f - make PaymentClaimable report actual received amount not sender intended amount

Author: alecchendev

lightning/src/ln/channelmanager.rs

@@ -191,6 +191,9 @@ struct ClaimableHTLC {
 	cltv_expiry: u32,
 	/// The amount (in msats) of this MPP part
 	value: u64,
+	/// The amount (in msats) that the sender intended to be sent (used for
+	/// validating total MPP amount)
+	intended_value: u64,
 	onion_payload: OnionPayload,
 	timer_ticks: u8,
 	/// The sum total of all MPP parts
@@ -3232,7 +3235,7 @@ where
 							HTLCForwardInfo::AddHTLC(PendingAddHTLCInfo {
 								prev_short_channel_id, prev_htlc_id, prev_funding_outpoint, prev_user_channel_id,
 								forward_info: PendingHTLCInfo {
-									routing, incoming_shared_secret, payment_hash, outgoing_amt_msat, ..
+									routing, incoming_shared_secret, payment_hash, incoming_amt_msat, outgoing_amt_msat, ..
 								}
 							}) => {
 								let (cltv_expiry, onion_payload, payment_data, phantom_shared_secret) = match routing {
@@ -3254,7 +3257,8 @@ where
 										incoming_packet_shared_secret: incoming_shared_secret,
 										phantom_shared_secret,
 									},
-									value: outgoing_amt_msat,
+									value: incoming_amt_msat.unwrap_or(outgoing_amt_msat),
+									intended_value: outgoing_amt_msat,
 									timer_ticks: 0,
 									total_msat: if let Some(data) = &payment_data { data.total_msat } else { outgoing_amt_msat },
 									cltv_expiry,
@@ -3309,9 +3313,9 @@ where
 												continue
 											}
 										}
-										let mut total_value = claimable_htlc.value;
+										let mut total_value = claimable_htlc.intended_value;
 										for htlc in htlcs.iter() {
-											total_value += htlc.value;
+											total_value += htlc.intended_value;
 											match &htlc.onion_payload {
 												OnionPayload::Invoice { .. } => {
 													if htlc.total_msat != $payment_data.total_msat {
@@ -3326,7 +3330,7 @@ where
 										}
 										if total_value >= msgs::MAX_VALUE_MSAT {
 											fail_htlc!(claimable_htlc, payment_hash);
-										} else if total_value - claimable_htlc.value >= $payment_data.total_msat {
+										} else if total_value - claimable_htlc.intended_value >= $payment_data.total_msat {
 											log_trace!(self.logger, "Failing HTLC with payment_hash {} as payment is already claimable",
 												log_bytes!(payment_hash.0));
 											fail_htlc!(claimable_htlc, payment_hash);
@@ -3337,7 +3341,7 @@ where
 												receiver_node_id: Some(receiver_node_id),
 												payment_hash,
 												purpose: purpose(),
-												amount_msat: total_value,
+												amount_msat: htlcs.iter().map(|htlc| htlc.value).sum(),
 												via_channel_id: Some(prev_channel_id),
 												via_user_channel_id: Some(prev_user_channel_id),
 											});
@@ -3391,13 +3395,14 @@ where
 												}
 												match claimable_payments.claimable_htlcs.entry(payment_hash) {
 													hash_map::Entry::Vacant(e) => {
+														let amount_msat = claimable_htlc.value;
 														let purpose = events::PaymentPurpose::SpontaneousPayment(preimage);
 														e.insert((purpose.clone(), vec![claimable_htlc]));
 														let prev_channel_id = prev_funding_outpoint.to_channel_id();
 														new_events.push(events::Event::PaymentClaimable {
 															receiver_node_id: Some(receiver_node_id),
 															payment_hash,
-															amount_msat: outgoing_amt_msat,
+															amount_msat,
 															purpose,
 															via_channel_id: Some(prev_channel_id),
 															via_user_channel_id: Some(prev_user_channel_id),
@@ -6767,6 +6772,7 @@ impl Writeable for ClaimableHTLC {
 			(0, self.prev_hop, required),
 			(1, self.total_msat, required),
 			(2, self.value, required),
+			(3, self.intended_value, required),
 			(4, payment_data, option),
 			(6, self.cltv_expiry, required),
 			(8, keysend_preimage, option),
@@ -6779,6 +6785,7 @@ impl Readable for ClaimableHTLC {
 	fn read<R: Read>(reader: &mut R) -> Result<Self, DecodeError> {
 		let mut prev_hop = crate::util::ser::RequiredWrapper(None);
 		let mut value = 0;
+		let mut intended_value = None;
 		let mut payment_data: Option<msgs::FinalOnionHopData> = None;
 		let mut cltv_expiry = 0;
 		let mut total_msat = None;
@@ -6787,6 +6794,7 @@ impl Readable for ClaimableHTLC {
 			(0, prev_hop, required),
 			(1, total_msat, option),
 			(2, value, required),
+			(3, intended_value, option),
 			(4, payment_data, option),
 			(6, cltv_expiry, required),
 			(8, keysend_preimage, option)
@@ -6815,6 +6823,7 @@ impl Readable for ClaimableHTLC {
 			prev_hop: prev_hop.0.unwrap(),
 			timer_ticks: 0,
 			value,
+			intended_value: intended_value.unwrap_or(value),
 			total_msat: total_msat.unwrap(),
 			onion_payload,
 			cltv_expiry,

lightning/src/ln/functional_tests.rs

@@ -8016,7 +8016,7 @@ fn test_onion_value_mpp_set_calculation() {
 
 	// Second path
 	let ev = remove_first_msg_event_to_node(&expected_paths[1][0].node.get_our_node_id(), &mut events);
-	pass_along_path(&nodes[0], expected_paths[1], total_msat, our_payment_hash.clone(), Some(our_payment_secret), ev, true, None);
+	pass_along_path(&nodes[0], expected_paths[1], 101_000, our_payment_hash.clone(), Some(our_payment_secret), ev, true, None);
 
 	claim_payment_along_route(&nodes[0], expected_paths.as_slice(), false, our_payment_preimage);
 }