Rename routing::router::test_utils to ::bench_utils
[rust-lightning] / lightning / src / routing / scoring.rs
index 54400624dce63a30ec0e506bfc1c87800a6bac4a..66900f2ba43bce7553bd951754c7684f3b314910 100644 (file)
@@ -28,7 +28,7 @@
 //! # impl Logger for FakeLogger {
 //! #     fn log(&self, record: &Record) { unimplemented!() }
 //! # }
-//! # fn find_scored_route(payer: PublicKey, route_params: RouteParameters, network_graph: NetworkGraph) {
+//! # fn find_scored_route(payer: PublicKey, route_params: RouteParameters, network_graph: NetworkGraph<&FakeLogger>) {
 //! # let logger = FakeLogger {};
 //! #
 //! // Use the default channel penalties.
@@ -102,6 +102,12 @@ pub trait Score $(: $supertrait)* {
 
        /// Handles updating channel penalties after successfully routing along a path.
        fn payment_path_successful(&mut self, path: &[&RouteHop]);
+
+       /// Handles updating channel penalties after a probe over the given path failed.
+       fn probe_failed(&mut self, path: &[&RouteHop], short_channel_id: u64);
+
+       /// Handles updating channel penalties after a probe over the given path succeeded.
+       fn probe_successful(&mut self, path: &[&RouteHop]);
 }
 
 impl<S: Score, T: DerefMut<Target=S> $(+ $supertrait)*> Score for T {
@@ -118,6 +124,14 @@ impl<S: Score, T: DerefMut<Target=S> $(+ $supertrait)*> Score for T {
        fn payment_path_successful(&mut self, path: &[&RouteHop]) {
                self.deref_mut().payment_path_successful(path)
        }
+
+       fn probe_failed(&mut self, path: &[&RouteHop], short_channel_id: u64) {
+               self.deref_mut().probe_failed(path, short_channel_id)
+       }
+
+       fn probe_successful(&mut self, path: &[&RouteHop]) {
+               self.deref_mut().probe_successful(path)
+       }
 }
 } }
 
@@ -148,6 +162,7 @@ pub trait LockableScore<'a> {
 /// use the Persister to persist it.
 pub trait WriteableScore<'a>: LockableScore<'a> + Writeable {}
 
+#[cfg(not(c_bindings))]
 impl<'a, T> WriteableScore<'a> for T where T: LockableScore<'a> + Writeable {}
 
 /// (C-not exported)
@@ -173,12 +188,39 @@ pub struct MultiThreadedLockableScore<S: Score> {
        score: Mutex<S>,
 }
 #[cfg(c_bindings)]
-/// (C-not exported)
+/// A locked `MultiThreadedLockableScore`.
+pub struct MultiThreadedLockableScoreLock<'a, S: Score>(MutexGuard<'a, S>);
+#[cfg(c_bindings)]
+impl<'a, T: Score + 'a> Score for MultiThreadedLockableScoreLock<'a, T> {
+       fn channel_penalty_msat(&self, scid: u64, source: &NodeId, target: &NodeId, usage: ChannelUsage) -> u64 {
+               self.0.channel_penalty_msat(scid, source, target, usage)
+       }
+       fn payment_path_failed(&mut self, path: &[&RouteHop], short_channel_id: u64) {
+               self.0.payment_path_failed(path, short_channel_id)
+       }
+       fn payment_path_successful(&mut self, path: &[&RouteHop]) {
+               self.0.payment_path_successful(path)
+       }
+       fn probe_failed(&mut self, path: &[&RouteHop], short_channel_id: u64) {
+               self.0.probe_failed(path, short_channel_id)
+       }
+       fn probe_successful(&mut self, path: &[&RouteHop]) {
+               self.0.probe_successful(path)
+       }
+}
+#[cfg(c_bindings)]
+impl<'a, T: Score + 'a> Writeable for MultiThreadedLockableScoreLock<'a, T> {
+       fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
+               self.0.write(writer)
+       }
+}
+
+#[cfg(c_bindings)]
 impl<'a, T: Score + 'a> LockableScore<'a> for MultiThreadedLockableScore<T> {
-       type Locked = MutexGuard<'a, T>;
+       type Locked = MultiThreadedLockableScoreLock<'a, T>;
 
-       fn lock(&'a self) -> MutexGuard<'a, T> {
-               Mutex::lock(&self.score).unwrap()
+       fn lock(&'a self) -> MultiThreadedLockableScoreLock<'a, T> {
+               MultiThreadedLockableScoreLock(Mutex::lock(&self.score).unwrap())
        }
 }
 
@@ -207,7 +249,7 @@ impl<'a, S: Writeable> Writeable for MutexGuard<'a, S> {
 }
 
 /// Proposed use of a channel passed as a parameter to [`Score::channel_penalty_msat`].
-#[derive(Clone, Copy)]
+#[derive(Clone, Copy, Debug)]
 pub struct ChannelUsage {
        /// The amount to send through the channel, denominated in millisatoshis.
        pub amount_msat: u64,
@@ -241,6 +283,10 @@ impl Score for FixedPenaltyScorer {
        fn payment_path_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
 
        fn payment_path_successful(&mut self, _path: &[&RouteHop]) {}
+
+       fn probe_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
+
+       fn probe_successful(&mut self, _path: &[&RouteHop]) {}
 }
 
 impl Writeable for FixedPenaltyScorer {
@@ -293,7 +339,8 @@ pub type ProbabilisticScorer<G, L> = ProbabilisticScorerUsingTime::<G, L, Config
 /// Probabilistic [`Score`] implementation.
 ///
 /// (C-not exported) generally all users should use the [`ProbabilisticScorer`] type alias.
-pub struct ProbabilisticScorerUsingTime<G: Deref<Target = NetworkGraph>, L: Deref, T: Time> where L::Target: Logger {
+pub struct ProbabilisticScorerUsingTime<G: Deref<Target = NetworkGraph<L>>, L: Deref, T: Time>
+where L::Target: Logger {
        params: ProbabilisticScoringParameters,
        network_graph: G,
        logger: L,
@@ -305,13 +352,30 @@ pub struct ProbabilisticScorerUsingTime<G: Deref<Target = NetworkGraph>, L: Dere
 ///
 /// Used to configure base, liquidity, and amount penalties, the sum of which comprises the channel
 /// penalty (i.e., the amount in msats willing to be paid to avoid routing through the channel).
-#[derive(Clone, Copy)]
+///
+/// The penalty applied to any channel by the [`ProbabilisticScorer`] is the sum of each of the
+/// parameters here.
+#[derive(Clone)]
 pub struct ProbabilisticScoringParameters {
        /// A fixed penalty in msats to apply to each channel.
        ///
        /// Default value: 500 msat
        pub base_penalty_msat: u64,
 
+       /// A multiplier used with the payment amount to calculate a fixed penalty applied to each
+       /// channel, in excess of the [`base_penalty_msat`].
+       ///
+       /// The purpose of the amount penalty is to avoid having fees dominate the channel cost (i.e.,
+       /// fees plus penalty) for large payments. The penalty is computed as the product of this
+       /// multiplier and `2^30`ths of the payment amount.
+       ///
+       /// ie `base_penalty_amount_multiplier_msat * amount_msat / 2^30`
+       ///
+       /// Default value: 8,192 msat
+       ///
+       /// [`base_penalty_msat`]: Self::base_penalty_msat
+       pub base_penalty_amount_multiplier_msat: u64,
+
        /// A multiplier used in conjunction with the negative `log10` of the channel's success
        /// probability for a payment to determine the liquidity penalty.
        ///
@@ -350,7 +414,7 @@ pub struct ProbabilisticScoringParameters {
        /// multiplier and `2^20`ths of the payment amount, weighted by the negative `log10` of the
        /// success probability.
        ///
-       /// `-log10(success_probability) * amount_penalty_multiplier_msat * amount_msat / 2^20`
+       /// `-log10(success_probability) * liquidity_penalty_amount_multiplier_msat * amount_msat / 2^20`
        ///
        /// In practice, this means for 0.1 success probability (`-log10(0.1) == 1`) each `2^20`th of
        /// the amount will result in a penalty of the multiplier. And, as the success probability
@@ -359,7 +423,41 @@ pub struct ProbabilisticScoringParameters {
        /// fall below `1`.
        ///
        /// Default value: 256 msat
-       pub amount_penalty_multiplier_msat: u64,
+       pub liquidity_penalty_amount_multiplier_msat: u64,
+
+       /// Manual penalties used for the given nodes. Allows to set a particular penalty for a given
+       /// node. Note that a manual penalty of `u64::max_value()` means the node would not ever be
+       /// considered during path finding.
+       ///
+       /// (C-not exported)
+       pub manual_node_penalties: HashMap<NodeId, u64>,
+
+       /// This penalty is applied when `htlc_maximum_msat` is equal to or larger than half of the
+       /// channel's capacity, which makes us prefer nodes with a smaller `htlc_maximum_msat`. We
+       /// treat such nodes preferentially as this makes balance discovery attacks harder to execute,
+       /// thereby creating an incentive to restrict `htlc_maximum_msat` and improve privacy.
+       ///
+       /// Default value: 250 msat
+       pub anti_probing_penalty_msat: u64,
+
+       /// This penalty is applied when the amount we're attempting to send over a channel exceeds our
+       /// current estimate of the channel's available liquidity.
+       ///
+       /// Note that in this case all other penalties, including the
+       /// [`liquidity_penalty_multiplier_msat`] and [`liquidity_penalty_amount_multiplier_msat`]-based
+       /// penalties, as well as the [`base_penalty_msat`] and the [`anti_probing_penalty_msat`], if
+       /// applicable, are still included in the overall penalty.
+       ///
+       /// If you wish to avoid creating paths with such channels entirely, setting this to a value of
+       /// `u64::max_value()` will guarantee that.
+       ///
+       /// Default value: 1_0000_0000_000 msat (1 Bitcoin)
+       ///
+       /// [`liquidity_penalty_multiplier_msat`]: Self::liquidity_penalty_multiplier_msat
+       /// [`liquidity_penalty_amount_multiplier_msat`]: Self::liquidity_penalty_amount_multiplier_msat
+       /// [`base_penalty_msat`]: Self::base_penalty_msat
+       /// [`anti_probing_penalty_msat`]: Self::anti_probing_penalty_msat
+       pub considered_impossible_penalty_msat: u64,
 }
 
 /// Accounting for channel liquidity balance uncertainty.
@@ -389,7 +487,7 @@ struct DirectedChannelLiquidity<L: Deref<Target = u64>, T: Time, U: Deref<Target
        half_life: Duration,
 }
 
-impl<G: Deref<Target = NetworkGraph>, L: Deref, T: Time> ProbabilisticScorerUsingTime<G, L, T> where L::Target: Logger {
+impl<G: Deref<Target = NetworkGraph<L>>, L: Deref, T: Time> ProbabilisticScorerUsingTime<G, L, T> where L::Target: Logger {
        /// Creates a new scorer using the given scoring parameters for sending payments from a node
        /// through a network graph.
        pub fn new(params: ProbabilisticScoringParameters, network_graph: G, logger: L) -> Self {
@@ -433,6 +531,49 @@ impl<G: Deref<Target = NetworkGraph>, L: Deref, T: Time> ProbabilisticScorerUsin
                        }
                }
        }
+
+       /// Query the estimated minimum and maximum liquidity available for sending a payment over the
+       /// channel with `scid` towards the given `target` node.
+       pub fn estimated_channel_liquidity_range(&self, scid: u64, target: &NodeId) -> Option<(u64, u64)> {
+               let graph = self.network_graph.read_only();
+
+               if let Some(chan) = graph.channels().get(&scid) {
+                       if let Some(liq) = self.channel_liquidities.get(&scid) {
+                               if let Some((directed_info, source)) = chan.as_directed_to(target) {
+                                       let amt = directed_info.effective_capacity().as_msat();
+                                       let dir_liq = liq.as_directed(source, target, amt, self.params.liquidity_offset_half_life);
+                                       return Some((dir_liq.min_liquidity_msat(), dir_liq.max_liquidity_msat()));
+                               }
+                       }
+               }
+               None
+       }
+
+       /// Marks the node with the given `node_id` as banned, i.e.,
+       /// it will be avoided during path finding.
+       pub fn add_banned(&mut self, node_id: &NodeId) {
+               self.params.manual_node_penalties.insert(*node_id, u64::max_value());
+       }
+
+       /// Removes the node with the given `node_id` from the list of nodes to avoid.
+       pub fn remove_banned(&mut self, node_id: &NodeId) {
+               self.params.manual_node_penalties.remove(node_id);
+       }
+
+       /// Sets a manual penalty for the given node.
+       pub fn set_manual_penalty(&mut self, node_id: &NodeId, penalty: u64) {
+               self.params.manual_node_penalties.insert(*node_id, penalty);
+       }
+
+       /// Removes the node with the given `node_id` from the list of manual penalties.
+       pub fn remove_manual_penalty(&mut self, node_id: &NodeId) {
+               self.params.manual_node_penalties.remove(node_id);
+       }
+
+       /// Clears the list of manual penalties that are applied during path finding.
+       pub fn clear_manual_penalties(&mut self) {
+               self.params.manual_node_penalties = HashMap::new();
+       }
 }
 
 impl ProbabilisticScoringParameters {
@@ -440,9 +581,21 @@ impl ProbabilisticScoringParameters {
        fn zero_penalty() -> Self {
                Self {
                        base_penalty_msat: 0,
+                       base_penalty_amount_multiplier_msat: 0,
                        liquidity_penalty_multiplier_msat: 0,
                        liquidity_offset_half_life: Duration::from_secs(3600),
-                       amount_penalty_multiplier_msat: 0,
+                       liquidity_penalty_amount_multiplier_msat: 0,
+                       manual_node_penalties: HashMap::new(),
+                       anti_probing_penalty_msat: 0,
+                       considered_impossible_penalty_msat: 0,
+               }
+       }
+
+       /// Marks all nodes in the given list as banned, i.e.,
+       /// they will be avoided during path finding.
+       pub fn add_banned_from_list(&mut self, node_ids: Vec<NodeId>) {
+               for id in node_ids {
+                       self.manual_node_penalties.insert(id, u64::max_value());
                }
        }
 }
@@ -451,9 +604,13 @@ impl Default for ProbabilisticScoringParameters {
        fn default() -> Self {
                Self {
                        base_penalty_msat: 500,
+                       base_penalty_amount_multiplier_msat: 8192,
                        liquidity_penalty_multiplier_msat: 40_000,
                        liquidity_offset_half_life: Duration::from_secs(3600),
-                       amount_penalty_multiplier_msat: 256,
+                       liquidity_penalty_amount_multiplier_msat: 256,
+                       manual_node_penalties: HashMap::new(),
+                       anti_probing_penalty_msat: 250,
+                       considered_impossible_penalty_msat: 1_0000_0000_000,
                }
        }
 }
@@ -521,35 +678,31 @@ const PRECISION_LOWER_BOUND_DENOMINATOR: u64 = approx::LOWER_BITS_BOUND;
 
 /// The divisor used when computing the amount penalty.
 const AMOUNT_PENALTY_DIVISOR: u64 = 1 << 20;
+const BASE_AMOUNT_PENALTY_DIVISOR: u64 = 1 << 30;
 
 impl<L: Deref<Target = u64>, T: Time, U: Deref<Target = T>> DirectedChannelLiquidity<L, T, U> {
-       /// Returns a penalty for routing the given HTLC `amount_msat` through the channel in this
-       /// direction.
-       fn penalty_msat(&self, amount_msat: u64, params: ProbabilisticScoringParameters) -> u64 {
+       /// Returns a liquidity penalty for routing the given HTLC `amount_msat` through the channel in
+       /// this direction.
+       fn penalty_msat(&self, amount_msat: u64, params: &ProbabilisticScoringParameters) -> u64 {
                let max_liquidity_msat = self.max_liquidity_msat();
                let min_liquidity_msat = core::cmp::min(self.min_liquidity_msat(), max_liquidity_msat);
                if amount_msat <= min_liquidity_msat {
                        0
                } else if amount_msat >= max_liquidity_msat {
-                       if amount_msat > max_liquidity_msat {
-                               u64::max_value()
-                       } else if max_liquidity_msat != self.capacity_msat {
-                               // Avoid using the failed channel on retry.
-                               u64::max_value()
-                       } else {
-                               // Equivalent to hitting the else clause below with the amount equal to the
-                               // effective capacity and without any certainty on the liquidity upper bound.
-                               let negative_log10_times_2048 = NEGATIVE_LOG10_UPPER_BOUND * 2048;
-                               self.combined_penalty_msat(amount_msat, negative_log10_times_2048, params)
-                       }
+                       // Equivalent to hitting the else clause below with the amount equal to the effective
+                       // capacity and without any certainty on the liquidity upper bound, plus the
+                       // impossibility penalty.
+                       let negative_log10_times_2048 = NEGATIVE_LOG10_UPPER_BOUND * 2048;
+                       self.combined_penalty_msat(amount_msat, negative_log10_times_2048, params)
+                               .saturating_add(params.considered_impossible_penalty_msat)
                } else {
                        let numerator = (max_liquidity_msat - amount_msat).saturating_add(1);
                        let denominator = (max_liquidity_msat - min_liquidity_msat).saturating_add(1);
                        if amount_msat - min_liquidity_msat < denominator / PRECISION_LOWER_BOUND_DENOMINATOR {
                                // If the failure probability is < 1.5625% (as 1 - numerator/denominator < 1/64),
                                // don't bother trying to use the log approximation as it gets too noisy to be
-                               // particularly helpful, instead just round down to 0 and return the base penalty.
-                               params.base_penalty_msat
+                               // particularly helpful, instead just round down to 0.
+                               0
                        } else {
                                let negative_log10_times_2048 =
                                        approx::negative_log10_times_2048(numerator, denominator);
@@ -558,11 +711,11 @@ impl<L: Deref<Target = u64>, T: Time, U: Deref<Target = T>> DirectedChannelLiqui
                }
        }
 
-       /// Computes the liquidity and amount penalties and adds them to the base penalty.
+       /// Computes the liquidity penalty from the penalty multipliers.
        #[inline(always)]
        fn combined_penalty_msat(
                &self, amount_msat: u64, negative_log10_times_2048: u64,
-               params: ProbabilisticScoringParameters
+               params: &ProbabilisticScoringParameters
        ) -> u64 {
                let liquidity_penalty_msat = {
                        // Upper bound the liquidity penalty to ensure some channel is selected.
@@ -571,12 +724,10 @@ impl<L: Deref<Target = u64>, T: Time, U: Deref<Target = T>> DirectedChannelLiqui
                        (negative_log10_times_2048.saturating_mul(multiplier_msat) / 2048).min(max_penalty_msat)
                };
                let amount_penalty_msat = negative_log10_times_2048
-                       .saturating_mul(params.amount_penalty_multiplier_msat)
+                       .saturating_mul(params.liquidity_penalty_amount_multiplier_msat)
                        .saturating_mul(amount_msat) / 2048 / AMOUNT_PENALTY_DIVISOR;
 
-               params.base_penalty_msat
-                       .saturating_add(liquidity_penalty_msat)
-                       .saturating_add(amount_penalty_msat)
+               liquidity_penalty_msat.saturating_add(amount_penalty_msat)
        }
 
        /// Returns the lower bound of the channel liquidity balance in this direction.
@@ -650,16 +801,33 @@ impl<L: DerefMut<Target = u64>, T: Time, U: DerefMut<Target = T>> DirectedChanne
        }
 }
 
-impl<G: Deref<Target = NetworkGraph>, L: Deref, T: Time> Score for ProbabilisticScorerUsingTime<G, L, T> where L::Target: Logger {
+impl<G: Deref<Target = NetworkGraph<L>>, L: Deref, T: Time> Score for ProbabilisticScorerUsingTime<G, L, T> where L::Target: Logger {
        fn channel_penalty_msat(
                &self, short_channel_id: u64, source: &NodeId, target: &NodeId, usage: ChannelUsage
        ) -> u64 {
-               if let EffectiveCapacity::ExactLiquidity { liquidity_msat } = usage.effective_capacity {
-                       if usage.amount_msat > liquidity_msat {
-                               return u64::max_value();
-                       } else {
-                               return self.params.base_penalty_msat;
-                       };
+               if let Some(penalty) = self.params.manual_node_penalties.get(target) {
+                       return *penalty;
+               }
+
+               let base_penalty_msat = self.params.base_penalty_msat.saturating_add(
+                       self.params.base_penalty_amount_multiplier_msat
+                               .saturating_mul(usage.amount_msat) / BASE_AMOUNT_PENALTY_DIVISOR);
+
+               let mut anti_probing_penalty_msat = 0;
+               match usage.effective_capacity {
+                       EffectiveCapacity::ExactLiquidity { liquidity_msat } => {
+                               if usage.amount_msat > liquidity_msat {
+                                       return u64::max_value();
+                               } else {
+                                       return base_penalty_msat;
+                               }
+                       },
+                       EffectiveCapacity::Total { capacity_msat, htlc_maximum_msat: Some(htlc_maximum_msat) } => {
+                               if htlc_maximum_msat >= capacity_msat/2 {
+                                       anti_probing_penalty_msat = self.params.anti_probing_penalty_msat;
+                               }
+                       },
+                       _ => {},
                }
 
                let liquidity_offset_half_life = self.params.liquidity_offset_half_life;
@@ -670,7 +838,9 @@ impl<G: Deref<Target = NetworkGraph>, L: Deref, T: Time> Score for Probabilistic
                        .get(&short_channel_id)
                        .unwrap_or(&ChannelLiquidity::new())
                        .as_directed(source, target, capacity_msat, liquidity_offset_half_life)
-                       .penalty_msat(amount_msat, self.params)
+                       .penalty_msat(amount_msat, &self.params)
+                       .saturating_add(anti_probing_penalty_msat)
+                       .saturating_add(base_penalty_msat)
        }
 
        fn payment_path_failed(&mut self, path: &[&RouteHop], short_channel_id: u64) {
@@ -738,6 +908,14 @@ impl<G: Deref<Target = NetworkGraph>, L: Deref, T: Time> Score for Probabilistic
                        }
                }
        }
+
+       fn probe_failed(&mut self, path: &[&RouteHop], short_channel_id: u64) {
+               self.payment_path_failed(path, short_channel_id)
+       }
+
+       fn probe_successful(&mut self, path: &[&RouteHop]) {
+               self.payment_path_failed(path, u64::max_value())
+       }
 }
 
 mod approx {
@@ -1050,17 +1228,17 @@ mod approx {
        }
 }
 
-impl<G: Deref<Target = NetworkGraph>, L: Deref, T: Time> Writeable for ProbabilisticScorerUsingTime<G, L, T> where L::Target: Logger {
+impl<G: Deref<Target = NetworkGraph<L>>, L: Deref, T: Time> Writeable for ProbabilisticScorerUsingTime<G, L, T> where L::Target: Logger {
        #[inline]
        fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
                write_tlv_fields!(w, {
-                       (0, self.channel_liquidities, required)
+                       (0, self.channel_liquidities, required),
                });
                Ok(())
        }
 }
 
-impl<G: Deref<Target = NetworkGraph>, L: Deref, T: Time>
+impl<G: Deref<Target = NetworkGraph<L>>, L: Deref, T: Time>
 ReadableArgs<(ProbabilisticScoringParameters, G, L)> for ProbabilisticScorerUsingTime<G, L, T> where L::Target: Logger {
        #[inline]
        fn read<R: Read>(
@@ -1069,7 +1247,7 @@ ReadableArgs<(ProbabilisticScoringParameters, G, L)> for ProbabilisticScorerUsin
                let (params, network_graph, logger) = args;
                let mut channel_liquidities = HashMap::new();
                read_tlv_fields!(r, {
-                       (0, channel_liquidities, required)
+                       (0, channel_liquidities, required),
                });
                Ok(Self {
                        params,
@@ -1104,10 +1282,22 @@ impl<T: Time> Readable for ChannelLiquidity<T> {
                        (2, max_liquidity_offset_msat, required),
                        (4, duration_since_epoch, required),
                });
+               // On rust prior to 1.60 `Instant::duration_since` will panic if time goes backwards.
+               // We write `last_updated` as wallclock time even though its ultimately an `Instant` (which
+               // is a time from a monotonic clock usually represented as an offset against boot time).
+               // Thus, we have to construct an `Instant` by subtracting the difference in wallclock time
+               // from the one that was written. However, because `Instant` can panic if we construct one
+               // in the future, we must handle wallclock time jumping backwards, which we do by simply
+               // using `Instant::now()` in that case.
+               let wall_clock_now = T::duration_since_epoch();
+               let now = T::now();
+               let last_updated = if wall_clock_now > duration_since_epoch {
+                       now - (wall_clock_now - duration_since_epoch)
+               } else { now };
                Ok(Self {
                        min_liquidity_offset_msat,
                        max_liquidity_offset_msat,
-                       last_updated: T::now() - (T::duration_since_epoch() - duration_since_epoch),
+                       last_updated,
                })
        }
 }
@@ -1118,8 +1308,8 @@ mod tests {
        use util::time::Time;
        use util::time::tests::SinceEpoch;
 
-       use ln::features::{ChannelFeatures, NodeFeatures};
-       use ln::msgs::{ChannelAnnouncement, ChannelUpdate, OptionalField, UnsignedChannelAnnouncement, UnsignedChannelUpdate};
+       use ln::channelmanager;
+       use ln::msgs::{ChannelAnnouncement, ChannelUpdate, UnsignedChannelAnnouncement, UnsignedChannelUpdate};
        use routing::gossip::{EffectiveCapacity, NetworkGraph, NodeId};
        use routing::router::RouteHop;
        use routing::scoring::{ChannelUsage, Score};
@@ -1163,7 +1353,7 @@ mod tests {
        // `ProbabilisticScorer` tests
 
        /// A probabilistic scorer for testing with time that can be manually advanced.
-       type ProbabilisticScorer<'a> = ProbabilisticScorerUsingTime::<&'a NetworkGraph, &'a TestLogger, SinceEpoch>;
+       type ProbabilisticScorer<'a> = ProbabilisticScorerUsingTime::<&'a NetworkGraph<&'a TestLogger>, &'a TestLogger, SinceEpoch>;
 
        fn sender_privkey() -> SecretKey {
                SecretKey::from_slice(&[41; 32]).unwrap()
@@ -1191,9 +1381,9 @@ mod tests {
                NodeId::from_pubkey(&recipient_pubkey())
        }
 
-       fn network_graph() -> NetworkGraph {
+       fn network_graph(logger: &TestLogger) -> NetworkGraph<&TestLogger> {
                let genesis_hash = genesis_block(Network::Testnet).header.block_hash();
-               let mut network_graph = NetworkGraph::new(genesis_hash);
+               let mut network_graph = NetworkGraph::new(genesis_hash, logger);
                add_channel(&mut network_graph, 42, source_privkey(), target_privkey());
                add_channel(&mut network_graph, 43, target_privkey(), recipient_privkey());
 
@@ -1201,7 +1391,7 @@ mod tests {
        }
 
        fn add_channel(
-               network_graph: &mut NetworkGraph, short_channel_id: u64, node_1_key: SecretKey,
+               network_graph: &mut NetworkGraph<&TestLogger>, short_channel_id: u64, node_1_key: SecretKey,
                node_2_key: SecretKey
        ) {
                let genesis_hash = genesis_block(Network::Testnet).header.block_hash();
@@ -1209,7 +1399,7 @@ mod tests {
                let node_2_secret = &SecretKey::from_slice(&[40; 32]).unwrap();
                let secp_ctx = Secp256k1::new();
                let unsigned_announcement = UnsignedChannelAnnouncement {
-                       features: ChannelFeatures::known(),
+                       features: channelmanager::provided_channel_features(),
                        chain_hash: genesis_hash,
                        short_channel_id,
                        node_id_1: PublicKey::from_secret_key(&secp_ctx, &node_1_key),
@@ -1228,13 +1418,14 @@ mod tests {
                };
                let chain_source: Option<&::util::test_utils::TestChainSource> = None;
                network_graph.update_channel_from_announcement(
-                       &signed_announcement, &chain_source, &secp_ctx).unwrap();
+                       &signed_announcement, &chain_source).unwrap();
                update_channel(network_graph, short_channel_id, node_1_key, 0);
                update_channel(network_graph, short_channel_id, node_2_key, 1);
        }
 
        fn update_channel(
-               network_graph: &mut NetworkGraph, short_channel_id: u64, node_key: SecretKey, flags: u8
+               network_graph: &mut NetworkGraph<&TestLogger>, short_channel_id: u64, node_key: SecretKey,
+               flags: u8
        ) {
                let genesis_hash = genesis_block(Network::Testnet).header.block_hash();
                let secp_ctx = Secp256k1::new();
@@ -1245,7 +1436,7 @@ mod tests {
                        flags,
                        cltv_expiry_delta: 18,
                        htlc_minimum_msat: 0,
-                       htlc_maximum_msat: OptionalField::Present(1_000),
+                       htlc_maximum_msat: 1_000,
                        fee_base_msat: 1,
                        fee_proportional_millionths: 0,
                        excess_data: Vec::new(),
@@ -1255,32 +1446,32 @@ mod tests {
                        signature: secp_ctx.sign_ecdsa(&msghash, &node_key),
                        contents: unsigned_update,
                };
-               network_graph.update_channel(&signed_update, &secp_ctx).unwrap();
+               network_graph.update_channel(&signed_update).unwrap();
        }
 
        fn payment_path_for_amount(amount_msat: u64) -> Vec<RouteHop> {
                vec![
                        RouteHop {
                                pubkey: source_pubkey(),
-                               node_features: NodeFeatures::known(),
+                               node_features: channelmanager::provided_node_features(),
                                short_channel_id: 41,
-                               channel_features: ChannelFeatures::known(),
+                               channel_features: channelmanager::provided_channel_features(),
                                fee_msat: 1,
                                cltv_expiry_delta: 18,
                        },
                        RouteHop {
                                pubkey: target_pubkey(),
-                               node_features: NodeFeatures::known(),
+                               node_features: channelmanager::provided_node_features(),
                                short_channel_id: 42,
-                               channel_features: ChannelFeatures::known(),
+                               channel_features: channelmanager::provided_channel_features(),
                                fee_msat: 2,
                                cltv_expiry_delta: 18,
                        },
                        RouteHop {
                                pubkey: recipient_pubkey(),
-                               node_features: NodeFeatures::known(),
+                               node_features: channelmanager::provided_node_features(),
                                short_channel_id: 43,
-                               channel_features: ChannelFeatures::known(),
+                               channel_features: channelmanager::provided_channel_features(),
                                fee_msat: amount_msat,
                                cltv_expiry_delta: 18,
                        },
@@ -1291,7 +1482,7 @@ mod tests {
        fn liquidity_bounds_directed_from_lowest_node_id() {
                let logger = TestLogger::new();
                let last_updated = SinceEpoch::now();
-               let network_graph = network_graph();
+               let network_graph = network_graph(&logger);
                let params = ProbabilisticScoringParameters::default();
                let mut scorer = ProbabilisticScorer::new(params, &network_graph, &logger)
                        .with_channel(42,
@@ -1366,7 +1557,7 @@ mod tests {
        fn resets_liquidity_upper_bound_when_crossed_by_lower_bound() {
                let logger = TestLogger::new();
                let last_updated = SinceEpoch::now();
-               let network_graph = network_graph();
+               let network_graph = network_graph(&logger);
                let params = ProbabilisticScoringParameters::default();
                let mut scorer = ProbabilisticScorer::new(params, &network_graph, &logger)
                        .with_channel(42,
@@ -1424,7 +1615,7 @@ mod tests {
        fn resets_liquidity_lower_bound_when_crossed_by_upper_bound() {
                let logger = TestLogger::new();
                let last_updated = SinceEpoch::now();
-               let network_graph = network_graph();
+               let network_graph = network_graph(&logger);
                let params = ProbabilisticScoringParameters::default();
                let mut scorer = ProbabilisticScorer::new(params, &network_graph, &logger)
                        .with_channel(42,
@@ -1481,7 +1672,7 @@ mod tests {
        #[test]
        fn increased_penalty_nearing_liquidity_upper_bound() {
                let logger = TestLogger::new();
-               let network_graph = network_graph();
+               let network_graph = network_graph(&logger);
                let params = ProbabilisticScoringParameters {
                        liquidity_penalty_multiplier_msat: 1_000,
                        ..ProbabilisticScoringParameters::zero_penalty()
@@ -1493,20 +1684,20 @@ mod tests {
                let usage = ChannelUsage {
                        amount_msat: 1_024,
                        inflight_htlc_msat: 0,
-                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024_000 },
+                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024_000, htlc_maximum_msat: Some(1_000) },
                };
                assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 0);
                let usage = ChannelUsage { amount_msat: 10_240, ..usage };
                assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 0);
                let usage = ChannelUsage { amount_msat: 102_400, ..usage };
                assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 47);
-               let usage = ChannelUsage { amount_msat: 1_024_000, ..usage };
+               let usage = ChannelUsage { amount_msat: 1_023_999, ..usage };
                assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 2_000);
 
                let usage = ChannelUsage {
                        amount_msat: 128,
                        inflight_htlc_msat: 0,
-                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024 },
+                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024, htlc_maximum_msat: Some(1_000) },
                };
                assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 58);
                let usage = ChannelUsage { amount_msat: 256, ..usage };
@@ -1527,9 +1718,10 @@ mod tests {
        fn constant_penalty_outside_liquidity_bounds() {
                let logger = TestLogger::new();
                let last_updated = SinceEpoch::now();
-               let network_graph = network_graph();
+               let network_graph = network_graph(&logger);
                let params = ProbabilisticScoringParameters {
                        liquidity_penalty_multiplier_msat: 1_000,
+                       considered_impossible_penalty_msat: u64::max_value(),
                        ..ProbabilisticScoringParameters::zero_penalty()
                };
                let scorer = ProbabilisticScorer::new(params, &network_graph, &logger)
@@ -1543,7 +1735,7 @@ mod tests {
                let usage = ChannelUsage {
                        amount_msat: 39,
                        inflight_htlc_msat: 0,
-                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 100 },
+                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 100, htlc_maximum_msat: Some(1_000) },
                };
                assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 0);
                let usage = ChannelUsage { amount_msat: 50, ..usage };
@@ -1556,7 +1748,7 @@ mod tests {
        #[test]
        fn does_not_further_penalize_own_channel() {
                let logger = TestLogger::new();
-               let network_graph = network_graph();
+               let network_graph = network_graph(&logger);
                let params = ProbabilisticScoringParameters {
                        liquidity_penalty_multiplier_msat: 1_000,
                        ..ProbabilisticScoringParameters::zero_penalty()
@@ -1567,7 +1759,7 @@ mod tests {
                let usage = ChannelUsage {
                        amount_msat: 500,
                        inflight_htlc_msat: 0,
-                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_000 },
+                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_000, htlc_maximum_msat: Some(1_000) },
                };
                let failed_path = payment_path_for_amount(500);
                let successful_path = payment_path_for_amount(200);
@@ -1584,7 +1776,7 @@ mod tests {
        #[test]
        fn sets_liquidity_lower_bound_on_downstream_failure() {
                let logger = TestLogger::new();
-               let network_graph = network_graph();
+               let network_graph = network_graph(&logger);
                let params = ProbabilisticScoringParameters {
                        liquidity_penalty_multiplier_msat: 1_000,
                        ..ProbabilisticScoringParameters::zero_penalty()
@@ -1597,7 +1789,7 @@ mod tests {
                let usage = ChannelUsage {
                        amount_msat: 250,
                        inflight_htlc_msat: 0,
-                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_000 },
+                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_000, htlc_maximum_msat: Some(1_000) },
                };
                assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 128);
                let usage = ChannelUsage { amount_msat: 500, ..usage };
@@ -1618,9 +1810,10 @@ mod tests {
        #[test]
        fn sets_liquidity_upper_bound_on_failure() {
                let logger = TestLogger::new();
-               let network_graph = network_graph();
+               let network_graph = network_graph(&logger);
                let params = ProbabilisticScoringParameters {
                        liquidity_penalty_multiplier_msat: 1_000,
+                       considered_impossible_penalty_msat: u64::max_value(),
                        ..ProbabilisticScoringParameters::zero_penalty()
                };
                let mut scorer = ProbabilisticScorer::new(params, &network_graph, &logger);
@@ -1631,7 +1824,7 @@ mod tests {
                let usage = ChannelUsage {
                        amount_msat: 250,
                        inflight_htlc_msat: 0,
-                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_000 },
+                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_000, htlc_maximum_msat: Some(1_000) },
                };
                assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 128);
                let usage = ChannelUsage { amount_msat: 500, ..usage };
@@ -1652,7 +1845,7 @@ mod tests {
        #[test]
        fn reduces_liquidity_upper_bound_along_path_on_success() {
                let logger = TestLogger::new();
-               let network_graph = network_graph();
+               let network_graph = network_graph(&logger);
                let params = ProbabilisticScoringParameters {
                        liquidity_penalty_multiplier_msat: 1_000,
                        ..ProbabilisticScoringParameters::zero_penalty()
@@ -1665,7 +1858,7 @@ mod tests {
                let usage = ChannelUsage {
                        amount_msat: 250,
                        inflight_htlc_msat: 0,
-                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_000 },
+                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_000, htlc_maximum_msat: Some(1_000) },
                };
                let path = payment_path_for_amount(500);
 
@@ -1683,10 +1876,11 @@ mod tests {
        #[test]
        fn decays_liquidity_bounds_over_time() {
                let logger = TestLogger::new();
-               let network_graph = network_graph();
+               let network_graph = network_graph(&logger);
                let params = ProbabilisticScoringParameters {
                        liquidity_penalty_multiplier_msat: 1_000,
                        liquidity_offset_half_life: Duration::from_secs(10),
+                       considered_impossible_penalty_msat: u64::max_value(),
                        ..ProbabilisticScoringParameters::zero_penalty()
                };
                let mut scorer = ProbabilisticScorer::new(params, &network_graph, &logger);
@@ -1696,10 +1890,10 @@ mod tests {
                let usage = ChannelUsage {
                        amount_msat: 0,
                        inflight_htlc_msat: 0,
-                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024 },
+                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024, htlc_maximum_msat: Some(1_024) },
                };
                assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 0);
-               let usage = ChannelUsage { amount_msat: 1_024, ..usage };
+               let usage = ChannelUsage { amount_msat: 1_023, ..usage };
                assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 2_000);
 
                scorer.payment_path_failed(&payment_path_for_amount(768).iter().collect::<Vec<_>>(), 42);
@@ -1743,26 +1937,26 @@ mod tests {
                let usage = ChannelUsage { amount_msat: 1_023, ..usage };
                assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 2_000);
                let usage = ChannelUsage { amount_msat: 1_024, ..usage };
-               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 2_000);
+               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), u64::max_value());
 
                // Fully decay liquidity upper bound.
                SinceEpoch::advance(Duration::from_secs(10));
                let usage = ChannelUsage { amount_msat: 0, ..usage };
                assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 0);
                let usage = ChannelUsage { amount_msat: 1_024, ..usage };
-               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 2_000);
+               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), u64::max_value());
 
                SinceEpoch::advance(Duration::from_secs(10));
                let usage = ChannelUsage { amount_msat: 0, ..usage };
                assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 0);
                let usage = ChannelUsage { amount_msat: 1_024, ..usage };
-               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 2_000);
+               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), u64::max_value());
        }
 
        #[test]
        fn decays_liquidity_bounds_without_shift_overflow() {
                let logger = TestLogger::new();
-               let network_graph = network_graph();
+               let network_graph = network_graph(&logger);
                let params = ProbabilisticScoringParameters {
                        liquidity_penalty_multiplier_msat: 1_000,
                        liquidity_offset_half_life: Duration::from_secs(10),
@@ -1774,7 +1968,7 @@ mod tests {
                let usage = ChannelUsage {
                        amount_msat: 256,
                        inflight_htlc_msat: 0,
-                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024 },
+                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024, htlc_maximum_msat: Some(1_000) },
                };
                assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 125);
 
@@ -1793,7 +1987,7 @@ mod tests {
        #[test]
        fn restricts_liquidity_bounds_after_decay() {
                let logger = TestLogger::new();
-               let network_graph = network_graph();
+               let network_graph = network_graph(&logger);
                let params = ProbabilisticScoringParameters {
                        liquidity_penalty_multiplier_msat: 1_000,
                        liquidity_offset_half_life: Duration::from_secs(10),
@@ -1805,7 +1999,7 @@ mod tests {
                let usage = ChannelUsage {
                        amount_msat: 512,
                        inflight_htlc_msat: 0,
-                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024 },
+                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024, htlc_maximum_msat: Some(1_000) },
                };
 
                assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 300);
@@ -1837,19 +2031,20 @@ mod tests {
        #[test]
        fn restores_persisted_liquidity_bounds() {
                let logger = TestLogger::new();
-               let network_graph = network_graph();
+               let network_graph = network_graph(&logger);
                let params = ProbabilisticScoringParameters {
                        liquidity_penalty_multiplier_msat: 1_000,
                        liquidity_offset_half_life: Duration::from_secs(10),
+                       considered_impossible_penalty_msat: u64::max_value(),
                        ..ProbabilisticScoringParameters::zero_penalty()
                };
-               let mut scorer = ProbabilisticScorer::new(params, &network_graph, &logger);
+               let mut scorer = ProbabilisticScorer::new(params.clone(), &network_graph, &logger);
                let source = source_node_id();
                let target = target_node_id();
                let usage = ChannelUsage {
                        amount_msat: 500,
                        inflight_htlc_msat: 0,
-                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_000 },
+                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_000, htlc_maximum_msat: Some(1_000) },
                };
 
                scorer.payment_path_failed(&payment_path_for_amount(500).iter().collect::<Vec<_>>(), 42);
@@ -1873,19 +2068,20 @@ mod tests {
        #[test]
        fn decays_persisted_liquidity_bounds() {
                let logger = TestLogger::new();
-               let network_graph = network_graph();
+               let network_graph = network_graph(&logger);
                let params = ProbabilisticScoringParameters {
                        liquidity_penalty_multiplier_msat: 1_000,
                        liquidity_offset_half_life: Duration::from_secs(10),
+                       considered_impossible_penalty_msat: u64::max_value(),
                        ..ProbabilisticScoringParameters::zero_penalty()
                };
-               let mut scorer = ProbabilisticScorer::new(params, &network_graph, &logger);
+               let mut scorer = ProbabilisticScorer::new(params.clone(), &network_graph, &logger);
                let source = source_node_id();
                let target = target_node_id();
                let usage = ChannelUsage {
                        amount_msat: 500,
                        inflight_htlc_msat: 0,
-                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_000 },
+                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_000, htlc_maximum_msat: Some(1_000) },
                };
 
                scorer.payment_path_failed(&payment_path_for_amount(500).iter().collect::<Vec<_>>(), 42);
@@ -1913,7 +2109,7 @@ mod tests {
                // Shows the scores of "realistic" sends of 100k sats over channels of 1-10m sats (with a
                // 50k sat reserve).
                let logger = TestLogger::new();
-               let network_graph = network_graph();
+               let network_graph = network_graph(&logger);
                let params = ProbabilisticScoringParameters::default();
                let scorer = ProbabilisticScorer::new(params, &network_graph, &logger);
                let source = source_node_id();
@@ -1922,61 +2118,61 @@ mod tests {
                let usage = ChannelUsage {
                        amount_msat: 100_000_000,
                        inflight_htlc_msat: 0,
-                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 950_000_000 },
+                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 950_000_000, htlc_maximum_msat: Some(1_000) },
                };
-               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 3613);
+               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 4375);
                let usage = ChannelUsage {
-                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_950_000_000 }, ..usage
+                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_950_000_000, htlc_maximum_msat: Some(1_000) }, ..usage
                };
-               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 1977);
+               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 2739);
                let usage = ChannelUsage {
-                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 2_950_000_000 }, ..usage
+                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 2_950_000_000, htlc_maximum_msat: Some(1_000) }, ..usage
                };
-               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 1474);
+               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 2236);
                let usage = ChannelUsage {
-                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 3_950_000_000 }, ..usage
+                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 3_950_000_000, htlc_maximum_msat: Some(1_000) }, ..usage
                };
-               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 1223);
+               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 1985);
                let usage = ChannelUsage {
-                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 4_950_000_000 }, ..usage
+                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 4_950_000_000, htlc_maximum_msat: Some(1_000) }, ..usage
                };
-               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 877);
+               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 1639);
                let usage = ChannelUsage {
-                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 5_950_000_000 }, ..usage
+                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 5_950_000_000, htlc_maximum_msat: Some(1_000) }, ..usage
                };
-               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 845);
+               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 1607);
                let usage = ChannelUsage {
-                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 6_950_000_000 }, ..usage
+                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 6_950_000_000, htlc_maximum_msat: Some(1_000) }, ..usage
                };
-               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 500);
+               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 1262);
                let usage = ChannelUsage {
-                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 7_450_000_000 }, ..usage
+                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 7_450_000_000, htlc_maximum_msat: Some(1_000) }, ..usage
                };
-               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 500);
+               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 1262);
                let usage = ChannelUsage {
-                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 7_950_000_000 }, ..usage
+                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 7_950_000_000, htlc_maximum_msat: Some(1_000) }, ..usage
                };
-               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 500);
+               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 1262);
                let usage = ChannelUsage {
-                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 8_950_000_000 }, ..usage
+                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 8_950_000_000, htlc_maximum_msat: Some(1_000) }, ..usage
                };
-               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 500);
+               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 1262);
                let usage = ChannelUsage {
-                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 9_950_000_000 }, ..usage
+                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 9_950_000_000, htlc_maximum_msat: Some(1_000) }, ..usage
                };
-               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 500);
+               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 1262);
        }
 
        #[test]
        fn adds_base_penalty_to_liquidity_penalty() {
                let logger = TestLogger::new();
-               let network_graph = network_graph();
+               let network_graph = network_graph(&logger);
                let source = source_node_id();
                let target = target_node_id();
                let usage = ChannelUsage {
                        amount_msat: 128,
                        inflight_htlc_msat: 0,
-                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024 },
+                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024, htlc_maximum_msat: Some(1_000) },
                };
 
                let params = ProbabilisticScoringParameters {
@@ -1987,27 +2183,37 @@ mod tests {
                assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 58);
 
                let params = ProbabilisticScoringParameters {
-                       base_penalty_msat: 500, liquidity_penalty_multiplier_msat: 1_000, ..Default::default()
+                       base_penalty_msat: 500, liquidity_penalty_multiplier_msat: 1_000,
+                       anti_probing_penalty_msat: 0, ..Default::default()
                };
                let scorer = ProbabilisticScorer::new(params, &network_graph, &logger);
                assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 558);
+
+               let params = ProbabilisticScoringParameters {
+                       base_penalty_msat: 500, liquidity_penalty_multiplier_msat: 1_000,
+                       base_penalty_amount_multiplier_msat: (1 << 30),
+                       anti_probing_penalty_msat: 0, ..Default::default()
+               };
+
+               let scorer = ProbabilisticScorer::new(params, &network_graph, &logger);
+               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 558 + 128);
        }
 
        #[test]
        fn adds_amount_penalty_to_liquidity_penalty() {
                let logger = TestLogger::new();
-               let network_graph = network_graph();
+               let network_graph = network_graph(&logger);
                let source = source_node_id();
                let target = target_node_id();
                let usage = ChannelUsage {
                        amount_msat: 512_000,
                        inflight_htlc_msat: 0,
-                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024_000 },
+                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024_000, htlc_maximum_msat: Some(1_000) },
                };
 
                let params = ProbabilisticScoringParameters {
                        liquidity_penalty_multiplier_msat: 1_000,
-                       amount_penalty_multiplier_msat: 0,
+                       liquidity_penalty_amount_multiplier_msat: 0,
                        ..ProbabilisticScoringParameters::zero_penalty()
                };
                let scorer = ProbabilisticScorer::new(params, &network_graph, &logger);
@@ -2015,7 +2221,7 @@ mod tests {
 
                let params = ProbabilisticScoringParameters {
                        liquidity_penalty_multiplier_msat: 1_000,
-                       amount_penalty_multiplier_msat: 256,
+                       liquidity_penalty_amount_multiplier_msat: 256,
                        ..ProbabilisticScoringParameters::zero_penalty()
                };
                let scorer = ProbabilisticScorer::new(params, &network_graph, &logger);
@@ -2025,7 +2231,7 @@ mod tests {
        #[test]
        fn calculates_log10_without_overflowing_u64_max_value() {
                let logger = TestLogger::new();
-               let network_graph = network_graph();
+               let network_graph = network_graph(&logger);
                let source = source_node_id();
                let target = target_node_id();
                let usage = ChannelUsage {
@@ -2044,9 +2250,12 @@ mod tests {
 
        #[test]
        fn accounts_for_inflight_htlc_usage() {
-               let network_graph = network_graph();
                let logger = TestLogger::new();
-               let params = ProbabilisticScoringParameters::default();
+               let network_graph = network_graph(&logger);
+               let params = ProbabilisticScoringParameters {
+                       considered_impossible_penalty_msat: u64::max_value(),
+                       ..ProbabilisticScoringParameters::zero_penalty()
+               };
                let scorer = ProbabilisticScorer::new(params, &network_graph, &logger);
                let source = source_node_id();
                let target = target_node_id();
@@ -2054,7 +2263,7 @@ mod tests {
                let usage = ChannelUsage {
                        amount_msat: 750,
                        inflight_htlc_msat: 0,
-                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_000 },
+                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_000, htlc_maximum_msat: Some(1_000) },
                };
                assert_ne!(scorer.channel_penalty_msat(42, &source, &target, usage), u64::max_value());
 
@@ -2064,10 +2273,10 @@ mod tests {
 
        #[test]
        fn removes_uncertainity_when_exact_liquidity_known() {
-               let network_graph = network_graph();
                let logger = TestLogger::new();
+               let network_graph = network_graph(&logger);
                let params = ProbabilisticScoringParameters::default();
-               let scorer = ProbabilisticScorer::new(params, &network_graph, &logger);
+               let scorer = ProbabilisticScorer::new(params.clone(), &network_graph, &logger);
                let source = source_node_id();
                let target = target_node_id();
 
@@ -2085,4 +2294,49 @@ mod tests {
                let usage = ChannelUsage { amount_msat: 1_001, ..usage };
                assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), u64::max_value());
        }
+
+       #[test]
+       fn adds_anti_probing_penalty() {
+               let logger = TestLogger::new();
+               let network_graph = network_graph(&logger);
+               let source = source_node_id();
+               let target = target_node_id();
+               let params = ProbabilisticScoringParameters {
+                       anti_probing_penalty_msat: 500,
+                       ..ProbabilisticScoringParameters::zero_penalty()
+               };
+               let scorer = ProbabilisticScorer::new(params, &network_graph, &logger);
+
+               // Check we receive no penalty for a low htlc_maximum_msat.
+               let usage = ChannelUsage {
+                       amount_msat: 512_000,
+                       inflight_htlc_msat: 0,
+                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024_000, htlc_maximum_msat: Some(1_000) },
+               };
+               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 0);
+
+               // Check we receive anti-probing penalty for htlc_maximum_msat == channel_capacity.
+               let usage = ChannelUsage {
+                       amount_msat: 512_000,
+                       inflight_htlc_msat: 0,
+                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024_000, htlc_maximum_msat: Some(1_024_000) },
+               };
+               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 500);
+
+               // Check we receive anti-probing penalty for htlc_maximum_msat == channel_capacity/2.
+               let usage = ChannelUsage {
+                       amount_msat: 512_000,
+                       inflight_htlc_msat: 0,
+                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024_000, htlc_maximum_msat: Some(512_000) },
+               };
+               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 500);
+
+               // Check we receive no anti-probing penalty for htlc_maximum_msat == channel_capacity/2 - 1.
+               let usage = ChannelUsage {
+                       amount_msat: 512_000,
+                       inflight_htlc_msat: 0,
+                       effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024_000, htlc_maximum_msat: Some(511_999) },
+               };
+               assert_eq!(scorer.channel_penalty_msat(42, &source, &target, usage), 0);
+       }
 }