X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;ds=sidebyside;f=lightning%2Fsrc%2Frouting%2Frouter.rs;h=104f4c93c3871aca1f0e6f3af73a959e9c13001f;hb=d7a6d0d10db17f8c737bf3ad40e7b9f4343e60d8;hp=193fe35233408e0c20946139faa547f374951ab1;hpb=39c5bbc0bb3b69941a355250859dbadf1203a499;p=rust-lightning

diff --git a/lightning/src/routing/router.rs b/lightning/src/routing/router.rs
index 193fe352..104f4c93 100644
--- a/lightning/src/routing/router.rs
+++ b/lightning/src/routing/router.rs
@@ -90,6 +90,7 @@ pub trait Router {
 		&self, payer: &PublicKey, route_params: &RouteParameters,
 		first_hops: Option<&[&ChannelDetails]>, inflight_htlcs: InFlightHtlcs
 	) -> Result<Route, LightningError>;
+
 	/// Finds a [`Route`] for a payment between the given `payer` and a payee.
 	///
 	/// The `payee` and the payment's value are given in [`RouteParameters::payment_params`]
@@ -112,12 +113,12 @@ pub trait Router {
 /// [`find_route`].
 ///
 /// [`ScoreLookUp`]: crate::routing::scoring::ScoreLookUp
-pub struct ScorerAccountingForInFlightHtlcs<'a, SP: Sized, Sc: 'a + ScoreLookUp<ScoreParams = SP>, S: Deref<Target = Sc>> {
+pub struct ScorerAccountingForInFlightHtlcs<'a, S: Deref> where S::Target: ScoreLookUp {
 	scorer: S,
 	// Maps a channel's short channel id and its direction to the liquidity used up.
 	inflight_htlcs: &'a InFlightHtlcs,
 }
-impl<'a, SP: Sized, Sc: ScoreLookUp<ScoreParams = SP>, S: Deref<Target = Sc>> ScorerAccountingForInFlightHtlcs<'a, SP, Sc, S> {
+impl<'a, S: Deref> ScorerAccountingForInFlightHtlcs<'a, S> where S::Target: ScoreLookUp {
 	/// Initialize a new `ScorerAccountingForInFlightHtlcs`.
 	pub fn new(scorer: S, inflight_htlcs: &'a InFlightHtlcs) -> Self {
 		ScorerAccountingForInFlightHtlcs {
@@ -127,13 +128,8 @@ impl<'a, SP: Sized, Sc: ScoreLookUp<ScoreParams = SP>, S: Deref<Target = Sc>> Sc
 	}
 }
 
-#[cfg(c_bindings)]
-impl<'a, SP: Sized, Sc: ScoreLookUp<ScoreParams = SP>, S: Deref<Target = Sc>> Writeable for ScorerAccountingForInFlightHtlcs<'a, SP, Sc, S> {
-	fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> { self.scorer.write(writer) }
-}
-
-impl<'a, SP: Sized, Sc: 'a + ScoreLookUp<ScoreParams = SP>, S: Deref<Target = Sc>> ScoreLookUp for ScorerAccountingForInFlightHtlcs<'a, SP, Sc, S> {
-	type ScoreParams = Sc::ScoreParams;
+impl<'a, S: Deref> ScoreLookUp for ScorerAccountingForInFlightHtlcs<'a, S> where S::Target: ScoreLookUp {
+	type ScoreParams = <S::Target as ScoreLookUp>::ScoreParams;
 	fn channel_penalty_msat(&self, short_channel_id: u64, source: &NodeId, target: &NodeId, usage: ChannelUsage, score_params: &Self::ScoreParams) -> u64 {
 		if let Some(used_liquidity) = self.inflight_htlcs.used_liquidity_msat(
 			source, target, short_channel_id
@@ -1622,9 +1618,13 @@ where L::Target: Logger {
 			|info| info.features.supports_basic_mpp()))
 	} else { false };
 
-	log_trace!(logger, "Searching for a route from payer {} to {} {} MPP and {} first hops {}overriding the network graph", our_node_pubkey,
-		LoggedPayeePubkey(payment_params.payee.node_id()), if allow_mpp { "with" } else { "without" },
-		first_hops.map(|hops| hops.len()).unwrap_or(0), if first_hops.is_some() { "" } else { "not " });
+	let max_total_routing_fee_msat = route_params.max_total_routing_fee_msat.unwrap_or(u64::max_value());
+
+	log_trace!(logger, "Searching for a route from payer {} to {} {} MPP and {} first hops {}overriding the network graph with a fee limit of {} msat",
+		our_node_pubkey, LoggedPayeePubkey(payment_params.payee.node_id()),
+		if allow_mpp { "with" } else { "without" },
+		first_hops.map(|hops| hops.len()).unwrap_or(0), if first_hops.is_some() { "" } else { "not " },
+		max_total_routing_fee_msat);
 
 	// Step (1).
 	// Prepare the data we'll use for payee-to-payer search by
@@ -1788,9 +1788,9 @@ where L::Target: Logger {
 					#[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
 					let may_overpay_to_meet_path_minimum_msat =
 						((amount_to_transfer_over_msat < $candidate.htlc_minimum_msat() &&
-						  recommended_value_msat > $candidate.htlc_minimum_msat()) ||
+						  recommended_value_msat >= $candidate.htlc_minimum_msat()) ||
 						 (amount_to_transfer_over_msat < $next_hops_path_htlc_minimum_msat &&
-						  recommended_value_msat > $next_hops_path_htlc_minimum_msat));
+						  recommended_value_msat >= $next_hops_path_htlc_minimum_msat));
 
 					let payment_failed_on_this_channel = scid_opt.map_or(false,
 						|scid| payment_params.previously_failed_channels.contains(&scid));
@@ -1890,7 +1890,6 @@ where L::Target: Logger {
 							}
 
 							// Ignore hops if augmenting the current path to them would put us over `max_total_routing_fee_msat`
-							let max_total_routing_fee_msat = route_params.max_total_routing_fee_msat.unwrap_or(u64::max_value());
 							if total_fee_msat > max_total_routing_fee_msat {
 								if should_log_candidate {
 									log_trace!(logger, "Ignoring {} due to exceeding max total routing fee limit.", LoggedCandidateHop(&$candidate));
@@ -2454,6 +2453,9 @@ where L::Target: Logger {
 		// because we deterministically terminated the search due to low liquidity.
 		if !found_new_path && channel_saturation_pow_half != 0 {
 			channel_saturation_pow_half = 0;
+		} else if !found_new_path && hit_minimum_limit && already_collected_value_msat < final_value_msat && path_value_msat != recommended_value_msat {
+			log_trace!(logger, "Failed to collect enough value, but running again to collect extra paths with a potentially higher limit.");
+			path_value_msat = recommended_value_msat;
 		} else if already_collected_value_msat >= recommended_value_msat || !found_new_path {
 			log_trace!(logger, "Have now collected {} msat (seeking {} msat) in paths. Last path loop {} a new path.",
 				already_collected_value_msat, recommended_value_msat, if found_new_path { "found" } else { "did not find" });
@@ -2625,14 +2627,6 @@ where L::Target: Logger {
 	// Make sure we would never create a route with more paths than we allow.
 	debug_assert!(paths.len() <= payment_params.max_path_count.into());
 
-	// Make sure we would never create a route whose total fees exceed max_total_routing_fee_msat.
-	if let Some(max_total_routing_fee_msat) = route_params.max_total_routing_fee_msat {
-		if paths.iter().map(|p| p.fee_msat()).sum::<u64>() > max_total_routing_fee_msat {
-			return Err(LightningError{err: format!("Failed to find route that adheres to the maximum total fee limit of {}msat",
-				max_total_routing_fee_msat), action: ErrorAction::IgnoreError});
-		}
-	}
-
 	if let Some(node_features) = payment_params.payee.node_features() {
 		for path in paths.iter_mut() {
 			path.hops.last_mut().unwrap().node_features = node_features.clone();
@@ -2640,6 +2634,15 @@ where L::Target: Logger {
 	}
 
 	let route = Route { paths, route_params: Some(route_params.clone()) };
+
+	// Make sure we would never create a route whose total fees exceed max_total_routing_fee_msat.
+	if let Some(max_total_routing_fee_msat) = route_params.max_total_routing_fee_msat {
+		if route.get_total_fees() > max_total_routing_fee_msat {
+			return Err(LightningError{err: format!("Failed to find route that adheres to the maximum total fee limit of {}msat",
+				max_total_routing_fee_msat), action: ErrorAction::IgnoreError});
+		}
+	}
+
 	log_info!(logger, "Got route: {}", log_route!(route));
 	Ok(route)
 }
@@ -2828,7 +2831,7 @@ mod tests {
 
 	use bitcoin::hashes::Hash;
 	use bitcoin::network::constants::Network;
-	use bitcoin::blockdata::constants::genesis_block;
+	use bitcoin::blockdata::constants::ChainHash;
 	use bitcoin::blockdata::script::Builder;
 	use bitcoin::blockdata::opcodes;
 	use bitcoin::blockdata::transaction::TxOut;
@@ -2863,6 +2866,7 @@ mod tests {
 			inbound_scid_alias: None,
 			channel_value_satoshis: 0,
 			user_channel_id: 0,
+			balance_msat: 0,
 			outbound_capacity_msat,
 			next_outbound_htlc_limit_msat: outbound_capacity_msat,
 			next_outbound_htlc_minimum_msat: 0,
@@ -2958,7 +2962,7 @@ mod tests {
 
 		// Disable other paths
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 12,
 			timestamp: 2,
 			flags: 2, // to disable
@@ -2970,7 +2974,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 3,
 			timestamp: 2,
 			flags: 2, // to disable
@@ -2982,7 +2986,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 13,
 			timestamp: 2,
 			flags: 2, // to disable
@@ -2994,7 +2998,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 6,
 			timestamp: 2,
 			flags: 2, // to disable
@@ -3006,7 +3010,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 7,
 			timestamp: 2,
 			flags: 2, // to disable
@@ -3021,7 +3025,7 @@ mod tests {
 		// Check against amount_to_transfer_over_msat.
 		// Set minimal HTLC of 200_000_000 msat.
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 2,
 			timestamp: 3,
 			flags: 0,
@@ -3036,7 +3040,7 @@ mod tests {
 		// Second hop only allows to forward 199_999_999 at most, thus not allowing the first hop to
 		// be used.
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 4,
 			timestamp: 3,
 			flags: 0,
@@ -3059,7 +3063,7 @@ mod tests {
 
 		// Lift the restriction on the first hop.
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 2,
 			timestamp: 4,
 			flags: 0,
@@ -3091,7 +3095,7 @@ mod tests {
 		// One path allows transferring 35-40 sats, another one also allows 35-40 sats.
 		// Thus, they can't send 60 without overpaying.
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 2,
 			timestamp: 2,
 			flags: 0,
@@ -3103,7 +3107,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 12,
 			timestamp: 3,
 			flags: 0,
@@ -3117,7 +3121,7 @@ mod tests {
 
 		// Make 0 fee.
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 13,
 			timestamp: 2,
 			flags: 0,
@@ -3129,7 +3133,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 4,
 			timestamp: 2,
 			flags: 0,
@@ -3143,7 +3147,7 @@ mod tests {
 
 		// Disable other paths
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 1,
 			timestamp: 3,
 			flags: 2, // to disable
@@ -3168,7 +3172,7 @@ mod tests {
 		// Now, test that if there are 2 paths, a "cheaper" by fee path wouldn't be prioritized
 		// while taking even more fee to match htlc_minimum_msat.
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 12,
 			timestamp: 4,
 			flags: 0,
@@ -3180,7 +3184,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 2,
 			timestamp: 3,
 			flags: 0,
@@ -3192,7 +3196,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 4,
 			timestamp: 4,
 			flags: 0,
@@ -3223,6 +3227,67 @@ mod tests {
 		assert_eq!(fees, 5_000);
 	}
 
+	#[test]
+	fn htlc_minimum_recipient_overpay_test() {
+		let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
+		let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
+		let config = UserConfig::default();
+		let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
+		let scorer = ln_test_utils::TestScorer::new();
+		let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
+		let random_seed_bytes = keys_manager.get_secure_random_bytes();
+
+		// Route to node2 over a single path which requires overpaying the recipient themselves.
+
+		// First disable all paths except the us -> node1 -> node2 path
+		update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
+			short_channel_id: 13,
+			timestamp: 2,
+			flags: 3,
+			cltv_expiry_delta: 0,
+			htlc_minimum_msat: 0,
+			htlc_maximum_msat: 0,
+			fee_base_msat: 0,
+			fee_proportional_millionths: 0,
+			excess_data: Vec::new()
+		});
+
+		// Set channel 4 to free but with a high htlc_minimum_msat
+		update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
+			short_channel_id: 4,
+			timestamp: 2,
+			flags: 0,
+			cltv_expiry_delta: 0,
+			htlc_minimum_msat: 15_000,
+			htlc_maximum_msat: MAX_VALUE_MSAT,
+			fee_base_msat: 0,
+			fee_proportional_millionths: 0,
+			excess_data: Vec::new()
+		});
+
+		// Now check that we'll fail to find a path if we fail to find a path if the htlc_minimum
+		// is overrun. Note that the fees are actually calculated on 3*payment amount as that's
+		// what we try to find a route for, so this test only just happens to work out to exactly
+		// the fee limit.
+		let mut route_params = RouteParameters::from_payment_params_and_value(
+			payment_params.clone(), 5_000);
+		route_params.max_total_routing_fee_msat = Some(9_999);
+		if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
+			&route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
+			&Default::default(), &random_seed_bytes) {
+				assert_eq!(err, "Failed to find route that adheres to the maximum total fee limit of 9999msat");
+		} else { panic!(); }
+
+		let mut route_params = RouteParameters::from_payment_params_and_value(
+			payment_params.clone(), 5_000);
+		route_params.max_total_routing_fee_msat = Some(10_000);
+		let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
+			Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
+		assert_eq!(route.get_total_fees(), 10_000);
+	}
+
 	#[test]
 	fn disable_channels_test() {
 		let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
@@ -3234,7 +3299,7 @@ mod tests {
 
 		// // Disable channels 4 and 12 by flags=2
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 4,
 			timestamp: 2,
 			flags: 2, // to disable
@@ -3246,7 +3311,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 12,
 			timestamp: 2,
 			flags: 2, // to disable
@@ -3678,7 +3743,7 @@ mod tests {
 
 		// Disabling channels 6 & 7 by flags=2
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 6,
 			timestamp: 2,
 			flags: 2, // to disable
@@ -3690,7 +3755,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 7,
 			timestamp: 2,
 			flags: 2, // to disable
@@ -3752,7 +3817,7 @@ mod tests {
 
 		// Disabling channels 6 & 7 by flags=2
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 6,
 			timestamp: 2,
 			flags: 2, // to disable
@@ -3764,7 +3829,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 7,
 			timestamp: 2,
 			flags: 2, // to disable
@@ -4113,7 +4178,7 @@ mod tests {
 
 		// First disable all other paths.
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 2,
 			timestamp: 2,
 			flags: 2,
@@ -4125,7 +4190,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 12,
 			timestamp: 2,
 			flags: 2,
@@ -4140,7 +4205,7 @@ mod tests {
 		// Make the first channel (#1) very permissive,
 		// and we will be testing all limits on the second channel.
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 1,
 			timestamp: 2,
 			flags: 0,
@@ -4155,7 +4220,7 @@ mod tests {
 		// First, let's see if routing works if we have absolutely no idea about the available amount.
 		// In this case, it should be set to 250_000 sats.
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 3,
 			timestamp: 2,
 			flags: 0,
@@ -4194,7 +4259,7 @@ mod tests {
 		// Check that setting next_outbound_htlc_limit_msat in first_hops limits the channels.
 		// Disable channel #1 and use another first hop.
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 1,
 			timestamp: 3,
 			flags: 2,
@@ -4237,7 +4302,7 @@ mod tests {
 
 		// Enable channel #1 back.
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 1,
 			timestamp: 4,
 			flags: 0,
@@ -4252,7 +4317,7 @@ mod tests {
 
 		// Now let's see if routing works if we know only htlc_maximum_msat.
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 3,
 			timestamp: 3,
 			flags: 0,
@@ -4293,7 +4358,7 @@ mod tests {
 		// We can't change UTXO capacity on the fly, so we'll disable
 		// the existing channel and add another one with the capacity we need.
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 3,
 			timestamp: 4,
 			flags: 2,
@@ -4317,7 +4382,7 @@ mod tests {
 
 		add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 333);
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 333,
 			timestamp: 1,
 			flags: 0,
@@ -4329,7 +4394,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 333,
 			timestamp: 1,
 			flags: 1,
@@ -4367,7 +4432,7 @@ mod tests {
 
 		// Now let's see if routing chooses htlc_maximum_msat over UTXO capacity.
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 333,
 			timestamp: 6,
 			flags: 0,
@@ -4422,7 +4487,7 @@ mod tests {
 
 		// Disable other potential paths.
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 2,
 			timestamp: 2,
 			flags: 2,
@@ -4434,7 +4499,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 7,
 			timestamp: 2,
 			flags: 2,
@@ -4449,7 +4514,7 @@ mod tests {
 		// Limit capacities
 
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 12,
 			timestamp: 2,
 			flags: 0,
@@ -4461,7 +4526,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 13,
 			timestamp: 2,
 			flags: 0,
@@ -4474,7 +4539,7 @@ mod tests {
 		});
 
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 6,
 			timestamp: 2,
 			flags: 0,
@@ -4486,7 +4551,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 11,
 			timestamp: 2,
 			flags: 0,
@@ -4552,7 +4617,7 @@ mod tests {
 
 		// Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 1,
 			timestamp: 2,
 			flags: 0,
@@ -4564,7 +4629,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 3,
 			timestamp: 2,
 			flags: 0,
@@ -4665,7 +4730,7 @@ mod tests {
 
 		// Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 1,
 			timestamp: 2,
 			flags: 0,
@@ -4677,7 +4742,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 3,
 			timestamp: 2,
 			flags: 0,
@@ -4692,7 +4757,7 @@ mod tests {
 		// Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats
 		// (total limit 60).
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 12,
 			timestamp: 2,
 			flags: 0,
@@ -4704,7 +4769,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 13,
 			timestamp: 2,
 			flags: 0,
@@ -4719,7 +4784,7 @@ mod tests {
 		// Path via node1 is channels {2, 4}. Limit them to 200 and 180 sats
 		// (total capacity 180 sats).
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 2,
 			timestamp: 2,
 			flags: 0,
@@ -4731,7 +4796,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 4,
 			timestamp: 2,
 			flags: 0,
@@ -4852,7 +4917,7 @@ mod tests {
 
 		// Disable other potential paths.
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 2,
 			timestamp: 2,
 			flags: 2,
@@ -4864,7 +4929,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 7,
 			timestamp: 2,
 			flags: 2,
@@ -4878,7 +4943,7 @@ mod tests {
 
 		// Path via {node0, node2} is channels {1, 3, 5}.
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 1,
 			timestamp: 2,
 			flags: 0,
@@ -4890,7 +4955,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 3,
 			timestamp: 2,
 			flags: 0,
@@ -4905,7 +4970,7 @@ mod tests {
 		// Capacity of 200 sats because this channel will be used by 3rd path as well.
 		add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 5,
 			timestamp: 2,
 			flags: 0,
@@ -4921,7 +4986,7 @@ mod tests {
 		// Add 100 sats to the capacities of {12, 13}, because these channels
 		// are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 12,
 			timestamp: 2,
 			flags: 0,
@@ -4933,7 +4998,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 13,
 			timestamp: 2,
 			flags: 0,
@@ -4946,7 +5011,7 @@ mod tests {
 		});
 
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 6,
 			timestamp: 2,
 			flags: 0,
@@ -4958,7 +5023,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 11,
 			timestamp: 2,
 			flags: 0,
@@ -5027,7 +5092,7 @@ mod tests {
 
 		// Disable other potential paths.
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 2,
 			timestamp: 2,
 			flags: 2,
@@ -5039,7 +5104,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 7,
 			timestamp: 2,
 			flags: 2,
@@ -5053,7 +5118,7 @@ mod tests {
 
 		// Path via {node0, node2} is channels {1, 3, 5}.
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 1,
 			timestamp: 2,
 			flags: 0,
@@ -5065,7 +5130,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 3,
 			timestamp: 2,
 			flags: 0,
@@ -5080,7 +5145,7 @@ mod tests {
 		// Capacity of 200 sats because this channel will be used by 3rd path as well.
 		add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 5,
 			timestamp: 2,
 			flags: 0,
@@ -5096,7 +5161,7 @@ mod tests {
 		// Add 100 sats to the capacities of {12, 13}, because these channels
 		// are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 12,
 			timestamp: 2,
 			flags: 0,
@@ -5108,7 +5173,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 13,
 			timestamp: 2,
 			flags: 0,
@@ -5121,7 +5186,7 @@ mod tests {
 		});
 
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 6,
 			timestamp: 2,
 			flags: 0,
@@ -5133,7 +5198,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 11,
 			timestamp: 2,
 			flags: 0,
@@ -5198,7 +5263,7 @@ mod tests {
 
 		// Disable other potential paths.
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 2,
 			timestamp: 2,
 			flags: 2,
@@ -5211,7 +5276,7 @@ mod tests {
 		});
 
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 7,
 			timestamp: 2,
 			flags: 2,
@@ -5225,7 +5290,7 @@ mod tests {
 
 		// Path via {node0, node2} is channels {1, 3, 5}.
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 1,
 			timestamp: 2,
 			flags: 0,
@@ -5237,7 +5302,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 3,
 			timestamp: 2,
 			flags: 0,
@@ -5251,7 +5316,7 @@ mod tests {
 
 		add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 5,
 			timestamp: 2,
 			flags: 0,
@@ -5274,7 +5339,7 @@ mod tests {
 		// - fee for channel 6 is 150 sats
 		// Let's test this by enforcing these 2 conditions and removing other limits.
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 12,
 			timestamp: 2,
 			flags: 0,
@@ -5286,7 +5351,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 13,
 			timestamp: 2,
 			flags: 0,
@@ -5299,7 +5364,7 @@ mod tests {
 		});
 
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 6,
 			timestamp: 2,
 			flags: 0,
@@ -5311,7 +5376,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 11,
 			timestamp: 2,
 			flags: 0,
@@ -5400,7 +5465,7 @@ mod tests {
 		// we think we can only send up to 1 additional sat over the last-hop but refuse to as its
 		// under 5% of our payment amount.
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 1,
 			timestamp: 2,
 			flags: 0,
@@ -5412,7 +5477,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 2,
 			timestamp: 2,
 			flags: 0,
@@ -5424,7 +5489,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 4,
 			timestamp: 2,
 			flags: 0,
@@ -5436,7 +5501,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 13,
 			timestamp: 2,
 			flags: 0|2, // Channel disabled
@@ -5493,7 +5558,7 @@ mod tests {
 
 		// Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50);
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 1,
 			timestamp: 2,
 			flags: 0,
@@ -5505,7 +5570,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 3,
 			timestamp: 2,
 			flags: 0,
@@ -5519,7 +5584,7 @@ mod tests {
 
 		// Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats (total limit 60);
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 12,
 			timestamp: 2,
 			flags: 0,
@@ -5531,7 +5596,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 13,
 			timestamp: 2,
 			flags: 0,
@@ -5545,7 +5610,7 @@ mod tests {
 
 		// Path via node1 is channels {2, 4}. Limit them to 20 and 20 sats (total capacity 20 sats).
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 2,
 			timestamp: 2,
 			flags: 0,
@@ -5557,7 +5622,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 4,
 			timestamp: 2,
 			flags: 0,
@@ -5652,7 +5717,7 @@ mod tests {
 
 		add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 6,
 			timestamp: 1,
 			flags: 0,
@@ -5667,7 +5732,7 @@ mod tests {
 
 		add_channel(&gossip_sync, &secp_ctx, &privkeys[1], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 5,
 			timestamp: 1,
 			flags: 0,
@@ -5682,7 +5747,7 @@ mod tests {
 
 		add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 4,
 			timestamp: 1,
 			flags: 0,
@@ -5697,7 +5762,7 @@ mod tests {
 
 		add_channel(&gossip_sync, &secp_ctx, &privkeys[3], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 3,
 			timestamp: 1,
 			flags: 0,
@@ -5712,7 +5777,7 @@ mod tests {
 
 		add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 2,
 			timestamp: 1,
 			flags: 0,
@@ -5726,7 +5791,7 @@ mod tests {
 
 		add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 1,
 			timestamp: 1,
 			flags: 0,
@@ -5787,7 +5852,7 @@ mod tests {
 		// We modify the graph to set the htlc_maximum of channel 2 to below the value we wish to
 		// send.
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 2,
 			timestamp: 2,
 			flags: 0,
@@ -5800,7 +5865,7 @@ mod tests {
 		});
 
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 12,
 			timestamp: 2,
 			flags: 0,
@@ -5857,7 +5922,7 @@ mod tests {
 		// gets an htlc_maximum_msat of 80_000 and channel 4 an htlc_minimum_msat of 90_000. We
 		// then try to send 90_000.
 		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 2,
 			timestamp: 2,
 			flags: 0,
@@ -5869,7 +5934,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 4,
 			timestamp: 2,
 			flags: 0,
@@ -6409,7 +6474,7 @@ mod tests {
 		// Set the fee on channel 13 to 100% to match channel 4 giving us two equivalent paths (us
 		// -> node 7 -> node2 and us -> node 1 -> node 2) which we should balance over.
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 4,
 			timestamp: 2,
 			flags: 0,
@@ -6421,7 +6486,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 13,
 			timestamp: 2,
 			flags: 0,
@@ -7087,7 +7152,7 @@ mod tests {
 		add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[1],
 			ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 1,
 			timestamp: 1,
 			flags: 0,
@@ -7099,7 +7164,7 @@ mod tests {
 			excess_data: Vec::new()
 		});
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 1,
 			timestamp: 1,
 			flags: 1,
@@ -7520,7 +7585,7 @@ mod tests {
 
 		add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
 		update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
-			chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
 			short_channel_id: 6,
 			timestamp: 1,
 			flags: 0,
@@ -7627,6 +7692,203 @@ mod tests {
 		assert_eq!(route.paths.len(), 1);
 		assert_eq!(route.get_total_amount(), amt_msat);
 	}
+
+	#[test]
+	fn first_hop_preferred_over_hint() {
+		// Check that if we have a first hop to a peer we'd always prefer that over a route hint
+		// they gave us, but we'd still consider all subsequent hints if they are more attractive.
+		let secp_ctx = Secp256k1::new();
+		let logger = Arc::new(ln_test_utils::TestLogger::new());
+		let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
+		let gossip_sync = P2PGossipSync::new(Arc::clone(&network_graph), None, Arc::clone(&logger));
+		let scorer = ln_test_utils::TestScorer::new();
+		let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
+		let random_seed_bytes = keys_manager.get_secure_random_bytes();
+		let config = UserConfig::default();
+
+		let amt_msat = 1_000_000;
+		let (our_privkey, our_node_id, privkeys, nodes) = get_nodes(&secp_ctx);
+
+		add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[0],
+			ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
+		update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
+			short_channel_id: 1,
+			timestamp: 1,
+			flags: 0,
+			cltv_expiry_delta: 42,
+			htlc_minimum_msat: 1_000,
+			htlc_maximum_msat: 10_000_000,
+			fee_base_msat: 800,
+			fee_proportional_millionths: 0,
+			excess_data: Vec::new()
+		});
+		update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
+			short_channel_id: 1,
+			timestamp: 1,
+			flags: 1,
+			cltv_expiry_delta: 42,
+			htlc_minimum_msat: 1_000,
+			htlc_maximum_msat: 10_000_000,
+			fee_base_msat: 800,
+			fee_proportional_millionths: 0,
+			excess_data: Vec::new()
+		});
+
+		add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[1],
+			ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 2);
+		update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
+			short_channel_id: 2,
+			timestamp: 2,
+			flags: 0,
+			cltv_expiry_delta: 42,
+			htlc_minimum_msat: 1_000,
+			htlc_maximum_msat: 10_000_000,
+			fee_base_msat: 800,
+			fee_proportional_millionths: 0,
+			excess_data: Vec::new()
+		});
+		update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
+			chain_hash: ChainHash::using_genesis_block(Network::Testnet),
+			short_channel_id: 2,
+			timestamp: 2,
+			flags: 1,
+			cltv_expiry_delta: 42,
+			htlc_minimum_msat: 1_000,
+			htlc_maximum_msat: 10_000_000,
+			fee_base_msat: 800,
+			fee_proportional_millionths: 0,
+			excess_data: Vec::new()
+		});
+
+		let dest_node_id = nodes[2];
+
+		let route_hint = RouteHint(vec![RouteHintHop {
+			src_node_id: our_node_id,
+			short_channel_id: 44,
+			fees: RoutingFees {
+				base_msat: 234,
+				proportional_millionths: 0,
+			},
+			cltv_expiry_delta: 10,
+			htlc_minimum_msat: None,
+			htlc_maximum_msat: Some(5_000_000),
+		},
+		RouteHintHop {
+			src_node_id: nodes[0],
+			short_channel_id: 45,
+			fees: RoutingFees {
+				base_msat: 123,
+				proportional_millionths: 0,
+			},
+			cltv_expiry_delta: 10,
+			htlc_minimum_msat: None,
+			htlc_maximum_msat: None,
+		}]);
+
+		let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
+			.with_route_hints(vec![route_hint]).unwrap()
+			.with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
+		let route_params = RouteParameters::from_payment_params_and_value(
+			payment_params, amt_msat);
+
+		// First create an insufficient first hop for channel with SCID 1 and check we'd use the
+		// route hint.
+		let first_hop = get_channel_details(Some(1), nodes[0],
+			channelmanager::provided_init_features(&config), 999_999);
+		let first_hops = vec![first_hop];
+
+		let route = get_route(&our_node_id, &route_params.clone(), &network_graph.read_only(),
+			Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
+			&Default::default(), &random_seed_bytes).unwrap();
+		assert_eq!(route.paths.len(), 1);
+		assert_eq!(route.get_total_amount(), amt_msat);
+		assert_eq!(route.paths[0].hops.len(), 2);
+		assert_eq!(route.paths[0].hops[0].short_channel_id, 44);
+		assert_eq!(route.paths[0].hops[1].short_channel_id, 45);
+		assert_eq!(route.get_total_fees(), 123);
+
+		// Now check we would trust our first hop info, i.e., fail if we detect the route hint is
+		// for a first hop channel.
+		let mut first_hop = get_channel_details(Some(1), nodes[0], channelmanager::provided_init_features(&config), 999_999);
+		first_hop.outbound_scid_alias = Some(44);
+		let first_hops = vec![first_hop];
+
+		let route_res = get_route(&our_node_id, &route_params.clone(), &network_graph.read_only(),
+			Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
+			&Default::default(), &random_seed_bytes);
+		assert!(route_res.is_err());
+
+		// Finally check we'd use the first hop if has sufficient outbound capacity. But we'd stil
+		// use the cheaper second hop of the route hint.
+		let mut first_hop = get_channel_details(Some(1), nodes[0],
+			channelmanager::provided_init_features(&config), 10_000_000);
+		first_hop.outbound_scid_alias = Some(44);
+		let first_hops = vec![first_hop];
+
+		let route = get_route(&our_node_id, &route_params.clone(), &network_graph.read_only(),
+			Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
+			&Default::default(), &random_seed_bytes).unwrap();
+		assert_eq!(route.paths.len(), 1);
+		assert_eq!(route.get_total_amount(), amt_msat);
+		assert_eq!(route.paths[0].hops.len(), 2);
+		assert_eq!(route.paths[0].hops[0].short_channel_id, 1);
+		assert_eq!(route.paths[0].hops[1].short_channel_id, 45);
+		assert_eq!(route.get_total_fees(), 123);
+	}
+
+	#[test]
+	fn allow_us_being_first_hint() {
+		// Check that we consider a route hint even if we are the src of the first hop.
+		let secp_ctx = Secp256k1::new();
+		let logger = Arc::new(ln_test_utils::TestLogger::new());
+		let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
+		let scorer = ln_test_utils::TestScorer::new();
+		let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
+		let random_seed_bytes = keys_manager.get_secure_random_bytes();
+		let config = UserConfig::default();
+
+		let (_, our_node_id, _, nodes) = get_nodes(&secp_ctx);
+
+		let amt_msat = 1_000_000;
+		let dest_node_id = nodes[1];
+
+		let first_hop = get_channel_details(Some(1), nodes[0], channelmanager::provided_init_features(&config), 10_000_000);
+		let first_hops = vec![first_hop];
+
+		let route_hint = RouteHint(vec![RouteHintHop {
+			src_node_id: our_node_id,
+			short_channel_id: 44,
+			fees: RoutingFees {
+				base_msat: 123,
+				proportional_millionths: 0,
+			},
+			cltv_expiry_delta: 10,
+			htlc_minimum_msat: None,
+			htlc_maximum_msat: None,
+		}]);
+
+		let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
+			.with_route_hints(vec![route_hint]).unwrap()
+			.with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
+
+		let route_params = RouteParameters::from_payment_params_and_value(
+			payment_params, amt_msat);
+
+
+		let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
+			Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
+			&Default::default(), &random_seed_bytes).unwrap();
+
+		assert_eq!(route.paths.len(), 1);
+		assert_eq!(route.get_total_amount(), amt_msat);
+		assert_eq!(route.get_total_fees(), 0);
+		assert_eq!(route.paths[0].hops.len(), 1);
+
+		assert_eq!(route.paths[0].hops[0].short_channel_id, 44);
+	}
 }
 
 #[cfg(all(any(test, ldk_bench), not(feature = "no-std")))]
@@ -7712,6 +7974,7 @@ pub(crate) mod bench_utils {
 			outbound_scid_alias: None,
 			channel_value_satoshis: 10_000_000_000,
 			user_channel_id: 0,
+			balance_msat: 10_000_000_000,
 			outbound_capacity_msat: 10_000_000_000,
 			next_outbound_htlc_minimum_msat: 0,
 			next_outbound_htlc_limit_msat: 10_000_000_000,