Recommend funding_tx to apply anti-fee sniping
[rust-lightning] / lightning / src / ln / channelmanager.rs
index 17a52e29e4a5eecb210fe9d3f10c2edc4306f233..9fd4a24f444bac25c23eac3312cda797faa4590e 100644 (file)
 //! responsible for tracking which channels are open, HTLCs are in flight and reestablishing those
 //! upon reconnect to the relevant peer(s).
 //!
-//! It does not manage routing logic (see routing::router::get_route for that) nor does it manage constructing
+//! It does not manage routing logic (see [`find_route`] for that) nor does it manage constructing
 //! on-chain transactions (it only monitors the chain to watch for any force-closes that might
 //! imply it needs to fail HTLCs/payments/channels it manages).
 //!
+//! [`find_route`]: crate::routing::router::find_route
 
 use bitcoin::blockdata::block::BlockHeader;
 use bitcoin::blockdata::transaction::Transaction;
@@ -1777,12 +1778,14 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                self.list_channels_with_filter(|_| true)
        }
 
-       /// Gets the list of usable channels, in random order. Useful as an argument to
-       /// get_route to ensure non-announced channels are used.
+       /// Gets the list of usable channels, in random order. Useful as an argument to [`find_route`]
+       /// to ensure non-announced channels are used.
        ///
        /// These are guaranteed to have their [`ChannelDetails::is_usable`] value set to true, see the
        /// documentation for [`ChannelDetails::is_usable`] for more info on exactly what the criteria
        /// are.
+       ///
+       /// [`find_route`]: crate::routing::router::find_route
        pub fn list_usable_channels(&self) -> Vec<ChannelDetails> {
                // Note we use is_live here instead of usable which leads to somewhat confused
                // internal/external nomenclature, but that's ok cause that's probably what the user
@@ -2780,6 +2783,9 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
        /// Returns an [`APIError::APIMisuseError`] if the funding_transaction spent non-SegWit outputs
        /// or if no output was found which matches the parameters in [`Event::FundingGenerationReady`].
        ///
+       /// Returns [`APIError::APIMisuseError`] if the funding transaction is not final for propagation
+       /// across the p2p network.
+       ///
        /// Returns [`APIError::ChannelUnavailable`] if a funding transaction has already been provided
        /// for the channel or if the channel has been closed as indicated by [`Event::ChannelClosed`].
        ///
@@ -2795,6 +2801,11 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
        /// not currently support replacing a funding transaction on an existing channel. Instead,
        /// create a new channel with a conflicting funding transaction.
        ///
+       /// Note to keep the miner incentives aligned in moving the blockchain forward, we recommend
+       /// the wallet software generating the funding transaction to apply anti-fee sniping as
+       /// implemented by Bitcoin Core wallet. See <https://bitcoinops.org/en/topics/fee-sniping/>
+       /// for more details.
+       ///
        /// [`Event::FundingGenerationReady`]: crate::util::events::Event::FundingGenerationReady
        /// [`Event::ChannelClosed`]: crate::util::events::Event::ChannelClosed
        pub fn funding_transaction_generated(&self, temporary_channel_id: &[u8; 32], counterparty_node_id: &PublicKey, funding_transaction: Transaction) -> Result<(), APIError> {
@@ -2807,6 +2818,18 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                });
                        }
                }
+               {
+                       let height = self.best_block.read().unwrap().height();
+                       // Transactions are evaluated as final by network mempools at the next block. However, the modules
+                       // constituting our Lightning node might not have perfect sync about their blockchain views. Thus, if
+                       // the wallet module is in advance on the LDK view, allow one more block of headroom.
+                       // TODO: updated if/when https://github.com/rust-bitcoin/rust-bitcoin/pull/994 landed and rust-bitcoin bumped.
+                       if !funding_transaction.input.iter().all(|input| input.sequence == 0xffffffff) && funding_transaction.lock_time < 500_000_000 && funding_transaction.lock_time > height + 2 {
+                               return Err(APIError::APIMisuseError {
+                                       err: "Funding transaction absolute timelock is non-final".to_owned()
+                               });
+                       }
+               }
                self.funding_transaction_generated_intern(temporary_channel_id, counterparty_node_id, funding_transaction, |chan, tx| {
                        let mut output_index = None;
                        let expected_spk = chan.get_funding_redeemscript().to_v0_p2wsh();
@@ -3617,7 +3640,10 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
        // Fail a list of HTLCs that were just freed from the holding cell. The HTLCs need to be
        // failed backwards or, if they were one of our outgoing HTLCs, then their failure needs to
        // be surfaced to the user.
-       fn fail_holding_cell_htlcs(&self, mut htlcs_to_fail: Vec<(HTLCSource, PaymentHash)>, channel_id: [u8; 32]) {
+       fn fail_holding_cell_htlcs(
+               &self, mut htlcs_to_fail: Vec<(HTLCSource, PaymentHash)>, channel_id: [u8; 32],
+               _counterparty_node_id: &PublicKey
+       ) {
                for (htlc_src, payment_hash) in htlcs_to_fail.drain(..) {
                        match htlc_src {
                                HTLCSource::PreviousHopData(HTLCPreviousHopData { .. }) => {
@@ -3765,7 +3791,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                                        .. } => {
                                                // we get a fail_malformed_htlc from the first hop
                                                // TODO: We'd like to generate a NetworkUpdate for temporary
-                                               // failures here, but that would be insufficient as get_route
+                                               // failures here, but that would be insufficient as find_route
                                                // generally ignores its view of our own channels as we provide them via
                                                // ChannelDetails.
                                                // TODO: For non-temporary failures, we really should be closing the
@@ -4211,6 +4237,10 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
        /// [`Event::ChannelClosed::user_channel_id`] to allow tracking of which events correspond
        /// with which `accept_inbound_channel`/`accept_inbound_channel_from_trusted_peer_0conf` call.
        ///
+       /// Note that this method will return an error and reject the channel, if it requires support
+       /// for zero confirmations. Instead, `accept_inbound_channel_from_trusted_peer_0conf` must be
+       /// used to accept such channels.
+       ///
        /// [`Event::OpenChannelRequest`]: events::Event::OpenChannelRequest
        /// [`Event::ChannelClosed::user_channel_id`]: events::Event::ChannelClosed::user_channel_id
        pub fn accept_inbound_channel(&self, temporary_channel_id: &[u8; 32], counterparty_node_id: &PublicKey, user_channel_id: u64) -> Result<(), APIError> {
@@ -4252,7 +4282,20 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                if *counterparty_node_id != channel.get().get_counterparty_node_id() {
                                        return Err(APIError::APIMisuseError { err: "The passed counterparty_node_id doesn't match the channel's counterparty node_id".to_owned() });
                                }
-                               if accept_0conf { channel.get_mut().set_0conf(); }
+                               if accept_0conf {
+                                       channel.get_mut().set_0conf();
+                               } else if channel.get().get_channel_type().requires_zero_conf() {
+                                       let send_msg_err_event = events::MessageSendEvent::HandleError {
+                                               node_id: channel.get().get_counterparty_node_id(),
+                                               action: msgs::ErrorAction::SendErrorMessage{
+                                                       msg: msgs::ErrorMessage { channel_id: temporary_channel_id.clone(), data: "No zero confirmation channels accepted".to_owned(), }
+                                               }
+                                       };
+                                       channel_state.pending_msg_events.push(send_msg_err_event);
+                                       let _ = remove_channel!(self, channel_state, channel);
+                                       return Err(APIError::APIMisuseError { err: "Please use accept_inbound_channel_from_trusted_peer_0conf to accept channels with zero confirmations.".to_owned() });
+                               }
+
                                channel_state.pending_msg_events.push(events::MessageSendEvent::SendAcceptChannel {
                                        node_id: channel.get().get_counterparty_node_id(),
                                        msg: channel.get_mut().accept_inbound_channel(user_channel_id),
@@ -4294,6 +4337,9 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                        },
                        hash_map::Entry::Vacant(entry) => {
                                if !self.default_configuration.manually_accept_inbound_channels {
+                                       if channel.get_channel_type().requires_zero_conf() {
+                                               return Err(MsgHandleErrInternal::send_err_msg_no_close("No zero confirmation channels accepted".to_owned(), msg.temporary_channel_id.clone()));
+                                       }
                                        channel_state.pending_msg_events.push(events::MessageSendEvent::SendAcceptChannel {
                                                node_id: counterparty_node_id.clone(),
                                                msg: channel.accept_inbound_channel(0),
@@ -4805,7 +4851,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                hash_map::Entry::Vacant(_) => break Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
                        }
                };
-               self.fail_holding_cell_htlcs(htlcs_to_fail, msg.channel_id);
+               self.fail_holding_cell_htlcs(htlcs_to_fail, msg.channel_id, counterparty_node_id);
                match res {
                        Ok((pending_forwards, mut pending_failures, finalized_claim_htlcs,
                                short_channel_id, channel_outpoint)) =>
@@ -4945,7 +4991,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                        }
                };
                post_handle_chan_restoration!(self, chan_restoration_res);
-               self.fail_holding_cell_htlcs(htlcs_failed_forward, msg.channel_id);
+               self.fail_holding_cell_htlcs(htlcs_failed_forward, msg.channel_id, counterparty_node_id);
 
                if let Some(channel_ready_msg) = need_lnd_workaround {
                        self.internal_channel_ready(counterparty_node_id, &channel_ready_msg)?;
@@ -5043,7 +5089,11 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                match chan.maybe_free_holding_cell_htlcs(&self.logger) {
                                        Ok((commitment_opt, holding_cell_failed_htlcs)) => {
                                                if !holding_cell_failed_htlcs.is_empty() {
-                                                       failed_htlcs.push((holding_cell_failed_htlcs, *channel_id));
+                                                       failed_htlcs.push((
+                                                               holding_cell_failed_htlcs,
+                                                               *channel_id,
+                                                               chan.get_counterparty_node_id()
+                                                       ));
                                                }
                                                if let Some((commitment_update, monitor_update)) = commitment_opt {
                                                        if let Err(e) = self.chain_monitor.update_channel(chan.get_funding_txo().unwrap(), monitor_update) {
@@ -5071,8 +5121,8 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                }
 
                let has_update = has_monitor_update || !failed_htlcs.is_empty() || !handle_errors.is_empty();
-               for (failures, channel_id) in failed_htlcs.drain(..) {
-                       self.fail_holding_cell_htlcs(failures, channel_id);
+               for (failures, channel_id, counterparty_node_id) in failed_htlcs.drain(..) {
+                       self.fail_holding_cell_htlcs(failures, channel_id, &counterparty_node_id);
                }
 
                for (counterparty_node_id, err) in handle_errors.drain(..) {
@@ -7335,8 +7385,8 @@ mod tests {
                        final_cltv_expiry_delta: TEST_FINAL_CLTV,
                };
                let route = find_route(
-                       &nodes[0].node.get_our_node_id(), &route_params, nodes[0].network_graph, None,
-                       nodes[0].logger, &scorer, &random_seed_bytes
+                       &nodes[0].node.get_our_node_id(), &route_params, &nodes[0].network_graph.read_only(),
+                       None, nodes[0].logger, &scorer, &random_seed_bytes
                ).unwrap();
                nodes[0].node.send_spontaneous_payment(&route, Some(payment_preimage)).unwrap();
                check_added_monitors!(nodes[0], 1);
@@ -7366,8 +7416,8 @@ mod tests {
                // To start (2), send a keysend payment but don't claim it.
                let payment_preimage = PaymentPreimage([42; 32]);
                let route = find_route(
-                       &nodes[0].node.get_our_node_id(), &route_params, nodes[0].network_graph, None,
-                       nodes[0].logger, &scorer, &random_seed_bytes
+                       &nodes[0].node.get_our_node_id(), &route_params, &nodes[0].network_graph.read_only(),
+                       None, nodes[0].logger, &scorer, &random_seed_bytes
                ).unwrap();
                let (payment_hash, _) = nodes[0].node.send_spontaneous_payment(&route, Some(payment_preimage)).unwrap();
                check_added_monitors!(nodes[0], 1);
@@ -7430,8 +7480,9 @@ mod tests {
                let scorer = test_utils::TestScorer::with_penalty(0);
                let random_seed_bytes = chanmon_cfgs[1].keys_manager.get_secure_random_bytes();
                let route = find_route(
-                       &payer_pubkey, &route_params, network_graph, Some(&first_hops.iter().collect::<Vec<_>>()),
-                       nodes[0].logger, &scorer, &random_seed_bytes
+                       &payer_pubkey, &route_params, &network_graph.read_only(),
+                       Some(&first_hops.iter().collect::<Vec<_>>()), nodes[0].logger, &scorer,
+                       &random_seed_bytes
                ).unwrap();
 
                let test_preimage = PaymentPreimage([42; 32]);
@@ -7474,8 +7525,9 @@ mod tests {
                let scorer = test_utils::TestScorer::with_penalty(0);
                let random_seed_bytes = chanmon_cfgs[1].keys_manager.get_secure_random_bytes();
                let route = find_route(
-                       &payer_pubkey, &route_params, network_graph, Some(&first_hops.iter().collect::<Vec<_>>()),
-                       nodes[0].logger, &scorer, &random_seed_bytes
+                       &payer_pubkey, &route_params, &network_graph.read_only(),
+                       Some(&first_hops.iter().collect::<Vec<_>>()), nodes[0].logger, &scorer,
+                       &random_seed_bytes
                ).unwrap();
 
                let test_preimage = PaymentPreimage([42; 32]);
@@ -7564,7 +7616,7 @@ pub mod bench {
        use ln::features::{InitFeatures, InvoiceFeatures};
        use ln::functional_test_utils::*;
        use ln::msgs::{ChannelMessageHandler, Init};
-       use routing::network_graph::NetworkGraph;
+       use routing::gossip::NetworkGraph;
        use routing::router::{PaymentParameters, get_route};
        use util::test_utils;
        use util::config::UserConfig;
@@ -7667,7 +7719,7 @@ pub mod bench {
                        _ => panic!(),
                }
 
-               let dummy_graph = NetworkGraph::new(genesis_hash);
+               let dummy_graph = NetworkGraph::new(genesis_hash, &logger_a);
 
                let mut payment_count: u64 = 0;
                macro_rules! send_payment {