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

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