_ 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::features::{ChannelFeatures, NodeFeatures};
  18 use ln::msgs::{DecodeError,ErrorAction,LightningError,RoutingMessageHandler,NetAddress};
  19 use ln::msgs;
  20 use util::ser::{Writeable, Readable, Writer, ReadableArgs};
  21 use util::logger::Logger;
  22
  23 use std::cmp;
  24 use std::sync::{RwLock,Arc};
  25 use std::collections::{HashMap,BinaryHeap,BTreeMap};
  26 use std::collections::btree_map::Entry as BtreeEntry;
  27 use std;
  28
  29 /// A hop in a route
  30 #[derive(Clone, PartialEq)]
  31 pub struct RouteHop {
  32         /// The node_id of the node at this hop.
  33         pub pubkey: PublicKey,
  34         /// The node_announcement features of the node at this hop. For the last hop, these may be
  35         /// amended to match the features present in the invoice this node generated.
  36         pub node_features: NodeFeatures,
  37         /// The channel that should be used from the previous hop to reach this node.
  38         pub short_channel_id: u64,
  39         /// The channel_announcement features of the channel that should be used from the previous hop
  40         /// to reach this node.
  41         pub channel_features: ChannelFeatures,
  42         /// The fee taken on this hop. For the last hop, this should be the full value of the payment.
  43         pub fee_msat: u64,
  44         /// The CLTV delta added for this hop. For the last hop, this should be the full CLTV value
  45         /// expected at the destination, in excess of the current block height.
  46         pub cltv_expiry_delta: u32,
  47 }
  48
  49 /// A route from us through the network to a destination
  50 #[derive(Clone, PartialEq)]
  51 pub struct Route {
  52         /// The list of hops, NOT INCLUDING our own, where the last hop is the destination. Thus, this
  53         /// must always be at least length one. By protocol rules, this may not currently exceed 20 in
  54         /// length.
  55         pub hops: Vec<RouteHop>,
  56 }
  57
  58 impl Writeable for Route {
  59         fn write<W: ::util::ser::Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
  60                 (self.hops.len() as u8).write(writer)?;
  61                 for hop in self.hops.iter() {
  62                         hop.pubkey.write(writer)?;
  63                         hop.node_features.write(writer)?;
  64                         hop.short_channel_id.write(writer)?;
  65                         hop.channel_features.write(writer)?;
  66                         hop.fee_msat.write(writer)?;
  67                         hop.cltv_expiry_delta.write(writer)?;
  68                 }
  69                 Ok(())
  70         }
  71 }
  72
  73 impl<R: ::std::io::Read> Readable<R> for Route {
  74         fn read(reader: &mut R) -> Result<Route, DecodeError> {
  75                 let hops_count: u8 = Readable::read(reader)?;
  76                 let mut hops = Vec::with_capacity(hops_count as usize);
  77                 for _ in 0..hops_count {
  78                         hops.push(RouteHop {
  79                                 pubkey: Readable::read(reader)?,
  80                                 node_features: Readable::read(reader)?,
  81                                 short_channel_id: Readable::read(reader)?,
  82                                 channel_features: Readable::read(reader)?,
  83                                 fee_msat: Readable::read(reader)?,
  84                                 cltv_expiry_delta: Readable::read(reader)?,
  85                         });
  86                 }
  87                 Ok(Route {
  88                         hops
  89                 })
  90         }
  91 }
  92
  93 #[derive(PartialEq)]
  94 struct DirectionalChannelInfo {
  95         src_node_id: PublicKey,
  96         last_update: u32,
  97         enabled: bool,
  98         cltv_expiry_delta: u16,
  99         htlc_minimum_msat: u64,
 100         fee_base_msat: u32,
 101         fee_proportional_millionths: u32,
 102         last_update_message: Option<msgs::ChannelUpdate>,
 103 }
 104
 105 impl std::fmt::Display for DirectionalChannelInfo {
 106         fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
 107                 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)?;
 108                 Ok(())
 109         }
 110 }
 111
 112 impl_writeable!(DirectionalChannelInfo, 0, {
 113         src_node_id,
 114         last_update,
 115         enabled,
 116         cltv_expiry_delta,
 117         htlc_minimum_msat,
 118         fee_base_msat,
 119         fee_proportional_millionths,
 120         last_update_message
 121 });
 122
 123 #[derive(PartialEq)]
 124 struct ChannelInfo {
 125         features: ChannelFeatures,
 126         one_to_two: DirectionalChannelInfo,
 127         two_to_one: DirectionalChannelInfo,
 128         //this is cached here so we can send out it later if required by route_init_sync
 129         //keep an eye on this to see if the extra memory is a problem
 130         announcement_message: Option<msgs::ChannelAnnouncement>,
 131 }
 132
 133 impl std::fmt::Display for ChannelInfo {
 134         fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
 135                 write!(f, "features: {}, one_to_two: {}, two_to_one: {}", log_bytes!(self.features.encode()), self.one_to_two, self.two_to_one)?;
 136                 Ok(())
 137         }
 138 }
 139
 140 impl_writeable!(ChannelInfo, 0, {
 141         features,
 142         one_to_two,
 143         two_to_one,
 144         announcement_message
 145 });
 146
 147 #[derive(PartialEq)]
 148 struct NodeInfo {
 149         #[cfg(feature = "non_bitcoin_chain_hash_routing")]
 150         channels: Vec<(u64, Sha256dHash)>,
 151         #[cfg(not(feature = "non_bitcoin_chain_hash_routing"))]
 152         channels: Vec<u64>,
 153
 154         lowest_inbound_channel_fee_base_msat: u32,
 155         lowest_inbound_channel_fee_proportional_millionths: u32,
 156
 157         features: NodeFeatures,
 158         last_update: Option<u32>,
 159         rgb: [u8; 3],
 160         alias: [u8; 32],
 161         addresses: Vec<NetAddress>,
 162         //this is cached here so we can send out it later if required by route_init_sync
 163         //keep an eye on this to see if the extra memory is a problem
 164         announcement_message: Option<msgs::NodeAnnouncement>,
 165 }
 166
 167 impl std::fmt::Display for NodeInfo {
 168         fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
 169                 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[..])?;
 170                 Ok(())
 171         }
 172 }
 173
 174 impl Writeable for NodeInfo {
 175         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 176                 (self.channels.len() as u64).write(writer)?;
 177                 for ref chan in self.channels.iter() {
 178                         chan.write(writer)?;
 179                 }
 180                 self.lowest_inbound_channel_fee_base_msat.write(writer)?;
 181                 self.lowest_inbound_channel_fee_proportional_millionths.write(writer)?;
 182                 self.features.write(writer)?;
 183                 self.last_update.write(writer)?;
 184                 self.rgb.write(writer)?;
 185                 self.alias.write(writer)?;
 186                 (self.addresses.len() as u64).write(writer)?;
 187                 for ref addr in &self.addresses {
 188                         addr.write(writer)?;
 189                 }
 190                 self.announcement_message.write(writer)?;
 191                 Ok(())
 192         }
 193 }
 194
 195 const MAX_ALLOC_SIZE: u64 = 64*1024;
 196
 197 impl<R: ::std::io::Read> Readable<R> for NodeInfo {
 198         fn read(reader: &mut R) -> Result<NodeInfo, DecodeError> {
 199                 let channels_count: u64 = Readable::read(reader)?;
 200                 let mut channels = Vec::with_capacity(cmp::min(channels_count, MAX_ALLOC_SIZE / 8) as usize);
 201                 for _ in 0..channels_count {
 202                         channels.push(Readable::read(reader)?);
 203                 }
 204                 let lowest_inbound_channel_fee_base_msat = Readable::read(reader)?;
 205                 let lowest_inbound_channel_fee_proportional_millionths = Readable::read(reader)?;
 206                 let features = Readable::read(reader)?;
 207                 let last_update = Readable::read(reader)?;
 208                 let rgb = Readable::read(reader)?;
 209                 let alias = Readable::read(reader)?;
 210                 let addresses_count: u64 = Readable::read(reader)?;
 211                 let mut addresses = Vec::with_capacity(cmp::min(addresses_count, MAX_ALLOC_SIZE / 40) as usize);
 212                 for _ in 0..addresses_count {
 213                         match Readable::read(reader) {
 214                                 Ok(Ok(addr)) => { addresses.push(addr); },
 215                                 Ok(Err(_)) => return Err(DecodeError::InvalidValue),
 216                                 Err(DecodeError::ShortRead) => return Err(DecodeError::BadLengthDescriptor),
 217                                 _ => unreachable!(),
 218                         }
 219                 }
 220                 let announcement_message = Readable::read(reader)?;
 221                 Ok(NodeInfo {
 222                         channels,
 223                         lowest_inbound_channel_fee_base_msat,
 224                         lowest_inbound_channel_fee_proportional_millionths,
 225                         features,
 226                         last_update,
 227                         rgb,
 228                         alias,
 229                         addresses,
 230                         announcement_message
 231                 })
 232         }
 233 }
 234
 235 #[derive(PartialEq)]
 236 struct NetworkMap {
 237         #[cfg(feature = "non_bitcoin_chain_hash_routing")]
 238         channels: BTreeMap<(u64, Sha256dHash), ChannelInfo>,
 239         #[cfg(not(feature = "non_bitcoin_chain_hash_routing"))]
 240         channels: BTreeMap<u64, ChannelInfo>,
 241
 242         our_node_id: PublicKey,
 243         nodes: BTreeMap<PublicKey, NodeInfo>,
 244 }
 245
 246 impl Writeable for NetworkMap {
 247         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 248                 (self.channels.len() as u64).write(writer)?;
 249                 for (ref chan_id, ref chan_info) in self.channels.iter() {
 250                         (*chan_id).write(writer)?;
 251                         chan_info.write(writer)?;
 252                 }
 253                 self.our_node_id.write(writer)?;
 254                 (self.nodes.len() as u64).write(writer)?;
 255                 for (ref node_id, ref node_info) in self.nodes.iter() {
 256                         node_id.write(writer)?;
 257                         node_info.write(writer)?;
 258                 }
 259                 Ok(())
 260         }
 261 }
 262
 263 impl<R: ::std::io::Read> Readable<R> for NetworkMap {
 264         fn read(reader: &mut R) -> Result<NetworkMap, DecodeError> {
 265                 let channels_count: u64 = Readable::read(reader)?;
 266                 let mut channels = BTreeMap::new();
 267                 for _ in 0..channels_count {
 268                         let chan_id: u64 = Readable::read(reader)?;
 269                         let chan_info = Readable::read(reader)?;
 270                         channels.insert(chan_id, chan_info);
 271                 }
 272                 let our_node_id = Readable::read(reader)?;
 273                 let nodes_count: u64 = Readable::read(reader)?;
 274                 let mut nodes = BTreeMap::new();
 275                 for _ in 0..nodes_count {
 276                         let node_id = Readable::read(reader)?;
 277                         let node_info = Readable::read(reader)?;
 278                         nodes.insert(node_id, node_info);
 279                 }
 280                 Ok(NetworkMap {
 281                         channels,
 282                         our_node_id,
 283                         nodes,
 284                 })
 285         }
 286 }
 287
 288 impl std::fmt::Display for NetworkMap {
 289         fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
 290                 write!(f, "Node id {} network map\n[Channels]\n", log_pubkey!(self.our_node_id))?;
 291                 for (key, val) in self.channels.iter() {
 292                         write!(f, " {}: {}\n", key, val)?;
 293                 }
 294                 write!(f, "[Nodes]\n")?;
 295                 for (key, val) in self.nodes.iter() {
 296                         write!(f, " {}: {}\n", log_pubkey!(key), val)?;
 297                 }
 298                 Ok(())
 299         }
 300 }
 301
 302 impl NetworkMap {
 303         #[cfg(feature = "non_bitcoin_chain_hash_routing")]
 304         #[inline]
 305         fn get_key(short_channel_id: u64, chain_hash: Sha256dHash) -> (u64, Sha256dHash) {
 306                 (short_channel_id, chain_hash)
 307         }
 308
 309         #[cfg(not(feature = "non_bitcoin_chain_hash_routing"))]
 310         #[inline]
 311         fn get_key(short_channel_id: u64, _: Sha256dHash) -> u64 {
 312                 short_channel_id
 313         }
 314
 315         #[cfg(feature = "non_bitcoin_chain_hash_routing")]
 316         #[inline]
 317         fn get_short_id(id: &(u64, Sha256dHash)) -> &u64 {
 318                 &id.0
 319         }
 320
 321         #[cfg(not(feature = "non_bitcoin_chain_hash_routing"))]
 322         #[inline]
 323         fn get_short_id(id: &u64) -> &u64 {
 324                 id
 325         }
 326 }
 327
 328 /// A channel descriptor which provides a last-hop route to get_route
 329 pub struct RouteHint {
 330         /// The node_id of the non-target end of the route
 331         pub src_node_id: PublicKey,
 332         /// The short_channel_id of this channel
 333         pub short_channel_id: u64,
 334         /// The static msat-denominated fee which must be paid to use this channel
 335         pub fee_base_msat: u32,
 336         /// The dynamic proportional fee which must be paid to use this channel, denominated in
 337         /// millionths of the value being forwarded to the next hop.
 338         pub fee_proportional_millionths: u32,
 339         /// The difference in CLTV values between this node and the next node.
 340         pub cltv_expiry_delta: u16,
 341         /// The minimum value, in msat, which must be relayed to the next hop.
 342         pub htlc_minimum_msat: u64,
 343 }
 344
 345 /// Tracks a view of the network, receiving updates from peers and generating Routes to
 346 /// payment destinations.
 347 pub struct Router {
 348         secp_ctx: Secp256k1<secp256k1::VerifyOnly>,
 349         network_map: RwLock<NetworkMap>,
 350         chain_monitor: Arc<ChainWatchInterface>,
 351         logger: Arc<Logger>,
 352 }
 353
 354 const SERIALIZATION_VERSION: u8 = 1;
 355 const MIN_SERIALIZATION_VERSION: u8 = 1;
 356
 357 impl Writeable for Router {
 358         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 359                 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
 360                 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
 361
 362                 let network = self.network_map.read().unwrap();
 363                 network.write(writer)?;
 364                 Ok(())
 365         }
 366 }
 367
 368 /// Arguments for the creation of a Router that are not deserialized.
 369 /// At a high-level, the process for deserializing a Router and resuming normal operation is:
 370 /// 1) Deserialize the Router by filling in this struct and calling <Router>::read(reaser, args).
 371 /// 2) Register the new Router with your ChainWatchInterface
 372 pub struct RouterReadArgs {
 373         /// The ChainWatchInterface for use in the Router in the future.
 374         ///
 375         /// No calls to the ChainWatchInterface will be made during deserialization.
 376         pub chain_monitor: Arc<ChainWatchInterface>,
 377         /// The Logger for use in the ChannelManager and which may be used to log information during
 378         /// deserialization.
 379         pub logger: Arc<Logger>,
 380 }
 381
 382 impl<R: ::std::io::Read> ReadableArgs<R, RouterReadArgs> for Router {
 383         fn read(reader: &mut R, args: RouterReadArgs) -> Result<Router, DecodeError> {
 384                 let _ver: u8 = Readable::read(reader)?;
 385                 let min_ver: u8 = Readable::read(reader)?;
 386                 if min_ver > SERIALIZATION_VERSION {
 387                         return Err(DecodeError::UnknownVersion);
 388                 }
 389                 let network_map = Readable::read(reader)?;
 390                 Ok(Router {
 391                         secp_ctx: Secp256k1::verification_only(),
 392                         network_map: RwLock::new(network_map),
 393                         chain_monitor: args.chain_monitor,
 394                         logger: args.logger,
 395                 })
 396         }
 397 }
 398
 399 macro_rules! secp_verify_sig {
 400         ( $secp_ctx: expr, $msg: expr, $sig: expr, $pubkey: expr ) => {
 401                 match $secp_ctx.verify($msg, $sig, $pubkey) {
 402                         Ok(_) => {},
 403                         Err(_) => return Err(LightningError{err: "Invalid signature from remote node", action: ErrorAction::IgnoreError}),
 404                 }
 405         };
 406 }
 407
 408 impl RoutingMessageHandler for Router {
 409         fn handle_node_announcement(&self, msg: &msgs::NodeAnnouncement) -> Result<bool, LightningError> {
 410                 let msg_hash = hash_to_message!(&Sha256dHash::hash(&msg.contents.encode()[..])[..]);
 411                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.signature, &msg.contents.node_id);
 412
 413                 let mut network = self.network_map.write().unwrap();
 414                 match network.nodes.get_mut(&msg.contents.node_id) {
 415                         None => Err(LightningError{err: "No existing channels for node_announcement", action: ErrorAction::IgnoreError}),
 416                         Some(node) => {
 417                                 match node.last_update {
 418                                         Some(last_update) => if last_update >= msg.contents.timestamp {
 419                                                 return Err(LightningError{err: "Update older than last processed update", action: ErrorAction::IgnoreError});
 420                                         },
 421                                         None => {},
 422                                 }
 423
 424                                 node.features = msg.contents.features.clone();
 425                                 node.last_update = Some(msg.contents.timestamp);
 426                                 node.rgb = msg.contents.rgb;
 427                                 node.alias = msg.contents.alias;
 428                                 node.addresses = msg.contents.addresses.clone();
 429
 430                                 let should_relay = msg.contents.excess_data.is_empty() && msg.contents.excess_address_data.is_empty();
 431                                 node.announcement_message = if should_relay { Some(msg.clone()) } else { None };
 432                                 Ok(should_relay)
 433                         }
 434                 }
 435         }
 436
 437         fn handle_channel_announcement(&self, msg: &msgs::ChannelAnnouncement) -> Result<bool, LightningError> {
 438                 if msg.contents.node_id_1 == msg.contents.node_id_2 || msg.contents.bitcoin_key_1 == msg.contents.bitcoin_key_2 {
 439                         return Err(LightningError{err: "Channel announcement node had a channel with itself", action: ErrorAction::IgnoreError});
 440                 }
 441
 442                 let msg_hash = hash_to_message!(&Sha256dHash::hash(&msg.contents.encode()[..])[..]);
 443                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.node_signature_1, &msg.contents.node_id_1);
 444                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.node_signature_2, &msg.contents.node_id_2);
 445                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.bitcoin_signature_1, &msg.contents.bitcoin_key_1);
 446                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.bitcoin_signature_2, &msg.contents.bitcoin_key_2);
 447
 448                 let checked_utxo = match self.chain_monitor.get_chain_utxo(msg.contents.chain_hash, msg.contents.short_channel_id) {
 449                         Ok((script_pubkey, _value)) => {
 450                                 let expected_script = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
 451                                                                     .push_slice(&msg.contents.bitcoin_key_1.serialize())
 452                                                                     .push_slice(&msg.contents.bitcoin_key_2.serialize())
 453                                                                     .push_opcode(opcodes::all::OP_PUSHNUM_2)
 454                                                                     .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
 455                                 if script_pubkey != expected_script {
 456                                         return Err(LightningError{err: "Channel announcement keys didn't match on-chain script", action: ErrorAction::IgnoreError});
 457                                 }
 458                                 //TODO: Check if value is worth storing, use it to inform routing, and compare it
 459                                 //to the new HTLC max field in channel_update
 460                                 true
 461                         },
 462                         Err(ChainError::NotSupported) => {
 463                                 // Tentatively accept, potentially exposing us to DoS attacks
 464                                 false
 465                         },
 466                         Err(ChainError::NotWatched) => {
 467                                 return Err(LightningError{err: "Channel announced on an unknown chain", action: ErrorAction::IgnoreError});
 468                         },
 469                         Err(ChainError::UnknownTx) => {
 470                                 return Err(LightningError{err: "Channel announced without corresponding UTXO entry", action: ErrorAction::IgnoreError});
 471                         },
 472                 };
 473
 474                 let mut network_lock = self.network_map.write().unwrap();
 475                 let network = &mut *network_lock;
 476
 477                 let should_relay = msg.contents.excess_data.is_empty();
 478
 479                 let chan_info = ChannelInfo {
 480                                 features: msg.contents.features.clone(),
 481                                 one_to_two: DirectionalChannelInfo {
 482                                         src_node_id: msg.contents.node_id_1.clone(),
 483                                         last_update: 0,
 484                                         enabled: false,
 485                                         cltv_expiry_delta: u16::max_value(),
 486                                         htlc_minimum_msat: u64::max_value(),
 487                                         fee_base_msat: u32::max_value(),
 488                                         fee_proportional_millionths: u32::max_value(),
 489                                         last_update_message: None,
 490                                 },
 491                                 two_to_one: DirectionalChannelInfo {
 492                                         src_node_id: msg.contents.node_id_2.clone(),
 493                                         last_update: 0,
 494                                         enabled: false,
 495                                         cltv_expiry_delta: u16::max_value(),
 496                                         htlc_minimum_msat: u64::max_value(),
 497                                         fee_base_msat: u32::max_value(),
 498                                         fee_proportional_millionths: u32::max_value(),
 499                                         last_update_message: None,
 500                                 },
 501                                 announcement_message: if should_relay { Some(msg.clone()) } else { None },
 502                         };
 503
 504                 match network.channels.entry(NetworkMap::get_key(msg.contents.short_channel_id, msg.contents.chain_hash)) {
 505                         BtreeEntry::Occupied(mut entry) => {
 506                                 //TODO: because asking the blockchain if short_channel_id is valid is only optional
 507                                 //in the blockchain API, we need to handle it smartly here, though it's unclear
 508                                 //exactly how...
 509                                 if checked_utxo {
 510                                         // Either our UTXO provider is busted, there was a reorg, or the UTXO provider
 511                                         // only sometimes returns results. In any case remove the previous entry. Note
 512                                         // that the spec expects us to "blacklist" the node_ids involved, but we can't
 513                                         // do that because
 514                                         // a) we don't *require* a UTXO provider that always returns results.
 515                                         // b) we don't track UTXOs of channels we know about and remove them if they
 516                                         //    get reorg'd out.
 517                                         // c) it's unclear how to do so without exposing ourselves to massive DoS risk.
 518                                         Self::remove_channel_in_nodes(&mut network.nodes, &entry.get(), msg.contents.short_channel_id);
 519                                         *entry.get_mut() = chan_info;
 520                                 } else {
 521                                         return Err(LightningError{err: "Already have knowledge of channel", action: ErrorAction::IgnoreError})
 522                                 }
 523                         },
 524                         BtreeEntry::Vacant(entry) => {
 525                                 entry.insert(chan_info);
 526                         }
 527                 };
 528
 529                 macro_rules! add_channel_to_node {
 530                         ( $node_id: expr ) => {
 531                                 match network.nodes.entry($node_id) {
 532                                         BtreeEntry::Occupied(node_entry) => {
 533                                                 node_entry.into_mut().channels.push(NetworkMap::get_key(msg.contents.short_channel_id, msg.contents.chain_hash));
 534                                         },
 535                                         BtreeEntry::Vacant(node_entry) => {
 536                                                 node_entry.insert(NodeInfo {
 537                                                         channels: vec!(NetworkMap::get_key(msg.contents.short_channel_id, msg.contents.chain_hash)),
 538                                                         lowest_inbound_channel_fee_base_msat: u32::max_value(),
 539                                                         lowest_inbound_channel_fee_proportional_millionths: u32::max_value(),
 540                                                         features: NodeFeatures::empty(),
 541                                                         last_update: None,
 542                                                         rgb: [0; 3],
 543                                                         alias: [0; 32],
 544                                                         addresses: Vec::new(),
 545                                                         announcement_message: None,
 546                                                 });
 547                                         }
 548                                 }
 549                         };
 550                 }
 551
 552                 add_channel_to_node!(msg.contents.node_id_1);
 553                 add_channel_to_node!(msg.contents.node_id_2);
 554
 555                 Ok(should_relay)
 556         }
 557
 558         fn handle_htlc_fail_channel_update(&self, update: &msgs::HTLCFailChannelUpdate) {
 559                 match update {
 560                         &msgs::HTLCFailChannelUpdate::ChannelUpdateMessage { ref msg } => {
 561                                 let _ = self.handle_channel_update(msg);
 562                         },
 563                         &msgs::HTLCFailChannelUpdate::ChannelClosed { ref short_channel_id, ref is_permanent } => {
 564                                 let mut network = self.network_map.write().unwrap();
 565                                 if *is_permanent {
 566                                         if let Some(chan) = network.channels.remove(short_channel_id) {
 567                                                 Self::remove_channel_in_nodes(&mut network.nodes, &chan, *short_channel_id);
 568                                         }
 569                                 } else {
 570                                         if let Some(chan) = network.channels.get_mut(short_channel_id) {
 571                                                 chan.one_to_two.enabled = false;
 572                                                 chan.two_to_one.enabled = false;
 573                                         }
 574                                 }
 575                         },
 576                         &msgs::HTLCFailChannelUpdate::NodeFailure { ref node_id, ref is_permanent } => {
 577                                 if *is_permanent {
 578                                         //TODO: Wholly remove the node
 579                                 } else {
 580                                         self.mark_node_bad(node_id, false);
 581                                 }
 582                         },
 583                 }
 584         }
 585
 586         fn handle_channel_update(&self, msg: &msgs::ChannelUpdate) -> Result<bool, LightningError> {
 587                 let mut network = self.network_map.write().unwrap();
 588                 let dest_node_id;
 589                 let chan_enabled = msg.contents.flags & (1 << 1) != (1 << 1);
 590                 let chan_was_enabled;
 591
 592                 match network.channels.get_mut(&NetworkMap::get_key(msg.contents.short_channel_id, msg.contents.chain_hash)) {
 593                         None => return Err(LightningError{err: "Couldn't find channel for update", action: ErrorAction::IgnoreError}),
 594                         Some(channel) => {
 595                                 macro_rules! maybe_update_channel_info {
 596                                         ( $target: expr) => {
 597                                                 if $target.last_update >= msg.contents.timestamp {
 598                                                         return Err(LightningError{err: "Update older than last processed update", action: ErrorAction::IgnoreError});
 599                                                 }
 600                                                 chan_was_enabled = $target.enabled;
 601                                                 $target.last_update = msg.contents.timestamp;
 602                                                 $target.enabled = chan_enabled;
 603                                                 $target.cltv_expiry_delta = msg.contents.cltv_expiry_delta;
 604                                                 $target.htlc_minimum_msat = msg.contents.htlc_minimum_msat;
 605                                                 $target.fee_base_msat = msg.contents.fee_base_msat;
 606                                                 $target.fee_proportional_millionths = msg.contents.fee_proportional_millionths;
 607                                                 $target.last_update_message = if msg.contents.excess_data.is_empty() {
 608                                                         Some(msg.clone())
 609                                                 } else {
 610                                                         None
 611                                                 };
 612                                         }
 613                                 }
 614                                 let msg_hash = hash_to_message!(&Sha256dHash::hash(&msg.contents.encode()[..])[..]);
 615                                 if msg.contents.flags & 1 == 1 {
 616                                         dest_node_id = channel.one_to_two.src_node_id.clone();
 617                                         secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.signature, &channel.two_to_one.src_node_id);
 618                                         maybe_update_channel_info!(channel.two_to_one);
 619                                 } else {
 620                                         dest_node_id = channel.two_to_one.src_node_id.clone();
 621                                         secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.signature, &channel.one_to_two.src_node_id);
 622                                         maybe_update_channel_info!(channel.one_to_two);
 623                                 }
 624                         }
 625                 }
 626
 627                 if chan_enabled {
 628                         let node = network.nodes.get_mut(&dest_node_id).unwrap();
 629                         node.lowest_inbound_channel_fee_base_msat = cmp::min(node.lowest_inbound_channel_fee_base_msat, msg.contents.fee_base_msat);
 630                         node.lowest_inbound_channel_fee_proportional_millionths = cmp::min(node.lowest_inbound_channel_fee_proportional_millionths, msg.contents.fee_proportional_millionths);
 631                 } else if chan_was_enabled {
 632                         let mut lowest_inbound_channel_fee_base_msat = u32::max_value();
 633                         let mut lowest_inbound_channel_fee_proportional_millionths = u32::max_value();
 634
 635                         {
 636                                 let node = network.nodes.get(&dest_node_id).unwrap();
 637
 638                                 for chan_id in node.channels.iter() {
 639                                         let chan = network.channels.get(chan_id).unwrap();
 640                                         if chan.one_to_two.src_node_id == dest_node_id {
 641                                                 lowest_inbound_channel_fee_base_msat = cmp::min(lowest_inbound_channel_fee_base_msat, chan.two_to_one.fee_base_msat);
 642                                                 lowest_inbound_channel_fee_proportional_millionths = cmp::min(lowest_inbound_channel_fee_proportional_millionths, chan.two_to_one.fee_proportional_millionths);
 643                                         } else {
 644                                                 lowest_inbound_channel_fee_base_msat = cmp::min(lowest_inbound_channel_fee_base_msat, chan.one_to_two.fee_base_msat);
 645                                                 lowest_inbound_channel_fee_proportional_millionths = cmp::min(lowest_inbound_channel_fee_proportional_millionths, chan.one_to_two.fee_proportional_millionths);
 646                                         }
 647                                 }
 648                         }
 649
 650                         //TODO: satisfy the borrow-checker without a double-map-lookup :(
 651                         let mut_node = network.nodes.get_mut(&dest_node_id).unwrap();
 652                         mut_node.lowest_inbound_channel_fee_base_msat = lowest_inbound_channel_fee_base_msat;
 653                         mut_node.lowest_inbound_channel_fee_proportional_millionths = lowest_inbound_channel_fee_proportional_millionths;
 654                 }
 655
 656                 Ok(msg.contents.excess_data.is_empty())
 657         }
 658
 659
 660         fn get_next_channel_announcements(&self, starting_point: u64, batch_amount: u8) -> Vec<(msgs::ChannelAnnouncement, msgs::ChannelUpdate,msgs::ChannelUpdate)> {
 661                 let mut result = Vec::with_capacity(batch_amount as usize);
 662                 let network = self.network_map.read().unwrap();
 663                 let mut iter = network.channels.range(starting_point..);
 664                 while result.len() < batch_amount as usize {
 665                         if let Some((_, ref chan)) = iter.next() {
 666                                 if chan.announcement_message.is_some() &&
 667                                                 chan.one_to_two.last_update_message.is_some() &&
 668                                                 chan.two_to_one.last_update_message.is_some() {
 669                                         result.push((chan.announcement_message.clone().unwrap(),
 670                                                 chan.one_to_two.last_update_message.clone().unwrap(),
 671                                                 chan.two_to_one.last_update_message.clone().unwrap()));
 672                                 } else {
 673                                         // TODO: We may end up sending un-announced channel_updates if we are sending
 674                                         // initial sync data while receiving announce/updates for this channel.
 675                                 }
 676                         } else {
 677                                 return result;
 678                         }
 679                 }
 680                 result
 681         }
 682
 683         fn get_next_node_announcements(&self, starting_point: Option<&PublicKey>, batch_amount: u8) -> Vec<msgs::NodeAnnouncement> {
 684                 let mut result = Vec::with_capacity(batch_amount as usize);
 685                 let network = self.network_map.read().unwrap();
 686                 let mut iter = if let Some(pubkey) = starting_point {
 687                                 let mut iter = network.nodes.range((*pubkey)..);
 688                                 iter.next();
 689                                 iter
 690                         } else {
 691                                 network.nodes.range(..)
 692                         };
 693                 while result.len() < batch_amount as usize {
 694                         if let Some((_, ref node)) = iter.next() {
 695                                 if node.announcement_message.is_some() {
 696                                         result.push(node.announcement_message.clone().unwrap());
 697                                 }
 698                         } else {
 699                                 return result;
 700                         }
 701                 }
 702                 result
 703         }
 704 }
 705
 706 #[derive(Eq, PartialEq)]
 707 struct RouteGraphNode {
 708         pubkey: PublicKey,
 709         lowest_fee_to_peer_through_node: u64,
 710         lowest_fee_to_node: u64,
 711 }
 712
 713 impl cmp::Ord for RouteGraphNode {
 714         fn cmp(&self, other: &RouteGraphNode) -> cmp::Ordering {
 715                 other.lowest_fee_to_peer_through_node.cmp(&self.lowest_fee_to_peer_through_node)
 716                         .then_with(|| other.pubkey.serialize().cmp(&self.pubkey.serialize()))
 717         }
 718 }
 719
 720 impl cmp::PartialOrd for RouteGraphNode {
 721         fn partial_cmp(&self, other: &RouteGraphNode) -> Option<cmp::Ordering> {
 722                 Some(self.cmp(other))
 723         }
 724 }
 725
 726 struct DummyDirectionalChannelInfo {
 727         src_node_id: PublicKey,
 728         cltv_expiry_delta: u32,
 729         htlc_minimum_msat: u64,
 730         fee_base_msat: u32,
 731         fee_proportional_millionths: u32,
 732 }
 733
 734 impl Router {
 735         /// Creates a new router with the given node_id to be used as the source for get_route()
 736         pub fn new(our_pubkey: PublicKey, chain_monitor: Arc<ChainWatchInterface>, logger: Arc<Logger>) -> Router {
 737                 let mut nodes = BTreeMap::new();
 738                 nodes.insert(our_pubkey.clone(), NodeInfo {
 739                         channels: Vec::new(),
 740                         lowest_inbound_channel_fee_base_msat: u32::max_value(),
 741                         lowest_inbound_channel_fee_proportional_millionths: u32::max_value(),
 742                         features: NodeFeatures::empty(),
 743                         last_update: None,
 744                         rgb: [0; 3],
 745                         alias: [0; 32],
 746                         addresses: Vec::new(),
 747                         announcement_message: None,
 748                 });
 749                 Router {
 750                         secp_ctx: Secp256k1::verification_only(),
 751                         network_map: RwLock::new(NetworkMap {
 752                                 channels: BTreeMap::new(),
 753                                 our_node_id: our_pubkey,
 754                                 nodes: nodes,
 755                         }),
 756                         chain_monitor,
 757                         logger,
 758                 }
 759         }
 760
 761         /// Dumps the entire network view of this Router to the logger provided in the constructor at
 762         /// level Trace
 763         pub fn trace_state(&self) {
 764                 log_trace!(self, "{}", self.network_map.read().unwrap());
 765         }
 766
 767         /// Get network addresses by node id
 768         pub fn get_addresses(&self, pubkey: &PublicKey) -> Option<Vec<NetAddress>> {
 769                 let network = self.network_map.read().unwrap();
 770                 network.nodes.get(pubkey).map(|n| n.addresses.clone())
 771         }
 772
 773         /// Marks a node as having failed a route. This will avoid re-using the node in routes for now,
 774         /// with an exponential decay in node "badness". Note that there is deliberately no
 775         /// mark_channel_bad as a node may simply lie and suggest that an upstream channel from it is
 776         /// what failed the route and not the node itself. Instead, setting the blamed_upstream_node
 777         /// boolean will reduce the penalty, returning the node to usability faster. If the node is
 778         /// behaving correctly, it will disable the failing channel and we will use it again next time.
 779         pub fn mark_node_bad(&self, _node_id: &PublicKey, _blamed_upstream_node: bool) {
 780                 unimplemented!();
 781         }
 782
 783         fn remove_channel_in_nodes(nodes: &mut BTreeMap<PublicKey, NodeInfo>, chan: &ChannelInfo, short_channel_id: u64) {
 784                 macro_rules! remove_from_node {
 785                         ($node_id: expr) => {
 786                                 if let BtreeEntry::Occupied(mut entry) = nodes.entry($node_id) {
 787                                         entry.get_mut().channels.retain(|chan_id| {
 788                                                 short_channel_id != *NetworkMap::get_short_id(chan_id)
 789                                         });
 790                                         if entry.get().channels.is_empty() {
 791                                                 entry.remove_entry();
 792                                         }
 793                                 } else {
 794                                         panic!("Had channel that pointed to unknown node (ie inconsistent network map)!");
 795                                 }
 796                         }
 797                 }
 798                 remove_from_node!(chan.one_to_two.src_node_id);
 799                 remove_from_node!(chan.two_to_one.src_node_id);
 800         }
 801
 802         /// Gets a route from us to the given target node.
 803         ///
 804         /// Extra routing hops between known nodes and the target will be used if they are included in
 805         /// last_hops.
 806         ///
 807         /// If some channels aren't announced, it may be useful to fill in a first_hops with the
 808         /// results from a local ChannelManager::list_usable_channels() call. If it is filled in, our
 809         /// (this Router's) view of our local channels will be ignored, and only those in first_hops
 810         /// will be used.
 811         ///
 812         /// Panics if first_hops contains channels without short_channel_ids
 813         /// (ChannelManager::list_usable_channels will never include such channels).
 814         ///
 815         /// The fees on channels from us to next-hops are ignored (as they are assumed to all be
 816         /// equal), however the enabled/disabled bit on such channels as well as the htlc_minimum_msat
 817         /// *is* checked as they may change based on the receiving node.
 818         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> {
 819                 // TODO: Obviously *only* using total fee cost sucks. We should consider weighting by
 820                 // uptime/success in using a node in the past.
 821                 let network = self.network_map.read().unwrap();
 822
 823                 if *target == network.our_node_id {
 824                         return Err(LightningError{err: "Cannot generate a route to ourselves", action: ErrorAction::IgnoreError});
 825                 }
 826
 827                 if final_value_msat > 21_000_000 * 1_0000_0000 * 1000 {
 828                         return Err(LightningError{err: "Cannot generate a route of more value than all existing satoshis", action: ErrorAction::IgnoreError});
 829                 }
 830
 831                 // We do a dest-to-source Dijkstra's sorting by each node's distance from the destination
 832                 // plus the minimum per-HTLC fee to get from it to another node (aka "shitty A*").
 833                 // TODO: There are a few tweaks we could do, including possibly pre-calculating more stuff
 834                 // to use as the A* heuristic beyond just the cost to get one node further than the current
 835                 // one.
 836
 837                 let dummy_directional_info = DummyDirectionalChannelInfo { // used for first_hops routes
 838                         src_node_id: network.our_node_id.clone(),
 839                         cltv_expiry_delta: 0,
 840                         htlc_minimum_msat: 0,
 841                         fee_base_msat: 0,
 842                         fee_proportional_millionths: 0,
 843                 };
 844
 845                 let mut targets = BinaryHeap::new(); //TODO: Do we care about switching to eg Fibbonaci heap?
 846                 let mut dist = HashMap::with_capacity(network.nodes.len());
 847
 848                 let mut first_hop_targets = HashMap::with_capacity(if first_hops.is_some() { first_hops.as_ref().unwrap().len() } else { 0 });
 849                 if let Some(hops) = first_hops {
 850                         for chan in hops {
 851                                 let short_channel_id = chan.short_channel_id.expect("first_hops should be filled in with usable channels, not pending ones");
 852                                 if chan.remote_network_id == *target {
 853                                         return Ok(Route {
 854                                                 hops: vec![RouteHop {
 855                                                         pubkey: chan.remote_network_id,
 856                                                         node_features: NodeFeatures::with_known_relevant_init_flags(&chan.counterparty_features),
 857                                                         short_channel_id,
 858                                                         channel_features: ChannelFeatures::with_known_relevant_init_flags(&chan.counterparty_features),
 859                                                         fee_msat: final_value_msat,
 860                                                         cltv_expiry_delta: final_cltv,
 861                                                 }],
 862                                         });
 863                                 }
 864                                 first_hop_targets.insert(chan.remote_network_id, (short_channel_id, chan.counterparty_features.clone()));
 865                         }
 866                         if first_hop_targets.is_empty() {
 867                                 return Err(LightningError{err: "Cannot route when there are no outbound routes away from us", action: ErrorAction::IgnoreError});
 868                         }
 869                 }
 870
 871                 macro_rules! add_entry {
 872                         // Adds entry which goes from the node pointed to by $directional_info to
 873                         // $dest_node_id over the channel with id $chan_id with fees described in
 874                         // $directional_info.
 875                         ( $chan_id: expr, $dest_node_id: expr, $directional_info: expr, $chan_features: expr, $starting_fee_msat: expr ) => {
 876                                 //TODO: Explore simply adding fee to hit htlc_minimum_msat
 877                                 if $starting_fee_msat as u64 + final_value_msat >= $directional_info.htlc_minimum_msat {
 878                                         let proportional_fee_millions = ($starting_fee_msat + final_value_msat).checked_mul($directional_info.fee_proportional_millionths as u64);
 879                                         if let Some(new_fee) = proportional_fee_millions.and_then(|part| {
 880                                                         ($directional_info.fee_base_msat as u64).checked_add(part / 1000000) })
 881                                         {
 882                                                 let mut total_fee = $starting_fee_msat as u64;
 883                                                 let hm_entry = dist.entry(&$directional_info.src_node_id);
 884                                                 let old_entry = hm_entry.or_insert_with(|| {
 885                                                         let node = network.nodes.get(&$directional_info.src_node_id).unwrap();
 886                                                         (u64::max_value(),
 887                                                                 node.lowest_inbound_channel_fee_base_msat,
 888                                                                 node.lowest_inbound_channel_fee_proportional_millionths,
 889                                                                 RouteHop {
 890                                                                         pubkey: $dest_node_id.clone(),
 891                                                                         node_features: NodeFeatures::empty(),
 892                                                                         short_channel_id: 0,
 893                                                                         channel_features: $chan_features.clone(),
 894                                                                         fee_msat: 0,
 895                                                                         cltv_expiry_delta: 0,
 896                                                         })
 897                                                 });
 898                                                 if $directional_info.src_node_id != network.our_node_id {
 899                                                         // Ignore new_fee for channel-from-us as we assume all channels-from-us
 900                                                         // will have the same effective-fee
 901                                                         total_fee += new_fee;
 902                                                         if let Some(fee_inc) = final_value_msat.checked_add(total_fee).and_then(|inc| { (old_entry.2 as u64).checked_mul(inc) }) {
 903                                                                 total_fee += fee_inc / 1000000 + (old_entry.1 as u64);
 904                                                         } else {
 905                                                                 // max_value means we'll always fail the old_entry.0 > total_fee check
 906                                                                 total_fee = u64::max_value();
 907                                                         }
 908                                                 }
 909                                                 let new_graph_node = RouteGraphNode {
 910                                                         pubkey: $directional_info.src_node_id,
 911                                                         lowest_fee_to_peer_through_node: total_fee,
 912                                                         lowest_fee_to_node: $starting_fee_msat as u64 + new_fee,
 913                                                 };
 914                                                 if old_entry.0 > total_fee {
 915                                                         targets.push(new_graph_node);
 916                                                         old_entry.0 = total_fee;
 917                                                         old_entry.3 = RouteHop {
 918                                                                 pubkey: $dest_node_id.clone(),
 919                                                                 node_features: NodeFeatures::empty(),
 920                                                                 short_channel_id: $chan_id.clone(),
 921                                                                 channel_features: $chan_features.clone(),
 922                                                                 fee_msat: new_fee, // This field is ignored on the last-hop anyway
 923                                                                 cltv_expiry_delta: $directional_info.cltv_expiry_delta as u32,
 924                                                         }
 925                                                 }
 926                                         }
 927                                 }
 928                         };
 929                 }
 930
 931                 macro_rules! add_entries_to_cheapest_to_target_node {
 932                         ( $node: expr, $node_id: expr, $fee_to_target_msat: expr ) => {
 933                                 if first_hops.is_some() {
 934                                         if let Some(&(ref first_hop, ref features)) = first_hop_targets.get(&$node_id) {
 935                                                 add_entry!(first_hop, $node_id, dummy_directional_info, ChannelFeatures::with_known_relevant_init_flags(&features), $fee_to_target_msat);
 936                                         }
 937                                 }
 938
 939                                 if !$node.features.requires_unknown_bits() {
 940                                         for chan_id in $node.channels.iter() {
 941                                                 let chan = network.channels.get(chan_id).unwrap();
 942                                                 if !chan.features.requires_unknown_bits() {
 943                                                         if chan.one_to_two.src_node_id == *$node_id {
 944                                                                 // ie $node is one, ie next hop in A* is two, via the two_to_one channel
 945                                                                 if first_hops.is_none() || chan.two_to_one.src_node_id != network.our_node_id {
 946                                                                         if chan.two_to_one.enabled {
 947                                                                                 add_entry!(chan_id, chan.one_to_two.src_node_id, chan.two_to_one, chan.features, $fee_to_target_msat);
 948                                                                         }
 949                                                                 }
 950                                                         } else {
 951                                                                 if first_hops.is_none() || chan.one_to_two.src_node_id != network.our_node_id {
 952                                                                         if chan.one_to_two.enabled {
 953                                                                                 add_entry!(chan_id, chan.two_to_one.src_node_id, chan.one_to_two, chan.features, $fee_to_target_msat);
 954                                                                         }
 955                                                                 }
 956                                                         }
 957                                                 }
 958                                         }
 959                                 }
 960                         };
 961                 }
 962
 963                 match network.nodes.get(target) {
 964                         None => {},
 965                         Some(node) => {
 966                                 add_entries_to_cheapest_to_target_node!(node, target, 0);
 967                         },
 968                 }
 969
 970                 for hop in last_hops.iter() {
 971                         if first_hops.is_none() || hop.src_node_id != network.our_node_id { // first_hop overrules last_hops
 972                                 if network.nodes.get(&hop.src_node_id).is_some() {
 973                                         if first_hops.is_some() {
 974                                                 if let Some(&(ref first_hop, ref features)) = first_hop_targets.get(&hop.src_node_id) {
 975                                                         // Currently there are no channel-context features defined, so we are a
 976                                                         // bit lazy here. In the future, we should pull them out via our
 977                                                         // ChannelManager, but there's no reason to waste the space until we
 978                                                         // need them.
 979                                                         add_entry!(first_hop, hop.src_node_id, dummy_directional_info, ChannelFeatures::with_known_relevant_init_flags(&features), 0);
 980                                                 }
 981                                         }
 982                                         // BOLT 11 doesn't allow inclusion of features for the last hop hints, which
 983                                         // really sucks, cause we're gonna need that eventually.
 984                                         add_entry!(hop.short_channel_id, target, hop, ChannelFeatures::empty(), 0);
 985                                 }
 986                         }
 987                 }
 988
 989                 while let Some(RouteGraphNode { pubkey, lowest_fee_to_node, .. }) = targets.pop() {
 990                         if pubkey == network.our_node_id {
 991                                 let mut res = vec!(dist.remove(&network.our_node_id).unwrap().3);
 992                                 loop {
 993                                         if let Some(&(_, ref features)) = first_hop_targets.get(&res.last().unwrap().pubkey) {
 994                                                 res.last_mut().unwrap().node_features = NodeFeatures::with_known_relevant_init_flags(&features);
 995                                         } else if let Some(node) = network.nodes.get(&res.last().unwrap().pubkey) {
 996                                                 res.last_mut().unwrap().node_features = node.features.clone();
 997                                         } else {
 998                                                 // We should be able to fill in features for everything except the last
 999                                                 // hop, if the last hop was provided via a BOLT 11 invoice (though we
1000                                                 // should be able to extend it further as BOLT 11 does have feature
1001                                                 // flags for the last hop node itself).
1002                                                 assert!(res.last().unwrap().pubkey == *target);
1003                                         }
1004                                         if res.last().unwrap().pubkey == *target {
1005                                                 break;
1006                                         }
1007
1008                                         let new_entry = match dist.remove(&res.last().unwrap().pubkey) {
1009                                                 Some(hop) => hop.3,
1010                                                 None => return Err(LightningError{err: "Failed to find a non-fee-overflowing path to the given destination", action: ErrorAction::IgnoreError}),
1011                                         };
1012                                         res.last_mut().unwrap().fee_msat = new_entry.fee_msat;
1013                                         res.last_mut().unwrap().cltv_expiry_delta = new_entry.cltv_expiry_delta;
1014                                         res.push(new_entry);
1015                                 }
1016                                 res.last_mut().unwrap().fee_msat = final_value_msat;
1017                                 res.last_mut().unwrap().cltv_expiry_delta = final_cltv;
1018                                 let route = Route { hops: res };
1019                                 log_trace!(self, "Got route: {}", log_route!(route));
1020                                 return Ok(route);
1021                         }
1022
1023                         match network.nodes.get(&pubkey) {
1024                                 None => {},
1025                                 Some(node) => {
1026                                         add_entries_to_cheapest_to_target_node!(node, &pubkey, lowest_fee_to_node);
1027                                 },
1028                         }
1029                 }
1030
1031                 Err(LightningError{err: "Failed to find a path to the given destination", action: ErrorAction::IgnoreError})
1032         }
1033 }
1034
1035 #[cfg(test)]
1036 mod tests {
1037         use chain::chaininterface;
1038         use ln::channelmanager;
1039         use ln::router::{Router,NodeInfo,NetworkMap,ChannelInfo,DirectionalChannelInfo,RouteHint};
1040         use ln::features::{ChannelFeatures, InitFeatures, NodeFeatures};
1041         use ln::msgs::{LightningError, ErrorAction};
1042         use util::test_utils;
1043         use util::test_utils::TestVecWriter;
1044         use util::logger::Logger;
1045         use util::ser::{Writeable, Readable};
1046
1047         use bitcoin_hashes::sha256d::Hash as Sha256dHash;
1048         use bitcoin_hashes::Hash;
1049         use bitcoin::network::constants::Network;
1050
1051         use hex;
1052
1053         use secp256k1::key::{PublicKey,SecretKey};
1054         use secp256k1::Secp256k1;
1055
1056         use std::sync::Arc;
1057
1058         #[test]
1059         fn route_test() {
1060                 let secp_ctx = Secp256k1::new();
1061                 let our_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap());
1062                 let logger: Arc<Logger> = Arc::new(test_utils::TestLogger::new());
1063                 let chain_monitor = Arc::new(chaininterface::ChainWatchInterfaceUtil::new(Network::Testnet, Arc::clone(&logger)));
1064                 let router = Router::new(our_id, chain_monitor, Arc::clone(&logger));
1065
1066                 // Build network from our_id to node8:
1067                 //
1068                 //        -1(1)2-  node1  -1(3)2-
1069                 //       /                       \
1070                 // our_id -1(12)2- node8 -1(13)2--- node3
1071                 //       \                       /
1072                 //        -1(2)2-  node2  -1(4)2-
1073                 //
1074                 //
1075                 // chan1  1-to-2: disabled
1076                 // chan1  2-to-1: enabled, 0 fee
1077                 //
1078                 // chan2  1-to-2: enabled, ignored fee
1079                 // chan2  2-to-1: enabled, 0 fee
1080                 //
1081                 // chan3  1-to-2: enabled, 0 fee
1082                 // chan3  2-to-1: enabled, 100 msat fee
1083                 //
1084                 // chan4  1-to-2: enabled, 100% fee
1085                 // chan4  2-to-1: enabled, 0 fee
1086                 //
1087                 // chan12 1-to-2: enabled, ignored fee
1088                 // chan12 2-to-1: enabled, 0 fee
1089                 //
1090                 // chan13 1-to-2: enabled, 200% fee
1091                 // chan13 2-to-1: enabled, 0 fee
1092                 //
1093                 //
1094                 //       -1(5)2- node4 -1(8)2--
1095                 //       |         2          |
1096                 //       |       (11)         |
1097                 //      /          1           \
1098                 // node3--1(6)2- node5 -1(9)2--- node7 (not in global route map)
1099                 //      \                      /
1100                 //       -1(7)2- node6 -1(10)2-
1101                 //
1102                 // chan5  1-to-2: enabled, 100 msat fee
1103                 // chan5  2-to-1: enabled, 0 fee
1104                 //
1105                 // chan6  1-to-2: enabled, 0 fee
1106                 // chan6  2-to-1: enabled, 0 fee
1107                 //
1108                 // chan7  1-to-2: enabled, 100% fee
1109                 // chan7  2-to-1: enabled, 0 fee
1110                 //
1111                 // chan8  1-to-2: enabled, variable fee (0 then 1000 msat)
1112                 // chan8  2-to-1: enabled, 0 fee
1113                 //
1114                 // chan9  1-to-2: enabled, 1001 msat fee
1115                 // chan9  2-to-1: enabled, 0 fee
1116                 //
1117                 // chan10 1-to-2: enabled, 0 fee
1118                 // chan10 2-to-1: enabled, 0 fee
1119                 //
1120                 // chan11 1-to-2: enabled, 0 fee
1121                 // chan11 2-to-1: enabled, 0 fee
1122
1123                 let node1 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0202020202020202020202020202020202020202020202020202020202020202").unwrap()[..]).unwrap());
1124                 let node2 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0303030303030303030303030303030303030303030303030303030303030303").unwrap()[..]).unwrap());
1125                 let node3 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0404040404040404040404040404040404040404040404040404040404040404").unwrap()[..]).unwrap());
1126                 let node4 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0505050505050505050505050505050505050505050505050505050505050505").unwrap()[..]).unwrap());
1127                 let node5 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0606060606060606060606060606060606060606060606060606060606060606").unwrap()[..]).unwrap());
1128                 let node6 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0707070707070707070707070707070707070707070707070707070707070707").unwrap()[..]).unwrap());
1129                 let node7 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0808080808080808080808080808080808080808080808080808080808080808").unwrap()[..]).unwrap());
1130                 let node8 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0909090909090909090909090909090909090909090909090909090909090909").unwrap()[..]).unwrap());
1131
1132                 let zero_hash = Sha256dHash::hash(&[0; 32]);
1133
1134                 macro_rules! id_to_feature_flags {
1135                         // Set the feature flags to the id'th odd (ie non-required) feature bit so that we can
1136                         // test for it later.
1137                         ($id: expr) => { {
1138                                 let idx = ($id - 1) * 2 + 1;
1139                                 if idx > 8*3 {
1140                                         vec![1 << (idx - 8*3), 0, 0, 0]
1141                                 } else if idx > 8*2 {
1142                                         vec![1 << (idx - 8*2), 0, 0]
1143                                 } else if idx > 8*1 {
1144                                         vec![1 << (idx - 8*1), 0]
1145                                 } else {
1146                                         vec![1 << idx]
1147                                 }
1148                         } }
1149                 }
1150
1151                 {
1152                         let mut network = router.network_map.write().unwrap();
1153
1154                         network.nodes.insert(node1.clone(), NodeInfo {
1155                                 channels: vec!(NetworkMap::get_key(1, zero_hash.clone()), NetworkMap::get_key(3, zero_hash.clone())),
1156                                 lowest_inbound_channel_fee_base_msat: 100,
1157                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1158                                 features: NodeFeatures::from_le_bytes(id_to_feature_flags!(1)),
1159                                 last_update: Some(1),
1160                                 rgb: [0; 3],
1161                                 alias: [0; 32],
1162                                 addresses: Vec::new(),
1163                                 announcement_message: None,
1164                         });
1165                         network.channels.insert(NetworkMap::get_key(1, zero_hash.clone()), ChannelInfo {
1166                                 features: ChannelFeatures::from_le_bytes(id_to_feature_flags!(1)),
1167                                 one_to_two: DirectionalChannelInfo {
1168                                         src_node_id: our_id.clone(),
1169                                         last_update: 0,
1170                                         enabled: false,
1171                                         cltv_expiry_delta: u16::max_value(), // This value should be ignored
1172                                         htlc_minimum_msat: 0,
1173                                         fee_base_msat: u32::max_value(), // This value should be ignored
1174                                         fee_proportional_millionths: u32::max_value(), // This value should be ignored
1175                                         last_update_message: None,
1176                                 }, two_to_one: DirectionalChannelInfo {
1177                                         src_node_id: node1.clone(),
1178                                         last_update: 0,
1179                                         enabled: true,
1180                                         cltv_expiry_delta: 0,
1181                                         htlc_minimum_msat: 0,
1182                                         fee_base_msat: 0,
1183                                         fee_proportional_millionths: 0,
1184                                         last_update_message: None,
1185                                 },
1186                                 announcement_message: None,
1187                         });
1188                         network.nodes.insert(node2.clone(), NodeInfo {
1189                                 channels: vec!(NetworkMap::get_key(2, zero_hash.clone()), NetworkMap::get_key(4, zero_hash.clone())),
1190                                 lowest_inbound_channel_fee_base_msat: 0,
1191                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1192                                 features: NodeFeatures::from_le_bytes(id_to_feature_flags!(2)),
1193                                 last_update: Some(1),
1194                                 rgb: [0; 3],
1195                                 alias: [0; 32],
1196                                 addresses: Vec::new(),
1197                                 announcement_message: None,
1198                         });
1199                         network.channels.insert(NetworkMap::get_key(2, zero_hash.clone()), ChannelInfo {
1200                                 features: ChannelFeatures::from_le_bytes(id_to_feature_flags!(2)),
1201                                 one_to_two: DirectionalChannelInfo {
1202                                         src_node_id: our_id.clone(),
1203                                         last_update: 0,
1204                                         enabled: true,
1205                                         cltv_expiry_delta: u16::max_value(), // This value should be ignored
1206                                         htlc_minimum_msat: 0,
1207                                         fee_base_msat: u32::max_value(), // This value should be ignored
1208                                         fee_proportional_millionths: u32::max_value(), // This value should be ignored
1209                                         last_update_message: None,
1210                                 }, two_to_one: DirectionalChannelInfo {
1211                                         src_node_id: node2.clone(),
1212                                         last_update: 0,
1213                                         enabled: true,
1214                                         cltv_expiry_delta: 0,
1215                                         htlc_minimum_msat: 0,
1216                                         fee_base_msat: 0,
1217                                         fee_proportional_millionths: 0,
1218                                         last_update_message: None,
1219                                 },
1220                                 announcement_message: None,
1221                         });
1222                         network.nodes.insert(node8.clone(), NodeInfo {
1223                                 channels: vec!(NetworkMap::get_key(12, zero_hash.clone()), NetworkMap::get_key(13, zero_hash.clone())),
1224                                 lowest_inbound_channel_fee_base_msat: 0,
1225                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1226                                 features: NodeFeatures::from_le_bytes(id_to_feature_flags!(8)),
1227                                 last_update: Some(1),
1228                                 rgb: [0; 3],
1229                                 alias: [0; 32],
1230                                 addresses: Vec::new(),
1231                                 announcement_message: None,
1232                         });
1233                         network.channels.insert(NetworkMap::get_key(12, zero_hash.clone()), ChannelInfo {
1234                                 features: ChannelFeatures::from_le_bytes(id_to_feature_flags!(12)),
1235                                 one_to_two: DirectionalChannelInfo {
1236                                         src_node_id: our_id.clone(),
1237                                         last_update: 0,
1238                                         enabled: true,
1239                                         cltv_expiry_delta: u16::max_value(), // This value should be ignored
1240                                         htlc_minimum_msat: 0,
1241                                         fee_base_msat: u32::max_value(), // This value should be ignored
1242                                         fee_proportional_millionths: u32::max_value(), // This value should be ignored
1243                                         last_update_message: None,
1244                                 }, two_to_one: DirectionalChannelInfo {
1245                                         src_node_id: node8.clone(),
1246                                         last_update: 0,
1247                                         enabled: true,
1248                                         cltv_expiry_delta: 0,
1249                                         htlc_minimum_msat: 0,
1250                                         fee_base_msat: 0,
1251                                         fee_proportional_millionths: 0,
1252                                         last_update_message: None,
1253                                 },
1254                                 announcement_message: None,
1255                         });
1256                         network.nodes.insert(node3.clone(), NodeInfo {
1257                                 channels: vec!(
1258                                         NetworkMap::get_key(3, zero_hash.clone()),
1259                                         NetworkMap::get_key(4, zero_hash.clone()),
1260                                         NetworkMap::get_key(13, zero_hash.clone()),
1261                                         NetworkMap::get_key(5, zero_hash.clone()),
1262                                         NetworkMap::get_key(6, zero_hash.clone()),
1263                                         NetworkMap::get_key(7, zero_hash.clone())),
1264                                 lowest_inbound_channel_fee_base_msat: 0,
1265                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1266                                 features: NodeFeatures::from_le_bytes(id_to_feature_flags!(3)),
1267                                 last_update: Some(1),
1268                                 rgb: [0; 3],
1269                                 alias: [0; 32],
1270                                 addresses: Vec::new(),
1271                                 announcement_message: None,
1272                         });
1273                         network.channels.insert(NetworkMap::get_key(3, zero_hash.clone()), ChannelInfo {
1274                                 features: ChannelFeatures::from_le_bytes(id_to_feature_flags!(3)),
1275                                 one_to_two: DirectionalChannelInfo {
1276                                         src_node_id: node1.clone(),
1277                                         last_update: 0,
1278                                         enabled: true,
1279                                         cltv_expiry_delta: (3 << 8) | 1,
1280                                         htlc_minimum_msat: 0,
1281                                         fee_base_msat: 0,
1282                                         fee_proportional_millionths: 0,
1283                                         last_update_message: None,
1284                                 }, two_to_one: DirectionalChannelInfo {
1285                                         src_node_id: node3.clone(),
1286                                         last_update: 0,
1287                                         enabled: true,
1288                                         cltv_expiry_delta: (3 << 8) | 2,
1289                                         htlc_minimum_msat: 0,
1290                                         fee_base_msat: 100,
1291                                         fee_proportional_millionths: 0,
1292                                         last_update_message: None,
1293                                 },
1294                                 announcement_message: None,
1295                         });
1296                         network.channels.insert(NetworkMap::get_key(4, zero_hash.clone()), ChannelInfo {
1297                                 features: ChannelFeatures::from_le_bytes(id_to_feature_flags!(4)),
1298                                 one_to_two: DirectionalChannelInfo {
1299                                         src_node_id: node2.clone(),
1300                                         last_update: 0,
1301                                         enabled: true,
1302                                         cltv_expiry_delta: (4 << 8) | 1,
1303                                         htlc_minimum_msat: 0,
1304                                         fee_base_msat: 0,
1305                                         fee_proportional_millionths: 1000000,
1306                                         last_update_message: None,
1307                                 }, two_to_one: DirectionalChannelInfo {
1308                                         src_node_id: node3.clone(),
1309                                         last_update: 0,
1310                                         enabled: true,
1311                                         cltv_expiry_delta: (4 << 8) | 2,
1312                                         htlc_minimum_msat: 0,
1313                                         fee_base_msat: 0,
1314                                         fee_proportional_millionths: 0,
1315                                         last_update_message: None,
1316                                 },
1317                                 announcement_message: None,
1318                         });
1319                         network.channels.insert(NetworkMap::get_key(13, zero_hash.clone()), ChannelInfo {
1320                                 features: ChannelFeatures::from_le_bytes(id_to_feature_flags!(13)),
1321                                 one_to_two: DirectionalChannelInfo {
1322                                         src_node_id: node8.clone(),
1323                                         last_update: 0,
1324                                         enabled: true,
1325                                         cltv_expiry_delta: (13 << 8) | 1,
1326                                         htlc_minimum_msat: 0,
1327                                         fee_base_msat: 0,
1328                                         fee_proportional_millionths: 2000000,
1329                                         last_update_message: None,
1330                                 }, two_to_one: DirectionalChannelInfo {
1331                                         src_node_id: node3.clone(),
1332                                         last_update: 0,
1333                                         enabled: true,
1334                                         cltv_expiry_delta: (13 << 8) | 2,
1335                                         htlc_minimum_msat: 0,
1336                                         fee_base_msat: 0,
1337                                         fee_proportional_millionths: 0,
1338                                         last_update_message: None,
1339                                 },
1340                                 announcement_message: None,
1341                         });
1342                         network.nodes.insert(node4.clone(), NodeInfo {
1343                                 channels: vec!(NetworkMap::get_key(5, zero_hash.clone()), NetworkMap::get_key(11, zero_hash.clone())),
1344                                 lowest_inbound_channel_fee_base_msat: 0,
1345                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1346                                 features: NodeFeatures::from_le_bytes(id_to_feature_flags!(4)),
1347                                 last_update: Some(1),
1348                                 rgb: [0; 3],
1349                                 alias: [0; 32],
1350                                 addresses: Vec::new(),
1351                                 announcement_message: None,
1352                         });
1353                         network.channels.insert(NetworkMap::get_key(5, zero_hash.clone()), ChannelInfo {
1354                                 features: ChannelFeatures::from_le_bytes(id_to_feature_flags!(5)),
1355                                 one_to_two: DirectionalChannelInfo {
1356                                         src_node_id: node3.clone(),
1357                                         last_update: 0,
1358                                         enabled: true,
1359                                         cltv_expiry_delta: (5 << 8) | 1,
1360                                         htlc_minimum_msat: 0,
1361                                         fee_base_msat: 100,
1362                                         fee_proportional_millionths: 0,
1363                                         last_update_message: None,
1364                                 }, two_to_one: DirectionalChannelInfo {
1365                                         src_node_id: node4.clone(),
1366                                         last_update: 0,
1367                                         enabled: true,
1368                                         cltv_expiry_delta: (5 << 8) | 2,
1369                                         htlc_minimum_msat: 0,
1370                                         fee_base_msat: 0,
1371                                         fee_proportional_millionths: 0,
1372                                         last_update_message: None,
1373                                 },
1374                                 announcement_message: None,
1375                         });
1376                         network.nodes.insert(node5.clone(), NodeInfo {
1377                                 channels: vec!(NetworkMap::get_key(6, zero_hash.clone()), NetworkMap::get_key(11, zero_hash.clone())),
1378                                 lowest_inbound_channel_fee_base_msat: 0,
1379                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1380                                 features: NodeFeatures::from_le_bytes(id_to_feature_flags!(5)),
1381                                 last_update: Some(1),
1382                                 rgb: [0; 3],
1383                                 alias: [0; 32],
1384                                 addresses: Vec::new(),
1385                                 announcement_message: None,
1386                         });
1387                         network.channels.insert(NetworkMap::get_key(6, zero_hash.clone()), ChannelInfo {
1388                                 features: ChannelFeatures::from_le_bytes(id_to_feature_flags!(6)),
1389                                 one_to_two: DirectionalChannelInfo {
1390                                         src_node_id: node3.clone(),
1391                                         last_update: 0,
1392                                         enabled: true,
1393                                         cltv_expiry_delta: (6 << 8) | 1,
1394                                         htlc_minimum_msat: 0,
1395                                         fee_base_msat: 0,
1396                                         fee_proportional_millionths: 0,
1397                                         last_update_message: None,
1398                                 }, two_to_one: DirectionalChannelInfo {
1399                                         src_node_id: node5.clone(),
1400                                         last_update: 0,
1401                                         enabled: true,
1402                                         cltv_expiry_delta: (6 << 8) | 2,
1403                                         htlc_minimum_msat: 0,
1404                                         fee_base_msat: 0,
1405                                         fee_proportional_millionths: 0,
1406                                         last_update_message: None,
1407                                 },
1408                                 announcement_message: None,
1409                         });
1410                         network.channels.insert(NetworkMap::get_key(11, zero_hash.clone()), ChannelInfo {
1411                                 features: ChannelFeatures::from_le_bytes(id_to_feature_flags!(11)),
1412                                 one_to_two: DirectionalChannelInfo {
1413                                         src_node_id: node5.clone(),
1414                                         last_update: 0,
1415                                         enabled: true,
1416                                         cltv_expiry_delta: (11 << 8) | 1,
1417                                         htlc_minimum_msat: 0,
1418                                         fee_base_msat: 0,
1419                                         fee_proportional_millionths: 0,
1420                                         last_update_message: None,
1421                                 }, two_to_one: DirectionalChannelInfo {
1422                                         src_node_id: node4.clone(),
1423                                         last_update: 0,
1424                                         enabled: true,
1425                                         cltv_expiry_delta: (11 << 8) | 2,
1426                                         htlc_minimum_msat: 0,
1427                                         fee_base_msat: 0,
1428                                         fee_proportional_millionths: 0,
1429                                         last_update_message: None,
1430                                 },
1431                                 announcement_message: None,
1432                         });
1433                         network.nodes.insert(node6.clone(), NodeInfo {
1434                                 channels: vec!(NetworkMap::get_key(7, zero_hash.clone())),
1435                                 lowest_inbound_channel_fee_base_msat: 0,
1436                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1437                                 features: NodeFeatures::from_le_bytes(id_to_feature_flags!(6)),
1438                                 last_update: Some(1),
1439                                 rgb: [0; 3],
1440                                 alias: [0; 32],
1441                                 addresses: Vec::new(),
1442                                 announcement_message: None,
1443                         });
1444                         network.channels.insert(NetworkMap::get_key(7, zero_hash.clone()), ChannelInfo {
1445                                 features: ChannelFeatures::from_le_bytes(id_to_feature_flags!(7)),
1446                                 one_to_two: DirectionalChannelInfo {
1447                                         src_node_id: node3.clone(),
1448                                         last_update: 0,
1449                                         enabled: true,
1450                                         cltv_expiry_delta: (7 << 8) | 1,
1451                                         htlc_minimum_msat: 0,
1452                                         fee_base_msat: 0,
1453                                         fee_proportional_millionths: 1000000,
1454                                         last_update_message: None,
1455                                 }, two_to_one: DirectionalChannelInfo {
1456                                         src_node_id: node6.clone(),
1457                                         last_update: 0,
1458                                         enabled: true,
1459                                         cltv_expiry_delta: (7 << 8) | 2,
1460                                         htlc_minimum_msat: 0,
1461                                         fee_base_msat: 0,
1462                                         fee_proportional_millionths: 0,
1463                                         last_update_message: None,
1464                                 },
1465                                 announcement_message: None,
1466                         });
1467                 }
1468
1469                 { // Simple route to 3 via 2
1470                         let route = router.get_route(&node3, None, &Vec::new(), 100, 42).unwrap();
1471                         assert_eq!(route.hops.len(), 2);
1472
1473                         assert_eq!(route.hops[0].pubkey, node2);
1474                         assert_eq!(route.hops[0].short_channel_id, 2);
1475                         assert_eq!(route.hops[0].fee_msat, 100);
1476                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1477                         assert_eq!(route.hops[0].node_features.le_flags(), &id_to_feature_flags!(2));
1478                         assert_eq!(route.hops[0].channel_features.le_flags(), &id_to_feature_flags!(2));
1479
1480                         assert_eq!(route.hops[1].pubkey, node3);
1481                         assert_eq!(route.hops[1].short_channel_id, 4);
1482                         assert_eq!(route.hops[1].fee_msat, 100);
1483                         assert_eq!(route.hops[1].cltv_expiry_delta, 42);
1484                         assert_eq!(route.hops[1].node_features.le_flags(), &id_to_feature_flags!(3));
1485                         assert_eq!(route.hops[1].channel_features.le_flags(), &id_to_feature_flags!(4));
1486                 }
1487
1488                 { // Disable channels 4 and 12 by requiring unknown feature bits
1489                         let mut network = router.network_map.write().unwrap();
1490                         network.channels.get_mut(&NetworkMap::get_key(4, zero_hash.clone())).unwrap().features.set_require_unknown_bits();
1491                         network.channels.get_mut(&NetworkMap::get_key(12, zero_hash.clone())).unwrap().features.set_require_unknown_bits();
1492                 }
1493
1494                 { // If all the channels require some features we don't understand, route should fail
1495                         if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = router.get_route(&node3, None, &Vec::new(), 100, 42) {
1496                                 assert_eq!(err, "Failed to find a path to the given destination");
1497                         } else { panic!(); }
1498                 }
1499
1500                 { // If we specify a channel to node8, that overrides our local channel view and that gets used
1501                         let our_chans = vec![channelmanager::ChannelDetails {
1502                                 channel_id: [0; 32],
1503                                 short_channel_id: Some(42),
1504                                 remote_network_id: node8.clone(),
1505                                 counterparty_features: InitFeatures::from_le_bytes(vec![0b11]),
1506                                 channel_value_satoshis: 0,
1507                                 user_id: 0,
1508                                 outbound_capacity_msat: 0,
1509                                 inbound_capacity_msat: 0,
1510                                 is_live: true,
1511                         }];
1512                         let route = router.get_route(&node3, Some(&our_chans), &Vec::new(), 100, 42).unwrap();
1513                         assert_eq!(route.hops.len(), 2);
1514
1515                         assert_eq!(route.hops[0].pubkey, node8);
1516                         assert_eq!(route.hops[0].short_channel_id, 42);
1517                         assert_eq!(route.hops[0].fee_msat, 200);
1518                         assert_eq!(route.hops[0].cltv_expiry_delta, (13 << 8) | 1);
1519                         assert_eq!(route.hops[0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
1520                         assert_eq!(route.hops[0].channel_features.le_flags(), &Vec::new()); // No feature flags will meet the relevant-to-channel conversion
1521
1522                         assert_eq!(route.hops[1].pubkey, node3);
1523                         assert_eq!(route.hops[1].short_channel_id, 13);
1524                         assert_eq!(route.hops[1].fee_msat, 100);
1525                         assert_eq!(route.hops[1].cltv_expiry_delta, 42);
1526                         assert_eq!(route.hops[1].node_features.le_flags(), &id_to_feature_flags!(3));
1527                         assert_eq!(route.hops[1].channel_features.le_flags(), &id_to_feature_flags!(13));
1528                 }
1529
1530                 { // Re-enable channels 4 and 12 by wiping the unknown feature bits
1531                         let mut network = router.network_map.write().unwrap();
1532                         network.channels.get_mut(&NetworkMap::get_key(4, zero_hash.clone())).unwrap().features.clear_require_unknown_bits();
1533                         network.channels.get_mut(&NetworkMap::get_key(12, zero_hash.clone())).unwrap().features.clear_require_unknown_bits();
1534                 }
1535
1536                 { // Disable nodes 1, 2, and 8 by requiring unknown feature bits
1537                         let mut network = router.network_map.write().unwrap();
1538                         network.nodes.get_mut(&node1).unwrap().features.set_require_unknown_bits();
1539                         network.nodes.get_mut(&node2).unwrap().features.set_require_unknown_bits();
1540                         network.nodes.get_mut(&node8).unwrap().features.set_require_unknown_bits();
1541                 }
1542
1543                 { // If all nodes require some features we don't understand, route should fail
1544                         if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = router.get_route(&node3, None, &Vec::new(), 100, 42) {
1545                                 assert_eq!(err, "Failed to find a path to the given destination");
1546                         } else { panic!(); }
1547                 }
1548
1549                 { // If we specify a channel to node8, that overrides our local channel view and that gets used
1550                         let our_chans = vec![channelmanager::ChannelDetails {
1551                                 channel_id: [0; 32],
1552                                 short_channel_id: Some(42),
1553                                 remote_network_id: node8.clone(),
1554                                 counterparty_features: InitFeatures::from_le_bytes(vec![0b11]),
1555                                 channel_value_satoshis: 0,
1556                                 user_id: 0,
1557                                 outbound_capacity_msat: 0,
1558                                 inbound_capacity_msat: 0,
1559                                 is_live: true,
1560                         }];
1561                         let route = router.get_route(&node3, Some(&our_chans), &Vec::new(), 100, 42).unwrap();
1562                         assert_eq!(route.hops.len(), 2);
1563
1564                         assert_eq!(route.hops[0].pubkey, node8);
1565                         assert_eq!(route.hops[0].short_channel_id, 42);
1566                         assert_eq!(route.hops[0].fee_msat, 200);
1567                         assert_eq!(route.hops[0].cltv_expiry_delta, (13 << 8) | 1);
1568                         assert_eq!(route.hops[0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
1569                         assert_eq!(route.hops[0].channel_features.le_flags(), &Vec::new()); // No feature flags will meet the relevant-to-channel conversion
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                         assert_eq!(route.hops[1].node_features.le_flags(), &id_to_feature_flags!(3));
1576                         assert_eq!(route.hops[1].channel_features.le_flags(), &id_to_feature_flags!(13));
1577                 }
1578
1579                 { // Re-enable nodes 1, 2, and 8
1580                         let mut network = router.network_map.write().unwrap();
1581                         network.nodes.get_mut(&node1).unwrap().features.clear_require_unknown_bits();
1582                         network.nodes.get_mut(&node2).unwrap().features.clear_require_unknown_bits();
1583                         network.nodes.get_mut(&node8).unwrap().features.clear_require_unknown_bits();
1584                 }
1585
1586                 // Note that we don't test disabling node 3 and failing to route to it, as we (somewhat
1587                 // naively) assume that the user checked the feature bits on the invoice, which override
1588                 // the node_announcement.
1589
1590                 { // Route to 1 via 2 and 3 because our channel to 1 is disabled
1591                         let route = router.get_route(&node1, None, &Vec::new(), 100, 42).unwrap();
1592                         assert_eq!(route.hops.len(), 3);
1593
1594                         assert_eq!(route.hops[0].pubkey, node2);
1595                         assert_eq!(route.hops[0].short_channel_id, 2);
1596                         assert_eq!(route.hops[0].fee_msat, 200);
1597                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1598                         assert_eq!(route.hops[0].node_features.le_flags(), &id_to_feature_flags!(2));
1599                         assert_eq!(route.hops[0].channel_features.le_flags(), &id_to_feature_flags!(2));
1600
1601                         assert_eq!(route.hops[1].pubkey, node3);
1602                         assert_eq!(route.hops[1].short_channel_id, 4);
1603                         assert_eq!(route.hops[1].fee_msat, 100);
1604                         assert_eq!(route.hops[1].cltv_expiry_delta, (3 << 8) | 2);
1605                         assert_eq!(route.hops[1].node_features.le_flags(), &id_to_feature_flags!(3));
1606                         assert_eq!(route.hops[1].channel_features.le_flags(), &id_to_feature_flags!(4));
1607
1608                         assert_eq!(route.hops[2].pubkey, node1);
1609                         assert_eq!(route.hops[2].short_channel_id, 3);
1610                         assert_eq!(route.hops[2].fee_msat, 100);
1611                         assert_eq!(route.hops[2].cltv_expiry_delta, 42);
1612                         assert_eq!(route.hops[2].node_features.le_flags(), &id_to_feature_flags!(1));
1613                         assert_eq!(route.hops[2].channel_features.le_flags(), &id_to_feature_flags!(3));
1614                 }
1615
1616                 { // If we specify a channel to node8, that overrides our local channel view and that gets used
1617                         let our_chans = vec![channelmanager::ChannelDetails {
1618                                 channel_id: [0; 32],
1619                                 short_channel_id: Some(42),
1620                                 remote_network_id: node8.clone(),
1621                                 counterparty_features: InitFeatures::from_le_bytes(vec![0b11]),
1622                                 channel_value_satoshis: 0,
1623                                 user_id: 0,
1624                                 outbound_capacity_msat: 0,
1625                                 inbound_capacity_msat: 0,
1626                                 is_live: true,
1627                         }];
1628                         let route = router.get_route(&node3, Some(&our_chans), &Vec::new(), 100, 42).unwrap();
1629                         assert_eq!(route.hops.len(), 2);
1630
1631                         assert_eq!(route.hops[0].pubkey, node8);
1632                         assert_eq!(route.hops[0].short_channel_id, 42);
1633                         assert_eq!(route.hops[0].fee_msat, 200);
1634                         assert_eq!(route.hops[0].cltv_expiry_delta, (13 << 8) | 1);
1635                         assert_eq!(route.hops[0].node_features.le_flags(), &vec![0b11]);
1636                         assert_eq!(route.hops[0].channel_features.le_flags(), &Vec::new()); // No feature flags will meet the relevant-to-channel conversion
1637
1638                         assert_eq!(route.hops[1].pubkey, node3);
1639                         assert_eq!(route.hops[1].short_channel_id, 13);
1640                         assert_eq!(route.hops[1].fee_msat, 100);
1641                         assert_eq!(route.hops[1].cltv_expiry_delta, 42);
1642                         assert_eq!(route.hops[1].node_features.le_flags(), &id_to_feature_flags!(3));
1643                         assert_eq!(route.hops[1].channel_features.le_flags(), &id_to_feature_flags!(13));
1644                 }
1645
1646                 let mut last_hops = vec!(RouteHint {
1647                                 src_node_id: node4.clone(),
1648                                 short_channel_id: 8,
1649                                 fee_base_msat: 0,
1650                                 fee_proportional_millionths: 0,
1651                                 cltv_expiry_delta: (8 << 8) | 1,
1652                                 htlc_minimum_msat: 0,
1653                         }, RouteHint {
1654                                 src_node_id: node5.clone(),
1655                                 short_channel_id: 9,
1656                                 fee_base_msat: 1001,
1657                                 fee_proportional_millionths: 0,
1658                                 cltv_expiry_delta: (9 << 8) | 1,
1659                                 htlc_minimum_msat: 0,
1660                         }, RouteHint {
1661                                 src_node_id: node6.clone(),
1662                                 short_channel_id: 10,
1663                                 fee_base_msat: 0,
1664                                 fee_proportional_millionths: 0,
1665                                 cltv_expiry_delta: (10 << 8) | 1,
1666                                 htlc_minimum_msat: 0,
1667                         });
1668
1669                 { // Simple test across 2, 3, 5, and 4 via a last_hop channel
1670                         let route = router.get_route(&node7, None, &last_hops, 100, 42).unwrap();
1671                         assert_eq!(route.hops.len(), 5);
1672
1673                         assert_eq!(route.hops[0].pubkey, node2);
1674                         assert_eq!(route.hops[0].short_channel_id, 2);
1675                         assert_eq!(route.hops[0].fee_msat, 100);
1676                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1677                         assert_eq!(route.hops[0].node_features.le_flags(), &id_to_feature_flags!(2));
1678                         assert_eq!(route.hops[0].channel_features.le_flags(), &id_to_feature_flags!(2));
1679
1680                         assert_eq!(route.hops[1].pubkey, node3);
1681                         assert_eq!(route.hops[1].short_channel_id, 4);
1682                         assert_eq!(route.hops[1].fee_msat, 0);
1683                         assert_eq!(route.hops[1].cltv_expiry_delta, (6 << 8) | 1);
1684                         assert_eq!(route.hops[1].node_features.le_flags(), &id_to_feature_flags!(3));
1685                         assert_eq!(route.hops[1].channel_features.le_flags(), &id_to_feature_flags!(4));
1686
1687                         assert_eq!(route.hops[2].pubkey, node5);
1688                         assert_eq!(route.hops[2].short_channel_id, 6);
1689                         assert_eq!(route.hops[2].fee_msat, 0);
1690                         assert_eq!(route.hops[2].cltv_expiry_delta, (11 << 8) | 1);
1691                         assert_eq!(route.hops[2].node_features.le_flags(), &id_to_feature_flags!(5));
1692                         assert_eq!(route.hops[2].channel_features.le_flags(), &id_to_feature_flags!(6));
1693
1694                         assert_eq!(route.hops[3].pubkey, node4);
1695                         assert_eq!(route.hops[3].short_channel_id, 11);
1696                         assert_eq!(route.hops[3].fee_msat, 0);
1697                         assert_eq!(route.hops[3].cltv_expiry_delta, (8 << 8) | 1);
1698                         // If we have a peer in the node map, we'll use their features here since we don't have
1699                         // a way of figuring out their features from the invoice:
1700                         assert_eq!(route.hops[3].node_features.le_flags(), &id_to_feature_flags!(4));
1701                         assert_eq!(route.hops[3].channel_features.le_flags(), &id_to_feature_flags!(11));
1702
1703                         assert_eq!(route.hops[4].pubkey, node7);
1704                         assert_eq!(route.hops[4].short_channel_id, 8);
1705                         assert_eq!(route.hops[4].fee_msat, 100);
1706                         assert_eq!(route.hops[4].cltv_expiry_delta, 42);
1707                         assert_eq!(route.hops[4].node_features.le_flags(), &Vec::new()); // We dont pass flags in from invoices yet
1708                         assert_eq!(route.hops[4].channel_features.le_flags(), &Vec::new()); // We can't learn any flags from invoices, sadly
1709                 }
1710
1711                 { // Simple test with outbound channel to 4 to test that last_hops and first_hops connect
1712                         let our_chans = vec![channelmanager::ChannelDetails {
1713                                 channel_id: [0; 32],
1714                                 short_channel_id: Some(42),
1715                                 remote_network_id: node4.clone(),
1716                                 counterparty_features: InitFeatures::from_le_bytes(vec![0b11]),
1717                                 channel_value_satoshis: 0,
1718                                 user_id: 0,
1719                                 outbound_capacity_msat: 0,
1720                                 inbound_capacity_msat: 0,
1721                                 is_live: true,
1722                         }];
1723                         let route = router.get_route(&node7, Some(&our_chans), &last_hops, 100, 42).unwrap();
1724                         assert_eq!(route.hops.len(), 2);
1725
1726                         assert_eq!(route.hops[0].pubkey, node4);
1727                         assert_eq!(route.hops[0].short_channel_id, 42);
1728                         assert_eq!(route.hops[0].fee_msat, 0);
1729                         assert_eq!(route.hops[0].cltv_expiry_delta, (8 << 8) | 1);
1730                         assert_eq!(route.hops[0].node_features.le_flags(), &vec![0b11]);
1731                         assert_eq!(route.hops[0].channel_features.le_flags(), &Vec::new()); // No feature flags will meet the relevant-to-channel conversion
1732
1733                         assert_eq!(route.hops[1].pubkey, node7);
1734                         assert_eq!(route.hops[1].short_channel_id, 8);
1735                         assert_eq!(route.hops[1].fee_msat, 100);
1736                         assert_eq!(route.hops[1].cltv_expiry_delta, 42);
1737                         assert_eq!(route.hops[1].node_features.le_flags(), &Vec::new()); // We dont pass flags in from invoices yet
1738                         assert_eq!(route.hops[1].channel_features.le_flags(), &Vec::new()); // We can't learn any flags from invoices, sadly
1739                 }
1740
1741                 last_hops[0].fee_base_msat = 1000;
1742
1743                 { // Revert to via 6 as the fee on 8 goes up
1744                         let route = router.get_route(&node7, None, &last_hops, 100, 42).unwrap();
1745                         assert_eq!(route.hops.len(), 4);
1746
1747                         assert_eq!(route.hops[0].pubkey, node2);
1748                         assert_eq!(route.hops[0].short_channel_id, 2);
1749                         assert_eq!(route.hops[0].fee_msat, 200); // fee increased as its % of value transferred across node
1750                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1751                         assert_eq!(route.hops[0].node_features.le_flags(), &id_to_feature_flags!(2));
1752                         assert_eq!(route.hops[0].channel_features.le_flags(), &id_to_feature_flags!(2));
1753
1754                         assert_eq!(route.hops[1].pubkey, node3);
1755                         assert_eq!(route.hops[1].short_channel_id, 4);
1756                         assert_eq!(route.hops[1].fee_msat, 100);
1757                         assert_eq!(route.hops[1].cltv_expiry_delta, (7 << 8) | 1);
1758                         assert_eq!(route.hops[1].node_features.le_flags(), &id_to_feature_flags!(3));
1759                         assert_eq!(route.hops[1].channel_features.le_flags(), &id_to_feature_flags!(4));
1760
1761                         assert_eq!(route.hops[2].pubkey, node6);
1762                         assert_eq!(route.hops[2].short_channel_id, 7);
1763                         assert_eq!(route.hops[2].fee_msat, 0);
1764                         assert_eq!(route.hops[2].cltv_expiry_delta, (10 << 8) | 1);
1765                         // If we have a peer in the node map, we'll use their features here since we don't have
1766                         // a way of figuring out their features from the invoice:
1767                         assert_eq!(route.hops[2].node_features.le_flags(), &id_to_feature_flags!(6));
1768                         assert_eq!(route.hops[2].channel_features.le_flags(), &id_to_feature_flags!(7));
1769
1770                         assert_eq!(route.hops[3].pubkey, node7);
1771                         assert_eq!(route.hops[3].short_channel_id, 10);
1772                         assert_eq!(route.hops[3].fee_msat, 100);
1773                         assert_eq!(route.hops[3].cltv_expiry_delta, 42);
1774                         assert_eq!(route.hops[3].node_features.le_flags(), &Vec::new()); // We dont pass flags in from invoices yet
1775                         assert_eq!(route.hops[3].channel_features.le_flags(), &Vec::new()); // We can't learn any flags from invoices, sadly
1776                 }
1777
1778                 { // ...but still use 8 for larger payments as 6 has a variable feerate
1779                         let route = router.get_route(&node7, None, &last_hops, 2000, 42).unwrap();
1780                         assert_eq!(route.hops.len(), 5);
1781
1782                         assert_eq!(route.hops[0].pubkey, node2);
1783                         assert_eq!(route.hops[0].short_channel_id, 2);
1784                         assert_eq!(route.hops[0].fee_msat, 3000);
1785                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1786                         assert_eq!(route.hops[0].node_features.le_flags(), &id_to_feature_flags!(2));
1787                         assert_eq!(route.hops[0].channel_features.le_flags(), &id_to_feature_flags!(2));
1788
1789                         assert_eq!(route.hops[1].pubkey, node3);
1790                         assert_eq!(route.hops[1].short_channel_id, 4);
1791                         assert_eq!(route.hops[1].fee_msat, 0);
1792                         assert_eq!(route.hops[1].cltv_expiry_delta, (6 << 8) | 1);
1793                         assert_eq!(route.hops[1].node_features.le_flags(), &id_to_feature_flags!(3));
1794                         assert_eq!(route.hops[1].channel_features.le_flags(), &id_to_feature_flags!(4));
1795
1796                         assert_eq!(route.hops[2].pubkey, node5);
1797                         assert_eq!(route.hops[2].short_channel_id, 6);
1798                         assert_eq!(route.hops[2].fee_msat, 0);
1799                         assert_eq!(route.hops[2].cltv_expiry_delta, (11 << 8) | 1);
1800                         assert_eq!(route.hops[2].node_features.le_flags(), &id_to_feature_flags!(5));
1801                         assert_eq!(route.hops[2].channel_features.le_flags(), &id_to_feature_flags!(6));
1802
1803                         assert_eq!(route.hops[3].pubkey, node4);
1804                         assert_eq!(route.hops[3].short_channel_id, 11);
1805                         assert_eq!(route.hops[3].fee_msat, 1000);
1806                         assert_eq!(route.hops[3].cltv_expiry_delta, (8 << 8) | 1);
1807                         // If we have a peer in the node map, we'll use their features here since we don't have
1808                         // a way of figuring out their features from the invoice:
1809                         assert_eq!(route.hops[3].node_features.le_flags(), &id_to_feature_flags!(4));
1810                         assert_eq!(route.hops[3].channel_features.le_flags(), &id_to_feature_flags!(11));
1811
1812                         assert_eq!(route.hops[4].pubkey, node7);
1813                         assert_eq!(route.hops[4].short_channel_id, 8);
1814                         assert_eq!(route.hops[4].fee_msat, 2000);
1815                         assert_eq!(route.hops[4].cltv_expiry_delta, 42);
1816                         assert_eq!(route.hops[4].node_features.le_flags(), &Vec::new()); // We dont pass flags in from invoices yet
1817                         assert_eq!(route.hops[4].channel_features.le_flags(), &Vec::new()); // We can't learn any flags from invoices, sadly
1818                 }
1819
1820                 { // Test Router serialization/deserialization
1821                         let mut w = TestVecWriter(Vec::new());
1822                         let network = router.network_map.read().unwrap();
1823                         assert!(!network.channels.is_empty());
1824                         assert!(!network.nodes.is_empty());
1825                         network.write(&mut w).unwrap();
1826                         assert!(<NetworkMap>::read(&mut ::std::io::Cursor::new(&w.0)).unwrap() == *network);
1827                 }
1828         }
1829 }