Avoid storing a full FinalOnionHopData in OnionPayload::Invoice
[rust-lightning] / lightning / src / ln / channelmanager.rs
index df1ba36c7e447ef4df1e133338d73c5505a2b271..a28d6347332694af4dab7fc0737dd13a2a38c834 100644 (file)
@@ -159,20 +159,26 @@ pub(crate) struct HTLCPreviousHopData {
 }
 
 enum OnionPayload {
-       /// Contains a total_msat (which may differ from value if this is a Multi-Path Payment) and a
-       /// payment_secret which prevents path-probing attacks and can associate different HTLCs which
-       /// are part of the same payment.
-       Invoice(msgs::FinalOnionHopData),
+       /// Indicates this incoming onion payload is for the purpose of paying an invoice.
+       Invoice {
+               /// This is only here for backwards-compatibility in serialization, in the future it can be
+               /// removed, breaking clients running 0.0.106 and earlier.
+               _legacy_hop_data: msgs::FinalOnionHopData,
+       },
        /// Contains the payer-provided preimage.
        Spontaneous(PaymentPreimage),
 }
 
+/// HTLCs that are to us and can be failed/claimed by the user
 struct ClaimableHTLC {
        prev_hop: HTLCPreviousHopData,
        cltv_expiry: u32,
+       /// The amount (in msats) of this MPP part
        value: u64,
        onion_payload: OnionPayload,
        timer_ticks: u8,
+       /// The sum total of all MPP parts
+       total_msat: u64,
 }
 
 /// A payment identifier used to uniquely identify a payment to LDK.
@@ -1005,6 +1011,13 @@ pub struct ChannelDetails {
        /// conflict-avoidance policy, exactly this amount is not likely to be spendable. However, we
        /// should be able to spend nearly this amount.
        pub outbound_capacity_msat: u64,
+       /// The available outbound capacity for sending a single HTLC to the remote peer. This is
+       /// similar to [`ChannelDetails::outbound_capacity_msat`] but it may be further restricted by
+       /// the current state and per-HTLC limit(s). This is intended for use when routing, allowing us
+       /// to use a limit as close as possible to the HTLC limit we can currently send.
+       ///
+       /// See also [`ChannelDetails::balance_msat`] and [`ChannelDetails::outbound_capacity_msat`].
+       pub next_outbound_htlc_limit_msat: u64,
        /// The available inbound capacity for the remote peer to send HTLCs to us. This does not
        /// include any pending HTLCs which are not yet fully resolved (and, thus, whose balance is not
        /// available for inclusion in new inbound HTLCs).
@@ -1509,8 +1522,6 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
        ///
        /// Non-proportional fees are fixed according to our risk using the provided fee estimator.
        ///
-       /// panics if channel_value_satoshis is >= `MAX_FUNDING_SATOSHIS`!
-       ///
        /// Users need to notify the new ChannelManager when a new block is connected or
        /// disconnected using its `block_connected` and `block_disconnected` methods, starting
        /// from after `params.latest_hash`.
@@ -1670,8 +1681,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                        let channel_state = self.channel_state.lock().unwrap();
                        res.reserve(channel_state.by_id.len());
                        for (channel_id, channel) in channel_state.by_id.iter().filter(f) {
-                               let (inbound_capacity_msat, outbound_capacity_msat) = channel.get_inbound_outbound_available_balance_msat();
-                               let balance_msat = channel.get_balance_msat();
+                               let balance = channel.get_available_balances();
                                let (to_remote_reserve_satoshis, to_self_reserve_satoshis) =
                                        channel.get_holder_counterparty_selected_channel_reserve_satoshis();
                                res.push(ChannelDetails {
@@ -1698,9 +1708,10 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                        inbound_scid_alias: channel.latest_inbound_scid_alias(),
                                        channel_value_satoshis: channel.get_value_satoshis(),
                                        unspendable_punishment_reserve: to_self_reserve_satoshis,
-                                       balance_msat,
-                                       inbound_capacity_msat,
-                                       outbound_capacity_msat,
+                                       balance_msat: balance.balance_msat,
+                                       inbound_capacity_msat: balance.inbound_capacity_msat,
+                                       outbound_capacity_msat: balance.outbound_capacity_msat,
+                                       next_outbound_htlc_limit_msat: balance.next_outbound_htlc_limit_msat,
                                        user_channel_id: channel.get_user_id(),
                                        confirmations_required: channel.minimum_depth(),
                                        force_close_spend_delay: channel.get_counterparty_selected_contest_delay(),
@@ -3091,11 +3102,13 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                                        HTLCForwardInfo::AddHTLC { prev_short_channel_id, prev_htlc_id, forward_info: PendingHTLCInfo {
                                                                        routing, incoming_shared_secret, payment_hash, amt_to_forward, .. },
                                                                        prev_funding_outpoint } => {
-                                                               let (cltv_expiry, onion_payload, phantom_shared_secret) = match routing {
-                                                                       PendingHTLCRouting::Receive { payment_data, incoming_cltv_expiry, phantom_shared_secret } =>
-                                                                               (incoming_cltv_expiry, OnionPayload::Invoice(payment_data), phantom_shared_secret),
+                                                               let (cltv_expiry, onion_payload, payment_data, phantom_shared_secret) = match routing {
+                                                                       PendingHTLCRouting::Receive { payment_data, incoming_cltv_expiry, phantom_shared_secret } => {
+                                                                               let _legacy_hop_data = payment_data.clone();
+                                                                               (incoming_cltv_expiry, OnionPayload::Invoice { _legacy_hop_data }, Some(payment_data), phantom_shared_secret)
+                                                                       },
                                                                        PendingHTLCRouting::ReceiveKeysend { payment_preimage, incoming_cltv_expiry } =>
-                                                                               (incoming_cltv_expiry, OnionPayload::Spontaneous(payment_preimage), None),
+                                                                               (incoming_cltv_expiry, OnionPayload::Spontaneous(payment_preimage), None, None),
                                                                        _ => {
                                                                                panic!("short_channel_id == 0 should imply any pending_forward entries are of type Receive");
                                                                        }
@@ -3110,6 +3123,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                                                        },
                                                                        value: amt_to_forward,
                                                                        timer_ticks: 0,
+                                                                       total_msat: if let Some(data) = &payment_data { data.total_msat } else { amt_to_forward },
                                                                        cltv_expiry,
                                                                        onion_payload,
                                                                };
@@ -3133,7 +3147,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                                                }
 
                                                                macro_rules! check_total_value {
-                                                                       ($payment_data_total_msat: expr, $payment_secret: expr, $payment_preimage: expr) => {{
+                                                                       ($payment_data: expr, $payment_preimage: expr) => {{
                                                                                let mut payment_received_generated = false;
                                                                                let htlcs = channel_state.claimable_htlcs.entry(payment_hash)
                                                                                        .or_insert(Vec::new());
@@ -3148,10 +3162,10 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                                                                for htlc in htlcs.iter() {
                                                                                        total_value += htlc.value;
                                                                                        match &htlc.onion_payload {
-                                                                                               OnionPayload::Invoice(htlc_payment_data) => {
-                                                                                                       if htlc_payment_data.total_msat != $payment_data_total_msat {
+                                                                                               OnionPayload::Invoice { .. } => {
+                                                                                                       if htlc.total_msat != $payment_data.total_msat {
                                                                                                                log_trace!(self.logger, "Failing HTLCs with payment_hash {} as the HTLCs had inconsistent total values (eg {} and {})",
-                                                                                                                       log_bytes!(payment_hash.0), $payment_data_total_msat, htlc_payment_data.total_msat);
+                                                                                                                       log_bytes!(payment_hash.0), $payment_data.total_msat, htlc.total_msat);
                                                                                                                total_value = msgs::MAX_VALUE_MSAT;
                                                                                                        }
                                                                                                        if total_value >= msgs::MAX_VALUE_MSAT { break; }
@@ -3159,17 +3173,17 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                                                                                _ => unreachable!(),
                                                                                        }
                                                                                }
-                                                                               if total_value >= msgs::MAX_VALUE_MSAT || total_value > $payment_data_total_msat {
+                                                                               if total_value >= msgs::MAX_VALUE_MSAT || total_value > $payment_data.total_msat {
                                                                                        log_trace!(self.logger, "Failing HTLCs with payment_hash {} as the total value {} ran over expected value {} (or HTLCs were inconsistent)",
-                                                                                               log_bytes!(payment_hash.0), total_value, $payment_data_total_msat);
+                                                                                               log_bytes!(payment_hash.0), total_value, $payment_data.total_msat);
                                                                                        fail_htlc!(claimable_htlc);
-                                                                               } else if total_value == $payment_data_total_msat {
+                                                                               } else if total_value == $payment_data.total_msat {
                                                                                        htlcs.push(claimable_htlc);
                                                                                        new_events.push(events::Event::PaymentReceived {
                                                                                                payment_hash,
                                                                                                purpose: events::PaymentPurpose::InvoicePayment {
                                                                                                        payment_preimage: $payment_preimage,
-                                                                                                       payment_secret: $payment_secret,
+                                                                                                       payment_secret: $payment_data.payment_secret,
                                                                                                },
                                                                                                amt: total_value,
                                                                                        });
@@ -3194,17 +3208,16 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                                                match payment_secrets.entry(payment_hash) {
                                                                        hash_map::Entry::Vacant(_) => {
                                                                                match claimable_htlc.onion_payload {
-                                                                                       OnionPayload::Invoice(ref payment_data) => {
-                                                                                               let payment_preimage = match inbound_payment::verify(payment_hash, payment_data.clone(), self.highest_seen_timestamp.load(Ordering::Acquire) as u64, &self.inbound_payment_key, &self.logger) {
+                                                                                       OnionPayload::Invoice { .. } => {
+                                                                                               let payment_data = payment_data.unwrap();
+                                                                                               let payment_preimage = match inbound_payment::verify(payment_hash, &payment_data, self.highest_seen_timestamp.load(Ordering::Acquire) as u64, &self.inbound_payment_key, &self.logger) {
                                                                                                        Ok(payment_preimage) => payment_preimage,
                                                                                                        Err(()) => {
                                                                                                                fail_htlc!(claimable_htlc);
                                                                                                                continue
                                                                                                        }
                                                                                                };
-                                                                                               let payment_data_total_msat = payment_data.total_msat;
-                                                                                               let payment_secret = payment_data.payment_secret.clone();
-                                                                                               check_total_value!(payment_data_total_msat, payment_secret, payment_preimage);
+                                                                                               check_total_value!(payment_data, payment_preimage);
                                                                                        },
                                                                                        OnionPayload::Spontaneous(preimage) => {
                                                                                                match channel_state.claimable_htlcs.entry(payment_hash) {
@@ -3225,14 +3238,12 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                                                                }
                                                                        },
                                                                        hash_map::Entry::Occupied(inbound_payment) => {
-                                                                               let payment_data =
-                                                                                       if let OnionPayload::Invoice(ref data) = claimable_htlc.onion_payload {
-                                                                                               data.clone()
-                                                                                       } else {
-                                                                                               log_trace!(self.logger, "Failing new keysend HTLC with payment_hash {} because we already have an inbound payment with the same payment hash", log_bytes!(payment_hash.0));
-                                                                                               fail_htlc!(claimable_htlc);
-                                                                                               continue
-                                                                                       };
+                                                                               if payment_data.is_none() {
+                                                                                       log_trace!(self.logger, "Failing new keysend HTLC with payment_hash {} because we already have an inbound payment with the same payment hash", log_bytes!(payment_hash.0));
+                                                                                       fail_htlc!(claimable_htlc);
+                                                                                       continue
+                                                                               };
+                                                                               let payment_data = payment_data.unwrap();
                                                                                if inbound_payment.get().payment_secret != payment_data.payment_secret {
                                                                                        log_trace!(self.logger, "Failing new HTLC with payment_hash {} as it didn't match our expected payment secret.", log_bytes!(payment_hash.0));
                                                                                        fail_htlc!(claimable_htlc);
@@ -3241,7 +3252,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                                                                                log_bytes!(payment_hash.0), payment_data.total_msat, inbound_payment.get().min_value_msat.unwrap());
                                                                                        fail_htlc!(claimable_htlc);
                                                                                } else {
-                                                                                       let payment_received_generated = check_total_value!(payment_data.total_msat, payment_data.payment_secret, inbound_payment.get().payment_preimage);
+                                                                                       let payment_received_generated = check_total_value!(payment_data, inbound_payment.get().payment_preimage);
                                                                                        if payment_received_generated {
                                                                                                inbound_payment.remove_entry();
                                                                                        }
@@ -3460,10 +3471,10 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                                debug_assert!(false);
                                                return false;
                                        }
-                                       if let OnionPayload::Invoice(ref final_hop_data) = htlcs[0].onion_payload {
+                                       if let OnionPayload::Invoice { .. } = htlcs[0].onion_payload {
                                                // Check if we've received all the parts we need for an MPP (the value of the parts adds to total_msat).
                                                // In this case we're not going to handle any timeouts of the parts here.
-                                               if final_hop_data.total_msat == htlcs.iter().fold(0, |total, htlc| total + htlc.value) {
+                                               if htlcs[0].total_msat == htlcs.iter().fold(0, |total, htlc| total + htlc.value) {
                                                        return true;
                                                } else if htlcs.into_iter().any(|htlc| {
                                                        htlc.timer_ticks += 1;
@@ -5936,6 +5947,9 @@ impl_writeable_tlv_based!(ChannelDetails, {
        (14, user_channel_id, required),
        (16, balance_msat, required),
        (18, outbound_capacity_msat, required),
+       // Note that by the time we get past the required read above, outbound_capacity_msat will be
+       // filled in, so we can safely unwrap it here.
+       (19, next_outbound_htlc_limit_msat, (default_value, outbound_capacity_msat.0.unwrap())),
        (20, inbound_capacity_msat, required),
        (22, confirmations_required, option),
        (24, force_close_spend_delay, option),
@@ -6061,20 +6075,21 @@ impl_writeable_tlv_based!(HTLCPreviousHopData, {
 impl Writeable for ClaimableHTLC {
        fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
                let payment_data = match &self.onion_payload {
-                       OnionPayload::Invoice(data) => Some(data.clone()),
+                       OnionPayload::Invoice { _legacy_hop_data } => Some(_legacy_hop_data),
                        _ => None,
                };
                let keysend_preimage = match self.onion_payload {
-                       OnionPayload::Invoice(_) => None,
+                       OnionPayload::Invoice { .. } => None,
                        OnionPayload::Spontaneous(preimage) => Some(preimage.clone()),
                };
-               write_tlv_fields!
-               (writer,
-                {
-                  (0, self.prev_hop, required), (2, self.value, required),
-                  (4, payment_data, option), (6, self.cltv_expiry, required),
-                        (8, keysend_preimage, option),
-                });
+               write_tlv_fields!(writer, {
+                       (0, self.prev_hop, required),
+                       (1, self.total_msat, required),
+                       (2, self.value, required),
+                       (4, payment_data, option),
+                       (6, self.cltv_expiry, required),
+                       (8, keysend_preimage, option),
+               });
                Ok(())
        }
 }
@@ -6085,32 +6100,41 @@ impl Readable for ClaimableHTLC {
                let mut value = 0;
                let mut payment_data: Option<msgs::FinalOnionHopData> = None;
                let mut cltv_expiry = 0;
+               let mut total_msat = None;
                let mut keysend_preimage: Option<PaymentPreimage> = None;
-               read_tlv_fields!
-               (reader,
-                {
-                  (0, prev_hop, required), (2, value, required),
-                  (4, payment_data, option), (6, cltv_expiry, required),
-                        (8, keysend_preimage, option)
-                });
+               read_tlv_fields!(reader, {
+                       (0, prev_hop, required),
+                       (1, total_msat, option),
+                       (2, value, required),
+                       (4, payment_data, option),
+                       (6, cltv_expiry, required),
+                       (8, keysend_preimage, option)
+               });
                let onion_payload = match keysend_preimage {
                        Some(p) => {
                                if payment_data.is_some() {
                                        return Err(DecodeError::InvalidValue)
                                }
+                               if total_msat.is_none() {
+                                       total_msat = Some(value);
+                               }
                                OnionPayload::Spontaneous(p)
                        },
                        None => {
                                if payment_data.is_none() {
                                        return Err(DecodeError::InvalidValue)
                                }
-                               OnionPayload::Invoice(payment_data.unwrap())
+                               if total_msat.is_none() {
+                                       total_msat = Some(payment_data.as_ref().unwrap().total_msat);
+                               }
+                               OnionPayload::Invoice { _legacy_hop_data: payment_data.unwrap() }
                        },
                };
                Ok(Self {
                        prev_hop: prev_hop.0.unwrap(),
                        timer_ticks: 0,
                        value,
+                       total_msat: total_msat.unwrap(),
                        onion_payload,
                        cltv_expiry,
                })
@@ -7311,7 +7335,7 @@ mod tests {
                // payment verification fails as expected.
                let mut bad_payment_hash = payment_hash.clone();
                bad_payment_hash.0[0] += 1;
-               match inbound_payment::verify(bad_payment_hash, payment_data.clone(), nodes[0].node.highest_seen_timestamp.load(Ordering::Acquire) as u64, &nodes[0].node.inbound_payment_key, &nodes[0].logger) {
+               match inbound_payment::verify(bad_payment_hash, &payment_data, nodes[0].node.highest_seen_timestamp.load(Ordering::Acquire) as u64, &nodes[0].node.inbound_payment_key, &nodes[0].logger) {
                        Ok(_) => panic!("Unexpected ok"),
                        Err(()) => {
                                nodes[0].logger.assert_log_contains("lightning::ln::inbound_payment".to_string(), "Failing HTLC with user-generated payment_hash".to_string(), 1);
@@ -7319,7 +7343,7 @@ mod tests {
                }
 
                // Check that using the original payment hash succeeds.
-               assert!(inbound_payment::verify(payment_hash, payment_data, nodes[0].node.highest_seen_timestamp.load(Ordering::Acquire) as u64, &nodes[0].node.inbound_payment_key, &nodes[0].logger).is_ok());
+               assert!(inbound_payment::verify(payment_hash, &payment_data, nodes[0].node.highest_seen_timestamp.load(Ordering::Acquire) as u64, &nodes[0].node.inbound_payment_key, &nodes[0].logger).is_ok());
        }
 }