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

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