_ 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::sync::atomic::{AtomicUsize, Ordering};
  26 use std::collections::{HashMap,BinaryHeap,BTreeMap};
  27 use std::collections::btree_map::Entry as BtreeEntry;
  28 use std;
  29
  30 /// A hop in a route
  31 #[derive(Clone, PartialEq)]
  32 pub struct RouteHop {
  33         /// The node_id of the node at this hop.
  34         pub pubkey: PublicKey,
  35         /// The node_announcement features of the node at this hop. For the last hop, these may be
  36         /// amended to match the features present in the invoice this node generated.
  37         pub node_features: NodeFeatures,
  38         /// The channel that should be used from the previous hop to reach this node.
  39         pub short_channel_id: u64,
  40         /// The channel_announcement features of the channel that should be used from the previous hop
  41         /// to reach this node.
  42         pub channel_features: ChannelFeatures,
  43         /// The fee taken on this hop. For the last hop, this should be the full value of the payment.
  44         pub fee_msat: u64,
  45         /// The CLTV delta added for this hop. For the last hop, this should be the full CLTV value
  46         /// expected at the destination, in excess of the current block height.
  47         pub cltv_expiry_delta: u32,
  48 }
  49
  50 /// A route from us through the network to a destination
  51 #[derive(Clone, PartialEq)]
  52 pub struct Route {
  53         /// The list of hops, NOT INCLUDING our own, where the last hop is the destination. Thus, this
  54         /// must always be at least length one. By protocol rules, this may not currently exceed 20 in
  55         /// length.
  56         pub hops: Vec<RouteHop>,
  57 }
  58
  59 impl Writeable for Route {
  60         fn write<W: ::util::ser::Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
  61                 (self.hops.len() as u8).write(writer)?;
  62                 for hop in self.hops.iter() {
  63                         hop.pubkey.write(writer)?;
  64                         hop.node_features.write(writer)?;
  65                         hop.short_channel_id.write(writer)?;
  66                         hop.channel_features.write(writer)?;
  67                         hop.fee_msat.write(writer)?;
  68                         hop.cltv_expiry_delta.write(writer)?;
  69                 }
  70                 Ok(())
  71         }
  72 }
  73
  74 impl<R: ::std::io::Read> Readable<R> for Route {
  75         fn read(reader: &mut R) -> Result<Route, DecodeError> {
  76                 let hops_count: u8 = Readable::read(reader)?;
  77                 let mut hops = Vec::with_capacity(hops_count as usize);
  78                 for _ in 0..hops_count {
  79                         hops.push(RouteHop {
  80                                 pubkey: Readable::read(reader)?,
  81                                 node_features: Readable::read(reader)?,
  82                                 short_channel_id: Readable::read(reader)?,
  83                                 channel_features: Readable::read(reader)?,
  84                                 fee_msat: Readable::read(reader)?,
  85                                 cltv_expiry_delta: Readable::read(reader)?,
  86                         });
  87                 }
  88                 Ok(Route {
  89                         hops
  90                 })
  91         }
  92 }
  93
  94 #[derive(PartialEq)]
  95 struct DirectionalChannelInfo {
  96         src_node_id: PublicKey,
  97         last_update: u32,
  98         enabled: bool,
  99         cltv_expiry_delta: u16,
 100         htlc_minimum_msat: u64,
 101         fee_base_msat: u32,
 102         fee_proportional_millionths: u32,
 103         last_update_message: Option<msgs::ChannelUpdate>,
 104 }
 105
 106 impl std::fmt::Display for DirectionalChannelInfo {
 107         fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
 108                 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)?;
 109                 Ok(())
 110         }
 111 }
 112
 113 impl_writeable!(DirectionalChannelInfo, 0, {
 114         src_node_id,
 115         last_update,
 116         enabled,
 117         cltv_expiry_delta,
 118         htlc_minimum_msat,
 119         fee_base_msat,
 120         fee_proportional_millionths,
 121         last_update_message
 122 });
 123
 124 #[derive(PartialEq)]
 125 struct ChannelInfo {
 126         features: ChannelFeatures,
 127         one_to_two: DirectionalChannelInfo,
 128         two_to_one: DirectionalChannelInfo,
 129         //this is cached here so we can send out it later if required by route_init_sync
 130         //keep an eye on this to see if the extra memory is a problem
 131         announcement_message: Option<msgs::ChannelAnnouncement>,
 132 }
 133
 134 impl std::fmt::Display for ChannelInfo {
 135         fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
 136                 write!(f, "features: {}, one_to_two: {}, two_to_one: {}", log_bytes!(self.features.encode()), self.one_to_two, self.two_to_one)?;
 137                 Ok(())
 138         }
 139 }
 140
 141 impl_writeable!(ChannelInfo, 0, {
 142         features,
 143         one_to_two,
 144         two_to_one,
 145         announcement_message
 146 });
 147
 148 #[derive(PartialEq)]
 149 struct NodeInfo {
 150         #[cfg(feature = "non_bitcoin_chain_hash_routing")]
 151         channels: Vec<(u64, Sha256dHash)>,
 152         #[cfg(not(feature = "non_bitcoin_chain_hash_routing"))]
 153         channels: Vec<u64>,
 154
 155         lowest_inbound_channel_fee_base_msat: u32,
 156         lowest_inbound_channel_fee_proportional_millionths: u32,
 157
 158         features: NodeFeatures,
 159         last_update: u32,
 160         rgb: [u8; 3],
 161         alias: [u8; 32],
 162         addresses: Vec<NetAddress>,
 163         //this is cached here so we can send out it later if required by route_init_sync
 164         //keep an eye on this to see if the extra memory is a problem
 165         announcement_message: Option<msgs::NodeAnnouncement>,
 166 }
 167
 168 impl std::fmt::Display for NodeInfo {
 169         fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
 170                 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[..])?;
 171                 Ok(())
 172         }
 173 }
 174
 175 impl Writeable for NodeInfo {
 176         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 177                 (self.channels.len() as u64).write(writer)?;
 178                 for ref chan in self.channels.iter() {
 179                         chan.write(writer)?;
 180                 }
 181                 self.lowest_inbound_channel_fee_base_msat.write(writer)?;
 182                 self.lowest_inbound_channel_fee_proportional_millionths.write(writer)?;
 183                 self.features.write(writer)?;
 184                 self.last_update.write(writer)?;
 185                 self.rgb.write(writer)?;
 186                 self.alias.write(writer)?;
 187                 (self.addresses.len() as u64).write(writer)?;
 188                 for ref addr in &self.addresses {
 189                         addr.write(writer)?;
 190                 }
 191                 self.announcement_message.write(writer)?;
 192                 Ok(())
 193         }
 194 }
 195
 196 const MAX_ALLOC_SIZE: u64 = 64*1024;
 197
 198 impl<R: ::std::io::Read> Readable<R> for NodeInfo {
 199         fn read(reader: &mut R) -> Result<NodeInfo, DecodeError> {
 200                 let channels_count: u64 = Readable::read(reader)?;
 201                 let mut channels = Vec::with_capacity(cmp::min(channels_count, MAX_ALLOC_SIZE / 8) as usize);
 202                 for _ in 0..channels_count {
 203                         channels.push(Readable::read(reader)?);
 204                 }
 205                 let lowest_inbound_channel_fee_base_msat = Readable::read(reader)?;
 206                 let lowest_inbound_channel_fee_proportional_millionths = Readable::read(reader)?;
 207                 let features = Readable::read(reader)?;
 208                 let last_update = Readable::read(reader)?;
 209                 let rgb = Readable::read(reader)?;
 210                 let alias = Readable::read(reader)?;
 211                 let addresses_count: u64 = Readable::read(reader)?;
 212                 let mut addresses = Vec::with_capacity(cmp::min(addresses_count, MAX_ALLOC_SIZE / 40) as usize);
 213                 for _ in 0..addresses_count {
 214                         match Readable::read(reader) {
 215                                 Ok(Ok(addr)) => { addresses.push(addr); },
 216                                 Ok(Err(_)) => return Err(DecodeError::InvalidValue),
 217                                 Err(DecodeError::ShortRead) => return Err(DecodeError::BadLengthDescriptor),
 218                                 _ => unreachable!(),
 219                         }
 220                 }
 221                 let announcement_message = Readable::read(reader)?;
 222                 Ok(NodeInfo {
 223                         channels,
 224                         lowest_inbound_channel_fee_base_msat,
 225                         lowest_inbound_channel_fee_proportional_millionths,
 226                         features,
 227                         last_update,
 228                         rgb,
 229                         alias,
 230                         addresses,
 231                         announcement_message
 232                 })
 233         }
 234 }
 235
 236 #[derive(PartialEq)]
 237 struct NetworkMap {
 238         #[cfg(feature = "non_bitcoin_chain_hash_routing")]
 239         channels: BTreeMap<(u64, Sha256dHash), ChannelInfo>,
 240         #[cfg(not(feature = "non_bitcoin_chain_hash_routing"))]
 241         channels: BTreeMap<u64, ChannelInfo>,
 242
 243         our_node_id: PublicKey,
 244         nodes: BTreeMap<PublicKey, NodeInfo>,
 245 }
 246
 247 impl Writeable for NetworkMap {
 248         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 249                 (self.channels.len() as u64).write(writer)?;
 250                 for (ref chan_id, ref chan_info) in self.channels.iter() {
 251                         (*chan_id).write(writer)?;
 252                         chan_info.write(writer)?;
 253                 }
 254                 self.our_node_id.write(writer)?;
 255                 (self.nodes.len() as u64).write(writer)?;
 256                 for (ref node_id, ref node_info) in self.nodes.iter() {
 257                         node_id.write(writer)?;
 258                         node_info.write(writer)?;
 259                 }
 260                 Ok(())
 261         }
 262 }
 263
 264 impl<R: ::std::io::Read> Readable<R> for NetworkMap {
 265         fn read(reader: &mut R) -> Result<NetworkMap, DecodeError> {
 266                 let channels_count: u64 = Readable::read(reader)?;
 267                 let mut channels = BTreeMap::new();
 268                 for _ in 0..channels_count {
 269                         let chan_id: u64 = Readable::read(reader)?;
 270                         let chan_info = Readable::read(reader)?;
 271                         channels.insert(chan_id, chan_info);
 272                 }
 273                 let our_node_id = Readable::read(reader)?;
 274                 let nodes_count: u64 = Readable::read(reader)?;
 275                 let mut nodes = BTreeMap::new();
 276                 for _ in 0..nodes_count {
 277                         let node_id = Readable::read(reader)?;
 278                         let node_info = Readable::read(reader)?;
 279                         nodes.insert(node_id, node_info);
 280                 }
 281                 Ok(NetworkMap {
 282                         channels,
 283                         our_node_id,
 284                         nodes,
 285                 })
 286         }
 287 }
 288
 289 impl std::fmt::Display for NetworkMap {
 290         fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
 291                 write!(f, "Node id {} network map\n[Channels]\n", log_pubkey!(self.our_node_id))?;
 292                 for (key, val) in self.channels.iter() {
 293                         write!(f, " {}: {}\n", key, val)?;
 294                 }
 295                 write!(f, "[Nodes]\n")?;
 296                 for (key, val) in self.nodes.iter() {
 297                         write!(f, " {}: {}\n", log_pubkey!(key), val)?;
 298                 }
 299                 Ok(())
 300         }
 301 }
 302
 303 impl NetworkMap {
 304         #[cfg(feature = "non_bitcoin_chain_hash_routing")]
 305         #[inline]
 306         fn get_key(short_channel_id: u64, chain_hash: Sha256dHash) -> (u64, Sha256dHash) {
 307                 (short_channel_id, chain_hash)
 308         }
 309
 310         #[cfg(not(feature = "non_bitcoin_chain_hash_routing"))]
 311         #[inline]
 312         fn get_key(short_channel_id: u64, _: Sha256dHash) -> u64 {
 313                 short_channel_id
 314         }
 315
 316         #[cfg(feature = "non_bitcoin_chain_hash_routing")]
 317         #[inline]
 318         fn get_short_id(id: &(u64, Sha256dHash)) -> &u64 {
 319                 &id.0
 320         }
 321
 322         #[cfg(not(feature = "non_bitcoin_chain_hash_routing"))]
 323         #[inline]
 324         fn get_short_id(id: &u64) -> &u64 {
 325                 id
 326         }
 327 }
 328
 329 /// A channel descriptor which provides a last-hop route to get_route
 330 pub struct RouteHint {
 331         /// The node_id of the non-target end of the route
 332         pub src_node_id: PublicKey,
 333         /// The short_channel_id of this channel
 334         pub short_channel_id: u64,
 335         /// The static msat-denominated fee which must be paid to use this channel
 336         pub fee_base_msat: u32,
 337         /// The dynamic proportional fee which must be paid to use this channel, denominated in
 338         /// millionths of the value being forwarded to the next hop.
 339         pub fee_proportional_millionths: u32,
 340         /// The difference in CLTV values between this node and the next node.
 341         pub cltv_expiry_delta: u16,
 342         /// The minimum value, in msat, which must be relayed to the next hop.
 343         pub htlc_minimum_msat: u64,
 344 }
 345
 346 /// Tracks a view of the network, receiving updates from peers and generating Routes to
 347 /// payment destinations.
 348 pub struct Router {
 349         secp_ctx: Secp256k1<secp256k1::VerifyOnly>,
 350         network_map: RwLock<NetworkMap>,
 351         full_syncs_requested: AtomicUsize,
 352         chain_monitor: Arc<ChainWatchInterface>,
 353         logger: Arc<Logger>,
 354 }
 355
 356 const SERIALIZATION_VERSION: u8 = 1;
 357 const MIN_SERIALIZATION_VERSION: u8 = 1;
 358
 359 impl Writeable for Router {
 360         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 361                 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
 362                 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
 363
 364                 let network = self.network_map.read().unwrap();
 365                 network.write(writer)?;
 366                 Ok(())
 367         }
 368 }
 369
 370 /// Arguments for the creation of a Router that are not deserialized.
 371 /// At a high-level, the process for deserializing a Router and resuming normal operation is:
 372 /// 1) Deserialize the Router by filling in this struct and calling <Router>::read(reaser, args).
 373 /// 2) Register the new Router with your ChainWatchInterface
 374 pub struct RouterReadArgs {
 375         /// The ChainWatchInterface for use in the Router in the future.
 376         ///
 377         /// No calls to the ChainWatchInterface will be made during deserialization.
 378         pub chain_monitor: Arc<ChainWatchInterface>,
 379         /// The Logger for use in the ChannelManager and which may be used to log information during
 380         /// deserialization.
 381         pub logger: Arc<Logger>,
 382 }
 383
 384 impl<R: ::std::io::Read> ReadableArgs<R, RouterReadArgs> for Router {
 385         fn read(reader: &mut R, args: RouterReadArgs) -> Result<Router, DecodeError> {
 386                 let _ver: u8 = Readable::read(reader)?;
 387                 let min_ver: u8 = Readable::read(reader)?;
 388                 if min_ver > SERIALIZATION_VERSION {
 389                         return Err(DecodeError::UnknownVersion);
 390                 }
 391                 let network_map = Readable::read(reader)?;
 392                 Ok(Router {
 393                         secp_ctx: Secp256k1::verification_only(),
 394                         network_map: RwLock::new(network_map),
 395                         full_syncs_requested: AtomicUsize::new(0),
 396                         chain_monitor: args.chain_monitor,
 397                         logger: args.logger,
 398                 })
 399         }
 400 }
 401
 402 macro_rules! secp_verify_sig {
 403         ( $secp_ctx: expr, $msg: expr, $sig: expr, $pubkey: expr ) => {
 404                 match $secp_ctx.verify($msg, $sig, $pubkey) {
 405                         Ok(_) => {},
 406                         Err(_) => return Err(LightningError{err: "Invalid signature from remote node", action: ErrorAction::IgnoreError}),
 407                 }
 408         };
 409 }
 410
 411 impl RoutingMessageHandler for Router {
 412
 413         fn handle_node_announcement(&self, msg: &msgs::NodeAnnouncement) -> Result<bool, LightningError> {
 414                 let msg_hash = hash_to_message!(&Sha256dHash::hash(&msg.contents.encode()[..])[..]);
 415                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.signature, &msg.contents.node_id);
 416
 417                 let mut network = self.network_map.write().unwrap();
 418                 match network.nodes.get_mut(&msg.contents.node_id) {
 419                         None => Err(LightningError{err: "No existing channels for node_announcement", action: ErrorAction::IgnoreError}),
 420                         Some(node) => {
 421                                 if node.last_update >= msg.contents.timestamp {
 422                                         return Err(LightningError{err: "Update older than last processed update", action: ErrorAction::IgnoreError});
 423                                 }
 424
 425                                 node.features = msg.contents.features.clone();
 426                                 node.last_update = msg.contents.timestamp;
 427                                 node.rgb = msg.contents.rgb;
 428                                 node.alias = msg.contents.alias;
 429                                 node.addresses = msg.contents.addresses.clone();
 430
 431                                 let should_relay = msg.contents.excess_data.is_empty() && msg.contents.excess_address_data.is_empty();
 432                                 node.announcement_message = if should_relay { Some(msg.clone()) } else { None };
 433                                 Ok(should_relay)
 434                         }
 435                 }
 436         }
 437
 438         fn handle_channel_announcement(&self, msg: &msgs::ChannelAnnouncement) -> Result<bool, LightningError> {
 439                 if msg.contents.node_id_1 == msg.contents.node_id_2 || msg.contents.bitcoin_key_1 == msg.contents.bitcoin_key_2 {
 440                         return Err(LightningError{err: "Channel announcement node had a channel with itself", action: ErrorAction::IgnoreError});
 441                 }
 442
 443                 let msg_hash = hash_to_message!(&Sha256dHash::hash(&msg.contents.encode()[..])[..]);
 444                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.node_signature_1, &msg.contents.node_id_1);
 445                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.node_signature_2, &msg.contents.node_id_2);
 446                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.bitcoin_signature_1, &msg.contents.bitcoin_key_1);
 447                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.bitcoin_signature_2, &msg.contents.bitcoin_key_2);
 448
 449                 let checked_utxo = match self.chain_monitor.get_chain_utxo(msg.contents.chain_hash, msg.contents.short_channel_id) {
 450                         Ok((script_pubkey, _value)) => {
 451                                 let expected_script = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
 452                                                                     .push_slice(&msg.contents.bitcoin_key_1.serialize())
 453                                                                     .push_slice(&msg.contents.bitcoin_key_2.serialize())
 454                                                                     .push_opcode(opcodes::all::OP_PUSHNUM_2)
 455                                                                     .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
 456                                 if script_pubkey != expected_script {
 457                                         return Err(LightningError{err: "Channel announcement keys didn't match on-chain script", action: ErrorAction::IgnoreError});
 458                                 }
 459                                 //TODO: Check if value is worth storing, use it to inform routing, and compare it
 460                                 //to the new HTLC max field in channel_update
 461                                 true
 462                         },
 463                         Err(ChainError::NotSupported) => {
 464                                 // Tentatively accept, potentially exposing us to DoS attacks
 465                                 false
 466                         },
 467                         Err(ChainError::NotWatched) => {
 468                                 return Err(LightningError{err: "Channel announced on an unknown chain", action: ErrorAction::IgnoreError});
 469                         },
 470                         Err(ChainError::UnknownTx) => {
 471                                 return Err(LightningError{err: "Channel announced without corresponding UTXO entry", action: ErrorAction::IgnoreError});
 472                         },
 473                 };
 474
 475                 let mut network_lock = self.network_map.write().unwrap();
 476                 let network = &mut *network_lock;
 477
 478                 let should_relay = msg.contents.excess_data.is_empty();
 479
 480                 let chan_info = ChannelInfo {
 481                                 features: msg.contents.features.clone(),
 482                                 one_to_two: DirectionalChannelInfo {
 483                                         src_node_id: msg.contents.node_id_1.clone(),
 484                                         last_update: 0,
 485                                         enabled: false,
 486                                         cltv_expiry_delta: u16::max_value(),
 487                                         htlc_minimum_msat: u64::max_value(),
 488                                         fee_base_msat: u32::max_value(),
 489                                         fee_proportional_millionths: u32::max_value(),
 490                                         last_update_message: None,
 491                                 },
 492                                 two_to_one: DirectionalChannelInfo {
 493                                         src_node_id: msg.contents.node_id_2.clone(),
 494                                         last_update: 0,
 495                                         enabled: false,
 496                                         cltv_expiry_delta: u16::max_value(),
 497                                         htlc_minimum_msat: u64::max_value(),
 498                                         fee_base_msat: u32::max_value(),
 499                                         fee_proportional_millionths: u32::max_value(),
 500                                         last_update_message: None,
 501                                 },
 502                                 announcement_message: if should_relay { Some(msg.clone()) } else { None },
 503                         };
 504
 505                 match network.channels.entry(NetworkMap::get_key(msg.contents.short_channel_id, msg.contents.chain_hash)) {
 506                         BtreeEntry::Occupied(mut entry) => {
 507                                 //TODO: because asking the blockchain if short_channel_id is valid is only optional
 508                                 //in the blockchain API, we need to handle it smartly here, though it's unclear
 509                                 //exactly how...
 510                                 if checked_utxo {
 511                                         // Either our UTXO provider is busted, there was a reorg, or the UTXO provider
 512                                         // only sometimes returns results. In any case remove the previous entry. Note
 513                                         // that the spec expects us to "blacklist" the node_ids involved, but we can't
 514                                         // do that because
 515                                         // a) we don't *require* a UTXO provider that always returns results.
 516                                         // b) we don't track UTXOs of channels we know about and remove them if they
 517                                         //    get reorg'd out.
 518                                         // c) it's unclear how to do so without exposing ourselves to massive DoS risk.
 519                                         Self::remove_channel_in_nodes(&mut network.nodes, &entry.get(), msg.contents.short_channel_id);
 520                                         *entry.get_mut() = chan_info;
 521                                 } else {
 522                                         return Err(LightningError{err: "Already have knowledge of channel", action: ErrorAction::IgnoreError})
 523                                 }
 524                         },
 525                         BtreeEntry::Vacant(entry) => {
 526                                 entry.insert(chan_info);
 527                         }
 528                 };
 529
 530                 macro_rules! add_channel_to_node {
 531                         ( $node_id: expr ) => {
 532                                 match network.nodes.entry($node_id) {
 533                                         BtreeEntry::Occupied(node_entry) => {
 534                                                 node_entry.into_mut().channels.push(NetworkMap::get_key(msg.contents.short_channel_id, msg.contents.chain_hash));
 535                                         },
 536                                         BtreeEntry::Vacant(node_entry) => {
 537                                                 node_entry.insert(NodeInfo {
 538                                                         channels: vec!(NetworkMap::get_key(msg.contents.short_channel_id, msg.contents.chain_hash)),
 539                                                         lowest_inbound_channel_fee_base_msat: u32::max_value(),
 540                                                         lowest_inbound_channel_fee_proportional_millionths: u32::max_value(),
 541                                                         features: NodeFeatures::empty(),
 542                                                         last_update: 0,
 543                                                         rgb: [0; 3],
 544                                                         alias: [0; 32],
 545                                                         addresses: Vec::new(),
 546                                                         announcement_message: None,
 547                                                 });
 548                                         }
 549                                 }
 550                         };
 551                 }
 552
 553                 add_channel_to_node!(msg.contents.node_id_1);
 554                 add_channel_to_node!(msg.contents.node_id_2);
 555
 556                 Ok(should_relay)
 557         }
 558
 559         fn handle_htlc_fail_channel_update(&self, update: &msgs::HTLCFailChannelUpdate) {
 560                 match update {
 561                         &msgs::HTLCFailChannelUpdate::ChannelUpdateMessage { ref msg } => {
 562                                 let _ = self.handle_channel_update(msg);
 563                         },
 564                         &msgs::HTLCFailChannelUpdate::ChannelClosed { ref short_channel_id, ref is_permanent } => {
 565                                 let mut network = self.network_map.write().unwrap();
 566                                 if *is_permanent {
 567                                         if let Some(chan) = network.channels.remove(short_channel_id) {
 568                                                 Self::remove_channel_in_nodes(&mut network.nodes, &chan, *short_channel_id);
 569                                         }
 570                                 } else {
 571                                         if let Some(chan) = network.channels.get_mut(short_channel_id) {
 572                                                 chan.one_to_two.enabled = false;
 573                                                 chan.two_to_one.enabled = false;
 574                                         }
 575                                 }
 576                         },
 577                         &msgs::HTLCFailChannelUpdate::NodeFailure { ref node_id, ref is_permanent } => {
 578                                 if *is_permanent {
 579                                         //TODO: Wholly remove the node
 580                                 } else {
 581                                         self.mark_node_bad(node_id, false);
 582                                 }
 583                         },
 584                 }
 585         }
 586
 587         fn handle_channel_update(&self, msg: &msgs::ChannelUpdate) -> Result<bool, LightningError> {
 588                 let mut network = self.network_map.write().unwrap();
 589                 let dest_node_id;
 590                 let chan_enabled = msg.contents.flags & (1 << 1) != (1 << 1);
 591                 let chan_was_enabled;
 592
 593                 match network.channels.get_mut(&NetworkMap::get_key(msg.contents.short_channel_id, msg.contents.chain_hash)) {
 594                         None => return Err(LightningError{err: "Couldn't find channel for update", action: ErrorAction::IgnoreError}),
 595                         Some(channel) => {
 596                                 macro_rules! maybe_update_channel_info {
 597                                         ( $target: expr) => {
 598                                                 if $target.last_update >= msg.contents.timestamp {
 599                                                         return Err(LightningError{err: "Update older than last processed update", action: ErrorAction::IgnoreError});
 600                                                 }
 601                                                 chan_was_enabled = $target.enabled;
 602                                                 $target.last_update = msg.contents.timestamp;
 603                                                 $target.enabled = chan_enabled;
 604                                                 $target.cltv_expiry_delta = msg.contents.cltv_expiry_delta;
 605                                                 $target.htlc_minimum_msat = msg.contents.htlc_minimum_msat;
 606                                                 $target.fee_base_msat = msg.contents.fee_base_msat;
 607                                                 $target.fee_proportional_millionths = msg.contents.fee_proportional_millionths;
 608                                                 $target.last_update_message = if msg.contents.excess_data.is_empty() {
 609                                                         Some(msg.clone())
 610                                                 } else {
 611                                                         None
 612                                                 };
 613                                         }
 614                                 }
 615                                 let msg_hash = hash_to_message!(&Sha256dHash::hash(&msg.contents.encode()[..])[..]);
 616                                 if msg.contents.flags & 1 == 1 {
 617                                         dest_node_id = channel.one_to_two.src_node_id.clone();
 618                                         secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.signature, &channel.two_to_one.src_node_id);
 619                                         maybe_update_channel_info!(channel.two_to_one);
 620                                 } else {
 621                                         dest_node_id = channel.two_to_one.src_node_id.clone();
 622                                         secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.signature, &channel.one_to_two.src_node_id);
 623                                         maybe_update_channel_info!(channel.one_to_two);
 624                                 }
 625                         }
 626                 }
 627
 628                 if chan_enabled {
 629                         let node = network.nodes.get_mut(&dest_node_id).unwrap();
 630                         node.lowest_inbound_channel_fee_base_msat = cmp::min(node.lowest_inbound_channel_fee_base_msat, msg.contents.fee_base_msat);
 631                         node.lowest_inbound_channel_fee_proportional_millionths = cmp::min(node.lowest_inbound_channel_fee_proportional_millionths, msg.contents.fee_proportional_millionths);
 632                 } else if chan_was_enabled {
 633                         let mut lowest_inbound_channel_fee_base_msat = u32::max_value();
 634                         let mut lowest_inbound_channel_fee_proportional_millionths = u32::max_value();
 635
 636                         {
 637                                 let node = network.nodes.get(&dest_node_id).unwrap();
 638
 639                                 for chan_id in node.channels.iter() {
 640                                         let chan = network.channels.get(chan_id).unwrap();
 641                                         if chan.one_to_two.src_node_id == dest_node_id {
 642                                                 lowest_inbound_channel_fee_base_msat = cmp::min(lowest_inbound_channel_fee_base_msat, chan.two_to_one.fee_base_msat);
 643                                                 lowest_inbound_channel_fee_proportional_millionths = cmp::min(lowest_inbound_channel_fee_proportional_millionths, chan.two_to_one.fee_proportional_millionths);
 644                                         } else {
 645                                                 lowest_inbound_channel_fee_base_msat = cmp::min(lowest_inbound_channel_fee_base_msat, chan.one_to_two.fee_base_msat);
 646                                                 lowest_inbound_channel_fee_proportional_millionths = cmp::min(lowest_inbound_channel_fee_proportional_millionths, chan.one_to_two.fee_proportional_millionths);
 647                                         }
 648                                 }
 649                         }
 650
 651                         //TODO: satisfy the borrow-checker without a double-map-lookup :(
 652                         let mut_node = network.nodes.get_mut(&dest_node_id).unwrap();
 653                         mut_node.lowest_inbound_channel_fee_base_msat = lowest_inbound_channel_fee_base_msat;
 654                         mut_node.lowest_inbound_channel_fee_proportional_millionths = lowest_inbound_channel_fee_proportional_millionths;
 655                 }
 656
 657                 Ok(msg.contents.excess_data.is_empty())
 658         }
 659
 660
 661         fn get_next_channel_announcements(&self, starting_point: u64, batch_amount: u8) -> Vec<(msgs::ChannelAnnouncement, msgs::ChannelUpdate,msgs::ChannelUpdate)> {
 662                 let mut result = Vec::with_capacity(batch_amount as usize);
 663                 let network = self.network_map.read().unwrap();
 664                 let mut iter = network.channels.range(starting_point..);
 665                 while result.len() < batch_amount as usize {
 666                         if let Some((_, ref chan)) = iter.next() {
 667                                 if chan.announcement_message.is_some() &&
 668                                                 chan.one_to_two.last_update_message.is_some() &&
 669                                                 chan.two_to_one.last_update_message.is_some() {
 670                                         result.push((chan.announcement_message.clone().unwrap(),
 671                                                 chan.one_to_two.last_update_message.clone().unwrap(),
 672                                                 chan.two_to_one.last_update_message.clone().unwrap()));
 673                                 } else {
 674                                         // TODO: We may end up sending un-announced channel_updates if we are sending
 675                                         // initial sync data while receiving announce/updates for this channel.
 676                                 }
 677                         } else {
 678                                 return result;
 679                         }
 680                 }
 681                 result
 682         }
 683
 684         fn get_next_node_announcements(&self, starting_point: Option<&PublicKey>, batch_amount: u8) -> Vec<msgs::NodeAnnouncement> {
 685                 let mut result = Vec::with_capacity(batch_amount as usize);
 686                 let network = self.network_map.read().unwrap();
 687                 let mut iter = if let Some(pubkey) = starting_point {
 688                                 let mut iter = network.nodes.range((*pubkey)..);
 689                                 iter.next();
 690                                 iter
 691                         } else {
 692                                 network.nodes.range(..)
 693                         };
 694                 while result.len() < batch_amount as usize {
 695                         if let Some((_, ref node)) = iter.next() {
 696                                 if node.announcement_message.is_some() {
 697                                         result.push(node.announcement_message.clone().unwrap());
 698                                 }
 699                         } else {
 700                                 return result;
 701                         }
 702                 }
 703                 result
 704         }
 705
 706         fn should_request_full_sync(&self, _node_id: &PublicKey) -> bool {
 707                 //TODO: Determine whether to request a full sync based on the network map.
 708                 const FULL_SYNCS_TO_REQUEST: usize = 5;
 709                 if self.full_syncs_requested.load(Ordering::Acquire) < FULL_SYNCS_TO_REQUEST {
 710                         self.full_syncs_requested.fetch_add(1, Ordering::AcqRel);
 711                         true
 712                 } else {
 713                         false
 714                 }
 715         }
 716 }
 717
 718 #[derive(Eq, PartialEq)]
 719 struct RouteGraphNode {
 720         pubkey: PublicKey,
 721         lowest_fee_to_peer_through_node: u64,
 722         lowest_fee_to_node: u64,
 723 }
 724
 725 impl cmp::Ord for RouteGraphNode {
 726         fn cmp(&self, other: &RouteGraphNode) -> cmp::Ordering {
 727                 other.lowest_fee_to_peer_through_node.cmp(&self.lowest_fee_to_peer_through_node)
 728                         .then_with(|| other.pubkey.serialize().cmp(&self.pubkey.serialize()))
 729         }
 730 }
 731
 732 impl cmp::PartialOrd for RouteGraphNode {
 733         fn partial_cmp(&self, other: &RouteGraphNode) -> Option<cmp::Ordering> {
 734                 Some(self.cmp(other))
 735         }
 736 }
 737
 738 struct DummyDirectionalChannelInfo {
 739         src_node_id: PublicKey,
 740         cltv_expiry_delta: u32,
 741         htlc_minimum_msat: u64,
 742         fee_base_msat: u32,
 743         fee_proportional_millionths: u32,
 744 }
 745
 746 impl Router {
 747         /// Creates a new router with the given node_id to be used as the source for get_route()
 748         pub fn new(our_pubkey: PublicKey, chain_monitor: Arc<ChainWatchInterface>, logger: Arc<Logger>) -> Router {
 749                 let mut nodes = BTreeMap::new();
 750                 nodes.insert(our_pubkey.clone(), NodeInfo {
 751                         channels: Vec::new(),
 752                         lowest_inbound_channel_fee_base_msat: u32::max_value(),
 753                         lowest_inbound_channel_fee_proportional_millionths: u32::max_value(),
 754                         features: NodeFeatures::empty(),
 755                         last_update: 0,
 756                         rgb: [0; 3],
 757                         alias: [0; 32],
 758                         addresses: Vec::new(),
 759                         announcement_message: None,
 760                 });
 761                 Router {
 762                         secp_ctx: Secp256k1::verification_only(),
 763                         network_map: RwLock::new(NetworkMap {
 764                                 channels: BTreeMap::new(),
 765                                 our_node_id: our_pubkey,
 766                                 nodes: nodes,
 767                         }),
 768                         full_syncs_requested: AtomicUsize::new(0),
 769                         chain_monitor,
 770                         logger,
 771                 }
 772         }
 773
 774         /// Dumps the entire network view of this Router to the logger provided in the constructor at
 775         /// level Trace
 776         pub fn trace_state(&self) {
 777                 log_trace!(self, "{}", self.network_map.read().unwrap());
 778         }
 779
 780         /// Get network addresses by node id
 781         pub fn get_addresses(&self, pubkey: &PublicKey) -> Option<Vec<NetAddress>> {
 782                 let network = self.network_map.read().unwrap();
 783                 network.nodes.get(pubkey).map(|n| n.addresses.clone())
 784         }
 785
 786         /// Marks a node as having failed a route. This will avoid re-using the node in routes for now,
 787         /// with an exponential decay in node "badness". Note that there is deliberately no
 788         /// mark_channel_bad as a node may simply lie and suggest that an upstream channel from it is
 789         /// what failed the route and not the node itself. Instead, setting the blamed_upstream_node
 790         /// boolean will reduce the penalty, returning the node to usability faster. If the node is
 791         /// behaving correctly, it will disable the failing channel and we will use it again next time.
 792         pub fn mark_node_bad(&self, _node_id: &PublicKey, _blamed_upstream_node: bool) {
 793                 unimplemented!();
 794         }
 795
 796         fn remove_channel_in_nodes(nodes: &mut BTreeMap<PublicKey, NodeInfo>, chan: &ChannelInfo, short_channel_id: u64) {
 797                 macro_rules! remove_from_node {
 798                         ($node_id: expr) => {
 799                                 if let BtreeEntry::Occupied(mut entry) = nodes.entry($node_id) {
 800                                         entry.get_mut().channels.retain(|chan_id| {
 801                                                 short_channel_id != *NetworkMap::get_short_id(chan_id)
 802                                         });
 803                                         if entry.get().channels.is_empty() {
 804                                                 entry.remove_entry();
 805                                         }
 806                                 } else {
 807                                         panic!("Had channel that pointed to unknown node (ie inconsistent network map)!");
 808                                 }
 809                         }
 810                 }
 811                 remove_from_node!(chan.one_to_two.src_node_id);
 812                 remove_from_node!(chan.two_to_one.src_node_id);
 813         }
 814
 815         /// Gets a route from us to the given target node.
 816         ///
 817         /// Extra routing hops between known nodes and the target will be used if they are included in
 818         /// last_hops.
 819         ///
 820         /// If some channels aren't announced, it may be useful to fill in a first_hops with the
 821         /// results from a local ChannelManager::list_usable_channels() call. If it is filled in, our
 822         /// (this Router's) view of our local channels will be ignored, and only those in first_hops
 823         /// will be used.
 824         ///
 825         /// Panics if first_hops contains channels without short_channel_ids
 826         /// (ChannelManager::list_usable_channels will never include such channels).
 827         ///
 828         /// The fees on channels from us to next-hops are ignored (as they are assumed to all be
 829         /// equal), however the enabled/disabled bit on such channels as well as the htlc_minimum_msat
 830         /// *is* checked as they may change based on the receiving node.
 831         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> {
 832                 // TODO: Obviously *only* using total fee cost sucks. We should consider weighting by
 833                 // uptime/success in using a node in the past.
 834                 let network = self.network_map.read().unwrap();
 835
 836                 if *target == network.our_node_id {
 837                         return Err(LightningError{err: "Cannot generate a route to ourselves", action: ErrorAction::IgnoreError});
 838                 }
 839
 840                 if final_value_msat > 21_000_000 * 1_0000_0000 * 1000 {
 841                         return Err(LightningError{err: "Cannot generate a route of more value than all existing satoshis", action: ErrorAction::IgnoreError});
 842                 }
 843
 844                 // We do a dest-to-source Dijkstra's sorting by each node's distance from the destination
 845                 // plus the minimum per-HTLC fee to get from it to another node (aka "shitty A*").
 846                 // TODO: There are a few tweaks we could do, including possibly pre-calculating more stuff
 847                 // to use as the A* heuristic beyond just the cost to get one node further than the current
 848                 // one.
 849
 850                 let dummy_directional_info = DummyDirectionalChannelInfo { // used for first_hops routes
 851                         src_node_id: network.our_node_id.clone(),
 852                         cltv_expiry_delta: 0,
 853                         htlc_minimum_msat: 0,
 854                         fee_base_msat: 0,
 855                         fee_proportional_millionths: 0,
 856                 };
 857
 858                 let mut targets = BinaryHeap::new(); //TODO: Do we care about switching to eg Fibbonaci heap?
 859                 let mut dist = HashMap::with_capacity(network.nodes.len());
 860
 861                 let mut first_hop_targets = HashMap::with_capacity(if first_hops.is_some() { first_hops.as_ref().unwrap().len() } else { 0 });
 862                 if let Some(hops) = first_hops {
 863                         for chan in hops {
 864                                 let short_channel_id = chan.short_channel_id.expect("first_hops should be filled in with usable channels, not pending ones");
 865                                 if chan.remote_network_id == *target {
 866                                         return Ok(Route {
 867                                                 hops: vec![RouteHop {
 868                                                         pubkey: chan.remote_network_id,
 869                                                         node_features: NodeFeatures::with_known_relevant_init_flags(&chan.counterparty_features),
 870                                                         short_channel_id,
 871                                                         channel_features: ChannelFeatures::with_known_relevant_init_flags(&chan.counterparty_features),
 872                                                         fee_msat: final_value_msat,
 873                                                         cltv_expiry_delta: final_cltv,
 874                                                 }],
 875                                         });
 876                                 }
 877                                 first_hop_targets.insert(chan.remote_network_id, (short_channel_id, chan.counterparty_features.clone()));
 878                         }
 879                         if first_hop_targets.is_empty() {
 880                                 return Err(LightningError{err: "Cannot route when there are no outbound routes away from us", action: ErrorAction::IgnoreError});
 881                         }
 882                 }
 883
 884                 macro_rules! add_entry {
 885                         // Adds entry which goes from the node pointed to by $directional_info to
 886                         // $dest_node_id over the channel with id $chan_id with fees described in
 887                         // $directional_info.
 888                         ( $chan_id: expr, $dest_node_id: expr, $directional_info: expr, $chan_features: expr, $starting_fee_msat: expr ) => {
 889                                 //TODO: Explore simply adding fee to hit htlc_minimum_msat
 890                                 if $starting_fee_msat as u64 + final_value_msat >= $directional_info.htlc_minimum_msat {
 891                                         let proportional_fee_millions = ($starting_fee_msat + final_value_msat).checked_mul($directional_info.fee_proportional_millionths as u64);
 892                                         if let Some(new_fee) = proportional_fee_millions.and_then(|part| {
 893                                                         ($directional_info.fee_base_msat as u64).checked_add(part / 1000000) })
 894                                         {
 895                                                 let mut total_fee = $starting_fee_msat as u64;
 896                                                 let hm_entry = dist.entry(&$directional_info.src_node_id);
 897                                                 let old_entry = hm_entry.or_insert_with(|| {
 898                                                         let node = network.nodes.get(&$directional_info.src_node_id).unwrap();
 899                                                         (u64::max_value(),
 900                                                                 node.lowest_inbound_channel_fee_base_msat,
 901                                                                 node.lowest_inbound_channel_fee_proportional_millionths,
 902                                                                 RouteHop {
 903                                                                         pubkey: $dest_node_id.clone(),
 904                                                                         node_features: NodeFeatures::empty(),
 905                                                                         short_channel_id: 0,
 906                                                                         channel_features: $chan_features.clone(),
 907                                                                         fee_msat: 0,
 908                                                                         cltv_expiry_delta: 0,
 909                                                         })
 910                                                 });
 911                                                 if $directional_info.src_node_id != network.our_node_id {
 912                                                         // Ignore new_fee for channel-from-us as we assume all channels-from-us
 913                                                         // will have the same effective-fee
 914                                                         total_fee += new_fee;
 915                                                         if let Some(fee_inc) = final_value_msat.checked_add(total_fee).and_then(|inc| { (old_entry.2 as u64).checked_mul(inc) }) {
 916                                                                 total_fee += fee_inc / 1000000 + (old_entry.1 as u64);
 917                                                         } else {
 918                                                                 // max_value means we'll always fail the old_entry.0 > total_fee check
 919                                                                 total_fee = u64::max_value();
 920                                                         }
 921                                                 }
 922                                                 let new_graph_node = RouteGraphNode {
 923                                                         pubkey: $directional_info.src_node_id,
 924                                                         lowest_fee_to_peer_through_node: total_fee,
 925                                                         lowest_fee_to_node: $starting_fee_msat as u64 + new_fee,
 926                                                 };
 927                                                 if old_entry.0 > total_fee {
 928                                                         targets.push(new_graph_node);
 929                                                         old_entry.0 = total_fee;
 930                                                         old_entry.3 = RouteHop {
 931                                                                 pubkey: $dest_node_id.clone(),
 932                                                                 node_features: NodeFeatures::empty(),
 933                                                                 short_channel_id: $chan_id.clone(),
 934                                                                 channel_features: $chan_features.clone(),
 935                                                                 fee_msat: new_fee, // This field is ignored on the last-hop anyway
 936                                                                 cltv_expiry_delta: $directional_info.cltv_expiry_delta as u32,
 937                                                         }
 938                                                 }
 939                                         }
 940                                 }
 941                         };
 942                 }
 943
 944                 macro_rules! add_entries_to_cheapest_to_target_node {
 945                         ( $node: expr, $node_id: expr, $fee_to_target_msat: expr ) => {
 946                                 if first_hops.is_some() {
 947                                         if let Some(&(ref first_hop, ref features)) = first_hop_targets.get(&$node_id) {
 948                                                 add_entry!(first_hop, $node_id, dummy_directional_info, ChannelFeatures::with_known_relevant_init_flags(&features), $fee_to_target_msat);
 949                                         }
 950                                 }
 951
 952                                 if !$node.features.requires_unknown_bits() {
 953                                         for chan_id in $node.channels.iter() {
 954                                                 let chan = network.channels.get(chan_id).unwrap();
 955                                                 if !chan.features.requires_unknown_bits() {
 956                                                         if chan.one_to_two.src_node_id == *$node_id {
 957                                                                 // ie $node is one, ie next hop in A* is two, via the two_to_one channel
 958                                                                 if first_hops.is_none() || chan.two_to_one.src_node_id != network.our_node_id {
 959                                                                         if chan.two_to_one.enabled {
 960                                                                                 add_entry!(chan_id, chan.one_to_two.src_node_id, chan.two_to_one, chan.features, $fee_to_target_msat);
 961                                                                         }
 962                                                                 }
 963                                                         } else {
 964                                                                 if first_hops.is_none() || chan.one_to_two.src_node_id != network.our_node_id {
 965                                                                         if chan.one_to_two.enabled {
 966                                                                                 add_entry!(chan_id, chan.two_to_one.src_node_id, chan.one_to_two, chan.features, $fee_to_target_msat);
 967                                                                         }
 968                                                                 }
 969                                                         }
 970                                                 }
 971                                         }
 972                                 }
 973                         };
 974                 }
 975
 976                 match network.nodes.get(target) {
 977                         None => {},
 978                         Some(node) => {
 979                                 add_entries_to_cheapest_to_target_node!(node, target, 0);
 980                         },
 981                 }
 982
 983                 for hop in last_hops.iter() {
 984                         if first_hops.is_none() || hop.src_node_id != network.our_node_id { // first_hop overrules last_hops
 985                                 if network.nodes.get(&hop.src_node_id).is_some() {
 986                                         if first_hops.is_some() {
 987                                                 if let Some(&(ref first_hop, ref features)) = first_hop_targets.get(&hop.src_node_id) {
 988                                                         // Currently there are no channel-context features defined, so we are a
 989                                                         // bit lazy here. In the future, we should pull them out via our
 990                                                         // ChannelManager, but there's no reason to waste the space until we
 991                                                         // need them.
 992                                                         add_entry!(first_hop, hop.src_node_id, dummy_directional_info, ChannelFeatures::with_known_relevant_init_flags(&features), 0);
 993                                                 }
 994                                         }
 995                                         // BOLT 11 doesn't allow inclusion of features for the last hop hints, which
 996                                         // really sucks, cause we're gonna need that eventually.
 997                                         add_entry!(hop.short_channel_id, target, hop, ChannelFeatures::empty(), 0);
 998                                 }
 999                         }
1000                 }
1001
1002                 while let Some(RouteGraphNode { pubkey, lowest_fee_to_node, .. }) = targets.pop() {
1003                         if pubkey == network.our_node_id {
1004                                 let mut res = vec!(dist.remove(&network.our_node_id).unwrap().3);
1005                                 loop {
1006                                         if let Some(&(_, ref features)) = first_hop_targets.get(&res.last().unwrap().pubkey) {
1007                                                 res.last_mut().unwrap().node_features = NodeFeatures::with_known_relevant_init_flags(&features);
1008                                         } else if let Some(node) = network.nodes.get(&res.last().unwrap().pubkey) {
1009                                                 res.last_mut().unwrap().node_features = node.features.clone();
1010                                         } else {
1011                                                 // We should be able to fill in features for everything except the last
1012                                                 // hop, if the last hop was provided via a BOLT 11 invoice (though we
1013                                                 // should be able to extend it further as BOLT 11 does have feature
1014                                                 // flags for the last hop node itself).
1015                                                 assert!(res.last().unwrap().pubkey == *target);
1016                                         }
1017                                         if res.last().unwrap().pubkey == *target {
1018                                                 break;
1019                                         }
1020
1021                                         let new_entry = match dist.remove(&res.last().unwrap().pubkey) {
1022                                                 Some(hop) => hop.3,
1023                                                 None => return Err(LightningError{err: "Failed to find a non-fee-overflowing path to the given destination", action: ErrorAction::IgnoreError}),
1024                                         };
1025                                         res.last_mut().unwrap().fee_msat = new_entry.fee_msat;
1026                                         res.last_mut().unwrap().cltv_expiry_delta = new_entry.cltv_expiry_delta;
1027                                         res.push(new_entry);
1028                                 }
1029                                 res.last_mut().unwrap().fee_msat = final_value_msat;
1030                                 res.last_mut().unwrap().cltv_expiry_delta = final_cltv;
1031                                 let route = Route { hops: res };
1032                                 log_trace!(self, "Got route: {}", log_route!(route));
1033                                 return Ok(route);
1034                         }
1035
1036                         match network.nodes.get(&pubkey) {
1037                                 None => {},
1038                                 Some(node) => {
1039                                         add_entries_to_cheapest_to_target_node!(node, &pubkey, lowest_fee_to_node);
1040                                 },
1041                         }
1042                 }
1043
1044                 Err(LightningError{err: "Failed to find a path to the given destination", action: ErrorAction::IgnoreError})
1045         }
1046 }
1047
1048 #[cfg(test)]
1049 mod tests {
1050         use chain::chaininterface;
1051         use ln::channelmanager;
1052         use ln::router::{Router,NodeInfo,NetworkMap,ChannelInfo,DirectionalChannelInfo,RouteHint};
1053         use ln::features::{ChannelFeatures, InitFeatures, NodeFeatures};
1054         use ln::msgs::{ErrorAction, LightningError, RoutingMessageHandler};
1055         use util::test_utils;
1056         use util::test_utils::TestVecWriter;
1057         use util::logger::Logger;
1058         use util::ser::{Writeable, Readable};
1059
1060         use bitcoin_hashes::sha256d::Hash as Sha256dHash;
1061         use bitcoin_hashes::Hash;
1062         use bitcoin::network::constants::Network;
1063
1064         use hex;
1065
1066         use secp256k1::key::{PublicKey,SecretKey};
1067         use secp256k1::All;
1068         use secp256k1::Secp256k1;
1069
1070         use std::sync::Arc;
1071
1072         fn create_router() -> (Secp256k1<All>, PublicKey, Router) {
1073                 let secp_ctx = Secp256k1::new();
1074                 let our_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap());
1075                 let logger: Arc<Logger> = Arc::new(test_utils::TestLogger::new());
1076                 let chain_monitor = Arc::new(chaininterface::ChainWatchInterfaceUtil::new(Network::Testnet, Arc::clone(&logger)));
1077                 let router = Router::new(our_id, chain_monitor, Arc::clone(&logger));
1078                 (secp_ctx, our_id, router)
1079         }
1080
1081         #[test]
1082         fn route_test() {
1083                 let (secp_ctx, our_id, router) = create_router();
1084
1085                 // Build network from our_id to node8:
1086                 //
1087                 //        -1(1)2-  node1  -1(3)2-
1088                 //       /                       \
1089                 // our_id -1(12)2- node8 -1(13)2--- node3
1090                 //       \                       /
1091                 //        -1(2)2-  node2  -1(4)2-
1092                 //
1093                 //
1094                 // chan1  1-to-2: disabled
1095                 // chan1  2-to-1: enabled, 0 fee
1096                 //
1097                 // chan2  1-to-2: enabled, ignored fee
1098                 // chan2  2-to-1: enabled, 0 fee
1099                 //
1100                 // chan3  1-to-2: enabled, 0 fee
1101                 // chan3  2-to-1: enabled, 100 msat fee
1102                 //
1103                 // chan4  1-to-2: enabled, 100% fee
1104                 // chan4  2-to-1: enabled, 0 fee
1105                 //
1106                 // chan12 1-to-2: enabled, ignored fee
1107                 // chan12 2-to-1: enabled, 0 fee
1108                 //
1109                 // chan13 1-to-2: enabled, 200% fee
1110                 // chan13 2-to-1: enabled, 0 fee
1111                 //
1112                 //
1113                 //       -1(5)2- node4 -1(8)2--
1114                 //       |         2          |
1115                 //       |       (11)         |
1116                 //      /          1           \
1117                 // node3--1(6)2- node5 -1(9)2--- node7 (not in global route map)
1118                 //      \                      /
1119                 //       -1(7)2- node6 -1(10)2-
1120                 //
1121                 // chan5  1-to-2: enabled, 100 msat fee
1122                 // chan5  2-to-1: enabled, 0 fee
1123                 //
1124                 // chan6  1-to-2: enabled, 0 fee
1125                 // chan6  2-to-1: enabled, 0 fee
1126                 //
1127                 // chan7  1-to-2: enabled, 100% fee
1128                 // chan7  2-to-1: enabled, 0 fee
1129                 //
1130                 // chan8  1-to-2: enabled, variable fee (0 then 1000 msat)
1131                 // chan8  2-to-1: enabled, 0 fee
1132                 //
1133                 // chan9  1-to-2: enabled, 1001 msat fee
1134                 // chan9  2-to-1: enabled, 0 fee
1135                 //
1136                 // chan10 1-to-2: enabled, 0 fee
1137                 // chan10 2-to-1: enabled, 0 fee
1138                 //
1139                 // chan11 1-to-2: enabled, 0 fee
1140                 // chan11 2-to-1: enabled, 0 fee
1141
1142                 let node1 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0202020202020202020202020202020202020202020202020202020202020202").unwrap()[..]).unwrap());
1143                 let node2 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0303030303030303030303030303030303030303030303030303030303030303").unwrap()[..]).unwrap());
1144                 let node3 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0404040404040404040404040404040404040404040404040404040404040404").unwrap()[..]).unwrap());
1145                 let node4 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0505050505050505050505050505050505050505050505050505050505050505").unwrap()[..]).unwrap());
1146                 let node5 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0606060606060606060606060606060606060606060606060606060606060606").unwrap()[..]).unwrap());
1147                 let node6 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0707070707070707070707070707070707070707070707070707070707070707").unwrap()[..]).unwrap());
1148                 let node7 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0808080808080808080808080808080808080808080808080808080808080808").unwrap()[..]).unwrap());
1149                 let node8 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0909090909090909090909090909090909090909090909090909090909090909").unwrap()[..]).unwrap());
1150
1151                 let zero_hash = Sha256dHash::hash(&[0; 32]);
1152
1153                 macro_rules! id_to_feature_flags {
1154                         // Set the feature flags to the id'th odd (ie non-required) feature bit so that we can
1155                         // test for it later.
1156                         ($id: expr) => { {
1157                                 let idx = ($id - 1) * 2 + 1;
1158                                 if idx > 8*3 {
1159                                         vec![1 << (idx - 8*3), 0, 0, 0]
1160                                 } else if idx > 8*2 {
1161                                         vec![1 << (idx - 8*2), 0, 0]
1162                                 } else if idx > 8*1 {
1163                                         vec![1 << (idx - 8*1), 0]
1164                                 } else {
1165                                         vec![1 << idx]
1166                                 }
1167                         } }
1168                 }
1169
1170                 {
1171                         let mut network = router.network_map.write().unwrap();
1172
1173                         network.nodes.insert(node1.clone(), NodeInfo {
1174                                 channels: vec!(NetworkMap::get_key(1, zero_hash.clone()), NetworkMap::get_key(3, zero_hash.clone())),
1175                                 lowest_inbound_channel_fee_base_msat: 100,
1176                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1177                                 features: NodeFeatures::from_le_bytes(id_to_feature_flags!(1)),
1178                                 last_update: 1,
1179                                 rgb: [0; 3],
1180                                 alias: [0; 32],
1181                                 addresses: Vec::new(),
1182                                 announcement_message: None,
1183                         });
1184                         network.channels.insert(NetworkMap::get_key(1, zero_hash.clone()), ChannelInfo {
1185                                 features: ChannelFeatures::from_le_bytes(id_to_feature_flags!(1)),
1186                                 one_to_two: DirectionalChannelInfo {
1187                                         src_node_id: our_id.clone(),
1188                                         last_update: 0,
1189                                         enabled: false,
1190                                         cltv_expiry_delta: u16::max_value(), // This value should be ignored
1191                                         htlc_minimum_msat: 0,
1192                                         fee_base_msat: u32::max_value(), // This value should be ignored
1193                                         fee_proportional_millionths: u32::max_value(), // This value should be ignored
1194                                         last_update_message: None,
1195                                 }, two_to_one: DirectionalChannelInfo {
1196                                         src_node_id: node1.clone(),
1197                                         last_update: 0,
1198                                         enabled: true,
1199                                         cltv_expiry_delta: 0,
1200                                         htlc_minimum_msat: 0,
1201                                         fee_base_msat: 0,
1202                                         fee_proportional_millionths: 0,
1203                                         last_update_message: None,
1204                                 },
1205                                 announcement_message: None,
1206                         });
1207                         network.nodes.insert(node2.clone(), NodeInfo {
1208                                 channels: vec!(NetworkMap::get_key(2, zero_hash.clone()), NetworkMap::get_key(4, zero_hash.clone())),
1209                                 lowest_inbound_channel_fee_base_msat: 0,
1210                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1211                                 features: NodeFeatures::from_le_bytes(id_to_feature_flags!(2)),
1212                                 last_update: 1,
1213                                 rgb: [0; 3],
1214                                 alias: [0; 32],
1215                                 addresses: Vec::new(),
1216                                 announcement_message: None,
1217                         });
1218                         network.channels.insert(NetworkMap::get_key(2, zero_hash.clone()), ChannelInfo {
1219                                 features: ChannelFeatures::from_le_bytes(id_to_feature_flags!(2)),
1220                                 one_to_two: DirectionalChannelInfo {
1221                                         src_node_id: our_id.clone(),
1222                                         last_update: 0,
1223                                         enabled: true,
1224                                         cltv_expiry_delta: u16::max_value(), // This value should be ignored
1225                                         htlc_minimum_msat: 0,
1226                                         fee_base_msat: u32::max_value(), // This value should be ignored
1227                                         fee_proportional_millionths: u32::max_value(), // This value should be ignored
1228                                         last_update_message: None,
1229                                 }, two_to_one: DirectionalChannelInfo {
1230                                         src_node_id: node2.clone(),
1231                                         last_update: 0,
1232                                         enabled: true,
1233                                         cltv_expiry_delta: 0,
1234                                         htlc_minimum_msat: 0,
1235                                         fee_base_msat: 0,
1236                                         fee_proportional_millionths: 0,
1237                                         last_update_message: None,
1238                                 },
1239                                 announcement_message: None,
1240                         });
1241                         network.nodes.insert(node8.clone(), NodeInfo {
1242                                 channels: vec!(NetworkMap::get_key(12, zero_hash.clone()), NetworkMap::get_key(13, zero_hash.clone())),
1243                                 lowest_inbound_channel_fee_base_msat: 0,
1244                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1245                                 features: NodeFeatures::from_le_bytes(id_to_feature_flags!(8)),
1246                                 last_update: 1,
1247                                 rgb: [0; 3],
1248                                 alias: [0; 32],
1249                                 addresses: Vec::new(),
1250                                 announcement_message: None,
1251                         });
1252                         network.channels.insert(NetworkMap::get_key(12, zero_hash.clone()), ChannelInfo {
1253                                 features: ChannelFeatures::from_le_bytes(id_to_feature_flags!(12)),
1254                                 one_to_two: DirectionalChannelInfo {
1255                                         src_node_id: our_id.clone(),
1256                                         last_update: 0,
1257                                         enabled: true,
1258                                         cltv_expiry_delta: u16::max_value(), // This value should be ignored
1259                                         htlc_minimum_msat: 0,
1260                                         fee_base_msat: u32::max_value(), // This value should be ignored
1261                                         fee_proportional_millionths: u32::max_value(), // This value should be ignored
1262                                         last_update_message: None,
1263                                 }, two_to_one: DirectionalChannelInfo {
1264                                         src_node_id: node8.clone(),
1265                                         last_update: 0,
1266                                         enabled: true,
1267                                         cltv_expiry_delta: 0,
1268                                         htlc_minimum_msat: 0,
1269                                         fee_base_msat: 0,
1270                                         fee_proportional_millionths: 0,
1271                                         last_update_message: None,
1272                                 },
1273                                 announcement_message: None,
1274                         });
1275                         network.nodes.insert(node3.clone(), NodeInfo {
1276                                 channels: vec!(
1277                                         NetworkMap::get_key(3, zero_hash.clone()),
1278                                         NetworkMap::get_key(4, zero_hash.clone()),
1279                                         NetworkMap::get_key(13, zero_hash.clone()),
1280                                         NetworkMap::get_key(5, zero_hash.clone()),
1281                                         NetworkMap::get_key(6, zero_hash.clone()),
1282                                         NetworkMap::get_key(7, zero_hash.clone())),
1283                                 lowest_inbound_channel_fee_base_msat: 0,
1284                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1285                                 features: NodeFeatures::from_le_bytes(id_to_feature_flags!(3)),
1286                                 last_update: 1,
1287                                 rgb: [0; 3],
1288                                 alias: [0; 32],
1289                                 addresses: Vec::new(),
1290                                 announcement_message: None,
1291                         });
1292                         network.channels.insert(NetworkMap::get_key(3, zero_hash.clone()), ChannelInfo {
1293                                 features: ChannelFeatures::from_le_bytes(id_to_feature_flags!(3)),
1294                                 one_to_two: DirectionalChannelInfo {
1295                                         src_node_id: node1.clone(),
1296                                         last_update: 0,
1297                                         enabled: true,
1298                                         cltv_expiry_delta: (3 << 8) | 1,
1299                                         htlc_minimum_msat: 0,
1300                                         fee_base_msat: 0,
1301                                         fee_proportional_millionths: 0,
1302                                         last_update_message: None,
1303                                 }, two_to_one: DirectionalChannelInfo {
1304                                         src_node_id: node3.clone(),
1305                                         last_update: 0,
1306                                         enabled: true,
1307                                         cltv_expiry_delta: (3 << 8) | 2,
1308                                         htlc_minimum_msat: 0,
1309                                         fee_base_msat: 100,
1310                                         fee_proportional_millionths: 0,
1311                                         last_update_message: None,
1312                                 },
1313                                 announcement_message: None,
1314                         });
1315                         network.channels.insert(NetworkMap::get_key(4, zero_hash.clone()), ChannelInfo {
1316                                 features: ChannelFeatures::from_le_bytes(id_to_feature_flags!(4)),
1317                                 one_to_two: DirectionalChannelInfo {
1318                                         src_node_id: node2.clone(),
1319                                         last_update: 0,
1320                                         enabled: true,
1321                                         cltv_expiry_delta: (4 << 8) | 1,
1322                                         htlc_minimum_msat: 0,
1323                                         fee_base_msat: 0,
1324                                         fee_proportional_millionths: 1000000,
1325                                         last_update_message: None,
1326                                 }, two_to_one: DirectionalChannelInfo {
1327                                         src_node_id: node3.clone(),
1328                                         last_update: 0,
1329                                         enabled: true,
1330                                         cltv_expiry_delta: (4 << 8) | 2,
1331                                         htlc_minimum_msat: 0,
1332                                         fee_base_msat: 0,
1333                                         fee_proportional_millionths: 0,
1334                                         last_update_message: None,
1335                                 },
1336                                 announcement_message: None,
1337                         });
1338                         network.channels.insert(NetworkMap::get_key(13, zero_hash.clone()), ChannelInfo {
1339                                 features: ChannelFeatures::from_le_bytes(id_to_feature_flags!(13)),
1340                                 one_to_two: DirectionalChannelInfo {
1341                                         src_node_id: node8.clone(),
1342                                         last_update: 0,
1343                                         enabled: true,
1344                                         cltv_expiry_delta: (13 << 8) | 1,
1345                                         htlc_minimum_msat: 0,
1346                                         fee_base_msat: 0,
1347                                         fee_proportional_millionths: 2000000,
1348                                         last_update_message: None,
1349                                 }, two_to_one: DirectionalChannelInfo {
1350                                         src_node_id: node3.clone(),
1351                                         last_update: 0,
1352                                         enabled: true,
1353                                         cltv_expiry_delta: (13 << 8) | 2,
1354                                         htlc_minimum_msat: 0,
1355                                         fee_base_msat: 0,
1356                                         fee_proportional_millionths: 0,
1357                                         last_update_message: None,
1358                                 },
1359                                 announcement_message: None,
1360                         });
1361                         network.nodes.insert(node4.clone(), NodeInfo {
1362                                 channels: vec!(NetworkMap::get_key(5, zero_hash.clone()), NetworkMap::get_key(11, zero_hash.clone())),
1363                                 lowest_inbound_channel_fee_base_msat: 0,
1364                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1365                                 features: NodeFeatures::from_le_bytes(id_to_feature_flags!(4)),
1366                                 last_update: 1,
1367                                 rgb: [0; 3],
1368                                 alias: [0; 32],
1369                                 addresses: Vec::new(),
1370                                 announcement_message: None,
1371                         });
1372                         network.channels.insert(NetworkMap::get_key(5, zero_hash.clone()), ChannelInfo {
1373                                 features: ChannelFeatures::from_le_bytes(id_to_feature_flags!(5)),
1374                                 one_to_two: DirectionalChannelInfo {
1375                                         src_node_id: node3.clone(),
1376                                         last_update: 0,
1377                                         enabled: true,
1378                                         cltv_expiry_delta: (5 << 8) | 1,
1379                                         htlc_minimum_msat: 0,
1380                                         fee_base_msat: 100,
1381                                         fee_proportional_millionths: 0,
1382                                         last_update_message: None,
1383                                 }, two_to_one: DirectionalChannelInfo {
1384                                         src_node_id: node4.clone(),
1385                                         last_update: 0,
1386                                         enabled: true,
1387                                         cltv_expiry_delta: (5 << 8) | 2,
1388                                         htlc_minimum_msat: 0,
1389                                         fee_base_msat: 0,
1390                                         fee_proportional_millionths: 0,
1391                                         last_update_message: None,
1392                                 },
1393                                 announcement_message: None,
1394                         });
1395                         network.nodes.insert(node5.clone(), NodeInfo {
1396                                 channels: vec!(NetworkMap::get_key(6, zero_hash.clone()), NetworkMap::get_key(11, zero_hash.clone())),
1397                                 lowest_inbound_channel_fee_base_msat: 0,
1398                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1399                                 features: NodeFeatures::from_le_bytes(id_to_feature_flags!(5)),
1400                                 last_update: 1,
1401                                 rgb: [0; 3],
1402                                 alias: [0; 32],
1403                                 addresses: Vec::new(),
1404                                 announcement_message: None,
1405                         });
1406                         network.channels.insert(NetworkMap::get_key(6, zero_hash.clone()), ChannelInfo {
1407                                 features: ChannelFeatures::from_le_bytes(id_to_feature_flags!(6)),
1408                                 one_to_two: DirectionalChannelInfo {
1409                                         src_node_id: node3.clone(),
1410                                         last_update: 0,
1411                                         enabled: true,
1412                                         cltv_expiry_delta: (6 << 8) | 1,
1413                                         htlc_minimum_msat: 0,
1414                                         fee_base_msat: 0,
1415                                         fee_proportional_millionths: 0,
1416                                         last_update_message: None,
1417                                 }, two_to_one: DirectionalChannelInfo {
1418                                         src_node_id: node5.clone(),
1419                                         last_update: 0,
1420                                         enabled: true,
1421                                         cltv_expiry_delta: (6 << 8) | 2,
1422                                         htlc_minimum_msat: 0,
1423                                         fee_base_msat: 0,
1424                                         fee_proportional_millionths: 0,
1425                                         last_update_message: None,
1426                                 },
1427                                 announcement_message: None,
1428                         });
1429                         network.channels.insert(NetworkMap::get_key(11, zero_hash.clone()), ChannelInfo {
1430                                 features: ChannelFeatures::from_le_bytes(id_to_feature_flags!(11)),
1431                                 one_to_two: DirectionalChannelInfo {
1432                                         src_node_id: node5.clone(),
1433                                         last_update: 0,
1434                                         enabled: true,
1435                                         cltv_expiry_delta: (11 << 8) | 1,
1436                                         htlc_minimum_msat: 0,
1437                                         fee_base_msat: 0,
1438                                         fee_proportional_millionths: 0,
1439                                         last_update_message: None,
1440                                 }, two_to_one: DirectionalChannelInfo {
1441                                         src_node_id: node4.clone(),
1442                                         last_update: 0,
1443                                         enabled: true,
1444                                         cltv_expiry_delta: (11 << 8) | 2,
1445                                         htlc_minimum_msat: 0,
1446                                         fee_base_msat: 0,
1447                                         fee_proportional_millionths: 0,
1448                                         last_update_message: None,
1449                                 },
1450                                 announcement_message: None,
1451                         });
1452                         network.nodes.insert(node6.clone(), NodeInfo {
1453                                 channels: vec!(NetworkMap::get_key(7, zero_hash.clone())),
1454                                 lowest_inbound_channel_fee_base_msat: 0,
1455                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1456                                 features: NodeFeatures::from_le_bytes(id_to_feature_flags!(6)),
1457                                 last_update: 1,
1458                                 rgb: [0; 3],
1459                                 alias: [0; 32],
1460                                 addresses: Vec::new(),
1461                                 announcement_message: None,
1462                         });
1463                         network.channels.insert(NetworkMap::get_key(7, zero_hash.clone()), ChannelInfo {
1464                                 features: ChannelFeatures::from_le_bytes(id_to_feature_flags!(7)),
1465                                 one_to_two: DirectionalChannelInfo {
1466                                         src_node_id: node3.clone(),
1467                                         last_update: 0,
1468                                         enabled: true,
1469                                         cltv_expiry_delta: (7 << 8) | 1,
1470                                         htlc_minimum_msat: 0,
1471                                         fee_base_msat: 0,
1472                                         fee_proportional_millionths: 1000000,
1473                                         last_update_message: None,
1474                                 }, two_to_one: DirectionalChannelInfo {
1475                                         src_node_id: node6.clone(),
1476                                         last_update: 0,
1477                                         enabled: true,
1478                                         cltv_expiry_delta: (7 << 8) | 2,
1479                                         htlc_minimum_msat: 0,
1480                                         fee_base_msat: 0,
1481                                         fee_proportional_millionths: 0,
1482                                         last_update_message: None,
1483                                 },
1484                                 announcement_message: None,
1485                         });
1486                 }
1487
1488                 { // Simple route to 3 via 2
1489                         let route = router.get_route(&node3, None, &Vec::new(), 100, 42).unwrap();
1490                         assert_eq!(route.hops.len(), 2);
1491
1492                         assert_eq!(route.hops[0].pubkey, node2);
1493                         assert_eq!(route.hops[0].short_channel_id, 2);
1494                         assert_eq!(route.hops[0].fee_msat, 100);
1495                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1496                         assert_eq!(route.hops[0].node_features.le_flags(), &id_to_feature_flags!(2));
1497                         assert_eq!(route.hops[0].channel_features.le_flags(), &id_to_feature_flags!(2));
1498
1499                         assert_eq!(route.hops[1].pubkey, node3);
1500                         assert_eq!(route.hops[1].short_channel_id, 4);
1501                         assert_eq!(route.hops[1].fee_msat, 100);
1502                         assert_eq!(route.hops[1].cltv_expiry_delta, 42);
1503                         assert_eq!(route.hops[1].node_features.le_flags(), &id_to_feature_flags!(3));
1504                         assert_eq!(route.hops[1].channel_features.le_flags(), &id_to_feature_flags!(4));
1505                 }
1506
1507                 { // Disable channels 4 and 12 by requiring unknown feature bits
1508                         let mut network = router.network_map.write().unwrap();
1509                         network.channels.get_mut(&NetworkMap::get_key(4, zero_hash.clone())).unwrap().features.set_require_unknown_bits();
1510                         network.channels.get_mut(&NetworkMap::get_key(12, zero_hash.clone())).unwrap().features.set_require_unknown_bits();
1511                 }
1512
1513                 { // If all the channels require some features we don't understand, route should fail
1514                         if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = router.get_route(&node3, None, &Vec::new(), 100, 42) {
1515                                 assert_eq!(err, "Failed to find a path to the given destination");
1516                         } else { panic!(); }
1517                 }
1518
1519                 { // If we specify a channel to node8, that overrides our local channel view and that gets used
1520                         let our_chans = vec![channelmanager::ChannelDetails {
1521                                 channel_id: [0; 32],
1522                                 short_channel_id: Some(42),
1523                                 remote_network_id: node8.clone(),
1524                                 counterparty_features: InitFeatures::from_le_bytes(vec![0b11]),
1525                                 channel_value_satoshis: 0,
1526                                 user_id: 0,
1527                                 outbound_capacity_msat: 0,
1528                                 inbound_capacity_msat: 0,
1529                                 is_live: true,
1530                         }];
1531                         let route = router.get_route(&node3, Some(&our_chans), &Vec::new(), 100, 42).unwrap();
1532                         assert_eq!(route.hops.len(), 2);
1533
1534                         assert_eq!(route.hops[0].pubkey, node8);
1535                         assert_eq!(route.hops[0].short_channel_id, 42);
1536                         assert_eq!(route.hops[0].fee_msat, 200);
1537                         assert_eq!(route.hops[0].cltv_expiry_delta, (13 << 8) | 1);
1538                         assert_eq!(route.hops[0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
1539                         assert_eq!(route.hops[0].channel_features.le_flags(), &Vec::new()); // No feature flags will meet the relevant-to-channel conversion
1540
1541                         assert_eq!(route.hops[1].pubkey, node3);
1542                         assert_eq!(route.hops[1].short_channel_id, 13);
1543                         assert_eq!(route.hops[1].fee_msat, 100);
1544                         assert_eq!(route.hops[1].cltv_expiry_delta, 42);
1545                         assert_eq!(route.hops[1].node_features.le_flags(), &id_to_feature_flags!(3));
1546                         assert_eq!(route.hops[1].channel_features.le_flags(), &id_to_feature_flags!(13));
1547                 }
1548
1549                 { // Re-enable channels 4 and 12 by wiping the unknown feature bits
1550                         let mut network = router.network_map.write().unwrap();
1551                         network.channels.get_mut(&NetworkMap::get_key(4, zero_hash.clone())).unwrap().features.clear_require_unknown_bits();
1552                         network.channels.get_mut(&NetworkMap::get_key(12, zero_hash.clone())).unwrap().features.clear_require_unknown_bits();
1553                 }
1554
1555                 { // Disable nodes 1, 2, and 8 by requiring unknown feature bits
1556                         let mut network = router.network_map.write().unwrap();
1557                         network.nodes.get_mut(&node1).unwrap().features.set_require_unknown_bits();
1558                         network.nodes.get_mut(&node2).unwrap().features.set_require_unknown_bits();
1559                         network.nodes.get_mut(&node8).unwrap().features.set_require_unknown_bits();
1560                 }
1561
1562                 { // If all nodes require some features we don't understand, route should fail
1563                         if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = router.get_route(&node3, None, &Vec::new(), 100, 42) {
1564                                 assert_eq!(err, "Failed to find a path to the given destination");
1565                         } else { panic!(); }
1566                 }
1567
1568                 { // If we specify a channel to node8, that overrides our local channel view and that gets used
1569                         let our_chans = vec![channelmanager::ChannelDetails {
1570                                 channel_id: [0; 32],
1571                                 short_channel_id: Some(42),
1572                                 remote_network_id: node8.clone(),
1573                                 counterparty_features: InitFeatures::from_le_bytes(vec![0b11]),
1574                                 channel_value_satoshis: 0,
1575                                 user_id: 0,
1576                                 outbound_capacity_msat: 0,
1577                                 inbound_capacity_msat: 0,
1578                                 is_live: true,
1579                         }];
1580                         let route = router.get_route(&node3, Some(&our_chans), &Vec::new(), 100, 42).unwrap();
1581                         assert_eq!(route.hops.len(), 2);
1582
1583                         assert_eq!(route.hops[0].pubkey, node8);
1584                         assert_eq!(route.hops[0].short_channel_id, 42);
1585                         assert_eq!(route.hops[0].fee_msat, 200);
1586                         assert_eq!(route.hops[0].cltv_expiry_delta, (13 << 8) | 1);
1587                         assert_eq!(route.hops[0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
1588                         assert_eq!(route.hops[0].channel_features.le_flags(), &Vec::new()); // No feature flags will meet the relevant-to-channel conversion
1589
1590                         assert_eq!(route.hops[1].pubkey, node3);
1591                         assert_eq!(route.hops[1].short_channel_id, 13);
1592                         assert_eq!(route.hops[1].fee_msat, 100);
1593                         assert_eq!(route.hops[1].cltv_expiry_delta, 42);
1594                         assert_eq!(route.hops[1].node_features.le_flags(), &id_to_feature_flags!(3));
1595                         assert_eq!(route.hops[1].channel_features.le_flags(), &id_to_feature_flags!(13));
1596                 }
1597
1598                 { // Re-enable nodes 1, 2, and 8
1599                         let mut network = router.network_map.write().unwrap();
1600                         network.nodes.get_mut(&node1).unwrap().features.clear_require_unknown_bits();
1601                         network.nodes.get_mut(&node2).unwrap().features.clear_require_unknown_bits();
1602                         network.nodes.get_mut(&node8).unwrap().features.clear_require_unknown_bits();
1603                 }
1604
1605                 // Note that we don't test disabling node 3 and failing to route to it, as we (somewhat
1606                 // naively) assume that the user checked the feature bits on the invoice, which override
1607                 // the node_announcement.
1608
1609                 { // Route to 1 via 2 and 3 because our channel to 1 is disabled
1610                         let route = router.get_route(&node1, None, &Vec::new(), 100, 42).unwrap();
1611                         assert_eq!(route.hops.len(), 3);
1612
1613                         assert_eq!(route.hops[0].pubkey, node2);
1614                         assert_eq!(route.hops[0].short_channel_id, 2);
1615                         assert_eq!(route.hops[0].fee_msat, 200);
1616                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1617                         assert_eq!(route.hops[0].node_features.le_flags(), &id_to_feature_flags!(2));
1618                         assert_eq!(route.hops[0].channel_features.le_flags(), &id_to_feature_flags!(2));
1619
1620                         assert_eq!(route.hops[1].pubkey, node3);
1621                         assert_eq!(route.hops[1].short_channel_id, 4);
1622                         assert_eq!(route.hops[1].fee_msat, 100);
1623                         assert_eq!(route.hops[1].cltv_expiry_delta, (3 << 8) | 2);
1624                         assert_eq!(route.hops[1].node_features.le_flags(), &id_to_feature_flags!(3));
1625                         assert_eq!(route.hops[1].channel_features.le_flags(), &id_to_feature_flags!(4));
1626
1627                         assert_eq!(route.hops[2].pubkey, node1);
1628                         assert_eq!(route.hops[2].short_channel_id, 3);
1629                         assert_eq!(route.hops[2].fee_msat, 100);
1630                         assert_eq!(route.hops[2].cltv_expiry_delta, 42);
1631                         assert_eq!(route.hops[2].node_features.le_flags(), &id_to_feature_flags!(1));
1632                         assert_eq!(route.hops[2].channel_features.le_flags(), &id_to_feature_flags!(3));
1633                 }
1634
1635                 { // If we specify a channel to node8, that overrides our local channel view and that gets used
1636                         let our_chans = vec![channelmanager::ChannelDetails {
1637                                 channel_id: [0; 32],
1638                                 short_channel_id: Some(42),
1639                                 remote_network_id: node8.clone(),
1640                                 counterparty_features: InitFeatures::from_le_bytes(vec![0b11]),
1641                                 channel_value_satoshis: 0,
1642                                 user_id: 0,
1643                                 outbound_capacity_msat: 0,
1644                                 inbound_capacity_msat: 0,
1645                                 is_live: true,
1646                         }];
1647                         let route = router.get_route(&node3, Some(&our_chans), &Vec::new(), 100, 42).unwrap();
1648                         assert_eq!(route.hops.len(), 2);
1649
1650                         assert_eq!(route.hops[0].pubkey, node8);
1651                         assert_eq!(route.hops[0].short_channel_id, 42);
1652                         assert_eq!(route.hops[0].fee_msat, 200);
1653                         assert_eq!(route.hops[0].cltv_expiry_delta, (13 << 8) | 1);
1654                         assert_eq!(route.hops[0].node_features.le_flags(), &vec![0b11]);
1655                         assert_eq!(route.hops[0].channel_features.le_flags(), &Vec::new()); // No feature flags will meet the relevant-to-channel conversion
1656
1657                         assert_eq!(route.hops[1].pubkey, node3);
1658                         assert_eq!(route.hops[1].short_channel_id, 13);
1659                         assert_eq!(route.hops[1].fee_msat, 100);
1660                         assert_eq!(route.hops[1].cltv_expiry_delta, 42);
1661                         assert_eq!(route.hops[1].node_features.le_flags(), &id_to_feature_flags!(3));
1662                         assert_eq!(route.hops[1].channel_features.le_flags(), &id_to_feature_flags!(13));
1663                 }
1664
1665                 let mut last_hops = vec!(RouteHint {
1666                                 src_node_id: node4.clone(),
1667                                 short_channel_id: 8,
1668                                 fee_base_msat: 0,
1669                                 fee_proportional_millionths: 0,
1670                                 cltv_expiry_delta: (8 << 8) | 1,
1671                                 htlc_minimum_msat: 0,
1672                         }, RouteHint {
1673                                 src_node_id: node5.clone(),
1674                                 short_channel_id: 9,
1675                                 fee_base_msat: 1001,
1676                                 fee_proportional_millionths: 0,
1677                                 cltv_expiry_delta: (9 << 8) | 1,
1678                                 htlc_minimum_msat: 0,
1679                         }, RouteHint {
1680                                 src_node_id: node6.clone(),
1681                                 short_channel_id: 10,
1682                                 fee_base_msat: 0,
1683                                 fee_proportional_millionths: 0,
1684                                 cltv_expiry_delta: (10 << 8) | 1,
1685                                 htlc_minimum_msat: 0,
1686                         });
1687
1688                 { // Simple test across 2, 3, 5, and 4 via a last_hop channel
1689                         let route = router.get_route(&node7, None, &last_hops, 100, 42).unwrap();
1690                         assert_eq!(route.hops.len(), 5);
1691
1692                         assert_eq!(route.hops[0].pubkey, node2);
1693                         assert_eq!(route.hops[0].short_channel_id, 2);
1694                         assert_eq!(route.hops[0].fee_msat, 100);
1695                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1696                         assert_eq!(route.hops[0].node_features.le_flags(), &id_to_feature_flags!(2));
1697                         assert_eq!(route.hops[0].channel_features.le_flags(), &id_to_feature_flags!(2));
1698
1699                         assert_eq!(route.hops[1].pubkey, node3);
1700                         assert_eq!(route.hops[1].short_channel_id, 4);
1701                         assert_eq!(route.hops[1].fee_msat, 0);
1702                         assert_eq!(route.hops[1].cltv_expiry_delta, (6 << 8) | 1);
1703                         assert_eq!(route.hops[1].node_features.le_flags(), &id_to_feature_flags!(3));
1704                         assert_eq!(route.hops[1].channel_features.le_flags(), &id_to_feature_flags!(4));
1705
1706                         assert_eq!(route.hops[2].pubkey, node5);
1707                         assert_eq!(route.hops[2].short_channel_id, 6);
1708                         assert_eq!(route.hops[2].fee_msat, 0);
1709                         assert_eq!(route.hops[2].cltv_expiry_delta, (11 << 8) | 1);
1710                         assert_eq!(route.hops[2].node_features.le_flags(), &id_to_feature_flags!(5));
1711                         assert_eq!(route.hops[2].channel_features.le_flags(), &id_to_feature_flags!(6));
1712
1713                         assert_eq!(route.hops[3].pubkey, node4);
1714                         assert_eq!(route.hops[3].short_channel_id, 11);
1715                         assert_eq!(route.hops[3].fee_msat, 0);
1716                         assert_eq!(route.hops[3].cltv_expiry_delta, (8 << 8) | 1);
1717                         // If we have a peer in the node map, we'll use their features here since we don't have
1718                         // a way of figuring out their features from the invoice:
1719                         assert_eq!(route.hops[3].node_features.le_flags(), &id_to_feature_flags!(4));
1720                         assert_eq!(route.hops[3].channel_features.le_flags(), &id_to_feature_flags!(11));
1721
1722                         assert_eq!(route.hops[4].pubkey, node7);
1723                         assert_eq!(route.hops[4].short_channel_id, 8);
1724                         assert_eq!(route.hops[4].fee_msat, 100);
1725                         assert_eq!(route.hops[4].cltv_expiry_delta, 42);
1726                         assert_eq!(route.hops[4].node_features.le_flags(), &Vec::new()); // We dont pass flags in from invoices yet
1727                         assert_eq!(route.hops[4].channel_features.le_flags(), &Vec::new()); // We can't learn any flags from invoices, sadly
1728                 }
1729
1730                 { // Simple test with outbound channel to 4 to test that last_hops and first_hops connect
1731                         let our_chans = vec![channelmanager::ChannelDetails {
1732                                 channel_id: [0; 32],
1733                                 short_channel_id: Some(42),
1734                                 remote_network_id: node4.clone(),
1735                                 counterparty_features: InitFeatures::from_le_bytes(vec![0b11]),
1736                                 channel_value_satoshis: 0,
1737                                 user_id: 0,
1738                                 outbound_capacity_msat: 0,
1739                                 inbound_capacity_msat: 0,
1740                                 is_live: true,
1741                         }];
1742                         let route = router.get_route(&node7, Some(&our_chans), &last_hops, 100, 42).unwrap();
1743                         assert_eq!(route.hops.len(), 2);
1744
1745                         assert_eq!(route.hops[0].pubkey, node4);
1746                         assert_eq!(route.hops[0].short_channel_id, 42);
1747                         assert_eq!(route.hops[0].fee_msat, 0);
1748                         assert_eq!(route.hops[0].cltv_expiry_delta, (8 << 8) | 1);
1749                         assert_eq!(route.hops[0].node_features.le_flags(), &vec![0b11]);
1750                         assert_eq!(route.hops[0].channel_features.le_flags(), &Vec::new()); // No feature flags will meet the relevant-to-channel conversion
1751
1752                         assert_eq!(route.hops[1].pubkey, node7);
1753                         assert_eq!(route.hops[1].short_channel_id, 8);
1754                         assert_eq!(route.hops[1].fee_msat, 100);
1755                         assert_eq!(route.hops[1].cltv_expiry_delta, 42);
1756                         assert_eq!(route.hops[1].node_features.le_flags(), &Vec::new()); // We dont pass flags in from invoices yet
1757                         assert_eq!(route.hops[1].channel_features.le_flags(), &Vec::new()); // We can't learn any flags from invoices, sadly
1758                 }
1759
1760                 last_hops[0].fee_base_msat = 1000;
1761
1762                 { // Revert to via 6 as the fee on 8 goes up
1763                         let route = router.get_route(&node7, None, &last_hops, 100, 42).unwrap();
1764                         assert_eq!(route.hops.len(), 4);
1765
1766                         assert_eq!(route.hops[0].pubkey, node2);
1767                         assert_eq!(route.hops[0].short_channel_id, 2);
1768                         assert_eq!(route.hops[0].fee_msat, 200); // fee increased as its % of value transferred across node
1769                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1770                         assert_eq!(route.hops[0].node_features.le_flags(), &id_to_feature_flags!(2));
1771                         assert_eq!(route.hops[0].channel_features.le_flags(), &id_to_feature_flags!(2));
1772
1773                         assert_eq!(route.hops[1].pubkey, node3);
1774                         assert_eq!(route.hops[1].short_channel_id, 4);
1775                         assert_eq!(route.hops[1].fee_msat, 100);
1776                         assert_eq!(route.hops[1].cltv_expiry_delta, (7 << 8) | 1);
1777                         assert_eq!(route.hops[1].node_features.le_flags(), &id_to_feature_flags!(3));
1778                         assert_eq!(route.hops[1].channel_features.le_flags(), &id_to_feature_flags!(4));
1779
1780                         assert_eq!(route.hops[2].pubkey, node6);
1781                         assert_eq!(route.hops[2].short_channel_id, 7);
1782                         assert_eq!(route.hops[2].fee_msat, 0);
1783                         assert_eq!(route.hops[2].cltv_expiry_delta, (10 << 8) | 1);
1784                         // If we have a peer in the node map, we'll use their features here since we don't have
1785                         // a way of figuring out their features from the invoice:
1786                         assert_eq!(route.hops[2].node_features.le_flags(), &id_to_feature_flags!(6));
1787                         assert_eq!(route.hops[2].channel_features.le_flags(), &id_to_feature_flags!(7));
1788
1789                         assert_eq!(route.hops[3].pubkey, node7);
1790                         assert_eq!(route.hops[3].short_channel_id, 10);
1791                         assert_eq!(route.hops[3].fee_msat, 100);
1792                         assert_eq!(route.hops[3].cltv_expiry_delta, 42);
1793                         assert_eq!(route.hops[3].node_features.le_flags(), &Vec::new()); // We dont pass flags in from invoices yet
1794                         assert_eq!(route.hops[3].channel_features.le_flags(), &Vec::new()); // We can't learn any flags from invoices, sadly
1795                 }
1796
1797                 { // ...but still use 8 for larger payments as 6 has a variable feerate
1798                         let route = router.get_route(&node7, None, &last_hops, 2000, 42).unwrap();
1799                         assert_eq!(route.hops.len(), 5);
1800
1801                         assert_eq!(route.hops[0].pubkey, node2);
1802                         assert_eq!(route.hops[0].short_channel_id, 2);
1803                         assert_eq!(route.hops[0].fee_msat, 3000);
1804                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1805                         assert_eq!(route.hops[0].node_features.le_flags(), &id_to_feature_flags!(2));
1806                         assert_eq!(route.hops[0].channel_features.le_flags(), &id_to_feature_flags!(2));
1807
1808                         assert_eq!(route.hops[1].pubkey, node3);
1809                         assert_eq!(route.hops[1].short_channel_id, 4);
1810                         assert_eq!(route.hops[1].fee_msat, 0);
1811                         assert_eq!(route.hops[1].cltv_expiry_delta, (6 << 8) | 1);
1812                         assert_eq!(route.hops[1].node_features.le_flags(), &id_to_feature_flags!(3));
1813                         assert_eq!(route.hops[1].channel_features.le_flags(), &id_to_feature_flags!(4));
1814
1815                         assert_eq!(route.hops[2].pubkey, node5);
1816                         assert_eq!(route.hops[2].short_channel_id, 6);
1817                         assert_eq!(route.hops[2].fee_msat, 0);
1818                         assert_eq!(route.hops[2].cltv_expiry_delta, (11 << 8) | 1);
1819                         assert_eq!(route.hops[2].node_features.le_flags(), &id_to_feature_flags!(5));
1820                         assert_eq!(route.hops[2].channel_features.le_flags(), &id_to_feature_flags!(6));
1821
1822                         assert_eq!(route.hops[3].pubkey, node4);
1823                         assert_eq!(route.hops[3].short_channel_id, 11);
1824                         assert_eq!(route.hops[3].fee_msat, 1000);
1825                         assert_eq!(route.hops[3].cltv_expiry_delta, (8 << 8) | 1);
1826                         // If we have a peer in the node map, we'll use their features here since we don't have
1827                         // a way of figuring out their features from the invoice:
1828                         assert_eq!(route.hops[3].node_features.le_flags(), &id_to_feature_flags!(4));
1829                         assert_eq!(route.hops[3].channel_features.le_flags(), &id_to_feature_flags!(11));
1830
1831                         assert_eq!(route.hops[4].pubkey, node7);
1832                         assert_eq!(route.hops[4].short_channel_id, 8);
1833                         assert_eq!(route.hops[4].fee_msat, 2000);
1834                         assert_eq!(route.hops[4].cltv_expiry_delta, 42);
1835                         assert_eq!(route.hops[4].node_features.le_flags(), &Vec::new()); // We dont pass flags in from invoices yet
1836                         assert_eq!(route.hops[4].channel_features.le_flags(), &Vec::new()); // We can't learn any flags from invoices, sadly
1837                 }
1838
1839                 { // Test Router serialization/deserialization
1840                         let mut w = TestVecWriter(Vec::new());
1841                         let network = router.network_map.read().unwrap();
1842                         assert!(!network.channels.is_empty());
1843                         assert!(!network.nodes.is_empty());
1844                         network.write(&mut w).unwrap();
1845                         assert!(<NetworkMap>::read(&mut ::std::io::Cursor::new(&w.0)).unwrap() == *network);
1846                 }
1847         }
1848
1849         #[test]
1850         fn request_full_sync_finite_times() {
1851                 let (secp_ctx, _, router) = create_router();
1852                 let node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0202020202020202020202020202020202020202020202020202020202020202").unwrap()[..]).unwrap());
1853
1854                 assert!(router.should_request_full_sync(&node_id));
1855                 assert!(router.should_request_full_sync(&node_id));
1856                 assert!(router.should_request_full_sync(&node_id));
1857                 assert!(router.should_request_full_sync(&node_id));
1858                 assert!(router.should_request_full_sync(&node_id));
1859                 assert!(!router.should_request_full_sync(&node_id));
1860         }
1861 }