv_expiry_delta, (8 << 8) | 1);
1608
1609                         assert_eq!(route.hops[4].pubkey, node7);
1610                         assert_eq!(route.hops[4].short_channel_id, 8);
1611                         assert_eq!(route.hops[4].fee_msat, 2000);
1612                         assert_eq!(route.hops[4].cltv_expiry_delta, 42);
1613                 }
1614
1615                 { // Test Router serialization/deserialization
1616                         let mut w = TestVecWriter(Vec::new());
1617                         let network = router.network_map.read().unwrap();
1618                         assert!(!network.channels.is_empty());
1619                         assert!(!network.nodes.is_empty());
1620                         network.write(&mut w).unwrap();
1621                         assert!(<NetworkMap>::read(&mut ::std::io::Cursor::new(&w.0)).unwrap() == *network);
1622                 }
1623         }
1624 }