_ 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 use bitcoin::blockdata::script::Builder;
   7 use bitcoin::blockdata::opcodes;
   8
   9 use chain::chaininterface::{ChainError, ChainWatchInterface};
  10 use ln::channelmanager;
  11 use ln::msgs::{ErrorAction,HandleError,RoutingMessageHandler,NetAddress,GlobalFeatures};
  12 use ln::msgs;
  13 use util::ser::Writeable;
  14 use util::logger::Logger;
  15
  16 use std::cmp;
  17 use std::sync::{RwLock,Arc};
  18 use std::collections::{HashMap,BinaryHeap};
  19 use std::collections::hash_map::Entry;
  20 use std;
  21
  22 /// A hop in a route
  23 #[derive(Clone)]
  24 pub struct RouteHop {
  25         pub pubkey: PublicKey,
  26         /// The channel that should be used from the previous hop to reach this node.
  27         pub short_channel_id: u64,
  28         /// The fee taken on this hop. For the last hop, this should be the full value of the payment.
  29         pub fee_msat: u64,
  30         /// The CLTV delta added for this hop. For the last hop, this should be the full CLTV value
  31         /// expected at the destination, in excess of the current block height.
  32         pub cltv_expiry_delta: u32,
  33 }
  34
  35 /// A route from us through the network to a destination
  36 #[derive(Clone)]
  37 pub struct Route {
  38         /// The list of hops, NOT INCLUDING our own, where the last hop is the destination. Thus, this
  39         /// must always be at least length one. By protocol rules, this may not currently exceed 20 in
  40         /// length.
  41         pub hops: Vec<RouteHop>,
  42 }
  43
  44 struct DirectionalChannelInfo {
  45         src_node_id: PublicKey,
  46         last_update: u32,
  47         enabled: bool,
  48         cltv_expiry_delta: u16,
  49         htlc_minimum_msat: u64,
  50         fee_base_msat: u32,
  51         fee_proportional_millionths: u32,
  52 }
  53
  54 impl std::fmt::Display for DirectionalChannelInfo {
  55         fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
  56                 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)?;
  57                 Ok(())
  58         }
  59 }
  60
  61 struct ChannelInfo {
  62         features: GlobalFeatures,
  63         one_to_two: DirectionalChannelInfo,
  64         two_to_one: DirectionalChannelInfo,
  65 }
  66
  67 impl std::fmt::Display for ChannelInfo {
  68         fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
  69                 write!(f, "features: {}, one_to_two: {}, two_to_one: {}", log_bytes!(self.features.encode()), self.one_to_two, self.two_to_one)?;
  70                 Ok(())
  71         }
  72 }
  73
  74 struct NodeInfo {
  75         #[cfg(feature = "non_bitcoin_chain_hash_routing")]
  76         channels: Vec<(u64, Sha256dHash)>,
  77         #[cfg(not(feature = "non_bitcoin_chain_hash_routing"))]
  78         channels: Vec<u64>,
  79
  80         lowest_inbound_channel_fee_base_msat: u32,
  81         lowest_inbound_channel_fee_proportional_millionths: u32,
  82
  83         features: GlobalFeatures,
  84         last_update: u32,
  85         rgb: [u8; 3],
  86         alias: [u8; 32],
  87         addresses: Vec<NetAddress>,
  88 }
  89
  90 impl std::fmt::Display for NodeInfo {
  91         fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
  92                 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[..])?;
  93                 Ok(())
  94         }
  95 }
  96
  97 struct NetworkMap {
  98         #[cfg(feature = "non_bitcoin_chain_hash_routing")]
  99         channels: HashMap<(u64, Sha256dHash), ChannelInfo>,
 100         #[cfg(not(feature = "non_bitcoin_chain_hash_routing"))]
 101         channels: HashMap<u64, ChannelInfo>,
 102
 103         our_node_id: PublicKey,
 104         nodes: HashMap<PublicKey, NodeInfo>,
 105 }
 106 struct MutNetworkMap<'a> {
 107         #[cfg(feature = "non_bitcoin_chain_hash_routing")]
 108         channels: &'a mut HashMap<(u64, Sha256dHash), ChannelInfo>,
 109         #[cfg(not(feature = "non_bitcoin_chain_hash_routing"))]
 110         channels: &'a mut HashMap<u64, ChannelInfo>,
 111         nodes: &'a mut HashMap<PublicKey, NodeInfo>,
 112 }
 113 impl NetworkMap {
 114         fn borrow_parts(&mut self) -> MutNetworkMap {
 115                 MutNetworkMap {
 116                         channels: &mut self.channels,
 117                         nodes: &mut self.nodes,
 118                 }
 119         }
 120 }
 121 impl std::fmt::Display for NetworkMap {
 122         fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
 123                 write!(f, "Node id {} network map\n[Channels]\n", log_pubkey!(self.our_node_id))?;
 124                 for (key, val) in self.channels.iter() {
 125                         write!(f, " {}: {}\n", key, val)?;
 126                 }
 127                 write!(f, "[Nodes]\n")?;
 128                 for (key, val) in self.nodes.iter() {
 129                         write!(f, " {}: {}\n", log_pubkey!(key), val)?;
 130                 }
 131                 Ok(())
 132         }
 133 }
 134
 135 impl NetworkMap {
 136         #[cfg(feature = "non_bitcoin_chain_hash_routing")]
 137         #[inline]
 138         fn get_key(short_channel_id: u64, chain_hash: Sha256dHash) -> (u64, Sha256dHash) {
 139                 (short_channel_id, chain_hash)
 140         }
 141
 142         #[cfg(not(feature = "non_bitcoin_chain_hash_routing"))]
 143         #[inline]
 144         fn get_key(short_channel_id: u64, _: Sha256dHash) -> u64 {
 145                 short_channel_id
 146         }
 147
 148         #[cfg(feature = "non_bitcoin_chain_hash_routing")]
 149         #[inline]
 150         fn get_short_id(id: &(u64, Sha256dHash)) -> &u64 {
 151                 &id.0
 152         }
 153
 154         #[cfg(not(feature = "non_bitcoin_chain_hash_routing"))]
 155         #[inline]
 156         fn get_short_id(id: &u64) -> &u64 {
 157                 id
 158         }
 159 }
 160
 161 /// A channel descriptor which provides a last-hop route to get_route
 162 pub struct RouteHint {
 163         pub src_node_id: PublicKey,
 164         pub short_channel_id: u64,
 165         pub fee_base_msat: u32,
 166         pub fee_proportional_millionths: u32,
 167         pub cltv_expiry_delta: u16,
 168         pub htlc_minimum_msat: u64,
 169 }
 170
 171 /// Tracks a view of the network, receiving updates from peers and generating Routes to
 172 /// payment destinations.
 173 pub struct Router {
 174         secp_ctx: Secp256k1<secp256k1::VerifyOnly>,
 175         network_map: RwLock<NetworkMap>,
 176         chain_monitor: Arc<ChainWatchInterface>,
 177         logger: Arc<Logger>,
 178 }
 179
 180 macro_rules! secp_verify_sig {
 181         ( $secp_ctx: expr, $msg: expr, $sig: expr, $pubkey: expr ) => {
 182                 match $secp_ctx.verify($msg, $sig, $pubkey) {
 183                         Ok(_) => {},
 184                         Err(_) => return Err(HandleError{err: "Invalid signature from remote node", action: None}),
 185                 }
 186         };
 187 }
 188
 189 impl RoutingMessageHandler for Router {
 190         fn handle_node_announcement(&self, msg: &msgs::NodeAnnouncement) -> Result<bool, HandleError> {
 191                 let msg_hash = Message::from_slice(&Sha256dHash::from_data(&msg.contents.encode()[..])[..]).unwrap();
 192                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.signature, &msg.contents.node_id);
 193
 194                 if msg.contents.features.requires_unknown_bits() {
 195                         panic!("Unknown-required-features NodeAnnouncements should never deserialize!");
 196                 }
 197
 198                 let mut network = self.network_map.write().unwrap();
 199                 match network.nodes.get_mut(&msg.contents.node_id) {
 200                         None => Err(HandleError{err: "No existing channels for node_announcement", action: Some(ErrorAction::IgnoreError)}),
 201                         Some(node) => {
 202                                 if node.last_update >= msg.contents.timestamp {
 203                                         return Err(HandleError{err: "Update older than last processed update", action: Some(ErrorAction::IgnoreError)});
 204                                 }
 205
 206                                 node.features = msg.contents.features.clone();
 207                                 node.last_update = msg.contents.timestamp;
 208                                 node.rgb = msg.contents.rgb;
 209                                 node.alias = msg.contents.alias;
 210                                 node.addresses = msg.contents.addresses.clone();
 211                                 Ok(msg.contents.excess_data.is_empty() && msg.contents.excess_address_data.is_empty() && !msg.contents.features.supports_unknown_bits())
 212                         }
 213                 }
 214         }
 215
 216         fn handle_channel_announcement(&self, msg: &msgs::ChannelAnnouncement) -> Result<bool, HandleError> {
 217                 if msg.contents.node_id_1 == msg.contents.node_id_2 || msg.contents.bitcoin_key_1 == msg.contents.bitcoin_key_2 {
 218                         return Err(HandleError{err: "Channel announcement node had a channel with itself", action: Some(ErrorAction::IgnoreError)});
 219                 }
 220
 221                 let msg_hash = Message::from_slice(&Sha256dHash::from_data(&msg.contents.encode()[..])[..]).unwrap();
 222                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.node_signature_1, &msg.contents.node_id_1);
 223                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.node_signature_2, &msg.contents.node_id_2);
 224                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.bitcoin_signature_1, &msg.contents.bitcoin_key_1);
 225                 secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.bitcoin_signature_2, &msg.contents.bitcoin_key_2);
 226
 227                 if msg.contents.features.requires_unknown_bits() {
 228                         panic!("Unknown-required-features ChannelAnnouncements should never deserialize!");
 229                 }
 230
 231                 let checked_utxo = match self.chain_monitor.get_chain_utxo(msg.contents.chain_hash, msg.contents.short_channel_id) {
 232                         Ok((script_pubkey, _value)) => {
 233                                 let expected_script = Builder::new().push_opcode(opcodes::All::OP_PUSHNUM_2)
 234                                                                     .push_slice(&msg.contents.bitcoin_key_1.serialize())
 235                                                                     .push_slice(&msg.contents.bitcoin_key_2.serialize())
 236                                                                     .push_opcode(opcodes::All::OP_PUSHNUM_2).push_opcode(opcodes::All::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
 237                                 if script_pubkey != expected_script {
 238                                         return Err(HandleError{err: "Channel announcement keys didn't match on-chain script", action: Some(ErrorAction::IgnoreError)});
 239                                 }
 240                                 //TODO: Check if value is worth storing, use it to inform routing, and compare it
 241                                 //to the new HTLC max field in channel_update
 242                                 true
 243                         },
 244                         Err(ChainError::NotSupported) => {
 245                                 // Tentatively accept, potentially exposing us to DoS attacks
 246                                 false
 247                         },
 248                         Err(ChainError::NotWatched) => {
 249                                 return Err(HandleError{err: "Channel announced on an unknown chain", action: Some(ErrorAction::IgnoreError)});
 250                         },
 251                         Err(ChainError::UnknownTx) => {
 252                                 return Err(HandleError{err: "Channel announced without corresponding UTXO entry", action: Some(ErrorAction::IgnoreError)});
 253                         },
 254                 };
 255
 256                 let mut network_lock = self.network_map.write().unwrap();
 257                 let network = network_lock.borrow_parts();
 258
 259                 let chan_info = ChannelInfo {
 260                                 features: msg.contents.features.clone(),
 261                                 one_to_two: DirectionalChannelInfo {
 262                                         src_node_id: msg.contents.node_id_1.clone(),
 263                                         last_update: 0,
 264                                         enabled: false,
 265                                         cltv_expiry_delta: u16::max_value(),
 266                                         htlc_minimum_msat: u64::max_value(),
 267                                         fee_base_msat: u32::max_value(),
 268                                         fee_proportional_millionths: u32::max_value(),
 269                                 },
 270                                 two_to_one: DirectionalChannelInfo {
 271                                         src_node_id: msg.contents.node_id_2.clone(),
 272                                         last_update: 0,
 273                                         enabled: false,
 274                                         cltv_expiry_delta: u16::max_value(),
 275                                         htlc_minimum_msat: u64::max_value(),
 276                                         fee_base_msat: u32::max_value(),
 277                                         fee_proportional_millionths: u32::max_value(),
 278                                 }
 279                         };
 280
 281                 match network.channels.entry(NetworkMap::get_key(msg.contents.short_channel_id, msg.contents.chain_hash)) {
 282                         Entry::Occupied(mut entry) => {
 283                                 //TODO: because asking the blockchain if short_channel_id is valid is only optional
 284                                 //in the blockchain API, we need to handle it smartly here, though its unclear
 285                                 //exactly how...
 286                                 if checked_utxo {
 287                                         // Either our UTXO provider is busted, there was a reorg, or the UTXO provider
 288                                         // only sometimes returns results. In any case remove the previous entry. Note
 289                                         // that the spec expects us to "blacklist" the node_ids involved, but we can't
 290                                         // do that because
 291                                         // a) we don't *require* a UTXO provider that always returns results.
 292                                         // b) we don't track UTXOs of channels we know about and remove them if they
 293                                         //    get reorg'd out.
 294                                         // c) it's unclear how to do so without exposing ourselves to massive DoS risk.
 295                                         Self::remove_channel_in_nodes(network.nodes, &entry.get(), msg.contents.short_channel_id);
 296                                         *entry.get_mut() = chan_info;
 297                                 } else {
 298                                         return Err(HandleError{err: "Already have knowledge of channel", action: Some(ErrorAction::IgnoreError)})
 299                                 }
 300                         },
 301                         Entry::Vacant(entry) => {
 302                                 entry.insert(chan_info);
 303                         }
 304                 };
 305
 306                 macro_rules! add_channel_to_node {
 307                         ( $node_id: expr ) => {
 308                                 match network.nodes.entry($node_id) {
 309                                         Entry::Occupied(node_entry) => {
 310                                                 node_entry.into_mut().channels.push(NetworkMap::get_key(msg.contents.short_channel_id, msg.contents.chain_hash));
 311                                         },
 312                                         Entry::Vacant(node_entry) => {
 313                                                 node_entry.insert(NodeInfo {
 314                                                         channels: vec!(NetworkMap::get_key(msg.contents.short_channel_id, msg.contents.chain_hash)),
 315                                                         lowest_inbound_channel_fee_base_msat: u32::max_value(),
 316                                                         lowest_inbound_channel_fee_proportional_millionths: u32::max_value(),
 317                                                         features: GlobalFeatures::new(),
 318                                                         last_update: 0,
 319                                                         rgb: [0; 3],
 320                                                         alias: [0; 32],
 321                                                         addresses: Vec::new(),
 322                                                 });
 323                                         }
 324                                 }
 325                         };
 326                 }
 327
 328                 add_channel_to_node!(msg.contents.node_id_1);
 329                 add_channel_to_node!(msg.contents.node_id_2);
 330
 331                 Ok(msg.contents.excess_data.is_empty() && !msg.contents.features.supports_unknown_bits())
 332         }
 333
 334         fn handle_htlc_fail_channel_update(&self, update: &msgs::HTLCFailChannelUpdate) {
 335                 match update {
 336                         &msgs::HTLCFailChannelUpdate::ChannelUpdateMessage { ref msg } => {
 337                                 let _ = self.handle_channel_update(msg);
 338                         },
 339                         &msgs::HTLCFailChannelUpdate::ChannelClosed { ref short_channel_id } => {
 340                                 let mut network = self.network_map.write().unwrap();
 341                                 if let Some(chan) = network.channels.remove(short_channel_id) {
 342                                         Self::remove_channel_in_nodes(&mut network.nodes, &chan, *short_channel_id);
 343                                 }
 344                         },
 345                 }
 346         }
 347
 348         fn handle_channel_update(&self, msg: &msgs::ChannelUpdate) -> Result<bool, HandleError> {
 349                 let mut network = self.network_map.write().unwrap();
 350                 let dest_node_id;
 351                 let chan_enabled = msg.contents.flags & (1 << 1) != (1 << 1);
 352                 let chan_was_enabled;
 353
 354                 match network.channels.get_mut(&NetworkMap::get_key(msg.contents.short_channel_id, msg.contents.chain_hash)) {
 355                         None => return Err(HandleError{err: "Couldn't find channel for update", action: Some(ErrorAction::IgnoreError)}),
 356                         Some(channel) => {
 357                                 macro_rules! maybe_update_channel_info {
 358                                         ( $target: expr) => {
 359                                                 if $target.last_update >= msg.contents.timestamp {
 360                                                         return Err(HandleError{err: "Update older than last processed update", action: Some(ErrorAction::IgnoreError)});
 361                                                 }
 362                                                 chan_was_enabled = $target.enabled;
 363                                                 $target.last_update = msg.contents.timestamp;
 364                                                 $target.enabled = chan_enabled;
 365                                                 $target.cltv_expiry_delta = msg.contents.cltv_expiry_delta;
 366                                                 $target.htlc_minimum_msat = msg.contents.htlc_minimum_msat;
 367                                                 $target.fee_base_msat = msg.contents.fee_base_msat;
 368                                                 $target.fee_proportional_millionths = msg.contents.fee_proportional_millionths;
 369                                         }
 370                                 }
 371
 372                                 let msg_hash = Message::from_slice(&Sha256dHash::from_data(&msg.contents.encode()[..])[..]).unwrap();
 373                                 if msg.contents.flags & 1 == 1 {
 374                                         dest_node_id = channel.one_to_two.src_node_id.clone();
 375                                         secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.signature, &channel.two_to_one.src_node_id);
 376                                         maybe_update_channel_info!(channel.two_to_one);
 377                                 } else {
 378                                         dest_node_id = channel.two_to_one.src_node_id.clone();
 379                                         secp_verify_sig!(self.secp_ctx, &msg_hash, &msg.signature, &channel.one_to_two.src_node_id);
 380                                         maybe_update_channel_info!(channel.one_to_two);
 381                                 }
 382                         }
 383                 }
 384
 385                 if chan_enabled {
 386                         let node = network.nodes.get_mut(&dest_node_id).unwrap();
 387                         node.lowest_inbound_channel_fee_base_msat = cmp::min(node.lowest_inbound_channel_fee_base_msat, msg.contents.fee_base_msat);
 388                         node.lowest_inbound_channel_fee_proportional_millionths = cmp::min(node.lowest_inbound_channel_fee_proportional_millionths, msg.contents.fee_proportional_millionths);
 389                 } else if chan_was_enabled {
 390                         let mut lowest_inbound_channel_fee_base_msat = u32::max_value();
 391                         let mut lowest_inbound_channel_fee_proportional_millionths = u32::max_value();
 392
 393                         {
 394                                 let node = network.nodes.get(&dest_node_id).unwrap();
 395
 396                                 for chan_id in node.channels.iter() {
 397                                         let chan = network.channels.get(chan_id).unwrap();
 398                                         if chan.one_to_two.src_node_id == dest_node_id {
 399                                                 lowest_inbound_channel_fee_base_msat = cmp::min(lowest_inbound_channel_fee_base_msat, chan.two_to_one.fee_base_msat);
 400                                                 lowest_inbound_channel_fee_proportional_millionths = cmp::min(lowest_inbound_channel_fee_proportional_millionths, chan.two_to_one.fee_proportional_millionths);
 401                                         } else {
 402                                                 lowest_inbound_channel_fee_base_msat = cmp::min(lowest_inbound_channel_fee_base_msat, chan.one_to_two.fee_base_msat);
 403                                                 lowest_inbound_channel_fee_proportional_millionths = cmp::min(lowest_inbound_channel_fee_proportional_millionths, chan.one_to_two.fee_proportional_millionths);
 404                                         }
 405                                 }
 406                         }
 407
 408                         //TODO: satisfy the borrow-checker without a double-map-lookup :(
 409                         let mut_node = network.nodes.get_mut(&dest_node_id).unwrap();
 410                         mut_node.lowest_inbound_channel_fee_base_msat = lowest_inbound_channel_fee_base_msat;
 411                         mut_node.lowest_inbound_channel_fee_proportional_millionths = lowest_inbound_channel_fee_proportional_millionths;
 412                 }
 413
 414                 Ok(msg.contents.excess_data.is_empty())
 415         }
 416 }
 417
 418 #[derive(Eq, PartialEq)]
 419 struct RouteGraphNode {
 420         pubkey: PublicKey,
 421         lowest_fee_to_peer_through_node: u64,
 422         lowest_fee_to_node: u64,
 423 }
 424
 425 impl cmp::Ord for RouteGraphNode {
 426         fn cmp(&self, other: &RouteGraphNode) -> cmp::Ordering {
 427                 other.lowest_fee_to_peer_through_node.cmp(&self.lowest_fee_to_peer_through_node)
 428                         .then_with(|| other.pubkey.serialize().cmp(&self.pubkey.serialize()))
 429         }
 430 }
 431
 432 impl cmp::PartialOrd for RouteGraphNode {
 433         fn partial_cmp(&self, other: &RouteGraphNode) -> Option<cmp::Ordering> {
 434                 Some(self.cmp(other))
 435         }
 436 }
 437
 438 struct DummyDirectionalChannelInfo {
 439         src_node_id: PublicKey,
 440         cltv_expiry_delta: u32,
 441         htlc_minimum_msat: u64,
 442         fee_base_msat: u32,
 443         fee_proportional_millionths: u32,
 444 }
 445
 446 impl Router {
 447         pub fn new(our_pubkey: PublicKey, chain_monitor: Arc<ChainWatchInterface>, logger: Arc<Logger>) -> Router {
 448                 let mut nodes = HashMap::new();
 449                 nodes.insert(our_pubkey.clone(), NodeInfo {
 450                         channels: Vec::new(),
 451                         lowest_inbound_channel_fee_base_msat: u32::max_value(),
 452                         lowest_inbound_channel_fee_proportional_millionths: u32::max_value(),
 453                         features: GlobalFeatures::new(),
 454                         last_update: 0,
 455                         rgb: [0; 3],
 456                         alias: [0; 32],
 457                         addresses: Vec::new(),
 458                 });
 459                 Router {
 460                         secp_ctx: Secp256k1::verification_only(),
 461                         network_map: RwLock::new(NetworkMap {
 462                                 channels: HashMap::new(),
 463                                 our_node_id: our_pubkey,
 464                                 nodes: nodes,
 465                         }),
 466                         chain_monitor,
 467                         logger,
 468                 }
 469         }
 470
 471         /// Dumps the entire network view of this Router to the logger provided in the constructor at
 472         /// level Trace
 473         pub fn trace_state(&self) {
 474                 log_trace!(self, "{}", self.network_map.read().unwrap());
 475         }
 476
 477         /// Get network addresses by node id
 478         pub fn get_addresses(&self, pubkey: &PublicKey) -> Option<Vec<NetAddress>> {
 479                 let network = self.network_map.read().unwrap();
 480                 network.nodes.get(pubkey).map(|n| n.addresses.clone())
 481         }
 482
 483         /// Marks a node as having failed a route. This will avoid re-using the node in routes for now,
 484         /// with an expotnential decay in node "badness". Note that there is deliberately no
 485         /// mark_channel_bad as a node may simply lie and suggest that an upstream channel from it is
 486         /// what failed the route and not the node itself. Instead, setting the blamed_upstream_node
 487         /// boolean will reduce the penalty, returning the node to usability faster. If the node is
 488         /// behaving correctly, it will disable the failing channel and we will use it again next time.
 489         pub fn mark_node_bad(&self, _node_id: &PublicKey, _blamed_upstream_node: bool) {
 490                 unimplemented!();
 491         }
 492
 493         fn remove_channel_in_nodes(nodes: &mut HashMap<PublicKey, NodeInfo>, chan: &ChannelInfo, short_channel_id: u64) {
 494                 macro_rules! remove_from_node {
 495                         ($node_id: expr) => {
 496                                 if let Entry::Occupied(mut entry) = nodes.entry($node_id) {
 497                                         entry.get_mut().channels.retain(|chan_id| {
 498                                                 short_channel_id != *NetworkMap::get_short_id(chan_id)
 499                                         });
 500                                         if entry.get().channels.is_empty() {
 501                                                 entry.remove_entry();
 502                                         }
 503                                 } else {
 504                                         panic!("Had channel that pointed to unknown node (ie inconsistent network map)!");
 505                                 }
 506                         }
 507                 }
 508                 remove_from_node!(chan.one_to_two.src_node_id);
 509                 remove_from_node!(chan.two_to_one.src_node_id);
 510         }
 511
 512         /// Gets a route from us to the given target node.
 513         /// Extra routing hops between known nodes and the target will be used if they are included in
 514         /// last_hops.
 515         /// If some channels aren't announced, it may be useful to fill in a first_hops with the
 516         /// results from a local ChannelManager::list_usable_channels() call. If it is filled in, our
 517         /// (this Router's) view of our local channels will be ignored, and only those in first_hops
 518         /// will be used. Panics if first_hops contains channels without short_channel_ids
 519         /// (ChannelManager::list_usable_channels will never include such channels).
 520         /// The fees on channels from us to next-hops are ignored (as they are assumed to all be
 521         /// equal), however the enabled/disabled bit on such channels as well as the htlc_minimum_msat
 522         /// *is* checked as they may change based on the receiving node.
 523         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> {
 524                 // TODO: Obviously *only* using total fee cost sucks. We should consider weighting by
 525                 // uptime/success in using a node in the past.
 526                 let network = self.network_map.read().unwrap();
 527
 528                 if *target == network.our_node_id {
 529                         return Err(HandleError{err: "Cannot generate a route to ourselves", action: None});
 530                 }
 531
 532                 if final_value_msat > 21_000_000 * 1_0000_0000 * 1000 {
 533                         return Err(HandleError{err: "Cannot generate a route of more value than all existing satoshis", action: None});
 534                 }
 535
 536                 // We do a dest-to-source Dijkstra's sorting by each node's distance from the destination
 537                 // plus the minimum per-HTLC fee to get from it to another node (aka "shitty A*").
 538                 // TODO: There are a few tweaks we could do, including possibly pre-calculating more stuff
 539                 // to use as the A* heuristic beyond just the cost to get one node further than the current
 540                 // one.
 541
 542                 let dummy_directional_info = DummyDirectionalChannelInfo { // used for first_hops routes
 543                         src_node_id: network.our_node_id.clone(),
 544                         cltv_expiry_delta: 0,
 545                         htlc_minimum_msat: 0,
 546                         fee_base_msat: 0,
 547                         fee_proportional_millionths: 0,
 548                 };
 549
 550                 let mut targets = BinaryHeap::new(); //TODO: Do we care about switching to eg Fibbonaci heap?
 551                 let mut dist = HashMap::with_capacity(network.nodes.len());
 552
 553                 let mut first_hop_targets = HashMap::with_capacity(if first_hops.is_some() { first_hops.as_ref().unwrap().len() } else { 0 });
 554                 if let Some(hops) = first_hops {
 555                         for chan in hops {
 556                                 let short_channel_id = chan.short_channel_id.expect("first_hops should be filled in with usable channels, not pending ones");
 557                                 if chan.remote_network_id == *target {
 558                                         return Ok(Route {
 559                                                 hops: vec![RouteHop {
 560                                                         pubkey: chan.remote_network_id,
 561                                                         short_channel_id,
 562                                                         fee_msat: final_value_msat,
 563                                                         cltv_expiry_delta: final_cltv,
 564                                                 }],
 565                                         });
 566                                 }
 567                                 first_hop_targets.insert(chan.remote_network_id, short_channel_id);
 568                         }
 569                         if first_hop_targets.is_empty() {
 570                                 return Err(HandleError{err: "Cannot route when there are no outbound routes away from us", action: None});
 571                         }
 572                 }
 573
 574                 macro_rules! add_entry {
 575                         // Adds entry which goes from the node pointed to by $directional_info to
 576                         // $dest_node_id over the channel with id $chan_id with fees described in
 577                         // $directional_info.
 578                         ( $chan_id: expr, $dest_node_id: expr, $directional_info: expr, $starting_fee_msat: expr ) => {
 579                                 //TODO: Explore simply adding fee to hit htlc_minimum_msat
 580                                 if $starting_fee_msat as u64 + final_value_msat > $directional_info.htlc_minimum_msat {
 581                                         let proportional_fee_millions = ($starting_fee_msat + final_value_msat).checked_mul($directional_info.fee_proportional_millionths as u64);
 582                                         if let Some(new_fee) = proportional_fee_millions.and_then(|part| {
 583                                                         ($directional_info.fee_base_msat as u64).checked_add(part / 1000000) })
 584                                         {
 585                                                 let mut total_fee = $starting_fee_msat as u64;
 586                                                 let hm_entry = dist.entry(&$directional_info.src_node_id);
 587                                                 let old_entry = hm_entry.or_insert_with(|| {
 588                                                         let node = network.nodes.get(&$directional_info.src_node_id).unwrap();
 589                                                         (u64::max_value(),
 590                                                                 node.lowest_inbound_channel_fee_base_msat,
 591                                                                 node.lowest_inbound_channel_fee_proportional_millionths,
 592                                                                 RouteHop {
 593                                                                         pubkey: $dest_node_id.clone(),
 594                                                                         short_channel_id: 0,
 595                                                                         fee_msat: 0,
 596                                                                         cltv_expiry_delta: 0,
 597                                                         })
 598                                                 });
 599                                                 if $directional_info.src_node_id != network.our_node_id {
 600                                                         // Ignore new_fee for channel-from-us as we assume all channels-from-us
 601                                                         // will have the same effective-fee
 602                                                         total_fee += new_fee;
 603                                                         if let Some(fee_inc) = final_value_msat.checked_add(total_fee).and_then(|inc| { (old_entry.2 as u64).checked_mul(inc) }) {
 604                                                                 total_fee += fee_inc / 1000000 + (old_entry.1 as u64);
 605                                                         } else {
 606                                                                 // max_value means we'll always fail the old_entry.0 > total_fee check
 607                                                                 total_fee = u64::max_value();
 608                                                         }
 609                                                 }
 610                                                 let new_graph_node = RouteGraphNode {
 611                                                         pubkey: $directional_info.src_node_id,
 612                                                         lowest_fee_to_peer_through_node: total_fee,
 613                                                         lowest_fee_to_node: $starting_fee_msat as u64 + new_fee,
 614                                                 };
 615                                                 if old_entry.0 > total_fee {
 616                                                         targets.push(new_graph_node);
 617                                                         old_entry.0 = total_fee;
 618                                                         old_entry.3 = RouteHop {
 619                                                                 pubkey: $dest_node_id.clone(),
 620                                                                 short_channel_id: $chan_id.clone(),
 621                                                                 fee_msat: new_fee, // This field is ignored on the last-hop anyway
 622                                                                 cltv_expiry_delta: $directional_info.cltv_expiry_delta as u32,
 623                                                         }
 624                                                 }
 625                                         }
 626                                 }
 627                         };
 628                 }
 629
 630                 macro_rules! add_entries_to_cheapest_to_target_node {
 631                         ( $node: expr, $node_id: expr, $fee_to_target_msat: expr ) => {
 632                                 if first_hops.is_some() {
 633                                         if let Some(first_hop) = first_hop_targets.get(&$node_id) {
 634                                                 add_entry!(first_hop, $node_id, dummy_directional_info, $fee_to_target_msat);
 635                                         }
 636                                 }
 637
 638                                 for chan_id in $node.channels.iter() {
 639                                         let chan = network.channels.get(chan_id).unwrap();
 640                                         if chan.one_to_two.src_node_id == *$node_id {
 641                                                 // ie $node is one, ie next hop in A* is two, via the two_to_one channel
 642                                                 if first_hops.is_none() || chan.two_to_one.src_node_id != network.our_node_id {
 643                                                         if chan.two_to_one.enabled {
 644                                                                 add_entry!(chan_id, chan.one_to_two.src_node_id, chan.two_to_one, $fee_to_target_msat);
 645                                                         }
 646                                                 }
 647                                         } else {
 648                                                 if first_hops.is_none() || chan.one_to_two.src_node_id != network.our_node_id {
 649                                                         if chan.one_to_two.enabled {
 650                                                                 add_entry!(chan_id, chan.two_to_one.src_node_id, chan.one_to_two, $fee_to_target_msat);
 651                                                         }
 652                                                 }
 653                                         }
 654                                 }
 655                         };
 656                 }
 657
 658                 match network.nodes.get(target) {
 659                         None => {},
 660                         Some(node) => {
 661                                 add_entries_to_cheapest_to_target_node!(node, target, 0);
 662                         },
 663                 }
 664
 665                 for hop in last_hops.iter() {
 666                         if first_hops.is_none() || hop.src_node_id != network.our_node_id { // first_hop overrules last_hops
 667                                 if network.nodes.get(&hop.src_node_id).is_some() {
 668                                         if first_hops.is_some() {
 669                                                 if let Some(first_hop) = first_hop_targets.get(&hop.src_node_id) {
 670                                                         add_entry!(first_hop, hop.src_node_id, dummy_directional_info, 0);
 671                                                 }
 672                                         }
 673                                         add_entry!(hop.short_channel_id, target, hop, 0);
 674                                 }
 675                         }
 676                 }
 677
 678                 while let Some(RouteGraphNode { pubkey, lowest_fee_to_node, .. }) = targets.pop() {
 679                         if pubkey == network.our_node_id {
 680                                 let mut res = vec!(dist.remove(&network.our_node_id).unwrap().3);
 681                                 while res.last().unwrap().pubkey != *target {
 682                                         let new_entry = match dist.remove(&res.last().unwrap().pubkey) {
 683                                                 Some(hop) => hop.3,
 684                                                 None => return Err(HandleError{err: "Failed to find a non-fee-overflowing path to the given destination", action: None}),
 685                                         };
 686                                         res.last_mut().unwrap().fee_msat = new_entry.fee_msat;
 687                                         res.last_mut().unwrap().cltv_expiry_delta = new_entry.cltv_expiry_delta;
 688                                         res.push(new_entry);
 689                                 }
 690                                 res.last_mut().unwrap().fee_msat = final_value_msat;
 691                                 res.last_mut().unwrap().cltv_expiry_delta = final_cltv;
 692                                 let route = Route { hops: res };
 693                                 log_trace!(self, "Got route: {}", log_route!(route));
 694                                 return Ok(route);
 695                         }
 696
 697                         match network.nodes.get(&pubkey) {
 698                                 None => {},
 699                                 Some(node) => {
 700                                         add_entries_to_cheapest_to_target_node!(node, &pubkey, lowest_fee_to_node);
 701                                 },
 702                         }
 703                 }
 704
 705                 Err(HandleError{err: "Failed to find a path to the given destination", action: None})
 706         }
 707 }
 708
 709 #[cfg(test)]
 710 mod tests {
 711         use chain::chaininterface;
 712         use ln::channelmanager;
 713         use ln::router::{Router,NodeInfo,NetworkMap,ChannelInfo,DirectionalChannelInfo,RouteHint};
 714         use ln::msgs::GlobalFeatures;
 715         use util::test_utils;
 716         use util::logger::Logger;
 717
 718         use bitcoin::util::hash::Sha256dHash;
 719         use bitcoin::network::constants::Network;
 720
 721         use hex;
 722
 723         use secp256k1::key::{PublicKey,SecretKey};
 724         use secp256k1::Secp256k1;
 725
 726         use std::sync::Arc;
 727
 728         #[test]
 729         fn route_test() {
 730                 let secp_ctx = Secp256k1::new();
 731                 let our_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap());
 732                 let logger: Arc<Logger> = Arc::new(test_utils::TestLogger::new());
 733                 let chain_monitor = Arc::new(chaininterface::ChainWatchInterfaceUtil::new(Network::Testnet, Arc::clone(&logger)));
 734                 let router = Router::new(our_id, chain_monitor, Arc::clone(&logger));
 735
 736                 // Build network from our_id to node8:
 737                 //
 738                 //        -1(1)2-  node1  -1(3)2-
 739                 //       /                       \
 740                 // our_id -1(12)2- node8 -1(13)2--- node3
 741                 //       \                       /
 742                 //        -1(2)2-  node2  -1(4)2-
 743                 //
 744                 //
 745                 // chan1  1-to-2: disabled
 746                 // chan1  2-to-1: enabled, 0 fee
 747                 //
 748                 // chan2  1-to-2: enabled, ignored fee
 749                 // chan2  2-to-1: enabled, 0 fee
 750                 //
 751                 // chan3  1-to-2: enabled, 0 fee
 752                 // chan3  2-to-1: enabled, 100 msat fee
 753                 //
 754                 // chan4  1-to-2: enabled, 100% fee
 755                 // chan4  2-to-1: enabled, 0 fee
 756                 //
 757                 // chan12 1-to-2: enabled, ignored fee
 758                 // chan12 2-to-1: enabled, 0 fee
 759                 //
 760                 // chan13 1-to-2: enabled, 200% fee
 761                 // chan13 2-to-1: enabled, 0 fee
 762                 //
 763                 //
 764                 //       -1(5)2- node4 -1(8)2--
 765                 //       |         2          |
 766                 //       |       (11)         |
 767                 //      /          1           \
 768                 // node3--1(6)2- node5 -1(9)2--- node7 (not in global route map)
 769                 //      \                      /
 770                 //       -1(7)2- node6 -1(10)2-
 771                 //
 772                 // chan5  1-to-2: enabled, 100 msat fee
 773                 // chan5  2-to-1: enabled, 0 fee
 774                 //
 775                 // chan6  1-to-2: enabled, 0 fee
 776                 // chan6  2-to-1: enabled, 0 fee
 777                 //
 778                 // chan7  1-to-2: enabled, 100% fee
 779                 // chan7  2-to-1: enabled, 0 fee
 780                 //
 781                 // chan8  1-to-2: enabled, variable fee (0 then 1000 msat)
 782                 // chan8  2-to-1: enabled, 0 fee
 783                 //
 784                 // chan9  1-to-2: enabled, 1001 msat fee
 785                 // chan9  2-to-1: enabled, 0 fee
 786                 //
 787                 // chan10 1-to-2: enabled, 0 fee
 788                 // chan10 2-to-1: enabled, 0 fee
 789                 //
 790                 // chan11 1-to-2: enabled, 0 fee
 791                 // chan11 2-to-1: enabled, 0 fee
 792
 793                 let node1 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &hex::decode("0202020202020202020202020202020202020202020202020202020202020202").unwrap()[..]).unwrap());
 794                 let node2 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &hex::decode("0303030303030303030303030303030303030303030303030303030303030303").unwrap()[..]).unwrap());
 795                 let node3 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &hex::decode("0404040404040404040404040404040404040404040404040404040404040404").unwrap()[..]).unwrap());
 796                 let node4 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &hex::decode("0505050505050505050505050505050505050505050505050505050505050505").unwrap()[..]).unwrap());
 797                 let node5 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &hex::decode("0606060606060606060606060606060606060606060606060606060606060606").unwrap()[..]).unwrap());
 798                 let node6 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &hex::decode("0707070707070707070707070707070707070707070707070707070707070707").unwrap()[..]).unwrap());
 799                 let node7 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &hex::decode("0808080808080808080808080808080808080808080808080808080808080808").unwrap()[..]).unwrap());
 800                 let node8 = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &hex::decode("0909090909090909090909090909090909090909090909090909090909090909").unwrap()[..]).unwrap());
 801
 802                 let zero_hash = Sha256dHash::from_data(&[0; 32]);
 803
 804                 {
 805                         let mut network = router.network_map.write().unwrap();
 806
 807                         network.nodes.insert(node1.clone(), NodeInfo {
 808                                 channels: vec!(NetworkMap::get_key(1, zero_hash.clone()), NetworkMap::get_key(3, zero_hash.clone())),
 809                                 lowest_inbound_channel_fee_base_msat: 100,
 810                                 lowest_inbound_channel_fee_proportional_millionths: 0,
 811                                 features: GlobalFeatures::new(),
 812                                 last_update: 1,
 813                                 rgb: [0; 3],
 814                                 alias: [0; 32],
 815                                 addresses: Vec::new(),
 816                         });
 817                         network.channels.insert(NetworkMap::get_key(1, zero_hash.clone()), ChannelInfo {
 818                                 features: GlobalFeatures::new(),
 819                                 one_to_two: DirectionalChannelInfo {
 820                                         src_node_id: our_id.clone(),
 821                                         last_update: 0,
 822                                         enabled: false,
 823                                         cltv_expiry_delta: u16::max_value(), // This value should be ignored
 824                                         htlc_minimum_msat: 0,
 825                                         fee_base_msat: u32::max_value(), // This value should be ignored
 826                                         fee_proportional_millionths: u32::max_value(), // This value should be ignored
 827                                 }, two_to_one: DirectionalChannelInfo {
 828                                         src_node_id: node1.clone(),
 829                                         last_update: 0,
 830                                         enabled: true,
 831                                         cltv_expiry_delta: 0,
 832                                         htlc_minimum_msat: 0,
 833                                         fee_base_msat: 0,
 834                                         fee_proportional_millionths: 0,
 835                                 },
 836                         });
 837                         network.nodes.insert(node2.clone(), NodeInfo {
 838                                 channels: vec!(NetworkMap::get_key(2, zero_hash.clone()), NetworkMap::get_key(4, zero_hash.clone())),
 839                                 lowest_inbound_channel_fee_base_msat: 0,
 840                                 lowest_inbound_channel_fee_proportional_millionths: 0,
 841                                 features: GlobalFeatures::new(),
 842                                 last_update: 1,
 843                                 rgb: [0; 3],
 844                                 alias: [0; 32],
 845                                 addresses: Vec::new(),
 846                         });
 847                         network.channels.insert(NetworkMap::get_key(2, zero_hash.clone()), ChannelInfo {
 848                                 features: GlobalFeatures::new(),
 849                                 one_to_two: DirectionalChannelInfo {
 850                                         src_node_id: our_id.clone(),
 851                                         last_update: 0,
 852                                         enabled: true,
 853                                         cltv_expiry_delta: u16::max_value(), // This value should be ignored
 854                                         htlc_minimum_msat: 0,
 855                                         fee_base_msat: u32::max_value(), // This value should be ignored
 856                                         fee_proportional_millionths: u32::max_value(), // This value should be ignored
 857                                 }, two_to_one: DirectionalChannelInfo {
 858                                         src_node_id: node2.clone(),
 859                                         last_update: 0,
 860                                         enabled: true,
 861                                         cltv_expiry_delta: 0,
 862                                         htlc_minimum_msat: 0,
 863                                         fee_base_msat: 0,
 864                                         fee_proportional_millionths: 0,
 865                                 },
 866                         });
 867                         network.nodes.insert(node8.clone(), NodeInfo {
 868                                 channels: vec!(NetworkMap::get_key(12, zero_hash.clone()), NetworkMap::get_key(13, zero_hash.clone())),
 869                                 lowest_inbound_channel_fee_base_msat: 0,
 870                                 lowest_inbound_channel_fee_proportional_millionths: 0,
 871                                 features: GlobalFeatures::new(),
 872                                 last_update: 1,
 873                                 rgb: [0; 3],
 874                                 alias: [0; 32],
 875                                 addresses: Vec::new(),
 876                         });
 877                         network.channels.insert(NetworkMap::get_key(12, zero_hash.clone()), ChannelInfo {
 878                                 features: GlobalFeatures::new(),
 879                                 one_to_two: DirectionalChannelInfo {
 880                                         src_node_id: our_id.clone(),
 881                                         last_update: 0,
 882                                         enabled: true,
 883                                         cltv_expiry_delta: u16::max_value(), // This value should be ignored
 884                                         htlc_minimum_msat: 0,
 885                                         fee_base_msat: u32::max_value(), // This value should be ignored
 886                                         fee_proportional_millionths: u32::max_value(), // This value should be ignored
 887                                 }, two_to_one: DirectionalChannelInfo {
 888                                         src_node_id: node8.clone(),
 889                                         last_update: 0,
 890                                         enabled: true,
 891                                         cltv_expiry_delta: 0,
 892                                         htlc_minimum_msat: 0,
 893                                         fee_base_msat: 0,
 894                                         fee_proportional_millionths: 0,
 895                                 },
 896                         });
 897                         network.nodes.insert(node3.clone(), NodeInfo {
 898                                 channels: vec!(
 899                                         NetworkMap::get_key(3, zero_hash.clone()),
 900                                         NetworkMap::get_key(4, zero_hash.clone()),
 901                                         NetworkMap::get_key(13, zero_hash.clone()),
 902                                         NetworkMap::get_key(5, zero_hash.clone()),
 903                                         NetworkMap::get_key(6, zero_hash.clone()),
 904                                         NetworkMap::get_key(7, zero_hash.clone())),
 905                                 lowest_inbound_channel_fee_base_msat: 0,
 906                                 lowest_inbound_channel_fee_proportional_millionths: 0,
 907                                 features: GlobalFeatures::new(),
 908                                 last_update: 1,
 909                                 rgb: [0; 3],
 910                                 alias: [0; 32],
 911                                 addresses: Vec::new(),
 912                         });
 913                         network.channels.insert(NetworkMap::get_key(3, zero_hash.clone()), ChannelInfo {
 914                                 features: GlobalFeatures::new(),
 915                                 one_to_two: DirectionalChannelInfo {
 916                                         src_node_id: node1.clone(),
 917                                         last_update: 0,
 918                                         enabled: true,
 919                                         cltv_expiry_delta: (3 << 8) | 1,
 920                                         htlc_minimum_msat: 0,
 921                                         fee_base_msat: 0,
 922                                         fee_proportional_millionths: 0,
 923                                 }, two_to_one: DirectionalChannelInfo {
 924                                         src_node_id: node3.clone(),
 925                                         last_update: 0,
 926                                         enabled: true,
 927                                         cltv_expiry_delta: (3 << 8) | 2,
 928                                         htlc_minimum_msat: 0,
 929                                         fee_base_msat: 100,
 930                                         fee_proportional_millionths: 0,
 931                                 },
 932                         });
 933                         network.channels.insert(NetworkMap::get_key(4, zero_hash.clone()), ChannelInfo {
 934                                 features: GlobalFeatures::new(),
 935                                 one_to_two: DirectionalChannelInfo {
 936                                         src_node_id: node2.clone(),
 937                                         last_update: 0,
 938                                         enabled: true,
 939                                         cltv_expiry_delta: (4 << 8) | 1,
 940                                         htlc_minimum_msat: 0,
 941                                         fee_base_msat: 0,
 942                                         fee_proportional_millionths: 1000000,
 943                                 }, two_to_one: DirectionalChannelInfo {
 944                                         src_node_id: node3.clone(),
 945                                         last_update: 0,
 946                                         enabled: true,
 947                                         cltv_expiry_delta: (4 << 8) | 2,
 948                                         htlc_minimum_msat: 0,
 949                                         fee_base_msat: 0,
 950                                         fee_proportional_millionths: 0,
 951                                 },
 952                         });
 953                         network.channels.insert(NetworkMap::get_key(13, zero_hash.clone()), ChannelInfo {
 954                                 features: GlobalFeatures::new(),
 955                                 one_to_two: DirectionalChannelInfo {
 956                                         src_node_id: node8.clone(),
 957                                         last_update: 0,
 958                                         enabled: true,
 959                                         cltv_expiry_delta: (13 << 8) | 1,
 960                                         htlc_minimum_msat: 0,
 961                                         fee_base_msat: 0,
 962                                         fee_proportional_millionths: 2000000,
 963                                 }, two_to_one: DirectionalChannelInfo {
 964                                         src_node_id: node3.clone(),
 965                                         last_update: 0,
 966                                         enabled: true,
 967                                         cltv_expiry_delta: (13 << 8) | 2,
 968                                         htlc_minimum_msat: 0,
 969                                         fee_base_msat: 0,
 970                                         fee_proportional_millionths: 0,
 971                                 },
 972                         });
 973                         network.nodes.insert(node4.clone(), NodeInfo {
 974                                 channels: vec!(NetworkMap::get_key(5, zero_hash.clone()), NetworkMap::get_key(11, zero_hash.clone())),
 975                                 lowest_inbound_channel_fee_base_msat: 0,
 976                                 lowest_inbound_channel_fee_proportional_millionths: 0,
 977                                 features: GlobalFeatures::new(),
 978                                 last_update: 1,
 979                                 rgb: [0; 3],
 980                                 alias: [0; 32],
 981                                 addresses: Vec::new(),
 982                         });
 983                         network.channels.insert(NetworkMap::get_key(5, zero_hash.clone()), ChannelInfo {
 984                                 features: GlobalFeatures::new(),
 985                                 one_to_two: DirectionalChannelInfo {
 986                                         src_node_id: node3.clone(),
 987                                         last_update: 0,
 988                                         enabled: true,
 989                                         cltv_expiry_delta: (5 << 8) | 1,
 990                                         htlc_minimum_msat: 0,
 991                                         fee_base_msat: 100,
 992                                         fee_proportional_millionths: 0,
 993                                 }, two_to_one: DirectionalChannelInfo {
 994                                         src_node_id: node4.clone(),
 995                                         last_update: 0,
 996                                         enabled: true,
 997                                         cltv_expiry_delta: (5 << 8) | 2,
 998                                         htlc_minimum_msat: 0,
 999                                         fee_base_msat: 0,
1000                                         fee_proportional_millionths: 0,
1001                                 },
1002                         });
1003                         network.nodes.insert(node5.clone(), NodeInfo {
1004                                 channels: vec!(NetworkMap::get_key(6, zero_hash.clone()), NetworkMap::get_key(11, zero_hash.clone())),
1005                                 lowest_inbound_channel_fee_base_msat: 0,
1006                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1007                                 features: GlobalFeatures::new(),
1008                                 last_update: 1,
1009                                 rgb: [0; 3],
1010                                 alias: [0; 32],
1011                                 addresses: Vec::new(),
1012                         });
1013                         network.channels.insert(NetworkMap::get_key(6, zero_hash.clone()), ChannelInfo {
1014                                 features: GlobalFeatures::new(),
1015                                 one_to_two: DirectionalChannelInfo {
1016                                         src_node_id: node3.clone(),
1017                                         last_update: 0,
1018                                         enabled: true,
1019                                         cltv_expiry_delta: (6 << 8) | 1,
1020                                         htlc_minimum_msat: 0,
1021                                         fee_base_msat: 0,
1022                                         fee_proportional_millionths: 0,
1023                                 }, two_to_one: DirectionalChannelInfo {
1024                                         src_node_id: node5.clone(),
1025                                         last_update: 0,
1026                                         enabled: true,
1027                                         cltv_expiry_delta: (6 << 8) | 2,
1028                                         htlc_minimum_msat: 0,
1029                                         fee_base_msat: 0,
1030                                         fee_proportional_millionths: 0,
1031                                 },
1032                         });
1033                         network.channels.insert(NetworkMap::get_key(11, zero_hash.clone()), ChannelInfo {
1034                                 features: GlobalFeatures::new(),
1035                                 one_to_two: DirectionalChannelInfo {
1036                                         src_node_id: node5.clone(),
1037                                         last_update: 0,
1038                                         enabled: true,
1039                                         cltv_expiry_delta: (11 << 8) | 1,
1040                                         htlc_minimum_msat: 0,
1041                                         fee_base_msat: 0,
1042                                         fee_proportional_millionths: 0,
1043                                 }, two_to_one: DirectionalChannelInfo {
1044                                         src_node_id: node4.clone(),
1045                                         last_update: 0,
1046                                         enabled: true,
1047                                         cltv_expiry_delta: (11 << 8) | 2,
1048                                         htlc_minimum_msat: 0,
1049                                         fee_base_msat: 0,
1050                                         fee_proportional_millionths: 0,
1051                                 },
1052                         });
1053                         network.nodes.insert(node6.clone(), NodeInfo {
1054                                 channels: vec!(NetworkMap::get_key(7, zero_hash.clone())),
1055                                 lowest_inbound_channel_fee_base_msat: 0,
1056                                 lowest_inbound_channel_fee_proportional_millionths: 0,
1057                                 features: GlobalFeatures::new(),
1058                                 last_update: 1,
1059                                 rgb: [0; 3],
1060                                 alias: [0; 32],
1061                                 addresses: Vec::new(),
1062                         });
1063                         network.channels.insert(NetworkMap::get_key(7, zero_hash.clone()), ChannelInfo {
1064                                 features: GlobalFeatures::new(),
1065                                 one_to_two: DirectionalChannelInfo {
1066                                         src_node_id: node3.clone(),
1067                                         last_update: 0,
1068                                         enabled: true,
1069                                         cltv_expiry_delta: (7 << 8) | 1,
1070                                         htlc_minimum_msat: 0,
1071                                         fee_base_msat: 0,
1072                                         fee_proportional_millionths: 1000000,
1073                                 }, two_to_one: DirectionalChannelInfo {
1074                                         src_node_id: node6.clone(),
1075                                         last_update: 0,
1076                                         enabled: true,
1077                                         cltv_expiry_delta: (7 << 8) | 2,
1078                                         htlc_minimum_msat: 0,
1079                                         fee_base_msat: 0,
1080                                         fee_proportional_millionths: 0,
1081                                 },
1082                         });
1083                 }
1084
1085                 { // Simple route to 3 via 2
1086                         let route = router.get_route(&node3, None, &Vec::new(), 100, 42).unwrap();
1087                         assert_eq!(route.hops.len(), 2);
1088
1089                         assert_eq!(route.hops[0].pubkey, node2);
1090                         assert_eq!(route.hops[0].short_channel_id, 2);
1091                         assert_eq!(route.hops[0].fee_msat, 100);
1092                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1093
1094                         assert_eq!(route.hops[1].pubkey, node3);
1095                         assert_eq!(route.hops[1].short_channel_id, 4);
1096                         assert_eq!(route.hops[1].fee_msat, 100);
1097                         assert_eq!(route.hops[1].cltv_expiry_delta, 42);
1098                 }
1099
1100                 { // Route to 1 via 2 and 3 because our channel to 1 is disabled
1101                         let route = router.get_route(&node1, None, &Vec::new(), 100, 42).unwrap();
1102                         assert_eq!(route.hops.len(), 3);
1103
1104                         assert_eq!(route.hops[0].pubkey, node2);
1105                         assert_eq!(route.hops[0].short_channel_id, 2);
1106                         assert_eq!(route.hops[0].fee_msat, 200);
1107                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1108
1109                         assert_eq!(route.hops[1].pubkey, node3);
1110                         assert_eq!(route.hops[1].short_channel_id, 4);
1111                         assert_eq!(route.hops[1].fee_msat, 100);
1112                         assert_eq!(route.hops[1].cltv_expiry_delta, (3 << 8) | 2);
1113
1114                         assert_eq!(route.hops[2].pubkey, node1);
1115                         assert_eq!(route.hops[2].short_channel_id, 3);
1116                         assert_eq!(route.hops[2].fee_msat, 100);
1117                         assert_eq!(route.hops[2].cltv_expiry_delta, 42);
1118                 }
1119
1120                 { // If we specify a channel to node8, that overrides our local channel view and that gets used
1121                         let our_chans = vec![channelmanager::ChannelDetails {
1122                                 channel_id: [0; 32],
1123                                 short_channel_id: Some(42),
1124                                 remote_network_id: node8.clone(),
1125                                 channel_value_satoshis: 0,
1126                                 user_id: 0,
1127                         }];
1128                         let route = router.get_route(&node3, Some(&our_chans), &Vec::new(), 100, 42).unwrap();
1129                         assert_eq!(route.hops.len(), 2);
1130
1131                         assert_eq!(route.hops[0].pubkey, node8);
1132                         assert_eq!(route.hops[0].short_channel_id, 42);
1133                         assert_eq!(route.hops[0].fee_msat, 200);
1134                         assert_eq!(route.hops[0].cltv_expiry_delta, (13 << 8) | 1);
1135
1136                         assert_eq!(route.hops[1].pubkey, node3);
1137                         assert_eq!(route.hops[1].short_channel_id, 13);
1138                         assert_eq!(route.hops[1].fee_msat, 100);
1139                         assert_eq!(route.hops[1].cltv_expiry_delta, 42);
1140                 }
1141
1142                 let mut last_hops = vec!(RouteHint {
1143                                 src_node_id: node4.clone(),
1144                                 short_channel_id: 8,
1145                                 fee_base_msat: 0,
1146                                 fee_proportional_millionths: 0,
1147                                 cltv_expiry_delta: (8 << 8) | 1,
1148                                 htlc_minimum_msat: 0,
1149                         }, RouteHint {
1150                                 src_node_id: node5.clone(),
1151                                 short_channel_id: 9,
1152                                 fee_base_msat: 1001,
1153                                 fee_proportional_millionths: 0,
1154                                 cltv_expiry_delta: (9 << 8) | 1,
1155                                 htlc_minimum_msat: 0,
1156                         }, RouteHint {
1157                                 src_node_id: node6.clone(),
1158                                 short_channel_id: 10,
1159                                 fee_base_msat: 0,
1160                                 fee_proportional_millionths: 0,
1161                                 cltv_expiry_delta: (10 << 8) | 1,
1162                                 htlc_minimum_msat: 0,
1163                         });
1164
1165                 { // Simple test across 2, 3, 5, and 4 via a last_hop channel
1166                         let route = router.get_route(&node7, None, &last_hops, 100, 42).unwrap();
1167                         assert_eq!(route.hops.len(), 5);
1168
1169                         assert_eq!(route.hops[0].pubkey, node2);
1170                         assert_eq!(route.hops[0].short_channel_id, 2);
1171                         assert_eq!(route.hops[0].fee_msat, 100);
1172                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1173
1174                         assert_eq!(route.hops[1].pubkey, node3);
1175                         assert_eq!(route.hops[1].short_channel_id, 4);
1176                         assert_eq!(route.hops[1].fee_msat, 0);
1177                         assert_eq!(route.hops[1].cltv_expiry_delta, (6 << 8) | 1);
1178
1179                         assert_eq!(route.hops[2].pubkey, node5);
1180                         assert_eq!(route.hops[2].short_channel_id, 6);
1181                         assert_eq!(route.hops[2].fee_msat, 0);
1182                         assert_eq!(route.hops[2].cltv_expiry_delta, (11 << 8) | 1);
1183
1184                         assert_eq!(route.hops[3].pubkey, node4);
1185                         assert_eq!(route.hops[3].short_channel_id, 11);
1186                         assert_eq!(route.hops[3].fee_msat, 0);
1187                         assert_eq!(route.hops[3].cltv_expiry_delta, (8 << 8) | 1);
1188
1189                         assert_eq!(route.hops[4].pubkey, node7);
1190                         assert_eq!(route.hops[4].short_channel_id, 8);
1191                         assert_eq!(route.hops[4].fee_msat, 100);
1192                         assert_eq!(route.hops[4].cltv_expiry_delta, 42);
1193                 }
1194
1195                 { // Simple test with outbound channel to 4 to test that last_hops and first_hops connect
1196                         let our_chans = vec![channelmanager::ChannelDetails {
1197                                 channel_id: [0; 32],
1198                                 short_channel_id: Some(42),
1199                                 remote_network_id: node4.clone(),
1200                                 channel_value_satoshis: 0,
1201                                 user_id: 0,
1202                         }];
1203                         let route = router.get_route(&node7, Some(&our_chans), &last_hops, 100, 42).unwrap();
1204                         assert_eq!(route.hops.len(), 2);
1205
1206                         assert_eq!(route.hops[0].pubkey, node4);
1207                         assert_eq!(route.hops[0].short_channel_id, 42);
1208                         assert_eq!(route.hops[0].fee_msat, 0);
1209                         assert_eq!(route.hops[0].cltv_expiry_delta, (8 << 8) | 1);
1210
1211                         assert_eq!(route.hops[1].pubkey, node7);
1212                         assert_eq!(route.hops[1].short_channel_id, 8);
1213                         assert_eq!(route.hops[1].fee_msat, 100);
1214                         assert_eq!(route.hops[1].cltv_expiry_delta, 42);
1215                 }
1216
1217                 last_hops[0].fee_base_msat = 1000;
1218
1219                 { // Revert to via 6 as the fee on 8 goes up
1220                         let route = router.get_route(&node7, None, &last_hops, 100, 42).unwrap();
1221                         assert_eq!(route.hops.len(), 4);
1222
1223                         assert_eq!(route.hops[0].pubkey, node2);
1224                         assert_eq!(route.hops[0].short_channel_id, 2);
1225                         assert_eq!(route.hops[0].fee_msat, 200); // fee increased as its % of value transferred across node
1226                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1227
1228                         assert_eq!(route.hops[1].pubkey, node3);
1229                         assert_eq!(route.hops[1].short_channel_id, 4);
1230                         assert_eq!(route.hops[1].fee_msat, 100);
1231                         assert_eq!(route.hops[1].cltv_expiry_delta, (7 << 8) | 1);
1232
1233                         assert_eq!(route.hops[2].pubkey, node6);
1234                         assert_eq!(route.hops[2].short_channel_id, 7);
1235                         assert_eq!(route.hops[2].fee_msat, 0);
1236                         assert_eq!(route.hops[2].cltv_expiry_delta, (10 << 8) | 1);
1237
1238                         assert_eq!(route.hops[3].pubkey, node7);
1239                         assert_eq!(route.hops[3].short_channel_id, 10);
1240                         assert_eq!(route.hops[3].fee_msat, 100);
1241                         assert_eq!(route.hops[3].cltv_expiry_delta, 42);
1242                 }
1243
1244                 { // ...but still use 8 for larger payments as 6 has a variable feerate
1245                         let route = router.get_route(&node7, None, &last_hops, 2000, 42).unwrap();
1246                         assert_eq!(route.hops.len(), 5);
1247
1248                         assert_eq!(route.hops[0].pubkey, node2);
1249                         assert_eq!(route.hops[0].short_channel_id, 2);
1250                         assert_eq!(route.hops[0].fee_msat, 3000);
1251                         assert_eq!(route.hops[0].cltv_expiry_delta, (4 << 8) | 1);
1252
1253                         assert_eq!(route.hops[1].pubkey, node3);
1254                         assert_eq!(route.hops[1].short_channel_id, 4);
1255                         assert_eq!(route.hops[1].fee_msat, 0);
1256                         assert_eq!(route.hops[1].cltv_expiry_delta, (6 << 8) | 1);
1257
1258                         assert_eq!(route.hops[2].pubkey, node5);
1259                         assert_eq!(route.hops[2].short_channel_id, 6);
1260                         assert_eq!(route.hops[2].fee_msat, 0);
1261                         assert_eq!(route.hops[2].cltv_expiry_delta, (11 << 8) | 1);
1262
1263                         assert_eq!(route.hops[3].pubkey, node4);
1264                         assert_eq!(route.hops[3].short_channel_id, 11);
1265                         assert_eq!(route.hops[3].fee_msat, 1000);
1266                         assert_eq!(route.hops[3].cltv_expiry_delta, (8 << 8) | 1);
1267
1268                         assert_eq!(route.hops[4].pubkey, node7);
1269                         assert_eq!(route.hops[4].short_channel_id, 8);
1270                         assert_eq!(route.hops[4].fee_msat, 2000);
1271                         assert_eq!(route.hops[4].cltv_expiry_delta, 42);
1272                 }
1273         }
1274 }