Relicense as dual Apache-2.0 + MIT
[rust-lightning] / lightning / src / routing / router.rs
1 // This file is Copyright its original authors, visible in version control
2 // history.
3 //
4 // This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
5 // or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
6 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
7 // You may not use this file except in accordance with one or both of these
8 // licenses.
9
10 //! The top-level routing/network map tracking logic lives here.
11 //!
12 //! You probably want to create a NetGraphMsgHandler and use that as your RoutingMessageHandler and then
13 //! interrogate it to get routes for your own payments.
14
15 use bitcoin::secp256k1::key::PublicKey;
16
17 use ln::channelmanager;
18 use ln::features::{ChannelFeatures, NodeFeatures};
19 use ln::msgs::{DecodeError, ErrorAction, LightningError, MAX_VALUE_MSAT};
20 use routing::network_graph::{NetworkGraph, RoutingFees};
21 use util::ser::{Writeable, Readable};
22 use util::logger::Logger;
23
24 use std::cmp;
25 use std::collections::{HashMap,BinaryHeap};
26 use std::ops::Deref;
27
28 /// A hop in a route
29 #[derive(Clone, PartialEq)]
30 pub struct RouteHop {
31         /// The node_id of the node at this hop.
32         pub pubkey: PublicKey,
33         /// The node_announcement features of the node at this hop. For the last hop, these may be
34         /// amended to match the features present in the invoice this node generated.
35         pub node_features: NodeFeatures,
36         /// The channel that should be used from the previous hop to reach this node.
37         pub short_channel_id: u64,
38         /// The channel_announcement features of the channel that should be used from the previous hop
39         /// to reach this node.
40         pub channel_features: ChannelFeatures,
41         /// The fee taken on this hop. For the last hop, this should be the full value of the payment.
42         pub fee_msat: u64,
43         /// The CLTV delta added for this hop. For the last hop, this should be the full CLTV value
44         /// expected at the destination, in excess of the current block height.
45         pub cltv_expiry_delta: u32,
46 }
47
48 impl Writeable for Vec<RouteHop> {
49         fn write<W: ::util::ser::Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
50                 (self.len() as u8).write(writer)?;
51                 for hop in self.iter() {
52                         hop.pubkey.write(writer)?;
53                         hop.node_features.write(writer)?;
54                         hop.short_channel_id.write(writer)?;
55                         hop.channel_features.write(writer)?;
56                         hop.fee_msat.write(writer)?;
57                         hop.cltv_expiry_delta.write(writer)?;
58                 }
59                 Ok(())
60         }
61 }
62
63 impl Readable for Vec<RouteHop> {
64         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Vec<RouteHop>, DecodeError> {
65                 let hops_count: u8 = Readable::read(reader)?;
66                 let mut hops = Vec::with_capacity(hops_count as usize);
67                 for _ in 0..hops_count {
68                         hops.push(RouteHop {
69                                 pubkey: Readable::read(reader)?,
70                                 node_features: Readable::read(reader)?,
71                                 short_channel_id: Readable::read(reader)?,
72                                 channel_features: Readable::read(reader)?,
73                                 fee_msat: Readable::read(reader)?,
74                                 cltv_expiry_delta: Readable::read(reader)?,
75                         });
76                 }
77                 Ok(hops)
78         }
79 }
80
81 /// A route directs a payment from the sender (us) to the recipient. If the recipient supports MPP,
82 /// it can take multiple paths. Each path is composed of one or more hops through the network.
83 #[derive(Clone, PartialEq)]
84 pub struct Route {
85         /// The list of routes taken for a single (potentially-)multi-part payment. The pubkey of the
86         /// last RouteHop in each path must be the same.
87         /// Each entry represents a list of hops, NOT INCLUDING our own, where the last hop is the
88         /// destination. Thus, this must always be at least length one. While the maximum length of any
89         /// given path is variable, keeping the length of any path to less than 20 should currently
90         /// ensure it is viable.
91         pub paths: Vec<Vec<RouteHop>>,
92 }
93
94 impl Writeable for Route {
95         fn write<W: ::util::ser::Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
96                 (self.paths.len() as u64).write(writer)?;
97                 for hops in self.paths.iter() {
98                         hops.write(writer)?;
99                 }
100                 Ok(())
101         }
102 }
103
104 impl Readable for Route {
105         fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Route, DecodeError> {
106                 let path_count: u64 = Readable::read(reader)?;
107                 let mut paths = Vec::with_capacity(cmp::min(path_count, 128) as usize);
108                 for _ in 0..path_count {
109                         paths.push(Readable::read(reader)?);
110                 }
111                 Ok(Route { paths })
112         }
113 }
114
115 /// A channel descriptor which provides a last-hop route to get_route
116 pub struct RouteHint {
117         /// The node_id of the non-target end of the route
118         pub src_node_id: PublicKey,
119         /// The short_channel_id of this channel
120         pub short_channel_id: u64,
121         /// The fees which must be paid to use this channel
122         pub fees: RoutingFees,
123         /// The difference in CLTV values between this node and the next node.
124         pub cltv_expiry_delta: u16,
125         /// The minimum value, in msat, which must be relayed to the next hop.
126         pub htlc_minimum_msat: u64,
127 }
128
129 #[derive(Eq, PartialEq)]
130 struct RouteGraphNode {
131         pubkey: PublicKey,
132         lowest_fee_to_peer_through_node: u64,
133         lowest_fee_to_node: u64,
134 }
135
136 impl cmp::Ord for RouteGraphNode {
137         fn cmp(&self, other: &RouteGraphNode) -> cmp::Ordering {
138                 other.lowest_fee_to_peer_through_node.cmp(&self.lowest_fee_to_peer_through_node)
139                         .then_with(|| other.pubkey.serialize().cmp(&self.pubkey.serialize()))
140         }
141 }
142
143 impl cmp::PartialOrd for RouteGraphNode {
144         fn partial_cmp(&self, other: &RouteGraphNode) -> Option<cmp::Ordering> {
145                 Some(self.cmp(other))
146         }
147 }
148
149 struct DummyDirectionalChannelInfo {
150         cltv_expiry_delta: u32,
151         htlc_minimum_msat: u64,
152         fees: RoutingFees,
153 }
154
155
156 /// Gets a route from us to the given target node.
157 ///
158 /// Extra routing hops between known nodes and the target will be used if they are included in
159 /// last_hops.
160 ///
161 /// If some channels aren't announced, it may be useful to fill in a first_hops with the
162 /// results from a local ChannelManager::list_usable_channels() call. If it is filled in, our
163 /// view of our local channels (from net_graph_msg_handler) will be ignored, and only those in first_hops
164 /// will be used.
165 ///
166 /// Panics if first_hops contains channels without short_channel_ids
167 /// (ChannelManager::list_usable_channels will never include such channels).
168 ///
169 /// The fees on channels from us to next-hops are ignored (as they are assumed to all be
170 /// equal), however the enabled/disabled bit on such channels as well as the htlc_minimum_msat
171 /// *is* checked as they may change based on the receiving node.
172 pub fn get_route<L: Deref>(our_node_id: &PublicKey, network: &NetworkGraph, target: &PublicKey, first_hops: Option<&[channelmanager::ChannelDetails]>,
173         last_hops: &[RouteHint], final_value_msat: u64, final_cltv: u32, logger: L) -> Result<Route, LightningError> where L::Target: Logger {
174         // TODO: Obviously *only* using total fee cost sucks. We should consider weighting by
175         // uptime/success in using a node in the past.
176         if *target == *our_node_id {
177                 return Err(LightningError{err: "Cannot generate a route to ourselves".to_owned(), action: ErrorAction::IgnoreError});
178         }
179
180         if final_value_msat > MAX_VALUE_MSAT {
181                 return Err(LightningError{err: "Cannot generate a route of more value than all existing satoshis".to_owned(), action: ErrorAction::IgnoreError});
182         }
183
184         // We do a dest-to-source Dijkstra's sorting by each node's distance from the destination
185         // plus the minimum per-HTLC fee to get from it to another node (aka "shitty A*").
186         // TODO: There are a few tweaks we could do, including possibly pre-calculating more stuff
187         // to use as the A* heuristic beyond just the cost to get one node further than the current
188         // one.
189
190         let dummy_directional_info = DummyDirectionalChannelInfo { // used for first_hops routes
191                 cltv_expiry_delta: 0,
192                 htlc_minimum_msat: 0,
193                 fees: RoutingFees {
194                         base_msat: 0,
195                         proportional_millionths: 0,
196                 }
197         };
198
199         let mut targets = BinaryHeap::new(); //TODO: Do we care about switching to eg Fibbonaci heap?
200         let mut dist = HashMap::with_capacity(network.get_nodes().len());
201
202         let mut first_hop_targets = HashMap::with_capacity(if first_hops.is_some() { first_hops.as_ref().unwrap().len() } else { 0 });
203         if let Some(hops) = first_hops {
204                 for chan in hops {
205                         let short_channel_id = chan.short_channel_id.expect("first_hops should be filled in with usable channels, not pending ones");
206                         if chan.remote_network_id == *target {
207                                 return Ok(Route {
208                                         paths: vec![vec![RouteHop {
209                                                 pubkey: chan.remote_network_id,
210                                                 node_features: chan.counterparty_features.to_context(),
211                                                 short_channel_id,
212                                                 channel_features: chan.counterparty_features.to_context(),
213                                                 fee_msat: final_value_msat,
214                                                 cltv_expiry_delta: final_cltv,
215                                         }]],
216                                 });
217                         }
218                         first_hop_targets.insert(chan.remote_network_id, (short_channel_id, chan.counterparty_features.clone()));
219                 }
220                 if first_hop_targets.is_empty() {
221                         return Err(LightningError{err: "Cannot route when there are no outbound routes away from us".to_owned(), action: ErrorAction::IgnoreError});
222                 }
223         }
224
225         macro_rules! add_entry {
226                 // Adds entry which goes from $src_node_id to $dest_node_id
227                 // over the channel with id $chan_id with fees described in
228                 // $directional_info.
229                 ( $chan_id: expr, $src_node_id: expr, $dest_node_id: expr, $directional_info: expr, $chan_features: expr, $starting_fee_msat: expr ) => {
230                         //TODO: Explore simply adding fee to hit htlc_minimum_msat
231                         if $starting_fee_msat as u64 + final_value_msat >= $directional_info.htlc_minimum_msat {
232                                 let proportional_fee_millions = ($starting_fee_msat + final_value_msat).checked_mul($directional_info.fees.proportional_millionths as u64);
233                                 if let Some(new_fee) = proportional_fee_millions.and_then(|part| {
234                                                 ($directional_info.fees.base_msat as u64).checked_add(part / 1000000) })
235                                 {
236                                         let mut total_fee = $starting_fee_msat as u64;
237                                         let hm_entry = dist.entry(&$src_node_id);
238                                         let old_entry = hm_entry.or_insert_with(|| {
239                                                 let node = network.get_nodes().get(&$src_node_id).unwrap();
240                                                 let mut fee_base_msat = u32::max_value();
241                                                 let mut fee_proportional_millionths = u32::max_value();
242                                                 if let Some(fees) = node.lowest_inbound_channel_fees {
243                                                         fee_base_msat = fees.base_msat;
244                                                         fee_proportional_millionths = fees.proportional_millionths;
245                                                 };
246                                                 (u64::max_value(),
247                                                         fee_base_msat,
248                                                         fee_proportional_millionths,
249                                                         RouteHop {
250                                                                 pubkey: $dest_node_id.clone(),
251                                                                 node_features: NodeFeatures::empty(),
252                                                                 short_channel_id: 0,
253                                                                 channel_features: $chan_features.clone(),
254                                                                 fee_msat: 0,
255                                                                 cltv_expiry_delta: 0,
256                                                         },
257                                                 )
258                                         });
259                                         if $src_node_id != *our_node_id {
260                                                 // Ignore new_fee for channel-from-us as we assume all channels-from-us
261                                                 // will have the same effective-fee
262                                                 total_fee += new_fee;
263                                                 if let Some(fee_inc) = final_value_msat.checked_add(total_fee).and_then(|inc| { (old_entry.2 as u64).checked_mul(inc) }) {
264                                                         total_fee += fee_inc / 1000000 + (old_entry.1 as u64);
265                                                 } else {
266                                                         // max_value means we'll always fail the old_entry.0 > total_fee check
267                                                         total_fee = u64::max_value();
268                                                 }
269                                         }
270                                         let new_graph_node = RouteGraphNode {
271                                                 pubkey: $src_node_id,
272                                                 lowest_fee_to_peer_through_node: total_fee,
273                                                 lowest_fee_to_node: $starting_fee_msat as u64 + new_fee,
274                                         };
275                                         if old_entry.0 > total_fee {
276                                                 targets.push(new_graph_node);
277                                                 old_entry.0 = total_fee;
278                                                 old_entry.3 = RouteHop {
279                                                         pubkey: $dest_node_id.clone(),
280                                                         node_features: NodeFeatures::empty(),
281                                                         short_channel_id: $chan_id.clone(),
282                                                         channel_features: $chan_features.clone(),
283                                                         fee_msat: new_fee, // This field is ignored on the last-hop anyway
284                                                         cltv_expiry_delta: $directional_info.cltv_expiry_delta as u32,
285                                                 }
286                                         }
287                                 }
288                         }
289                 };
290         }
291
292         macro_rules! add_entries_to_cheapest_to_target_node {
293                 ( $node: expr, $node_id: expr, $fee_to_target_msat: expr ) => {
294                         if first_hops.is_some() {
295                                 if let Some(&(ref first_hop, ref features)) = first_hop_targets.get(&$node_id) {
296                                         add_entry!(first_hop, *our_node_id, $node_id, dummy_directional_info, features.to_context(), $fee_to_target_msat);
297                                 }
298                         }
299
300                         let features;
301                         if let Some(node_info) = $node.announcement_info.as_ref() {
302                                 features = node_info.features.clone();
303                         } else {
304                                 features = NodeFeatures::empty();
305                         }
306
307                         if !features.requires_unknown_bits() {
308                                 for chan_id in $node.channels.iter() {
309                                         let chan = network.get_channels().get(chan_id).unwrap();
310                                         if !chan.features.requires_unknown_bits() {
311                                                 if chan.node_one == *$node_id {
312                                                         // ie $node is one, ie next hop in A* is two, via the two_to_one channel
313                                                         if first_hops.is_none() || chan.node_two != *our_node_id {
314                                                                 if let Some(two_to_one) = chan.two_to_one.as_ref() {
315                                                                         if two_to_one.enabled {
316                                                                                 add_entry!(chan_id, chan.node_two, chan.node_one, two_to_one, chan.features, $fee_to_target_msat);
317                                                                         }
318                                                                 }
319                                                         }
320                                                 } else {
321                                                         if first_hops.is_none() || chan.node_one != *our_node_id {
322                                                                 if let Some(one_to_two) = chan.one_to_two.as_ref() {
323                                                                         if one_to_two.enabled {
324                                                                                 add_entry!(chan_id, chan.node_one, chan.node_two, one_to_two, chan.features, $fee_to_target_msat);
325                                                                         }
326                                                                 }
327
328                                                         }
329                                                 }
330                                         }
331                                 }
332                         }
333                 };
334         }
335
336         match network.get_nodes().get(target) {
337                 None => {},
338                 Some(node) => {
339                         add_entries_to_cheapest_to_target_node!(node, target, 0);
340                 },
341         }
342
343         for hop in last_hops.iter() {
344                 if first_hops.is_none() || hop.src_node_id != *our_node_id { // first_hop overrules last_hops
345                         if network.get_nodes().get(&hop.src_node_id).is_some() {
346                                 if first_hops.is_some() {
347                                         if let Some(&(ref first_hop, ref features)) = first_hop_targets.get(&hop.src_node_id) {
348                                                 // Currently there are no channel-context features defined, so we are a
349                                                 // bit lazy here. In the future, we should pull them out via our
350                                                 // ChannelManager, but there's no reason to waste the space until we
351                                                 // need them.
352                                                 add_entry!(first_hop, *our_node_id , hop.src_node_id, dummy_directional_info, features.to_context(), 0);
353                                         }
354                                 }
355                                 // BOLT 11 doesn't allow inclusion of features for the last hop hints, which
356                                 // really sucks, cause we're gonna need that eventually.
357                                 add_entry!(hop.short_channel_id, hop.src_node_id, target, hop, ChannelFeatures::empty(), 0);
358                         }
359                 }
360         }
361
362         while let Some(RouteGraphNode { pubkey, lowest_fee_to_node, .. }) = targets.pop() {
363                 if pubkey == *our_node_id {
364                         let mut res = vec!(dist.remove(&our_node_id).unwrap().3);
365                         loop {
366                                 if let Some(&(_, ref features)) = first_hop_targets.get(&res.last().unwrap().pubkey) {
367                                         res.last_mut().unwrap().node_features = features.to_context();
368                                 } else if let Some(node) = network.get_nodes().get(&res.last().unwrap().pubkey) {
369                                         if let Some(node_info) = node.announcement_info.as_ref() {
370                                                 res.last_mut().unwrap().node_features = node_info.features.clone();
371                                         } else {
372                                                 res.last_mut().unwrap().node_features = NodeFeatures::empty();
373                                         }
374                                 } else {
375                                         // We should be able to fill in features for everything except the last
376                                         // hop, if the last hop was provided via a BOLT 11 invoice (though we
377                                         // should be able to extend it further as BOLT 11 does have feature
378                                         // flags for the last hop node itself).
379                                         assert!(res.last().unwrap().pubkey == *target);
380                                 }
381                                 if res.last().unwrap().pubkey == *target {
382                                         break;
383                                 }
384
385                                 let new_entry = match dist.remove(&res.last().unwrap().pubkey) {
386                                         Some(hop) => hop.3,
387                                         None => return Err(LightningError{err: "Failed to find a non-fee-overflowing path to the given destination".to_owned(), action: ErrorAction::IgnoreError}),
388                                 };
389                                 res.last_mut().unwrap().fee_msat = new_entry.fee_msat;
390                                 res.last_mut().unwrap().cltv_expiry_delta = new_entry.cltv_expiry_delta;
391                                 res.push(new_entry);
392                         }
393                         res.last_mut().unwrap().fee_msat = final_value_msat;
394                         res.last_mut().unwrap().cltv_expiry_delta = final_cltv;
395                         let route = Route { paths: vec![res] };
396                         log_trace!(logger, "Got route: {}", log_route!(route));
397                         return Ok(route);
398                 }
399
400                 match network.get_nodes().get(&pubkey) {
401                         None => {},
402                         Some(node) => {
403                                 add_entries_to_cheapest_to_target_node!(node, &pubkey, lowest_fee_to_node);
404                         },
405                 }
406         }
407
408         Err(LightningError{err: "Failed to find a path to the given destination".to_owned(), action: ErrorAction::IgnoreError})
409 }
410
411 #[cfg(test)]
412 mod tests {
413         use chain::chaininterface;
414         use routing::router::{get_route, RouteHint, RoutingFees};
415         use routing::network_graph::NetGraphMsgHandler;
416         use ln::features::{ChannelFeatures, InitFeatures, NodeFeatures};
417         use ln::msgs::{ErrorAction, LightningError, OptionalField, UnsignedChannelAnnouncement, ChannelAnnouncement, RoutingMessageHandler,
418            NodeAnnouncement, UnsignedNodeAnnouncement, ChannelUpdate, UnsignedChannelUpdate};
419         use ln::channelmanager;
420         use util::test_utils;
421         use util::ser::Writeable;
422
423         use bitcoin::hashes::sha256d::Hash as Sha256dHash;
424         use bitcoin::hashes::Hash;
425         use bitcoin::network::constants::Network;
426         use bitcoin::blockdata::constants::genesis_block;
427         use bitcoin::util::hash::BitcoinHash;
428
429         use hex;
430
431         use bitcoin::secp256k1::key::{PublicKey,SecretKey};
432         use bitcoin::secp256k1::{Secp256k1, All};
433
434         use std::sync::Arc;
435
436         // Using the same keys for LN and BTC ids
437         fn add_channel(net_graph_msg_handler: &NetGraphMsgHandler<Arc<chaininterface::ChainWatchInterfaceUtil>, Arc<test_utils::TestLogger>>, secp_ctx: &Secp256k1<All>, node_1_privkey: &SecretKey,
438            node_2_privkey: &SecretKey, features: ChannelFeatures, short_channel_id: u64) {
439                 let node_id_1 = PublicKey::from_secret_key(&secp_ctx, node_1_privkey);
440                 let node_id_2 = PublicKey::from_secret_key(&secp_ctx, node_2_privkey);
441
442                 let unsigned_announcement = UnsignedChannelAnnouncement {
443                         features,
444                         chain_hash: genesis_block(Network::Testnet).header.bitcoin_hash(),
445                         short_channel_id,
446                         node_id_1,
447                         node_id_2,
448                         bitcoin_key_1: node_id_1,
449                         bitcoin_key_2: node_id_2,
450                         excess_data: Vec::new(),
451                 };
452
453                 let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
454                 let valid_announcement = ChannelAnnouncement {
455                         node_signature_1: secp_ctx.sign(&msghash, node_1_privkey),
456                         node_signature_2: secp_ctx.sign(&msghash, node_2_privkey),
457                         bitcoin_signature_1: secp_ctx.sign(&msghash, node_1_privkey),
458                         bitcoin_signature_2: secp_ctx.sign(&msghash, node_2_privkey),
459                         contents: unsigned_announcement.clone(),
460                 };
461                 match net_graph_msg_handler.handle_channel_announcement(&valid_announcement) {
462                         Ok(res) => assert!(res),
463                         _ => panic!()
464                 };
465         }
466
467         fn update_channel(net_graph_msg_handler: &NetGraphMsgHandler<Arc<chaininterface::ChainWatchInterfaceUtil>, Arc<test_utils::TestLogger>>, secp_ctx: &Secp256k1<All>, node_privkey: &SecretKey, update: UnsignedChannelUpdate) {
468                 let msghash = hash_to_message!(&Sha256dHash::hash(&update.encode()[..])[..]);
469                 let valid_channel_update = ChannelUpdate {
470                         signature: secp_ctx.sign(&msghash, node_privkey),
471                         contents: update.clone()
472                 };
473
474                 match net_graph_msg_handler.handle_channel_update(&valid_channel_update) {
475                         Ok(res) => assert!(res),
476                         // Err(_) => panic!()
477                         Err(e) => println!("{:?}", e.err)
478                 };
479         }
480
481
482         fn add_or_update_node(net_graph_msg_handler: &NetGraphMsgHandler<Arc<chaininterface::ChainWatchInterfaceUtil>, Arc<test_utils::TestLogger>>, secp_ctx: &Secp256k1<All>, node_privkey: &SecretKey,
483            features: NodeFeatures, timestamp: u32) {
484                 let node_id = PublicKey::from_secret_key(&secp_ctx, node_privkey);
485                 let unsigned_announcement = UnsignedNodeAnnouncement {
486                         features,
487                         timestamp,
488                         node_id,
489                         rgb: [0; 3],
490                         alias: [0; 32],
491                         addresses: Vec::new(),
492                         excess_address_data: Vec::new(),
493                         excess_data: Vec::new(),
494                 };
495                 let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
496                 let valid_announcement = NodeAnnouncement {
497                         signature: secp_ctx.sign(&msghash, node_privkey),
498                         contents: unsigned_announcement.clone()
499                 };
500
501                 match net_graph_msg_handler.handle_node_announcement(&valid_announcement) {
502                         Ok(_) => (),
503                         Err(_) => panic!()
504                 };
505         }
506
507         #[test]
508         fn route_test() {
509                 let secp_ctx = Secp256k1::new();
510                 let our_privkey = &SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
511                 let our_id = PublicKey::from_secret_key(&secp_ctx, our_privkey);
512                 let logger = Arc::new(test_utils::TestLogger::new());
513                 let chain_monitor = Arc::new(chaininterface::ChainWatchInterfaceUtil::new(Network::Testnet));
514                 let net_graph_msg_handler = NetGraphMsgHandler::new(chain_monitor, Arc::clone(&logger));
515                 // Build network from our_id to node8:
516                 //
517                 //        -1(1)2-  node1  -1(3)2-
518                 //       /                       \
519                 // our_id -1(12)2- node8 -1(13)2--- node3
520                 //       \                       /
521                 //        -1(2)2-  node2  -1(4)2-
522                 //
523                 //
524                 // chan1  1-to-2: disabled
525                 // chan1  2-to-1: enabled, 0 fee
526                 //
527                 // chan2  1-to-2: enabled, ignored fee
528                 // chan2  2-to-1: enabled, 0 fee
529                 //
530                 // chan3  1-to-2: enabled, 0 fee
531                 // chan3  2-to-1: enabled, 100 msat fee
532                 //
533                 // chan4  1-to-2: enabled, 100% fee
534                 // chan4  2-to-1: enabled, 0 fee
535                 //
536                 // chan12 1-to-2: enabled, ignored fee
537                 // chan12 2-to-1: enabled, 0 fee
538                 //
539                 // chan13 1-to-2: enabled, 200% fee
540                 // chan13 2-to-1: enabled, 0 fee
541                 //
542                 //
543                 //       -1(5)2- node4 -1(8)2--
544                 //       |         2          |
545                 //       |       (11)         |
546                 //      /          1           \
547                 // node3--1(6)2- node5 -1(9)2--- node7 (not in global route map)
548                 //      \                      /
549                 //       -1(7)2- node6 -1(10)2-
550                 //
551                 // chan5  1-to-2: enabled, 100 msat fee
552                 // chan5  2-to-1: enabled, 0 fee
553                 //
554                 // chan6  1-to-2: enabled, 0 fee
555                 // chan6  2-to-1: enabled, 0 fee
556                 //
557                 // chan7  1-to-2: enabled, 100% fee
558                 // chan7  2-to-1: enabled, 0 fee
559                 //
560                 // chan8  1-to-2: enabled, variable fee (0 then 1000 msat)
561                 // chan8  2-to-1: enabled, 0 fee
562                 //
563                 // chan9  1-to-2: enabled, 1001 msat fee
564                 // chan9  2-to-1: enabled, 0 fee
565                 //
566                 // chan10 1-to-2: enabled, 0 fee
567                 // chan10 2-to-1: enabled, 0 fee
568                 //
569                 // chan11 1-to-2: enabled, 0 fee
570                 // chan11 2-to-1: enabled, 0 fee
571
572                 let node1_privkey = &SecretKey::from_slice(&hex::decode("0202020202020202020202020202020202020202020202020202020202020202").unwrap()[..]).unwrap();
573                 let node2_privkey = &SecretKey::from_slice(&hex::decode("0303030303030303030303030303030303030303030303030303030303030303").unwrap()[..]).unwrap();
574                 let node3_privkey = &SecretKey::from_slice(&hex::decode("0404040404040404040404040404040404040404040404040404040404040404").unwrap()[..]).unwrap();
575                 let node4_privkey = &SecretKey::from_slice(&hex::decode("0505050505050505050505050505050505050505050505050505050505050505").unwrap()[..]).unwrap();
576                 let node5_privkey = &SecretKey::from_slice(&hex::decode("0606060606060606060606060606060606060606060606060606060606060606").unwrap()[..]).unwrap();
577                 let node6_privkey = &SecretKey::from_slice(&hex::decode("0707070707070707070707070707070707070707070707070707070707070707").unwrap()[..]).unwrap();
578                 let node7_privkey = &SecretKey::from_slice(&hex::decode("0808080808080808080808080808080808080808080808080808080808080808").unwrap()[..]).unwrap();
579                 let node8_privkey = &SecretKey::from_slice(&hex::decode("0909090909090909090909090909090909090909090909090909090909090909").unwrap()[..]).unwrap();
580
581
582                 let node1 = PublicKey::from_secret_key(&secp_ctx, node1_privkey);
583                 let node2 = PublicKey::from_secret_key(&secp_ctx, node2_privkey);
584                 let node3 = PublicKey::from_secret_key(&secp_ctx, node3_privkey);
585                 let node4 = PublicKey::from_secret_key(&secp_ctx, node4_privkey);
586                 let node5 = PublicKey::from_secret_key(&secp_ctx, node5_privkey);
587                 let node6 = PublicKey::from_secret_key(&secp_ctx, node6_privkey);
588                 let node7 = PublicKey::from_secret_key(&secp_ctx, node7_privkey);
589                 let node8 = PublicKey::from_secret_key(&secp_ctx, node8_privkey);
590
591                 macro_rules! id_to_feature_flags {
592                         // Set the feature flags to the id'th odd (ie non-required) feature bit so that we can
593                         // test for it later.
594                         ($id: expr) => { {
595                                 let idx = ($id - 1) * 2 + 1;
596                                 if idx > 8*3 {
597                                         vec![1 << (idx - 8*3), 0, 0, 0]
598                                 } else if idx > 8*2 {
599                                         vec![1 << (idx - 8*2), 0, 0]
600                                 } else if idx > 8*1 {
601                                         vec![1 << (idx - 8*1), 0]
602                                 } else {
603                                         vec![1 << idx]
604                                 }
605                         } }
606                 }
607
608                 add_channel(&net_graph_msg_handler, &secp_ctx, our_privkey, node1_privkey, ChannelFeatures::from_le_bytes(id_to_feature_flags!(1)), 1);
609                 update_channel(&net_graph_msg_handler, &secp_ctx, node1_privkey, UnsignedChannelUpdate {
610                         chain_hash: genesis_block(Network::Testnet).header.bitcoin_hash(),
611                         short_channel_id: 1,
612                         timestamp: 1,
613                         flags: 1,
614                         cltv_expiry_delta: 0,
615                         htlc_minimum_msat: 0,
616                         htlc_maximum_msat: OptionalField::Absent,
617                         fee_base_msat: 0,
618                         fee_proportional_millionths: 0,
619                         excess_data: Vec::new()
620                 });
621                 add_or_update_node(&net_graph_msg_handler, &secp_ctx, node1_privkey, NodeFeatures::from_le_bytes(id_to_feature_flags!(1)), 0);
622
623                 add_channel(&net_graph_msg_handler, &secp_ctx, our_privkey, node2_privkey, ChannelFeatures::from_le_bytes(id_to_feature_flags!(2)), 2);
624                 update_channel(&net_graph_msg_handler, &secp_ctx, our_privkey, UnsignedChannelUpdate {
625                         chain_hash: genesis_block(Network::Testnet).header.bitcoin_hash(),
626                         short_channel_id: 2,
627                         timestamp: 1,
628                         flags: 0,
629                         cltv_expiry_delta: u16::max_value(),
630                         htlc_minimum_msat: 0,
631                         htlc_maximum_msat: OptionalField::Absent,
632                         fee_base_msat: u32::max_value(),
633                         fee_proportional_millionths: u32::max_value(),
634                         excess_data: Vec::new()
635                 });
636                 update_channel(&net_graph_msg_handler, &secp_ctx, node2_privkey, UnsignedChannelUpdate {
637                         chain_hash: genesis_block(Network::Testnet).header.bitcoin_hash(),
638                         short_channel_id: 2,
639                         timestamp: 1,
640                         flags: 1,
641                         cltv_expiry_delta: 0,
642                         htlc_minimum_msat: 0,
643                         htlc_maximum_msat: OptionalField::Absent,
644                         fee_base_msat: 0,
645                         fee_proportional_millionths: 0,
646                         excess_data: Vec::new()
647                 });
648
649                 add_or_update_node(&net_graph_msg_handler, &secp_ctx, node2_privkey, NodeFeatures::from_le_bytes(id_to_feature_flags!(2)), 0);
650
651                 add_channel(&net_graph_msg_handler, &secp_ctx, our_privkey, node8_privkey, ChannelFeatures::from_le_bytes(id_to_feature_flags!(12)), 12);
652                 update_channel(&net_graph_msg_handler, &secp_ctx, our_privkey, UnsignedChannelUpdate {
653                         chain_hash: genesis_block(Network::Testnet).header.bitcoin_hash(),
654                         short_channel_id: 12,
655                         timestamp: 1,
656                         flags: 0,
657                         cltv_expiry_delta: u16::max_value(),
658                         htlc_minimum_msat: 0,
659                         htlc_maximum_msat: OptionalField::Absent,
660                         fee_base_msat: u32::max_value(),
661                         fee_proportional_millionths: u32::max_value(),
662                         excess_data: Vec::new()
663                 });
664                 update_channel(&net_graph_msg_handler, &secp_ctx, node8_privkey, UnsignedChannelUpdate {
665                         chain_hash: genesis_block(Network::Testnet).header.bitcoin_hash(),
666                         short_channel_id: 12,
667                         timestamp: 1,
668                         flags: 1,
669                         cltv_expiry_delta: 0,
670                         htlc_minimum_msat: 0,
671                         htlc_maximum_msat: OptionalField::Absent,
672                         fee_base_msat: 0,
673                         fee_proportional_millionths: 0,
674                         excess_data: Vec::new()
675                 });
676
677
678                 add_or_update_node(&net_graph_msg_handler, &secp_ctx, node8_privkey, NodeFeatures::from_le_bytes(id_to_feature_flags!(8)), 0);
679
680                 add_channel(&net_graph_msg_handler, &secp_ctx, node1_privkey, node3_privkey, ChannelFeatures::from_le_bytes(id_to_feature_flags!(3)), 3);
681                 update_channel(&net_graph_msg_handler, &secp_ctx, node1_privkey, UnsignedChannelUpdate {
682                         chain_hash: genesis_block(Network::Testnet).header.bitcoin_hash(),
683                         short_channel_id: 3,
684                         timestamp: 1,
685                         flags: 0,
686                         cltv_expiry_delta: (3 << 8) | 1,
687                         htlc_minimum_msat: 0,
688                         htlc_maximum_msat: OptionalField::Absent,
689                         fee_base_msat: 0,
690                         fee_proportional_millionths: 0,
691                         excess_data: Vec::new()
692                 });
693                 update_channel(&net_graph_msg_handler, &secp_ctx, node3_privkey, UnsignedChannelUpdate {
694                         chain_hash: genesis_block(Network::Testnet).header.bitcoin_hash(),
695                         short_channel_id: 3,
696                         timestamp: 1,
697                         flags: 1,
698                         cltv_expiry_delta: (3 << 8) | 2,
699                         htlc_minimum_msat: 0,
700                         htlc_maximum_msat: OptionalField::Absent,
701                         fee_base_msat: 100,
702                         fee_proportional_millionths: 0,
703                         excess_data: Vec::new()
704                 });
705
706
707                 add_channel(&net_graph_msg_handler, &secp_ctx, node2_privkey, node3_privkey, ChannelFeatures::from_le_bytes(id_to_feature_flags!(4)), 4);
708                 update_channel(&net_graph_msg_handler, &secp_ctx, node2_privkey, UnsignedChannelUpdate {
709                         chain_hash: genesis_block(Network::Testnet).header.bitcoin_hash(),
710                         short_channel_id: 4,
711                         timestamp: 1,
712                         flags: 0,
713                         cltv_expiry_delta: (4 << 8) | 1,
714                         htlc_minimum_msat: 0,
715                         htlc_maximum_msat: OptionalField::Absent,
716                         fee_base_msat: 0,
717                         fee_proportional_millionths: 1000000,
718                         excess_data: Vec::new()
719                 });
720                 update_channel(&net_graph_msg_handler, &secp_ctx, node3_privkey, UnsignedChannelUpdate {
721                         chain_hash: genesis_block(Network::Testnet).header.bitcoin_hash(),
722                         short_channel_id: 4,
723                         timestamp: 1,
724                         flags: 1,
725                         cltv_expiry_delta: (4 << 8) | 2,
726                         htlc_minimum_msat: 0,
727                         htlc_maximum_msat: OptionalField::Absent,
728                         fee_base_msat: 0,
729                         fee_proportional_millionths: 0,
730                         excess_data: Vec::new()
731                 });
732
733                 add_channel(&net_graph_msg_handler, &secp_ctx, node8_privkey, node3_privkey, ChannelFeatures::from_le_bytes(id_to_feature_flags!(13)), 13);
734                 update_channel(&net_graph_msg_handler, &secp_ctx, node8_privkey, UnsignedChannelUpdate {
735                         chain_hash: genesis_block(Network::Testnet).header.bitcoin_hash(),
736                         short_channel_id: 13,
737                         timestamp: 1,
738                         flags: 0,
739                         cltv_expiry_delta: (13 << 8) | 1,
740                         htlc_minimum_msat: 0,
741                         htlc_maximum_msat: OptionalField::Absent,
742                         fee_base_msat: 0,
743                         fee_proportional_millionths: 2000000,
744                         excess_data: Vec::new()
745                 });
746                 update_channel(&net_graph_msg_handler, &secp_ctx, node3_privkey, UnsignedChannelUpdate {
747                         chain_hash: genesis_block(Network::Testnet).header.bitcoin_hash(),
748                         short_channel_id: 13,
749                         timestamp: 1,
750                         flags: 1,
751                         cltv_expiry_delta: (13 << 8) | 2,
752                         htlc_minimum_msat: 0,
753                         htlc_maximum_msat: OptionalField::Absent,
754                         fee_base_msat: 0,
755                         fee_proportional_millionths: 0,
756                         excess_data: Vec::new()
757                 });
758                 add_or_update_node(&net_graph_msg_handler, &secp_ctx, node3_privkey, NodeFeatures::from_le_bytes(id_to_feature_flags!(3)), 0);
759                 add_channel(&net_graph_msg_handler, &secp_ctx, node3_privkey, node5_privkey, ChannelFeatures::from_le_bytes(id_to_feature_flags!(6)), 6);
760
761                 update_channel(&net_graph_msg_handler, &secp_ctx, node3_privkey, UnsignedChannelUpdate {
762                         chain_hash: genesis_block(Network::Testnet).header.bitcoin_hash(),
763                         short_channel_id: 6,
764                         timestamp: 1,
765                         flags: 0,
766                         cltv_expiry_delta: (6 << 8) | 1,
767                         htlc_minimum_msat: 0,
768                         htlc_maximum_msat: OptionalField::Absent,
769                         fee_base_msat: 0,
770                         fee_proportional_millionths: 0,
771                         excess_data: Vec::new()
772                 });
773                 update_channel(&net_graph_msg_handler, &secp_ctx, node5_privkey, UnsignedChannelUpdate {
774                         chain_hash: genesis_block(Network::Testnet).header.bitcoin_hash(),
775                         short_channel_id: 6,
776                         timestamp: 1,
777                         flags: 1,
778                         cltv_expiry_delta: (6 << 8) | 2,
779                         htlc_minimum_msat: 0,
780                         htlc_maximum_msat: OptionalField::Absent,
781                         fee_base_msat: 0,
782                         fee_proportional_millionths: 0,
783                         excess_data: Vec::new()
784                 });
785
786                 add_channel(&net_graph_msg_handler, &secp_ctx, node5_privkey, node4_privkey, ChannelFeatures::from_le_bytes(id_to_feature_flags!(11)), 11);
787                 update_channel(&net_graph_msg_handler, &secp_ctx, node5_privkey, UnsignedChannelUpdate {
788                         chain_hash: genesis_block(Network::Testnet).header.bitcoin_hash(),
789                         short_channel_id: 11,
790                         timestamp: 1,
791                         flags: 0,
792                         cltv_expiry_delta: (11 << 8) | 1,
793                         htlc_minimum_msat: 0,
794                         htlc_maximum_msat: OptionalField::Absent,
795                         fee_base_msat: 0,
796                         fee_proportional_millionths: 0,
797                         excess_data: Vec::new()
798                 });
799                 update_channel(&net_graph_msg_handler, &secp_ctx, node4_privkey, UnsignedChannelUpdate {
800                         chain_hash: genesis_block(Network::Testnet).header.bitcoin_hash(),
801                         short_channel_id: 11,
802                         timestamp: 1,
803                         flags: 1,
804                         cltv_expiry_delta: (11 << 8) | 2,
805                         htlc_minimum_msat: 0,
806                         htlc_maximum_msat: OptionalField::Absent,
807                         fee_base_msat: 0,
808                         fee_proportional_millionths: 0,
809                         excess_data: Vec::new()
810                 });
811                 add_or_update_node(&net_graph_msg_handler, &secp_ctx, node5_privkey, NodeFeatures::from_le_bytes(id_to_feature_flags!(5)), 0);
812                 add_or_update_node(&net_graph_msg_handler, &secp_ctx, node4_privkey, NodeFeatures::from_le_bytes(id_to_feature_flags!(4)), 0);
813
814                 add_channel(&net_graph_msg_handler, &secp_ctx, node3_privkey, node6_privkey, ChannelFeatures::from_le_bytes(id_to_feature_flags!(7)), 7);
815
816                 update_channel(&net_graph_msg_handler, &secp_ctx, node3_privkey, UnsignedChannelUpdate {
817                         chain_hash: genesis_block(Network::Testnet).header.bitcoin_hash(),
818                         short_channel_id: 7,
819                         timestamp: 1,
820                         flags: 0,
821                         cltv_expiry_delta: (7 << 8) | 1,
822                         htlc_minimum_msat: 0,
823                         htlc_maximum_msat: OptionalField::Absent,
824                         fee_base_msat: 0,
825                         fee_proportional_millionths: 1000000,
826                         excess_data: Vec::new()
827                 });
828                 update_channel(&net_graph_msg_handler, &secp_ctx, node6_privkey, UnsignedChannelUpdate {
829                         chain_hash: genesis_block(Network::Testnet).header.bitcoin_hash(),
830                         short_channel_id: 7,
831                         timestamp: 1,
832                         flags: 1,
833                         cltv_expiry_delta: (7 << 8) | 2,
834                         htlc_minimum_msat: 0,
835                         htlc_maximum_msat: OptionalField::Absent,
836                         fee_base_msat: 0,
837                         fee_proportional_millionths: 0,
838                         excess_data: Vec::new()
839                 });
840
841                 add_or_update_node(&net_graph_msg_handler, &secp_ctx, node6_privkey, NodeFeatures::from_le_bytes(id_to_feature_flags!(6)), 0);
842
843                 // Simple route to 3 via 2
844                 let route = get_route(&our_id, &net_graph_msg_handler.network_graph.read().unwrap(), &node3, None, &Vec::new(), 100, 42, Arc::clone(&logger)).unwrap();
845                 assert_eq!(route.paths[0].len(), 2);
846
847                 assert_eq!(route.paths[0][0].pubkey, node2);
848                 assert_eq!(route.paths[0][0].short_channel_id, 2);
849                 assert_eq!(route.paths[0][0].fee_msat, 100);
850                 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 8) | 1);
851                 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags!(2));
852                 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags!(2));
853
854                 assert_eq!(route.paths[0][1].pubkey, node3);
855                 assert_eq!(route.paths[0][1].short_channel_id, 4);
856                 assert_eq!(route.paths[0][1].fee_msat, 100);
857                 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
858                 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags!(3));
859                 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags!(4));
860
861
862                 // // Disable channels 4 and 12 by flags=2
863                 update_channel(&net_graph_msg_handler, &secp_ctx, node2_privkey, UnsignedChannelUpdate {
864                         chain_hash: genesis_block(Network::Testnet).header.bitcoin_hash(),
865                         short_channel_id: 4,
866                         timestamp: 2,
867                         flags: 2, // to disable
868                         cltv_expiry_delta: 0,
869                         htlc_minimum_msat: 0,
870                         htlc_maximum_msat: OptionalField::Absent,
871                         fee_base_msat: 0,
872                         fee_proportional_millionths: 0,
873                         excess_data: Vec::new()
874                 });
875                 update_channel(&net_graph_msg_handler, &secp_ctx, our_privkey, UnsignedChannelUpdate {
876                         chain_hash: genesis_block(Network::Testnet).header.bitcoin_hash(),
877                         short_channel_id: 12,
878                         timestamp: 2,
879                         flags: 2, // to disable
880                         cltv_expiry_delta: 0,
881                         htlc_minimum_msat: 0,
882                         htlc_maximum_msat: OptionalField::Absent,
883                         fee_base_msat: 0,
884                         fee_proportional_millionths: 0,
885                         excess_data: Vec::new()
886                 });
887
888                 // If all the channels require some features we don't understand, route should fail
889                 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id, &net_graph_msg_handler.network_graph.read().unwrap(), &node3, None, &Vec::new(), 100, 42, Arc::clone(&logger)) {
890                         assert_eq!(err, "Failed to find a path to the given destination");
891                 } else { panic!(); }
892
893                 // If we specify a channel to node8, that overrides our local channel view and that gets used
894                 let our_chans = vec![channelmanager::ChannelDetails {
895                         channel_id: [0; 32],
896                         short_channel_id: Some(42),
897                         remote_network_id: node8.clone(),
898                         counterparty_features: InitFeatures::from_le_bytes(vec![0b11]),
899                         channel_value_satoshis: 0,
900                         user_id: 0,
901                         outbound_capacity_msat: 0,
902                         inbound_capacity_msat: 0,
903                         is_live: true,
904                 }];
905                 let route = get_route(&our_id, &net_graph_msg_handler.network_graph.read().unwrap(), &node3, Some(&our_chans),  &Vec::new(), 100, 42, Arc::clone(&logger)).unwrap();
906                 assert_eq!(route.paths[0].len(), 2);
907
908                 assert_eq!(route.paths[0][0].pubkey, node8);
909                 assert_eq!(route.paths[0][0].short_channel_id, 42);
910                 assert_eq!(route.paths[0][0].fee_msat, 200);
911                 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 8) | 1);
912                 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
913                 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
914
915                 assert_eq!(route.paths[0][1].pubkey, node3);
916                 assert_eq!(route.paths[0][1].short_channel_id, 13);
917                 assert_eq!(route.paths[0][1].fee_msat, 100);
918                 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
919                 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags!(3));
920                 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags!(13));
921
922                 // Re-enable channels 4 and 12
923                 update_channel(&net_graph_msg_handler, &secp_ctx, node2_privkey, UnsignedChannelUpdate {
924                         chain_hash: genesis_block(Network::Testnet).header.bitcoin_hash(),
925                         short_channel_id: 4,
926                         timestamp: 3,
927                         flags: 0, // to enable
928                         cltv_expiry_delta: (4 << 8) | 1,
929                         htlc_minimum_msat: 0,
930                         htlc_maximum_msat: OptionalField::Absent,
931                         fee_base_msat: 0,
932                         fee_proportional_millionths: 1000000,
933                         excess_data: Vec::new()
934                 });
935                 update_channel(&net_graph_msg_handler, &secp_ctx, our_privkey, UnsignedChannelUpdate {
936                         chain_hash: genesis_block(Network::Testnet).header.bitcoin_hash(),
937                         short_channel_id: 12,
938                         timestamp: 3,
939                         flags: 0, // to enable
940                         cltv_expiry_delta: u16::max_value(),
941                         htlc_minimum_msat: 0,
942                         htlc_maximum_msat: OptionalField::Absent,
943                         fee_base_msat: u32::max_value(),
944                         fee_proportional_millionths: u32::max_value(),
945                         excess_data: Vec::new()
946                 });
947                 // Disable nodes 1, 2, and 8 by requiring unknown feature bits
948                 let mut unknown_features = NodeFeatures::known();
949                 unknown_features.set_required_unknown_bits();
950                 add_or_update_node(&net_graph_msg_handler, &secp_ctx, node1_privkey, unknown_features.clone(), 1);
951                 add_or_update_node(&net_graph_msg_handler, &secp_ctx, node2_privkey, unknown_features.clone(), 1);
952                 add_or_update_node(&net_graph_msg_handler, &secp_ctx, node8_privkey, unknown_features.clone(), 1);
953
954                 // // If all nodes require some features we don't understand, route should fail
955                 // if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id, &net_graph_msg_handler, &node3, None, &Vec::new(), 100, 42, Arc::clone(&logger)) {
956                 //      assert_eq!(err, "Failed to find a path to the given destination");
957                 // } else { panic!(); }
958
959                 // If we specify a channel to node8, that overrides our local channel view and that gets used
960                 let our_chans = vec![channelmanager::ChannelDetails {
961                         channel_id: [0; 32],
962                         short_channel_id: Some(42),
963                         remote_network_id: node8.clone(),
964                         counterparty_features: InitFeatures::from_le_bytes(vec![0b11]),
965                         channel_value_satoshis: 0,
966                         user_id: 0,
967                         outbound_capacity_msat: 0,
968                         inbound_capacity_msat: 0,
969                         is_live: true,
970                 }];
971                 let route = get_route(&our_id, &net_graph_msg_handler.network_graph.read().unwrap(), &node3, Some(&our_chans), &Vec::new(), 100, 42, Arc::clone(&logger)).unwrap();
972                 assert_eq!(route.paths[0].len(), 2);
973
974                 assert_eq!(route.paths[0][0].pubkey, node8);
975                 assert_eq!(route.paths[0][0].short_channel_id, 42);
976                 assert_eq!(route.paths[0][0].fee_msat, 200);
977                 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 8) | 1);
978                 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
979                 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
980
981                 assert_eq!(route.paths[0][1].pubkey, node3);
982                 assert_eq!(route.paths[0][1].short_channel_id, 13);
983                 assert_eq!(route.paths[0][1].fee_msat, 100);
984                 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
985                 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags!(3));
986                 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags!(13));
987
988                 // Re-enable nodes 1, 2, and 8
989                 add_or_update_node(&net_graph_msg_handler, &secp_ctx, node1_privkey, NodeFeatures::from_le_bytes(id_to_feature_flags!(1)), 2);
990                 add_or_update_node(&net_graph_msg_handler, &secp_ctx, node2_privkey, NodeFeatures::from_le_bytes(id_to_feature_flags!(2)), 2);
991                 add_or_update_node(&net_graph_msg_handler, &secp_ctx, node8_privkey, NodeFeatures::from_le_bytes(id_to_feature_flags!(8)), 2);
992
993                 // Note that we don't test disabling node 3 and failing to route to it, as we (somewhat
994                 // naively) assume that the user checked the feature bits on the invoice, which override
995                 // the node_announcement.
996
997                 // Route to 1 via 2 and 3 because our channel to 1 is disabled
998                 let route = get_route(&our_id, &net_graph_msg_handler.network_graph.read().unwrap(), &node1, None, &Vec::new(), 100, 42, Arc::clone(&logger)).unwrap();
999                 assert_eq!(route.paths[0].len(), 3);
1000
1001                 assert_eq!(route.paths[0][0].pubkey, node2);
1002                 assert_eq!(route.paths[0][0].short_channel_id, 2);
1003                 assert_eq!(route.paths[0][0].fee_msat, 200);
1004                 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 8) | 1);
1005                 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags!(2));
1006                 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags!(2));
1007
1008                 assert_eq!(route.paths[0][1].pubkey, node3);
1009                 assert_eq!(route.paths[0][1].short_channel_id, 4);
1010                 assert_eq!(route.paths[0][1].fee_msat, 100);
1011                 assert_eq!(route.paths[0][1].cltv_expiry_delta, (3 << 8) | 2);
1012                 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags!(3));
1013                 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags!(4));
1014
1015                 assert_eq!(route.paths[0][2].pubkey, node1);
1016                 assert_eq!(route.paths[0][2].short_channel_id, 3);
1017                 assert_eq!(route.paths[0][2].fee_msat, 100);
1018                 assert_eq!(route.paths[0][2].cltv_expiry_delta, 42);
1019                 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags!(1));
1020                 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags!(3));
1021
1022                 // If we specify a channel to node8, that overrides our local channel view and that gets used
1023                 let our_chans = vec![channelmanager::ChannelDetails {
1024                         channel_id: [0; 32],
1025                         short_channel_id: Some(42),
1026                         remote_network_id: node8.clone(),
1027                         counterparty_features: InitFeatures::from_le_bytes(vec![0b11]),
1028                         channel_value_satoshis: 0,
1029                         user_id: 0,
1030                         outbound_capacity_msat: 0,
1031                         inbound_capacity_msat: 0,
1032                         is_live: true,
1033                 }];
1034                 let route = get_route(&our_id, &net_graph_msg_handler.network_graph.read().unwrap(), &node3, Some(&our_chans), &Vec::new(), 100, 42, Arc::clone(&logger)).unwrap();
1035                 assert_eq!(route.paths[0].len(), 2);
1036
1037                 assert_eq!(route.paths[0][0].pubkey, node8);
1038                 assert_eq!(route.paths[0][0].short_channel_id, 42);
1039                 assert_eq!(route.paths[0][0].fee_msat, 200);
1040                 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 8) | 1);
1041                 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]);
1042                 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
1043
1044                 assert_eq!(route.paths[0][1].pubkey, node3);
1045                 assert_eq!(route.paths[0][1].short_channel_id, 13);
1046                 assert_eq!(route.paths[0][1].fee_msat, 100);
1047                 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
1048                 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags!(3));
1049                 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags!(13));
1050
1051                 let zero_fees = RoutingFees {
1052                         base_msat: 0,
1053                         proportional_millionths: 0,
1054                 };
1055                 let mut last_hops = vec!(RouteHint {
1056                                 src_node_id: node4.clone(),
1057                                 short_channel_id: 8,
1058                                 fees: zero_fees,
1059                                 cltv_expiry_delta: (8 << 8) | 1,
1060                                 htlc_minimum_msat: 0,
1061                         }, RouteHint {
1062                                 src_node_id: node5.clone(),
1063                                 short_channel_id: 9,
1064                                 fees: RoutingFees {
1065                                         base_msat: 1001,
1066                                         proportional_millionths: 0,
1067                                 },
1068                                 cltv_expiry_delta: (9 << 8) | 1,
1069                                 htlc_minimum_msat: 0,
1070                         }, RouteHint {
1071                                 src_node_id: node6.clone(),
1072                                 short_channel_id: 10,
1073                                 fees: zero_fees,
1074                                 cltv_expiry_delta: (10 << 8) | 1,
1075                                 htlc_minimum_msat: 0,
1076                         });
1077
1078                 // Simple test across 2, 3, 5, and 4 via a last_hop channel
1079                 let route = get_route(&our_id, &net_graph_msg_handler.network_graph.read().unwrap(), &node7, None, &last_hops, 100, 42, Arc::clone(&logger)).unwrap();
1080                 assert_eq!(route.paths[0].len(), 5);
1081
1082                 assert_eq!(route.paths[0][0].pubkey, node2);
1083                 assert_eq!(route.paths[0][0].short_channel_id, 2);
1084                 assert_eq!(route.paths[0][0].fee_msat, 100);
1085                 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 8) | 1);
1086                 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags!(2));
1087                 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags!(2));
1088
1089                 assert_eq!(route.paths[0][1].pubkey, node3);
1090                 assert_eq!(route.paths[0][1].short_channel_id, 4);
1091                 assert_eq!(route.paths[0][1].fee_msat, 0);
1092                 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 8) | 1);
1093                 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags!(3));
1094                 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags!(4));
1095
1096                 assert_eq!(route.paths[0][2].pubkey, node5);
1097                 assert_eq!(route.paths[0][2].short_channel_id, 6);
1098                 assert_eq!(route.paths[0][2].fee_msat, 0);
1099                 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 8) | 1);
1100                 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags!(5));
1101                 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags!(6));
1102
1103                 assert_eq!(route.paths[0][3].pubkey, node4);
1104                 assert_eq!(route.paths[0][3].short_channel_id, 11);
1105                 assert_eq!(route.paths[0][3].fee_msat, 0);
1106                 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 8) | 1);
1107                 // If we have a peer in the node map, we'll use their features here since we don't have
1108                 // a way of figuring out their features from the invoice:
1109                 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags!(4));
1110                 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags!(11));
1111
1112                 assert_eq!(route.paths[0][4].pubkey, node7);
1113                 assert_eq!(route.paths[0][4].short_channel_id, 8);
1114                 assert_eq!(route.paths[0][4].fee_msat, 100);
1115                 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
1116                 assert_eq!(route.paths[0][4].node_features.le_flags(), &Vec::<u8>::new()); // We dont pass flags in from invoices yet
1117                 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
1118
1119                 // Simple test with outbound channel to 4 to test that last_hops and first_hops connect
1120                 let our_chans = vec![channelmanager::ChannelDetails {
1121                         channel_id: [0; 32],
1122                         short_channel_id: Some(42),
1123                         remote_network_id: node4.clone(),
1124                         counterparty_features: InitFeatures::from_le_bytes(vec![0b11]),
1125                         channel_value_satoshis: 0,
1126                         user_id: 0,
1127                         outbound_capacity_msat: 0,
1128                         inbound_capacity_msat: 0,
1129                         is_live: true,
1130                 }];
1131                 let route = get_route(&our_id, &net_graph_msg_handler.network_graph.read().unwrap(), &node7, Some(&our_chans), &last_hops, 100, 42, Arc::clone(&logger)).unwrap();
1132                 assert_eq!(route.paths[0].len(), 2);
1133
1134                 assert_eq!(route.paths[0][0].pubkey, node4);
1135                 assert_eq!(route.paths[0][0].short_channel_id, 42);
1136                 assert_eq!(route.paths[0][0].fee_msat, 0);
1137                 assert_eq!(route.paths[0][0].cltv_expiry_delta, (8 << 8) | 1);
1138                 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]);
1139                 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
1140
1141                 assert_eq!(route.paths[0][1].pubkey, node7);
1142                 assert_eq!(route.paths[0][1].short_channel_id, 8);
1143                 assert_eq!(route.paths[0][1].fee_msat, 100);
1144                 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
1145                 assert_eq!(route.paths[0][1].node_features.le_flags(), &Vec::<u8>::new()); // We dont pass flags in from invoices yet
1146                 assert_eq!(route.paths[0][1].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
1147
1148                 last_hops[0].fees.base_msat = 1000;
1149
1150                 // Revert to via 6 as the fee on 8 goes up
1151                 let route = get_route(&our_id, &net_graph_msg_handler.network_graph.read().unwrap(), &node7, None, &last_hops, 100, 42, Arc::clone(&logger)).unwrap();
1152                 assert_eq!(route.paths[0].len(), 4);
1153
1154                 assert_eq!(route.paths[0][0].pubkey, node2);
1155                 assert_eq!(route.paths[0][0].short_channel_id, 2);
1156                 assert_eq!(route.paths[0][0].fee_msat, 200); // fee increased as its % of value transferred across node
1157                 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 8) | 1);
1158                 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags!(2));
1159                 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags!(2));
1160
1161                 assert_eq!(route.paths[0][1].pubkey, node3);
1162                 assert_eq!(route.paths[0][1].short_channel_id, 4);
1163                 assert_eq!(route.paths[0][1].fee_msat, 100);
1164                 assert_eq!(route.paths[0][1].cltv_expiry_delta, (7 << 8) | 1);
1165                 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags!(3));
1166                 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags!(4));
1167
1168                 assert_eq!(route.paths[0][2].pubkey, node6);
1169                 assert_eq!(route.paths[0][2].short_channel_id, 7);
1170                 assert_eq!(route.paths[0][2].fee_msat, 0);
1171                 assert_eq!(route.paths[0][2].cltv_expiry_delta, (10 << 8) | 1);
1172                 // If we have a peer in the node map, we'll use their features here since we don't have
1173                 // a way of figuring out their features from the invoice:
1174                 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags!(6));
1175                 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags!(7));
1176
1177                 assert_eq!(route.paths[0][3].pubkey, node7);
1178                 assert_eq!(route.paths[0][3].short_channel_id, 10);
1179                 assert_eq!(route.paths[0][3].fee_msat, 100);
1180                 assert_eq!(route.paths[0][3].cltv_expiry_delta, 42);
1181                 assert_eq!(route.paths[0][3].node_features.le_flags(), &Vec::<u8>::new()); // We dont pass flags in from invoices yet
1182                 assert_eq!(route.paths[0][3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
1183
1184                 // ...but still use 8 for larger payments as 6 has a variable feerate
1185                 let route = get_route(&our_id, &net_graph_msg_handler.network_graph.read().unwrap(), &node7, None, &last_hops, 2000, 42, Arc::clone(&logger)).unwrap();
1186                 assert_eq!(route.paths[0].len(), 5);
1187
1188                 assert_eq!(route.paths[0][0].pubkey, node2);
1189                 assert_eq!(route.paths[0][0].short_channel_id, 2);
1190                 assert_eq!(route.paths[0][0].fee_msat, 3000);
1191                 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 8) | 1);
1192                 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags!(2));
1193                 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags!(2));
1194
1195                 assert_eq!(route.paths[0][1].pubkey, node3);
1196                 assert_eq!(route.paths[0][1].short_channel_id, 4);
1197                 assert_eq!(route.paths[0][1].fee_msat, 0);
1198                 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 8) | 1);
1199                 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags!(3));
1200                 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags!(4));
1201
1202                 assert_eq!(route.paths[0][2].pubkey, node5);
1203                 assert_eq!(route.paths[0][2].short_channel_id, 6);
1204                 assert_eq!(route.paths[0][2].fee_msat, 0);
1205                 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 8) | 1);
1206                 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags!(5));
1207                 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags!(6));
1208
1209                 assert_eq!(route.paths[0][3].pubkey, node4);
1210                 assert_eq!(route.paths[0][3].short_channel_id, 11);
1211                 assert_eq!(route.paths[0][3].fee_msat, 1000);
1212                 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 8) | 1);
1213                 // If we have a peer in the node map, we'll use their features here since we don't have
1214                 // a way of figuring out their features from the invoice:
1215                 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags!(4));
1216                 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags!(11));
1217
1218                 assert_eq!(route.paths[0][4].pubkey, node7);
1219                 assert_eq!(route.paths[0][4].short_channel_id, 8);
1220                 assert_eq!(route.paths[0][4].fee_msat, 2000);
1221                 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
1222                 assert_eq!(route.paths[0][4].node_features.le_flags(), &Vec::<u8>::new()); // We dont pass flags in from invoices yet
1223                 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
1224         }
1225 }