_ Git - rust-lightning/blob - lightning/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;
   8 use secp256k1;
   9
  10 use bitcoin_hashes::sha256d::Hash as Sha256dHash;
  11 use bitcoin_hashes::Hash;
  12 use bitcoin::blockdata::script::Builder;
  13 use bitcoin::blockdata::opcodes;
  14
  15 use chain::chaininterface::{ChainError, ChainWatchInterface};
  16 use ln::channelmanager;
  17 use ln::msgs::{DecodeError,ErrorAction,LightningError,RoutingMessageHandler,NetAddress,ChannelFeatures,NodeFeatures};
  18 use ln::msgs;
  19 use util::ser::{Writeable, Readable, Writer, ReadableArgs};
  20 use util::logger::Logger;
  21
  22 use std::cmp;
  23 use std::sync::{RwLock,Arc};
  24 use std::collections::{HashMap,BinaryHeap,BTreeMap};
  25 use std::collections::btree_map::Entry as BtreeEntry;
  26 use std;
  27
  28 /// A hop in a route
  29 #[derive(Clone, PartialEq)]
  30 pub struct RouteHop {
  31         /// The node_id of the node at this hop.
  32         pub pubkey: PublicKey,
  33         /// The channel that should be used from the previous hop to reach this node.
  34         pub short_channel_id: u64,
  35         /// The fee taken on this hop. For the last hop, this should be the full value of the payment.
  36         pub fee_msat: u64,
  37         /// The CLTV delta added for this hop. For the last hop, this should be the full CLTV value
  38         /// expected at the destination, in excess of the current block height.
  39         pub cltv_expiry_delta: u32,
  40 }
  41
  42 /// A route from us through the network to a destination
  43 #[derive(Clone, PartialEq)]
  44 pub struct Route {
  45         /// The list of hops, NOT INCLUDING our own, where the last hop is the destination. Thus, this
  46         /// must always be at least length one. By protocol rules, this may not currently exceed 20 in
  47         /// length.
  48         pub hops: Vec<RouteHop>,
  49 }
  50
  51 impl Writeable for Route {
  52         fn write<W: ::util::ser::Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
  53                 (self.hops.len() as u8).write(writer)?;
  54                 for hop in self.hops.iter() {
  55                         hop.pubkey.write(writer)?;
  56                         hop.short_channel_id.write(writer)?;
  57                         hop.fee_msat.write(writer)?;
  58                         hop.cltv_expiry_delta.write(writer)?;
  59                 }
  60                 Ok(())
  61         }
  62 }
  63
  64 impl<R: ::std::io::Read> Readable<R> for Route {
  65         fn read(reader: &mut R) -> Result<Route, DecodeError> {
  66                 let hops_count: u8 = Readable::read(reader)?;
  67                 let mut hops = Vec::with_capacity(hops_count as usize);
  68                 for _ in 0..hops_count {
  69                         hops.push(RouteHop {
  70                                 pubkey: Readable::read(reader)?,
  71                                 short_channel_id: Readable::read(reader)?,
  72                                 fee_msat: Readable::read(reader)?,
  73                                 cltv_expiry_delta: Readable::read(reader)?,
  74                         });
  75                 }
  76                 Ok(Route {
  77                         hops
  78                 })
  79         }
  80 }
  81
  82 #[derive(PartialEq)]
  83 struct DirectionalChannelInfo {
  84         src_node_id: PublicKey,
  85         last_update: u32,
  86         enabled: bool,
  87         cltv_expiry_delta: u16,
  88         htlc_minimum_msat: u64,
  89         fee_base_msat: u32,
  90         fee_proportional_millionths: u32,
  91         last_update_message: Option<msgs::ChannelUpdate>,
  92 }
  93
  94 impl std::fmt::Display for DirectionalChannelInfo {
  95         fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
  96                 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)?;
  97                 Ok(())
  98         }
  99 }
 100
 101 impl_writeable!(DirectionalChannelInfo, 0, {
 102         src_node_id,
 103         last_update,
 104         enabled,
 105         cltv_expiry_delta,
 106         htlc_minimum_msat,
 107         fee_base_msat,
 108         fee_proportional_millionths,
 109         last_update_message
 110 });
 111
 112 #[derive(PartialEq)]
 113 struct ChannelInfo {
 114         features: ChannelFeatures,
 115         one_to_two: DirectionalChannelInfo,
 116         two_to_one: DirectionalChannelInfo,
 117         //this is cached here so we can send out it later if required by route_init_sync
 118         //keep an eye on this to see if the extra memory is a problem
 119         announcement_message: Option<msgs::ChannelAnnouncement>,
 120 }
 121
 122 impl std::fmt::Display for ChannelInfo {
 123         fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
 124                 write!(f, "features: {}, one_to_two: {}, two_to_one: {}", log_bytes!(self.features.encode()), self.one_to_two, self.two_to_one)?;
 125                 Ok(())
 126         }
 127 }
 128
 129 impl_writeable!(ChannelInfo, 0, {
 130         features,
 131         one_to_two,
 132         two_to_one,
 133         announcement_message
 134 });
 135
 136 #[derive(PartialEq)]
 137 struct NodeInfo {
 138         #[cfg(feature = "non_bitcoin_chain_hash_routing")]
 139         channels: Vec<(u64, Sha256dHash)>,
 140         #[cfg(not(feature = "non_bitcoin_chain_hash_routing"))]
 141         channels: Vec<u64>,
 142
 143         lowest_inbound_channel_fee_base_msat: u32,
 144         lowest_inbound_channel_fee_proportional_millionths: u32,
 145
 146         features: NodeFeatures,
 147         last_update: u32,
 148         rgb: [u8; 3],
 149         alias: [u8; 32],
 150         addresses: Vec<NetAddress>,
 151         //this is cached here so we can send out it later if required by route_init_sync
 152         //keep an eye on this to see if the extra memory is a problem
 153         announcement_message: Option<msgs::NodeAnnouncement>,
 154 }
 155
 156 impl std::fmt::Display for NodeInfo {
 157         fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
 158                 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[..])?;
 159                 Ok(())
 160         }
 161 }
 162
 163 impl Writeable for NodeInfo {
 164         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 165                 (self.channels.len() as u64).write(writer)?;
 166                 for ref chan in self.channels.iter() {
 167                         chan.write(writer)?;
 168                 }
 169                 self.lowest_inbound_channel_fee_base_msat.write(writer)?;
 170                 self.lowest_inbound_channel_fee_proportional_millionths.write(writer)?;
 171                 self.features.write(writer)?;
 172                 self.last_update.write(writer)?;
 173                 self.rgb.write(writer)?;
 174                 self.alias.write(writer)?;
 175                 (self.addresses.len() as u64).write(writer)?;
 176                 for ref addr in &self.addresses {
 177                         addr.write(writer)?;
 178                 }
 179                 self.announcement_message.write(writer)?;
 180                 Ok(())
 181         }
 182 }
 183
 184 const MAX_ALLOC_SIZE: u64 = 64*1024;
 185
 186 impl<R: ::std::io::Read> Readable<R> for NodeInfo {
 187         fn read(reader: &mut R) -> Result<NodeInfo, DecodeError> {
 188                 let channels_count: u64 = Readable::read(reader)?;
 189                 let mut channels = Vec::with_capacity(cmp::min(channels_count, MAX_ALLOC_SIZE / 8) as usize);
 190                 for _ in 0..channels_count {
 191                         channels.push(Readable::read(reader)?);
 192                 }
 193                 let lowest_inbound_channel_fee_base_msat = Readable::read(reader)?;
 194                 let lowest_inbound_channel_fee_proportional_millionths = Readable::read(reader)?;
 195                 let features = Readable::read(reader)?;
 196                 let last_update = Readable::read(reader)?;
 197                 let rgb = Readable::read(reader)?;
 198                 let alias = Readable::read(reader)?;
 199                 let addresses_count: u64 = Readable::read(reader)?;
 200                 let mut addresses = Vec::with_capacity(cmp::min(addresses_count, MAX_ALLOC_SIZE / 40) as usize);
 201                 for _ in 0..addresses_count {
 202                         match Readable::read(reader) {
 203                                 Ok(Ok(addr)) => { addresses.push(addr); },
 204                                 Ok(Err(_)) => return Err(DecodeError::InvalidValue),
 205                                 Err(DecodeError::ShortRead) => return Err(DecodeError::BadLengthDescriptor),
 206                                 _ => unreachable!(),
 207                         }
 208                 }
 209                 let announcement_message = Readable::read(reader)?;
 210                 Ok(NodeInfo {
 211                         channels,
 212                         lowest_inbound_channel_fee_base_msat,
 213                         lowest_inbound_channel_fee_proportional_millionths,
 214                         features,
 215                         last_update,
 216                         rgb,
 217                         alias,
 218                         addresses,
 219                         announcement_message
 220                 })
 221         }
 222 }
 223
 224 #[derive(PartialEq)]
 225 struct NetworkMap {
 226         #[cfg(feature = "non_bitcoin_chain_hash_routing")]
 227         channels: BTreeMap<(u64, Sha256dHash), ChannelInfo>,
 228         #[cfg(not(feature = "non_bitcoin_chain_hash_routing"))]
 229         channels: BTreeMap<u64, ChannelInfo>,
 230
 231         our_node_id: PublicKey,
 232         nodes: BTreeMap<PublicKey, NodeInfo>,
 233 }
 234
 235 impl Writeable for NetworkMap {
 236         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 237                 (self.channels.len() as u64).write(writer)?;
 238                 for (ref chan_id, ref chan_info) in self.channels.iter() {
 239                         (*chan_id).write(writer)?;
 240                         chan_info.write(writer)?;
 241                 }
 242                 self.our_node_id.write(writer)?;
 243                 (self.nodes.len() as u64).write(writer)?;
 244                 for (ref node_id, ref node_info) in self.nodes.iter() {
 245                         node_id.write(writer)?;
 246                         node_info.write(writer)?;
 247                 }
 248                 Ok(())
 249         }
 250 }
 251
 252 impl<R: ::std::io::Read> Readable<R> for NetworkMap {
 253         fn read(reader: &mut R) -> Result<NetworkMap, DecodeError> {
 254                 let channels_count: u64 = Readable::read(reader)?;
 255                 let mut channels = BTreeMap::new();
 256                 for _ in 0..channels_count {
 257                         let chan_id: u64 = Readable::read(reader)?;
 258                         let chan_info = Readable::read(reader)?;
 259                         channels.insert(chan_id, chan_info);
 260                 }
 261                 let our_node_id = Readable::read(reader)?;
 262                 let nodes_count: u64 = Readable::read(reader)?;
 263                 let mut nodes = BTreeMap::new();
 264                 for _ in 0..nodes_count {
 265                         let node_id = Readable::read(reader)?;
 266                         let node_info = Readable::read(reader)?;
 267                         nodes.insert(node_id, node_info);
 268                 }
 269                 Ok(NetworkMap {
 270                         channels,
 271                         our_node_id,
 272                         nodes,
 273                 })
 274         }
 275 }
 276
 277 struct MutNetworkMap<'a> {
 278         #[cfg(feature = "non_bitcoin_chain_hash_routing")]
 279         channels: &'a mut BTreeMap<(u64, Sha256dHash), ChannelInfo>,
 280         #[cfg(not(feature = "non_bitcoin_chain_hash_routing"))]
 281         channels: &'a mut BTreeMap<u64, ChannelInfo>,
 282         nodes: &'a mut BTreeMap<PublicKey, NodeInfo>,
 283 }
 284 impl NetworkMap {
 285         fn borrow_parts(&mut self) -> MutNetworkMap {
 286                 MutNetworkMap {
 287                         channels: &mut self.channels,
 288                         nodes: &mut self.nodes,
 289                 }
 290         }
 291 }
 292 impl std::fmt::Display for NetworkMap {
 293         fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
 294                 write!(f, "Node id {} network map\n[Channels]\n", log_pubkey!(self.our_node_id))?;
 295                 for (key, val) in self.channels.iter() {
 296                         write!(f, " {}: {}\n", key, val)?;
 297                 }
 298                 write!(f, "[Nodes]\n")?;
 299                 for (key, val) in self.nodes.iter() {
 300                         write!(f, " {}: {}\n", log_pubkey!(key), val)?;
 301                 }
 302                 Ok(())
 303         }
 304 }
 305
 306 impl NetworkMap {
 307         #[cfg(feature = "non_bitcoin_chain_hash_routing")]
 308         #[inline]
 309         fn get_key(short_channel_id: u64, chain_hash: Sha256dHash) -> (u64, Sha256dHash) {
 310                 (short_channel_id, chain_hash)
 311         }
 312
 313         #[cfg(not(feature = "non_bitcoin_chain_hash_routing"))]
 314         #[inline]
 315         fn get_key(short_channel_id: u64, _: Sha256dHash) -> u64 {
 316                 short_channel_id
 317         }
 318
 319         #[cfg(feature = "non_bitcoin_chain_hash_routing")]
 320         #[inline]
 321         fn get_short_id(id: &(u64, Sha256dHash)) -> &u64 {
 322                 &id.0
 323         }
 324
 325         #[cfg(not(feature = "non_bitcoin_chain_hash_routing"))]
 326         #[inline]
 327         fn get_short_id(id: &u64) -> &u64 {
 328                 id
 329         }
 330 }
 331
 332 /// A channel descriptor which provides a last-hop route to get_route
 333 pub struct RouteHint {
 334         /// The node_id of the non-target end of the route
 335         pub src_node_id: PublicKey,
 336         /// The short_channel_id of this channel
 337         pub short_channel_id: u64,
 338         /// The static msat-denominated fee which must be paid to use this channel
 339         pub fee_base_msat: u32,
 340         /// The dynamic proportional fee which must be paid to use this channel, denominated in
 341         /// millionths of the value being forwarded to the next hop.
 342         pub fee_proportional_millionths: u32,
 343         /// The difference in CLTV values between this node and the next node.
 344         pub cltv_expiry_delta: u16,
 345         /// The minimum value, in msat, which must be relayed to the next hop.
 346         pub htlc_minimum_msat: u64,
 347 }
 348
 349 /// Tracks a view of the network, receiving updates from peers and generating Routes to
 350 /// payment destinations.
 351 pub struct Router {
 352         secp_ctx: Secp256k1<secp256k1::VerifyOnly>,
 353         network_map: RwLock<NetworkMap>,
 354         chain_monitor: Arc<ChainWatchInterface>,
 355         logger: Arc<Logger>,
 356 }
 357
 358 const SERIALIZATION_VERSION: u8 = 1;
 359 const MIN_SERIALIZATION_VERSION: u8 = 1;
 360
 361 impl Writeable for Router {
 362         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 363                 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
 364                 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
 365
 366                 let network = self.network_map.read().unwrap();
 367                 network.write(writer)?;
 368                 Ok(())
 369         }
 370 }
 371
 372 /// Arguments for the creation of a Router that are not deserialized.
 373 /// At a high-level, the process for deserializing a Router and resuming normal operation is:
 374 /// 1) Deserialize the Router by filling in this struct and calling <Router>::read(reaser, args).
 375 /// 2) Register the new Router with your ChainWatchInterface
 376 pub struct RouterReadArgs {
 377         /// The ChainWatchInterface for use in the Router in the future.
 378         ///
 379         /// No calls to the ChainWatchInterface will be made during deserialization.
 380         pub chain_monitor: Arc<ChainWatchInterface>,
 381         /// The Logger for use in the ChannelManager and which may be used to log information during
 382         /// deserialization.
 383         pub logger: Arc<Logger>,
 384 }
 385
 386 impl<R: ::std::io::Read> ReadableArgs<R, RouterReadArgs> for Router {
 387         fn read(reader: &mut R, args: RouterReadArgs) -> Result<Router, DecodeError> {
 388                 let _ver: u8 = Readable::read(reader)?;
 389                 let min_ver: u8 = Readable::read(reader)?;
 390                 if min_ver > SERIALIZATION_VERSION {
 391                         return Err(DecodeError::UnknownVersion);
 392                 }
 393                 let network_map = Readable::read(reader)?;
 394                 Ok(Router {
 395                         secp_ctx: Secp256k1::verification_only(),
 396                         network_map: RwLock::new(network_map),
 397                         chain_monitor: args.chain_monitor,
 398                         logger: args.logger,
 399                 })
 400         }
 401 }
 402
 403 macro_rules! secp_verify_sig {
 404         ( $secp_ctx: expr, $msg: expr, $sig: expr, $pubkey: expr ) => {
 405                 match $secp_ctx.verify($msg, $sig, $pubkey) {
 406                         Ok(_) => {},
 407                         Err(_) => return Err(LightningError{err: "Invalid signature from remote node", action: ErrorAction::IgnoreError}),
 408                 }
 409         };
 410 }
 411
 412 impl RoutingMessageHandler for Router {
 413         fn handle_node_announcement(&self, msg: &msgs::NodeAnnouncement) -> Result<bool, LightningError> {
 414                 let msg_hash = hash_to_message!(&Sha256dHash::hash(&msg.contents.encode()[..])[..]);
 415                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.signature, &msg.contents.node_id);
 416
 417                 let mut network = self.network_map.write().unwrap();
 418                 match network.nodes.get_mut(&msg.contents.node_id) {
 419                         None => Err(LightningError{err: "No existing channels for node_announcement", action: ErrorAction::IgnoreError}),
 420                         Some(node) => {
 421                                 if node.last_update >= msg.contents.timestamp {
 422                                         return Err(LightningError{err: "Update older than last processed update", action: ErrorAction::IgnoreError});
 423                                 }
 424
 425                                 node.features = msg.contents.features.clone();
 426                                 node.last_update = msg.contents.timestamp;
 427                                 node.rgb = msg.contents.rgb;
 428                                 node.alias = msg.contents.alias;
 429                                 node.addresses = msg.contents.addresses.clone();
 430
 431                                 let should_relay = msg.contents.excess_data.is_empty() && msg.contents.excess_address_data.is_empty();
 432                                 node.announcement_message = if should_relay { Some(msg.clone()) } else { None };
 433                                 Ok(should_relay)
 434                         }
 435                 }
 436         }
 437
 438         fn handle_channel_announcement(&self, msg: &msgs::ChannelAnnouncement) -> Result<bool, LightningError> {
 439                 if msg.contents.node_id_1 == msg.contents.node_id_2 || msg.contents.bitcoin_key_1 == msg.contents.bitcoin_key_2 {
 440                         return Err(LightningError{err: "Channel announcement node had a channel with itself", action: ErrorAction::IgnoreError});
 441                 }
 442
 443                 let msg_hash = hash_to_message!(&Sha256dHash::hash(&msg.contents.encode()[..])[..]);
 444                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.node_signature_1, &msg.contents.node_id_1);
 445                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.node_signature_2, &msg.contents.node_id_2);
 446                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.bitcoin_signature_1, &msg.contents.bitcoin_key_1);
 447                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.bitcoin_signature_2, &msg.contents.bitcoin_key_2);
 448
 449                 let checked_utxo = match self.chain_monitor.get_chain_utxo(msg.contents.chain_hash, msg.contents.short_channel_id) {
 450                         Ok((script_pubkey, _value)) => {
 451                                 let expected_script = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
 452                                                                     .push_slice(&msg.contents.bitcoin_key_1.serialize())
 453                                                                     .push_slice(&msg.contents.bitcoin_key_2.serialize())
 454                                                                     .push_opcode(opcodes::all::OP_PUSHNUM_2)
 455                                                                     .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
 456                                 if script_pubkey != expected_script {
 457                                         return Err(LightningError{err: "Channel announcement keys didn't match on-chain script", action: ErrorAction::IgnoreError});
 458                                 }
 459                                 //TODO: Check if value is worth storing, use it to inform routing, and compare it
 460                                 //to the new HTLC max field in channel_update
 461                                 true
 462                         },
 463                         Err(ChainError::NotSupported) => {
 464                                 // Tentatively accept, potentially exposing us to DoS attacks
 465                                 false
 466                         },
 467                         Err(ChainError::NotWatched) => {
 468                                 return Err(LightningError{err: "Channel announced on an unknown chain", action: ErrorAction::IgnoreError});
 469                         },
 470                         Err(ChainError::UnknownTx) => {
 471                                 return Err(LightningError{err: "Channel announced without corresponding UTXO entry", action: ErrorAction::IgnoreError});
 472                         },
 473                 };
 474
 475                 let mut network_lock = self.network_map.write().unwrap();
 476                 let network = network_lock.borrow_parts();
 477
 478                 let should_relay = msg.contents.excess_data.is_empty();
 479
 480                 let chan_info = ChannelInfo {
 481                                 features: msg.contents.features.clone(),
 482                                 one_to_two: DirectionalChannelInfo {
 483                                         src_node_id: msg.contents.node_id_1.clone(),
 484                                         last_update: 0,
 485                                         enabled: false,
 486                                         cltv_expiry_delta: u16::max_value(),
 487                                         htlc_minimum_msat: u64::max_value(),
 488                                         fee_base_msat: u32::max_value(),
 489                                         fee_proportional_millionths: u32::max_value(),
 490                                         last_update_message: None,
 491                                 },
 492                                 two_to_one: DirectionalChannelInfo {
 493                                         src_node_id: msg.contents.node_id_2.clone(),
 494                                         last_update: 0,
 495                                         enabled: false,
 496                                         cltv_expiry_delta: u16::max_value(),
 497                                         htlc_minimum_msat: u64::max_value(),
 498                                         fee_base_msat: u32::max_value(),
 499                                         fee_proportional_millionths: u32::max_value(),
 500                                         last_update_message: None,
 501                                 },
 502                                 announcement_message: if should_relay { Some(msg.clone()) } else { None },
 503                         };
 504
 505                 match network.channels.entry(NetworkMap::get_key(msg.contents.short_channel_id, msg.contents.chain_hash)) {
 506                         BtreeEntry::Occupied(mut entry) => {
 507                                 //TODO: because asking the blockchain if short_channel_id is valid is only optional
 508                                 //in the blockchain API, we need to handle it smartly here, though it's unclear
 509                                 //exactly how...
 510                                 if checked_utxo {
 511                                         // Either our UTXO provider is busted, there was a reorg, or the UTXO provider
 512                                         // only sometimes returns results. In any case remove the previous entry. Note
 513                                         // that the spec expects us to "blacklist" the node_ids involved, but we can't
 514                                         // do that because
 515                                         // a) we don't *require* a UTXO provider that always returns results.
 516                                         // b) we don't track UTXOs of channels we know about and remove them if they
 517                                         //    get reorg'd out.
 518                                         // c) it's unclear how to do so without exposing ourselves to massive DoS risk.
 519                                         Self::remove_channel_in_nodes(network.nodes, &entry.get(), msg.contents.short_channel_id);
 520                                         *entry.get_mut() = chan_info;
 521                                 } else {
 522                                         return Err(LightningError{err: "Already have knowledge of channel", action: ErrorAction::IgnoreError})
 523                                 }
 524                         },
 525                         BtreeEntry::Vacant(entry) => {
 526                                 entry.insert(chan_info);
 527                         }
 528                 };
 529
 530                 macro_rules! add_channel_to_node {
 531                         ( $node_id: expr ) => {
 532                                 match network.nodes.entry($node_id) {
 533                                         BtreeEntry::Occupied(node_entry) => {
 534                                                 node_entry.into_mut().channels.push(NetworkMap::get_key(msg.contents.short_channel_id, msg.contents.chain_hash));
 535                                         },
 536                                         BtreeEntry::Vacant(node_entry) => {
 537                                                 node_entry.insert(NodeInfo {
 538                                                         channels: vec!(NetworkMap::get_key(msg.contents.short_channel_id, msg.contents.chain_hash)),
 539                                                         lowest_inbound_channel_fee_base_msat: u32::max_value(),
 540                                                         lowest_inbound_channel_fee_proportional_millionths: u32::max_value(),
 541                                                         features: NodeFeatures::empty(),
 542                                                         last_update: 0,
 543                                                         rgb: [0; 3],
 544                                                         alias: [0; 32],
 545                                                         addresses: Vec::new(),
 546                                                         announcement_message: None,
 547                                                 });
 548                                         }
 549                                 }
 550                         };
 551                 }
 552
 553                 add_channel_to_node!(msg.contents.node_id_1);
 554                 add_channel_to_node!(msg.contents.node_id_2);
 555
 556                 Ok(should_relay)
 557         }
 558
 559         fn handle_htlc_fail_channel_update(&self, update: &msgs::HTLCFailChannelUpdate) {
 560                 match update {
 561                         &msgs::HTLCFailChannelUpdate::ChannelUpdateMessage { ref msg } => {
 562                                 let _ = self.handle_channel_update(msg);
 563                         },
 564                         &msgs::HTLCFailChannelUpdate::ChannelClosed { ref short_channel_id, ref is_permanent } => {
 565                                 let mut network = self.network_map.write().unwrap();
 566                                 if *is_permanent {
 567                                         if let Some(chan) = network.channels.remove(short_channel_id) {
 568                                                 Self::remove_channel_in_nodes(&mut network.nodes, &chan, *short_channel_id);
 569                                         }
 570                                 } else {
 571                                         if let Some(chan) = network.channels.get_mut(short_channel_id) {
 572                                                 chan.one_to_two.enabled = false;
 573                                                 chan.two_to_one.enabled = false;
 574                                         }
 575                                 }
 576                         },
 577                         &msgs::HTLCFailChannelUpdate::NodeFailure { ref node_id, ref is_permanent } => {
 578                                 if *is_permanent {
 579                                         //TODO: Wholly remove the node
 580                                 } else {
 581                                         self.mark_node_bad(node_id, false);
 582                                 }
 583                         },
 584                 }
 585         }
 586
 587         fn handle_channel_update(&self, msg: &msgs::ChannelUpdate) -> Result<bool, LightningError> {
 588                 let mut network = self.network_map.write().unwrap();
 589                 let dest_node_id;
 590                 let chan_enabled = msg.contents.flags & (1 << 1) != (1 << 1);
 591                 let chan_was_enabled;
 592
 593                 match network.channels.get_mut(&NetworkMap::get_key(msg.contents.short_channel_id, msg.contents.chain_hash)) {
 594                         None => return Err(LightningError{err: "Couldn't find channel for update", action: ErrorAction::IgnoreError}),
 595                         Some(channel) => {
 596                                 macro_rules! maybe_update_channel_info {
 597                                         ( $target: expr) => {
 598                                                 if $target.last_update >= msg.contents.timestamp {
 599                                                         return Err(LightningError{err: "Update older than last processed update", action: ErrorAction::IgnoreError});
 600                                                 }
 601                                                 chan_was_enabled = $target.enabled;
 602                                                 $target.last_update = msg.contents.timestamp;
 603                                                 $target.enabled = chan_enabled;
 604                                                 $target.cltv_expiry_delta = msg.contents.cltv_expiry_delta;
 605                                                 $target.htlc_minimum_msat = msg.contents.htlc_minimum_msat;
 606                                                 $target.fee_base_msat = msg.contents.fee_base_msat;
 607                                                 $target.fee_proportional_millionths = msg.contents.fee_proportional_millionths;
 608                                                 $target.last_update_message = if msg.contents.excess_data.is_empty() {
 609                                                         Some(msg.clone())
 610                                                 } else {
 611                                                         None
 612                                                 };
 613                                         }
 614                                 }
 615                                 let msg_hash = hash_to_message!(&Sha256dHash::hash(&msg.contents.encode()[..])[..]);
 616                                 if msg.contents.flags & 1 == 1 {
 617                                         dest_node_id = channel.one_to_two.src_node_id.clone();
 618                                         secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.signature, &channel.two_to_one.src_node_id);
 619                                         maybe_update_channel_info!(channel.two_to_one);
 620                                 } else {
 621                                         dest_node_id = channel.two_to_one.src_node_id.clone();
 622                                         secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.signature, &channel.one_to_two.src_node_id);
 623                                         maybe_update_channel_info!(channel.one_to_two);
 624                                 }
 625                         }
 626                 }
 627
 628                 if chan_enabled {
 629                         let node = network.nodes.get_mut(&dest_node_id).unwrap();
 630                         node.lowest_inbound_channel_fee_base_msat = cmp::min(node.lowest_inbound_channel_fee_base_msat, msg.contents.fee_base_msat);
 631                         node.lowest_inbound_channel_fee_proportional_millionths = cmp::min(node.lowest_inbound_channel_fee_proportional_millionths, msg.contents.fee_proportional_millionths);
 632                 } else if chan_was_enabled {
 633                         let mut lowest_inbound_channel_fee_base_msat = u32::max_value();
 634                         let mut lowest_inbound_channel_fee_proportional_millionths = u32::max_value();
 635
 636                         {
 637                                 let node = network.nodes.get(&dest_node_id).unwrap();
 638
 639                                 for chan_id in node.channels.iter() {
 640                                         let chan = network.channels.get(chan_id).unwrap();
 641                                         if chan.one_to_two.src_node_id == dest_node_id {
 642                                                 lowest_inbound_channel_fee_base_msat = cmp::min(lowest_inbound_channel_fee_base_msat, chan.two_to_one.fee_base_msat);
 643                                                 lowest_inbound_channel_fee_proportional_millionths = cmp::min(lowest_inbound_channel_fee_proportional_millionths, chan.two_to_one.fee_proportional_millionths);
 644                                         } else {
 645                                                 lowest_inbound_channel_fee_base_msat = cmp::min(lowest_inbound_channel_fee_base_msat, chan.one_to_two.fee_base_msat);
 646                                                 lowest_inbound_channel_fee_proportional_millionths = cmp::min(lowest_inbound_channel_fee_proportional_millionths, chan.one_to_two.fee_proportional_millionths);
 647                                         }
 648                                 }
 649                         }
 650
 651                         //TODO: satisfy the borrow-checker without a double-map-lookup :(
 652                         let mut_node = network.nodes.get_mut(&dest_node_id).unwrap();
 653                         mut_node.lowest_inbound_channel_fee_base_msat = lowest_inbound_channel_fee_base_msat;
 654                         mut_node.lowest_inbound_channel_fee_proportional_millionths = lowest_inbound_channel_fee_proportional_millionths;
 655                 }
 656
 657                 Ok(msg.contents.excess_data.is_empty())
 658         }
 659
 660
 661         fn get_next_channel_announcements(&self, starting_point: u64, batch_amount: u8) -> Vec<(msgs::ChannelAnnouncement, msgs::ChannelUpdate,msgs::ChannelUpdate)> {
 662                 let mut result = Vec::with_capacity(batch_amount as usize);
 663                 let network = self.network_map.read().unwrap();
 664                 let mut iter = network.channels.range(starting_point..);
 665                 while result.len() < batch_amount as usize {
 666                         if let Some((_, ref chan)) = iter.next() {
 667                                 if chan.announcement_message.is_some() &&
 668                                                 chan.one_to_two.last_update_message.is_some() &&
 669                                                 chan.two_to_one.last_update_message.is_some() {
 670                                         result.push((chan.announcement_message.clone().unwrap(),
 671                                                 chan.one_to_two.last_update_message.clone().unwrap(),
 672                                                 chan.two_to_one.last_update_message.clone().unwrap()));
 673                                 } else {
 674                                         // TODO: We may end up sending un-announced channel_updates if we are sending
 675                                         // initial sync data while receiving announce/updates for this channel.
 676                                 }
 677                         } else {
 678                                 return result;
 679                         }
 680                 }
 681                 result
 682         }
 683
 684         fn get_next_node_announcements(&self, starting_point: Option<&PublicKey>, batch_amount: u8) -> Vec<msgs::NodeAnnouncement> {
 685                 let mut result = Vec::with_capacity(batch_amount as usize);
 686                 let network = self.network_map.read().unwrap();
 687                 let mut iter = if let Some(pubkey) = starting_point {
 688                                 let mut iter = network.nodes.range((*pubkey)..);
 689                                 iter.next();
 690                                 iter
 691                         } else {
 692                                 network.nodes.range(..)
 693                         };
 694                 while result.len() < batch_amount as usize {
 695                         if let Some((_, ref node)) = iter.next() {
 696                                 if node.announcement_message.is_some() {
 697                                         result.push(node.announcement_message.clone().unwrap());
 698                                 }
 699                         } else {
 700                                 return result;
 701                         }
 702                 }
 703                 result
 704         }
 705 }
 706
 707 #[derive(Eq, PartialEq)]
 708 struct RouteGraphNode {
 709         pubkey: PublicKey,
 710         lowest_fee_to_peer_through_node: u64,
 711         lowest_fee_to_node: u64,
 712 }
 713
 714 impl cmp::Ord for RouteGraphNode {
 715         fn cmp(&self, other: &RouteGraphNode) -> cmp::Ordering {
 716                 other.lowest_fee_to_peer_through_node.cmp(&self.lowest_fee_to_peer_through_node)
 717                         .then_with(|| other.pubkey.serialize().cmp(&self.pubkey.serialize()))
 718         }
 719 }
 720
 721 impl cmp::PartialOrd for RouteGraphNode {
 722         fn partial_cmp(&self, other: &RouteGraphNode) -> Option<cmp::Ordering> {
 723                 Some(self.cmp(other))
 724         }
 725 }
 726
 727 struct DummyDirectionalChannelInfo {
 728         src_node_id: PublicKey,
 729         cltv_expiry_delta: u32,
 730         htlc_minimum_msat: u64,
 731         fee_base_msat: u32,
 732         fee_proportional_millionths: u32,
 733 }
 734
 735 impl Router {
 736         /// Creates a new router with the given node_id to be used as the source for get_route()
 737         pub fn new(our_pubkey: PublicKey, chain_monitor: Arc<ChainWatchInterface>, logger: Arc<Logger>) -> Router {
 738                 let mut nodes = BTreeMap::new();
 739                 nodes.insert(our_pubkey.clone(), NodeInfo {
 740                         channels: Vec::new(),
 741                         lowest_inbound_channel_fee_base_msat: u32::max_value(),
 742                         lowest_inbound_channel_fee_proportional_millionths: u32::max_value(),
 743                         features: NodeFeatures::empty(),
 744                         last_update: 0,
 745                         rgb: [0; 3],
 746                         alias: [0; 32],
 747                         addresses: Vec::new(),
 748                         announcement_message: None,
 749                 });
 750                 Router {
 751                         secp_ctx: Secp256k1::verification_only(),
 752                         network_map: RwLock::new(NetworkMap {
 753                                 channels: BTreeMap::new(),
 754                                 our_node_id: our_pubkey,
 755                                 nodes: nodes,
 756                         }),
 757                         chain_monitor,
 758                         logger,
 759                 }
 760         }
 761
 762         /// Dumps the entire network view of this Router to the logger provided in the constructor at
 763         /// level Trace
 764         pub fn trace_state(&self) {
 765                 log_trace!(self, "{}", self.network_map.read().unwrap());
 766         }
 767
 768         /// Get network addresses by node id
 769         pub fn get_addresses(&self, pubkey: &PublicKey) -> Option<Vec<NetAddress>> {
 770                 let network = self.network_map.read().unwrap();
 771                 network.nodes.get(pubkey).map(|n| n.addresses.clone())
 772         }
 773
 774         /// Marks a node as having failed a route. This will avoid re-using the node in routes for now,
 775         /// with an exponential decay in node "badness". Note that there is deliberately no
 776         /// mark_channel_bad as a node may simply lie and suggest that an upstream channel from it is
 777         /// what failed the route and not the node itself. Instead, setting the blamed_upstream_node
 778         /// boolean will reduce the penalty, returning the node to usability faster. If the node is
 779         /// behaving correctly, it will disable the failing channel and we will use it again next time.
 780         pub fn mark_node_bad(&self, _node_id: &PublicKey, _blamed_upstream_node: bool) {
 781                 unimplemented!();
 782         }
 783
 784         fn remove_channel_in_nodes(nodes: &mut BTreeMap<PublicKey, NodeInfo>, chan: &ChannelInfo, short_channel_id: u64) {
 785                 macro_rules! remove_from_node {
 786                         ($node_id: expr) => {
 787                                 if let BtreeEntry::Occupied(mut entry) = nodes.entry($node_id) {
 788                                         entry.get_mut().channels.retain(|chan_id| {
 789                                                 short_channel_id != *NetworkMap::get_short_id(chan_id)
 790                                         });
 791                                         if entry.get().channels.is_empty() {
 792                                                 entry.remove_entry();
 793                                         }
 794                                 } else {
 795                                         panic!("Had channel that pointed to unknown node (ie inconsistent network map)!");
 796                                 }
 797                         }
 798                 }
 799                 remove_from_node!(chan.one_to_two.src_node_id);
 800                 remove_from_node!(chan.two_to_one.src_node_id);
 801         }
 802
 803         /// Gets a route from us to the given target node.
 804         ///
 805         /// Extra routing hops between known nodes and the target will be used if they are included in
 806         /// last_hops.
 807         ///
 808         /// If some channels aren't announced, it may be useful to fill in a first_hops with the
 809         /// results from a local ChannelManager::list_usable_channels() call. If it is filled in, our
 810         /// (this Router's) view of our local channels will be ignored, and only those in first_hops
 811         /// will be used.
 812         ///
 813         /// Panics if first_hops contains channels without short_channel_ids
 814         /// (ChannelManager::list_usable_channels will never include such channels).
 815         ///
 816         /// The fees on channels from us to next-hops are ignored (as they are assumed to all be
 817         /// equal), however the enabled/disabled bit on such channels as well as the htlc_minimum_msat
 818         /// *is* checked as they may change based on the receiving node.
 819         pub fn get_route(&self, target: &PublicKey, first_hops: Option<&[channelmanager::ChannelDetails]>, last_hops: &[RouteHint], final_value_msat: u64, final_cltv: u32) -> Result<Route, LightningError> {
 820                 // TODO: Obviously *only* using total fee cost sucks. We should consider weighting by
 821                 // uptime/success in using a node in the past.
 822                 let network = self.network_map.read().unwrap();
 823
 824                 if *target == network.our_node_id {
 825                         return Err(LightningError{err: "Cannot generate a route to ourselves", action: ErrorAction::IgnoreError});
 826                 }
 827
 828                 if final_value_msat > 21_000_000 * 1_0000_0000 * 1000 {
 829                         return Err(LightningError{err: "Cannot generate a route of more value than all existing satoshis", action: ErrorAction::IgnoreError});
 830                 }
 831
 832                 // We do a dest-to-source Dijkstra's sorting by each node's distance from the destination
 833                 // plus the minimum per-HTLC fee to get from it to another node (aka "shitty A*").
 834                 // TODO: There are a few tweaks we could do, including possibly pre-calculating more stuff
 835                 // to use as the A* heuristic beyond just the cost to get one node further than the current
 836                 // one.
 837
 838                 let dummy_directional_info = DummyDirectionalChannelInfo { // used for first_hops routes
 839                         src_node_id: network.our_node_id.clone(),
 840                         cltv_expiry_delta: 0,
 841                         htlc_minimum_msat: 0,
 842                         fee_base_msat: 0,
 843                         fee_proportional_millionths: 0,
 844                 };
 845
 846                 let mut targets = BinaryHeap::new(); //TODO: Do we care about switching to eg Fibbonaci heap?
 847                 let mut dist = HashMap::with_capacity(network.nodes.len());
 848
 849                 let mut first_hop_targets = HashMap::with_capacity(if first_hops.is_some() { first_hops.as_ref().unwrap().len() } else { 0 });
 850                 if let Some(hops) = first_hops {
 851                         for chan in hops {
 852                                 let short_channel_id = chan.short_channel_id.expect("first_hops should be filled in with usable channels, not pending ones");
 853                                 if chan.remote_network_id == *target {
 854                                         return Ok(Route {
 855                                                 hops: vec![RouteHop {
 856                                                         pubkey: chan.remote_network_id,
 857                                                         short_channel_id,
 858                                                         fee_msat: final_value_msat,
 859                                                         cltv_expiry_delta: final_cltv,
 860                                                 }],
 861                                         });
 862                                 }
 863                                 first_hop_targets.insert(chan.remote_network_id, short_channel_id);
 864                         }
 865                         if first_hop_targets.is_empty() {
 866                                 return Err(LightningError{err: "Cannot route when there are no outbound routes away from us", action: ErrorAction::IgnoreError});
 867                         }
 868                 }
 869
 870                 macro_rules! add_entry {
 871                         // Adds entry which goes from the node pointed to by $directional_info to
 872                         // $dest_node_id over the channel with id $chan_id with fees described in
 873                         // $directional_info.
 874                         ( $chan_id: expr, $dest_node_id: expr, $directional_info: expr, $starting_fee_msat: expr ) => {
 875                                 //TODO: Explore simply adding fee to hit htlc_minimum_msat
 876                                 if $starting_fee_msat as u64 + final_value_msat >= $directional_info.htlc_minimum_msat {
 877                                         let proportional_fee_millions = ($starting_fee_msat + final_value_msat).checked_mul($directional_info.fee_proportional_millionths as u64);
 878                                         if let Some(new_fee) = proportional_fee_millions.and_then(|part| {
 879                                                         ($directional_info.fee_base_msat as u64).checked_add(part / 1000000) })
 880                                         {
 881                                                 let mut total_fee = $starting_fee_msat as u64;
 882                                                 let hm_entry = dist.entry(&$directional_info.src_node_id);
 883                                                 let old_entry = hm_entry.or_insert_with(|| {
 884                                                         let node = network.nodes.get(&$directional_info.src_node_id).unwrap();
 885                                                         (u64::max_value(),
 886                                                                 node.lowest_inbound_channel_fee_base_msat,
 887                                                                 node.lowest_inbound_channel_fee_proportional_millionths,
 888                                                                 RouteHop {
 889                                                                         pubkey: $dest_node_id.clone(),
 890                                                                         short_channel_id: 0,
 891                                                                         fee_msat: 0,
 892                                                                         cltv_expiry_delta: 0,
 893                                                         })
 894                                                 });
 895                                                 if $directional_info.src_node_id != network.our_node_id {
 896                                                         // Ignore new_fee for channel-from-us as we assume all channels-from-us
 897                                                         // will have the same effective-fee
 898                                                         total_fee += new_fee;
 899                                                         if let Some(fee_inc) = final_value_msat.checked_add(total_fee).and_then(|inc| { (old_entry.2 as u64).checked_mul(inc) }) {
 900                                                                 total_fee += fee_inc / 1000000 + (old_entry.1 as u64);
 901                                                         } else {
 902                                                                 // max_value means we'll always fail the old_entry.0 > total_fee check
 903                                                                 total_fee = u64::max_value();
 904                                                         }
 905                                                 }
 906                                                 let new_graph_node = RouteGraphNode {
 907                                                         pubkey: $directional_info.src_node_id,
 908                                                         lowest_fee_to_peer_through_node: total_fee,
 909                                                         lowest_fee_to_node: $starting_fee_msat as u64 + new_fee,
 910                                                 };
 911                                                 if old_entry.0 > total_fee {
 912                                                         targets.push(new_graph_node);
 913                                                         old_entry.0 = total_fee;
 914                                                         old_entry.3 = RouteHop {
 915                                                                 pubkey: $dest_node_id.clone(),
 916                                                                 short_channel_id: $chan_id.clone(),
 917                                                                 fee_msat: new_fee, // This field is ignored on the last-hop anyway
 918                                                                 cltv_expiry_delta: $directional_info.cltv_expiry_delta as u32,
 919                                                         }
 920                                                 }
 921                                         }
 922                                 }
 923                         };
 924                 }
 925
 926                 macro_rules! add_entries_to_cheapest_to_target_node {
 927                         ( $node: expr, $node_id: expr, $fee_to_target_msat: expr ) => {
 928                                 if first_hops.is_some() {
 929                                         if let Some(first_hop) = first_hop_targets.get(&$node_id) {
 930                                                 add_entry!(first_hop, $node_id, dummy_directional_info, $fee_to_target_msat);
 931                                         }
 932                                 }
 933
 934                                 if !$node.features.requires_unknown_bits() {
 935                                         for chan_id in $node.channels.iter() {
 936                                                 let chan = network.channels.get(chan_id).unwrap();
 937                                                 if !chan.features.requires_unknown_bits() {
 938                                                         if chan.one_to_two.src_node_id == *$node_id {
 939                                                                 // ie $node is one, ie next hop in A* is two, via the two_to_one channel
 940                                                                 if first_hops.is_none() || chan.two_to_one.src_node_id != network.our_node_id {
 941                                                                         if chan.two_to_one.enabled {
 942                                                                                 add_entry!(chan_id, chan.one_to_two.src_node_id, chan.two_to_one, $fee_to_target_msat);
 943                                                                         }
 944                                                                 }
 945                                                         } else {
 946                                                                 if first_hops.is_none() || chan.one_to_two.src_node_id != network.our_node_id {
 947                                                                         if chan.one_to_two.enabled {
 948                                                                                 add_entry!(chan_id, chan.two_to_one.src_node_id, chan.one_to_two, $fee_to_target_msat);
 949                                                                         }
 950                                                                 }
 951                                                         }
 952                                                 }
 953                                         }
 954                                 }
 955                         };
 956                 }
 957
 958                 match network.nodes.get(target) {
 959                         None => {},
 960                         Some(node) => {
 961                                 add_entries_to_cheapest_to_target_node!(node, target, 0);
 962                         },
 963                 }
 964
 965                 for hop in last_hops.iter() {
 966                         if first_hops.is_none() || hop.src_node_id != network.our_node_id { // first_hop overrules last_hops
 967                                 if network.nodes.get(&hop.src_node_id).is_some() {
 968                                         if first_hops.is_some() {
 969                                                 if let Some(first_hop) = first_hop_targets.get(&hop.src_node_id) {
 970                                                         add_entry!(first_hop, hop.src_node_id, dummy_directional_info, 0);
 971                                                 }
 972                                         }
 973                                         add_entry!(hop.short_channel_id, target, hop, 0);
 974                                 }
 975                         }
 976                 }
 977
 978                 while let Some(RouteGraphNode { pubkey, lowest_fee_to_node, .. }) = targets.pop() {
 979                         if pubkey == network.our_node_id {
 980                                 let mut res = vec!(dist.remove(&network.our_node_id).unwrap().3);
 981                                 while res.last().unwrap().pubkey != *target {
 982                                         let new_entry = match dist.remove(&res.last().unwrap().pubkey) {
 983                                                 Some(hop) => hop.3,
 984                                                 None => return Err(LightningError{err: "Failed to find a non-fee-overflowing path to the given destination", action: ErrorAction::IgnoreError}),
 985                                         };
 986                                         res.last_mut().unwrap().fee_msat = new_entry.fee_msat;
 987                                         res.last_mut().unwrap().cltv_expiry_delta = new_entry.cltv_expiry_delta;
 988                                         res.push(new_entry);
 989                                 }
 990                                 res.last_mut().unwrap().fee_msat = final_value_msat;
 991                                 res.last_mut().unwrap().cltv_expiry_delta = final_cltv;
 992                                 let route = Route { hops: res };
 993                                 log_trace!(self, "Got route: {}", log_route!(route));
 994                                 return Ok(route);
 995                         }
 996
 997                         match network.nodes.get(&pubkey) {
 998                                 None => {},
 999                                 Some(node) => {
1000                                         add_entries_to_cheapest_to_target_node!(node, &pubkey, lowest_fee_to_node);
1001                                 },
1002                         }
1003                 }
1004
1005                 Err(LightningError{err: "Failed to find a path to the given destination", action: ErrorAction::IgnoreError})
1006         }
1007 }
1008
1009 #[cfg(test)]
1010 mod tests {
1011         use chain::chaininterface;
1012         use ln::channelmanager;
1013         use ln::router::{Router,NodeInfo,NetworkMap,ChannelInfo,DirectionalChannelInfo,RouteHint};
1014         use ln::msgs::{ChannelFeatures, NodeFeatures, LightningError, ErrorAction};
1015         use util::test_utils;
1016         use util::test_utils::TestVecWriter;
1017         use util::logger::Logger;
1018         use util::ser::{Writeable, Readable};
1019
1020         use bitcoin_hashes::sha256d::Hash as Sha256dHash;
1021         use bitcoin_hashes::Hash;
1022         use bitcoin::network::constants::Network;
1023
1024         use hex;
1025
1026         use secp256k1::key::{PublicKey,SecretKey};
1027         use secp256k1::Secp256k1;
1028
1029         use std::sync::Arc;
1030
1031         #[test]
1032         fn route_test() {
1033                 let secp_ctx = Secp256k1::new();
1034                 let our_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap());
1035                 let logger: Arc<Logger> = Arc::new(test_utils::TestLogger::new());
1036                 let chain_monitor = Arc::new(chaininterface::ChainWatchInterfaceUtil::new(Network::Testnet, Arc::clone(&logger)));
1037                 let router = Router::new(our_id, chain_monitor, Arc::clone(&logger));
1038
1039                 // Build network from our_id to node8:
1040                 //
1041                 //        -1(1)2-  node1  -1(3)2-
1042                 //       /                       \
1043                 // our_id -1(12)2- node8 -1(13)2--- node3
1044                 //       \                       /
1045                 //        -1(2)2-  node2  -1(4)2-
1046                 //
1047                 //
1048                 // chan1  1-to-2: disabled
1049                 // chan1  2-to-1: enabled, 0 fee
1050                 //
1051                 // chan2  1-to-2: enabled, ignored fee
1052                 // chan2  2-to-1: enabled, 0 fee
1053                 //
1054                 // chan3  1-to-2: enabled, 0 fee
1055                 // chan3  2-to-1: enabled, 100 msat fee
1056                 //
1057                 // chan4  1-to-2: enabled, 100% fee
1058                 // chan4  2-to-1: enabled, 0 fee
1059                 //
1060                 // chan12 1-to-2: enabled, ignored fee
1061                 // chan12 2-to-1: enabled, 0 fee
1062                 //
1063                 // chan13 1-to-2: enabled, 200% fee
1064                 // chan13 2-to-1: enabled, 0 fee
1065                 //
1066                 //
1067                 //       -1(5)2- node4 -1(8)2--
1068                 //       |         2          |
1069                 //       |       (11)         |
1070                 //      /          1           \
1071                 // node3--1(6)2- node5 -1(9)2--- node7 (not in global route map)
1072                 //      \                      /
1073                 //       -1(7)2- node6 -1(10)2-
1074                 //
1075                 // chan5  1-to-2: enabled, 100 msat fee
1076                 // chan5  2-to-1: enabled, 0 fee
1077                 //
1078                 // chan6  1-to-2: enabled, 0 fee
1079                 // chan6  2-to-1: enabled, 0 fee
1080                 //
1081                 // chan7  1-to-2: enabled, 100% fee
1082                 // chan7  2-to-1: enabled, 0 fee
1083                 //
1084                 // chan8  1-to-2: enabled, variable fee (0 then 1000 msat)
1085                 // chan8  2-to-1: enabled, 0 fee
1086                 //
1087                 // chan9  1-to-2: enabled, 1001 msat fee
1088                 // chan9  2-to-1: enabled, 0 fee
1089                 //
1090                 // chan10 1-to-2: enabled, 0 fee
1091                 // chan10 2-to-1: enabled, 0 fee
1092                 //
1093                 // chan11 1-to-2: enabled, 0 fee
1094                 // chan11 2-to-1: enabled, 0 fee
1095
1096                 let node1 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0202020202020202020202020202020202020202020202020202020202020202").unwrap()[..]).unwrap());
1097                 let node2 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0303030303030303030303030303030303030303030303030303030303030303").unwrap()[..]).unwrap());
1098                 let node3 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0404040404040404040404040404040404040404040404040404040404040404").unwrap()[..]).unwrap());
1099                 let node4 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0505050505050505050505050505050505050505050505050505050505050505").unwrap()[..]).unwrap());
1100                 let node5 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0606060606060606060606060606060606060606060606060606060606060606").unwrap()[..]).unwrap());
1101                 let node6 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0707070707070707070707070707070707070707070707070707070707070707").unwrap()[..]).unwrap());
1102                 let node7 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0808080808080808080808080808080808080808080808080808080808080808").unwrap()[..]).unwrap());
1103                 let node8 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0909090909090909090909090909090909090909090909090909090909090909").unwrap()[..]).unwrap());
1104
1105                 let zero_hash = Sha256dHash::hash(&[0; 32]);
1106
1107                 {
1108                         let mut network = router.network_map.write().unwrap();
1109
1110                         network.nodes.insert(node1.clone(), NodeInfo {
1111                                 channels: vec!(NetworkMap::get_key(1, zero_hash.clone()), NetworkMap::get_key(3, zero_hash.clone())),
1112                                 lowest_inbound_channel_fee_base_msat: 100,
1113                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1114                                 features: NodeFeatures::empty(),
1115                                 last_update: 1,
1116                                 rgb: [0; 3],
1117                                 alias: [0; 32],
1118                                 addresses: Vec::new(),
1119                                 announcement_message: None,
1120                         });
1121                         network.channels.insert(NetworkMap::get_key(1, zero_hash.clone()), ChannelInfo {
1122                                 features: ChannelFeatures::empty(),
1123                                 one_to_two: DirectionalChannelInfo {
1124                                         src_node_id: our_id.clone(),
1125                                         last_update: 0,
1126                                         enabled: false,
1127                                         cltv_expiry_delta: u16::max_value(), // This value should be ignored
1128                                         htlc_minimum_msat: 0,
1129                                         fee_base_msat: u32::max_value(), // This value should be ignored
1130                                         fee_proportional_millionths: u32::max_value(), // This value should be ignored
1131                                         last_update_message: None,
1132                                 }, two_to_one: DirectionalChannelInfo {
1133                                         src_node_id: node1.clone(),
1134                                         last_update: 0,
1135                                         enabled: true,
1136                                         cltv_expiry_delta: 0,
1137                                         htlc_minimum_msat: 0,
1138                                         fee_base_msat: 0,
1139                                         fee_proportional_millionths: 0,
1140                                         last_update_message: None,
1141                                 },
1142                                 announcement_message: None,
1143                         });
1144                         network.nodes.insert(node2.clone(), NodeInfo {
1145                                 channels: vec!(NetworkMap::get_key(2, zero_hash.clone()), NetworkMap::get_key(4, zero_hash.clone())),
1146                                 lowest_inbound_channel_fee_base_msat: 0,
1147                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1148                                 features: NodeFeatures::empty(),
1149                                 last_update: 1,
1150                                 rgb: [0; 3],
1151                                 alias: [0; 32],
1152                                 addresses: Vec::new(),
1153                                 announcement_message: None,
1154                         });
1155                         network.channels.insert(NetworkMap::get_key(2, zero_hash.clone()), ChannelInfo {
1156                                 features: ChannelFeatures::empty(),
1157                                 one_to_two: DirectionalChannelInfo {
1158                                         src_node_id: our_id.clone(),
1159                                         last_update: 0,
1160                                         enabled: true,
1161                                         cltv_expiry_delta: u16::max_value(), // This value should be ignored
1162                                         htlc_minimum_msat: 0,
1163                                         fee_base_msat: u32::max_value(), // This value should be ignored
1164                                         fee_proportional_millionths: u32::max_value(), // This value should be ignored
1165                                         last_update_message: None,
1166                                 }, two_to_one: DirectionalChannelInfo {
1167                                         src_node_id: node2.clone(),
1168                                         last_update: 0,
1169                                         enabled: true,
1170                                         cltv_expiry_delta: 0,
1171                                         htlc_minimum_msat: 0,
1172                                         fee_base_msat: 0,
1173                                         fee_proportional_millionths: 0,
1174                                         last_update_message: None,
1175                                 },
1176                                 announcement_message: None,
1177                         });
1178                         network.nodes.insert(node8.clone(), NodeInfo {
1179                                 channels: vec!(NetworkMap::get_key(12, zero_hash.clone()), NetworkMap::get_key(13, zero_hash.clone())),
1180                                 lowest_inbound_channel_fee_base_msat: 0,
1181                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1182                                 features: NodeFeatures::empty(),
1183                                 last_update: 1,
1184                                 rgb: [0; 3],
1185                                 alias: [0; 32],
1186                                 addresses: Vec::new(),
1187                                 announcement_message: None,
1188                         });
1189                         network.channels.insert(NetworkMap::get_key(12, zero_hash.clone()), ChannelInfo {
1190                                 features: ChannelFeatures::empty(),
1191                                 one_to_two: DirectionalChannelInfo {
1192                                         src_node_id: our_id.clone(),
1193                                         last_update: 0,
1194                                         enabled: true,
1195                                         cltv_expiry_delta: u16::max_value(), // This value should be ignored
1196                                         htlc_minimum_msat: 0,
1197                                         fee_base_msat: u32::max_value(), // This value should be ignored
1198                                         fee_proportional_millionths: u32::max_value(), // This value should be ignored
1199                                         last_update_message: None,
1200                                 }, two_to_one: DirectionalChannelInfo {
1201                                         src_node_id: node8.clone(),
1202                                         last_update: 0,
1203                                         enabled: true,
1204                                         cltv_expiry_delta: 0,
1205                                         htlc_minimum_msat: 0,
1206                                         fee_base_msat: 0,
1207                                         fee_proportional_millionths: 0,
1208                                         last_update_message: None,
1209                                 },
1210                                 announcement_message: None,
1211                         });
1212                         network.nodes.insert(node3.clone(), NodeInfo {
1213                                 channels: vec!(
1214                                         NetworkMap::get_key(3, zero_hash.clone()),
1215                                         NetworkMap::get_key(4, zero_hash.clone()),
1216                                         NetworkMap::get_key(13, zero_hash.clone()),
1217                                         NetworkMap::get_key(5, zero_hash.clone()),
1218                                         NetworkMap::get_key(6, zero_hash.clone()),
1219                                         NetworkMap::get_key(7, zero_hash.clone())),
1220                                 lowest_inbound_channel_fee_base_msat: 0,
1221                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1222                                 features: NodeFeatures::empty(),
1223                                 last_update: 1,
1224                                 rgb: [0; 3],
1225                                 alias: [0; 32],
1226                                 addresses: Vec::new(),
1227                                 announcement_message: None,
1228                         });
1229                         network.channels.insert(NetworkMap::get_key(3, zero_hash.clone()), ChannelInfo {
1230                                 features: ChannelFeatures::empty(),
1231                                 one_to_two: DirectionalChannelInfo {
1232                                         src_node_id: node1.clone(),
1233                                         last_update: 0,
1234                                         enabled: true,
1235                                         cltv_expiry_delta: (3 << 8) | 1,
1236                                         htlc_minimum_msat: 0,
1237                                         fee_base_msat: 0,
1238                                         fee_proportional_millionths: 0,
1239                                         last_update_message: None,
1240                                 }, two_to_one: DirectionalChannelInfo {
1241                                         src_node_id: node3.clone(),
1242                                         last_update: 0,
1243                                         enabled: true,
1244                                         cltv_expiry_delta: (3 << 8) | 2,
1245                                         htlc_minimum_msat: 0,
1246                                         fee_base_msat: 100,
1247                                         fee_proportional_millionths: 0,
1248                                         last_update_message: None,
1249                                 },
1250                                 announcement_message: None,
1251                         });
1252                         network.channels.insert(NetworkMap::get_key(4, zero_hash.clone()), ChannelInfo {
1253                                 features: ChannelFeatures::empty(),
1254                                 one_to_two: DirectionalChannelInfo {
1255                                         src_node_id: node2.clone(),
1256                                         last_update: 0,
1257                                         enabled: true,
1258                                         cltv_expiry_delta: (4 << 8) | 1,
1259                                         htlc_minimum_msat: 0,
1260                                         fee_base_msat: 0,
1261                                         fee_proportional_millionths: 1000000,
1262                                         last_update_message: None,
1263                                 }, two_to_one: DirectionalChannelInfo {
1264                                         src_node_id: node3.clone(),
1265                                         last_update: 0,
1266                                         enabled: true,
1267                                         cltv_expiry_delta: (4 << 8) | 2,
1268                                         htlc_minimum_msat: 0,
1269                                         fee_base_msat: 0,
1270                                         fee_proportional_millionths: 0,
1271                                         last_update_message: None,
1272                                 },
1273                                 announcement_message: None,
1274                         });
1275                         network.channels.insert(NetworkMap::get_key(13, zero_hash.clone()), ChannelInfo {
1276                                 features: ChannelFeatures::empty(),
1277                                 one_to_two: DirectionalChannelInfo {
1278                                         src_node_id: node8.clone(),
1279                                         last_update: 0,
1280                                         enabled: true,
1281                                         cltv_expiry_delta: (13 << 8) | 1,
1282                                         htlc_minimum_msat: 0,
1283                                         fee_base_msat: 0,
1284                                         fee_proportional_millionths: 2000000,
1285                                         last_update_message: None,
1286                                 }, two_to_one: DirectionalChannelInfo {
1287                                         src_node_id: node3.clone(),
1288                                         last_update: 0,
1289                                         enabled: true,
1290                                         cltv_expiry_delta: (13 << 8) | 2,
1291                                         htlc_minimum_msat: 0,
1292                                         fee_base_msat: 0,
1293                                         fee_proportional_millionths: 0,
1294                                         last_update_message: None,
1295                                 },
1296                                 announcement_message: None,
1297                         });
1298                         network.nodes.insert(node4.clone(), NodeInfo {
1299                                 channels: vec!(NetworkMap::get_key(5, zero_hash.clone()), NetworkMap::get_key(11, zero_hash.clone())),
1300                                 lowest_inbound_channel_fee_base_msat: 0,
1301                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1302                                 features: NodeFeatures::empty(),
1303                                 last_update: 1,
1304                                 rgb: [0; 3],
1305                                 alias: [0; 32],
1306                                 addresses: Vec::new(),
1307                                 announcement_message: None,
1308                         });
1309                         network.channels.insert(NetworkMap::get_key(5, zero_hash.clone()), ChannelInfo {
1310                                 features: ChannelFeatures::empty(),
1311                                 one_to_two: DirectionalChannelInfo {
1312                                         src_node_id: node3.clone(),
1313                                         last_update: 0,
1314                                         enabled: true,
1315                                         cltv_expiry_delta: (5 << 8) | 1,
1316                                         htlc_minimum_msat: 0,
1317                                         fee_base_msat: 100,
1318                                         fee_proportional_millionths: 0,
1319                                         last_update_message: None,
1320                                 }, two_to_one: DirectionalChannelInfo {
1321                                         src_node_id: node4.clone(),
1322                                         last_update: 0,
1323                                         enabled: true,
1324                                         cltv_expiry_delta: (5 << 8) | 2,
1325                                         htlc_minimum_msat: 0,
1326                                         fee_base_msat: 0,
1327                                         fee_proportional_millionths: 0,
1328                                         last_update_message: None,
1329                                 },
1330                                 announcement_message: None,
1331                         });
1332                         network.nodes.insert(node5.clone(), NodeInfo {
1333                                 channels: vec!(NetworkMap::get_key(6, zero_hash.clone()), NetworkMap::get_key(11, zero_hash.clone())),
1334                                 lowest_inbound_channel_fee_base_msat: 0,
1335                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1336                                 features: NodeFeatures::empty(),
1337                                 last_update: 1,
1338                                 rgb: [0; 3],
1339                                 alias: [0; 32],
1340                                 addresses: Vec::new(),
1341                                 announcement_message: None,
1342                         });
1343                         network.channels.insert(NetworkMap::get_key(6, zero_hash.clone()), ChannelInfo {
1344                                 features: ChannelFeatures::empty(),
1345                                 one_to_two: DirectionalChannelInfo {
1346                                         src_node_id: node3.clone(),
1347                                         last_update: 0,
1348                                         enabled: true,
1349                                         cltv_expiry_delta: (6 << 8) | 1,
1350                                         htlc_minimum_msat: 0,
1351                                         fee_base_msat: 0,
1352                                         fee_proportional_millionths: 0,
1353                                         last_update_message: None,
1354                                 }, two_to_one: DirectionalChannelInfo {
1355                                         src_node_id: node5.clone(),
1356                                         last_update: 0,
1357                                         enabled: true,
1358                                         cltv_expiry_delta: (6 << 8) | 2,
1359                                         htlc_minimum_msat: 0,
1360                                         fee_base_msat: 0,
1361                                         fee_proportional_millionths: 0,
1362                                         last_update_message: None,
1363                                 },
1364                                 announcement_message: None,
1365                         });
1366                         network.channels.insert(NetworkMap::get_key(11, zero_hash.clone()), ChannelInfo {
1367                                 features: ChannelFeatures::empty(),
1368                                 one_to_two: DirectionalChannelInfo {
1369                                         src_node_id: node5.clone(),
1370                                         last_update: 0,
1371                                         enabled: true,
1372                                         cltv_expiry_delta: (11 << 8) | 1,
1373                                         htlc_minimum_msat: 0,
1374                                         fee_base_msat: 0,
1375                                         fee_proportional_millionths: 0,
1376                                         last_update_message: None,
1377                                 }, two_to_one: DirectionalChannelInfo {
1378                                         src_node_id: node4.clone(),
1379                                         last_update: 0,
1380                                         enabled: true,
1381                                         cltv_expiry_delta: (11 << 8) | 2,
1382                                         htlc_minimum_msat: 0,
1383                                         fee_base_msat: 0,
1384                                         fee_proportional_millionths: 0,
1385                                         last_update_message: None,
1386                                 },
1387                                 announcement_message: None,
1388                         });
1389                         network.nodes.insert(node6.clone(), NodeInfo {
1390                                 channels: vec!(NetworkMap::get_key(7, zero_hash.clone())),
1391                                 lowest_inbound_channel_fee_base_msat: 0,
1392                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1393                                 features: NodeFeatures::empty(),
1394                                 last_update: 1,
1395                                 rgb: [0; 3],
1396                                 alias: [0; 32],
1397                                 addresses: Vec::new(),
1398                                 announcement_message: None,
1399                         });
1400                         network.channels.insert(NetworkMap::get_key(7, zero_hash.clone()), ChannelInfo {
1401                                 features: ChannelFeatures::empty(),
1402                                 one_to_two: DirectionalChannelInfo {
1403                                         src_node_id: node3.clone(),
1404                                         last_update: 0,
1405                                         enabled: true,
1406                                         cltv_expiry_delta: (7 << 8) | 1,
1407                                         htlc_minimum_msat: 0,
1408                                         fee_base_msat: 0,
1409                                         fee_proportional_millionths: 1000000,
1410                                         last_update_message: None,
1411                                 }, two_to_one: DirectionalChannelInfo {
1412                                         src_node_id: node6.clone(),
1413                                         last_update: 0,
1414                                         enabled: true,
1415                                         cltv_expiry_delta: (7 << 8) | 2,
1416                                         htlc_minimum_msat: 0,
1417                                         fee_base_msat: 0,
1418                                         fee_proportional_millionths: 0,
1419                                         last_update_message: None,
1420                                 },
1421                                 announcement_message: None,
1422                         });
1423                 }
1424
1425                 { // Simple route to 3 via 2
1426                         let route = router.get_route(&node3, None, &Vec::new(), 100, 42).unwrap();
1427                         assert_eq!(route.hops.len(), 2);
1428
1429                         assert_eq!(route.hops[0].pubkey, node2);
1430                         assert_eq!(route.hops[0].short_channel_id, 2);
1431                         assert_eq!(route.hops[0].fee_msat, 100);
1432                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1433
1434                         assert_eq!(route.hops[1].pubkey, node3);
1435                         assert_eq!(route.hops[1].short_channel_id, 4);
1436                         assert_eq!(route.hops[1].fee_msat, 100);
1437                         assert_eq!(route.hops[1].cltv_expiry_delta, 42);
1438                 }
1439
1440                 { // Disable channels 4 and 12 by requiring unknown feature bits
1441                         let mut network = router.network_map.write().unwrap();
1442                         network.channels.get_mut(&NetworkMap::get_key(4, zero_hash.clone())).unwrap().features.set_require_unknown_bits();
1443                         network.channels.get_mut(&NetworkMap::get_key(12, zero_hash.clone())).unwrap().features.set_require_unknown_bits();
1444                 }
1445
1446                 { // If all the channels require some features we don't understand, route should fail
1447                         if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = router.get_route(&node3, None, &Vec::new(), 100, 42) {
1448                                 assert_eq!(err, "Failed to find a path to the given destination");
1449                         } else { panic!(); }
1450                 }
1451
1452                 { // If we specify a channel to node8, that overrides our local channel view and that gets used
1453                         let our_chans = vec![channelmanager::ChannelDetails {
1454                                 channel_id: [0; 32],
1455                                 short_channel_id: Some(42),
1456                                 remote_network_id: node8.clone(),
1457                                 channel_value_satoshis: 0,
1458                                 user_id: 0,
1459                                 outbound_capacity_msat: 0,
1460                                 inbound_capacity_msat: 0,
1461                                 is_live: true,
1462                         }];
1463                         let route = router.get_route(&node3, Some(&our_chans), &Vec::new(), 100, 42).unwrap();
1464                         assert_eq!(route.hops.len(), 2);
1465
1466                         assert_eq!(route.hops[0].pubkey, node8);
1467                         assert_eq!(route.hops[0].short_channel_id, 42);
1468                         assert_eq!(route.hops[0].fee_msat, 200);
1469                         assert_eq!(route.hops[0].cltv_expiry_delta, (13 << 8) | 1);
1470
1471                         assert_eq!(route.hops[1].pubkey, node3);
1472                         assert_eq!(route.hops[1].short_channel_id, 13);
1473                         assert_eq!(route.hops[1].fee_msat, 100);
1474                         assert_eq!(route.hops[1].cltv_expiry_delta, 42);
1475                 }
1476
1477                 { // Re-enable channels 4 and 12 by wiping the unknown feature bits
1478                         let mut network = router.network_map.write().unwrap();
1479                         network.channels.get_mut(&NetworkMap::get_key(4, zero_hash.clone())).unwrap().features.clear_require_unknown_bits();
1480                         network.channels.get_mut(&NetworkMap::get_key(12, zero_hash.clone())).unwrap().features.clear_require_unknown_bits();
1481                 }
1482
1483                 { // Disable nodes 1, 2, and 8 by requiring unknown feature bits
1484                         let mut network = router.network_map.write().unwrap();
1485                         network.nodes.get_mut(&node1).unwrap().features.set_require_unknown_bits();
1486                         network.nodes.get_mut(&node2).unwrap().features.set_require_unknown_bits();
1487                         network.nodes.get_mut(&node8).unwrap().features.set_require_unknown_bits();
1488                 }
1489
1490                 { // If all nodes require some features we don't understand, route should fail
1491                         if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = router.get_route(&node3, None, &Vec::new(), 100, 42) {
1492                                 assert_eq!(err, "Failed to find a path to the given destination");
1493                         } else { panic!(); }
1494                 }
1495
1496                 { // If we specify a channel to node8, that overrides our local channel view and that gets used
1497                         let our_chans = vec![channelmanager::ChannelDetails {
1498                                 channel_id: [0; 32],
1499                                 short_channel_id: Some(42),
1500                                 remote_network_id: node8.clone(),
1501                                 channel_value_satoshis: 0,
1502                                 user_id: 0,
1503                                 outbound_capacity_msat: 0,
1504                                 inbound_capacity_msat: 0,
1505                                 is_live: true,
1506                         }];
1507                         let route = router.get_route(&node3, Some(&our_chans), &Vec::new(), 100, 42).unwrap();
1508                         assert_eq!(route.hops.len(), 2);
1509
1510                         assert_eq!(route.hops[0].pubkey, node8);
1511                         assert_eq!(route.hops[0].short_channel_id, 42);
1512                         assert_eq!(route.hops[0].fee_msat, 200);
1513                         assert_eq!(route.hops[0].cltv_expiry_delta, (13 << 8) | 1);
1514
1515                         assert_eq!(route.hops[1].pubkey, node3);
1516                         assert_eq!(route.hops[1].short_channel_id, 13);
1517                         assert_eq!(route.hops[1].fee_msat, 100);
1518                         assert_eq!(route.hops[1].cltv_expiry_delta, 42);
1519                 }
1520
1521                 { // Re-enable nodes 1, 2, and 8
1522                         let mut network = router.network_map.write().unwrap();
1523                         network.nodes.get_mut(&node1).unwrap().features.clear_require_unknown_bits();
1524                         network.nodes.get_mut(&node2).unwrap().features.clear_require_unknown_bits();
1525                         network.nodes.get_mut(&node8).unwrap().features.clear_require_unknown_bits();
1526                 }
1527
1528                 // Note that we don't test disabling node 3 and failing to route to it, as we (somewhat
1529                 // naively) assume that the user checked the feature bits on the invoice, which override
1530                 // the node_announcement.
1531
1532                 { // Route to 1 via 2 and 3 because our channel to 1 is disabled
1533                         let route = router.get_route(&node1, None, &Vec::new(), 100, 42).unwrap();
1534                         assert_eq!(route.hops.len(), 3);
1535
1536                         assert_eq!(route.hops[0].pubkey, node2);
1537                         assert_eq!(route.hops[0].short_channel_id, 2);
1538                         assert_eq!(route.hops[0].fee_msat, 200);
1539                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1540
1541                         assert_eq!(route.hops[1].pubkey, node3);
1542                         assert_eq!(route.hops[1].short_channel_id, 4);
1543                         assert_eq!(route.hops[1].fee_msat, 100);
1544                         assert_eq!(route.hops[1].cltv_expiry_delta, (3 << 8) | 2);
1545
1546                         assert_eq!(route.hops[2].pubkey, node1);
1547                         assert_eq!(route.hops[2].short_channel_id, 3);
1548                         assert_eq!(route.hops[2].fee_msat, 100);
1549                         assert_eq!(route.hops[2].cltv_expiry_delta, 42);
1550                 }
1551
1552                 { // If we specify a channel to node8, that overrides our local channel view and that gets used
1553                         let our_chans = vec![channelmanager::ChannelDetails {
1554                                 channel_id: [0; 32],
1555                                 short_channel_id: Some(42),
1556                                 remote_network_id: node8.clone(),
1557                                 channel_value_satoshis: 0,
1558                                 user_id: 0,
1559                                 outbound_capacity_msat: 0,
1560                                 inbound_capacity_msat: 0,
1561                                 is_live: true,
1562                         }];
1563                         let route = router.get_route(&node3, Some(&our_chans), &Vec::new(), 100, 42).unwrap();
1564                         assert_eq!(route.hops.len(), 2);
1565
1566                         assert_eq!(route.hops[0].pubkey, node8);
1567                         assert_eq!(route.hops[0].short_channel_id, 42);
1568                         assert_eq!(route.hops[0].fee_msat, 200);
1569                         assert_eq!(route.hops[0].cltv_expiry_delta, (13 << 8) | 1);
1570
1571                         assert_eq!(route.hops[1].pubkey, node3);
1572                         assert_eq!(route.hops[1].short_channel_id, 13);
1573                         assert_eq!(route.hops[1].fee_msat, 100);
1574                         assert_eq!(route.hops[1].cltv_expiry_delta, 42);
1575                 }
1576
1577                 let mut last_hops = vec!(RouteHint {
1578                                 src_node_id: node4.clone(),
1579                                 short_channel_id: 8,
1580                                 fee_base_msat: 0,
1581                                 fee_proportional_millionths: 0,
1582                                 cltv_expiry_delta: (8 << 8) | 1,
1583                                 htlc_minimum_msat: 0,
1584                         }, RouteHint {
1585                                 src_node_id: node5.clone(),
1586                                 short_channel_id: 9,
1587                                 fee_base_msat: 1001,
1588                                 fee_proportional_millionths: 0,
1589                                 cltv_expiry_delta: (9 << 8) | 1,
1590                                 htlc_minimum_msat: 0,
1591                         }, RouteHint {
1592                                 src_node_id: node6.clone(),
1593                                 short_channel_id: 10,
1594                                 fee_base_msat: 0,
1595                                 fee_proportional_millionths: 0,
1596                                 cltv_expiry_delta: (10 << 8) | 1,
1597                                 htlc_minimum_msat: 0,
1598                         });
1599
1600                 { // Simple test across 2, 3, 5, and 4 via a last_hop channel
1601                         let route = router.get_route(&node7, None, &last_hops, 100, 42).unwrap();
1602                         assert_eq!(route.hops.len(), 5);
1603
1604                         assert_eq!(route.hops[0].pubkey, node2);
1605                         assert_eq!(route.hops[0].short_channel_id, 2);
1606                         assert_eq!(route.hops[0].fee_msat, 100);
1607                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1608
1609                         assert_eq!(route.hops[1].pubkey, node3);
1610                         assert_eq!(route.hops[1].short_channel_id, 4);
1611                         assert_eq!(route.hops[1].fee_msat, 0);
1612                         assert_eq!(route.hops[1].cltv_expiry_delta, (6 << 8) | 1);
1613
1614                         assert_eq!(route.hops[2].pubkey, node5);
1615                         assert_eq!(route.hops[2].short_channel_id, 6);
1616                         assert_eq!(route.hops[2].fee_msat, 0);
1617                         assert_eq!(route.hops[2].cltv_expiry_delta, (11 << 8) | 1);
1618
1619                         assert_eq!(route.hops[3].pubkey, node4);
1620                         assert_eq!(route.hops[3].short_channel_id, 11);
1621                         assert_eq!(route.hops[3].fee_msat, 0);
1622                         assert_eq!(route.hops[3].cltv_expiry_delta, (8 << 8) | 1);
1623
1624                         assert_eq!(route.hops[4].pubkey, node7);
1625                         assert_eq!(route.hops[4].short_channel_id, 8);
1626                         assert_eq!(route.hops[4].fee_msat, 100);
1627                         assert_eq!(route.hops[4].cltv_expiry_delta, 42);
1628                 }
1629
1630                 { // Simple test with outbound channel to 4 to test that last_hops and first_hops connect
1631                         let our_chans = vec![channelmanager::ChannelDetails {
1632                                 channel_id: [0; 32],
1633                                 short_channel_id: Some(42),
1634                                 remote_network_id: node4.clone(),
1635                                 channel_value_satoshis: 0,
1636                                 user_id: 0,
1637                                 outbound_capacity_msat: 0,
1638                                 inbound_capacity_msat: 0,
1639                                 is_live: true,
1640                         }];
1641                         let route = router.get_route(&node7, Some(&our_chans), &last_hops, 100, 42).unwrap();
1642                         assert_eq!(route.hops.len(), 2);
1643
1644                         assert_eq!(route.hops[0].pubkey, node4);
1645                         assert_eq!(route.hops[0].short_channel_id, 42);
1646                         assert_eq!(route.hops[0].fee_msat, 0);
1647                         assert_eq!(route.hops[0].cltv_expiry_delta, (8 << 8) | 1);
1648
1649                         assert_eq!(route.hops[1].pubkey, node7);
1650                         assert_eq!(route.hops[1].short_channel_id, 8);
1651                         assert_eq!(route.hops[1].fee_msat, 100);
1652                         assert_eq!(route.hops[1].cltv_expiry_delta, 42);
1653                 }
1654
1655                 last_hops[0].fee_base_msat = 1000;
1656
1657                 { // Revert to via 6 as the fee on 8 goes up
1658                         let route = router.get_route(&node7, None, &last_hops, 100, 42).unwrap();
1659                         assert_eq!(route.hops.len(), 4);
1660
1661                         assert_eq!(route.hops[0].pubkey, node2);
1662                         assert_eq!(route.hops[0].short_channel_id, 2);
1663                         assert_eq!(route.hops[0].fee_msat, 200); // fee increased as its % of value transferred across node
1664                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1665
1666                         assert_eq!(route.hops[1].pubkey, node3);
1667                         assert_eq!(route.hops[1].short_channel_id, 4);
1668                         assert_eq!(route.hops[1].fee_msat, 100);
1669                         assert_eq!(route.hops[1].cltv_expiry_delta, (7 << 8) | 1);
1670
1671                         assert_eq!(route.hops[2].pubkey, node6);
1672                         assert_eq!(route.hops[2].short_channel_id, 7);
1673                         assert_eq!(route.hops[2].fee_msat, 0);
1674                         assert_eq!(route.hops[2].cltv_expiry_delta, (10 << 8) | 1);
1675
1676                         assert_eq!(route.hops[3].pubkey, node7);
1677                         assert_eq!(route.hops[3].short_channel_id, 10);
1678                         assert_eq!(route.hops[3].fee_msat, 100);
1679                         assert_eq!(route.hops[3].cltv_expiry_delta, 42);
1680                 }
1681
1682                 { // ...but still use 8 for larger payments as 6 has a variable feerate
1683                         let route = router.get_route(&node7, None, &last_hops, 2000, 42).unwrap();
1684                         assert_eq!(route.hops.len(), 5);
1685
1686                         assert_eq!(route.hops[0].pubkey, node2);
1687                         assert_eq!(route.hops[0].short_channel_id, 2);
1688                         assert_eq!(route.hops[0].fee_msat, 3000);
1689                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1690
1691                         assert_eq!(route.hops[1].pubkey, node3);
1692                         assert_eq!(route.hops[1].short_channel_id, 4);
1693                         assert_eq!(route.hops[1].fee_msat, 0);
1694                         assert_eq!(route.hops[1].cltv_expiry_delta, (6 << 8) | 1);
1695
1696                         assert_eq!(route.hops[2].pubkey, node5);
1697                         assert_eq!(route.hops[2].short_channel_id, 6);
1698                         assert_eq!(route.hops[2].fee_msat, 0);
1699                         assert_eq!(route.hops[2].cltv_expiry_delta, (11 << 8) | 1);
1700
1701                         assert_eq!(route.hops[3].pubkey, node4);
1702                         assert_eq!(route.hops[3].short_channel_id, 11);
1703                         assert_eq!(route.hops[3].fee_msat, 1000);
1704                         assert_eq!(route.hops[3].cltv_expiry_delta, (8 << 8) | 1);
1705
1706                         assert_eq!(route.hops[4].pubkey, node7);
1707                         assert_eq!(route.hops[4].short_channel_id, 8);
1708                         assert_eq!(route.hops[4].fee_msat, 2000);
1709                         assert_eq!(route.hops[4].cltv_expiry_delta, 42);
1710                 }
1711
1712                 { // Test Router serialization/deserialization
1713                         let mut w = TestVecWriter(Vec::new());
1714                         let network = router.network_map.read().unwrap();
1715                         assert!(!network.channels.is_empty());
1716                         assert!(!network.nodes.is_empty());
1717                         network.write(&mut w).unwrap();
1718                         assert!(<NetworkMap>::read(&mut ::std::io::Cursor::new(&w.0)).unwrap() == *network);
1719                 }
1720         }
1721 }