Make Channel non-public except in fuzztarget mode, bump version
[rust-lightning] / src / ln / channelmanager.rs
index 2f13b80452f59c167b5c3b7c33733de5ebe49273..ff78a27df58b3243979758af8ba8889e36b63e01 100644 (file)
@@ -11,7 +11,7 @@ use secp256k1::{Secp256k1,Message};
 use secp256k1::ecdh::SharedSecret;
 use secp256k1;
 
-use chain::chaininterface::{ChainListener,ChainWatchInterface,FeeEstimator};
+use chain::chaininterface::{BroadcasterInterface,ChainListener,ChainWatchInterface,FeeEstimator};
 use ln::channel::Channel;
 use ln::channelmonitor::ManyChannelMonitor;
 use ln::router::Route;
@@ -41,8 +41,8 @@ pub struct PendingForwardHTLCInfo {
        amt_to_forward: u64,
        outgoing_cltv_value: u32,
 }
-//TODO: This is public, and needed to call Channel::update_add_htlc, so there needs to be a way to
-//initialize it usefully...probably make it optional in Channel instead).
+
+#[cfg(feature = "fuzztarget")]
 impl PendingForwardHTLCInfo {
        pub fn dummy() -> Self {
                Self {
@@ -126,6 +126,7 @@ pub struct ChannelManager {
        fee_estimator: Arc<FeeEstimator>,
        monitor: Arc<ManyChannelMonitor>,
        chain_monitor: Arc<ChainWatchInterface>,
+       tx_broadcaster: Arc<BroadcasterInterface>,
 
        announce_channels_publicly: bool,
        fee_proportional_millionths: u32,
@@ -159,24 +160,40 @@ struct OnionKeys {
        mu: [u8; 32],
 }
 
+pub struct ChannelDetails {
+       /// The channel's ID (prior to funding transaction generation, this is a random 32 bytes,
+       /// thereafter this is the txid of the funding transaction xor the funding transaction output).
+       /// Note that this means this value is *not* persistent - it can change once during the
+       /// lifetime of the channel.
+       pub channel_id: Uint256,
+       /// The position of the funding transaction in the chain. None if the funding transaction has
+       /// not yet been confirmed and the channel fully opened.
+       pub short_channel_id: Option<u64>,
+       pub remote_network_id: PublicKey,
+       pub channel_value_satoshis: u64,
+       /// The user_id passed in to create_channel, or 0 if the channel was inbound.
+       pub user_id: u64,
+}
+
 impl ChannelManager {
        /// Constructs a new ChannelManager to hold several channels and route between them. This is
        /// the main "logic hub" for all channel-related actions, and implements ChannelMessageHandler.
        /// fee_proportional_millionths is an optional fee to charge any payments routed through us.
        /// Non-proportional fees are fixed according to our risk using the provided fee estimator.
        /// panics if channel_value_satoshis is >= (1 << 24)!
-       pub fn new(our_network_key: SecretKey, fee_proportional_millionths: u32, announce_channels_publicly: bool, network: Network, feeest: Arc<FeeEstimator>, monitor: Arc<ManyChannelMonitor>, chain_monitor: Arc<ChainWatchInterface>) -> Result<Arc<ChannelManager>, secp256k1::Error> {
+       pub fn new(our_network_key: SecretKey, fee_proportional_millionths: u32, announce_channels_publicly: bool, network: Network, feeest: Arc<FeeEstimator>, monitor: Arc<ManyChannelMonitor>, chain_monitor: Arc<ChainWatchInterface>, tx_broadcaster: Arc<BroadcasterInterface>) -> Result<Arc<ChannelManager>, secp256k1::Error> {
                let secp_ctx = Secp256k1::new();
 
                let res = Arc::new(ChannelManager {
                        genesis_hash: genesis_block(network).header.bitcoin_hash(),
                        fee_estimator: feeest.clone(),
                        monitor: monitor.clone(),
-                       chain_monitor: chain_monitor,
+                       chain_monitor,
+                       tx_broadcaster,
 
-                       announce_channels_publicly: announce_channels_publicly,
-                       fee_proportional_millionths: fee_proportional_millionths,
-                       secp_ctx: secp_ctx,
+                       announce_channels_publicly,
+                       fee_proportional_millionths,
+                       secp_ctx,
 
                        channel_state: Mutex::new(ChannelHolder{
                                by_id: HashMap::new(),
@@ -185,7 +202,7 @@ impl ChannelManager {
                                forward_htlcs: HashMap::new(),
                                claimable_htlcs: HashMap::new(),
                        }),
-                       our_network_key: our_network_key,
+                       our_network_key,
 
                        pending_events: Mutex::new(Vec::new()),
                });
@@ -204,6 +221,47 @@ impl ChannelManager {
                }
        }
 
+       /// Gets the list of open channels, in random order. See ChannelDetail field documentation for
+       /// more information.
+       pub fn list_channels(&self) -> Vec<ChannelDetails> {
+               let channel_state = self.channel_state.lock().unwrap();
+               let mut res = Vec::with_capacity(channel_state.by_id.len());
+               for (channel_id, channel) in channel_state.by_id.iter() {
+                       res.push(ChannelDetails {
+                               channel_id: (*channel_id).clone(),
+                               short_channel_id: channel.get_short_channel_id(),
+                               remote_network_id: channel.get_their_node_id(),
+                               channel_value_satoshis: channel.get_value_satoshis(),
+                               user_id: channel.get_user_id(),
+                       });
+               }
+               res
+       }
+
+       /// Begins the process of closing a channel. After this call (plus some timeout), no new HTLCs
+       /// will be accepted on the given channel, and after additional timeout/the closing of all
+       /// pending HTLCs, the channel will be closed on chain.
+       pub fn close_channel(&self, channel_id: &Uint256) -> Result<msgs::Shutdown, HandleError> {
+               let res = {
+                       let mut channel_state = self.channel_state.lock().unwrap();
+                       match channel_state.by_id.entry(channel_id.clone()) {
+                               hash_map::Entry::Occupied(mut chan_entry) => {
+                                       let res = chan_entry.get_mut().get_shutdown()?;
+                                       if chan_entry.get().is_shutdown() {
+                                               chan_entry.remove_entry();
+                                       }
+                                       res
+                               },
+                               hash_map::Entry::Vacant(_) => return Err(HandleError{err: "No such channel", msg: None})
+                       }
+               };
+               for payment_hash in res.1 {
+                       // unknown_next_peer...I dunno who that is anymore....
+                       self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), &payment_hash, HTLCFailReason::Reason { failure_code: 0x4000 | 10, data: &[0; 0] });
+               }
+               Ok(res.0)
+       }
+
        #[inline]
        fn gen_rho_mu_from_shared_secret(shared_secret: &SharedSecret) -> ([u8; 32], [u8; 32]) {
                ({
@@ -577,7 +635,7 @@ impl ChannelManager {
                        let mut channel_state_lock = self.channel_state.lock().unwrap();
                        let channel_state = channel_state_lock.borrow_parts();
 
-                       if Instant::now() < *channel_state.next_forward {
+                       if cfg!(not(feature = "fuzztarget")) && Instant::now() < *channel_state.next_forward {
                                return;
                        }
 
@@ -772,6 +830,7 @@ impl ChannelManager {
                                if from_user {
                                        panic!("Called claim_funds with a preimage for an outgoing payment. There is nothing we can do with this, and something is seriously wrong if you knew this...");
                                }
+                               mem::drop(channel_state);
                                let mut pending_events = self.pending_events.lock().unwrap();
                                pending_events.push(events::Event::PaymentSent {
                                        payment_preimage
@@ -795,6 +854,7 @@ impl ChannelManager {
                                        }
                                };
 
+                               mem::drop(channel_state);
                                let mut pending_events = self.pending_events.lock().unwrap();
                                pending_events.push(events::Event::SendFulfillHTLC {
                                        node_id: node_id,
@@ -976,12 +1036,57 @@ impl ChannelMessageHandler for ChannelManager {
                };
        }
 
-       fn handle_shutdown(&self, _their_node_id: &PublicKey, _msg: &msgs::Shutdown) -> Result<(), HandleError> {
-               unimplemented!()
+       fn handle_shutdown(&self, their_node_id: &PublicKey, msg: &msgs::Shutdown) -> Result<(Option<msgs::Shutdown>, Option<msgs::ClosingSigned>), HandleError> {
+               let res = {
+                       let mut channel_state = self.channel_state.lock().unwrap();
+
+                       match channel_state.by_id.entry(msg.channel_id.clone()) {
+                               hash_map::Entry::Occupied(mut chan_entry) => {
+                                       if chan_entry.get().get_their_node_id() != *their_node_id {
+                                               return Err(HandleError{err: "Got a message for a channel from the wrong node!", msg: None})
+                                       }
+                                       let res = chan_entry.get_mut().shutdown(&*self.fee_estimator, &msg)?;
+                                       if chan_entry.get().is_shutdown() {
+                                               chan_entry.remove_entry();
+                                       }
+                                       res
+                               },
+                               hash_map::Entry::Vacant(_) => return Err(HandleError{err: "Failed to find corresponding channel", msg: None})
+                       }
+               };
+               for payment_hash in res.2 {
+                       // unknown_next_peer...I dunno who that is anymore....
+                       self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), &payment_hash, HTLCFailReason::Reason { failure_code: 0x4000 | 10, data: &[0; 0] });
+               }
+               Ok((res.0, res.1))
        }
 
-       fn handle_closing_signed(&self, _their_node_id: &PublicKey, _msg: &msgs::ClosingSigned) -> Result<(), HandleError> {
-               unimplemented!()
+       fn handle_closing_signed(&self, their_node_id: &PublicKey, msg: &msgs::ClosingSigned) -> Result<Option<msgs::ClosingSigned>, HandleError> {
+               let res = {
+                       let mut channel_state = self.channel_state.lock().unwrap();
+                       match channel_state.by_id.entry(msg.channel_id.clone()) {
+                               hash_map::Entry::Occupied(mut chan_entry) => {
+                                       if chan_entry.get().get_their_node_id() != *their_node_id {
+                                               return Err(HandleError{err: "Got a message for a channel from the wrong node!", msg: None})
+                                       }
+                                       let res = chan_entry.get_mut().closing_signed(&*self.fee_estimator, &msg)?;
+                                       if res.1.is_some() {
+                                               // We're done with this channel, we've got a signed closing transaction and
+                                               // will send the closing_signed back to the remote peer upon return. This
+                                               // also implies there are no pending HTLCs left on the channel, so we can
+                                               // fully delete it from tracking (the channel monitor is still around to
+                                               // watch for old state broadcasts)!
+                                               chan_entry.remove_entry();
+                                       }
+                                       res
+                               },
+                               hash_map::Entry::Vacant(_) => return Err(HandleError{err: "Failed to find corresponding channel", msg: None})
+                       }
+               };
+               if let Some(broadcast_tx) = res.1 {
+                       self.tx_broadcaster.broadcast_transaction(&broadcast_tx);
+               }
+               Ok(res.0)
        }
 
        fn handle_update_add_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateAddHTLC) -> Result<(), msgs::HandleError> {
@@ -1212,54 +1317,52 @@ impl ChannelMessageHandler for ChannelManager {
                Ok(res)
        }
 
-       fn handle_update_fulfill_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFulfillHTLC) -> Result<Option<(Vec<msgs::UpdateAddHTLC>, msgs::CommitmentSigned)>, HandleError> {
-               let res = {
+       fn handle_update_fulfill_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFulfillHTLC) -> Result<(), HandleError> {
+               {
                        let mut channel_state = self.channel_state.lock().unwrap();
                        match channel_state.by_id.get_mut(&msg.channel_id) {
                                Some(chan) => {
                                        if chan.get_their_node_id() != *their_node_id {
                                                return Err(HandleError{err: "Got a message for a channel from the wrong node!", msg: None})
                                        }
-                                       chan.update_fulfill_htlc(&msg)
+                                       chan.update_fulfill_htlc(&msg)?;
                                },
                                None => return Err(HandleError{err: "Failed to find corresponding channel", msg: None})
                        }
-               };
+               }
                //TODO: Delay the claimed_funds relaying just like we do outbound relay!
                self.claim_funds_internal(msg.payment_preimage.clone(), false);
-               res
+               Ok(())
        }
 
-       fn handle_update_fail_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailHTLC) -> Result<Option<(Vec<msgs::UpdateAddHTLC>, msgs::CommitmentSigned)>, HandleError> {
+       fn handle_update_fail_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailHTLC) -> Result<(), HandleError> {
                let mut channel_state = self.channel_state.lock().unwrap();
-               let res;
-               match channel_state.by_id.get_mut(&msg.channel_id) {
+               let payment_hash = match channel_state.by_id.get_mut(&msg.channel_id) {
                        Some(chan) => {
                                if chan.get_their_node_id() != *their_node_id {
                                        return Err(HandleError{err: "Got a message for a channel from the wrong node!", msg: None})
                                }
-                               res = chan.update_fail_htlc(&msg)?;
+                               chan.update_fail_htlc(&msg)?
                        },
                        None => return Err(HandleError{err: "Failed to find corresponding channel", msg: None})
-               }
-               self.fail_htlc_backwards_internal(channel_state, &res.0, HTLCFailReason::ErrorPacket { err: &msg.reason });
-               Ok(res.1)
+               };
+               self.fail_htlc_backwards_internal(channel_state, &payment_hash, HTLCFailReason::ErrorPacket { err: &msg.reason });
+               Ok(())
        }
 
-       fn handle_update_fail_malformed_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailMalformedHTLC) -> Result<Option<(Vec<msgs::UpdateAddHTLC>, msgs::CommitmentSigned)>, HandleError> {
+       fn handle_update_fail_malformed_htlc(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFailMalformedHTLC) -> Result<(), HandleError> {
                let mut channel_state = self.channel_state.lock().unwrap();
-               let res;
-               match channel_state.by_id.get_mut(&msg.channel_id) {
+               let payment_hash = match channel_state.by_id.get_mut(&msg.channel_id) {
                        Some(chan) => {
                                if chan.get_their_node_id() != *their_node_id {
                                        return Err(HandleError{err: "Got a message for a channel from the wrong node!", msg: None})
                                }
-                               res = chan.update_fail_malformed_htlc(&msg)?;
+                               chan.update_fail_malformed_htlc(&msg)?
                        },
                        None => return Err(HandleError{err: "Failed to find corresponding channel", msg: None})
-               }
-               self.fail_htlc_backwards_internal(channel_state, &res.0, HTLCFailReason::Reason { failure_code: msg.failure_code, data: &[0;0] });
-               Ok(res.1)
+               };
+               self.fail_htlc_backwards_internal(channel_state, &payment_hash, HTLCFailReason::Reason { failure_code: msg.failure_code, data: &[0;0] });
+               Ok(())
        }
 
        fn handle_commitment_signed(&self, their_node_id: &PublicKey, msg: &msgs::CommitmentSigned) -> Result<msgs::RevokeAndACK, HandleError> {
@@ -1310,22 +1413,21 @@ impl ChannelMessageHandler for ChannelManager {
                Ok(res)
        }
 
-       fn handle_revoke_and_ack(&self, their_node_id: &PublicKey, msg: &msgs::RevokeAndACK) -> Result<(), HandleError> {
-               let monitor = {
+       fn handle_revoke_and_ack(&self, their_node_id: &PublicKey, msg: &msgs::RevokeAndACK) -> Result<Option<(Vec<msgs::UpdateAddHTLC>, msgs::CommitmentSigned)>, HandleError> {
+               let (res, monitor) = {
                        let mut channel_state = self.channel_state.lock().unwrap();
                        match channel_state.by_id.get_mut(&msg.channel_id) {
                                Some(chan) => {
                                        if chan.get_their_node_id() != *their_node_id {
                                                return Err(HandleError{err: "Got a message for a channel from the wrong node!", msg: None})
                                        }
-                                       chan.revoke_and_ack(&msg)?;
-                                       chan.channel_monitor()
+                                       (chan.revoke_and_ack(&msg)?, chan.channel_monitor())
                                },
                                None => return Err(HandleError{err: "Failed to find corresponding channel", msg: None})
                        }
                };
                self.monitor.add_update_monitor(monitor.get_funding_txo().unwrap(), monitor)?;
-               Ok(())
+               Ok(res)
        }
 
        fn handle_update_fee(&self, their_node_id: &PublicKey, msg: &msgs::UpdateFee) -> Result<(), HandleError> {
@@ -1392,6 +1494,7 @@ mod tests {
 
        use bitcoin::util::misc::hex_bytes;
        use bitcoin::util::hash::Sha256dHash;
+       use bitcoin::util::uint::Uint256;
        use bitcoin::blockdata::block::BlockHeader;
        use bitcoin::blockdata::transaction::Transaction;
        use bitcoin::network::constants::Network;
@@ -1406,7 +1509,7 @@ mod tests {
 
        use rand::{thread_rng,Rng};
 
-       use std::sync::Arc;
+       use std::sync::{Arc, Mutex};
        use std::default::Default;
        use std::time::Instant;
 
@@ -1571,20 +1674,20 @@ mod tests {
                }
        }
 
-       fn create_chan_between_nodes(node_a: &ChannelManager, chain_a: &chaininterface::ChainWatchInterfaceUtil, node_b: &ChannelManager, chain_b: &chaininterface::ChainWatchInterfaceUtil) -> (msgs::ChannelAnnouncement, msgs::ChannelUpdate, msgs::ChannelUpdate) {
-               let open_chan = node_a.create_channel(node_b.get_our_node_id(), (1 << 24) - 1, 42).unwrap();
+       fn create_chan_between_nodes(node_a: &ChannelManager, chain_a: &chaininterface::ChainWatchInterfaceUtil, node_b: &ChannelManager, chain_b: &chaininterface::ChainWatchInterfaceUtil) -> (msgs::ChannelAnnouncement, msgs::ChannelUpdate, msgs::ChannelUpdate, Uint256) {
+               let open_chan = node_a.create_channel(node_b.get_our_node_id(), 100000, 42).unwrap();
                let accept_chan = node_b.handle_open_channel(&node_a.get_our_node_id(), &open_chan).unwrap();
                node_a.handle_accept_channel(&node_b.get_our_node_id(), &accept_chan).unwrap();
 
                let chan_id = unsafe { CHAN_COUNT };
-               let tx = Transaction { version: chan_id as u32, lock_time: 0, input: Vec::new(), output: Vec::new(), witness: Vec::new() };
+               let tx = Transaction { version: chan_id as u32, lock_time: 0, input: Vec::new(), output: Vec::new() };
                let funding_output = (Sha256dHash::from_data(&serialize(&tx).unwrap()[..]), chan_id);
 
                let events_1 = node_a.get_and_clear_pending_events();
                assert_eq!(events_1.len(), 1);
                match events_1[0] {
                        Event::FundingGenerationReady { ref temporary_channel_id, ref channel_value_satoshis, output_script: _, user_channel_id } => {
-                               assert_eq!(*channel_value_satoshis, (1 << 24) - 1);
+                               assert_eq!(*channel_value_satoshis, 100000);
                                assert_eq!(user_channel_id, 42);
 
                                node_a.funding_transaction_generated(&temporary_channel_id, funding_output.clone());
@@ -1628,12 +1731,15 @@ mod tests {
                        _ => panic!("Unexpected event"),
                };
 
+               let channel_id;
+
                confirm_transaction(&chain_b, &tx);
                let events_5 = node_b.get_and_clear_pending_events();
                assert_eq!(events_5.len(), 1);
                let as_announcement_sigs = match events_5[0] {
                        Event::SendFundingLocked { ref node_id, ref msg, ref announcement_sigs } => {
                                assert_eq!(*node_id, node_a.get_our_node_id());
+                               channel_id = msg.channel_id.clone();
                                let as_announcement_sigs = node_a.handle_funding_locked(&node_b.get_our_node_id(), msg).unwrap().unwrap();
                                node_a.handle_announcement_signatures(&node_b.get_our_node_id(), &(*announcement_sigs).clone().unwrap()).unwrap();
                                as_announcement_sigs
@@ -1665,7 +1771,42 @@ mod tests {
                        CHAN_COUNT += 1;
                }
 
-               ((*announcement).clone(), (*as_update).clone(), (*bs_update).clone())
+               ((*announcement).clone(), (*as_update).clone(), (*bs_update).clone(), channel_id)
+       }
+
+       fn close_channel(outbound_node: &ChannelManager, outbound_broadcaster: &test_utils::TestBroadcaster, inbound_node: &ChannelManager, inbound_broadcaster: &test_utils::TestBroadcaster, channel_id: &Uint256, close_inbound_first: bool) {
+               let (node_a, broadcaster_a) = if close_inbound_first { (inbound_node, inbound_broadcaster) } else { (outbound_node, outbound_broadcaster) };
+               let (node_b, broadcaster_b) = if close_inbound_first { (outbound_node, outbound_broadcaster) } else { (inbound_node, inbound_broadcaster) };
+               let (tx_a, tx_b);
+
+               let shutdown_a = node_a.close_channel(channel_id).unwrap();
+               let (shutdown_b, mut closing_signed_b) = node_b.handle_shutdown(&node_a.get_our_node_id(), &shutdown_a).unwrap();
+               if !close_inbound_first {
+                       assert!(closing_signed_b.is_none());
+               }
+               let (empty_a, mut closing_signed_a) = node_a.handle_shutdown(&node_b.get_our_node_id(), &shutdown_b.unwrap()).unwrap();
+               assert!(empty_a.is_none());
+               if close_inbound_first {
+                       assert!(closing_signed_a.is_none());
+                       closing_signed_a = node_a.handle_closing_signed(&node_b.get_our_node_id(), &closing_signed_b.unwrap()).unwrap();
+                       assert_eq!(broadcaster_a.txn_broadcasted.lock().unwrap().len(), 1);
+                       tx_a = broadcaster_a.txn_broadcasted.lock().unwrap().remove(0);
+
+                       let empty_b = node_b.handle_closing_signed(&node_a.get_our_node_id(), &closing_signed_a.unwrap()).unwrap();
+                       assert!(empty_b.is_none());
+                       assert_eq!(broadcaster_b.txn_broadcasted.lock().unwrap().len(), 1);
+                       tx_b = broadcaster_b.txn_broadcasted.lock().unwrap().remove(0);
+               } else {
+                       closing_signed_b = node_b.handle_closing_signed(&node_a.get_our_node_id(), &closing_signed_a.unwrap()).unwrap();
+                       assert_eq!(broadcaster_b.txn_broadcasted.lock().unwrap().len(), 1);
+                       tx_b = broadcaster_b.txn_broadcasted.lock().unwrap().remove(0);
+
+                       let empty_a2 = node_a.handle_closing_signed(&node_b.get_our_node_id(), &closing_signed_b.unwrap()).unwrap();
+                       assert!(empty_a2.is_none());
+                       assert_eq!(broadcaster_a.txn_broadcasted.lock().unwrap().len(), 1);
+                       tx_a = broadcaster_a.txn_broadcasted.lock().unwrap().remove(0);
+               }
+               assert_eq!(tx_a, tx_b);
        }
 
        struct SendEvent {
@@ -1676,7 +1817,7 @@ mod tests {
        impl SendEvent {
                fn from_event(event: Event) -> SendEvent {
                        match event {
-                               Event::SendHTLCs{ node_id, msgs, commitment_msg } => {
+                               Event::SendHTLCs { node_id, msgs, commitment_msg } => {
                                        SendEvent { node_id: node_id, msgs: msgs, commitment_msg: commitment_msg }
                                },
                                _ => panic!("Unexpected event type!"),
@@ -1711,7 +1852,7 @@ mod tests {
 
                        node.handle_update_add_htlc(&prev_node.get_our_node_id(), &payment_event.msgs[0]).unwrap();
                        let revoke_and_ack = node.handle_commitment_signed(&prev_node.get_our_node_id(), &payment_event.commitment_msg).unwrap();
-                       prev_node.handle_revoke_and_ack(&node.get_our_node_id(), &revoke_and_ack).unwrap();
+                       assert!(prev_node.handle_revoke_and_ack(&node.get_our_node_id(), &revoke_and_ack).unwrap().is_none());
 
                        let events_1 = node.get_and_clear_pending_events();
                        assert_eq!(events_1.len(), 1);
@@ -1746,15 +1887,7 @@ mod tests {
                (our_payment_preimage, our_payment_hash)
        }
 
-       fn send_payment(origin_node: &ChannelManager, origin_router: &Router, expected_route: &[&ChannelManager], recv_value: u64) {
-               let route = origin_router.get_route(&expected_route.last().unwrap().get_our_node_id(), &Vec::new(), recv_value, 142).unwrap();
-               assert_eq!(route.hops.len(), expected_route.len());
-               for (node, hop) in expected_route.iter().zip(route.hops.iter()) {
-                       assert_eq!(hop.pubkey, node.get_our_node_id());
-               }
-
-               let our_payment_preimage = send_along_route(origin_node, route, expected_route, recv_value).0;
-
+       fn claim_payment(origin_node: &ChannelManager, expected_route: &[&ChannelManager], our_payment_preimage: [u8; 32]) {
                assert!(expected_route.last().unwrap().claim_funds(our_payment_preimage));
 
                let mut expected_next_node = expected_route.last().unwrap().get_our_node_id();
@@ -1764,7 +1897,7 @@ mod tests {
                        assert_eq!(expected_next_node, node.get_our_node_id());
                        match next_msg {
                                Some(msg) => {
-                                       assert!(node.handle_update_fulfill_htlc(&prev_node.get_our_node_id(), &msg).unwrap().is_none());
+                                       node.handle_update_fulfill_htlc(&prev_node.get_our_node_id(), &msg).unwrap();
                                }, None => {}
                        }
 
@@ -1782,7 +1915,7 @@ mod tests {
                }
 
                assert_eq!(expected_next_node, origin_node.get_our_node_id());
-               assert!(origin_node.handle_update_fulfill_htlc(&expected_route.first().unwrap().get_our_node_id(), &next_msg.unwrap()).unwrap().is_none());
+               origin_node.handle_update_fulfill_htlc(&expected_route.first().unwrap().get_our_node_id(), &next_msg.unwrap()).unwrap();
 
                let events = origin_node.get_and_clear_pending_events();
                assert_eq!(events.len(), 1);
@@ -1794,6 +1927,42 @@ mod tests {
                }
        }
 
+       fn route_payment(origin_node: &ChannelManager, origin_router: &Router, expected_route: &[&ChannelManager], recv_value: u64) -> ([u8; 32], [u8; 32]) {
+               let route = origin_router.get_route(&expected_route.last().unwrap().get_our_node_id(), &Vec::new(), recv_value, 142).unwrap();
+               assert_eq!(route.hops.len(), expected_route.len());
+               for (node, hop) in expected_route.iter().zip(route.hops.iter()) {
+                       assert_eq!(hop.pubkey, node.get_our_node_id());
+               }
+
+               send_along_route(origin_node, route, expected_route, recv_value)
+       }
+
+       fn route_over_limit(origin_node: &ChannelManager, origin_router: &Router, expected_route: &[&ChannelManager], recv_value: u64) {
+               let route = origin_router.get_route(&expected_route.last().unwrap().get_our_node_id(), &Vec::new(), recv_value, 142).unwrap();
+               assert_eq!(route.hops.len(), expected_route.len());
+               for (node, hop) in expected_route.iter().zip(route.hops.iter()) {
+                       assert_eq!(hop.pubkey, node.get_our_node_id());
+               }
+
+               let our_payment_preimage = unsafe { [PAYMENT_COUNT; 32] };
+               unsafe { PAYMENT_COUNT += 1 };
+               let our_payment_hash = {
+                       let mut sha = Sha256::new();
+                       sha.input(&our_payment_preimage[..]);
+                       let mut ret = [0; 32];
+                       sha.result(&mut ret);
+                       ret
+               };
+
+               let err = origin_node.send_payment(route, our_payment_hash).err().unwrap();
+               assert_eq!(err.err, "Cannot send value that would put us over our max HTLC value in flight");
+       }
+
+       fn send_payment(origin_node: &ChannelManager, origin_router: &Router, expected_route: &[&ChannelManager], recv_value: u64) {
+               let our_payment_preimage = route_payment(origin_node, origin_router, expected_route, recv_value).0;
+               claim_payment(origin_node, expected_route, our_payment_preimage);
+       }
+
        fn send_failed_payment(origin_node: &ChannelManager, origin_router: &Router, expected_route: &[&ChannelManager]) {
                let route = origin_router.get_route(&expected_route.last().unwrap().get_our_node_id(), &Vec::new(), 1000000, 142).unwrap();
                assert_eq!(route.hops.len(), expected_route.len());
@@ -1811,7 +1980,7 @@ mod tests {
                        assert_eq!(expected_next_node, node.get_our_node_id());
                        match next_msg {
                                Some(msg) => {
-                                       assert!(node.handle_update_fail_htlc(&prev_node.get_our_node_id(), &msg).unwrap().is_none());
+                                       node.handle_update_fail_htlc(&prev_node.get_our_node_id(), &msg).unwrap();
                                }, None => {}
                        }
 
@@ -1829,7 +1998,7 @@ mod tests {
                }
 
                assert_eq!(expected_next_node, origin_node.get_our_node_id());
-               assert!(origin_node.handle_update_fail_htlc(&expected_route.first().unwrap().get_our_node_id(), &next_msg.unwrap()).unwrap().is_none());
+               origin_node.handle_update_fail_htlc(&expected_route.first().unwrap().get_our_node_id(), &next_msg.unwrap()).unwrap();
 
                let events = origin_node.get_and_clear_pending_events();
                assert_eq!(events.len(), 1);
@@ -1851,45 +2020,49 @@ mod tests {
                let feeest_1 = Arc::new(test_utils::TestFeeEstimator { sat_per_vbyte: 1 });
                let chain_monitor_1 = Arc::new(chaininterface::ChainWatchInterfaceUtil::new());
                let chan_monitor_1 = Arc::new(test_utils::TestChannelMonitor{});
+               let tx_broadcaster_1 = Arc::new(test_utils::TestBroadcaster{txn_broadcasted: Mutex::new(Vec::new())});
                let node_id_1 = {
                        let mut key_slice = [0; 32];
                        rng.fill_bytes(&mut key_slice);
                        SecretKey::from_slice(&secp_ctx, &key_slice).unwrap()
                };
-               let node_1 = ChannelManager::new(node_id_1.clone(), 0, true, Network::Testnet, feeest_1.clone(), chan_monitor_1.clone(), chain_monitor_1.clone()).unwrap();
+               let node_1 = ChannelManager::new(node_id_1.clone(), 0, true, Network::Testnet, feeest_1.clone(), chan_monitor_1.clone(), chain_monitor_1.clone(), tx_broadcaster_1.clone()).unwrap();
                let router_1 = Router::new(PublicKey::from_secret_key(&secp_ctx, &node_id_1).unwrap());
 
                let feeest_2 = Arc::new(test_utils::TestFeeEstimator { sat_per_vbyte: 1 });
                let chain_monitor_2 = Arc::new(chaininterface::ChainWatchInterfaceUtil::new());
                let chan_monitor_2 = Arc::new(test_utils::TestChannelMonitor{});
+               let tx_broadcaster_2 = Arc::new(test_utils::TestBroadcaster{txn_broadcasted: Mutex::new(Vec::new())});
                let node_id_2 = {
                        let mut key_slice = [0; 32];
                        rng.fill_bytes(&mut key_slice);
                        SecretKey::from_slice(&secp_ctx, &key_slice).unwrap()
                };
-               let node_2 = ChannelManager::new(node_id_2.clone(), 0, true, Network::Testnet, feeest_2.clone(), chan_monitor_2.clone(), chain_monitor_2.clone()).unwrap();
+               let node_2 = ChannelManager::new(node_id_2.clone(), 0, true, Network::Testnet, feeest_2.clone(), chan_monitor_2.clone(), chain_monitor_2.clone(), tx_broadcaster_2.clone()).unwrap();
                let router_2 = Router::new(PublicKey::from_secret_key(&secp_ctx, &node_id_2).unwrap());
 
                let feeest_3 = Arc::new(test_utils::TestFeeEstimator { sat_per_vbyte: 1 });
                let chain_monitor_3 = Arc::new(chaininterface::ChainWatchInterfaceUtil::new());
                let chan_monitor_3 = Arc::new(test_utils::TestChannelMonitor{});
+               let tx_broadcaster_3 = Arc::new(test_utils::TestBroadcaster{txn_broadcasted: Mutex::new(Vec::new())});
                let node_id_3 = {
                        let mut key_slice = [0; 32];
                        rng.fill_bytes(&mut key_slice);
                        SecretKey::from_slice(&secp_ctx, &key_slice).unwrap()
                };
-               let node_3 = ChannelManager::new(node_id_3.clone(), 0, true, Network::Testnet, feeest_3.clone(), chan_monitor_3.clone(), chain_monitor_3.clone()).unwrap();
+               let node_3 = ChannelManager::new(node_id_3.clone(), 0, true, Network::Testnet, feeest_3.clone(), chan_monitor_3.clone(), chain_monitor_3.clone(), tx_broadcaster_3.clone()).unwrap();
                let router_3 = Router::new(PublicKey::from_secret_key(&secp_ctx, &node_id_3).unwrap());
 
                let feeest_4 = Arc::new(test_utils::TestFeeEstimator { sat_per_vbyte: 1 });
                let chain_monitor_4 = Arc::new(chaininterface::ChainWatchInterfaceUtil::new());
                let chan_monitor_4 = Arc::new(test_utils::TestChannelMonitor{});
+               let tx_broadcaster_4 = Arc::new(test_utils::TestBroadcaster{txn_broadcasted: Mutex::new(Vec::new())});
                let node_id_4 = {
                        let mut key_slice = [0; 32];
                        rng.fill_bytes(&mut key_slice);
                        SecretKey::from_slice(&secp_ctx, &key_slice).unwrap()
                };
-               let node_4 = ChannelManager::new(node_id_4.clone(), 0, true, Network::Testnet, feeest_4.clone(), chan_monitor_4.clone(), chain_monitor_4.clone()).unwrap();
+               let node_4 = ChannelManager::new(node_id_4.clone(), 0, true, Network::Testnet, feeest_4.clone(), chan_monitor_4.clone(), chain_monitor_4.clone(), tx_broadcaster_4.clone()).unwrap();
                let router_4 = Router::new(PublicKey::from_secret_key(&secp_ctx, &node_id_4).unwrap());
 
                // Create some initial channels
@@ -1912,11 +2085,17 @@ mod tests {
                        router.handle_channel_update(&chan_announcement_3.2).unwrap();
                }
 
-               // Send some payments
-               send_payment(&node_1, &router_1, &vec!(&*node_2, &*node_3, &*node_4)[..], 1000000);
+               // Rebalance the network a bit by relaying one payment through all the channels...
+               send_payment(&node_1, &router_1, &vec!(&*node_2, &*node_3, &*node_4)[..], 8000000);
+               send_payment(&node_1, &router_1, &vec!(&*node_2, &*node_3, &*node_4)[..], 8000000);
+               send_payment(&node_1, &router_1, &vec!(&*node_2, &*node_3, &*node_4)[..], 8000000);
+               send_payment(&node_1, &router_1, &vec!(&*node_2, &*node_3, &*node_4)[..], 8000000);
+               send_payment(&node_1, &router_1, &vec!(&*node_2, &*node_3, &*node_4)[..], 8000000);
+
+               // Send some more payments
                send_payment(&node_2, &router_2, &vec!(&*node_3, &*node_4)[..], 1000000);
                send_payment(&node_4, &router_4, &vec!(&*node_3, &*node_2, &*node_1)[..], 1000000);
-               send_payment(&node_4, &router_4, &vec!(&*node_3, &*node_2)[..], 250000);
+               send_payment(&node_4, &router_4, &vec!(&*node_3, &*node_2)[..], 1000000);
 
                // Test failure packets
                send_failed_payment(&node_1, &router_1, &vec!(&*node_2, &*node_3, &*node_4)[..]);
@@ -1930,8 +2109,14 @@ mod tests {
                }
 
                send_payment(&node_1, &router_1, &vec!(&*node_2, &*node_4)[..], 1000000);
-
-               // Rebalance a bit
+               send_payment(&node_3, &router_3, &vec!(&*node_4)[..], 1000000);
+               send_payment(&node_2, &router_2, &vec!(&*node_4)[..], 8000000);
+               send_payment(&node_2, &router_2, &vec!(&*node_4)[..], 8000000);
+               send_payment(&node_2, &router_2, &vec!(&*node_4)[..], 8000000);
+               send_payment(&node_2, &router_2, &vec!(&*node_4)[..], 8000000);
+               send_payment(&node_2, &router_2, &vec!(&*node_4)[..], 8000000);
+
+               // Do some rebalance loop payments, simultaneously
                let mut hops = Vec::with_capacity(3);
                hops.push(RouteHop {
                        pubkey: node_3.get_our_node_id(),
@@ -1948,12 +2133,66 @@ mod tests {
                hops.push(RouteHop {
                        pubkey: node_2.get_our_node_id(),
                        short_channel_id: chan_announcement_4.1.contents.short_channel_id,
-                       fee_msat: 250000,
+                       fee_msat: 1000000,
                        cltv_expiry_delta: 142,
                });
                hops[1].fee_msat = chan_announcement_4.2.contents.fee_base_msat as u64 + chan_announcement_4.2.contents.fee_proportional_millionths as u64 * hops[2].fee_msat as u64 / 1000000;
                hops[0].fee_msat = chan_announcement_3.1.contents.fee_base_msat as u64 + chan_announcement_3.1.contents.fee_proportional_millionths as u64 * hops[1].fee_msat as u64 / 1000000;
-               send_along_route(&node_2, Route { hops }, &vec!(&*node_3, &*node_4, &*node_2)[..], 250000);
+               let payment_preimage_1 = send_along_route(&node_2, Route { hops }, &vec!(&*node_3, &*node_4, &*node_2)[..], 1000000).0;
+
+               let mut hops = Vec::with_capacity(3);
+               hops.push(RouteHop {
+                       pubkey: node_4.get_our_node_id(),
+                       short_channel_id: chan_announcement_4.1.contents.short_channel_id,
+                       fee_msat: 0,
+                       cltv_expiry_delta: chan_announcement_3.2.contents.cltv_expiry_delta as u32
+               });
+               hops.push(RouteHop {
+                       pubkey: node_3.get_our_node_id(),
+                       short_channel_id: chan_announcement_3.1.contents.short_channel_id,
+                       fee_msat: 0,
+                       cltv_expiry_delta: chan_announcement_2.2.contents.cltv_expiry_delta as u32
+               });
+               hops.push(RouteHop {
+                       pubkey: node_2.get_our_node_id(),
+                       short_channel_id: chan_announcement_2.1.contents.short_channel_id,
+                       fee_msat: 1000000,
+                       cltv_expiry_delta: 142,
+               });
+               hops[1].fee_msat = chan_announcement_2.2.contents.fee_base_msat as u64 + chan_announcement_2.2.contents.fee_proportional_millionths as u64 * hops[2].fee_msat as u64 / 1000000;
+               hops[0].fee_msat = chan_announcement_3.2.contents.fee_base_msat as u64 + chan_announcement_3.2.contents.fee_proportional_millionths as u64 * hops[1].fee_msat as u64 / 1000000;
+               let payment_preimage_2 = send_along_route(&node_2, Route { hops }, &vec!(&*node_4, &*node_3, &*node_2)[..], 1000000).0;
+
+               // Claim the rebalances...
+               claim_payment(&node_2, &vec!(&*node_4, &*node_3, &*node_2)[..], payment_preimage_2);
+               claim_payment(&node_2, &vec!(&*node_3, &*node_4, &*node_2)[..], payment_preimage_1);
+
+               // Add a duplicate new channel from 2 to 4
+               let chan_announcement_5 = create_chan_between_nodes(&node_2, &chain_monitor_2, &node_4, &chain_monitor_4);
+               for router in vec!(&router_1, &router_2, &router_3, &router_4) {
+                       assert!(router.handle_channel_announcement(&chan_announcement_5.0).unwrap());
+                       router.handle_channel_update(&chan_announcement_5.1).unwrap();
+                       router.handle_channel_update(&chan_announcement_5.2).unwrap();
+               }
+
+               // Send some payments across both channels
+               let payment_preimage_3 = route_payment(&node_1, &router_1, &vec!(&*node_2, &*node_4)[..], 3000000).0;
+               let payment_preimage_4 = route_payment(&node_1, &router_1, &vec!(&*node_2, &*node_4)[..], 3000000).0;
+               let payment_preimage_5 = route_payment(&node_1, &router_1, &vec!(&*node_2, &*node_4)[..], 3000000).0;
+
+               route_over_limit(&node_1, &router_1, &vec!(&*node_2, &*node_4)[..], 3000000);
+
+               //TODO: Test that routes work again here as we've been notified that the channel is full
+
+               claim_payment(&node_1, &vec!(&*node_2, &*node_4)[..], payment_preimage_3);
+               claim_payment(&node_1, &vec!(&*node_2, &*node_4)[..], payment_preimage_4);
+               claim_payment(&node_1, &vec!(&*node_2, &*node_4)[..], payment_preimage_5);
+
+               // Close down the channels...
+               close_channel(&node_1, &tx_broadcaster_1, &node_2, &tx_broadcaster_2, &chan_announcement_1.3, true);
+               close_channel(&node_2, &tx_broadcaster_2, &node_3, &tx_broadcaster_3, &chan_announcement_2.3, false);
+               close_channel(&node_3, &tx_broadcaster_3, &node_4, &tx_broadcaster_4, &chan_announcement_3.3, true);
+               close_channel(&node_2, &tx_broadcaster_2, &node_4, &tx_broadcaster_4, &chan_announcement_4.3, false);
 
                // Check that we processed all pending events
                for node in vec!(&node_1, &node_2, &node_3, &node_4) {