Introduce EnforcementState for EnforcingSigner
[rust-lightning] / fuzz / src / chanmon_consistency.rs
index 9d0a90ee1cdc0736ea6e3384348136eaef44c9a8..88826d65570fb94c7cfda47de7cfa58c53e5027e 100644 (file)
@@ -30,23 +30,24 @@ use bitcoin::hashes::sha256::Hash as Sha256;
 use bitcoin::hash_types::{BlockHash, WPubkeyHash};
 
 use lightning::chain;
-use lightning::chain::chainmonitor;
-use lightning::chain::channelmonitor;
+use lightning::chain::{BestBlock, chainmonitor, channelmonitor, Confirm, Watch};
 use lightning::chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdateErr, MonitorEvent};
 use lightning::chain::transaction::OutPoint;
 use lightning::chain::chaininterface::{BroadcasterInterface, ConfirmationTarget, FeeEstimator};
 use lightning::chain::keysinterface::{KeysInterface, InMemorySigner};
-use lightning::ln::channelmanager::{BestBlock, ChainParameters, ChannelManager, PaymentHash, PaymentPreimage, PaymentSecret, PaymentSendFailure, ChannelManagerReadArgs};
+use lightning::ln::{PaymentHash, PaymentPreimage, PaymentSecret};
+use lightning::ln::channelmanager::{ChainParameters, ChannelManager, PaymentSendFailure, ChannelManagerReadArgs};
+use lightning::ln::channel::FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE;
 use lightning::ln::features::{ChannelFeatures, InitFeatures, NodeFeatures};
-use lightning::ln::msgs::{CommitmentUpdate, ChannelMessageHandler, DecodeError, ErrorAction, UpdateAddHTLC, Init};
-use lightning::util::enforcing_trait_impls::{EnforcingSigner, INITIAL_REVOKED_COMMITMENT_NUMBER};
+use lightning::ln::msgs::{CommitmentUpdate, ChannelMessageHandler, DecodeError, UpdateAddHTLC, Init};
+use lightning::ln::script::ShutdownScript;
+use lightning::util::enforcing_trait_impls::{EnforcingSigner, EnforcementState};
 use lightning::util::errors::APIError;
 use lightning::util::events;
 use lightning::util::logger::Logger;
 use lightning::util::config::UserConfig;
-use lightning::util::events::{EventsProvider, MessageSendEventsProvider};
+use lightning::util::events::MessageSendEventsProvider;
 use lightning::util::ser::{Readable, ReadableArgs, Writeable, Writer};
-use lightning::util::test_utils::OnlyReadsKeysInterface;
 use lightning::routing::router::{Route, RouteHop};
 
 
@@ -54,19 +55,31 @@ use utils::test_logger;
 use utils::test_persister::TestPersister;
 
 use bitcoin::secp256k1::key::{PublicKey,SecretKey};
+use bitcoin::secp256k1::recovery::RecoverableSignature;
 use bitcoin::secp256k1::Secp256k1;
 
 use std::mem;
-use std::cmp::Ordering;
+use std::cmp::{self, Ordering};
 use std::collections::{HashSet, hash_map, HashMap};
 use std::sync::{Arc,Mutex};
 use std::sync::atomic;
 use std::io::Cursor;
 
-struct FuzzEstimator {}
+const MAX_FEE: u32 = 10_000;
+struct FuzzEstimator {
+       ret_val: atomic::AtomicU32,
+}
 impl FeeEstimator for FuzzEstimator {
-       fn get_est_sat_per_1000_weight(&self, _: ConfirmationTarget) -> u32 {
-               253
+       fn get_est_sat_per_1000_weight(&self, conf_target: ConfirmationTarget) -> u32 {
+               // We force-close channels if our counterparty sends us a feerate which is a small multiple
+               // of our HighPriority fee estimate or smaller than our Background fee estimate. Thus, we
+               // always return a HighPriority feerate here which is >= the maximum Normal feerate and a
+               // Background feerate which is <= the minimum Normal feerate.
+               match conf_target {
+                       ConfirmationTarget::HighPriority => MAX_FEE,
+                       ConfirmationTarget::Background => 253,
+                       ConfirmationTarget::Normal => cmp::min(self.ret_val.load(atomic::Ordering::Acquire), MAX_FEE),
+               }
        }
 }
 
@@ -88,6 +101,7 @@ impl Writer for VecWriter {
 
 struct TestChainMonitor {
        pub logger: Arc<dyn Logger>,
+       pub keys: Arc<KeyProvider>,
        pub chain_monitor: Arc<chainmonitor::ChainMonitor<EnforcingSigner, Arc<dyn chain::Filter>, Arc<TestBroadcaster>, Arc<FuzzEstimator>, Arc<dyn Logger>, Arc<TestPersister>>>,
        pub update_ret: Mutex<Result<(), channelmonitor::ChannelMonitorUpdateErr>>,
        // If we reload a node with an old copy of ChannelMonitors, the ChannelManager deserialization
@@ -99,10 +113,11 @@ struct TestChainMonitor {
        pub should_update_manager: atomic::AtomicBool,
 }
 impl TestChainMonitor {
-       pub fn new(broadcaster: Arc<TestBroadcaster>, logger: Arc<dyn Logger>, feeest: Arc<FuzzEstimator>, persister: Arc<TestPersister>) -> Self {
+       pub fn new(broadcaster: Arc<TestBroadcaster>, logger: Arc<dyn Logger>, feeest: Arc<FuzzEstimator>, persister: Arc<TestPersister>, keys: Arc<KeyProvider>) -> Self {
                Self {
                        chain_monitor: Arc::new(chainmonitor::ChainMonitor::new(None, broadcaster, logger.clone(), feeest, persister)),
                        logger,
+                       keys,
                        update_ret: Mutex::new(Ok(())),
                        latest_monitors: Mutex::new(HashMap::new()),
                        should_update_manager: atomic::AtomicBool::new(false),
@@ -128,12 +143,13 @@ impl chain::Watch<EnforcingSigner> for TestChainMonitor {
                        hash_map::Entry::Vacant(_) => panic!("Didn't have monitor on update call"),
                };
                let deserialized_monitor = <(BlockHash, channelmonitor::ChannelMonitor<EnforcingSigner>)>::
-                       read(&mut Cursor::new(&map_entry.get().1), &OnlyReadsKeysInterface {}).unwrap().1;
-               deserialized_monitor.update_monitor(&update, &&TestBroadcaster{}, &&FuzzEstimator{}, &self.logger).unwrap();
+                       read(&mut Cursor::new(&map_entry.get().1), &*self.keys).unwrap().1;
+               deserialized_monitor.update_monitor(&update, &&TestBroadcaster{}, &&FuzzEstimator { ret_val: atomic::AtomicU32::new(253) }, &self.logger).unwrap();
                let mut ser = VecWriter(Vec::new());
                deserialized_monitor.write(&mut ser).unwrap();
                map_entry.insert((update.update_id, ser.0));
                self.should_update_manager.store(true, atomic::Ordering::Relaxed);
+               assert!(self.chain_monitor.update_channel(funding_txo, update).is_ok());
                self.update_ret.lock().unwrap().clone()
        }
 
@@ -144,8 +160,8 @@ impl chain::Watch<EnforcingSigner> for TestChainMonitor {
 
 struct KeyProvider {
        node_id: u8,
-       rand_bytes_id: atomic::AtomicU8,
-       revoked_commitments: Mutex<HashMap<[u8;32], Arc<Mutex<u64>>>>,
+       rand_bytes_id: atomic::AtomicU32,
+       enforcement_states: Mutex<HashMap<[u8;32], Arc<Mutex<EnforcementState>>>>,
 }
 impl KeysInterface for KeyProvider {
        type Signer = EnforcingSigner;
@@ -161,9 +177,11 @@ impl KeysInterface for KeyProvider {
                Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&our_channel_monitor_claim_key_hash[..]).into_script()
        }
 
-       fn get_shutdown_pubkey(&self) -> PublicKey {
+       fn get_shutdown_scriptpubkey(&self) -> ShutdownScript {
                let secp_ctx = Secp256k1::signing_only();
-               PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, self.node_id]).unwrap())
+               let secret_key = SecretKey::from_slice(&[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, self.node_id]).unwrap();
+               let pubkey_hash = WPubkeyHash::hash(&PublicKey::from_secret_key(&secp_ctx, &secret_key).serialize());
+               ShutdownScript::new_p2wpkh(&pubkey_hash)
        }
 
        fn get_channel_signer(&self, _inbound: bool, channel_value_satoshis: u64) -> EnforcingSigner {
@@ -176,41 +194,44 @@ impl KeysInterface for KeyProvider {
                        SecretKey::from_slice(&[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 6, self.node_id]).unwrap(),
                        SecretKey::from_slice(&[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 7, self.node_id]).unwrap(),
                        SecretKey::from_slice(&[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8, self.node_id]).unwrap(),
-                       [id, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 9, self.node_id],
+                       [id as u8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 9, self.node_id],
                        channel_value_satoshis,
                        [0; 32],
                );
-               let revoked_commitment = self.make_revoked_commitment_cell(keys.commitment_seed);
+               let revoked_commitment = self.make_enforcement_state_cell(keys.commitment_seed);
                EnforcingSigner::new_with_revoked(keys, revoked_commitment, false)
        }
 
        fn get_secure_random_bytes(&self) -> [u8; 32] {
                let id = self.rand_bytes_id.fetch_add(1, atomic::Ordering::Relaxed);
-               [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, id, 11, self.node_id]
+               let mut res = [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 11, self.node_id];
+               res[30-4..30].copy_from_slice(&id.to_le_bytes());
+               res
        }
 
        fn read_chan_signer(&self, buffer: &[u8]) -> Result<Self::Signer, DecodeError> {
                let mut reader = std::io::Cursor::new(buffer);
 
                let inner: InMemorySigner = Readable::read(&mut reader)?;
-               let revoked_commitment = self.make_revoked_commitment_cell(inner.commitment_seed);
-
-               let last_commitment_number = Readable::read(&mut reader)?;
+               let state = self.make_enforcement_state_cell(inner.commitment_seed);
 
                Ok(EnforcingSigner {
                        inner,
-                       last_commitment_number: Arc::new(Mutex::new(last_commitment_number)),
-                       revoked_commitment,
+                       state,
                        disable_revocation_policy_check: false,
                })
        }
+
+       fn sign_invoice(&self, _invoice_preimage: Vec<u8>) -> Result<RecoverableSignature, ()> {
+               unreachable!()
+       }
 }
 
 impl KeyProvider {
-       fn make_revoked_commitment_cell(&self, commitment_seed: [u8; 32]) -> Arc<Mutex<u64>> {
-               let mut revoked_commitments = self.revoked_commitments.lock().unwrap();
+       fn make_enforcement_state_cell(&self, commitment_seed: [u8; 32]) -> Arc<Mutex<EnforcementState>> {
+               let mut revoked_commitments = self.enforcement_states.lock().unwrap();
                if !revoked_commitments.contains_key(&commitment_seed) {
-                       revoked_commitments.insert(commitment_seed, Arc::new(Mutex::new(INITIAL_REVOKED_COMMITMENT_NUMBER)));
+                       revoked_commitments.insert(commitment_seed, Arc::new(Mutex::new(EnforcementState::new())));
                }
                let cell = revoked_commitments.get(&commitment_seed).unwrap();
                Arc::clone(cell)
@@ -232,14 +253,17 @@ fn check_api_err(api_err: APIError) {
                                _ if err.starts_with("Cannot push more than their max accepted HTLCs ") => {},
                                _ if err.starts_with("Cannot send value that would put us over the max HTLC value in flight our peer will accept ") => {},
                                _ if err.starts_with("Cannot send value that would put our balance under counterparty-announced channel reserve value") => {},
+                               _ if err.starts_with("Cannot send value that would put counterparty balance under holder-announced channel reserve value") => {},
                                _ if err.starts_with("Cannot send value that would overdraw remaining funds.") => {},
                                _ if err.starts_with("Cannot send value that would not leave enough to pay for fees.") => {},
+                               _ if err.starts_with("Cannot send value that would put our exposure to dust HTLCs at") => {},
                                _ => panic!("{}", err),
                        }
                },
                APIError::MonitorUpdateFailed => {
                        // We can (obviously) temp-fail a monitor update
                },
+               APIError::IncompatibleShutdownScript { .. } => panic!("Cannot send an incompatible shutdown script"),
        }
 }
 #[inline]
@@ -260,45 +284,58 @@ fn check_payment_err(send_err: PaymentSendFailure) {
 
 type ChanMan = ChannelManager<EnforcingSigner, Arc<TestChainMonitor>, Arc<TestBroadcaster>, Arc<KeyProvider>, Arc<FuzzEstimator>, Arc<dyn Logger>>;
 
+#[inline]
+fn get_payment_secret_hash(dest: &ChanMan, payment_id: &mut u8) -> Option<(PaymentSecret, PaymentHash)> {
+       let mut payment_hash;
+       for _ in 0..256 {
+               payment_hash = PaymentHash(Sha256::hash(&[*payment_id; 1]).into_inner());
+               if let Ok(payment_secret) = dest.create_inbound_payment_for_hash(payment_hash, None, 3600, 0) {
+                       return Some((payment_secret, payment_hash));
+               }
+               *payment_id = payment_id.wrapping_add(1);
+       }
+       None
+}
+
 #[inline]
 fn send_payment(source: &ChanMan, dest: &ChanMan, dest_chan_id: u64, amt: u64, payment_id: &mut u8) -> bool {
-       let payment_hash = Sha256::hash(&[*payment_id; 1]);
-       *payment_id = payment_id.wrapping_add(1);
+       let (payment_secret, payment_hash) =
+               if let Some((secret, hash)) = get_payment_secret_hash(dest, payment_id) { (secret, hash) } else { return true; };
        if let Err(err) = source.send_payment(&Route {
                paths: vec![vec![RouteHop {
                        pubkey: dest.get_our_node_id(),
-                       node_features: NodeFeatures::empty(),
+                       node_features: NodeFeatures::known(),
                        short_channel_id: dest_chan_id,
-                       channel_features: ChannelFeatures::empty(),
+                       channel_features: ChannelFeatures::known(),
                        fee_msat: amt,
                        cltv_expiry_delta: 200,
                }]],
-       }, PaymentHash(payment_hash.into_inner()), &None) {
+       }, payment_hash, &Some(payment_secret)) {
                check_payment_err(err);
                false
        } else { true }
 }
 #[inline]
 fn send_hop_payment(source: &ChanMan, middle: &ChanMan, middle_chan_id: u64, dest: &ChanMan, dest_chan_id: u64, amt: u64, payment_id: &mut u8) -> bool {
-       let payment_hash = Sha256::hash(&[*payment_id; 1]);
-       *payment_id = payment_id.wrapping_add(1);
+       let (payment_secret, payment_hash) =
+               if let Some((secret, hash)) = get_payment_secret_hash(dest, payment_id) { (secret, hash) } else { return true; };
        if let Err(err) = source.send_payment(&Route {
                paths: vec![vec![RouteHop {
                        pubkey: middle.get_our_node_id(),
-                       node_features: NodeFeatures::empty(),
+                       node_features: NodeFeatures::known(),
                        short_channel_id: middle_chan_id,
-                       channel_features: ChannelFeatures::empty(),
+                       channel_features: ChannelFeatures::known(),
                        fee_msat: 50000,
                        cltv_expiry_delta: 100,
                },RouteHop {
                        pubkey: dest.get_our_node_id(),
-                       node_features: NodeFeatures::empty(),
+                       node_features: NodeFeatures::known(),
                        short_channel_id: dest_chan_id,
-                       channel_features: ChannelFeatures::empty(),
+                       channel_features: ChannelFeatures::known(),
                        fee_msat: amt,
                        cltv_expiry_delta: 200,
                }]],
-       }, PaymentHash(payment_hash.into_inner()), &None) {
+       }, payment_hash, &Some(payment_secret)) {
                check_payment_err(err);
                false
        } else { true }
@@ -306,44 +343,41 @@ fn send_hop_payment(source: &ChanMan, middle: &ChanMan, middle_chan_id: u64, des
 
 #[inline]
 pub fn do_test<Out: test_logger::Output>(data: &[u8], out: Out) {
-       let fee_est = Arc::new(FuzzEstimator{});
        let broadcast = Arc::new(TestBroadcaster{});
 
        macro_rules! make_node {
-               ($node_id: expr) => { {
+               ($node_id: expr, $fee_estimator: expr) => { {
                        let logger: Arc<dyn Logger> = Arc::new(test_logger::TestLogger::new($node_id.to_string(), out.clone()));
-                       let monitor = Arc::new(TestChainMonitor::new(broadcast.clone(), logger.clone(), fee_est.clone(), Arc::new(TestPersister{})));
+                       let keys_manager = Arc::new(KeyProvider { node_id: $node_id, rand_bytes_id: atomic::AtomicU32::new(0), enforcement_states: Mutex::new(HashMap::new()) });
+                       let monitor = Arc::new(TestChainMonitor::new(broadcast.clone(), logger.clone(), $fee_estimator.clone(), Arc::new(TestPersister{}), Arc::clone(&keys_manager)));
 
-                       let keys_manager = Arc::new(KeyProvider { node_id: $node_id, rand_bytes_id: atomic::AtomicU8::new(0), revoked_commitments: Mutex::new(HashMap::new()) });
                        let mut config = UserConfig::default();
-                       config.channel_options.fee_proportional_millionths = 0;
+                       config.channel_options.forwarding_fee_proportional_millionths = 0;
                        config.channel_options.announced_channel = true;
-                       config.peer_channel_config_limits.min_dust_limit_satoshis = 0;
                        let network = Network::Bitcoin;
                        let params = ChainParameters {
                                network,
                                best_block: BestBlock::from_genesis(network),
                        };
-                       (ChannelManager::new(fee_est.clone(), monitor.clone(), broadcast.clone(), Arc::clone(&logger), keys_manager.clone(), config, params),
+                       (ChannelManager::new($fee_estimator.clone(), monitor.clone(), broadcast.clone(), Arc::clone(&logger), keys_manager.clone(), config, params),
                        monitor, keys_manager)
                } }
        }
 
        macro_rules! reload_node {
-               ($ser: expr, $node_id: expr, $old_monitors: expr, $keys_manager: expr) => { {
+               ($ser: expr, $node_id: expr, $old_monitors: expr, $keys_manager: expr, $fee_estimator: expr) => { {
                    let keys_manager = Arc::clone(& $keys_manager);
                        let logger: Arc<dyn Logger> = Arc::new(test_logger::TestLogger::new($node_id.to_string(), out.clone()));
-                       let chain_monitor = Arc::new(TestChainMonitor::new(broadcast.clone(), logger.clone(), fee_est.clone(), Arc::new(TestPersister{})));
+                       let chain_monitor = Arc::new(TestChainMonitor::new(broadcast.clone(), logger.clone(), $fee_estimator.clone(), Arc::new(TestPersister{}), Arc::clone(& $keys_manager)));
 
                        let mut config = UserConfig::default();
-                       config.channel_options.fee_proportional_millionths = 0;
+                       config.channel_options.forwarding_fee_proportional_millionths = 0;
                        config.channel_options.announced_channel = true;
-                       config.peer_channel_config_limits.min_dust_limit_satoshis = 0;
 
                        let mut monitors = HashMap::new();
                        let mut old_monitors = $old_monitors.latest_monitors.lock().unwrap();
                        for (outpoint, (update_id, monitor_ser)) in old_monitors.drain() {
-                               monitors.insert(outpoint, <(BlockHash, ChannelMonitor<EnforcingSigner>)>::read(&mut Cursor::new(&monitor_ser), &OnlyReadsKeysInterface {}).expect("Failed to read monitor").1);
+                               monitors.insert(outpoint, <(BlockHash, ChannelMonitor<EnforcingSigner>)>::read(&mut Cursor::new(&monitor_ser), &*$keys_manager).expect("Failed to read monitor").1);
                                chain_monitor.latest_monitors.lock().unwrap().insert(outpoint, (update_id, monitor_ser));
                        }
                        let mut monitor_refs = HashMap::new();
@@ -353,7 +387,7 @@ pub fn do_test<Out: test_logger::Output>(data: &[u8], out: Out) {
 
                        let read_args = ChannelManagerReadArgs {
                                keys_manager,
-                               fee_estimator: fee_est.clone(),
+                               fee_estimator: $fee_estimator.clone(),
                                chain_monitor: chain_monitor.clone(),
                                tx_broadcaster: broadcast.clone(),
                                logger,
@@ -361,13 +395,20 @@ pub fn do_test<Out: test_logger::Output>(data: &[u8], out: Out) {
                                channel_monitors: monitor_refs,
                        };
 
-                       (<(BlockHash, ChanMan)>::read(&mut Cursor::new(&$ser.0), read_args).expect("Failed to read manager").1, chain_monitor)
+                       let res = (<(BlockHash, ChanMan)>::read(&mut Cursor::new(&$ser.0), read_args).expect("Failed to read manager").1, chain_monitor.clone());
+                       for (funding_txo, mon) in monitors.drain() {
+                               assert!(chain_monitor.chain_monitor.watch_channel(funding_txo, mon).is_ok());
+                       }
+                       res
                } }
        }
 
        let mut channel_txn = Vec::new();
        macro_rules! make_channel {
                ($source: expr, $dest: expr, $chan_id: expr) => { {
+                       $source.peer_connected(&$dest.get_our_node_id(), &Init { features: InitFeatures::known() });
+                       $dest.peer_connected(&$source.get_our_node_id(), &Init { features: InitFeatures::known() });
+
                        $source.create_channel($dest.get_our_node_id(), 100_000, 42, 0, None).unwrap();
                        let open_channel = {
                                let events = $source.get_and_clear_pending_msg_events();
@@ -428,11 +469,11 @@ pub fn do_test<Out: test_logger::Output>(data: &[u8], out: Out) {
                        let chain_hash = genesis_block(Network::Bitcoin).block_hash();
                        let mut header = BlockHeader { version: 0x20000000, prev_blockhash: chain_hash, merkle_root: Default::default(), time: 42, bits: 42, nonce: 42 };
                        let txdata: Vec<_> = channel_txn.iter().enumerate().map(|(i, tx)| (i + 1, tx)).collect();
-                       $node.transactions_confirmed(&header, 1, &txdata);
+                       $node.transactions_confirmed(&header, &txdata, 1);
                        for _ in 2..100 {
                                header = BlockHeader { version: 0x20000000, prev_blockhash: header.block_hash(), merkle_root: Default::default(), time: 42, bits: 42, nonce: 42 };
                        }
-                       $node.update_best_block(&header, 99);
+                       $node.best_block_updated(&header, 99);
                } }
        }
 
@@ -464,11 +505,18 @@ pub fn do_test<Out: test_logger::Output>(data: &[u8], out: Out) {
                } }
        }
 
+       let fee_est_a = Arc::new(FuzzEstimator { ret_val: atomic::AtomicU32::new(253) });
+       let mut last_htlc_clear_fee_a =  253;
+       let fee_est_b = Arc::new(FuzzEstimator { ret_val: atomic::AtomicU32::new(253) });
+       let mut last_htlc_clear_fee_b =  253;
+       let fee_est_c = Arc::new(FuzzEstimator { ret_val: atomic::AtomicU32::new(253) });
+       let mut last_htlc_clear_fee_c =  253;
+
        // 3 nodes is enough to hit all the possible cases, notably unknown-source-unknown-dest
        // forwarding.
-       let (node_a, mut monitor_a, keys_manager_a) = make_node!(0);
-       let (node_b, mut monitor_b, keys_manager_b) = make_node!(1);
-       let (node_c, mut monitor_c, keys_manager_c) = make_node!(2);
+       let (node_a, mut monitor_a, keys_manager_a) = make_node!(0, fee_est_a);
+       let (node_b, mut monitor_b, keys_manager_b) = make_node!(1, fee_est_b);
+       let (node_c, mut monitor_c, keys_manager_c) = make_node!(2, fee_est_c);
 
        let mut nodes = [node_a, node_b, node_c];
 
@@ -488,8 +536,10 @@ pub fn do_test<Out: test_logger::Output>(data: &[u8], out: Out) {
 
        let mut chan_a_disconnected = false;
        let mut chan_b_disconnected = false;
+       let mut ab_events = Vec::new();
        let mut ba_events = Vec::new();
        let mut bc_events = Vec::new();
+       let mut cb_events = Vec::new();
 
        let mut node_a_ser = VecWriter(Vec::new());
        nodes[0].write(&mut node_a_ser).unwrap();
@@ -522,68 +572,92 @@ pub fn do_test<Out: test_logger::Output>(data: &[u8], out: Out) {
        }
 
        loop {
-               macro_rules! send_payment_with_secret {
-                       ($source: expr, $middle: expr, $dest: expr) => { {
-                               let payment_hash = Sha256::hash(&[payment_id; 1]);
-                               payment_id = payment_id.wrapping_add(1);
-                               let payment_secret = Sha256::hash(&[payment_id; 1]);
-                               payment_id = payment_id.wrapping_add(1);
-                               if let Err(err) = $source.send_payment(&Route {
-                                       paths: vec![vec![RouteHop {
-                                               pubkey: $middle.0.get_our_node_id(),
-                                               node_features: NodeFeatures::empty(),
-                                               short_channel_id: $middle.1,
-                                               channel_features: ChannelFeatures::empty(),
-                                               fee_msat: 50_000,
-                                               cltv_expiry_delta: 100,
-                                       },RouteHop {
-                                               pubkey: $dest.0.get_our_node_id(),
-                                               node_features: NodeFeatures::empty(),
-                                               short_channel_id: $dest.1,
-                                               channel_features: ChannelFeatures::empty(),
-                                               fee_msat: 10_000_000,
-                                               cltv_expiry_delta: 200,
-                                       }],vec![RouteHop {
-                                               pubkey: $middle.0.get_our_node_id(),
-                                               node_features: NodeFeatures::empty(),
-                                               short_channel_id: $middle.1,
-                                               channel_features: ChannelFeatures::empty(),
-                                               fee_msat: 50_000,
-                                               cltv_expiry_delta: 100,
-                                       },RouteHop {
-                                               pubkey: $dest.0.get_our_node_id(),
-                                               node_features: NodeFeatures::empty(),
-                                               short_channel_id: $dest.1,
-                                               channel_features: ChannelFeatures::empty(),
-                                               fee_msat: 10_000_000,
-                                               cltv_expiry_delta: 200,
-                                       }]],
-                               }, PaymentHash(payment_hash.into_inner()), &Some(PaymentSecret(payment_secret.into_inner()))) {
-                                       check_payment_err(err);
+               // Push any events from Node B onto ba_events and bc_events
+               macro_rules! push_excess_b_events {
+                       ($excess_events: expr, $expect_drop_node: expr) => { {
+                               let a_id = nodes[0].get_our_node_id();
+                               let expect_drop_node: Option<usize> = $expect_drop_node;
+                               let expect_drop_id = if let Some(id) = expect_drop_node { Some(nodes[id].get_our_node_id()) } else { None };
+                               for event in $excess_events {
+                                       let push_a = match event {
+                                               events::MessageSendEvent::UpdateHTLCs { ref node_id, .. } => {
+                                                       if Some(*node_id) == expect_drop_id { panic!("peer_disconnected should drop msgs bound for the disconnected peer"); }
+                                                       *node_id == a_id
+                                               },
+                                               events::MessageSendEvent::SendRevokeAndACK { ref node_id, .. } => {
+                                                       if Some(*node_id) == expect_drop_id { panic!("peer_disconnected should drop msgs bound for the disconnected peer"); }
+                                                       *node_id == a_id
+                                               },
+                                               events::MessageSendEvent::SendChannelReestablish { ref node_id, .. } => {
+                                                       if Some(*node_id) == expect_drop_id { panic!("peer_disconnected should drop msgs bound for the disconnected peer"); }
+                                                       *node_id == a_id
+                                               },
+                                               events::MessageSendEvent::SendFundingLocked { .. } => continue,
+                                               events::MessageSendEvent::SendAnnouncementSignatures { .. } => continue,
+                                               events::MessageSendEvent::PaymentFailureNetworkUpdate { .. } => continue,
+                                               events::MessageSendEvent::SendChannelUpdate { ref node_id, ref msg } => {
+                                                       assert_eq!(msg.contents.flags & 2, 0); // The disable bit must never be set!
+                                                       if Some(*node_id) == expect_drop_id { panic!("peer_disconnected should drop msgs bound for the disconnected peer"); }
+                                                       *node_id == a_id
+                                               },
+                                               _ => panic!("Unhandled message event {:?}", event),
+                                       };
+                                       if push_a { ba_events.push(event); } else { bc_events.push(event); }
                                }
                        } }
                }
 
+               // While delivering messages, we select across three possible message selection processes
+               // to ensure we get as much coverage as possible. See the individual enum variants for more
+               // details.
+               #[derive(PartialEq)]
+               enum ProcessMessages {
+                       /// Deliver all available messages, including fetching any new messages from
+                       /// `get_and_clear_pending_msg_events()` (which may have side effects).
+                       AllMessages,
+                       /// Call `get_and_clear_pending_msg_events()` first, and then deliver up to one
+                       /// message (which may already be queued).
+                       OneMessage,
+                       /// Deliver up to one already-queued message. This avoids any potential side-effects
+                       /// of `get_and_clear_pending_msg_events()` (eg freeing the HTLC holding cell), which
+                       /// provides potentially more coverage.
+                       OnePendingMessage,
+               }
+
                macro_rules! process_msg_events {
-                       ($node: expr, $corrupt_forward: expr) => { {
-                               let events = if $node == 1 {
+                       ($node: expr, $corrupt_forward: expr, $limit_events: expr) => { {
+                               let mut events = if $node == 1 {
                                        let mut new_events = Vec::new();
                                        mem::swap(&mut new_events, &mut ba_events);
                                        new_events.extend_from_slice(&bc_events[..]);
                                        bc_events.clear();
                                        new_events
-                               } else { Vec::new() };
+                               } else if $node == 0 {
+                                       let mut new_events = Vec::new();
+                                       mem::swap(&mut new_events, &mut ab_events);
+                                       new_events
+                               } else {
+                                       let mut new_events = Vec::new();
+                                       mem::swap(&mut new_events, &mut cb_events);
+                                       new_events
+                               };
+                               let mut new_events = Vec::new();
+                               if $limit_events != ProcessMessages::OnePendingMessage {
+                                       new_events = nodes[$node].get_and_clear_pending_msg_events();
+                               }
                                let mut had_events = false;
-                               for event in events.iter().chain(nodes[$node].get_and_clear_pending_msg_events().iter()) {
+                               let mut events_iter = events.drain(..).chain(new_events.drain(..));
+                               let mut extra_ev = None;
+                               for event in &mut events_iter {
                                        had_events = true;
                                        match event {
-                                               events::MessageSendEvent::UpdateHTLCs { ref node_id, updates: CommitmentUpdate { ref update_add_htlcs, ref update_fail_htlcs, ref update_fulfill_htlcs, ref update_fail_malformed_htlcs, ref update_fee, ref commitment_signed } } => {
-                                                       for dest in nodes.iter() {
-                                                               if dest.get_our_node_id() == *node_id {
-                                                                       assert!(update_fee.is_none());
-                                                                       for update_add in update_add_htlcs {
+                                               events::MessageSendEvent::UpdateHTLCs { node_id, updates: CommitmentUpdate { update_add_htlcs, update_fail_htlcs, update_fulfill_htlcs, update_fail_malformed_htlcs, update_fee, commitment_signed } } => {
+                                                       for (idx, dest) in nodes.iter().enumerate() {
+                                                               if dest.get_our_node_id() == node_id {
+                                                                       for update_add in update_add_htlcs.iter() {
+                                                                               out.locked_write(format!("Delivering update_add_htlc to node {}.\n", idx).as_bytes());
                                                                                if !$corrupt_forward {
-                                                                                       dest.handle_update_add_htlc(&nodes[$node].get_our_node_id(), &update_add);
+                                                                                       dest.handle_update_add_htlc(&nodes[$node].get_our_node_id(), update_add);
                                                                                } else {
                                                                                        // Corrupt the update_add_htlc message so that its HMAC
                                                                                        // check will fail and we generate a
@@ -595,29 +669,54 @@ pub fn do_test<Out: test_logger::Output>(data: &[u8], out: Out) {
                                                                                        dest.handle_update_add_htlc(&nodes[$node].get_our_node_id(), &new_msg);
                                                                                }
                                                                        }
-                                                                       for update_fulfill in update_fulfill_htlcs {
-                                                                               dest.handle_update_fulfill_htlc(&nodes[$node].get_our_node_id(), &update_fulfill);
+                                                                       for update_fulfill in update_fulfill_htlcs.iter() {
+                                                                               out.locked_write(format!("Delivering update_fulfill_htlc to node {}.\n", idx).as_bytes());
+                                                                               dest.handle_update_fulfill_htlc(&nodes[$node].get_our_node_id(), update_fulfill);
+                                                                       }
+                                                                       for update_fail in update_fail_htlcs.iter() {
+                                                                               out.locked_write(format!("Delivering update_fail_htlc to node {}.\n", idx).as_bytes());
+                                                                               dest.handle_update_fail_htlc(&nodes[$node].get_our_node_id(), update_fail);
                                                                        }
-                                                                       for update_fail in update_fail_htlcs {
-                                                                               dest.handle_update_fail_htlc(&nodes[$node].get_our_node_id(), &update_fail);
+                                                                       for update_fail_malformed in update_fail_malformed_htlcs.iter() {
+                                                                               out.locked_write(format!("Delivering update_fail_malformed_htlc to node {}.\n", idx).as_bytes());
+                                                                               dest.handle_update_fail_malformed_htlc(&nodes[$node].get_our_node_id(), update_fail_malformed);
                                                                        }
-                                                                       for update_fail_malformed in update_fail_malformed_htlcs {
-                                                                               dest.handle_update_fail_malformed_htlc(&nodes[$node].get_our_node_id(), &update_fail_malformed);
+                                                                       if let Some(msg) = update_fee {
+                                                                               out.locked_write(format!("Delivering update_fee to node {}.\n", idx).as_bytes());
+                                                                               dest.handle_update_fee(&nodes[$node].get_our_node_id(), &msg);
                                                                        }
+                                                                       let processed_change = !update_add_htlcs.is_empty() || !update_fulfill_htlcs.is_empty() ||
+                                                                               !update_fail_htlcs.is_empty() || !update_fail_malformed_htlcs.is_empty();
+                                                                       if $limit_events != ProcessMessages::AllMessages && processed_change {
+                                                                               // If we only want to process some messages, don't deliver the CS until later.
+                                                                               extra_ev = Some(events::MessageSendEvent::UpdateHTLCs { node_id, updates: CommitmentUpdate {
+                                                                                       update_add_htlcs: Vec::new(),
+                                                                                       update_fail_htlcs: Vec::new(),
+                                                                                       update_fulfill_htlcs: Vec::new(),
+                                                                                       update_fail_malformed_htlcs: Vec::new(),
+                                                                                       update_fee: None,
+                                                                                       commitment_signed
+                                                                               } });
+                                                                               break;
+                                                                       }
+                                                                       out.locked_write(format!("Delivering commitment_signed to node {}.\n", idx).as_bytes());
                                                                        dest.handle_commitment_signed(&nodes[$node].get_our_node_id(), &commitment_signed);
+                                                                       break;
                                                                }
                                                        }
                                                },
                                                events::MessageSendEvent::SendRevokeAndACK { ref node_id, ref msg } => {
-                                                       for dest in nodes.iter() {
+                                                       for (idx, dest) in nodes.iter().enumerate() {
                                                                if dest.get_our_node_id() == *node_id {
+                                                                       out.locked_write(format!("Delivering revoke_and_ack to node {}.\n", idx).as_bytes());
                                                                        dest.handle_revoke_and_ack(&nodes[$node].get_our_node_id(), msg);
                                                                }
                                                        }
                                                },
                                                events::MessageSendEvent::SendChannelReestablish { ref node_id, ref msg } => {
-                                                       for dest in nodes.iter() {
+                                                       for (idx, dest) in nodes.iter().enumerate() {
                                                                if dest.get_our_node_id() == *node_id {
+                                                                       out.locked_write(format!("Delivering channel_reestablish to node {}.\n", idx).as_bytes());
                                                                        dest.handle_channel_reestablish(&nodes[$node].get_our_node_id(), msg);
                                                                }
                                                        }
@@ -625,13 +724,37 @@ pub fn do_test<Out: test_logger::Output>(data: &[u8], out: Out) {
                                                events::MessageSendEvent::SendFundingLocked { .. } => {
                                                        // Can be generated as a reestablish response
                                                },
+                                               events::MessageSendEvent::SendAnnouncementSignatures { .. } => {
+                                                       // Can be generated as a reestablish response
+                                               },
                                                events::MessageSendEvent::PaymentFailureNetworkUpdate { .. } => {
                                                        // Can be generated due to a payment forward being rejected due to a
                                                        // channel having previously failed a monitor update
                                                },
-                                               _ => panic!("Unhandled message event"),
+                                               events::MessageSendEvent::SendChannelUpdate { ref msg, .. } => {
+                                                       // When we reconnect we will resend a channel_update to make sure our
+                                                       // counterparty has the latest parameters for receiving payments
+                                                       // through us. We do, however, check that the message does not include
+                                                       // the "disabled" bit, as we should never ever have a channel which is
+                                                       // disabled when we send such an update (or it may indicate channel
+                                                       // force-close which we should detect as an error).
+                                                       assert_eq!(msg.contents.flags & 2, 0);
+                                               },
+                                               _ => panic!("Unhandled message event {:?}", event),
+                                       }
+                                       if $limit_events != ProcessMessages::AllMessages {
+                                               break;
                                        }
                                }
+                               if $node == 1 {
+                                       push_excess_b_events!(extra_ev.into_iter().chain(events_iter), None);
+                               } else if $node == 0 {
+                                       if let Some(ev) = extra_ev { ab_events.push(ev); }
+                                       for event in events_iter { ab_events.push(event); }
+                               } else {
+                                       if let Some(ev) = extra_ev { cb_events.push(ev); }
+                                       for event in events_iter { cb_events.push(event); }
+                               }
                                had_events
                        } }
                }
@@ -645,11 +768,16 @@ pub fn do_test<Out: test_logger::Output>(data: &[u8], out: Out) {
                                                        events::MessageSendEvent::SendRevokeAndACK { .. } => {},
                                                        events::MessageSendEvent::SendChannelReestablish { .. } => {},
                                                        events::MessageSendEvent::SendFundingLocked { .. } => {},
+                                                       events::MessageSendEvent::SendAnnouncementSignatures { .. } => {},
                                                        events::MessageSendEvent::PaymentFailureNetworkUpdate { .. } => {},
-                                                       events::MessageSendEvent::HandleError { action: ErrorAction::IgnoreError, .. } => {},
+                                                       events::MessageSendEvent::SendChannelUpdate { ref msg, .. } => {
+                                                               assert_eq!(msg.contents.flags & 2, 0); // The disable bit must never be set!
+                                                       },
                                                        _ => panic!("Unhandled message event"),
                                                }
                                        }
+                                       push_excess_b_events!(nodes[1].get_and_clear_pending_msg_events().drain(..), Some(0));
+                                       ab_events.clear();
                                        ba_events.clear();
                                } else {
                                        for event in nodes[2].get_and_clear_pending_msg_events() {
@@ -658,33 +786,17 @@ pub fn do_test<Out: test_logger::Output>(data: &[u8], out: Out) {
                                                        events::MessageSendEvent::SendRevokeAndACK { .. } => {},
                                                        events::MessageSendEvent::SendChannelReestablish { .. } => {},
                                                        events::MessageSendEvent::SendFundingLocked { .. } => {},
+                                                       events::MessageSendEvent::SendAnnouncementSignatures { .. } => {},
                                                        events::MessageSendEvent::PaymentFailureNetworkUpdate { .. } => {},
-                                                       events::MessageSendEvent::HandleError { action: ErrorAction::IgnoreError, .. } => {},
+                                                       events::MessageSendEvent::SendChannelUpdate { ref msg, .. } => {
+                                                               assert_eq!(msg.contents.flags & 2, 0); // The disable bit must never be set!
+                                                       },
                                                        _ => panic!("Unhandled message event"),
                                                }
                                        }
+                                       push_excess_b_events!(nodes[1].get_and_clear_pending_msg_events().drain(..), Some(2));
                                        bc_events.clear();
-                               }
-                               let mut events = nodes[1].get_and_clear_pending_msg_events();
-                               let drop_node_id = if $counterparty_id == 0 { nodes[0].get_our_node_id() } else { nodes[2].get_our_node_id() };
-                               let msg_sink = if $counterparty_id == 0 { &mut bc_events } else { &mut ba_events };
-                               for event in events.drain(..) {
-                                       let push = match event {
-                                               events::MessageSendEvent::UpdateHTLCs { ref node_id, .. } => {
-                                                       if *node_id != drop_node_id { true } else { false }
-                                               },
-                                               events::MessageSendEvent::SendRevokeAndACK { ref node_id, .. } => {
-                                                       if *node_id != drop_node_id { true } else { false }
-                                               },
-                                               events::MessageSendEvent::SendChannelReestablish { ref node_id, .. } => {
-                                                       if *node_id != drop_node_id { true } else { false }
-                                               },
-                                               events::MessageSendEvent::SendFundingLocked { .. } => false,
-                                               events::MessageSendEvent::PaymentFailureNetworkUpdate { .. } => false,
-                                               events::MessageSendEvent::HandleError { action: ErrorAction::IgnoreError, .. } => false,
-                                               _ => panic!("Unhandled message event"),
-                                       };
-                                       if push { msg_sink.push(event); }
+                                       cb_events.clear();
                                }
                        } }
                }
@@ -715,17 +827,18 @@ pub fn do_test<Out: test_logger::Output>(data: &[u8], out: Out) {
                                let had_events = !events.is_empty();
                                for event in events.drain(..) {
                                        match event {
-                                               events::Event::PaymentReceived { payment_hash, payment_secret, amt } => {
+                                               events::Event::PaymentReceived { payment_hash, .. } => {
                                                        if claim_set.insert(payment_hash.0) {
                                                                if $fail {
-                                                                       assert!(nodes[$node].fail_htlc_backwards(&payment_hash, &payment_secret));
+                                                                       assert!(nodes[$node].fail_htlc_backwards(&payment_hash));
                                                                } else {
-                                                                       assert!(nodes[$node].claim_funds(PaymentPreimage(payment_hash.0), &payment_secret, amt));
+                                                                       assert!(nodes[$node].claim_funds(PaymentPreimage(payment_hash.0)));
                                                                }
                                                        }
                                                },
                                                events::Event::PaymentSent { .. } => {},
                                                events::Event::PaymentFailed { .. } => {},
+                                               events::Event::PaymentForwarded { .. } if $node == 1 => {},
                                                events::Event::PendingHTLCsForwardable { .. } => {
                                                        nodes[$node].process_pending_htlc_forwards();
                                                },
@@ -736,7 +849,9 @@ pub fn do_test<Out: test_logger::Output>(data: &[u8], out: Out) {
                        } }
                }
 
-               match get_slice!(1)[0] {
+               let v = get_slice!(1)[0];
+               out.locked_write(format!("READ A BYTE! HANDLING INPUT {:x}...........\n", v).as_bytes());
+               match v {
                        // In general, we keep related message groups close together in binary form, allowing
                        // bit-twiddling mutations to have similar effects. This is probably overkill, but no
                        // harm in doing so.
@@ -787,47 +902,69 @@ pub fn do_test<Out: test_logger::Output>(data: &[u8], out: Out) {
                        },
                        0x0e => {
                                if chan_a_disconnected {
-                                       nodes[0].peer_connected(&nodes[1].get_our_node_id(), &Init { features: InitFeatures::empty() });
-                                       nodes[1].peer_connected(&nodes[0].get_our_node_id(), &Init { features: InitFeatures::empty() });
+                                       nodes[0].peer_connected(&nodes[1].get_our_node_id(), &Init { features: InitFeatures::known() });
+                                       nodes[1].peer_connected(&nodes[0].get_our_node_id(), &Init { features: InitFeatures::known() });
                                        chan_a_disconnected = false;
                                }
                        },
                        0x0f => {
                                if chan_b_disconnected {
-                                       nodes[1].peer_connected(&nodes[2].get_our_node_id(), &Init { features: InitFeatures::empty() });
-                                       nodes[2].peer_connected(&nodes[1].get_our_node_id(), &Init { features: InitFeatures::empty() });
+                                       nodes[1].peer_connected(&nodes[2].get_our_node_id(), &Init { features: InitFeatures::known() });
+                                       nodes[2].peer_connected(&nodes[1].get_our_node_id(), &Init { features: InitFeatures::known() });
                                        chan_b_disconnected = false;
                                }
                        },
 
-                       0x10 => { process_msg_events!(0, true); },
-                       0x11 => { process_msg_events!(0, false); },
-                       0x12 => { process_events!(0, true); },
-                       0x13 => { process_events!(0, false); },
-                       0x14 => { process_msg_events!(1, true); },
-                       0x15 => { process_msg_events!(1, false); },
-                       0x16 => { process_events!(1, true); },
-                       0x17 => { process_events!(1, false); },
-                       0x18 => { process_msg_events!(2, true); },
-                       0x19 => { process_msg_events!(2, false); },
-                       0x1a => { process_events!(2, true); },
-                       0x1b => { process_events!(2, false); },
-
-                       0x1c => {
+                       0x10 => { process_msg_events!(0, true, ProcessMessages::AllMessages); },
+                       0x11 => { process_msg_events!(0, false, ProcessMessages::AllMessages); },
+                       0x12 => { process_msg_events!(0, true, ProcessMessages::OneMessage); },
+                       0x13 => { process_msg_events!(0, false, ProcessMessages::OneMessage); },
+                       0x14 => { process_msg_events!(0, true, ProcessMessages::OnePendingMessage); },
+                       0x15 => { process_msg_events!(0, false, ProcessMessages::OnePendingMessage); },
+
+                       0x16 => { process_events!(0, true); },
+                       0x17 => { process_events!(0, false); },
+
+                       0x18 => { process_msg_events!(1, true, ProcessMessages::AllMessages); },
+                       0x19 => { process_msg_events!(1, false, ProcessMessages::AllMessages); },
+                       0x1a => { process_msg_events!(1, true, ProcessMessages::OneMessage); },
+                       0x1b => { process_msg_events!(1, false, ProcessMessages::OneMessage); },
+                       0x1c => { process_msg_events!(1, true, ProcessMessages::OnePendingMessage); },
+                       0x1d => { process_msg_events!(1, false, ProcessMessages::OnePendingMessage); },
+
+                       0x1e => { process_events!(1, true); },
+                       0x1f => { process_events!(1, false); },
+
+                       0x20 => { process_msg_events!(2, true, ProcessMessages::AllMessages); },
+                       0x21 => { process_msg_events!(2, false, ProcessMessages::AllMessages); },
+                       0x22 => { process_msg_events!(2, true, ProcessMessages::OneMessage); },
+                       0x23 => { process_msg_events!(2, false, ProcessMessages::OneMessage); },
+                       0x24 => { process_msg_events!(2, true, ProcessMessages::OnePendingMessage); },
+                       0x25 => { process_msg_events!(2, false, ProcessMessages::OnePendingMessage); },
+
+                       0x26 => { process_events!(2, true); },
+                       0x27 => { process_events!(2, false); },
+
+                       0x2c => {
                                if !chan_a_disconnected {
                                        nodes[1].peer_disconnected(&nodes[0].get_our_node_id(), false);
                                        chan_a_disconnected = true;
                                        drain_msg_events_on_disconnect!(0);
                                }
-                               let (new_node_a, new_monitor_a) = reload_node!(node_a_ser, 0, monitor_a, keys_manager_a);
+                               if monitor_a.should_update_manager.load(atomic::Ordering::Relaxed) {
+                                       node_a_ser.0.clear();
+                                       nodes[0].write(&mut node_a_ser).unwrap();
+                               }
+                               let (new_node_a, new_monitor_a) = reload_node!(node_a_ser, 0, monitor_a, keys_manager_a, fee_est_a);
                                nodes[0] = new_node_a;
                                monitor_a = new_monitor_a;
                        },
-                       0x1d => {
+                       0x2d => {
                                if !chan_a_disconnected {
                                        nodes[0].peer_disconnected(&nodes[1].get_our_node_id(), false);
                                        chan_a_disconnected = true;
                                        nodes[0].get_and_clear_pending_msg_events();
+                                       ab_events.clear();
                                        ba_events.clear();
                                }
                                if !chan_b_disconnected {
@@ -835,81 +972,110 @@ pub fn do_test<Out: test_logger::Output>(data: &[u8], out: Out) {
                                        chan_b_disconnected = true;
                                        nodes[2].get_and_clear_pending_msg_events();
                                        bc_events.clear();
+                                       cb_events.clear();
                                }
-                               let (new_node_b, new_monitor_b) = reload_node!(node_b_ser, 1, monitor_b, keys_manager_b);
+                               let (new_node_b, new_monitor_b) = reload_node!(node_b_ser, 1, monitor_b, keys_manager_b, fee_est_b);
                                nodes[1] = new_node_b;
                                monitor_b = new_monitor_b;
                        },
-                       0x1e => {
+                       0x2e => {
                                if !chan_b_disconnected {
                                        nodes[1].peer_disconnected(&nodes[2].get_our_node_id(), false);
                                        chan_b_disconnected = true;
                                        drain_msg_events_on_disconnect!(2);
                                }
-                               let (new_node_c, new_monitor_c) = reload_node!(node_c_ser, 2, monitor_c, keys_manager_c);
+                               if monitor_c.should_update_manager.load(atomic::Ordering::Relaxed) {
+                                       node_c_ser.0.clear();
+                                       nodes[2].write(&mut node_c_ser).unwrap();
+                               }
+                               let (new_node_c, new_monitor_c) = reload_node!(node_c_ser, 2, monitor_c, keys_manager_c, fee_est_c);
                                nodes[2] = new_node_c;
                                monitor_c = new_monitor_c;
                        },
 
                        // 1/10th the channel size:
-                       0x20 => { send_payment(&nodes[0], &nodes[1], chan_a, 10_000_000, &mut payment_id); },
-                       0x21 => { send_payment(&nodes[1], &nodes[0], chan_a, 10_000_000, &mut payment_id); },
-                       0x22 => { send_payment(&nodes[1], &nodes[2], chan_b, 10_000_000, &mut payment_id); },
-                       0x23 => { send_payment(&nodes[2], &nodes[1], chan_b, 10_000_000, &mut payment_id); },
-                       0x24 => { send_hop_payment(&nodes[0], &nodes[1], chan_a, &nodes[2], chan_b, 10_000_000, &mut payment_id); },
-                       0x25 => { send_hop_payment(&nodes[2], &nodes[1], chan_b, &nodes[0], chan_a, 10_000_000, &mut payment_id); },
-
-                       0x26 => { send_payment_with_secret!(nodes[0], (&nodes[1], chan_a), (&nodes[2], chan_b)); },
-                       0x27 => { send_payment_with_secret!(nodes[2], (&nodes[1], chan_b), (&nodes[0], chan_a)); },
-
-                       0x28 => { send_payment(&nodes[0], &nodes[1], chan_a, 1_000_000, &mut payment_id); },
-                       0x29 => { send_payment(&nodes[1], &nodes[0], chan_a, 1_000_000, &mut payment_id); },
-                       0x2a => { send_payment(&nodes[1], &nodes[2], chan_b, 1_000_000, &mut payment_id); },
-                       0x2b => { send_payment(&nodes[2], &nodes[1], chan_b, 1_000_000, &mut payment_id); },
-                       0x2c => { send_hop_payment(&nodes[0], &nodes[1], chan_a, &nodes[2], chan_b, 1_000_000, &mut payment_id); },
-                       0x2d => { send_hop_payment(&nodes[2], &nodes[1], chan_b, &nodes[0], chan_a, 1_000_000, &mut payment_id); },
-
-                       0x30 => { send_payment(&nodes[0], &nodes[1], chan_a, 100_000, &mut payment_id); },
-                       0x31 => { send_payment(&nodes[1], &nodes[0], chan_a, 100_000, &mut payment_id); },
-                       0x32 => { send_payment(&nodes[1], &nodes[2], chan_b, 100_000, &mut payment_id); },
-                       0x33 => { send_payment(&nodes[2], &nodes[1], chan_b, 100_000, &mut payment_id); },
-                       0x34 => { send_hop_payment(&nodes[0], &nodes[1], chan_a, &nodes[2], chan_b, 100_000, &mut payment_id); },
-                       0x35 => { send_hop_payment(&nodes[2], &nodes[1], chan_b, &nodes[0], chan_a, 100_000, &mut payment_id); },
-
-                       0x38 => { send_payment(&nodes[0], &nodes[1], chan_a, 10_000, &mut payment_id); },
-                       0x39 => { send_payment(&nodes[1], &nodes[0], chan_a, 10_000, &mut payment_id); },
-                       0x3a => { send_payment(&nodes[1], &nodes[2], chan_b, 10_000, &mut payment_id); },
-                       0x3b => { send_payment(&nodes[2], &nodes[1], chan_b, 10_000, &mut payment_id); },
-                       0x3c => { send_hop_payment(&nodes[0], &nodes[1], chan_a, &nodes[2], chan_b, 10_000, &mut payment_id); },
-                       0x3d => { send_hop_payment(&nodes[2], &nodes[1], chan_b, &nodes[0], chan_a, 10_000, &mut payment_id); },
-
-                       0x40 => { send_payment(&nodes[0], &nodes[1], chan_a, 1_000, &mut payment_id); },
-                       0x41 => { send_payment(&nodes[1], &nodes[0], chan_a, 1_000, &mut payment_id); },
-                       0x42 => { send_payment(&nodes[1], &nodes[2], chan_b, 1_000, &mut payment_id); },
-                       0x43 => { send_payment(&nodes[2], &nodes[1], chan_b, 1_000, &mut payment_id); },
-                       0x44 => { send_hop_payment(&nodes[0], &nodes[1], chan_a, &nodes[2], chan_b, 1_000, &mut payment_id); },
-                       0x45 => { send_hop_payment(&nodes[2], &nodes[1], chan_b, &nodes[0], chan_a, 1_000, &mut payment_id); },
-
-                       0x48 => { send_payment(&nodes[0], &nodes[1], chan_a, 100, &mut payment_id); },
-                       0x49 => { send_payment(&nodes[1], &nodes[0], chan_a, 100, &mut payment_id); },
-                       0x4a => { send_payment(&nodes[1], &nodes[2], chan_b, 100, &mut payment_id); },
-                       0x4b => { send_payment(&nodes[2], &nodes[1], chan_b, 100, &mut payment_id); },
-                       0x4c => { send_hop_payment(&nodes[0], &nodes[1], chan_a, &nodes[2], chan_b, 100, &mut payment_id); },
-                       0x4d => { send_hop_payment(&nodes[2], &nodes[1], chan_b, &nodes[0], chan_a, 100, &mut payment_id); },
-
-                       0x50 => { send_payment(&nodes[0], &nodes[1], chan_a, 10, &mut payment_id); },
-                       0x51 => { send_payment(&nodes[1], &nodes[0], chan_a, 10, &mut payment_id); },
-                       0x52 => { send_payment(&nodes[1], &nodes[2], chan_b, 10, &mut payment_id); },
-                       0x53 => { send_payment(&nodes[2], &nodes[1], chan_b, 10, &mut payment_id); },
-                       0x54 => { send_hop_payment(&nodes[0], &nodes[1], chan_a, &nodes[2], chan_b, 10, &mut payment_id); },
-                       0x55 => { send_hop_payment(&nodes[2], &nodes[1], chan_b, &nodes[0], chan_a, 10, &mut payment_id); },
-
-                       0x58 => { send_payment(&nodes[0], &nodes[1], chan_a, 1, &mut payment_id); },
-                       0x59 => { send_payment(&nodes[1], &nodes[0], chan_a, 1, &mut payment_id); },
-                       0x5a => { send_payment(&nodes[1], &nodes[2], chan_b, 1, &mut payment_id); },
-                       0x5b => { send_payment(&nodes[2], &nodes[1], chan_b, 1, &mut payment_id); },
-                       0x5c => { send_hop_payment(&nodes[0], &nodes[1], chan_a, &nodes[2], chan_b, 1, &mut payment_id); },
-                       0x5d => { send_hop_payment(&nodes[2], &nodes[1], chan_b, &nodes[0], chan_a, 1, &mut payment_id); },
+                       0x30 => { send_payment(&nodes[0], &nodes[1], chan_a, 10_000_000, &mut payment_id); },
+                       0x31 => { send_payment(&nodes[1], &nodes[0], chan_a, 10_000_000, &mut payment_id); },
+                       0x32 => { send_payment(&nodes[1], &nodes[2], chan_b, 10_000_000, &mut payment_id); },
+                       0x33 => { send_payment(&nodes[2], &nodes[1], chan_b, 10_000_000, &mut payment_id); },
+                       0x34 => { send_hop_payment(&nodes[0], &nodes[1], chan_a, &nodes[2], chan_b, 10_000_000, &mut payment_id); },
+                       0x35 => { send_hop_payment(&nodes[2], &nodes[1], chan_b, &nodes[0], chan_a, 10_000_000, &mut payment_id); },
+
+                       0x38 => { send_payment(&nodes[0], &nodes[1], chan_a, 1_000_000, &mut payment_id); },
+                       0x39 => { send_payment(&nodes[1], &nodes[0], chan_a, 1_000_000, &mut payment_id); },
+                       0x3a => { send_payment(&nodes[1], &nodes[2], chan_b, 1_000_000, &mut payment_id); },
+                       0x3b => { send_payment(&nodes[2], &nodes[1], chan_b, 1_000_000, &mut payment_id); },
+                       0x3c => { send_hop_payment(&nodes[0], &nodes[1], chan_a, &nodes[2], chan_b, 1_000_000, &mut payment_id); },
+                       0x3d => { send_hop_payment(&nodes[2], &nodes[1], chan_b, &nodes[0], chan_a, 1_000_000, &mut payment_id); },
+
+                       0x40 => { send_payment(&nodes[0], &nodes[1], chan_a, 100_000, &mut payment_id); },
+                       0x41 => { send_payment(&nodes[1], &nodes[0], chan_a, 100_000, &mut payment_id); },
+                       0x42 => { send_payment(&nodes[1], &nodes[2], chan_b, 100_000, &mut payment_id); },
+                       0x43 => { send_payment(&nodes[2], &nodes[1], chan_b, 100_000, &mut payment_id); },
+                       0x44 => { send_hop_payment(&nodes[0], &nodes[1], chan_a, &nodes[2], chan_b, 100_000, &mut payment_id); },
+                       0x45 => { send_hop_payment(&nodes[2], &nodes[1], chan_b, &nodes[0], chan_a, 100_000, &mut payment_id); },
+
+                       0x48 => { send_payment(&nodes[0], &nodes[1], chan_a, 10_000, &mut payment_id); },
+                       0x49 => { send_payment(&nodes[1], &nodes[0], chan_a, 10_000, &mut payment_id); },
+                       0x4a => { send_payment(&nodes[1], &nodes[2], chan_b, 10_000, &mut payment_id); },
+                       0x4b => { send_payment(&nodes[2], &nodes[1], chan_b, 10_000, &mut payment_id); },
+                       0x4c => { send_hop_payment(&nodes[0], &nodes[1], chan_a, &nodes[2], chan_b, 10_000, &mut payment_id); },
+                       0x4d => { send_hop_payment(&nodes[2], &nodes[1], chan_b, &nodes[0], chan_a, 10_000, &mut payment_id); },
+
+                       0x50 => { send_payment(&nodes[0], &nodes[1], chan_a, 1_000, &mut payment_id); },
+                       0x51 => { send_payment(&nodes[1], &nodes[0], chan_a, 1_000, &mut payment_id); },
+                       0x52 => { send_payment(&nodes[1], &nodes[2], chan_b, 1_000, &mut payment_id); },
+                       0x53 => { send_payment(&nodes[2], &nodes[1], chan_b, 1_000, &mut payment_id); },
+                       0x54 => { send_hop_payment(&nodes[0], &nodes[1], chan_a, &nodes[2], chan_b, 1_000, &mut payment_id); },
+                       0x55 => { send_hop_payment(&nodes[2], &nodes[1], chan_b, &nodes[0], chan_a, 1_000, &mut payment_id); },
+
+                       0x58 => { send_payment(&nodes[0], &nodes[1], chan_a, 100, &mut payment_id); },
+                       0x59 => { send_payment(&nodes[1], &nodes[0], chan_a, 100, &mut payment_id); },
+                       0x5a => { send_payment(&nodes[1], &nodes[2], chan_b, 100, &mut payment_id); },
+                       0x5b => { send_payment(&nodes[2], &nodes[1], chan_b, 100, &mut payment_id); },
+                       0x5c => { send_hop_payment(&nodes[0], &nodes[1], chan_a, &nodes[2], chan_b, 100, &mut payment_id); },
+                       0x5d => { send_hop_payment(&nodes[2], &nodes[1], chan_b, &nodes[0], chan_a, 100, &mut payment_id); },
+
+                       0x60 => { send_payment(&nodes[0], &nodes[1], chan_a, 10, &mut payment_id); },
+                       0x61 => { send_payment(&nodes[1], &nodes[0], chan_a, 10, &mut payment_id); },
+                       0x62 => { send_payment(&nodes[1], &nodes[2], chan_b, 10, &mut payment_id); },
+                       0x63 => { send_payment(&nodes[2], &nodes[1], chan_b, 10, &mut payment_id); },
+                       0x64 => { send_hop_payment(&nodes[0], &nodes[1], chan_a, &nodes[2], chan_b, 10, &mut payment_id); },
+                       0x65 => { send_hop_payment(&nodes[2], &nodes[1], chan_b, &nodes[0], chan_a, 10, &mut payment_id); },
+
+                       0x68 => { send_payment(&nodes[0], &nodes[1], chan_a, 1, &mut payment_id); },
+                       0x69 => { send_payment(&nodes[1], &nodes[0], chan_a, 1, &mut payment_id); },
+                       0x6a => { send_payment(&nodes[1], &nodes[2], chan_b, 1, &mut payment_id); },
+                       0x6b => { send_payment(&nodes[2], &nodes[1], chan_b, 1, &mut payment_id); },
+                       0x6c => { send_hop_payment(&nodes[0], &nodes[1], chan_a, &nodes[2], chan_b, 1, &mut payment_id); },
+                       0x6d => { send_hop_payment(&nodes[2], &nodes[1], chan_b, &nodes[0], chan_a, 1, &mut payment_id); },
+
+                       0x80 => {
+                               let max_feerate = last_htlc_clear_fee_a * FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE as u32;
+                               if fee_est_a.ret_val.fetch_add(250, atomic::Ordering::AcqRel) + 250 > max_feerate {
+                                       fee_est_a.ret_val.store(max_feerate, atomic::Ordering::Release);
+                               }
+                               nodes[0].maybe_update_chan_fees();
+                       },
+                       0x81 => { fee_est_a.ret_val.store(253, atomic::Ordering::Release); nodes[0].maybe_update_chan_fees(); },
+
+                       0x84 => {
+                               let max_feerate = last_htlc_clear_fee_b * FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE as u32;
+                               if fee_est_b.ret_val.fetch_add(250, atomic::Ordering::AcqRel) + 250 > max_feerate {
+                                       fee_est_b.ret_val.store(max_feerate, atomic::Ordering::Release);
+                               }
+                               nodes[1].maybe_update_chan_fees();
+                       },
+                       0x85 => { fee_est_b.ret_val.store(253, atomic::Ordering::Release); nodes[1].maybe_update_chan_fees(); },
+
+                       0x88 => {
+                               let max_feerate = last_htlc_clear_fee_c * FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE as u32;
+                               if fee_est_c.ret_val.fetch_add(250, atomic::Ordering::AcqRel) + 250 > max_feerate {
+                                       fee_est_c.ret_val.store(max_feerate, atomic::Ordering::Release);
+                               }
+                               nodes[2].maybe_update_chan_fees();
+                       },
+                       0x89 => { fee_est_c.ret_val.store(253, atomic::Ordering::Release); nodes[2].maybe_update_chan_fees(); },
 
                        0xff => {
                                // Test that no channel is in a stuck state where neither party can send funds even
@@ -935,22 +1101,22 @@ pub fn do_test<Out: test_logger::Output>(data: &[u8], out: Out) {
 
                                // Next, make sure peers are all connected to each other
                                if chan_a_disconnected {
-                                       nodes[0].peer_connected(&nodes[1].get_our_node_id(), &Init { features: InitFeatures::empty() });
-                                       nodes[1].peer_connected(&nodes[0].get_our_node_id(), &Init { features: InitFeatures::empty() });
+                                       nodes[0].peer_connected(&nodes[1].get_our_node_id(), &Init { features: InitFeatures::known() });
+                                       nodes[1].peer_connected(&nodes[0].get_our_node_id(), &Init { features: InitFeatures::known() });
                                        chan_a_disconnected = false;
                                }
                                if chan_b_disconnected {
-                                       nodes[1].peer_connected(&nodes[2].get_our_node_id(), &Init { features: InitFeatures::empty() });
-                                       nodes[2].peer_connected(&nodes[1].get_our_node_id(), &Init { features: InitFeatures::empty() });
+                                       nodes[1].peer_connected(&nodes[2].get_our_node_id(), &Init { features: InitFeatures::known() });
+                                       nodes[2].peer_connected(&nodes[1].get_our_node_id(), &Init { features: InitFeatures::known() });
                                        chan_b_disconnected = false;
                                }
 
                                for i in 0..std::usize::MAX {
                                        if i == 100 { panic!("It may take may iterations to settle the state, but it should not take forever"); }
                                        // Then, make sure any current forwards make their way to their destination
-                                       if process_msg_events!(0, false) { continue; }
-                                       if process_msg_events!(1, false) { continue; }
-                                       if process_msg_events!(2, false) { continue; }
+                                       if process_msg_events!(0, false, ProcessMessages::AllMessages) { continue; }
+                                       if process_msg_events!(1, false, ProcessMessages::AllMessages) { continue; }
+                                       if process_msg_events!(2, false, ProcessMessages::AllMessages) { continue; }
                                        // ...making sure any pending PendingHTLCsForwardable events are handled and
                                        // payments claimed.
                                        if process_events!(0, false) { continue; }
@@ -966,6 +1132,10 @@ pub fn do_test<Out: test_logger::Output>(data: &[u8], out: Out) {
                                assert!(
                                        send_payment(&nodes[1], &nodes[2], chan_b, 10_000_000, &mut payment_id) ||
                                        send_payment(&nodes[2], &nodes[1], chan_b, 10_000_000, &mut payment_id));
+
+                               last_htlc_clear_fee_a = fee_est_a.ret_val.load(atomic::Ordering::Acquire);
+                               last_htlc_clear_fee_b = fee_est_b.ret_val.load(atomic::Ordering::Acquire);
+                               last_htlc_clear_fee_c = fee_est_c.ret_val.load(atomic::Ordering::Acquire);
                        },
                        _ => test_return!(),
                }