Include rounded msat balances in Balance::ClaimableOnChannelClose

If we're gonna push users towards using `Balance` to determine
their current balances, we really need to provide more information,
including msat balances.

Here we add rounded-out msat balances to the pre-close balance
information

Author: TheBlueMatt

lightning/src/chain/channelmonitor.rs

@@ -629,6 +629,32 @@ pub enum Balance {
 		/// transaction fee) this value will be zero. For [`ChannelMonitor`]s created prior to LDK
 		/// 0.0.124, the channel is always treated as outbound (and thus this value is never zero).
 		transaction_fee_satoshis: u64,
+		/// The amount of millisatoshis which has been burned to fees from HTLCs which are outbound
+		/// from us and are related to a payment which was sent by us. This is the sum of the
+		/// millisatoshis part of all HTLCs which are otherwise represented by
+		/// [`Balance::MaybeTimeoutClaimableHTLC`] with their
+		/// [`Balance::MaybeTimeoutClaimableHTLC::outbound_payment`] flag set, as well as any dust
+		/// HTLCs which would otherwise be represented the same.
+		outbound_payment_htlc_rounded_msat: u64,
+		/// The amount of millisatoshis which has been burned to fees from HTLCs which are outbound
+		/// from us and are related to a forwarded HTLC. This is the sum of the millisatoshis part
+		/// of all HTLCs which are otherwise represented by [`Balance::MaybeTimeoutClaimableHTLC`]
+		/// with their [`Balance::MaybeTimeoutClaimableHTLC::outbound_payment`] flag *not* set, as
+		/// well as any dust HTLCs which would otherwise be represented the same.
+		outbound_forwarded_htlc_rounded_msat: u64,
+		/// The amount of millisatoshis which has been burned to fees from HTLCs which are inbound
+		/// to us and for which we know the preimage. This is the sum of the millisatoshis part of
+		/// all HTLCs which would be represented by [`Balance::ContentiousClaimable`] on channel
+		/// close, but who's current value is included in
+		/// [`Balance::ClaimableOnChannelClose::amount_satoshis`], as well as any dust HTLCs which
+		/// would otherwise be represented the same.
+		inbound_claiming_htlc_rounded_msat: u64,
+		/// The amount of millisatoshis which has been burned to fees from HTLCs which are inbound
+		/// to us and for which we do not know the preimage. This is the sum of the millisatoshis
+		/// part of all HTLCs which would be represented by [`Balance::MaybePreimageClaimableHTLC`]
+		/// on channel close, as well as any dust HTLCs which would otherwise be represented the
+		/// same.
+		inbound_htlc_rounded_msat: u64,
 	},
 	/// The channel has been closed, and the given balance is ours but awaiting confirmations until
 	/// we consider it spendable.
@@ -2314,10 +2340,17 @@ impl<Signer: EcdsaChannelSigner> ChannelMonitor<Signer> {
 		} else {
 			let mut claimable_inbound_htlc_value_sat = 0;
 			let mut nondust_htlc_count = 0;
+			let mut outbound_payment_htlc_rounded_msat = 0;
+			let mut outbound_forwarded_htlc_rounded_msat = 0;
+			let mut inbound_claiming_htlc_rounded_msat = 0;
+			let mut inbound_htlc_rounded_msat = 0;
 			for (htlc, _, source) in us.current_holder_commitment_tx.htlc_outputs.iter() {
 				if htlc.transaction_output_index.is_some() {
 					nondust_htlc_count += 1;
-				} else { continue; }
+				}
+				let rounded_value_msat = if htlc.transaction_output_index.is_none() {
+					htlc.amount_msat
+				} else { htlc.amount_msat % 1000 };
 				if htlc.offered {
 					let outbound_payment = match source {
 						None => {
@@ -2327,22 +2360,35 @@ impl<Signer: EcdsaChannelSigner> ChannelMonitor<Signer> {
 						Some(HTLCSource::PreviousHopData(_)) => false,
 						Some(HTLCSource::OutboundRoute { .. }) => true,
 					};
-					res.push(Balance::MaybeTimeoutClaimableHTLC {
-						amount_satoshis: htlc.amount_msat / 1000,
-						claimable_height: htlc.cltv_expiry,
-						payment_hash: htlc.payment_hash,
-						outbound_payment,
-					});
+					if outbound_payment {
+						outbound_payment_htlc_rounded_msat += rounded_value_msat;
+					} else {
+						outbound_forwarded_htlc_rounded_msat += rounded_value_msat;
+					}
+					if htlc.transaction_output_index.is_some() {
+						res.push(Balance::MaybeTimeoutClaimableHTLC {
+							amount_satoshis: htlc.amount_msat / 1000,
+							claimable_height: htlc.cltv_expiry,
+							payment_hash: htlc.payment_hash,
+							outbound_payment,
+						});
+					}
 				} else if us.payment_preimages.get(&htlc.payment_hash).is_some() {
-					claimable_inbound_htlc_value_sat += htlc.amount_msat / 1000;
+					inbound_claiming_htlc_rounded_msat += rounded_value_msat;
+					if htlc.transaction_output_index.is_some() {
+						claimable_inbound_htlc_value_sat += htlc.amount_msat / 1000;
+					}
 				} else {
-					// As long as the HTLC is still in our latest commitment state, treat
-					// it as potentially claimable, even if it has long-since expired.
-					res.push(Balance::MaybePreimageClaimableHTLC {
-						amount_satoshis: htlc.amount_msat / 1000,
-						expiry_height: htlc.cltv_expiry,
-						payment_hash: htlc.payment_hash,
-					});
+					inbound_htlc_rounded_msat += rounded_value_msat;
+					if htlc.transaction_output_index.is_some() {
+						// As long as the HTLC is still in our latest commitment state, treat
+						// it as potentially claimable, even if it has long-since expired.
+						res.push(Balance::MaybePreimageClaimableHTLC {
+							amount_satoshis: htlc.amount_msat / 1000,
+							expiry_height: htlc.cltv_expiry,
+							payment_hash: htlc.payment_hash,
+						});
+					}
 				}
 			}
 			res.push(Balance::ClaimableOnChannelClose {
@@ -2352,6 +2398,10 @@ impl<Signer: EcdsaChannelSigner> ChannelMonitor<Signer> {
 						us.current_holder_commitment_tx.feerate_per_kw, nondust_htlc_count,
 						us.onchain_tx_handler.channel_type_features())
 				} else { 0 },
+				outbound_payment_htlc_rounded_msat,
+				outbound_forwarded_htlc_rounded_msat,
+				inbound_claiming_htlc_rounded_msat,
+				inbound_htlc_rounded_msat,
 			});
 		}
 

lightning/src/ln/monitor_tests.rs

@@ -242,9 +242,19 @@ fn do_chanmon_claim_value_coop_close(anchors: bool) {
 	assert_eq!(vec![Balance::ClaimableOnChannelClose {
 			amount_satoshis: 1_000_000 - 1_000 - commitment_tx_fee - anchor_outputs_value,
 			transaction_fee_satoshis: commitment_tx_fee,
+			outbound_payment_htlc_rounded_msat: 0,
+			outbound_forwarded_htlc_rounded_msat: 0,
+			inbound_claiming_htlc_rounded_msat: 0,
+			inbound_htlc_rounded_msat: 0,
 		}],
 		nodes[0].chain_monitor.chain_monitor.get_monitor(funding_outpoint).unwrap().get_claimable_balances());
-	assert_eq!(vec![Balance::ClaimableOnChannelClose { amount_satoshis: 1_000, transaction_fee_satoshis: 0 }],
+	assert_eq!(vec![Balance::ClaimableOnChannelClose {
+			amount_satoshis: 1_000, transaction_fee_satoshis: 0,
+			outbound_payment_htlc_rounded_msat: 0,
+			outbound_forwarded_htlc_rounded_msat: 0,
+			inbound_claiming_htlc_rounded_msat: 0,
+			inbound_htlc_rounded_msat: 0,
+		}],
 		nodes[1].chain_monitor.chain_monitor.get_monitor(funding_outpoint).unwrap().get_claimable_balances());
 
 	nodes[0].node.close_channel(&chan_id, &nodes[1].node.get_our_node_id()).unwrap();
@@ -443,11 +453,19 @@ fn do_test_claim_value_force_close(anchors: bool, prev_commitment_tx: bool) {
 	assert_eq!(sorted_vec(vec![Balance::ClaimableOnChannelClose {
 			amount_satoshis: 1_000_000 - 3_000 - 4_000 - 1_000 - 3 - commitment_tx_fee - anchor_outputs_value,
 			transaction_fee_satoshis: commitment_tx_fee,
+			outbound_payment_htlc_rounded_msat: 3000,
+			outbound_forwarded_htlc_rounded_msat: 0,
+			inbound_claiming_htlc_rounded_msat: 0,
+			inbound_htlc_rounded_msat: 0,
 		}, sent_htlc_balance.clone(), sent_htlc_timeout_balance.clone()]),
 		sorted_vec(nodes[0].chain_monitor.chain_monitor.get_monitor(funding_outpoint).unwrap().get_claimable_balances()));
 	assert_eq!(sorted_vec(vec![Balance::ClaimableOnChannelClose {
 			amount_satoshis: 1_000,
 			transaction_fee_satoshis: 0,
+			outbound_payment_htlc_rounded_msat: 0,
+			outbound_forwarded_htlc_rounded_msat: 0,
+			inbound_claiming_htlc_rounded_msat: 0,
+			inbound_htlc_rounded_msat: 3000,
 		}, received_htlc_balance.clone(), received_htlc_timeout_balance.clone()]),
 		sorted_vec(nodes[1].chain_monitor.chain_monitor.get_monitor(funding_outpoint).unwrap().get_claimable_balances()));
 
@@ -495,6 +513,10 @@ fn do_test_claim_value_force_close(anchors: bool, prev_commitment_tx: bool) {
 				commitment_tx_fee - // The commitment transaction fee with two HTLC outputs
 				anchor_outputs_value, // The anchor outputs value in satoshis
 			transaction_fee_satoshis: commitment_tx_fee,
+			outbound_payment_htlc_rounded_msat: 3000,
+			outbound_forwarded_htlc_rounded_msat: 0,
+			inbound_claiming_htlc_rounded_msat: 0,
+			inbound_htlc_rounded_msat: 0,
 		}, sent_htlc_timeout_balance.clone()];
 	if !prev_commitment_tx {
 		a_expected_balances.push(sent_htlc_balance.clone());
@@ -504,6 +526,10 @@ fn do_test_claim_value_force_close(anchors: bool, prev_commitment_tx: bool) {
 	assert_eq!(vec![Balance::ClaimableOnChannelClose {
 			amount_satoshis: 1_000 + 3_000 + 4_000,
 			transaction_fee_satoshis: 0,
+			outbound_payment_htlc_rounded_msat: 0,
+			outbound_forwarded_htlc_rounded_msat: 0,
+			inbound_claiming_htlc_rounded_msat: 3000,
+			inbound_htlc_rounded_msat: 0,
 		}],
 		nodes[1].chain_monitor.chain_monitor.get_monitor(funding_outpoint).unwrap().get_claimable_balances());
 
@@ -987,12 +1013,20 @@ fn test_no_preimage_inbound_htlc_balances() {
 	assert_eq!(sorted_vec(vec![Balance::ClaimableOnChannelClose {
 			amount_satoshis: 1_000_000 - 500_000 - 10_000 - commitment_tx_fee,
 			transaction_fee_satoshis: commitment_tx_fee,
+			outbound_payment_htlc_rounded_msat: 0,
+			outbound_forwarded_htlc_rounded_msat: 0,
+			inbound_claiming_htlc_rounded_msat: 0,
+			inbound_htlc_rounded_msat: 0,
 		}, a_received_htlc_balance.clone(), a_sent_htlc_balance.clone()]),
 		sorted_vec(nodes[0].chain_monitor.chain_monitor.get_monitor(funding_outpoint).unwrap().get_claimable_balances()));
 
 	assert_eq!(sorted_vec(vec![Balance::ClaimableOnChannelClose {
 			amount_satoshis: 500_000 - 20_000,
 			transaction_fee_satoshis: 0,
+			outbound_payment_htlc_rounded_msat: 0,
+			outbound_forwarded_htlc_rounded_msat: 0,
+			inbound_claiming_htlc_rounded_msat: 0,
+			inbound_htlc_rounded_msat: 0,
 		}, b_received_htlc_balance.clone(), b_sent_htlc_balance.clone()]),
 		sorted_vec(nodes[1].chain_monitor.chain_monitor.get_monitor(funding_outpoint).unwrap().get_claimable_balances()));
 
@@ -1272,6 +1306,10 @@ fn do_test_revoked_counterparty_commitment_balances(anchors: bool, confirm_htlc_
 	assert_eq!(sorted_vec(vec![Balance::ClaimableOnChannelClose {
 			amount_satoshis: 100_000 - 5_000 - 4_000 - 3 - 2_000 + 3_000,
 			transaction_fee_satoshis: 0,
+			outbound_payment_htlc_rounded_msat: 3000,
+			outbound_forwarded_htlc_rounded_msat: 0,
+			inbound_claiming_htlc_rounded_msat: 0,
+			inbound_htlc_rounded_msat: 0,
 		}, Balance::MaybeTimeoutClaimableHTLC {
 			amount_satoshis: 2_000,
 			claimable_height: missing_htlc_cltv_timeout,
@@ -1826,6 +1864,10 @@ fn do_test_revoked_counterparty_aggregated_claims(anchors: bool) {
 	assert_eq!(sorted_vec(vec![Balance::ClaimableOnChannelClose {
 			amount_satoshis: 100_000 - 4_000 - 3_000,
 			transaction_fee_satoshis: 0,
+			outbound_payment_htlc_rounded_msat: 0,
+			outbound_forwarded_htlc_rounded_msat: 0,
+			inbound_claiming_htlc_rounded_msat: 0,
+			inbound_htlc_rounded_msat: 0,
 		}, Balance::MaybeTimeoutClaimableHTLC {
 			amount_satoshis: 4_000,
 			claimable_height: htlc_cltv_timeout,