_ 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 Readable for Route {
  75         fn read<R: ::std::io::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         /// Unlike for channels, we may have a NodeInfo entry before having received a node_update.
 160         /// Thus, we have to be able to capture "no update has been received", which we do with an
 161         /// Option here.
 162         last_update: Option<u32>,
 163         rgb: [u8; 3],
 164         alias: [u8; 32],
 165         addresses: Vec<NetAddress>,
 166         //this is cached here so we can send out it later if required by route_init_sync
 167         //keep an eye on this to see if the extra memory is a problem
 168         announcement_message: Option<msgs::NodeAnnouncement>,
 169 }
 170
 171 impl std::fmt::Display for NodeInfo {
 172         fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
 173                 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[..])?;
 174                 Ok(())
 175         }
 176 }
 177
 178 impl Writeable for NodeInfo {
 179         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 180                 (self.channels.len() as u64).write(writer)?;
 181                 for ref chan in self.channels.iter() {
 182                         chan.write(writer)?;
 183                 }
 184                 self.lowest_inbound_channel_fee_base_msat.write(writer)?;
 185                 self.lowest_inbound_channel_fee_proportional_millionths.write(writer)?;
 186                 self.features.write(writer)?;
 187                 self.last_update.write(writer)?;
 188                 self.rgb.write(writer)?;
 189                 self.alias.write(writer)?;
 190                 (self.addresses.len() as u64).write(writer)?;
 191                 for ref addr in &self.addresses {
 192                         addr.write(writer)?;
 193                 }
 194                 self.announcement_message.write(writer)?;
 195                 Ok(())
 196         }
 197 }
 198
 199 const MAX_ALLOC_SIZE: u64 = 64*1024;
 200
 201 impl Readable for NodeInfo {
 202         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<NodeInfo, DecodeError> {
 203                 let channels_count: u64 = Readable::read(reader)?;
 204                 let mut channels = Vec::with_capacity(cmp::min(channels_count, MAX_ALLOC_SIZE / 8) as usize);
 205                 for _ in 0..channels_count {
 206                         channels.push(Readable::read(reader)?);
 207                 }
 208                 let lowest_inbound_channel_fee_base_msat = Readable::read(reader)?;
 209                 let lowest_inbound_channel_fee_proportional_millionths = Readable::read(reader)?;
 210                 let features = Readable::read(reader)?;
 211                 let last_update = Readable::read(reader)?;
 212                 let rgb = Readable::read(reader)?;
 213                 let alias = Readable::read(reader)?;
 214                 let addresses_count: u64 = Readable::read(reader)?;
 215                 let mut addresses = Vec::with_capacity(cmp::min(addresses_count, MAX_ALLOC_SIZE / 40) as usize);
 216                 for _ in 0..addresses_count {
 217                         match Readable::read(reader) {
 218                                 Ok(Ok(addr)) => { addresses.push(addr); },
 219                                 Ok(Err(_)) => return Err(DecodeError::InvalidValue),
 220                                 Err(DecodeError::ShortRead) => return Err(DecodeError::BadLengthDescriptor),
 221                                 _ => unreachable!(),
 222                         }
 223                 }
 224                 let announcement_message = Readable::read(reader)?;
 225                 Ok(NodeInfo {
 226                         channels,
 227                         lowest_inbound_channel_fee_base_msat,
 228                         lowest_inbound_channel_fee_proportional_millionths,
 229                         features,
 230                         last_update,
 231                         rgb,
 232                         alias,
 233                         addresses,
 234                         announcement_message
 235                 })
 236         }
 237 }
 238
 239 #[derive(PartialEq)]
 240 struct NetworkMap {
 241         #[cfg(feature = "non_bitcoin_chain_hash_routing")]
 242         channels: BTreeMap<(u64, Sha256dHash), ChannelInfo>,
 243         #[cfg(not(feature = "non_bitcoin_chain_hash_routing"))]
 244         channels: BTreeMap<u64, ChannelInfo>,
 245
 246         our_node_id: PublicKey,
 247         nodes: BTreeMap<PublicKey, NodeInfo>,
 248 }
 249
 250 impl Writeable for NetworkMap {
 251         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 252                 (self.channels.len() as u64).write(writer)?;
 253                 for (ref chan_id, ref chan_info) in self.channels.iter() {
 254                         (*chan_id).write(writer)?;
 255                         chan_info.write(writer)?;
 256                 }
 257                 self.our_node_id.write(writer)?;
 258                 (self.nodes.len() as u64).write(writer)?;
 259                 for (ref node_id, ref node_info) in self.nodes.iter() {
 260                         node_id.write(writer)?;
 261                         node_info.write(writer)?;
 262                 }
 263                 Ok(())
 264         }
 265 }
 266
 267 impl Readable for NetworkMap {
 268         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<NetworkMap, DecodeError> {
 269                 let channels_count: u64 = Readable::read(reader)?;
 270                 let mut channels = BTreeMap::new();
 271                 for _ in 0..channels_count {
 272                         let chan_id: u64 = Readable::read(reader)?;
 273                         let chan_info = Readable::read(reader)?;
 274                         channels.insert(chan_id, chan_info);
 275                 }
 276                 let our_node_id = Readable::read(reader)?;
 277                 let nodes_count: u64 = Readable::read(reader)?;
 278                 let mut nodes = BTreeMap::new();
 279                 for _ in 0..nodes_count {
 280                         let node_id = Readable::read(reader)?;
 281                         let node_info = Readable::read(reader)?;
 282                         nodes.insert(node_id, node_info);
 283                 }
 284                 Ok(NetworkMap {
 285                         channels,
 286                         our_node_id,
 287                         nodes,
 288                 })
 289         }
 290 }
 291
 292 impl std::fmt::Display for NetworkMap {
 293         fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
 294                 write!(f, "Node id {} network map\n[Channels]\n", log_pubkey!(self.our_node_id))?;
 295                 for (key, val) in self.channels.iter() {
 296                         write!(f, " {}: {}\n", key, val)?;
 297                 }
 298                 write!(f, "[Nodes]\n")?;
 299                 for (key, val) in self.nodes.iter() {
 300                         write!(f, " {}: {}\n", log_pubkey!(key), val)?;
 301                 }
 302                 Ok(())
 303         }
 304 }
 305
 306 impl NetworkMap {
 307         #[cfg(feature = "non_bitcoin_chain_hash_routing")]
 308         #[inline]
 309         fn get_key(short_channel_id: u64, chain_hash: Sha256dHash) -> (u64, Sha256dHash) {
 310                 (short_channel_id, chain_hash)
 311         }
 312
 313         #[cfg(not(feature = "non_bitcoin_chain_hash_routing"))]
 314         #[inline]
 315         fn get_key(short_channel_id: u64, _: Sha256dHash) -> u64 {
 316                 short_channel_id
 317         }
 318
 319         #[cfg(feature = "non_bitcoin_chain_hash_routing")]
 320         #[inline]
 321         fn get_short_id(id: &(u64, Sha256dHash)) -> &u64 {
 322                 &id.0
 323         }
 324
 325         #[cfg(not(feature = "non_bitcoin_chain_hash_routing"))]
 326         #[inline]
 327         fn get_short_id(id: &u64) -> &u64 {
 328                 id
 329         }
 330 }
 331
 332 /// A channel descriptor which provides a last-hop route to get_route
 333 pub struct RouteHint {
 334         /// The node_id of the non-target end of the route
 335         pub src_node_id: PublicKey,
 336         /// The short_channel_id of this channel
 337         pub short_channel_id: u64,
 338         /// The static msat-denominated fee which must be paid to use this channel
 339         pub fee_base_msat: u32,
 340         /// The dynamic proportional fee which must be paid to use this channel, denominated in
 341         /// millionths of the value being forwarded to the next hop.
 342         pub fee_proportional_millionths: u32,
 343         /// The difference in CLTV values between this node and the next node.
 344         pub cltv_expiry_delta: u16,
 345         /// The minimum value, in msat, which must be relayed to the next hop.
 346         pub htlc_minimum_msat: u64,
 347 }
 348
 349 /// Tracks a view of the network, receiving updates from peers and generating Routes to
 350 /// payment destinations.
 351 pub struct Router {
 352         secp_ctx: Secp256k1<secp256k1::VerifyOnly>,
 353         network_map: RwLock<NetworkMap>,
 354         full_syncs_requested: AtomicUsize,
 355         chain_monitor: Arc<ChainWatchInterface>,
 356         logger: Arc<Logger>,
 357 }
 358
 359 const SERIALIZATION_VERSION: u8 = 1;
 360 const MIN_SERIALIZATION_VERSION: u8 = 1;
 361
 362 impl Writeable for Router {
 363         fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
 364                 writer.write_all(&[SERIALIZATION_VERSION; 1])?;
 365                 writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
 366
 367                 let network = self.network_map.read().unwrap();
 368                 network.write(writer)?;
 369                 Ok(())
 370         }
 371 }
 372
 373 /// Arguments for the creation of a Router that are not deserialized.
 374 /// At a high-level, the process for deserializing a Router and resuming normal operation is:
 375 /// 1) Deserialize the Router by filling in this struct and calling <Router>::read(reaser, args).
 376 /// 2) Register the new Router with your ChainWatchInterface
 377 pub struct RouterReadArgs {
 378         /// The ChainWatchInterface for use in the Router in the future.
 379         ///
 380         /// No calls to the ChainWatchInterface will be made during deserialization.
 381         pub chain_monitor: Arc<ChainWatchInterface>,
 382         /// The Logger for use in the ChannelManager and which may be used to log information during
 383         /// deserialization.
 384         pub logger: Arc<Logger>,
 385 }
 386
 387 impl ReadableArgs<RouterReadArgs> for Router {
 388         fn read<R: ::std::io::Read>(reader: &mut R, args: RouterReadArgs) -> Result<Router, DecodeError> {
 389                 let _ver: u8 = Readable::read(reader)?;
 390                 let min_ver: u8 = Readable::read(reader)?;
 391                 if min_ver > SERIALIZATION_VERSION {
 392                         return Err(DecodeError::UnknownVersion);
 393                 }
 394                 let network_map = Readable::read(reader)?;
 395                 Ok(Router {
 396                         secp_ctx: Secp256k1::verification_only(),
 397                         network_map: RwLock::new(network_map),
 398                         full_syncs_requested: AtomicUsize::new(0),
 399                         chain_monitor: args.chain_monitor,
 400                         logger: args.logger,
 401                 })
 402         }
 403 }
 404
 405 macro_rules! secp_verify_sig {
 406         ( $secp_ctx: expr, $msg: expr, $sig: expr, $pubkey: expr ) => {
 407                 match $secp_ctx.verify($msg, $sig, $pubkey) {
 408                         Ok(_) => {},
 409                         Err(_) => return Err(LightningError{err: "Invalid signature from remote node", action: ErrorAction::IgnoreError}),
 410                 }
 411         };
 412 }
 413
 414 impl RoutingMessageHandler for Router {
 415
 416         fn handle_node_announcement(&self, msg: &msgs::NodeAnnouncement) -> Result<bool, LightningError> {
 417                 let msg_hash = hash_to_message!(&Sha256dHash::hash(&msg.contents.encode()[..])[..]);
 418                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.signature, &msg.contents.node_id);
 419
 420                 let mut network = self.network_map.write().unwrap();
 421                 match network.nodes.get_mut(&msg.contents.node_id) {
 422                         None => Err(LightningError{err: "No existing channels for node_announcement", action: ErrorAction::IgnoreError}),
 423                         Some(node) => {
 424                                 match node.last_update {
 425                                         Some(last_update) => if last_update >= msg.contents.timestamp {
 426                                                 return Err(LightningError{err: "Update older than last processed update", action: ErrorAction::IgnoreError});
 427                                         },
 428                                         None => {},
 429                                 }
 430
 431                                 node.features = msg.contents.features.clone();
 432                                 node.last_update = Some(msg.contents.timestamp);
 433                                 node.rgb = msg.contents.rgb;
 434                                 node.alias = msg.contents.alias;
 435                                 node.addresses = msg.contents.addresses.clone();
 436
 437                                 let should_relay = msg.contents.excess_data.is_empty() && msg.contents.excess_address_data.is_empty();
 438                                 node.announcement_message = if should_relay { Some(msg.clone()) } else { None };
 439                                 Ok(should_relay)
 440                         }
 441                 }
 442         }
 443
 444         fn handle_channel_announcement(&self, msg: &msgs::ChannelAnnouncement) -> Result<bool, LightningError> {
 445                 if msg.contents.node_id_1 == msg.contents.node_id_2 || msg.contents.bitcoin_key_1 == msg.contents.bitcoin_key_2 {
 446                         return Err(LightningError{err: "Channel announcement node had a channel with itself", action: ErrorAction::IgnoreError});
 447                 }
 448
 449                 let msg_hash = hash_to_message!(&Sha256dHash::hash(&msg.contents.encode()[..])[..]);
 450                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.node_signature_1, &msg.contents.node_id_1);
 451                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.node_signature_2, &msg.contents.node_id_2);
 452                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.bitcoin_signature_1, &msg.contents.bitcoin_key_1);
 453                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.bitcoin_signature_2, &msg.contents.bitcoin_key_2);
 454
 455                 let checked_utxo = match self.chain_monitor.get_chain_utxo(msg.contents.chain_hash, msg.contents.short_channel_id) {
 456                         Ok((script_pubkey, _value)) => {
 457                                 let expected_script = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
 458                                                                     .push_slice(&msg.contents.bitcoin_key_1.serialize())
 459                                                                     .push_slice(&msg.contents.bitcoin_key_2.serialize())
 460                                                                     .push_opcode(opcodes::all::OP_PUSHNUM_2)
 461                                                                     .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
 462                                 if script_pubkey != expected_script {
 463                                         return Err(LightningError{err: "Channel announcement keys didn't match on-chain script", action: ErrorAction::IgnoreError});
 464                                 }
 465                                 //TODO: Check if value is worth storing, use it to inform routing, and compare it
 466                                 //to the new HTLC max field in channel_update
 467                                 true
 468                         },
 469                         Err(ChainError::NotSupported) => {
 470                                 // Tentatively accept, potentially exposing us to DoS attacks
 471                                 false
 472                         },
 473                         Err(ChainError::NotWatched) => {
 474                                 return Err(LightningError{err: "Channel announced on an unknown chain", action: ErrorAction::IgnoreError});
 475                         },
 476                         Err(ChainError::UnknownTx) => {
 477                                 return Err(LightningError{err: "Channel announced without corresponding UTXO entry", action: ErrorAction::IgnoreError});
 478                         },
 479                 };
 480
 481                 let mut network_lock = self.network_map.write().unwrap();
 482                 let network = &mut *network_lock;
 483
 484                 let should_relay = msg.contents.excess_data.is_empty();
 485
 486                 let chan_info = ChannelInfo {
 487                                 features: msg.contents.features.clone(),
 488                                 one_to_two: DirectionalChannelInfo {
 489                                         src_node_id: msg.contents.node_id_1.clone(),
 490                                         last_update: 0,
 491                                         enabled: false,
 492                                         cltv_expiry_delta: u16::max_value(),
 493                                         htlc_minimum_msat: u64::max_value(),
 494                                         fee_base_msat: u32::max_value(),
 495                                         fee_proportional_millionths: u32::max_value(),
 496                                         last_update_message: None,
 497                                 },
 498                                 two_to_one: DirectionalChannelInfo {
 499                                         src_node_id: msg.contents.node_id_2.clone(),
 500                                         last_update: 0,
 501                                         enabled: false,
 502                                         cltv_expiry_delta: u16::max_value(),
 503                                         htlc_minimum_msat: u64::max_value(),
 504                                         fee_base_msat: u32::max_value(),
 505                                         fee_proportional_millionths: u32::max_value(),
 506                                         last_update_message: None,
 507                                 },
 508                                 announcement_message: if should_relay { Some(msg.clone()) } else { None },
 509                         };
 510
 511                 match network.channels.entry(NetworkMap::get_key(msg.contents.short_channel_id, msg.contents.chain_hash)) {
 512                         BtreeEntry::Occupied(mut entry) => {
 513                                 //TODO: because asking the blockchain if short_channel_id is valid is only optional
 514                                 //in the blockchain API, we need to handle it smartly here, though it's unclear
 515                                 //exactly how...
 516                                 if checked_utxo {
 517                                         // Either our UTXO provider is busted, there was a reorg, or the UTXO provider
 518                                         // only sometimes returns results. In any case remove the previous entry. Note
 519                                         // that the spec expects us to "blacklist" the node_ids involved, but we can't
 520                                         // do that because
 521                                         // a) we don't *require* a UTXO provider that always returns results.
 522                                         // b) we don't track UTXOs of channels we know about and remove them if they
 523                                         //    get reorg'd out.
 524                                         // c) it's unclear how to do so without exposing ourselves to massive DoS risk.
 525                                         Self::remove_channel_in_nodes(&mut network.nodes, &entry.get(), msg.contents.short_channel_id);
 526                                         *entry.get_mut() = chan_info;
 527                                 } else {
 528                                         return Err(LightningError{err: "Already have knowledge of channel", action: ErrorAction::IgnoreError})
 529                                 }
 530                         },
 531                         BtreeEntry::Vacant(entry) => {
 532                                 entry.insert(chan_info);
 533                         }
 534                 };
 535
 536                 macro_rules! add_channel_to_node {
 537                         ( $node_id: expr ) => {
 538                                 match network.nodes.entry($node_id) {
 539                                         BtreeEntry::Occupied(node_entry) => {
 540                                                 node_entry.into_mut().channels.push(NetworkMap::get_key(msg.contents.short_channel_id, msg.contents.chain_hash));
 541                                         },
 542                                         BtreeEntry::Vacant(node_entry) => {
 543                                                 node_entry.insert(NodeInfo {
 544                                                         channels: vec!(NetworkMap::get_key(msg.contents.short_channel_id, msg.contents.chain_hash)),
 545                                                         lowest_inbound_channel_fee_base_msat: u32::max_value(),
 546                                                         lowest_inbound_channel_fee_proportional_millionths: u32::max_value(),
 547                                                         features: NodeFeatures::empty(),
 548                                                         last_update: None,
 549                                                         rgb: [0; 3],
 550                                                         alias: [0; 32],
 551                                                         addresses: Vec::new(),
 552                                                         announcement_message: None,
 553                                                 });
 554                                         }
 555                                 }
 556                         };
 557                 }
 558
 559                 add_channel_to_node!(msg.contents.node_id_1);
 560                 add_channel_to_node!(msg.contents.node_id_2);
 561
 562                 Ok(should_relay)
 563         }
 564
 565         fn handle_htlc_fail_channel_update(&self, update: &msgs::HTLCFailChannelUpdate) {
 566                 match update {
 567                         &msgs::HTLCFailChannelUpdate::ChannelUpdateMessage { ref msg } => {
 568                                 let _ = self.handle_channel_update(msg);
 569                         },
 570                         &msgs::HTLCFailChannelUpdate::ChannelClosed { ref short_channel_id, ref is_permanent } => {
 571                                 let mut network = self.network_map.write().unwrap();
 572                                 if *is_permanent {
 573                                         if let Some(chan) = network.channels.remove(short_channel_id) {
 574                                                 Self::remove_channel_in_nodes(&mut network.nodes, &chan, *short_channel_id);
 575                                         }
 576                                 } else {
 577                                         if let Some(chan) = network.channels.get_mut(short_channel_id) {
 578                                                 chan.one_to_two.enabled = false;
 579                                                 chan.two_to_one.enabled = false;
 580                                         }
 581                                 }
 582                         },
 583                         &msgs::HTLCFailChannelUpdate::NodeFailure { ref node_id, ref is_permanent } => {
 584                                 if *is_permanent {
 585                                         //TODO: Wholly remove the node
 586                                 } else {
 587                                         self.mark_node_bad(node_id, false);
 588                                 }
 589                         },
 590                 }
 591         }
 592
 593         fn handle_channel_update(&self, msg: &msgs::ChannelUpdate) -> Result<bool, LightningError> {
 594                 let mut network = self.network_map.write().unwrap();
 595                 let dest_node_id;
 596                 let chan_enabled = msg.contents.flags & (1 << 1) != (1 << 1);
 597                 let chan_was_enabled;
 598
 599                 match network.channels.get_mut(&NetworkMap::get_key(msg.contents.short_channel_id, msg.contents.chain_hash)) {
 600                         None => return Err(LightningError{err: "Couldn't find channel for update", action: ErrorAction::IgnoreError}),
 601                         Some(channel) => {
 602                                 macro_rules! maybe_update_channel_info {
 603                                         ( $target: expr) => {
 604                                                 if $target.last_update >= msg.contents.timestamp {
 605                                                         return Err(LightningError{err: "Update older than last processed update", action: ErrorAction::IgnoreError});
 606                                                 }
 607                                                 chan_was_enabled = $target.enabled;
 608                                                 $target.last_update = msg.contents.timestamp;
 609                                                 $target.enabled = chan_enabled;
 610                                                 $target.cltv_expiry_delta = msg.contents.cltv_expiry_delta;
 611                                                 $target.htlc_minimum_msat = msg.contents.htlc_minimum_msat;
 612                                                 $target.fee_base_msat = msg.contents.fee_base_msat;
 613                                                 $target.fee_proportional_millionths = msg.contents.fee_proportional_millionths;
 614                                                 $target.last_update_message = if msg.contents.excess_data.is_empty() {
 615                                                         Some(msg.clone())
 616                                                 } else {
 617                                                         None
 618                                                 };
 619                                         }
 620                                 }
 621                                 let msg_hash = hash_to_message!(&Sha256dHash::hash(&msg.contents.encode()[..])[..]);
 622                                 if msg.contents.flags & 1 == 1 {
 623                                         dest_node_id = channel.one_to_two.src_node_id.clone();
 624                                         secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.signature, &channel.two_to_one.src_node_id);
 625                                         maybe_update_channel_info!(channel.two_to_one);
 626                                 } else {
 627                                         dest_node_id = channel.two_to_one.src_node_id.clone();
 628                                         secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.signature, &channel.one_to_two.src_node_id);
 629                                         maybe_update_channel_info!(channel.one_to_two);
 630                                 }
 631                         }
 632                 }
 633
 634                 if chan_enabled {
 635                         let node = network.nodes.get_mut(&dest_node_id).unwrap();
 636                         node.lowest_inbound_channel_fee_base_msat = cmp::min(node.lowest_inbound_channel_fee_base_msat, msg.contents.fee_base_msat);
 637                         node.lowest_inbound_channel_fee_proportional_millionths = cmp::min(node.lowest_inbound_channel_fee_proportional_millionths, msg.contents.fee_proportional_millionths);
 638                 } else if chan_was_enabled {
 639                         let mut lowest_inbound_channel_fee_base_msat = u32::max_value();
 640                         let mut lowest_inbound_channel_fee_proportional_millionths = u32::max_value();
 641
 642                         {
 643                                 let node = network.nodes.get(&dest_node_id).unwrap();
 644
 645                                 for chan_id in node.channels.iter() {
 646                                         let chan = network.channels.get(chan_id).unwrap();
 647                                         if chan.one_to_two.src_node_id == dest_node_id {
 648                                                 lowest_inbound_channel_fee_base_msat = cmp::min(lowest_inbound_channel_fee_base_msat, chan.two_to_one.fee_base_msat);
 649                                                 lowest_inbound_channel_fee_proportional_millionths = cmp::min(lowest_inbound_channel_fee_proportional_millionths, chan.two_to_one.fee_proportional_millionths);
 650                                         } else {
 651                                                 lowest_inbound_channel_fee_base_msat = cmp::min(lowest_inbound_channel_fee_base_msat, chan.one_to_two.fee_base_msat);
 652                                                 lowest_inbound_channel_fee_proportional_millionths = cmp::min(lowest_inbound_channel_fee_proportional_millionths, chan.one_to_two.fee_proportional_millionths);
 653                                         }
 654                                 }
 655                         }
 656
 657                         //TODO: satisfy the borrow-checker without a double-map-lookup :(
 658                         let mut_node = network.nodes.get_mut(&dest_node_id).unwrap();
 659                         mut_node.lowest_inbound_channel_fee_base_msat = lowest_inbound_channel_fee_base_msat;
 660                         mut_node.lowest_inbound_channel_fee_proportional_millionths = lowest_inbound_channel_fee_proportional_millionths;
 661                 }
 662
 663                 Ok(msg.contents.excess_data.is_empty())
 664         }
 665
 666
 667         fn get_next_channel_announcements(&self, starting_point: u64, batch_amount: u8) -> Vec<(msgs::ChannelAnnouncement, msgs::ChannelUpdate,msgs::ChannelUpdate)> {
 668                 let mut result = Vec::with_capacity(batch_amount as usize);
 669                 let network = self.network_map.read().unwrap();
 670                 let mut iter = network.channels.range(starting_point..);
 671                 while result.len() < batch_amount as usize {
 672                         if let Some((_, ref chan)) = iter.next() {
 673                                 if chan.announcement_message.is_some() &&
 674                                                 chan.one_to_two.last_update_message.is_some() &&
 675                                                 chan.two_to_one.last_update_message.is_some() {
 676                                         result.push((chan.announcement_message.clone().unwrap(),
 677                                                 chan.one_to_two.last_update_message.clone().unwrap(),
 678                                                 chan.two_to_one.last_update_message.clone().unwrap()));
 679                                 } else {
 680                                         // TODO: We may end up sending un-announced channel_updates if we are sending
 681                                         // initial sync data while receiving announce/updates for this channel.
 682                                 }
 683                         } else {
 684                                 return result;
 685                         }
 686                 }
 687                 result
 688         }
 689
 690         fn get_next_node_announcements(&self, starting_point: Option<&PublicKey>, batch_amount: u8) -> Vec<msgs::NodeAnnouncement> {
 691                 let mut result = Vec::with_capacity(batch_amount as usize);
 692                 let network = self.network_map.read().unwrap();
 693                 let mut iter = if let Some(pubkey) = starting_point {
 694                                 let mut iter = network.nodes.range((*pubkey)..);
 695                                 iter.next();
 696                                 iter
 697                         } else {
 698                                 network.nodes.range(..)
 699                         };
 700                 while result.len() < batch_amount as usize {
 701                         if let Some((_, ref node)) = iter.next() {
 702                                 if node.announcement_message.is_some() {
 703                                         result.push(node.announcement_message.clone().unwrap());
 704                                 }
 705                         } else {
 706                                 return result;
 707                         }
 708                 }
 709                 result
 710         }
 711
 712         fn should_request_full_sync(&self, _node_id: &PublicKey) -> bool {
 713                 //TODO: Determine whether to request a full sync based on the network map.
 714                 const FULL_SYNCS_TO_REQUEST: usize = 5;
 715                 if self.full_syncs_requested.load(Ordering::Acquire) < FULL_SYNCS_TO_REQUEST {
 716                         self.full_syncs_requested.fetch_add(1, Ordering::AcqRel);
 717                         true
 718                 } else {
 719                         false
 720                 }
 721         }
 722 }
 723
 724 #[derive(Eq, PartialEq)]
 725 struct RouteGraphNode {
 726         pubkey: PublicKey,
 727         lowest_fee_to_peer_through_node: u64,
 728         lowest_fee_to_node: u64,
 729 }
 730
 731 impl cmp::Ord for RouteGraphNode {
 732         fn cmp(&self, other: &RouteGraphNode) -> cmp::Ordering {
 733                 other.lowest_fee_to_peer_through_node.cmp(&self.lowest_fee_to_peer_through_node)
 734                         .then_with(|| other.pubkey.serialize().cmp(&self.pubkey.serialize()))
 735         }
 736 }
 737
 738 impl cmp::PartialOrd for RouteGraphNode {
 739         fn partial_cmp(&self, other: &RouteGraphNode) -> Option<cmp::Ordering> {
 740                 Some(self.cmp(other))
 741         }
 742 }
 743
 744 struct DummyDirectionalChannelInfo {
 745         src_node_id: PublicKey,
 746         cltv_expiry_delta: u32,
 747         htlc_minimum_msat: u64,
 748         fee_base_msat: u32,
 749         fee_proportional_millionths: u32,
 750 }
 751
 752 impl Router {
 753         /// Creates a new router with the given node_id to be used as the source for get_route()
 754         pub fn new(our_pubkey: PublicKey, chain_monitor: Arc<ChainWatchInterface>, logger: Arc<Logger>) -> Router {
 755                 let mut nodes = BTreeMap::new();
 756                 nodes.insert(our_pubkey.clone(), NodeInfo {
 757                         channels: Vec::new(),
 758                         lowest_inbound_channel_fee_base_msat: u32::max_value(),
 759                         lowest_inbound_channel_fee_proportional_millionths: u32::max_value(),
 760                         features: NodeFeatures::empty(),
 761                         last_update: None,
 762                         rgb: [0; 3],
 763                         alias: [0; 32],
 764                         addresses: Vec::new(),
 765                         announcement_message: None,
 766                 });
 767                 Router {
 768                         secp_ctx: Secp256k1::verification_only(),
 769                         network_map: RwLock::new(NetworkMap {
 770                                 channels: BTreeMap::new(),
 771                                 our_node_id: our_pubkey,
 772                                 nodes: nodes,
 773                         }),
 774                         full_syncs_requested: AtomicUsize::new(0),
 775                         chain_monitor,
 776                         logger,
 777                 }
 778         }
 779
 780         /// Dumps the entire network view of this Router to the logger provided in the constructor at
 781         /// level Trace
 782         pub fn trace_state(&self) {
 783                 log_trace!(self, "{}", self.network_map.read().unwrap());
 784         }
 785
 786         /// Get network addresses by node id
 787         pub fn get_addresses(&self, pubkey: &PublicKey) -> Option<Vec<NetAddress>> {
 788                 let network = self.network_map.read().unwrap();
 789                 network.nodes.get(pubkey).map(|n| n.addresses.clone())
 790         }
 791
 792         /// Marks a node as having failed a route. This will avoid re-using the node in routes for now,
 793         /// with an exponential decay in node "badness". Note that there is deliberately no
 794         /// mark_channel_bad as a node may simply lie and suggest that an upstream channel from it is
 795         /// what failed the route and not the node itself. Instead, setting the blamed_upstream_node
 796         /// boolean will reduce the penalty, returning the node to usability faster. If the node is
 797         /// behaving correctly, it will disable the failing channel and we will use it again next time.
 798         pub fn mark_node_bad(&self, _node_id: &PublicKey, _blamed_upstream_node: bool) {
 799                 unimplemented!();
 800         }
 801
 802         fn remove_channel_in_nodes(nodes: &mut BTreeMap<PublicKey, NodeInfo>, chan: &ChannelInfo, short_channel_id: u64) {
 803                 macro_rules! remove_from_node {
 804                         ($node_id: expr) => {
 805                                 if let BtreeEntry::Occupied(mut entry) = nodes.entry($node_id) {
 806                                         entry.get_mut().channels.retain(|chan_id| {
 807                                                 short_channel_id != *NetworkMap::get_short_id(chan_id)
 808                                         });
 809                                         if entry.get().channels.is_empty() {
 810                                                 entry.remove_entry();
 811                                         }
 812                                 } else {
 813                                         panic!("Had channel that pointed to unknown node (ie inconsistent network map)!");
 814                                 }
 815                         }
 816                 }
 817                 remove_from_node!(chan.one_to_two.src_node_id);
 818                 remove_from_node!(chan.two_to_one.src_node_id);
 819         }
 820
 821         /// Gets a route from us to the given target node.
 822         ///
 823         /// Extra routing hops between known nodes and the target will be used if they are included in
 824         /// last_hops.
 825         ///
 826         /// If some channels aren't announced, it may be useful to fill in a first_hops with the
 827         /// results from a local ChannelManager::list_usable_channels() call. If it is filled in, our
 828         /// (this Router's) view of our local channels will be ignored, and only those in first_hops
 829         /// will be used.
 830         ///
 831         /// Panics if first_hops contains channels without short_channel_ids
 832         /// (ChannelManager::list_usable_channels will never include such channels).
 833         ///
 834         /// The fees on channels from us to next-hops are ignored (as they are assumed to all be
 835         /// equal), however the enabled/disabled bit on such channels as well as the htlc_minimum_msat
 836         /// *is* checked as they may change based on the receiving node.
 837         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> {
 838                 // TODO: Obviously *only* using total fee cost sucks. We should consider weighting by
 839                 // uptime/success in using a node in the past.
 840                 let network = self.network_map.read().unwrap();
 841
 842                 if *target == network.our_node_id {
 843                         return Err(LightningError{err: "Cannot generate a route to ourselves", action: ErrorAction::IgnoreError});
 844                 }
 845
 846                 if final_value_msat > 21_000_000 * 1_0000_0000 * 1000 {
 847                         return Err(LightningError{err: "Cannot generate a route of more value than all existing satoshis", action: ErrorAction::IgnoreError});
 848                 }
 849
 850                 // We do a dest-to-source Dijkstra's sorting by each node's distance from the destination
 851                 // plus the minimum per-HTLC fee to get from it to another node (aka "shitty A*").
 852                 // TODO: There are a few tweaks we could do, including possibly pre-calculating more stuff
 853                 // to use as the A* heuristic beyond just the cost to get one node further than the current
 854                 // one.
 855
 856                 let dummy_directional_info = DummyDirectionalChannelInfo { // used for first_hops routes
 857                         src_node_id: network.our_node_id.clone(),
 858                         cltv_expiry_delta: 0,
 859                         htlc_minimum_msat: 0,
 860                         fee_base_msat: 0,
 861                         fee_proportional_millionths: 0,
 862                 };
 863
 864                 let mut targets = BinaryHeap::new(); //TODO: Do we care about switching to eg Fibbonaci heap?
 865                 let mut dist = HashMap::with_capacity(network.nodes.len());
 866
 867                 let mut first_hop_targets = HashMap::with_capacity(if first_hops.is_some() { first_hops.as_ref().unwrap().len() } else { 0 });
 868                 if let Some(hops) = first_hops {
 869                         for chan in hops {
 870                                 let short_channel_id = chan.short_channel_id.expect("first_hops should be filled in with usable channels, not pending ones");
 871                                 if chan.remote_network_id == *target {
 872                                         return Ok(Route {
 873                                                 hops: vec![RouteHop {
 874                                                         pubkey: chan.remote_network_id,
 875                                                         node_features: NodeFeatures::with_known_relevant_init_flags(&chan.counterparty_features),
 876                                                         short_channel_id,
 877                                                         channel_features: ChannelFeatures::with_known_relevant_init_flags(&chan.counterparty_features),
 878                                                         fee_msat: final_value_msat,
 879                                                         cltv_expiry_delta: final_cltv,
 880                                                 }],
 881                                         });
 882                                 }
 883                                 first_hop_targets.insert(chan.remote_network_id, (short_channel_id, chan.counterparty_features.clone()));
 884                         }
 885                         if first_hop_targets.is_empty() {
 886                                 return Err(LightningError{err: "Cannot route when there are no outbound routes away from us", action: ErrorAction::IgnoreError});
 887                         }
 888                 }
 889
 890                 macro_rules! add_entry {
 891                         // Adds entry which goes from the node pointed to by $directional_info to
 892                         // $dest_node_id over the channel with id $chan_id with fees described in
 893                         // $directional_info.
 894                         ( $chan_id: expr, $dest_node_id: expr, $directional_info: expr, $chan_features: expr, $starting_fee_msat: expr ) => {
 895                                 //TODO: Explore simply adding fee to hit htlc_minimum_msat
 896                                 if $starting_fee_msat as u64 + final_value_msat >= $directional_info.htlc_minimum_msat {
 897                                         let proportional_fee_millions = ($starting_fee_msat + final_value_msat).checked_mul($directional_info.fee_proportional_millionths as u64);
 898                                         if let Some(new_fee) = proportional_fee_millions.and_then(|part| {
 899                                                         ($directional_info.fee_base_msat as u64).checked_add(part / 1000000) })
 900                                         {
 901                                                 let mut total_fee = $starting_fee_msat as u64;
 902                                                 let hm_entry = dist.entry(&$directional_info.src_node_id);
 903                                                 let old_entry = hm_entry.or_insert_with(|| {
 904                                                         let node = network.nodes.get(&$directional_info.src_node_id).unwrap();
 905                                                         (u64::max_value(),
 906                                                                 node.lowest_inbound_channel_fee_base_msat,
 907                                                                 node.lowest_inbound_channel_fee_proportional_millionths,
 908                                                                 RouteHop {
 909                                                                         pubkey: $dest_node_id.clone(),
 910                                                                         node_features: NodeFeatures::empty(),
 911                                                                         short_channel_id: 0,
 912                                                                         channel_features: $chan_features.clone(),
 913                                                                         fee_msat: 0,
 914                                                                         cltv_expiry_delta: 0,
 915                                                         })
 916                                                 });
 917                                                 if $directional_info.src_node_id != network.our_node_id {
 918                                                         // Ignore new_fee for channel-from-us as we assume all channels-from-us
 919                                                         // will have the same effective-fee
 920                                                         total_fee += new_fee;
 921                                                         if let Some(fee_inc) = final_value_msat.checked_add(total_fee).and_then(|inc| { (old_entry.2 as u64).checked_mul(inc) }) {
 922                                                                 total_fee += fee_inc / 1000000 + (old_entry.1 as u64);
 923                                                         } else {
 924                                                                 // max_value means we'll always fail the old_entry.0 > total_fee check
 925                                                                 total_fee = u64::max_value();
 926                                                         }
 927                                                 }
 928                                                 let new_graph_node = RouteGraphNode {
 929                                                         pubkey: $directional_info.src_node_id,
 930                                                         lowest_fee_to_peer_through_node: total_fee,
 931                                                         lowest_fee_to_node: $starting_fee_msat as u64 + new_fee,
 932                                                 };
 933                                                 if old_entry.0 > total_fee {
 934                                                         targets.push(new_graph_node);
 935                                                         old_entry.0 = total_fee;
 936                                                         old_entry.3 = RouteHop {
 937                                                                 pubkey: $dest_node_id.clone(),
 938                                                                 node_features: NodeFeatures::empty(),
 939                                                                 short_channel_id: $chan_id.clone(),
 940                                                                 channel_features: $chan_features.clone(),
 941                                                                 fee_msat: new_fee, // This field is ignored on the last-hop anyway
 942                                                                 cltv_expiry_delta: $directional_info.cltv_expiry_delta as u32,
 943                                                         }
 944                                                 }
 945                                         }
 946                                 }
 947                         };
 948                 }
 949
 950                 macro_rules! add_entries_to_cheapest_to_target_node {
 951                         ( $node: expr, $node_id: expr, $fee_to_target_msat: expr ) => {
 952                                 if first_hops.is_some() {
 953                                         if let Some(&(ref first_hop, ref features)) = first_hop_targets.get(&$node_id) {
 954                                                 add_entry!(first_hop, $node_id, dummy_directional_info, ChannelFeatures::with_known_relevant_init_flags(&features), $fee_to_target_msat);
 955                                         }
 956                                 }
 957
 958                                 if !$node.features.requires_unknown_bits() {
 959                                         for chan_id in $node.channels.iter() {
 960                                                 let chan = network.channels.get(chan_id).unwrap();
 961                                                 if !chan.features.requires_unknown_bits() {
 962                                                         if chan.one_to_two.src_node_id == *$node_id {
 963                                                                 // ie $node is one, ie next hop in A* is two, via the two_to_one channel
 964                                                                 if first_hops.is_none() || chan.two_to_one.src_node_id != network.our_node_id {
 965                                                                         if chan.two_to_one.enabled {
 966                                                                                 add_entry!(chan_id, chan.one_to_two.src_node_id, chan.two_to_one, chan.features, $fee_to_target_msat);
 967                                                                         }
 968                                                                 }
 969                                                         } else {
 970                                                                 if first_hops.is_none() || chan.one_to_two.src_node_id != network.our_node_id {
 971                                                                         if chan.one_to_two.enabled {
 972                                                                                 add_entry!(chan_id, chan.two_to_one.src_node_id, chan.one_to_two, chan.features, $fee_to_target_msat);
 973                                                                         }
 974                                                                 }
 975                                                         }
 976                                                 }
 977                                         }
 978                                 }
 979                         };
 980                 }
 981
 982                 match network.nodes.get(target) {
 983                         None => {},
 984                         Some(node) => {
 985                                 add_entries_to_cheapest_to_target_node!(node, target, 0);
 986                         },
 987                 }
 988
 989                 for hop in last_hops.iter() {
 990                         if first_hops.is_none() || hop.src_node_id != network.our_node_id { // first_hop overrules last_hops
 991                                 if network.nodes.get(&hop.src_node_id).is_some() {
 992                                         if first_hops.is_some() {
 993                                                 if let Some(&(ref first_hop, ref features)) = first_hop_targets.get(&hop.src_node_id) {
 994                                                         // Currently there are no channel-context features defined, so we are a
 995                                                         // bit lazy here. In the future, we should pull them out via our
 996                                                         // ChannelManager, but there's no reason to waste the space until we
 997                                                         // need them.
 998                                                         add_entry!(first_hop, hop.src_node_id, dummy_directional_info, ChannelFeatures::with_known_relevant_init_flags(&features), 0);
 999                                                 }
1000                                         }
1001                                         // BOLT 11 doesn't allow inclusion of features for the last hop hints, which
1002                                         // really sucks, cause we're gonna need that eventually.
1003                                         add_entry!(hop.short_channel_id, target, hop, ChannelFeatures::empty(), 0);
1004                                 }
1005                         }
1006                 }
1007
1008                 while let Some(RouteGraphNode { pubkey, lowest_fee_to_node, .. }) = targets.pop() {
1009                         if pubkey == network.our_node_id {
1010                                 let mut res = vec!(dist.remove(&network.our_node_id).unwrap().3);
1011                                 loop {
1012                                         if let Some(&(_, ref features)) = first_hop_targets.get(&res.last().unwrap().pubkey) {
1013                                                 res.last_mut().unwrap().node_features = NodeFeatures::with_known_relevant_init_flags(&features);
1014                                         } else if let Some(node) = network.nodes.get(&res.last().unwrap().pubkey) {
1015                                                 res.last_mut().unwrap().node_features = node.features.clone();
1016                                         } else {
1017                                                 // We should be able to fill in features for everything except the last
1018                                                 // hop, if the last hop was provided via a BOLT 11 invoice (though we
1019                                                 // should be able to extend it further as BOLT 11 does have feature
1020                                                 // flags for the last hop node itself).
1021                                                 assert!(res.last().unwrap().pubkey == *target);
1022                                         }
1023                                         if res.last().unwrap().pubkey == *target {
1024                                                 break;
1025                                         }
1026
1027                                         let new_entry = match dist.remove(&res.last().unwrap().pubkey) {
1028                                                 Some(hop) => hop.3,
1029                                                 None => return Err(LightningError{err: "Failed to find a non-fee-overflowing path to the given destination", action: ErrorAction::IgnoreError}),
1030                                         };
1031                                         res.last_mut().unwrap().fee_msat = new_entry.fee_msat;
1032                                         res.last_mut().unwrap().cltv_expiry_delta = new_entry.cltv_expiry_delta;
1033                                         res.push(new_entry);
1034                                 }
1035                                 res.last_mut().unwrap().fee_msat = final_value_msat;
1036                                 res.last_mut().unwrap().cltv_expiry_delta = final_cltv;
1037                                 let route = Route { hops: res };
1038                                 log_trace!(self, "Got route: {}", log_route!(route));
1039                                 return Ok(route);
1040                         }
1041
1042                         match network.nodes.get(&pubkey) {
1043                                 None => {},
1044                                 Some(node) => {
1045                                         add_entries_to_cheapest_to_target_node!(node, &pubkey, lowest_fee_to_node);
1046                                 },
1047                         }
1048                 }
1049
1050                 Err(LightningError{err: "Failed to find a path to the given destination", action: ErrorAction::IgnoreError})
1051         }
1052 }
1053
1054 #[cfg(test)]
1055 mod tests {
1056         use chain::chaininterface;
1057         use ln::channelmanager;
1058         use ln::router::{Router,NodeInfo,NetworkMap,ChannelInfo,DirectionalChannelInfo,RouteHint};
1059         use ln::features::{ChannelFeatures, InitFeatures, NodeFeatures};
1060         use ln::msgs::{ErrorAction, LightningError, RoutingMessageHandler};
1061         use util::test_utils;
1062         use util::test_utils::TestVecWriter;
1063         use util::logger::Logger;
1064         use util::ser::{Writeable, Readable};
1065
1066         use bitcoin_hashes::sha256d::Hash as Sha256dHash;
1067         use bitcoin_hashes::Hash;
1068         use bitcoin::network::constants::Network;
1069
1070         use hex;
1071
1072         use secp256k1::key::{PublicKey,SecretKey};
1073         use secp256k1::All;
1074         use secp256k1::Secp256k1;
1075
1076         use std::sync::Arc;
1077
1078         fn create_router() -> (Secp256k1<All>, PublicKey, Router) {
1079                 let secp_ctx = Secp256k1::new();
1080                 let our_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap());
1081                 let logger: Arc<Logger> = Arc::new(test_utils::TestLogger::new());
1082                 let chain_monitor = Arc::new(chaininterface::ChainWatchInterfaceUtil::new(Network::Testnet, Arc::clone(&logger)));
1083                 let router = Router::new(our_id, chain_monitor, Arc::clone(&logger));
1084                 (secp_ctx, our_id, router)
1085         }
1086
1087         #[test]
1088         fn route_test() {
1089                 let (secp_ctx, our_id, router) = create_router();
1090
1091                 // Build network from our_id to node8:
1092                 //
1093                 //        -1(1)2-  node1  -1(3)2-
1094                 //       /                       \
1095                 // our_id -1(12)2- node8 -1(13)2--- node3
1096                 //       \                       /
1097                 //        -1(2)2-  node2  -1(4)2-
1098                 //
1099                 //
1100                 // chan1  1-to-2: disabled
1101                 // chan1  2-to-1: enabled, 0 fee
1102                 //
1103                 // chan2  1-to-2: enabled, ignored fee
1104                 // chan2  2-to-1: enabled, 0 fee
1105                 //
1106                 // chan3  1-to-2: enabled, 0 fee
1107                 // chan3  2-to-1: enabled, 100 msat fee
1108                 //
1109                 // chan4  1-to-2: enabled, 100% fee
1110                 // chan4  2-to-1: enabled, 0 fee
1111                 //
1112                 // chan12 1-to-2: enabled, ignored fee
1113                 // chan12 2-to-1: enabled, 0 fee
1114                 //
1115                 // chan13 1-to-2: enabled, 200% fee
1116                 // chan13 2-to-1: enabled, 0 fee
1117                 //
1118                 //
1119                 //       -1(5)2- node4 -1(8)2--
1120                 //       |         2          |
1121                 //       |       (11)         |
1122                 //      /          1           \
1123                 // node3--1(6)2- node5 -1(9)2--- node7 (not in global route map)
1124                 //      \                      /
1125                 //       -1(7)2- node6 -1(10)2-
1126                 //
1127                 // chan5  1-to-2: enabled, 100 msat fee
1128                 // chan5  2-to-1: enabled, 0 fee
1129                 //
1130                 // chan6  1-to-2: enabled, 0 fee
1131                 // chan6  2-to-1: enabled, 0 fee
1132                 //
1133                 // chan7  1-to-2: enabled, 100% fee
1134                 // chan7  2-to-1: enabled, 0 fee
1135                 //
1136                 // chan8  1-to-2: enabled, variable fee (0 then 1000 msat)
1137                 // chan8  2-to-1: enabled, 0 fee
1138                 //
1139                 // chan9  1-to-2: enabled, 1001 msat fee
1140                 // chan9  2-to-1: enabled, 0 fee
1141                 //
1142                 // chan10 1-to-2: enabled, 0 fee
1143                 // chan10 2-to-1: enabled, 0 fee
1144                 //
1145                 // chan11 1-to-2: enabled, 0 fee
1146                 // chan11 2-to-1: enabled, 0 fee
1147
1148                 let node1 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0202020202020202020202020202020202020202020202020202020202020202").unwrap()[..]).unwrap());
1149                 let node2 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0303030303030303030303030303030303030303030303030303030303030303").unwrap()[..]).unwrap());
1150                 let node3 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0404040404040404040404040404040404040404040404040404040404040404").unwrap()[..]).unwrap());
1151                 let node4 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0505050505050505050505050505050505050505050505050505050505050505").unwrap()[..]).unwrap());
1152                 let node5 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0606060606060606060606060606060606060606060606060606060606060606").unwrap()[..]).unwrap());
1153                 let node6 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0707070707070707070707070707070707070707070707070707070707070707").unwrap()[..]).unwrap());
1154                 let node7 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0808080808080808080808080808080808080808080808080808080808080808").unwrap()[..]).unwrap());
1155                 let node8 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0909090909090909090909090909090909090909090909090909090909090909").unwrap()[..]).unwrap());
1156
1157                 let zero_hash = Sha256dHash::hash(&[0; 32]);
1158
1159                 macro_rules! id_to_feature_flags {
1160                         // Set the feature flags to the id'th odd (ie non-required) feature bit so that we can
1161                         // test for it later.
1162                         ($id: expr) => { {
1163                                 let idx = ($id - 1) * 2 + 1;
1164                                 if idx > 8*3 {
1165                                         vec![1 << (idx - 8*3), 0, 0, 0]
1166                                 } else if idx > 8*2 {
1167                                         vec![1 << (idx - 8*2), 0, 0]
1168                                 } else if idx > 8*1 {
1169                                         vec![1 << (idx - 8*1), 0]
1170                                 } else {
1171                                         vec![1 << idx]
1172                                 }
1173                         } }
1174                 }
1175
1176                 {
1177                         let mut network = router.network_map.write().unwrap();
1178
1179                         network.nodes.insert(node1.clone(), NodeInfo {
1180                                 channels: vec!(NetworkMap::get_key(1, zero_hash.clone()), NetworkMap::get_key(3, zero_hash.clone())),
1181                                 lowest_inbound_channel_fee_base_msat: 100,
1182                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1183                                 features: NodeFeatures::from_le_bytes(id_to_feature_flags!(1)),
1184                                 last_update: Some(1),
1185                                 rgb: [0; 3],
1186                                 alias: [0; 32],
1187                                 addresses: Vec::new(),
1188                                 announcement_message: None,
1189                         });
1190                         network.channels.insert(NetworkMap::get_key(1, zero_hash.clone()), ChannelInfo {
1191                                 features: ChannelFeatures::from_le_bytes(id_to_feature_flags!(1)),
1192                                 one_to_two: DirectionalChannelInfo {
1193                                         src_node_id: our_id.clone(),
1194                                         last_update: 0,
1195                                         enabled: false,
1196                                         cltv_expiry_delta: u16::max_value(), // This value should be ignored
1197                                         htlc_minimum_msat: 0,
1198                                         fee_base_msat: u32::max_value(), // This value should be ignored
1199                                         fee_proportional_millionths: u32::max_value(), // This value should be ignored
1200                                         last_update_message: None,
1201                                 }, two_to_one: DirectionalChannelInfo {
1202                                         src_node_id: node1.clone(),
1203                                         last_update: 0,
1204                                         enabled: true,
1205                                         cltv_expiry_delta: 0,
1206                                         htlc_minimum_msat: 0,
1207                                         fee_base_msat: 0,
1208                                         fee_proportional_millionths: 0,
1209                                         last_update_message: None,
1210                                 },
1211                                 announcement_message: None,
1212                         });
1213                         network.nodes.insert(node2.clone(), NodeInfo {
1214                                 channels: vec!(NetworkMap::get_key(2, zero_hash.clone()), NetworkMap::get_key(4, zero_hash.clone())),
1215                                 lowest_inbound_channel_fee_base_msat: 0,
1216                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1217                                 features: NodeFeatures::from_le_bytes(id_to_feature_flags!(2)),
1218                                 last_update: Some(1),
1219                                 rgb: [0; 3],
1220                                 alias: [0; 32],
1221                                 addresses: Vec::new(),
1222                                 announcement_message: None,
1223                         });
1224                         network.channels.insert(NetworkMap::get_key(2, zero_hash.clone()), ChannelInfo {
1225                                 features: ChannelFeatures::from_le_bytes(id_to_feature_flags!(2)),
1226                                 one_to_two: DirectionalChannelInfo {
1227                                         src_node_id: our_id.clone(),
1228                                         last_update: 0,
1229                                         enabled: true,
1230                                         cltv_expiry_delta: u16::max_value(), // This value should be ignored
1231                                         htlc_minimum_msat: 0,
1232                                         fee_base_msat: u32::max_value(), // This value should be ignored
1233                                         fee_proportional_millionths: u32::max_value(), // This value should be ignored
1234                                         last_update_message: None,
1235                                 }, two_to_one: DirectionalChannelInfo {
1236                                         src_node_id: node2.clone(),
1237                                         last_update: 0,
1238                                         enabled: true,
1239                                         cltv_expiry_delta: 0,
1240                                         htlc_minimum_msat: 0,
1241                                         fee_base_msat: 0,
1242                                         fee_proportional_millionths: 0,
1243                                         last_update_message: None,
1244                                 },
1245                                 announcement_message: None,
1246                         });
1247                         network.nodes.insert(node8.clone(), NodeInfo {
1248                                 channels: vec!(NetworkMap::get_key(12, zero_hash.clone()), NetworkMap::get_key(13, zero_hash.clone())),
1249                                 lowest_inbound_channel_fee_base_msat: 0,
1250                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1251                                 features: NodeFeatures::from_le_bytes(id_to_feature_flags!(8)),
1252                                 last_update: Some(1),
1253                                 rgb: [0; 3],
1254                                 alias: [0; 32],
1255                                 addresses: Vec::new(),
1256                                 announcement_message: None,
1257                         });
1258                         network.channels.insert(NetworkMap::get_key(12, zero_hash.clone()), ChannelInfo {
1259                                 features: ChannelFeatures::from_le_bytes(id_to_feature_flags!(12)),
1260                                 one_to_two: DirectionalChannelInfo {
1261                                         src_node_id: our_id.clone(),
1262                                         last_update: 0,
1263                                         enabled: true,
1264                                         cltv_expiry_delta: u16::max_value(), // This value should be ignored
1265                                         htlc_minimum_msat: 0,
1266                                         fee_base_msat: u32::max_value(), // This value should be ignored
1267                                         fee_proportional_millionths: u32::max_value(), // This value should be ignored
1268                                         last_update_message: None,
1269                                 }, two_to_one: DirectionalChannelInfo {
1270                                         src_node_id: node8.clone(),
1271                                         last_update: 0,
1272                                         enabled: true,
1273                                         cltv_expiry_delta: 0,
1274                                         htlc_minimum_msat: 0,
1275                                         fee_base_msat: 0,
1276                                         fee_proportional_millionths: 0,
1277                                         last_update_message: None,
1278                                 },
1279                                 announcement_message: None,
1280                         });
1281                         network.nodes.insert(node3.clone(), NodeInfo {
1282                                 channels: vec!(
1283                                         NetworkMap::get_key(3, zero_hash.clone()),
1284                                         NetworkMap::get_key(4, zero_hash.clone()),
1285                                         NetworkMap::get_key(13, zero_hash.clone()),
1286                                         NetworkMap::get_key(5, zero_hash.clone()),
1287                                         NetworkMap::get_key(6, zero_hash.clone()),
1288                                         NetworkMap::get_key(7, zero_hash.clone())),
1289                                 lowest_inbound_channel_fee_base_msat: 0,
1290                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1291                                 features: NodeFeatures::from_le_bytes(id_to_feature_flags!(3)),
1292                                 last_update: Some(1),
1293                                 rgb: [0; 3],
1294                                 alias: [0; 32],
1295                                 addresses: Vec::new(),
1296                                 announcement_message: None,
1297                         });
1298                         network.channels.insert(NetworkMap::get_key(3, zero_hash.clone()), ChannelInfo {
1299                                 features: ChannelFeatures::from_le_bytes(id_to_feature_flags!(3)),
1300                                 one_to_two: DirectionalChannelInfo {
1301                                         src_node_id: node1.clone(),
1302                                         last_update: 0,
1303                                         enabled: true,
1304                                         cltv_expiry_delta: (3 << 8) | 1,
1305                                         htlc_minimum_msat: 0,
1306                                         fee_base_msat: 0,
1307                                         fee_proportional_millionths: 0,
1308                                         last_update_message: None,
1309                                 }, two_to_one: DirectionalChannelInfo {
1310                                         src_node_id: node3.clone(),
1311                                         last_update: 0,
1312                                         enabled: true,
1313                                         cltv_expiry_delta: (3 << 8) | 2,
1314                                         htlc_minimum_msat: 0,
1315                                         fee_base_msat: 100,
1316                                         fee_proportional_millionths: 0,
1317                                         last_update_message: None,
1318                                 },
1319                                 announcement_message: None,
1320                         });
1321                         network.channels.insert(NetworkMap::get_key(4, zero_hash.clone()), ChannelInfo {
1322                                 features: ChannelFeatures::from_le_bytes(id_to_feature_flags!(4)),
1323                                 one_to_two: DirectionalChannelInfo {
1324                                         src_node_id: node2.clone(),
1325                                         last_update: 0,
1326                                         enabled: true,
1327                                         cltv_expiry_delta: (4 << 8) | 1,
1328                                         htlc_minimum_msat: 0,
1329                                         fee_base_msat: 0,
1330                                         fee_proportional_millionths: 1000000,
1331                                         last_update_message: None,
1332                                 }, two_to_one: DirectionalChannelInfo {
1333                                         src_node_id: node3.clone(),
1334                                         last_update: 0,
1335                                         enabled: true,
1336                                         cltv_expiry_delta: (4 << 8) | 2,
1337                                         htlc_minimum_msat: 0,
1338                                         fee_base_msat: 0,
1339                                         fee_proportional_millionths: 0,
1340                                         last_update_message: None,
1341                                 },
1342                                 announcement_message: None,
1343                         });
1344                         network.channels.insert(NetworkMap::get_key(13, zero_hash.clone()), ChannelInfo {
1345                                 features: ChannelFeatures::from_le_bytes(id_to_feature_flags!(13)),
1346                                 one_to_two: DirectionalChannelInfo {
1347                                         src_node_id: node8.clone(),
1348                                         last_update: 0,
1349                                         enabled: true,
1350                                         cltv_expiry_delta: (13 << 8) | 1,
1351                                         htlc_minimum_msat: 0,
1352                                         fee_base_msat: 0,
1353                                         fee_proportional_millionths: 2000000,
1354                                         last_update_message: None,
1355                                 }, two_to_one: DirectionalChannelInfo {
1356                                         src_node_id: node3.clone(),
1357                                         last_update: 0,
1358                                         enabled: true,
1359                                         cltv_expiry_delta: (13 << 8) | 2,
1360                                         htlc_minimum_msat: 0,
1361                                         fee_base_msat: 0,
1362                                         fee_proportional_millionths: 0,
1363                                         last_update_message: None,
1364                                 },
1365                                 announcement_message: None,
1366                         });
1367                         network.nodes.insert(node4.clone(), NodeInfo {
1368                                 channels: vec!(NetworkMap::get_key(5, zero_hash.clone()), NetworkMap::get_key(11, zero_hash.clone())),
1369                                 lowest_inbound_channel_fee_base_msat: 0,
1370                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1371                                 features: NodeFeatures::from_le_bytes(id_to_feature_flags!(4)),
1372                                 last_update: Some(1),
1373                                 rgb: [0; 3],
1374                                 alias: [0; 32],
1375                                 addresses: Vec::new(),
1376                                 announcement_message: None,
1377                         });
1378                         network.channels.insert(NetworkMap::get_key(5, zero_hash.clone()), ChannelInfo {
1379                                 features: ChannelFeatures::from_le_bytes(id_to_feature_flags!(5)),
1380                                 one_to_two: DirectionalChannelInfo {
1381                                         src_node_id: node3.clone(),
1382                                         last_update: 0,
1383                                         enabled: true,
1384                                         cltv_expiry_delta: (5 << 8) | 1,
1385                                         htlc_minimum_msat: 0,
1386                                         fee_base_msat: 100,
1387                                         fee_proportional_millionths: 0,
1388                                         last_update_message: None,
1389                                 }, two_to_one: DirectionalChannelInfo {
1390                                         src_node_id: node4.clone(),
1391                                         last_update: 0,
1392                                         enabled: true,
1393                                         cltv_expiry_delta: (5 << 8) | 2,
1394                                         htlc_minimum_msat: 0,
1395                                         fee_base_msat: 0,
1396                                         fee_proportional_millionths: 0,
1397                                         last_update_message: None,
1398                                 },
1399                                 announcement_message: None,
1400                         });
1401                         network.nodes.insert(node5.clone(), NodeInfo {
1402                                 channels: vec!(NetworkMap::get_key(6, zero_hash.clone()), NetworkMap::get_key(11, zero_hash.clone())),
1403                                 lowest_inbound_channel_fee_base_msat: 0,
1404                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1405                                 features: NodeFeatures::from_le_bytes(id_to_feature_flags!(5)),
1406                                 last_update: Some(1),
1407                                 rgb: [0; 3],
1408                                 alias: [0; 32],
1409                                 addresses: Vec::new(),
1410                                 announcement_message: None,
1411                         });
1412                         network.channels.insert(NetworkMap::get_key(6, zero_hash.clone()), ChannelInfo {
1413                                 features: ChannelFeatures::from_le_bytes(id_to_feature_flags!(6)),
1414                                 one_to_two: DirectionalChannelInfo {
1415                                         src_node_id: node3.clone(),
1416                                         last_update: 0,
1417                                         enabled: true,
1418                                         cltv_expiry_delta: (6 << 8) | 1,
1419                                         htlc_minimum_msat: 0,
1420                                         fee_base_msat: 0,
1421                                         fee_proportional_millionths: 0,
1422                                         last_update_message: None,
1423                                 }, two_to_one: DirectionalChannelInfo {
1424                                         src_node_id: node5.clone(),
1425                                         last_update: 0,
1426                                         enabled: true,
1427                                         cltv_expiry_delta: (6 << 8) | 2,
1428                                         htlc_minimum_msat: 0,
1429                                         fee_base_msat: 0,
1430                                         fee_proportional_millionths: 0,
1431                                         last_update_message: None,
1432                                 },
1433                                 announcement_message: None,
1434                         });
1435                         network.channels.insert(NetworkMap::get_key(11, zero_hash.clone()), ChannelInfo {
1436                                 features: ChannelFeatures::from_le_bytes(id_to_feature_flags!(11)),
1437                                 one_to_two: DirectionalChannelInfo {
1438                                         src_node_id: node5.clone(),
1439                                         last_update: 0,
1440                                         enabled: true,
1441                                         cltv_expiry_delta: (11 << 8) | 1,
1442                                         htlc_minimum_msat: 0,
1443                                         fee_base_msat: 0,
1444                                         fee_proportional_millionths: 0,
1445                                         last_update_message: None,
1446                                 }, two_to_one: DirectionalChannelInfo {
1447                                         src_node_id: node4.clone(),
1448                                         last_update: 0,
1449                                         enabled: true,
1450                                         cltv_expiry_delta: (11 << 8) | 2,
1451                                         htlc_minimum_msat: 0,
1452                                         fee_base_msat: 0,
1453                                         fee_proportional_millionths: 0,
1454                                         last_update_message: None,
1455                                 },
1456                                 announcement_message: None,
1457                         });
1458                         network.nodes.insert(node6.clone(), NodeInfo {
1459                                 channels: vec!(NetworkMap::get_key(7, zero_hash.clone())),
1460                                 lowest_inbound_channel_fee_base_msat: 0,
1461                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1462                                 features: NodeFeatures::from_le_bytes(id_to_feature_flags!(6)),
1463                                 last_update: Some(1),
1464                                 rgb: [0; 3],
1465                                 alias: [0; 32],
1466                                 addresses: Vec::new(),
1467                                 announcement_message: None,
1468                         });
1469                         network.channels.insert(NetworkMap::get_key(7, zero_hash.clone()), ChannelInfo {
1470                                 features: ChannelFeatures::from_le_bytes(id_to_feature_flags!(7)),
1471                                 one_to_two: DirectionalChannelInfo {
1472                                         src_node_id: node3.clone(),
1473                                         last_update: 0,
1474                                         enabled: true,
1475                                         cltv_expiry_delta: (7 << 8) | 1,
1476                                         htlc_minimum_msat: 0,
1477                                         fee_base_msat: 0,
1478                                         fee_proportional_millionths: 1000000,
1479                                         last_update_message: None,
1480                                 }, two_to_one: DirectionalChannelInfo {
1481                                         src_node_id: node6.clone(),
1482                                         last_update: 0,
1483                                         enabled: true,
1484                                         cltv_expiry_delta: (7 << 8) | 2,
1485                                         htlc_minimum_msat: 0,
1486                                         fee_base_msat: 0,
1487                                         fee_proportional_millionths: 0,
1488                                         last_update_message: None,
1489                                 },
1490                                 announcement_message: None,
1491                         });
1492                 }
1493
1494                 { // Simple route to 3 via 2
1495                         let route = router.get_route(&node3, None, &Vec::new(), 100, 42).unwrap();
1496                         assert_eq!(route.hops.len(), 2);
1497
1498                         assert_eq!(route.hops[0].pubkey, node2);
1499                         assert_eq!(route.hops[0].short_channel_id, 2);
1500                         assert_eq!(route.hops[0].fee_msat, 100);
1501                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1502                         assert_eq!(route.hops[0].node_features.le_flags(), &id_to_feature_flags!(2));
1503                         assert_eq!(route.hops[0].channel_features.le_flags(), &id_to_feature_flags!(2));
1504
1505                         assert_eq!(route.hops[1].pubkey, node3);
1506                         assert_eq!(route.hops[1].short_channel_id, 4);
1507                         assert_eq!(route.hops[1].fee_msat, 100);
1508                         assert_eq!(route.hops[1].cltv_expiry_delta, 42);
1509                         assert_eq!(route.hops[1].node_features.le_flags(), &id_to_feature_flags!(3));
1510                         assert_eq!(route.hops[1].channel_features.le_flags(), &id_to_feature_flags!(4));
1511                 }
1512
1513                 { // Disable channels 4 and 12 by requiring unknown feature bits
1514                         let mut network = router.network_map.write().unwrap();
1515                         network.channels.get_mut(&NetworkMap::get_key(4, zero_hash.clone())).unwrap().features.set_require_unknown_bits();
1516                         network.channels.get_mut(&NetworkMap::get_key(12, zero_hash.clone())).unwrap().features.set_require_unknown_bits();
1517                 }
1518
1519                 { // If all the channels require some features we don't understand, route should fail
1520                         if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = router.get_route(&node3, None, &Vec::new(), 100, 42) {
1521                                 assert_eq!(err, "Failed to find a path to the given destination");
1522                         } else { panic!(); }
1523                 }
1524
1525                 { // If we specify a channel to node8, that overrides our local channel view and that gets used
1526                         let our_chans = vec![channelmanager::ChannelDetails {
1527                                 channel_id: [0; 32],
1528                                 short_channel_id: Some(42),
1529                                 remote_network_id: node8.clone(),
1530                                 counterparty_features: InitFeatures::from_le_bytes(vec![0b11]),
1531                                 channel_value_satoshis: 0,
1532                                 user_id: 0,
1533                                 outbound_capacity_msat: 0,
1534                                 inbound_capacity_msat: 0,
1535                                 is_live: true,
1536                         }];
1537                         let route = router.get_route(&node3, Some(&our_chans), &Vec::new(), 100, 42).unwrap();
1538                         assert_eq!(route.hops.len(), 2);
1539
1540                         assert_eq!(route.hops[0].pubkey, node8);
1541                         assert_eq!(route.hops[0].short_channel_id, 42);
1542                         assert_eq!(route.hops[0].fee_msat, 200);
1543                         assert_eq!(route.hops[0].cltv_expiry_delta, (13 << 8) | 1);
1544                         assert_eq!(route.hops[0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
1545                         assert_eq!(route.hops[0].channel_features.le_flags(), &Vec::new()); // No feature flags will meet the relevant-to-channel conversion
1546
1547                         assert_eq!(route.hops[1].pubkey, node3);
1548                         assert_eq!(route.hops[1].short_channel_id, 13);
1549                         assert_eq!(route.hops[1].fee_msat, 100);
1550                         assert_eq!(route.hops[1].cltv_expiry_delta, 42);
1551                         assert_eq!(route.hops[1].node_features.le_flags(), &id_to_feature_flags!(3));
1552                         assert_eq!(route.hops[1].channel_features.le_flags(), &id_to_feature_flags!(13));
1553                 }
1554
1555                 { // Re-enable channels 4 and 12 by wiping the unknown feature bits
1556                         let mut network = router.network_map.write().unwrap();
1557                         network.channels.get_mut(&NetworkMap::get_key(4, zero_hash.clone())).unwrap().features.clear_require_unknown_bits();
1558                         network.channels.get_mut(&NetworkMap::get_key(12, zero_hash.clone())).unwrap().features.clear_require_unknown_bits();
1559                 }
1560
1561                 { // Disable nodes 1, 2, and 8 by requiring unknown feature bits
1562                         let mut network = router.network_map.write().unwrap();
1563                         network.nodes.get_mut(&node1).unwrap().features.set_require_unknown_bits();
1564                         network.nodes.get_mut(&node2).unwrap().features.set_require_unknown_bits();
1565                         network.nodes.get_mut(&node8).unwrap().features.set_require_unknown_bits();
1566                 }
1567
1568                 { // If all nodes require some features we don't understand, route should fail
1569                         if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = router.get_route(&node3, None, &Vec::new(), 100, 42) {
1570                                 assert_eq!(err, "Failed to find a path to the given destination");
1571                         } else { panic!(); }
1572                 }
1573
1574                 { // If we specify a channel to node8, that overrides our local channel view and that gets used
1575                         let our_chans = vec![channelmanager::ChannelDetails {
1576                                 channel_id: [0; 32],
1577                                 short_channel_id: Some(42),
1578                                 remote_network_id: node8.clone(),
1579                                 counterparty_features: InitFeatures::from_le_bytes(vec![0b11]),
1580                                 channel_value_satoshis: 0,
1581                                 user_id: 0,
1582                                 outbound_capacity_msat: 0,
1583                                 inbound_capacity_msat: 0,
1584                                 is_live: true,
1585                         }];
1586                         let route = router.get_route(&node3, Some(&our_chans), &Vec::new(), 100, 42).unwrap();
1587                         assert_eq!(route.hops.len(), 2);
1588
1589                         assert_eq!(route.hops[0].pubkey, node8);
1590                         assert_eq!(route.hops[0].short_channel_id, 42);
1591                         assert_eq!(route.hops[0].fee_msat, 200);
1592                         assert_eq!(route.hops[0].cltv_expiry_delta, (13 << 8) | 1);
1593                         assert_eq!(route.hops[0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
1594                         assert_eq!(route.hops[0].channel_features.le_flags(), &Vec::new()); // No feature flags will meet the relevant-to-channel conversion
1595
1596                         assert_eq!(route.hops[1].pubkey, node3);
1597                         assert_eq!(route.hops[1].short_channel_id, 13);
1598                         assert_eq!(route.hops[1].fee_msat, 100);
1599                         assert_eq!(route.hops[1].cltv_expiry_delta, 42);
1600                         assert_eq!(route.hops[1].node_features.le_flags(), &id_to_feature_flags!(3));
1601                         assert_eq!(route.hops[1].channel_features.le_flags(), &id_to_feature_flags!(13));
1602                 }
1603
1604                 { // Re-enable nodes 1, 2, and 8
1605                         let mut network = router.network_map.write().unwrap();
1606                         network.nodes.get_mut(&node1).unwrap().features.clear_require_unknown_bits();
1607                         network.nodes.get_mut(&node2).unwrap().features.clear_require_unknown_bits();
1608                         network.nodes.get_mut(&node8).unwrap().features.clear_require_unknown_bits();
1609                 }
1610
1611                 // Note that we don't test disabling node 3 and failing to route to it, as we (somewhat
1612                 // naively) assume that the user checked the feature bits on the invoice, which override
1613                 // the node_announcement.
1614
1615                 { // Route to 1 via 2 and 3 because our channel to 1 is disabled
1616                         let route = router.get_route(&node1, None, &Vec::new(), 100, 42).unwrap();
1617                         assert_eq!(route.hops.len(), 3);
1618
1619                         assert_eq!(route.hops[0].pubkey, node2);
1620                         assert_eq!(route.hops[0].short_channel_id, 2);
1621                         assert_eq!(route.hops[0].fee_msat, 200);
1622                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1623                         assert_eq!(route.hops[0].node_features.le_flags(), &id_to_feature_flags!(2));
1624                         assert_eq!(route.hops[0].channel_features.le_flags(), &id_to_feature_flags!(2));
1625
1626                         assert_eq!(route.hops[1].pubkey, node3);
1627                         assert_eq!(route.hops[1].short_channel_id, 4);
1628                         assert_eq!(route.hops[1].fee_msat, 100);
1629                         assert_eq!(route.hops[1].cltv_expiry_delta, (3 << 8) | 2);
1630                         assert_eq!(route.hops[1].node_features.le_flags(), &id_to_feature_flags!(3));
1631                         assert_eq!(route.hops[1].channel_features.le_flags(), &id_to_feature_flags!(4));
1632
1633                         assert_eq!(route.hops[2].pubkey, node1);
1634                         assert_eq!(route.hops[2].short_channel_id, 3);
1635                         assert_eq!(route.hops[2].fee_msat, 100);
1636                         assert_eq!(route.hops[2].cltv_expiry_delta, 42);
1637                         assert_eq!(route.hops[2].node_features.le_flags(), &id_to_feature_flags!(1));
1638                         assert_eq!(route.hops[2].channel_features.le_flags(), &id_to_feature_flags!(3));
1639                 }
1640
1641                 { // If we specify a channel to node8, that overrides our local channel view and that gets used
1642                         let our_chans = vec![channelmanager::ChannelDetails {
1643                                 channel_id: [0; 32],
1644                                 short_channel_id: Some(42),
1645                                 remote_network_id: node8.clone(),
1646                                 counterparty_features: InitFeatures::from_le_bytes(vec![0b11]),
1647                                 channel_value_satoshis: 0,
1648                                 user_id: 0,
1649                                 outbound_capacity_msat: 0,
1650                                 inbound_capacity_msat: 0,
1651                                 is_live: true,
1652                         }];
1653                         let route = router.get_route(&node3, Some(&our_chans), &Vec::new(), 100, 42).unwrap();
1654                         assert_eq!(route.hops.len(), 2);
1655
1656                         assert_eq!(route.hops[0].pubkey, node8);
1657                         assert_eq!(route.hops[0].short_channel_id, 42);
1658                         assert_eq!(route.hops[0].fee_msat, 200);
1659                         assert_eq!(route.hops[0].cltv_expiry_delta, (13 << 8) | 1);
1660                         assert_eq!(route.hops[0].node_features.le_flags(), &vec![0b11]);
1661                         assert_eq!(route.hops[0].channel_features.le_flags(), &Vec::new()); // No feature flags will meet the relevant-to-channel conversion
1662
1663                         assert_eq!(route.hops[1].pubkey, node3);
1664                         assert_eq!(route.hops[1].short_channel_id, 13);
1665                         assert_eq!(route.hops[1].fee_msat, 100);
1666                         assert_eq!(route.hops[1].cltv_expiry_delta, 42);
1667                         assert_eq!(route.hops[1].node_features.le_flags(), &id_to_feature_flags!(3));
1668                         assert_eq!(route.hops[1].channel_features.le_flags(), &id_to_feature_flags!(13));
1669                 }
1670
1671                 let mut last_hops = vec!(RouteHint {
1672                                 src_node_id: node4.clone(),
1673                                 short_channel_id: 8,
1674                                 fee_base_msat: 0,
1675                                 fee_proportional_millionths: 0,
1676                                 cltv_expiry_delta: (8 << 8) | 1,
1677                                 htlc_minimum_msat: 0,
1678                         }, RouteHint {
1679                                 src_node_id: node5.clone(),
1680                                 short_channel_id: 9,
1681                                 fee_base_msat: 1001,
1682                                 fee_proportional_millionths: 0,
1683                                 cltv_expiry_delta: (9 << 8) | 1,
1684                                 htlc_minimum_msat: 0,
1685                         }, RouteHint {
1686                                 src_node_id: node6.clone(),
1687                                 short_channel_id: 10,
1688                                 fee_base_msat: 0,
1689                                 fee_proportional_millionths: 0,
1690                                 cltv_expiry_delta: (10 << 8) | 1,
1691                                 htlc_minimum_msat: 0,
1692                         });
1693
1694                 { // Simple test across 2, 3, 5, and 4 via a last_hop channel
1695                         let route = router.get_route(&node7, None, &last_hops, 100, 42).unwrap();
1696                         assert_eq!(route.hops.len(), 5);
1697
1698                         assert_eq!(route.hops[0].pubkey, node2);
1699                         assert_eq!(route.hops[0].short_channel_id, 2);
1700                         assert_eq!(route.hops[0].fee_msat, 100);
1701                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1702                         assert_eq!(route.hops[0].node_features.le_flags(), &id_to_feature_flags!(2));
1703                         assert_eq!(route.hops[0].channel_features.le_flags(), &id_to_feature_flags!(2));
1704
1705                         assert_eq!(route.hops[1].pubkey, node3);
1706                         assert_eq!(route.hops[1].short_channel_id, 4);
1707                         assert_eq!(route.hops[1].fee_msat, 0);
1708                         assert_eq!(route.hops[1].cltv_expiry_delta, (6 << 8) | 1);
1709                         assert_eq!(route.hops[1].node_features.le_flags(), &id_to_feature_flags!(3));
1710                         assert_eq!(route.hops[1].channel_features.le_flags(), &id_to_feature_flags!(4));
1711
1712                         assert_eq!(route.hops[2].pubkey, node5);
1713                         assert_eq!(route.hops[2].short_channel_id, 6);
1714                         assert_eq!(route.hops[2].fee_msat, 0);
1715                         assert_eq!(route.hops[2].cltv_expiry_delta, (11 << 8) | 1);
1716                         assert_eq!(route.hops[2].node_features.le_flags(), &id_to_feature_flags!(5));
1717                         assert_eq!(route.hops[2].channel_features.le_flags(), &id_to_feature_flags!(6));
1718
1719                         assert_eq!(route.hops[3].pubkey, node4);
1720                         assert_eq!(route.hops[3].short_channel_id, 11);
1721                         assert_eq!(route.hops[3].fee_msat, 0);
1722                         assert_eq!(route.hops[3].cltv_expiry_delta, (8 << 8) | 1);
1723                         // If we have a peer in the node map, we'll use their features here since we don't have
1724                         // a way of figuring out their features from the invoice:
1725                         assert_eq!(route.hops[3].node_features.le_flags(), &id_to_feature_flags!(4));
1726                         assert_eq!(route.hops[3].channel_features.le_flags(), &id_to_feature_flags!(11));
1727
1728                         assert_eq!(route.hops[4].pubkey, node7);
1729                         assert_eq!(route.hops[4].short_channel_id, 8);
1730                         assert_eq!(route.hops[4].fee_msat, 100);
1731                         assert_eq!(route.hops[4].cltv_expiry_delta, 42);
1732                         assert_eq!(route.hops[4].node_features.le_flags(), &Vec::new()); // We dont pass flags in from invoices yet
1733                         assert_eq!(route.hops[4].channel_features.le_flags(), &Vec::new()); // We can't learn any flags from invoices, sadly
1734                 }
1735
1736                 { // Simple test with outbound channel to 4 to test that last_hops and first_hops connect
1737                         let our_chans = vec![channelmanager::ChannelDetails {
1738                                 channel_id: [0; 32],
1739                                 short_channel_id: Some(42),
1740                                 remote_network_id: node4.clone(),
1741                                 counterparty_features: InitFeatures::from_le_bytes(vec![0b11]),
1742                                 channel_value_satoshis: 0,
1743                                 user_id: 0,
1744                                 outbound_capacity_msat: 0,
1745                                 inbound_capacity_msat: 0,
1746                                 is_live: true,
1747                         }];
1748                         let route = router.get_route(&node7, Some(&our_chans), &last_hops, 100, 42).unwrap();
1749                         assert_eq!(route.hops.len(), 2);
1750
1751                         assert_eq!(route.hops[0].pubkey, node4);
1752                         assert_eq!(route.hops[0].short_channel_id, 42);
1753                         assert_eq!(route.hops[0].fee_msat, 0);
1754                         assert_eq!(route.hops[0].cltv_expiry_delta, (8 << 8) | 1);
1755                         assert_eq!(route.hops[0].node_features.le_flags(), &vec![0b11]);
1756                         assert_eq!(route.hops[0].channel_features.le_flags(), &Vec::new()); // No feature flags will meet the relevant-to-channel conversion
1757
1758                         assert_eq!(route.hops[1].pubkey, node7);
1759                         assert_eq!(route.hops[1].short_channel_id, 8);
1760                         assert_eq!(route.hops[1].fee_msat, 100);
1761                         assert_eq!(route.hops[1].cltv_expiry_delta, 42);
1762                         assert_eq!(route.hops[1].node_features.le_flags(), &Vec::new()); // We dont pass flags in from invoices yet
1763                         assert_eq!(route.hops[1].channel_features.le_flags(), &Vec::new()); // We can't learn any flags from invoices, sadly
1764                 }
1765
1766                 last_hops[0].fee_base_msat = 1000;
1767
1768                 { // Revert to via 6 as the fee on 8 goes up
1769                         let route = router.get_route(&node7, None, &last_hops, 100, 42).unwrap();
1770                         assert_eq!(route.hops.len(), 4);
1771
1772                         assert_eq!(route.hops[0].pubkey, node2);
1773                         assert_eq!(route.hops[0].short_channel_id, 2);
1774                         assert_eq!(route.hops[0].fee_msat, 200); // fee increased as its % of value transferred across node
1775                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1776                         assert_eq!(route.hops[0].node_features.le_flags(), &id_to_feature_flags!(2));
1777                         assert_eq!(route.hops[0].channel_features.le_flags(), &id_to_feature_flags!(2));
1778
1779                         assert_eq!(route.hops[1].pubkey, node3);
1780                         assert_eq!(route.hops[1].short_channel_id, 4);
1781                         assert_eq!(route.hops[1].fee_msat, 100);
1782                         assert_eq!(route.hops[1].cltv_expiry_delta, (7 << 8) | 1);
1783                         assert_eq!(route.hops[1].node_features.le_flags(), &id_to_feature_flags!(3));
1784                         assert_eq!(route.hops[1].channel_features.le_flags(), &id_to_feature_flags!(4));
1785
1786                         assert_eq!(route.hops[2].pubkey, node6);
1787                         assert_eq!(route.hops[2].short_channel_id, 7);
1788                         assert_eq!(route.hops[2].fee_msat, 0);
1789                         assert_eq!(route.hops[2].cltv_expiry_delta, (10 << 8) | 1);
1790                         // If we have a peer in the node map, we'll use their features here since we don't have
1791                         // a way of figuring out their features from the invoice:
1792                         assert_eq!(route.hops[2].node_features.le_flags(), &id_to_feature_flags!(6));
1793                         assert_eq!(route.hops[2].channel_features.le_flags(), &id_to_feature_flags!(7));
1794
1795                         assert_eq!(route.hops[3].pubkey, node7);
1796                         assert_eq!(route.hops[3].short_channel_id, 10);
1797                         assert_eq!(route.hops[3].fee_msat, 100);
1798                         assert_eq!(route.hops[3].cltv_expiry_delta, 42);
1799                         assert_eq!(route.hops[3].node_features.le_flags(), &Vec::new()); // We dont pass flags in from invoices yet
1800                         assert_eq!(route.hops[3].channel_features.le_flags(), &Vec::new()); // We can't learn any flags from invoices, sadly
1801                 }
1802
1803                 { // ...but still use 8 for larger payments as 6 has a variable feerate
1804                         let route = router.get_route(&node7, None, &last_hops, 2000, 42).unwrap();
1805                         assert_eq!(route.hops.len(), 5);
1806
1807                         assert_eq!(route.hops[0].pubkey, node2);
1808                         assert_eq!(route.hops[0].short_channel_id, 2);
1809                         assert_eq!(route.hops[0].fee_msat, 3000);
1810                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1811                         assert_eq!(route.hops[0].node_features.le_flags(), &id_to_feature_flags!(2));
1812                         assert_eq!(route.hops[0].channel_features.le_flags(), &id_to_feature_flags!(2));
1813
1814                         assert_eq!(route.hops[1].pubkey, node3);
1815                         assert_eq!(route.hops[1].short_channel_id, 4);
1816                         assert_eq!(route.hops[1].fee_msat, 0);
1817                         assert_eq!(route.hops[1].cltv_expiry_delta, (6 << 8) | 1);
1818                         assert_eq!(route.hops[1].node_features.le_flags(), &id_to_feature_flags!(3));
1819                         assert_eq!(route.hops[1].channel_features.le_flags(), &id_to_feature_flags!(4));
1820
1821                         assert_eq!(route.hops[2].pubkey, node5);
1822                         assert_eq!(route.hops[2].short_channel_id, 6);
1823                         assert_eq!(route.hops[2].fee_msat, 0);
1824                         assert_eq!(route.hops[2].cltv_expiry_delta, (11 << 8) | 1);
1825                         assert_eq!(route.hops[2].node_features.le_flags(), &id_to_feature_flags!(5));
1826                         assert_eq!(route.hops[2].channel_features.le_flags(), &id_to_feature_flags!(6));
1827
1828                         assert_eq!(route.hops[3].pubkey, node4);
1829                         assert_eq!(route.hops[3].short_channel_id, 11);
1830                         assert_eq!(route.hops[3].fee_msat, 1000);
1831                         assert_eq!(route.hops[3].cltv_expiry_delta, (8 << 8) | 1);
1832                         // If we have a peer in the node map, we'll use their features here since we don't have
1833                         // a way of figuring out their features from the invoice:
1834                         assert_eq!(route.hops[3].node_features.le_flags(), &id_to_feature_flags!(4));
1835                         assert_eq!(route.hops[3].channel_features.le_flags(), &id_to_feature_flags!(11));
1836
1837                         assert_eq!(route.hops[4].pubkey, node7);
1838                         assert_eq!(route.hops[4].short_channel_id, 8);
1839                         assert_eq!(route.hops[4].fee_msat, 2000);
1840                         assert_eq!(route.hops[4].cltv_expiry_delta, 42);
1841                         assert_eq!(route.hops[4].node_features.le_flags(), &Vec::new()); // We dont pass flags in from invoices yet
1842                         assert_eq!(route.hops[4].channel_features.le_flags(), &Vec::new()); // We can't learn any flags from invoices, sadly
1843                 }
1844
1845                 { // Test Router serialization/deserialization
1846                         let mut w = TestVecWriter(Vec::new());
1847                         let network = router.network_map.read().unwrap();
1848                         assert!(!network.channels.is_empty());
1849                         assert!(!network.nodes.is_empty());
1850                         network.write(&mut w).unwrap();
1851                         assert!(<NetworkMap>::read(&mut ::std::io::Cursor::new(&w.0)).unwrap() == *network);
1852                 }
1853         }
1854
1855         #[test]
1856         fn request_full_sync_finite_times() {
1857                 let (secp_ctx, _, router) = create_router();
1858                 let node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode("0202020202020202020202020202020202020202020202020202020202020202").unwrap()[..]).unwrap());
1859
1860                 assert!(router.should_request_full_sync(&node_id));
1861                 assert!(router.should_request_full_sync(&node_id));
1862                 assert!(router.should_request_full_sync(&node_id));
1863                 assert!(router.should_request_full_sync(&node_id));
1864                 assert!(router.should_request_full_sync(&node_id));
1865                 assert!(!router.should_request_full_sync(&node_id));
1866         }
1867 }