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

   1 use secp256k1::key::PublicKey;
   2 use secp256k1::{Secp256k1,Message};
   3 use secp256k1;
   4
   5 use bitcoin::util::hash::Sha256dHash;
   6
   7 use chain::chaininterface::{ChainError, ChainWatchInterface};
   8 use ln::channelmanager;
   9 use ln::msgs::{ErrorAction,HandleError,RoutingMessageHandler,MsgEncodable,NetAddress,GlobalFeatures};
  10 use ln::msgs;
  11 use util::logger::Logger;
  12
  13 use std::cmp;
  14 use std::sync::{RwLock,Arc};
  15 use std::collections::{HashMap,BinaryHeap};
  16 use std::collections::hash_map::Entry;
  17 use std;
  18
  19 /// A hop in a route
  20 #[derive(Clone)]
  21 pub struct RouteHop {
  22         pub pubkey: PublicKey,
  23         /// The channel that should be used from the previous hop to reach this node.
  24         pub short_channel_id: u64,
  25         /// The fee taken on this hop. For the last hop, this should be the full value of the payment.
  26         pub fee_msat: u64,
  27         /// The CLTV delta added for this hop. For the last hop, this should be the full CLTV value
  28         /// expected at the destination, in excess of the current block height.
  29         pub cltv_expiry_delta: u32,
  30 }
  31
  32 /// A route from us through the network to a destination
  33 #[derive(Clone)]
  34 pub struct Route {
  35         /// The list of hops, NOT INCLUDING our own, where the last hop is the destination. Thus, this
  36         /// must always be at least length one. By protocol rules, this may not currently exceed 20 in
  37         /// length.
  38         pub hops: Vec<RouteHop>,
  39 }
  40
  41 struct DirectionalChannelInfo {
  42         src_node_id: PublicKey,
  43         last_update: u32,
  44         enabled: bool,
  45         cltv_expiry_delta: u16,
  46         htlc_minimum_msat: u64,
  47         fee_base_msat: u32,
  48         fee_proportional_millionths: u32,
  49 }
  50
  51 impl std::fmt::Display for DirectionalChannelInfo {
  52         fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
  53                 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)?;
  54                 Ok(())
  55         }
  56 }
  57
  58 struct ChannelInfo {
  59         features: GlobalFeatures,
  60         one_to_two: DirectionalChannelInfo,
  61         two_to_one: DirectionalChannelInfo,
  62 }
  63
  64 impl std::fmt::Display for ChannelInfo {
  65         fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
  66                 write!(f, "features: {}, one_to_two: {}, two_to_one: {}", log_bytes!(self.features.encode()), self.one_to_two, self.two_to_one)?;
  67                 Ok(())
  68         }
  69 }
  70
  71 struct NodeInfo {
  72         #[cfg(feature = "non_bitcoin_chain_hash_routing")]
  73         channels: Vec<(u64, Sha256dHash)>,
  74         #[cfg(not(feature = "non_bitcoin_chain_hash_routing"))]
  75         channels: Vec<u64>,
  76
  77         lowest_inbound_channel_fee_base_msat: u32,
  78         lowest_inbound_channel_fee_proportional_millionths: u32,
  79
  80         features: GlobalFeatures,
  81         last_update: u32,
  82         rgb: [u8; 3],
  83         alias: [u8; 32],
  84         addresses: Vec<NetAddress>,
  85 }
  86
  87 impl std::fmt::Display for NodeInfo {
  88         fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
  89                 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[..])?;
  90                 Ok(())
  91         }
  92 }
  93
  94 struct NetworkMap {
  95         #[cfg(feature = "non_bitcoin_chain_hash_routing")]
  96         channels: HashMap<(u64, Sha256dHash), ChannelInfo>,
  97         #[cfg(not(feature = "non_bitcoin_chain_hash_routing"))]
  98         channels: HashMap<u64, ChannelInfo>,
  99
 100         our_node_id: PublicKey,
 101         nodes: HashMap<PublicKey, NodeInfo>,
 102 }
 103
 104 impl std::fmt::Display for NetworkMap {
 105         fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
 106                 write!(f, "Node id {} network map\n[Channels]\n", log_pubkey!(self.our_node_id))?;
 107                 for (key, val) in self.channels.iter() {
 108                         write!(f, " {}: {}\n", key, val)?;
 109                 }
 110                 write!(f, "[Nodes]\n")?;
 111                 for (key, val) in self.nodes.iter() {
 112                         write!(f, " {}: {}\n", log_pubkey!(key), val)?;
 113                 }
 114                 Ok(())
 115         }
 116 }
 117
 118 impl NetworkMap {
 119         #[cfg(feature = "non_bitcoin_chain_hash_routing")]
 120         #[inline]
 121         fn get_key(short_channel_id: u64, chain_hash: Sha256dHash) -> (u64, Sha256dHash) {
 122                 (short_channel_id, chain_hash)
 123         }
 124
 125         #[cfg(not(feature = "non_bitcoin_chain_hash_routing"))]
 126         #[inline]
 127         fn get_key(short_channel_id: u64, _: Sha256dHash) -> u64 {
 128                 short_channel_id
 129         }
 130
 131         #[cfg(feature = "non_bitcoin_chain_hash_routing")]
 132         #[inline]
 133         fn get_short_id(id: &(u64, Sha256dHash)) -> &u64 {
 134                 &id.0
 135         }
 136
 137         #[cfg(not(feature = "non_bitcoin_chain_hash_routing"))]
 138         #[inline]
 139         fn get_short_id(id: &u64) -> &u64 {
 140                 id
 141         }
 142 }
 143
 144 /// A channel descriptor which provides a last-hop route to get_route
 145 pub struct RouteHint {
 146         pub src_node_id: PublicKey,
 147         pub short_channel_id: u64,
 148         pub fee_base_msat: u32,
 149         pub fee_proportional_millionths: u32,
 150         pub cltv_expiry_delta: u16,
 151         pub htlc_minimum_msat: u64,
 152 }
 153
 154 /// Tracks a view of the network, receiving updates from peers and generating Routes to
 155 /// payment destinations.
 156 pub struct Router {
 157         secp_ctx: Secp256k1<secp256k1::VerifyOnly>,
 158         network_map: RwLock<NetworkMap>,
 159         chain_monitor: Arc<ChainWatchInterface>,
 160         logger: Arc<Logger>,
 161 }
 162
 163 macro_rules! secp_verify_sig {
 164         ( $secp_ctx: expr, $msg: expr, $sig: expr, $pubkey: expr ) => {
 165                 match $secp_ctx.verify($msg, $sig, $pubkey) {
 166                         Ok(_) => {},
 167                         Err(_) => return Err(HandleError{err: "Invalid signature from remote node", action: None}),
 168                 }
 169         };
 170 }
 171
 172 impl RoutingMessageHandler for Router {
 173         fn handle_node_announcement(&self, msg: &msgs::NodeAnnouncement) -> Result<bool, HandleError> {
 174                 let msg_hash = Message::from_slice(&Sha256dHash::from_data(&msg.contents.encode()[..])[..]).unwrap();
 175                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.signature, &msg.contents.node_id);
 176
 177                 if msg.contents.features.requires_unknown_bits() {
 178                         panic!("Unknown-required-features NodeAnnouncements should never deserialize!");
 179                 }
 180
 181                 let mut network = self.network_map.write().unwrap();
 182                 match network.nodes.get_mut(&msg.contents.node_id) {
 183                         None => Err(HandleError{err: "No existing channels for node_announcement", action: Some(ErrorAction::IgnoreError)}),
 184                         Some(node) => {
 185                                 if node.last_update >= msg.contents.timestamp {
 186                                         return Err(HandleError{err: "Update older than last processed update", action: Some(ErrorAction::IgnoreError)});
 187                                 }
 188
 189                                 node.features = msg.contents.features.clone();
 190                                 node.last_update = msg.contents.timestamp;
 191                                 node.rgb = msg.contents.rgb;
 192                                 node.alias = msg.contents.alias;
 193                                 node.addresses = msg.contents.addresses.clone();
 194                                 Ok(msg.contents.excess_data.is_empty() && msg.contents.excess_address_data.is_empty() && !msg.contents.features.supports_unknown_bits())
 195                         }
 196                 }
 197         }
 198
 199         fn handle_channel_announcement(&self, msg: &msgs::ChannelAnnouncement) -> Result<bool, HandleError> {
 200                 let msg_hash = Message::from_slice(&Sha256dHash::from_data(&msg.contents.encode()[..])[..]).unwrap();
 201                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.node_signature_1, &msg.contents.node_id_1);
 202                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.node_signature_2, &msg.contents.node_id_2);
 203                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.bitcoin_signature_1, &msg.contents.bitcoin_key_1);
 204                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.bitcoin_signature_2, &msg.contents.bitcoin_key_2);
 205
 206                 if msg.contents.features.requires_unknown_bits() {
 207                         panic!("Unknown-required-features ChannelAnnouncements should never deserialize!");
 208                 }
 209
 210                 match self.chain_monitor.get_chain_utxo(msg.contents.chain_hash, msg.contents.short_channel_id) {
 211                         Ok((script_pubkey, _value)) => {
 212                                 //TODO: Check if script_pubkey matches bitcoin_key_1 and bitcoin_key_2
 213                         },
 214                         Err(ChainError::NotSupported) => {
 215                                 // Tenatively accept, potentially exposing us to DoS attacks
 216                         },
 217                         Err(ChainError::NotWatched) => {
 218                                 return Err(HandleError{err: "Channel announced on an unknown chain", action: Some(ErrorAction::IgnoreError)});
 219                         },
 220                         Err(ChainError::UnknownTx) => {
 221                                 return Err(HandleError{err: "Channel announced without corresponding UTXO entry", action: Some(ErrorAction::IgnoreError)});
 222                         },
 223                 }
 224
 225                 let mut network = self.network_map.write().unwrap();
 226
 227                 match network.channels.entry(NetworkMap::get_key(msg.contents.short_channel_id, msg.contents.chain_hash)) {
 228                         Entry::Occupied(_) => {
 229                                 //TODO: because asking the blockchain if short_channel_id is valid is only optional
 230                                 //in the blockchain API, we need to handle it smartly here, though its unclear
 231                                 //exactly how...
 232                                 return Err(HandleError{err: "Already have knowledge of channel", action: Some(ErrorAction::IgnoreError)})
 233                         },
 234                         Entry::Vacant(entry) => {
 235                                 entry.insert(ChannelInfo {
 236                                         features: msg.contents.features.clone(),
 237                                         one_to_two: DirectionalChannelInfo {
 238                                                 src_node_id: msg.contents.node_id_1.clone(),
 239                                                 last_update: 0,
 240                                                 enabled: false,
 241                                                 cltv_expiry_delta: u16::max_value(),
 242                                                 htlc_minimum_msat: u64::max_value(),
 243                                                 fee_base_msat: u32::max_value(),
 244                                                 fee_proportional_millionths: u32::max_value(),
 245                                         },
 246                                         two_to_one: DirectionalChannelInfo {
 247                                                 src_node_id: msg.contents.node_id_2.clone(),
 248                                                 last_update: 0,
 249                                                 enabled: false,
 250                                                 cltv_expiry_delta: u16::max_value(),
 251                                                 htlc_minimum_msat: u64::max_value(),
 252                                                 fee_base_msat: u32::max_value(),
 253                                                 fee_proportional_millionths: u32::max_value(),
 254                                         }
 255                                 });
 256                         }
 257                 };
 258
 259                 macro_rules! add_channel_to_node {
 260                         ( $node_id: expr ) => {
 261                                 match network.nodes.entry($node_id) {
 262                                         Entry::Occupied(node_entry) => {
 263                                                 node_entry.into_mut().channels.push(NetworkMap::get_key(msg.contents.short_channel_id, msg.contents.chain_hash));
 264                                         },
 265                                         Entry::Vacant(node_entry) => {
 266                                                 node_entry.insert(NodeInfo {
 267                                                         channels: vec!(NetworkMap::get_key(msg.contents.short_channel_id, msg.contents.chain_hash)),
 268                                                         lowest_inbound_channel_fee_base_msat: u32::max_value(),
 269                                                         lowest_inbound_channel_fee_proportional_millionths: u32::max_value(),
 270                                                         features: GlobalFeatures::new(),
 271                                                         last_update: 0,
 272                                                         rgb: [0; 3],
 273                                                         alias: [0; 32],
 274                                                         addresses: Vec::new(),
 275                                                 });
 276                                         }
 277                                 }
 278                         };
 279                 }
 280
 281                 add_channel_to_node!(msg.contents.node_id_1);
 282                 add_channel_to_node!(msg.contents.node_id_2);
 283
 284                 Ok(msg.contents.excess_data.is_empty() && !msg.contents.features.supports_unknown_bits())
 285         }
 286
 287         fn handle_htlc_fail_channel_update(&self, update: &msgs::HTLCFailChannelUpdate) {
 288                 match update {
 289                         &msgs::HTLCFailChannelUpdate::ChannelUpdateMessage { ref msg } => {
 290                                 let _ = self.handle_channel_update(msg);
 291                         },
 292                         &msgs::HTLCFailChannelUpdate::ChannelClosed { ref short_channel_id } => {
 293                                 let mut network = self.network_map.write().unwrap();
 294                                 if let Some(chan) = network.channels.remove(short_channel_id) {
 295                                         network.nodes.get_mut(&chan.one_to_two.src_node_id).unwrap().channels.retain(|chan_id| {
 296                                                 chan_id != NetworkMap::get_short_id(chan_id)
 297                                         });
 298                                         network.nodes.get_mut(&chan.two_to_one.src_node_id).unwrap().channels.retain(|chan_id| {
 299                                                 chan_id != NetworkMap::get_short_id(chan_id)
 300                                         });
 301                                 }
 302                         },
 303                 }
 304         }
 305
 306         fn handle_channel_update(&self, msg: &msgs::ChannelUpdate) -> Result<bool, HandleError> {
 307                 let mut network = self.network_map.write().unwrap();
 308                 let dest_node_id;
 309                 let chan_enabled = msg.contents.flags & (1 << 1) != (1 << 1);
 310                 let chan_was_enabled;
 311
 312                 match network.channels.get_mut(&NetworkMap::get_key(msg.contents.short_channel_id, msg.contents.chain_hash)) {
 313                         None => return Err(HandleError{err: "Couldn't find channel for update", action: Some(ErrorAction::IgnoreError)}),
 314                         Some(channel) => {
 315                                 macro_rules! maybe_update_channel_info {
 316                                         ( $target: expr) => {
 317                                                 if $target.last_update >= msg.contents.timestamp {
 318                                                         return Err(HandleError{err: "Update older than last processed update", action: Some(ErrorAction::IgnoreError)});
 319                                                 }
 320                                                 chan_was_enabled = $target.enabled;
 321                                                 $target.last_update = msg.contents.timestamp;
 322                                                 $target.enabled = chan_enabled;
 323                                                 $target.cltv_expiry_delta = msg.contents.cltv_expiry_delta;
 324                                                 $target.htlc_minimum_msat = msg.contents.htlc_minimum_msat;
 325                                                 $target.fee_base_msat = msg.contents.fee_base_msat;
 326                                                 $target.fee_proportional_millionths = msg.contents.fee_proportional_millionths;
 327                                         }
 328                                 }
 329
 330                                 let msg_hash = Message::from_slice(&Sha256dHash::from_data(&msg.contents.encode()[..])[..]).unwrap();
 331                                 if msg.contents.flags & 1 == 1 {
 332                                         dest_node_id = channel.one_to_two.src_node_id.clone();
 333                                         secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.signature, &channel.two_to_one.src_node_id);
 334                                         maybe_update_channel_info!(channel.two_to_one);
 335                                 } else {
 336                                         dest_node_id = channel.two_to_one.src_node_id.clone();
 337                                         secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.signature, &channel.one_to_two.src_node_id);
 338                                         maybe_update_channel_info!(channel.one_to_two);
 339                                 }
 340                         }
 341                 }
 342
 343                 if chan_enabled {
 344                         let node = network.nodes.get_mut(&dest_node_id).unwrap();
 345                         node.lowest_inbound_channel_fee_base_msat = cmp::min(node.lowest_inbound_channel_fee_base_msat, msg.contents.fee_base_msat);
 346                         node.lowest_inbound_channel_fee_proportional_millionths = cmp::min(node.lowest_inbound_channel_fee_proportional_millionths, msg.contents.fee_proportional_millionths);
 347                 } else if chan_was_enabled {
 348                         let mut lowest_inbound_channel_fee_base_msat = u32::max_value();
 349                         let mut lowest_inbound_channel_fee_proportional_millionths = u32::max_value();
 350
 351                         {
 352                                 let node = network.nodes.get(&dest_node_id).unwrap();
 353
 354                                 for chan_id in node.channels.iter() {
 355                                         let chan = network.channels.get(chan_id).unwrap();
 356                                         if chan.one_to_two.src_node_id == dest_node_id {
 357                                                 lowest_inbound_channel_fee_base_msat = cmp::min(lowest_inbound_channel_fee_base_msat, chan.two_to_one.fee_base_msat);
 358                                                 lowest_inbound_channel_fee_proportional_millionths = cmp::min(lowest_inbound_channel_fee_proportional_millionths, chan.two_to_one.fee_proportional_millionths);
 359                                         } else {
 360                                                 lowest_inbound_channel_fee_base_msat = cmp::min(lowest_inbound_channel_fee_base_msat, chan.one_to_two.fee_base_msat);
 361                                                 lowest_inbound_channel_fee_proportional_millionths = cmp::min(lowest_inbound_channel_fee_proportional_millionths, chan.one_to_two.fee_proportional_millionths);
 362                                         }
 363                                 }
 364                         }
 365
 366                         //TODO: satisfy the borrow-checker without a double-map-lookup :(
 367                         let mut_node = network.nodes.get_mut(&dest_node_id).unwrap();
 368                         mut_node.lowest_inbound_channel_fee_base_msat = lowest_inbound_channel_fee_base_msat;
 369                         mut_node.lowest_inbound_channel_fee_proportional_millionths = lowest_inbound_channel_fee_proportional_millionths;
 370                 }
 371
 372                 Ok(msg.contents.excess_data.is_empty())
 373         }
 374 }
 375
 376 #[derive(Eq, PartialEq)]
 377 struct RouteGraphNode {
 378         pubkey: PublicKey,
 379         lowest_fee_to_peer_through_node: u64,
 380         lowest_fee_to_node: u64,
 381 }
 382
 383 impl cmp::Ord for RouteGraphNode {
 384         fn cmp(&self, other: &RouteGraphNode) -> cmp::Ordering {
 385                 other.lowest_fee_to_peer_through_node.cmp(&self.lowest_fee_to_peer_through_node)
 386                         .then_with(|| other.pubkey.serialize().cmp(&self.pubkey.serialize()))
 387         }
 388 }
 389
 390 impl cmp::PartialOrd for RouteGraphNode {
 391         fn partial_cmp(&self, other: &RouteGraphNode) -> Option<cmp::Ordering> {
 392                 Some(self.cmp(other))
 393         }
 394 }
 395
 396 struct DummyDirectionalChannelInfo {
 397         src_node_id: PublicKey,
 398         cltv_expiry_delta: u32,
 399         htlc_minimum_msat: u64,
 400         fee_base_msat: u32,
 401         fee_proportional_millionths: u32,
 402 }
 403
 404 impl Router {
 405         pub fn new(our_pubkey: PublicKey, chain_monitor: Arc<ChainWatchInterface>, logger: Arc<Logger>) -> Router {
 406                 let mut nodes = HashMap::new();
 407                 nodes.insert(our_pubkey.clone(), NodeInfo {
 408                         channels: Vec::new(),
 409                         lowest_inbound_channel_fee_base_msat: u32::max_value(),
 410                         lowest_inbound_channel_fee_proportional_millionths: u32::max_value(),
 411                         features: GlobalFeatures::new(),
 412                         last_update: 0,
 413                         rgb: [0; 3],
 414                         alias: [0; 32],
 415                         addresses: Vec::new(),
 416                 });
 417                 Router {
 418                         secp_ctx: Secp256k1::verification_only(),
 419                         network_map: RwLock::new(NetworkMap {
 420                                 channels: HashMap::new(),
 421                                 our_node_id: our_pubkey,
 422                                 nodes: nodes,
 423                         }),
 424                         chain_monitor,
 425                         logger,
 426                 }
 427         }
 428
 429         /// Dumps the entire network view of this Router to the logger provided in the constructor at
 430         /// level Trace
 431         pub fn trace_state(&self) {
 432                 log_trace!(self, "{}", self.network_map.read().unwrap());
 433         }
 434
 435         /// Get network addresses by node id
 436         pub fn get_addresses(&self, pubkey: &PublicKey) -> Option<Vec<NetAddress>> {
 437                 let network = self.network_map.read().unwrap();
 438                 network.nodes.get(pubkey).map(|n| n.addresses.clone())
 439         }
 440
 441         /// Marks a node as having failed a route. This will avoid re-using the node in routes for now,
 442         /// with an expotnential decay in node "badness". Note that there is deliberately no
 443         /// mark_channel_bad as a node may simply lie and suggest that an upstream channel from it is
 444         /// what failed the route and not the node itself. Instead, setting the blamed_upstream_node
 445         /// boolean will reduce the penalty, returning the node to usability faster. If the node is
 446         /// behaving correctly, it will disable the failing channel and we will use it again next time.
 447         pub fn mark_node_bad(&self, _node_id: &PublicKey, _blamed_upstream_node: bool) {
 448                 unimplemented!();
 449         }
 450
 451         /// Gets a route from us to the given target node.
 452         /// Extra routing hops between known nodes and the target will be used if they are included in
 453         /// last_hops.
 454         /// If some channels aren't announced, it may be useful to fill in a first_hops with the
 455         /// results from a local ChannelManager::list_usable_channels() call. If it is filled in, our
 456         /// (this Router's) view of our local channels will be ignored, and only those in first_hops
 457         /// will be used. Panics if first_hops contains channels without short_channel_ids
 458         /// (ChannelManager::list_usable_channels will never include such channels).
 459         /// The fees on channels from us to next-hops are ignored (as they are assumed to all be
 460         /// equal), however the enabled/disabled bit on such channels as well as the htlc_minimum_msat
 461         /// *is* checked as they may change based on the receiving node.
 462         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> {
 463                 // TODO: Obviously *only* using total fee cost sucks. We should consider weighting by
 464                 // uptime/success in using a node in the past.
 465                 let network = self.network_map.read().unwrap();
 466
 467                 if *target == network.our_node_id {
 468                         return Err(HandleError{err: "Cannot generate a route to ourselves", action: None});
 469                 }
 470
 471                 if final_value_msat > 21_000_000 * 1_0000_0000 * 1000 {
 472                         return Err(HandleError{err: "Cannot generate a route of more value than all existing satoshis", action: None});
 473                 }
 474
 475                 // We do a dest-to-source Dijkstra's sorting by each node's distance from the destination
 476                 // plus the minimum per-HTLC fee to get from it to another node (aka "shitty A*").
 477                 // TODO: There are a few tweaks we could do, including possibly pre-calculating more stuff
 478                 // to use as the A* heuristic beyond just the cost to get one node further than the current
 479                 // one.
 480
 481                 let dummy_directional_info = DummyDirectionalChannelInfo { // used for first_hops routes
 482                         src_node_id: network.our_node_id.clone(),
 483                         cltv_expiry_delta: 0,
 484                         htlc_minimum_msat: 0,
 485                         fee_base_msat: 0,
 486                         fee_proportional_millionths: 0,
 487                 };
 488
 489                 let mut targets = BinaryHeap::new(); //TODO: Do we care about switching to eg Fibbonaci heap?
 490                 let mut dist = HashMap::with_capacity(network.nodes.len());
 491
 492                 let mut first_hop_targets = HashMap::with_capacity(if first_hops.is_some() { first_hops.as_ref().unwrap().len() } else { 0 });
 493                 if let Some(hops) = first_hops {
 494                         for chan in hops {
 495                                 let short_channel_id = chan.short_channel_id.expect("first_hops should be filled in with usable channels, not pending ones");
 496                                 if chan.remote_network_id == *target {
 497                                         return Ok(Route {
 498                                                 hops: vec![RouteHop {
 499                                                         pubkey: chan.remote_network_id,
 500                                                         short_channel_id,
 501                                                         fee_msat: final_value_msat,
 502                                                         cltv_expiry_delta: final_cltv,
 503                                                 }],
 504                                         });
 505                                 }
 506                                 first_hop_targets.insert(chan.remote_network_id, short_channel_id);
 507                         }
 508                         if first_hop_targets.is_empty() {
 509                                 return Err(HandleError{err: "Cannot route when there are no outbound routes away from us", action: None});
 510                         }
 511                 }
 512
 513                 macro_rules! add_entry {
 514                         // Adds entry which goes from the node pointed to by $directional_info to
 515                         // $dest_node_id over the channel with id $chan_id with fees described in
 516                         // $directional_info.
 517                         ( $chan_id: expr, $dest_node_id: expr, $directional_info: expr, $starting_fee_msat: expr ) => {
 518                                 //TODO: Explore simply adding fee to hit htlc_minimum_msat
 519                                 if $starting_fee_msat as u64 + final_value_msat > $directional_info.htlc_minimum_msat {
 520                                         let proportional_fee_millions = ($starting_fee_msat + final_value_msat).checked_mul($directional_info.fee_proportional_millionths as u64);
 521                                         if let Some(new_fee) = proportional_fee_millions.and_then(|part| {
 522                                                         ($directional_info.fee_base_msat as u64).checked_add(part / 1000000) })
 523                                         {
 524                                                 let mut total_fee = $starting_fee_msat as u64;
 525                                                 let hm_entry = dist.entry(&$directional_info.src_node_id);
 526                                                 let old_entry = hm_entry.or_insert_with(|| {
 527                                                         let node = network.nodes.get(&$directional_info.src_node_id).unwrap();
 528                                                         (u64::max_value(),
 529                                                                 node.lowest_inbound_channel_fee_base_msat,
 530                                                                 node.lowest_inbound_channel_fee_proportional_millionths,
 531                                                                 RouteHop {
 532                                                                         pubkey: $dest_node_id.clone(),
 533                                                                         short_channel_id: 0,
 534                                                                         fee_msat: 0,
 535                                                                         cltv_expiry_delta: 0,
 536                                                         })
 537                                                 });
 538                                                 if $directional_info.src_node_id != network.our_node_id {
 539                                                         // Ignore new_fee for channel-from-us as we assume all channels-from-us
 540                                                         // will have the same effective-fee
 541                                                         total_fee += new_fee;
 542                                                         if let Some(fee_inc) = final_value_msat.checked_add(total_fee).and_then(|inc| { (old_entry.2 as u64).checked_mul(inc) }) {
 543                                                                 total_fee += fee_inc / 1000000 + (old_entry.1 as u64);
 544                                                         } else {
 545                                                                 // max_value means we'll always fail the old_entry.0 > total_fee check
 546                                                                 total_fee = u64::max_value();
 547                                                         }
 548                                                 }
 549                                                 let new_graph_node = RouteGraphNode {
 550                                                         pubkey: $directional_info.src_node_id,
 551                                                         lowest_fee_to_peer_through_node: total_fee,
 552                                                         lowest_fee_to_node: $starting_fee_msat as u64 + new_fee,
 553                                                 };
 554                                                 if old_entry.0 > total_fee {
 555                                                         targets.push(new_graph_node);
 556                                                         old_entry.0 = total_fee;
 557                                                         old_entry.3 = RouteHop {
 558                                                                 pubkey: $dest_node_id.clone(),
 559                                                                 short_channel_id: $chan_id.clone(),
 560                                                                 fee_msat: new_fee, // This field is ignored on the last-hop anyway
 561                                                                 cltv_expiry_delta: $directional_info.cltv_expiry_delta as u32,
 562                                                         }
 563                                                 }
 564                                         }
 565                                 }
 566                         };
 567                 }
 568
 569                 macro_rules! add_entries_to_cheapest_to_target_node {
 570                         ( $node: expr, $node_id: expr, $fee_to_target_msat: expr ) => {
 571                                 if first_hops.is_some() {
 572                                         if let Some(first_hop) = first_hop_targets.get(&$node_id) {
 573                                                 add_entry!(first_hop, $node_id, dummy_directional_info, $fee_to_target_msat);
 574                                         }
 575                                 }
 576
 577                                 for chan_id in $node.channels.iter() {
 578                                         let chan = network.channels.get(chan_id).unwrap();
 579                                         if chan.one_to_two.src_node_id == *$node_id {
 580                                                 // ie $node is one, ie next hop in A* is two, via the two_to_one channel
 581                                                 if first_hops.is_none() || chan.two_to_one.src_node_id != network.our_node_id {
 582                                                         if chan.two_to_one.enabled {
 583                                                                 add_entry!(chan_id, chan.one_to_two.src_node_id, chan.two_to_one, $fee_to_target_msat);
 584                                                         }
 585                                                 }
 586                                         } else {
 587                                                 if first_hops.is_none() || chan.one_to_two.src_node_id != network.our_node_id {
 588                                                         if chan.one_to_two.enabled {
 589                                                                 add_entry!(chan_id, chan.two_to_one.src_node_id, chan.one_to_two, $fee_to_target_msat);
 590                                                         }
 591                                                 }
 592                                         }
 593                                 }
 594                         };
 595                 }
 596
 597                 match network.nodes.get(target) {
 598                         None => {},
 599                         Some(node) => {
 600                                 add_entries_to_cheapest_to_target_node!(node, target, 0);
 601                         },
 602                 }
 603
 604                 for hop in last_hops.iter() {
 605                         if first_hops.is_none() || hop.src_node_id != network.our_node_id { // first_hop overrules last_hops
 606                                 if network.nodes.get(&hop.src_node_id).is_some() {
 607                                         if first_hops.is_some() {
 608                                                 if let Some(first_hop) = first_hop_targets.get(&hop.src_node_id) {
 609                                                         add_entry!(first_hop, hop.src_node_id, dummy_directional_info, 0);
 610                                                 }
 611                                         }
 612                                         add_entry!(hop.short_channel_id, target, hop, 0);
 613                                 }
 614                         }
 615                 }
 616
 617                 while let Some(RouteGraphNode { pubkey, lowest_fee_to_node, .. }) = targets.pop() {
 618                         if pubkey == network.our_node_id {
 619                                 let mut res = vec!(dist.remove(&network.our_node_id).unwrap().3);
 620                                 while res.last().unwrap().pubkey != *target {
 621                                         let new_entry = match dist.remove(&res.last().unwrap().pubkey) {
 622                                                 Some(hop) => hop.3,
 623                                                 None => return Err(HandleError{err: "Failed to find a non-fee-overflowing path to the given destination", action: None}),
 624                                         };
 625                                         res.last_mut().unwrap().fee_msat = new_entry.fee_msat;
 626                                         res.last_mut().unwrap().cltv_expiry_delta = new_entry.cltv_expiry_delta;
 627                                         res.push(new_entry);
 628                                 }
 629                                 res.last_mut().unwrap().fee_msat = final_value_msat;
 630                                 res.last_mut().unwrap().cltv_expiry_delta = final_cltv;
 631                                 let route = Route { hops: res };
 632                                 log_trace!(self, "Got route: {}", log_route!(route));
 633                                 return Ok(route);
 634                         }
 635
 636                         match network.nodes.get(&pubkey) {
 637                                 None => {},
 638                                 Some(node) => {
 639                                         add_entries_to_cheapest_to_target_node!(node, &pubkey, lowest_fee_to_node);
 640                                 },
 641                         }
 642                 }
 643
 644                 Err(HandleError{err: "Failed to find a path to the given destination", action: None})
 645         }
 646 }
 647
 648 #[cfg(test)]
 649 mod tests {
 650         use chain::chaininterface;
 651         use ln::channelmanager;
 652         use ln::router::{Router,NodeInfo,NetworkMap,ChannelInfo,DirectionalChannelInfo,RouteHint};
 653         use ln::msgs::GlobalFeatures;
 654         use util::test_utils;
 655         use util::logger::Logger;
 656
 657         use bitcoin::util::hash::Sha256dHash;
 658         use bitcoin::network::constants::Network;
 659
 660         use hex;
 661
 662         use secp256k1::key::{PublicKey,SecretKey};
 663         use secp256k1::Secp256k1;
 664
 665         use std::sync::Arc;
 666
 667         #[test]
 668         fn route_test() {
 669                 let secp_ctx = Secp256k1::new();
 670                 let our_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap());
 671                 let logger: Arc<Logger> = Arc::new(test_utils::TestLogger::new());
 672                 let chain_monitor = Arc::new(chaininterface::ChainWatchInterfaceUtil::new(Network::Testnet, Arc::clone(&logger)));
 673                 let router = Router::new(our_id, chain_monitor, Arc::clone(&logger));
 674
 675                 // Build network from our_id to node8:
 676                 //
 677                 //        -1(1)2-  node1  -1(3)2-
 678                 //       /                       \
 679                 // our_id -1(12)2- node8 -1(13)2--- node3
 680                 //       \                       /
 681                 //        -1(2)2-  node2  -1(4)2-
 682                 //
 683                 //
 684                 // chan1  1-to-2: disabled
 685                 // chan1  2-to-1: enabled, 0 fee
 686                 //
 687                 // chan2  1-to-2: enabled, ignored fee
 688                 // chan2  2-to-1: enabled, 0 fee
 689                 //
 690                 // chan3  1-to-2: enabled, 0 fee
 691                 // chan3  2-to-1: enabled, 100 msat fee
 692                 //
 693                 // chan4  1-to-2: enabled, 100% fee
 694                 // chan4  2-to-1: enabled, 0 fee
 695                 //
 696                 // chan12 1-to-2: enabled, ignored fee
 697                 // chan12 2-to-1: enabled, 0 fee
 698                 //
 699                 // chan13 1-to-2: enabled, 200% fee
 700                 // chan13 2-to-1: enabled, 0 fee
 701                 //
 702                 //
 703                 //       -1(5)2- node4 -1(8)2--
 704                 //       |         2          |
 705                 //       |       (11)         |
 706                 //      /          1           \
 707                 // node3--1(6)2- node5 -1(9)2--- node7 (not in global route map)
 708                 //      \                      /
 709                 //       -1(7)2- node6 -1(10)2-
 710                 //
 711                 // chan5  1-to-2: enabled, 100 msat fee
 712                 // chan5  2-to-1: enabled, 0 fee
 713                 //
 714                 // chan6  1-to-2: enabled, 0 fee
 715                 // chan6  2-to-1: enabled, 0 fee
 716                 //
 717                 // chan7  1-to-2: enabled, 100% fee
 718                 // chan7  2-to-1: enabled, 0 fee
 719                 //
 720                 // chan8  1-to-2: enabled, variable fee (0 then 1000 msat)
 721                 // chan8  2-to-1: enabled, 0 fee
 722                 //
 723                 // chan9  1-to-2: enabled, 1001 msat fee
 724                 // chan9  2-to-1: enabled, 0 fee
 725                 //
 726                 // chan10 1-to-2: enabled, 0 fee
 727                 // chan10 2-to-1: enabled, 0 fee
 728                 //
 729                 // chan11 1-to-2: enabled, 0 fee
 730                 // chan11 2-to-1: enabled, 0 fee
 731
 732                 let node1 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &hex::decode("0202020202020202020202020202020202020202020202020202020202020202").unwrap()[..]).unwrap());
 733                 let node2 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &hex::decode("0303030303030303030303030303030303030303030303030303030303030303").unwrap()[..]).unwrap());
 734                 let node3 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &hex::decode("0404040404040404040404040404040404040404040404040404040404040404").unwrap()[..]).unwrap());
 735                 let node4 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &hex::decode("0505050505050505050505050505050505050505050505050505050505050505").unwrap()[..]).unwrap());
 736                 let node5 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &hex::decode("0606060606060606060606060606060606060606060606060606060606060606").unwrap()[..]).unwrap());
 737                 let node6 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &hex::decode("0707070707070707070707070707070707070707070707070707070707070707").unwrap()[..]).unwrap());
 738                 let node7 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &hex::decode("0808080808080808080808080808080808080808080808080808080808080808").unwrap()[..]).unwrap());
 739                 let node8 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &hex::decode("0909090909090909090909090909090909090909090909090909090909090909").unwrap()[..]).unwrap());
 740
 741                 let zero_hash = Sha256dHash::from_data(&[0; 32]);
 742
 743                 {
 744                         let mut network = router.network_map.write().unwrap();
 745
 746                         network.nodes.insert(node1.clone(), NodeInfo {
 747                                 channels: vec!(NetworkMap::get_key(1, zero_hash.clone()), NetworkMap::get_key(3, zero_hash.clone())),
 748                                 lowest_inbound_channel_fee_base_msat: 100,
 749                                 lowest_inbound_channel_fee_proportional_millionths: 0,
 750                                 features: GlobalFeatures::new(),
 751                                 last_update: 1,
 752                                 rgb: [0; 3],
 753                                 alias: [0; 32],
 754                                 addresses: Vec::new(),
 755                         });
 756                         network.channels.insert(NetworkMap::get_key(1, zero_hash.clone()), ChannelInfo {
 757                                 features: GlobalFeatures::new(),
 758                                 one_to_two: DirectionalChannelInfo {
 759                                         src_node_id: our_id.clone(),
 760                                         last_update: 0,
 761                                         enabled: false,
 762                                         cltv_expiry_delta: u16::max_value(), // This value should be ignored
 763                                         htlc_minimum_msat: 0,
 764                                         fee_base_msat: u32::max_value(), // This value should be ignored
 765                                         fee_proportional_millionths: u32::max_value(), // This value should be ignored
 766                                 }, two_to_one: DirectionalChannelInfo {
 767                                         src_node_id: node1.clone(),
 768                                         last_update: 0,
 769                                         enabled: true,
 770                                         cltv_expiry_delta: 0,
 771                                         htlc_minimum_msat: 0,
 772                                         fee_base_msat: 0,
 773                                         fee_proportional_millionths: 0,
 774                                 },
 775                         });
 776                         network.nodes.insert(node2.clone(), NodeInfo {
 777                                 channels: vec!(NetworkMap::get_key(2, zero_hash.clone()), NetworkMap::get_key(4, zero_hash.clone())),
 778                                 lowest_inbound_channel_fee_base_msat: 0,
 779                                 lowest_inbound_channel_fee_proportional_millionths: 0,
 780                                 features: GlobalFeatures::new(),
 781                                 last_update: 1,
 782                                 rgb: [0; 3],
 783                                 alias: [0; 32],
 784                                 addresses: Vec::new(),
 785                         });
 786                         network.channels.insert(NetworkMap::get_key(2, zero_hash.clone()), ChannelInfo {
 787                                 features: GlobalFeatures::new(),
 788                                 one_to_two: DirectionalChannelInfo {
 789                                         src_node_id: our_id.clone(),
 790                                         last_update: 0,
 791                                         enabled: true,
 792                                         cltv_expiry_delta: u16::max_value(), // This value should be ignored
 793                                         htlc_minimum_msat: 0,
 794                                         fee_base_msat: u32::max_value(), // This value should be ignored
 795                                         fee_proportional_millionths: u32::max_value(), // This value should be ignored
 796                                 }, two_to_one: DirectionalChannelInfo {
 797                                         src_node_id: node2.clone(),
 798                                         last_update: 0,
 799                                         enabled: true,
 800                                         cltv_expiry_delta: 0,
 801                                         htlc_minimum_msat: 0,
 802                                         fee_base_msat: 0,
 803                                         fee_proportional_millionths: 0,
 804                                 },
 805                         });
 806                         network.nodes.insert(node8.clone(), NodeInfo {
 807                                 channels: vec!(NetworkMap::get_key(12, zero_hash.clone()), NetworkMap::get_key(13, zero_hash.clone())),
 808                                 lowest_inbound_channel_fee_base_msat: 0,
 809                                 lowest_inbound_channel_fee_proportional_millionths: 0,
 810                                 features: GlobalFeatures::new(),
 811                                 last_update: 1,
 812                                 rgb: [0; 3],
 813                                 alias: [0; 32],
 814                                 addresses: Vec::new(),
 815                         });
 816                         network.channels.insert(NetworkMap::get_key(12, zero_hash.clone()), ChannelInfo {
 817                                 features: GlobalFeatures::new(),
 818                                 one_to_two: DirectionalChannelInfo {
 819                                         src_node_id: our_id.clone(),
 820                                         last_update: 0,
 821                                         enabled: true,
 822                                         cltv_expiry_delta: u16::max_value(), // This value should be ignored
 823                                         htlc_minimum_msat: 0,
 824                                         fee_base_msat: u32::max_value(), // This value should be ignored
 825                                         fee_proportional_millionths: u32::max_value(), // This value should be ignored
 826                                 }, two_to_one: DirectionalChannelInfo {
 827                                         src_node_id: node8.clone(),
 828                                         last_update: 0,
 829                                         enabled: true,
 830                                         cltv_expiry_delta: 0,
 831                                         htlc_minimum_msat: 0,
 832                                         fee_base_msat: 0,
 833                                         fee_proportional_millionths: 0,
 834                                 },
 835                         });
 836                         network.nodes.insert(node3.clone(), NodeInfo {
 837                                 channels: vec!(
 838                                         NetworkMap::get_key(3, zero_hash.clone()),
 839                                         NetworkMap::get_key(4, zero_hash.clone()),
 840                                         NetworkMap::get_key(13, zero_hash.clone()),
 841                                         NetworkMap::get_key(5, zero_hash.clone()),
 842                                         NetworkMap::get_key(6, zero_hash.clone()),
 843                                         NetworkMap::get_key(7, zero_hash.clone())),
 844                                 lowest_inbound_channel_fee_base_msat: 0,
 845                                 lowest_inbound_channel_fee_proportional_millionths: 0,
 846                                 features: GlobalFeatures::new(),
 847                                 last_update: 1,
 848                                 rgb: [0; 3],
 849                                 alias: [0; 32],
 850                                 addresses: Vec::new(),
 851                         });
 852                         network.channels.insert(NetworkMap::get_key(3, zero_hash.clone()), ChannelInfo {
 853                                 features: GlobalFeatures::new(),
 854                                 one_to_two: DirectionalChannelInfo {
 855                                         src_node_id: node1.clone(),
 856                                         last_update: 0,
 857                                         enabled: true,
 858                                         cltv_expiry_delta: (3 << 8) | 1,
 859                                         htlc_minimum_msat: 0,
 860                                         fee_base_msat: 0,
 861                                         fee_proportional_millionths: 0,
 862                                 }, two_to_one: DirectionalChannelInfo {
 863                                         src_node_id: node3.clone(),
 864                                         last_update: 0,
 865                                         enabled: true,
 866                                         cltv_expiry_delta: (3 << 8) | 2,
 867                                         htlc_minimum_msat: 0,
 868                                         fee_base_msat: 100,
 869                                         fee_proportional_millionths: 0,
 870                                 },
 871                         });
 872                         network.channels.insert(NetworkMap::get_key(4, zero_hash.clone()), ChannelInfo {
 873                                 features: GlobalFeatures::new(),
 874                                 one_to_two: DirectionalChannelInfo {
 875                                         src_node_id: node2.clone(),
 876                                         last_update: 0,
 877                                         enabled: true,
 878                                         cltv_expiry_delta: (4 << 8) | 1,
 879                                         htlc_minimum_msat: 0,
 880                                         fee_base_msat: 0,
 881                                         fee_proportional_millionths: 1000000,
 882                                 }, two_to_one: DirectionalChannelInfo {
 883                                         src_node_id: node3.clone(),
 884                                         last_update: 0,
 885                                         enabled: true,
 886                                         cltv_expiry_delta: (4 << 8) | 2,
 887                                         htlc_minimum_msat: 0,
 888                                         fee_base_msat: 0,
 889                                         fee_proportional_millionths: 0,
 890                                 },
 891                         });
 892                         network.channels.insert(NetworkMap::get_key(13, zero_hash.clone()), ChannelInfo {
 893                                 features: GlobalFeatures::new(),
 894                                 one_to_two: DirectionalChannelInfo {
 895                                         src_node_id: node8.clone(),
 896                                         last_update: 0,
 897                                         enabled: true,
 898                                         cltv_expiry_delta: (13 << 8) | 1,
 899                                         htlc_minimum_msat: 0,
 900                                         fee_base_msat: 0,
 901                                         fee_proportional_millionths: 2000000,
 902                                 }, two_to_one: DirectionalChannelInfo {
 903                                         src_node_id: node3.clone(),
 904                                         last_update: 0,
 905                                         enabled: true,
 906                                         cltv_expiry_delta: (13 << 8) | 2,
 907                                         htlc_minimum_msat: 0,
 908                                         fee_base_msat: 0,
 909                                         fee_proportional_millionths: 0,
 910                                 },
 911                         });
 912                         network.nodes.insert(node4.clone(), NodeInfo {
 913                                 channels: vec!(NetworkMap::get_key(5, zero_hash.clone()), NetworkMap::get_key(11, zero_hash.clone())),
 914                                 lowest_inbound_channel_fee_base_msat: 0,
 915                                 lowest_inbound_channel_fee_proportional_millionths: 0,
 916                                 features: GlobalFeatures::new(),
 917                                 last_update: 1,
 918                                 rgb: [0; 3],
 919                                 alias: [0; 32],
 920                                 addresses: Vec::new(),
 921                         });
 922                         network.channels.insert(NetworkMap::get_key(5, zero_hash.clone()), ChannelInfo {
 923                                 features: GlobalFeatures::new(),
 924                                 one_to_two: DirectionalChannelInfo {
 925                                         src_node_id: node3.clone(),
 926                                         last_update: 0,
 927                                         enabled: true,
 928                                         cltv_expiry_delta: (5 << 8) | 1,
 929                                         htlc_minimum_msat: 0,
 930                                         fee_base_msat: 100,
 931                                         fee_proportional_millionths: 0,
 932                                 }, two_to_one: DirectionalChannelInfo {
 933                                         src_node_id: node4.clone(),
 934                                         last_update: 0,
 935                                         enabled: true,
 936                                         cltv_expiry_delta: (5 << 8) | 2,
 937                                         htlc_minimum_msat: 0,
 938                                         fee_base_msat: 0,
 939                                         fee_proportional_millionths: 0,
 940                                 },
 941                         });
 942                         network.nodes.insert(node5.clone(), NodeInfo {
 943                                 channels: vec!(NetworkMap::get_key(6, zero_hash.clone()), NetworkMap::get_key(11, zero_hash.clone())),
 944                                 lowest_inbound_channel_fee_base_msat: 0,
 945                                 lowest_inbound_channel_fee_proportional_millionths: 0,
 946                                 features: GlobalFeatures::new(),
 947                                 last_update: 1,
 948                                 rgb: [0; 3],
 949                                 alias: [0; 32],
 950                                 addresses: Vec::new(),
 951                         });
 952                         network.channels.insert(NetworkMap::get_key(6, zero_hash.clone()), ChannelInfo {
 953                                 features: GlobalFeatures::new(),
 954                                 one_to_two: DirectionalChannelInfo {
 955                                         src_node_id: node3.clone(),
 956                                         last_update: 0,
 957                                         enabled: true,
 958                                         cltv_expiry_delta: (6 << 8) | 1,
 959                                         htlc_minimum_msat: 0,
 960                                         fee_base_msat: 0,
 961                                         fee_proportional_millionths: 0,
 962                                 }, two_to_one: DirectionalChannelInfo {
 963                                         src_node_id: node5.clone(),
 964                                         last_update: 0,
 965                                         enabled: true,
 966                                         cltv_expiry_delta: (6 << 8) | 2,
 967                                         htlc_minimum_msat: 0,
 968                                         fee_base_msat: 0,
 969                                         fee_proportional_millionths: 0,
 970                                 },
 971                         });
 972                         network.channels.insert(NetworkMap::get_key(11, zero_hash.clone()), ChannelInfo {
 973                                 features: GlobalFeatures::new(),
 974                                 one_to_two: DirectionalChannelInfo {
 975                                         src_node_id: node5.clone(),
 976                                         last_update: 0,
 977                                         enabled: true,
 978                                         cltv_expiry_delta: (11 << 8) | 1,
 979                                         htlc_minimum_msat: 0,
 980                                         fee_base_msat: 0,
 981                                         fee_proportional_millionths: 0,
 982                                 }, two_to_one: DirectionalChannelInfo {
 983                                         src_node_id: node4.clone(),
 984                                         last_update: 0,
 985                                         enabled: true,
 986                                         cltv_expiry_delta: (11 << 8) | 2,
 987                                         htlc_minimum_msat: 0,
 988                                         fee_base_msat: 0,
 989                                         fee_proportional_millionths: 0,
 990                                 },
 991                         });
 992                         network.nodes.insert(node6.clone(), NodeInfo {
 993                                 channels: vec!(NetworkMap::get_key(7, zero_hash.clone())),
 994                                 lowest_inbound_channel_fee_base_msat: 0,
 995                                 lowest_inbound_channel_fee_proportional_millionths: 0,
 996                                 features: GlobalFeatures::new(),
 997                                 last_update: 1,
 998                                 rgb: [0; 3],
 999                                 alias: [0; 32],
1000                                 addresses: Vec::new(),
1001                         });
1002                         network.channels.insert(NetworkMap::get_key(7, zero_hash.clone()), ChannelInfo {
1003                                 features: GlobalFeatures::new(),
1004                                 one_to_two: DirectionalChannelInfo {
1005                                         src_node_id: node3.clone(),
1006                                         last_update: 0,
1007                                         enabled: true,
1008                                         cltv_expiry_delta: (7 << 8) | 1,
1009                                         htlc_minimum_msat: 0,
1010                                         fee_base_msat: 0,
1011                                         fee_proportional_millionths: 1000000,
1012                                 }, two_to_one: DirectionalChannelInfo {
1013                                         src_node_id: node6.clone(),
1014                                         last_update: 0,
1015                                         enabled: true,
1016                                         cltv_expiry_delta: (7 << 8) | 2,
1017                                         htlc_minimum_msat: 0,
1018                                         fee_base_msat: 0,
1019                                         fee_proportional_millionths: 0,
1020                                 },
1021                         });
1022                 }
1023
1024                 { // Simple route to 3 via 2
1025                         let route = router.get_route(&node3, None, &Vec::new(), 100, 42).unwrap();
1026                         assert_eq!(route.hops.len(), 2);
1027
1028                         assert_eq!(route.hops[0].pubkey, node2);
1029                         assert_eq!(route.hops[0].short_channel_id, 2);
1030                         assert_eq!(route.hops[0].fee_msat, 100);
1031                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1032
1033                         assert_eq!(route.hops[1].pubkey, node3);
1034                         assert_eq!(route.hops[1].short_channel_id, 4);
1035                         assert_eq!(route.hops[1].fee_msat, 100);
1036                         assert_eq!(route.hops[1].cltv_expiry_delta, 42);
1037                 }
1038
1039                 { // Route to 1 via 2 and 3 because our channel to 1 is disabled
1040                         let route = router.get_route(&node1, None, &Vec::new(), 100, 42).unwrap();
1041                         assert_eq!(route.hops.len(), 3);
1042
1043                         assert_eq!(route.hops[0].pubkey, node2);
1044                         assert_eq!(route.hops[0].short_channel_id, 2);
1045                         assert_eq!(route.hops[0].fee_msat, 200);
1046                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1047
1048                         assert_eq!(route.hops[1].pubkey, node3);
1049                         assert_eq!(route.hops[1].short_channel_id, 4);
1050                         assert_eq!(route.hops[1].fee_msat, 100);
1051                         assert_eq!(route.hops[1].cltv_expiry_delta, (3 << 8) | 2);
1052
1053                         assert_eq!(route.hops[2].pubkey, node1);
1054                         assert_eq!(route.hops[2].short_channel_id, 3);
1055                         assert_eq!(route.hops[2].fee_msat, 100);
1056                         assert_eq!(route.hops[2].cltv_expiry_delta, 42);
1057                 }
1058
1059                 { // If we specify a channel to node8, that overrides our local channel view and that gets used
1060                         let our_chans = vec![channelmanager::ChannelDetails {
1061                                 channel_id: [0; 32],
1062                                 short_channel_id: Some(42),
1063                                 remote_network_id: node8.clone(),
1064                                 channel_value_satoshis: 0,
1065                                 user_id: 0,
1066                         }];
1067                         let route = router.get_route(&node3, Some(&our_chans), &Vec::new(), 100, 42).unwrap();
1068                         assert_eq!(route.hops.len(), 2);
1069
1070                         assert_eq!(route.hops[0].pubkey, node8);
1071                         assert_eq!(route.hops[0].short_channel_id, 42);
1072                         assert_eq!(route.hops[0].fee_msat, 200);
1073                         assert_eq!(route.hops[0].cltv_expiry_delta, (13 << 8) | 1);
1074
1075                         assert_eq!(route.hops[1].pubkey, node3);
1076                         assert_eq!(route.hops[1].short_channel_id, 13);
1077                         assert_eq!(route.hops[1].fee_msat, 100);
1078                         assert_eq!(route.hops[1].cltv_expiry_delta, 42);
1079                 }
1080
1081                 let mut last_hops = vec!(RouteHint {
1082                                 src_node_id: node4.clone(),
1083                                 short_channel_id: 8,
1084                                 fee_base_msat: 0,
1085                                 fee_proportional_millionths: 0,
1086                                 cltv_expiry_delta: (8 << 8) | 1,
1087                                 htlc_minimum_msat: 0,
1088                         }, RouteHint {
1089                                 src_node_id: node5.clone(),
1090                                 short_channel_id: 9,
1091                                 fee_base_msat: 1001,
1092                                 fee_proportional_millionths: 0,
1093                                 cltv_expiry_delta: (9 << 8) | 1,
1094                                 htlc_minimum_msat: 0,
1095                         }, RouteHint {
1096                                 src_node_id: node6.clone(),
1097                                 short_channel_id: 10,
1098                                 fee_base_msat: 0,
1099                                 fee_proportional_millionths: 0,
1100                                 cltv_expiry_delta: (10 << 8) | 1,
1101                                 htlc_minimum_msat: 0,
1102                         });
1103
1104                 { // Simple test across 2, 3, 5, and 4 via a last_hop channel
1105                         let route = router.get_route(&node7, None, &last_hops, 100, 42).unwrap();
1106                         assert_eq!(route.hops.len(), 5);
1107
1108                         assert_eq!(route.hops[0].pubkey, node2);
1109                         assert_eq!(route.hops[0].short_channel_id, 2);
1110                         assert_eq!(route.hops[0].fee_msat, 100);
1111                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1112
1113                         assert_eq!(route.hops[1].pubkey, node3);
1114                         assert_eq!(route.hops[1].short_channel_id, 4);
1115                         assert_eq!(route.hops[1].fee_msat, 0);
1116                         assert_eq!(route.hops[1].cltv_expiry_delta, (6 << 8) | 1);
1117
1118                         assert_eq!(route.hops[2].pubkey, node5);
1119                         assert_eq!(route.hops[2].short_channel_id, 6);
1120                         assert_eq!(route.hops[2].fee_msat, 0);
1121                         assert_eq!(route.hops[2].cltv_expiry_delta, (11 << 8) | 1);
1122
1123                         assert_eq!(route.hops[3].pubkey, node4);
1124                         assert_eq!(route.hops[3].short_channel_id, 11);
1125                         assert_eq!(route.hops[3].fee_msat, 0);
1126                         assert_eq!(route.hops[3].cltv_expiry_delta, (8 << 8) | 1);
1127
1128                         assert_eq!(route.hops[4].pubkey, node7);
1129                         assert_eq!(route.hops[4].short_channel_id, 8);
1130                         assert_eq!(route.hops[4].fee_msat, 100);
1131                         assert_eq!(route.hops[4].cltv_expiry_delta, 42);
1132                 }
1133
1134                 { // Simple test with outbound channel to 4 to test that last_hops and first_hops connect
1135                         let our_chans = vec![channelmanager::ChannelDetails {
1136                                 channel_id: [0; 32],
1137                                 short_channel_id: Some(42),
1138                                 remote_network_id: node4.clone(),
1139                                 channel_value_satoshis: 0,
1140                                 user_id: 0,
1141                         }];
1142                         let route = router.get_route(&node7, Some(&our_chans), &last_hops, 100, 42).unwrap();
1143                         assert_eq!(route.hops.len(), 2);
1144
1145                         assert_eq!(route.hops[0].pubkey, node4);
1146                         assert_eq!(route.hops[0].short_channel_id, 42);
1147                         assert_eq!(route.hops[0].fee_msat, 0);
1148                         assert_eq!(route.hops[0].cltv_expiry_delta, (8 << 8) | 1);
1149
1150                         assert_eq!(route.hops[1].pubkey, node7);
1151                         assert_eq!(route.hops[1].short_channel_id, 8);
1152                         assert_eq!(route.hops[1].fee_msat, 100);
1153                         assert_eq!(route.hops[1].cltv_expiry_delta, 42);
1154                 }
1155
1156                 last_hops[0].fee_base_msat = 1000;
1157
1158                 { // Revert to via 6 as the fee on 8 goes up
1159                         let route = router.get_route(&node7, None, &last_hops, 100, 42).unwrap();
1160                         assert_eq!(route.hops.len(), 4);
1161
1162                         assert_eq!(route.hops[0].pubkey, node2);
1163                         assert_eq!(route.hops[0].short_channel_id, 2);
1164                         assert_eq!(route.hops[0].fee_msat, 200); // fee increased as its % of value transferred across node
1165                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1166
1167                         assert_eq!(route.hops[1].pubkey, node3);
1168                         assert_eq!(route.hops[1].short_channel_id, 4);
1169                         assert_eq!(route.hops[1].fee_msat, 100);
1170                         assert_eq!(route.hops[1].cltv_expiry_delta, (7 << 8) | 1);
1171
1172                         assert_eq!(route.hops[2].pubkey, node6);
1173                         assert_eq!(route.hops[2].short_channel_id, 7);
1174                         assert_eq!(route.hops[2].fee_msat, 0);
1175                         assert_eq!(route.hops[2].cltv_expiry_delta, (10 << 8) | 1);
1176
1177                         assert_eq!(route.hops[3].pubkey, node7);
1178                         assert_eq!(route.hops[3].short_channel_id, 10);
1179                         assert_eq!(route.hops[3].fee_msat, 100);
1180                         assert_eq!(route.hops[3].cltv_expiry_delta, 42);
1181                 }
1182
1183                 { // ...but still use 8 for larger payments as 6 has a variable feerate
1184                         let route = router.get_route(&node7, None, &last_hops, 2000, 42).unwrap();
1185                         assert_eq!(route.hops.len(), 5);
1186
1187                         assert_eq!(route.hops[0].pubkey, node2);
1188                         assert_eq!(route.hops[0].short_channel_id, 2);
1189                         assert_eq!(route.hops[0].fee_msat, 3000);
1190                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1191
1192                         assert_eq!(route.hops[1].pubkey, node3);
1193                         assert_eq!(route.hops[1].short_channel_id, 4);
1194                         assert_eq!(route.hops[1].fee_msat, 0);
1195                         assert_eq!(route.hops[1].cltv_expiry_delta, (6 << 8) | 1);
1196
1197                         assert_eq!(route.hops[2].pubkey, node5);
1198                         assert_eq!(route.hops[2].short_channel_id, 6);
1199                         assert_eq!(route.hops[2].fee_msat, 0);
1200                         assert_eq!(route.hops[2].cltv_expiry_delta, (11 << 8) | 1);
1201
1202                         assert_eq!(route.hops[3].pubkey, node4);
1203                         assert_eq!(route.hops[3].short_channel_id, 11);
1204                         assert_eq!(route.hops[3].fee_msat, 1000);
1205                         assert_eq!(route.hops[3].cltv_expiry_delta, (8 << 8) | 1);
1206
1207                         assert_eq!(route.hops[4].pubkey, node7);
1208                         assert_eq!(route.hops[4].short_channel_id, 8);
1209                         assert_eq!(route.hops[4].fee_msat, 2000);
1210                         assert_eq!(route.hops[4].cltv_expiry_delta, 42);
1211                 }
1212         }
1213 }