chanmon_consistency.rs

// This file is Copyright its original authors, visible in version control
// history.
//
// This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
// or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
// You may not use this file except in accordance with one or both of these
// licenses.

//! Test that monitor update failures don't get our channel state out of sync.
//! One of the biggest concern with the monitor update failure handling code is that messages
//! resent after monitor updating is restored are delivered out-of-order, resulting in
//! commitment_signed messages having "invalid signatures".
//! To test this we stand up a network of three nodes and read bytes from the fuzz input to denote
//! actions such as sending payments, handling events, or changing monitor update return values on
//! a per-node basis. This should allow it to find any cases where the ordering of actions results
//! in us getting out of sync with ourselves, and, assuming at least one of our recieve- or
//! send-side handling is correct, other peers. We consider it a failure if any action results in a
//! channel being force-closed.

use bitcoin::amount::Amount;
use bitcoin::constants::genesis_block;
use bitcoin::locktime::absolute::LockTime;
use bitcoin::network::Network;
use bitcoin::opcodes;
use bitcoin::script::{Builder, ScriptBuf};
use bitcoin::transaction::Version;
use bitcoin::transaction::{Transaction, TxOut};

use bitcoin::hash_types::BlockHash;
use bitcoin::hashes::sha256::Hash as Sha256;
use bitcoin::hashes::sha256d::Hash as Sha256dHash;
use bitcoin::hashes::Hash as TraitImport;
use bitcoin::WPubkeyHash;

use lightning::blinded_path::message::{BlindedMessagePath, MessageContext};
use lightning::blinded_path::payment::{BlindedPaymentPath, ReceiveTlvs};
use lightning::chain;
use lightning::chain::chaininterface::{BroadcasterInterface, ConfirmationTarget, FeeEstimator};
use lightning::chain::channelmonitor::{ChannelMonitor, MonitorEvent};
use lightning::chain::transaction::OutPoint;
use lightning::chain::{
	chainmonitor, channelmonitor, BestBlock, ChannelMonitorUpdateStatus, Confirm, Watch,
};
use lightning::events;
use lightning::ln::channel::FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE;
use lightning::ln::channel_state::ChannelDetails;
use lightning::ln::channelmanager::{
	ChainParameters, ChannelManager, ChannelManagerReadArgs, PaymentId, RecentPaymentDetails,
	RecipientOnionFields,
};
use lightning::ln::functional_test_utils::*;
use lightning::ln::inbound_payment::ExpandedKey;
use lightning::ln::msgs::{
	BaseMessageHandler, ChannelMessageHandler, CommitmentUpdate, Init, MessageSendEvent,
	UpdateAddHTLC,
};
use lightning::ln::script::ShutdownScript;
use lightning::ln::types::ChannelId;
use lightning::offers::invoice::UnsignedBolt12Invoice;
use lightning::onion_message::messenger::{Destination, MessageRouter, OnionMessagePath};
use lightning::routing::router::{
	InFlightHtlcs, Path, PaymentParameters, Route, RouteHop, RouteParameters, Router,
};
use lightning::sign::{EntropySource, InMemorySigner, NodeSigner, Recipient, SignerProvider};
use lightning::types::payment::{PaymentHash, PaymentPreimage, PaymentSecret};
use lightning::util::config::UserConfig;
use lightning::util::hash_tables::*;
use lightning::util::logger::Logger;
use lightning::util::ser::{LengthReadable, ReadableArgs, Writeable, Writer};
use lightning::util::test_channel_signer::{EnforcementState, TestChannelSigner};

use lightning_invoice::RawBolt11Invoice;

use crate::utils::test_logger::{self, Output};
use crate::utils::test_persister::TestPersister;

use bitcoin::secp256k1::ecdh::SharedSecret;
use bitcoin::secp256k1::ecdsa::{RecoverableSignature, Signature};
use bitcoin::secp256k1::schnorr;
use bitcoin::secp256k1::{self, Message, PublicKey, Scalar, Secp256k1, SecretKey};

use lightning::io::Cursor;
use lightning::util::dyn_signer::DynSigner;
use std::cmp::{self, Ordering};
use std::mem;
use std::sync::atomic;
use std::sync::{Arc, Mutex};

const MAX_FEE: u32 = 10_000;
struct FuzzEstimator {
	ret_val: atomic::AtomicU32,
}
impl FeeEstimator for FuzzEstimator {
	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::MaximumFeeEstimate | ConfirmationTarget::UrgentOnChainSweep => {
				MAX_FEE
			},
			ConfirmationTarget::ChannelCloseMinimum
			| ConfirmationTarget::AnchorChannelFee
			| ConfirmationTarget::MinAllowedAnchorChannelRemoteFee
			| ConfirmationTarget::MinAllowedNonAnchorChannelRemoteFee
			| ConfirmationTarget::OutputSpendingFee => 253,
			ConfirmationTarget::NonAnchorChannelFee => {
				cmp::min(self.ret_val.load(atomic::Ordering::Acquire), MAX_FEE)
			},
		}
	}
}

struct FuzzRouter {}

impl Router for FuzzRouter {
	fn find_route(
		&self, _payer: &PublicKey, _params: &RouteParameters,
		_first_hops: Option<&[&ChannelDetails]>, _inflight_htlcs: InFlightHtlcs,
	) -> Result<Route, &'static str> {
		unreachable!()
	}

	fn create_blinded_payment_paths<T: secp256k1::Signing + secp256k1::Verification>(
		&self, _recipient: PublicKey, _first_hops: Vec<ChannelDetails>, _tlvs: ReceiveTlvs,
		_amount_msats: Option<u64>, _secp_ctx: &Secp256k1<T>,
	) -> Result<Vec<BlindedPaymentPath>, ()> {
		unreachable!()
	}
}

impl MessageRouter for FuzzRouter {
	fn find_path(
		&self, _sender: PublicKey, _peers: Vec<PublicKey>, _destination: Destination,
	) -> Result<OnionMessagePath, ()> {
		unreachable!()
	}

	fn create_blinded_paths<T: secp256k1::Signing + secp256k1::Verification>(
		&self, _recipient: PublicKey, _context: MessageContext, _peers: Vec<PublicKey>,
		_secp_ctx: &Secp256k1<T>,
	) -> Result<Vec<BlindedMessagePath>, ()> {
		unreachable!()
	}
}

pub struct TestBroadcaster {}
impl BroadcasterInterface for TestBroadcaster {
	fn broadcast_transactions(&self, _txs: &[&Transaction]) {}
}

pub struct VecWriter(pub Vec<u8>);
impl Writer for VecWriter {
	fn write_all(&mut self, buf: &[u8]) -> Result<(), ::lightning::io::Error> {
		self.0.extend_from_slice(buf);
		Ok(())
	}
}

/// The LDK API requires that any time we tell it we're done persisting a `ChannelMonitor[Update]`
/// we never pass it in as the "latest" `ChannelMonitor` on startup. However, we can pass
/// out-of-date monitors as long as we never told LDK we finished persisting them, which we do by
/// storing both old `ChannelMonitor`s and ones that are "being persisted" here.
///
/// Note that such "being persisted" `ChannelMonitor`s are stored in `ChannelManager` and will
/// simply be replayed on startup.
struct LatestMonitorState {
	/// The latest monitor id which we told LDK we've persisted
	persisted_monitor_id: u64,
	/// The latest serialized `ChannelMonitor` that we told LDK we persisted.
	persisted_monitor: Vec<u8>,
	/// A set of (monitor id, serialized `ChannelMonitor`)s which we're currently "persisting",
	/// from LDK's perspective.
	pending_monitors: Vec<(u64, Vec<u8>)>,
}

struct TestChainMonitor {
	pub logger: Arc<dyn Logger>,
	pub keys: Arc<KeyProvider>,
	pub persister: Arc<TestPersister>,
	pub chain_monitor: Arc<
		chainmonitor::ChainMonitor<
			TestChannelSigner,
			Arc<dyn chain::Filter>,
			Arc<TestBroadcaster>,
			Arc<FuzzEstimator>,
			Arc<dyn Logger>,
			Arc<TestPersister>,
		>,
	>,
	pub latest_monitors: Mutex<HashMap<ChannelId, LatestMonitorState>>,
}
impl TestChainMonitor {
	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,
				Arc::clone(&persister),
			)),
			logger,
			keys,
			persister,
			latest_monitors: Mutex::new(new_hash_map()),
		}
	}
}
impl chain::Watch<TestChannelSigner> for TestChainMonitor {
	fn watch_channel(
		&self, channel_id: ChannelId, monitor: channelmonitor::ChannelMonitor<TestChannelSigner>,
	) -> Result<chain::ChannelMonitorUpdateStatus, ()> {
		let mut ser = VecWriter(Vec::new());
		monitor.write(&mut ser).unwrap();
		let monitor_id = monitor.get_latest_update_id();
		let res = self.chain_monitor.watch_channel(channel_id, monitor);
		let state = match res {
			Ok(chain::ChannelMonitorUpdateStatus::Completed) => LatestMonitorState {
				persisted_monitor_id: monitor_id,
				persisted_monitor: ser.0,
				pending_monitors: Vec::new(),
			},
			Ok(chain::ChannelMonitorUpdateStatus::InProgress) => {
				panic!("The test currently doesn't test initial-persistence via the async pipeline")
			},
			Ok(chain::ChannelMonitorUpdateStatus::UnrecoverableError) => panic!(),
			Err(()) => panic!(),
		};
		if self.latest_monitors.lock().unwrap().insert(channel_id, state).is_some() {
			panic!("Already had monitor pre-watch_channel");
		}
		res
	}

	fn update_channel(
		&self, channel_id: ChannelId, update: &channelmonitor::ChannelMonitorUpdate,
	) -> chain::ChannelMonitorUpdateStatus {
		let mut map_lock = self.latest_monitors.lock().unwrap();
		let map_entry = map_lock.get_mut(&channel_id).expect("Didn't have monitor on update call");
		let latest_monitor_data = map_entry
			.pending_monitors
			.last()
			.as_ref()
			.map(|(_, data)| data)
			.unwrap_or(&map_entry.persisted_monitor);
		let deserialized_monitor =
			<(BlockHash, channelmonitor::ChannelMonitor<TestChannelSigner>)>::read(
				&mut Cursor::new(&latest_monitor_data),
				(&*self.keys, &*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();
		let res = self.chain_monitor.update_channel(channel_id, update);
		match res {
			chain::ChannelMonitorUpdateStatus::Completed => {
				map_entry.persisted_monitor_id = update.update_id;
				map_entry.persisted_monitor = ser.0;
			},
			chain::ChannelMonitorUpdateStatus::InProgress => {
				map_entry.pending_monitors.push((update.update_id, ser.0));
			},
			chain::ChannelMonitorUpdateStatus::UnrecoverableError => panic!(),
		}
		res
	}

	fn release_pending_monitor_events(
		&self,
	) -> Vec<(OutPoint, ChannelId, Vec<MonitorEvent>, PublicKey)> {
		return self.chain_monitor.release_pending_monitor_events();
	}
}

struct KeyProvider {
	node_secret: SecretKey,
	rand_bytes_id: atomic::AtomicU32,
	enforcement_states: Mutex<HashMap<[u8; 32], Arc<Mutex<EnforcementState>>>>,
}

impl EntropySource for KeyProvider {
	fn get_secure_random_bytes(&self) -> [u8; 32] {
		let id = self.rand_bytes_id.fetch_add(1, atomic::Ordering::Relaxed);
		#[rustfmt::skip]
		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_secret[31]];
		res[30 - 4..30].copy_from_slice(&id.to_le_bytes());
		res
	}
}

impl NodeSigner for KeyProvider {
	fn get_node_id(&self, recipient: Recipient) -> Result<PublicKey, ()> {
		let node_secret = match recipient {
			Recipient::Node => Ok(&self.node_secret),
			Recipient::PhantomNode => Err(()),
		}?;
		Ok(PublicKey::from_secret_key(&Secp256k1::signing_only(), node_secret))
	}

	fn ecdh(
		&self, recipient: Recipient, other_key: &PublicKey, tweak: Option<&Scalar>,
	) -> Result<SharedSecret, ()> {
		let mut node_secret = match recipient {
			Recipient::Node => Ok(self.node_secret.clone()),
			Recipient::PhantomNode => Err(()),
		}?;
		if let Some(tweak) = tweak {
			node_secret = node_secret.mul_tweak(tweak).map_err(|_| ())?;
		}
		Ok(SharedSecret::new(other_key, &node_secret))
	}

	fn get_inbound_payment_key(&self) -> ExpandedKey {
		#[rustfmt::skip]
		let random_bytes = [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, 1, self.node_secret[31]];
		ExpandedKey::new(random_bytes)
	}

	fn sign_invoice(
		&self, _invoice: &RawBolt11Invoice, _recipient: Recipient,
	) -> Result<RecoverableSignature, ()> {
		unreachable!()
	}

	fn sign_bolt12_invoice(
		&self, _invoice: &UnsignedBolt12Invoice,
	) -> Result<schnorr::Signature, ()> {
		unreachable!()
	}

	fn sign_gossip_message(
		&self, msg: lightning::ln::msgs::UnsignedGossipMessage,
	) -> Result<Signature, ()> {
		let msg_hash = Message::from_digest(Sha256dHash::hash(&msg.encode()[..]).to_byte_array());
		let secp_ctx = Secp256k1::signing_only();
		Ok(secp_ctx.sign_ecdsa(&msg_hash, &self.node_secret))
	}
}

impl SignerProvider for KeyProvider {
	type EcdsaSigner = TestChannelSigner;
	#[cfg(taproot)]
	type TaprootSigner = TestChannelSigner;

	fn generate_channel_keys_id(&self, _inbound: bool, _user_channel_id: u128) -> [u8; 32] {
		let id = self.rand_bytes_id.fetch_add(1, atomic::Ordering::Relaxed) as u8;
		[id; 32]
	}

	fn derive_channel_signer(&self, channel_keys_id: [u8; 32]) -> Self::EcdsaSigner {
		let secp_ctx = Secp256k1::signing_only();
		let id = channel_keys_id[0];
		#[rustfmt::skip]
		let keys = InMemorySigner::new(
			&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, 4, self.node_secret[31]]).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, 5, self.node_secret[31]]).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, 6, self.node_secret[31]]).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_secret[31]]).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_secret[31]]).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_secret[31]],
			channel_keys_id,
			channel_keys_id,
		);
		let revoked_commitment = self.make_enforcement_state_cell(keys.commitment_seed);
		let keys = DynSigner::new(keys);
		TestChannelSigner::new_with_revoked(keys, revoked_commitment, false)
	}

	fn get_destination_script(&self, _channel_keys_id: [u8; 32]) -> Result<ScriptBuf, ()> {
		let secp_ctx = Secp256k1::signing_only();
		#[rustfmt::skip]
		let channel_monitor_claim_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, 2, self.node_secret[31]]).unwrap();
		let our_channel_monitor_claim_key_hash = WPubkeyHash::hash(
			&PublicKey::from_secret_key(&secp_ctx, &channel_monitor_claim_key).serialize(),
		);
		Ok(Builder::new()
			.push_opcode(opcodes::all::OP_PUSHBYTES_0)
			.push_slice(our_channel_monitor_claim_key_hash)
			.into_script())
	}

	fn get_shutdown_scriptpubkey(&self) -> Result<ShutdownScript, ()> {
		let secp_ctx = Secp256k1::signing_only();
		#[rustfmt::skip]
		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_secret[31]]).unwrap();
		let pubkey_hash =
			WPubkeyHash::hash(&PublicKey::from_secret_key(&secp_ctx, &secret_key).serialize());
		Ok(ShutdownScript::new_p2wpkh(&pubkey_hash))
	}
}

impl KeyProvider {
	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(EnforcementState::new())));
		}
		let cell = revoked_commitments.get(&commitment_seed).unwrap();
		Arc::clone(cell)
	}
}

// Returns a bool indicating whether the payment failed.
#[inline]
fn check_payment_send_events(source: &ChanMan, sent_payment_id: PaymentId) -> bool {
	for payment in source.list_recent_payments() {
		match payment {
			RecentPaymentDetails::Pending { payment_id, .. } if payment_id == sent_payment_id => {
				return true;
			},
			RecentPaymentDetails::Abandoned { payment_id, .. } if payment_id == sent_payment_id => {
				return false;
			},
			_ => {},
		}
	}
	return false;
}

type ChanMan<'a> = ChannelManager<
	Arc<TestChainMonitor>,
	Arc<TestBroadcaster>,
	Arc<KeyProvider>,
	Arc<KeyProvider>,
	Arc<KeyProvider>,
	Arc<FuzzEstimator>,
	&'a FuzzRouter,
	&'a FuzzRouter,
	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]).to_byte_array());
		if let Ok(payment_secret) =
			dest.create_inbound_payment_for_hash(payment_hash, None, 3600, None)
		{
			return Some((payment_secret, payment_hash));
		}
		*payment_id = payment_id.wrapping_add(1);
	}
	None
}

#[inline]
fn send_noret(
	source: &ChanMan, dest: &ChanMan, dest_chan_id: u64, amt: u64, payment_id: &mut u8,
	payment_idx: &mut u64,
) {
	send_payment(source, dest, dest_chan_id, amt, payment_id, payment_idx);
}

#[inline]
fn send_payment(
	source: &ChanMan, dest: &ChanMan, dest_chan_id: u64, amt: u64, payment_id: &mut u8,
	payment_idx: &mut u64,
) -> bool {
	let (payment_secret, payment_hash) =
		if let Some((secret, hash)) = get_payment_secret_hash(dest, payment_id) {
			(secret, hash)
		} else {
			return true;
		};
	let mut payment_id = [0; 32];
	payment_id[0..8].copy_from_slice(&payment_idx.to_ne_bytes());
	*payment_idx += 1;
	let (min_value_sendable, max_value_sendable) = source
		.list_usable_channels()
		.iter()
		.find(|chan| chan.short_channel_id == Some(dest_chan_id))
		.map(|chan| (chan.next_outbound_htlc_minimum_msat, chan.next_outbound_htlc_limit_msat))
		.unwrap_or((0, 0));
	let route_params = RouteParameters::from_payment_params_and_value(
		PaymentParameters::from_node_id(source.get_our_node_id(), TEST_FINAL_CLTV),
		amt,
	);
	let route = Route {
		paths: vec![Path {
			hops: vec![RouteHop {
				pubkey: dest.get_our_node_id(),
				node_features: dest.node_features(),
				short_channel_id: dest_chan_id,
				channel_features: dest.channel_features(),
				fee_msat: amt,
				cltv_expiry_delta: 200,
				maybe_announced_channel: true,
			}],
			blinded_tail: None,
		}],
		route_params: Some(route_params.clone()),
	};
	let onion = RecipientOnionFields::secret_only(payment_secret);
	let payment_id = PaymentId(payment_id);
	let res = source.send_payment_with_route(route, payment_hash, onion, payment_id);
	match res {
		Err(err) => {
			panic!("Errored with {:?} on initial payment send", err);
		},
		Ok(()) => {
			let expect_failure = amt < min_value_sendable || amt > max_value_sendable;
			let succeeded = check_payment_send_events(source, payment_id);
			assert_eq!(succeeded, !expect_failure);
			succeeded
		},
	}
}

#[inline]
fn send_hop_noret(
	source: &ChanMan, middle: &ChanMan, middle_chan_id: u64, dest: &ChanMan, dest_chan_id: u64,
	amt: u64, payment_id: &mut u8, payment_idx: &mut u64,
) {
	send_hop_payment(
		source,
		middle,
		middle_chan_id,
		dest,
		dest_chan_id,
		amt,
		payment_id,
		payment_idx,
	);
}

#[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, payment_idx: &mut u64,
) -> bool {
	let (payment_secret, payment_hash) =
		if let Some((secret, hash)) = get_payment_secret_hash(dest, payment_id) {
			(secret, hash)
		} else {
			return true;
		};
	let mut payment_id = [0; 32];
	payment_id[0..8].copy_from_slice(&payment_idx.to_ne_bytes());
	*payment_idx += 1;
	let (min_value_sendable, max_value_sendable) = source
		.list_usable_channels()
		.iter()
		.find(|chan| chan.short_channel_id == Some(middle_chan_id))
		.map(|chan| (chan.next_outbound_htlc_minimum_msat, chan.next_outbound_htlc_limit_msat))
		.unwrap_or((0, 0));
	let first_hop_fee = 50_000;
	let route_params = RouteParameters::from_payment_params_and_value(
		PaymentParameters::from_node_id(source.get_our_node_id(), TEST_FINAL_CLTV),
		amt,
	);
	let route = Route {
		paths: vec![Path {
			hops: vec![
				RouteHop {
					pubkey: middle.get_our_node_id(),
					node_features: middle.node_features(),
					short_channel_id: middle_chan_id,
					channel_features: middle.channel_features(),
					fee_msat: first_hop_fee,
					cltv_expiry_delta: 100,
					maybe_announced_channel: true,
				},
				RouteHop {
					pubkey: dest.get_our_node_id(),
					node_features: dest.node_features(),
					short_channel_id: dest_chan_id,
					channel_features: dest.channel_features(),
					fee_msat: amt,
					cltv_expiry_delta: 200,
					maybe_announced_channel: true,
				},
			],
			blinded_tail: None,
		}],
		route_params: Some(route_params.clone()),
	};
	let onion = RecipientOnionFields::secret_only(payment_secret);
	let payment_id = PaymentId(payment_id);
	let res = source.send_payment_with_route(route, payment_hash, onion, payment_id);
	match res {
		Err(err) => {
			panic!("Errored with {:?} on initial payment send", err);
		},
		Ok(()) => {
			let sent_amt = amt + first_hop_fee;
			let expect_failure = sent_amt < min_value_sendable || sent_amt > max_value_sendable;
			let succeeded = check_payment_send_events(source, payment_id);
			assert_eq!(succeeded, !expect_failure);
			succeeded
		},
	}
}

#[inline]
pub fn do_test<Out: Output>(data: &[u8], underlying_out: Out, anchors: bool) {
	let out = SearchingOutput::new(underlying_out);
	let broadcast = Arc::new(TestBroadcaster {});
	let router = FuzzRouter {};

	macro_rules! make_node {
		($node_id: expr, $fee_estimator: expr) => {{
			let logger: Arc<dyn Logger> =
				Arc::new(test_logger::TestLogger::new($node_id.to_string(), out.clone()));
			let node_secret = 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, 1, $node_id,
			])
			.unwrap();
			let keys_manager = Arc::new(KeyProvider {
				node_secret,
				rand_bytes_id: atomic::AtomicU32::new(0),
				enforcement_states: Mutex::new(new_hash_map()),
			});
			let monitor = Arc::new(TestChainMonitor::new(
				broadcast.clone(),
				logger.clone(),
				$fee_estimator.clone(),
				Arc::new(TestPersister {
					update_ret: Mutex::new(ChannelMonitorUpdateStatus::Completed),
				}),
				Arc::clone(&keys_manager),
			));

			let mut config = UserConfig::default();
			config.channel_config.forwarding_fee_proportional_millionths = 0;
			config.channel_handshake_config.announce_for_forwarding = true;
			if anchors {
				config.channel_handshake_config.negotiate_anchors_zero_fee_htlc_tx = true;
				config.manually_accept_inbound_channels = true;
			}
			let network = Network::Bitcoin;
			let best_block_timestamp = genesis_block(network).header.time;
			let params = ChainParameters { network, best_block: BestBlock::from_network(network) };
			(
				ChannelManager::new(
					$fee_estimator.clone(),
					monitor.clone(),
					broadcast.clone(),
					&router,
					&router,
					Arc::clone(&logger),
					keys_manager.clone(),
					keys_manager.clone(),
					keys_manager.clone(),
					config,
					params,
					best_block_timestamp,
				),
				monitor,
				keys_manager,
			)
		}};
	}

	macro_rules! reload_node {
		($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(),
				$fee_estimator.clone(),
				Arc::new(TestPersister {
					update_ret: Mutex::new(ChannelMonitorUpdateStatus::Completed),
				}),
				Arc::clone(&$keys_manager),
			));

			let mut config = UserConfig::default();
			config.channel_config.forwarding_fee_proportional_millionths = 0;
			config.channel_handshake_config.announce_for_forwarding = true;
			if anchors {
				config.channel_handshake_config.negotiate_anchors_zero_fee_htlc_tx = true;
				config.manually_accept_inbound_channels = true;
			}

			let mut monitors = new_hash_map();
			let mut old_monitors = $old_monitors.latest_monitors.lock().unwrap();
			for (channel_id, mut prev_state) in old_monitors.drain() {
				monitors.insert(
					channel_id,
					<(BlockHash, ChannelMonitor<TestChannelSigner>)>::read(
						&mut Cursor::new(&prev_state.persisted_monitor),
						(&*$keys_manager, &*$keys_manager),
					)
					.expect("Failed to read monitor")
					.1,
				);
				// Wipe any `ChannelMonitor`s which we never told LDK we finished persisting,
				// considering them discarded. LDK should replay these for us as they're stored in
				// the `ChannelManager`.
				prev_state.pending_monitors.clear();
				chain_monitor.latest_monitors.lock().unwrap().insert(channel_id, prev_state);
			}
			let mut monitor_refs = new_hash_map();
			for (channel_id, monitor) in monitors.iter() {
				monitor_refs.insert(*channel_id, monitor);
			}

			let read_args = ChannelManagerReadArgs {
				entropy_source: keys_manager.clone(),
				node_signer: keys_manager.clone(),
				signer_provider: keys_manager.clone(),
				fee_estimator: $fee_estimator.clone(),
				chain_monitor: chain_monitor.clone(),
				tx_broadcaster: broadcast.clone(),
				router: &router,
				message_router: &router,
				logger,
				default_config: config,
				channel_monitors: monitor_refs,
			};

			let res = (
				<(BlockHash, ChanMan)>::read(&mut Cursor::new(&$ser.0), read_args)
					.expect("Failed to read manager")
					.1,
				chain_monitor.clone(),
			);
			for (channel_id, mon) in monitors.drain() {
				assert_eq!(
					chain_monitor.chain_monitor.watch_channel(channel_id, mon),
					Ok(ChannelMonitorUpdateStatus::Completed)
				);
			}
			res
		}};
	}

	let mut channel_txn = Vec::new();
	macro_rules! make_channel {
		($source: expr, $dest: expr, $dest_keys_manager: expr, $chan_id: expr) => {{
			let init_dest = Init {
				features: $dest.init_features(),
				networks: None,
				remote_network_address: None,
			};
			$source.peer_connected($dest.get_our_node_id(), &init_dest, true).unwrap();
			let init_src = Init {
				features: $source.init_features(),
				networks: None,
				remote_network_address: None,
			};
			$dest.peer_connected($source.get_our_node_id(), &init_src, false).unwrap();

			$source.create_channel($dest.get_our_node_id(), 100_000, 42, 0, None, None).unwrap();
			let open_channel = {
				let events = $source.get_and_clear_pending_msg_events();
				assert_eq!(events.len(), 1);
				if let MessageSendEvent::SendOpenChannel { ref msg, .. } = events[0] {
					msg.clone()
				} else {
					panic!("Wrong event type");
				}
			};

			$dest.handle_open_channel($source.get_our_node_id(), &open_channel);
			let accept_channel = {
				if anchors {
					let events = $dest.get_and_clear_pending_events();
					assert_eq!(events.len(), 1);
					if let events::Event::OpenChannelRequest {
						ref temporary_channel_id,
						ref counterparty_node_id,
						..
					} = events[0]
					{
						let mut random_bytes = [0u8; 16];
						random_bytes
							.copy_from_slice(&$dest_keys_manager.get_secure_random_bytes()[..16]);
						let user_channel_id = u128::from_be_bytes(random_bytes);
						$dest
							.accept_inbound_channel(
								temporary_channel_id,
								counterparty_node_id,
								user_channel_id,
								None,
							)
							.unwrap();
					} else {
						panic!("Wrong event type");
					}
				}
				let events = $dest.get_and_clear_pending_msg_events();
				assert_eq!(events.len(), 1);
				if let MessageSendEvent::SendAcceptChannel { ref msg, .. } = events[0] {
					msg.clone()
				} else {
					panic!("Wrong event type");
				}
			};

			$source.handle_accept_channel($dest.get_our_node_id(), &accept_channel);
			{
				let mut events = $source.get_and_clear_pending_events();
				assert_eq!(events.len(), 1);
				if let events::Event::FundingGenerationReady {
					temporary_channel_id,
					channel_value_satoshis,
					output_script,
					..
				} = events.pop().unwrap()
				{
					let tx = Transaction {
						version: Version($chan_id),
						lock_time: LockTime::ZERO,
						input: Vec::new(),
						output: vec![TxOut {
							value: Amount::from_sat(channel_value_satoshis),
							script_pubkey: output_script,
						}],
					};
					$source
						.funding_transaction_generated(
							temporary_channel_id,
							$dest.get_our_node_id(),
							tx.clone(),
						)
						.unwrap();
					channel_txn.push(tx);
				} else {
					panic!("Wrong event type");
				}
			}

			let funding_created = {
				let events = $source.get_and_clear_pending_msg_events();
				assert_eq!(events.len(), 1);
				if let MessageSendEvent::SendFundingCreated { ref msg, .. } = events[0] {
					msg.clone()
				} else {
					panic!("Wrong event type");
				}
			};
			$dest.handle_funding_created($source.get_our_node_id(), &funding_created);

			let funding_signed = {
				let events = $dest.get_and_clear_pending_msg_events();
				assert_eq!(events.len(), 1);
				if let MessageSendEvent::SendFundingSigned { ref msg, .. } = events[0] {
					msg.clone()
				} else {
					panic!("Wrong event type");
				}
			};
			let events = $dest.get_and_clear_pending_events();
			assert_eq!(events.len(), 1);
			if let events::Event::ChannelPending { ref counterparty_node_id, .. } = events[0] {
				assert_eq!(counterparty_node_id, &$source.get_our_node_id());
			} else {
				panic!("Wrong event type");
			}

			$source.handle_funding_signed($dest.get_our_node_id(), &funding_signed);
			let events = $source.get_and_clear_pending_events();
			assert_eq!(events.len(), 1);
			let channel_id = if let events::Event::ChannelPending {
				ref counterparty_node_id,
				ref channel_id,
				..
			} = events[0]
			{
				assert_eq!(counterparty_node_id, &$dest.get_our_node_id());
				channel_id.clone()
			} else {
				panic!("Wrong event type");
			};

			channel_id
		}};
	}

	macro_rules! confirm_txn {
		($node: expr) => {{
			let chain_hash = genesis_block(Network::Bitcoin).block_hash();
			let mut header = create_dummy_header(chain_hash, 42);
			let txdata: Vec<_> =
				channel_txn.iter().enumerate().map(|(i, tx)| (i + 1, tx)).collect();
			$node.transactions_confirmed(&header, &txdata, 1);
			for _ in 2..100 {
				header = create_dummy_header(header.block_hash(), 42);
			}
			$node.best_block_updated(&header, 99);
		}};
	}

	macro_rules! lock_fundings {
		($nodes: expr) => {{
			let mut node_events = Vec::new();
			for node in $nodes.iter() {
				node_events.push(node.get_and_clear_pending_msg_events());
			}
			for (idx, node_event) in node_events.iter().enumerate() {
				for event in node_event {
					if let MessageSendEvent::SendChannelReady { ref node_id, ref msg } = event {
						for node in $nodes.iter() {
							if node.get_our_node_id() == *node_id {
								node.handle_channel_ready($nodes[idx].get_our_node_id(), msg);
							}
						}
					} else {
						panic!("Wrong event type");
					}
				}
			}

			for node in $nodes.iter() {
				let events = node.get_and_clear_pending_msg_events();
				for event in events {
					if let MessageSendEvent::SendAnnouncementSignatures { .. } = event {
					} else {
						panic!("Wrong event type");
					}
				}
			}
		}};
	}

	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, 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];

	let chan_1_id = make_channel!(nodes[0], nodes[1], keys_manager_b, 0);
	let chan_2_id = make_channel!(nodes[1], nodes[2], keys_manager_c, 1);

	for node in nodes.iter() {
		confirm_txn!(node);
	}

	lock_fundings!(nodes);

	let chan_a = nodes[0].list_usable_channels()[0].short_channel_id.unwrap();
	let chan_a_id = nodes[0].list_usable_channels()[0].channel_id;
	let chan_b = nodes[2].list_usable_channels()[0].short_channel_id.unwrap();
	let chan_b_id = nodes[2].list_usable_channels()[0].channel_id;

	let mut p_id: u8 = 0;
	let mut p_idx: u64 = 0;

	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();
	let mut node_b_ser = VecWriter(Vec::new());
	nodes[1].write(&mut node_b_ser).unwrap();
	let mut node_c_ser = VecWriter(Vec::new());
	nodes[2].write(&mut node_c_ser).unwrap();

	macro_rules! test_return {
		() => {{
			assert_eq!(nodes[0].list_channels().len(), 1);
			assert_eq!(nodes[1].list_channels().len(), 2);
			assert_eq!(nodes[2].list_channels().len(), 1);
			return;
		}};
	}

	let mut read_pos = 0;
	macro_rules! get_slice {
		($len: expr) => {{
			let slice_len = $len as usize;
			if data.len() < read_pos + slice_len {
				test_return!();
			}
			read_pos += slice_len;
			&data[read_pos - slice_len..read_pos]
		}};
	}

	loop {
		// 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 {
						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
						},
						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
						},
						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
						},
						MessageSendEvent::SendStfu { 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
						},
						MessageSendEvent::SendChannelReady { .. } => continue,
						MessageSendEvent::SendAnnouncementSignatures { .. } => continue,
						MessageSendEvent::SendChannelUpdate { ref node_id, ref msg } => {
							assert_eq!(msg.contents.channel_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, $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 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;
				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 {
						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 from node {} to node {}.\n", $node, idx).as_bytes());
										if !$corrupt_forward {
											dest.handle_update_add_htlc(nodes[$node].get_our_node_id(), update_add);
										} else {
											// Corrupt the update_add_htlc message so that its HMAC
											// check will fail and we generate a
											// update_fail_malformed_htlc instead of an
											// update_fail_htlc as we do when we reject a payment.
											let mut msg_ser = update_add.encode();
											msg_ser[1000] ^= 0xff;
											let new_msg = UpdateAddHTLC::read_from_fixed_length_buffer(&mut &msg_ser[..]).unwrap();
											dest.handle_update_add_htlc(nodes[$node].get_our_node_id(), &new_msg);
										}
									}
									for update_fulfill in update_fulfill_htlcs.iter() {
										out.locked_write(format!("Delivering update_fulfill_htlc from node {} to node {}.\n", $node, idx).as_bytes());
										dest.handle_update_fulfill_htlc(nodes[$node].get_our_node_id(), update_fulfill);
									}
									for update_fail in update_fail_htlcs.iter() {
										out.locked_write(format!("Delivering update_fail_htlc from node {} to node {}.\n", $node, idx).as_bytes());
										dest.handle_update_fail_htlc(nodes[$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 from node {} to node {}.\n", $node, idx).as_bytes());
										dest.handle_update_fail_malformed_htlc(nodes[$node].get_our_node_id(), update_fail_malformed);
									}
									if let Some(msg) = update_fee {
										out.locked_write(format!("Delivering update_fee from node {} to node {}.\n", $node, idx).as_bytes());
										dest.handle_update_fee(nodes[$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(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 from node {} to node {}.\n", $node, idx).as_bytes());
									dest.handle_commitment_signed(nodes[$node].get_our_node_id(), &commitment_signed);
									break;
								}
							}
						},
						MessageSendEvent::SendRevokeAndACK { ref node_id, ref msg } => {
							for (idx, dest) in nodes.iter().enumerate() {
								if dest.get_our_node_id() == *node_id {
									out.locked_write(format!("Delivering revoke_and_ack from node {} to node {}.\n", $node, idx).as_bytes());
									dest.handle_revoke_and_ack(nodes[$node].get_our_node_id(), msg);
								}
							}
						},
						MessageSendEvent::SendChannelReestablish { ref node_id, ref msg } => {
							for (idx, dest) in nodes.iter().enumerate() {
								if dest.get_our_node_id() == *node_id {
									out.locked_write(format!("Delivering channel_reestablish from node {} to node {}.\n", $node, idx).as_bytes());
									dest.handle_channel_reestablish(nodes[$node].get_our_node_id(), msg);
								}
							}
						},
						MessageSendEvent::SendStfu { ref node_id, ref msg } => {
							for (idx, dest) in nodes.iter().enumerate() {
								if dest.get_our_node_id() == *node_id {
									out.locked_write(format!("Delivering stfu from node {} to node {}.\n", $node, idx).as_bytes());
									dest.handle_stfu(nodes[$node].get_our_node_id(), msg);
								}
							}
						}
						MessageSendEvent::SendChannelReady { .. } => {
							// Can be generated as a reestablish response
						},
						MessageSendEvent::SendAnnouncementSignatures { .. } => {
							// Can be generated as a reestablish response
						},
						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.channel_flags & 2, 0);
						},
						_ => if out.may_fail.load(atomic::Ordering::Acquire) {
							return;
						} else {
							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
			} }
		}

		macro_rules! process_msg_noret {
			($node: expr, $corrupt_forward: expr, $limit_events: expr) => {{
				process_msg_events!($node, $corrupt_forward, $limit_events);
			}};
		}

		macro_rules! drain_msg_events_on_disconnect {
			($counterparty_id: expr) => {{
				if $counterparty_id == 0 {
					for event in nodes[0].get_and_clear_pending_msg_events() {
						match event {
							MessageSendEvent::UpdateHTLCs { .. } => {},
							MessageSendEvent::SendRevokeAndACK { .. } => {},
							MessageSendEvent::SendChannelReestablish { .. } => {},
							MessageSendEvent::SendStfu { .. } => {},
							MessageSendEvent::SendChannelReady { .. } => {},
							MessageSendEvent::SendAnnouncementSignatures { .. } => {},
							MessageSendEvent::SendChannelUpdate { ref msg, .. } => {
								assert_eq!(msg.contents.channel_flags & 2, 0); // The disable bit must never be set!
							},
							_ => {
								if out.may_fail.load(atomic::Ordering::Acquire) {
									return;
								} else {
									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() {
						match event {
							MessageSendEvent::UpdateHTLCs { .. } => {},
							MessageSendEvent::SendRevokeAndACK { .. } => {},
							MessageSendEvent::SendChannelReestablish { .. } => {},
							MessageSendEvent::SendStfu { .. } => {},
							MessageSendEvent::SendChannelReady { .. } => {},
							MessageSendEvent::SendAnnouncementSignatures { .. } => {},
							MessageSendEvent::SendChannelUpdate { ref msg, .. } => {
								assert_eq!(msg.contents.channel_flags & 2, 0); // The disable bit must never be set!
							},
							_ => {
								if out.may_fail.load(atomic::Ordering::Acquire) {
									return;
								} else {
									panic!("Unhandled message event")
								}
							},
						}
					}
					push_excess_b_events!(
						nodes[1].get_and_clear_pending_msg_events().drain(..),
						Some(2)
					);
					bc_events.clear();
					cb_events.clear();
				}
			}};
		}

		macro_rules! process_events {
			($node: expr, $fail: expr) => {{
				// In case we get 256 payments we may have a hash collision, resulting in the
				// second claim/fail call not finding the duplicate-hash HTLC, so we have to
				// deduplicate the calls here.
				let mut claim_set = new_hash_map();
				let mut events = nodes[$node].get_and_clear_pending_events();
				// Sort events so that PendingHTLCsForwardable get processed last. This avoids a
				// case where we first process a PendingHTLCsForwardable, then claim/fail on a
				// PaymentClaimable, claiming/failing two HTLCs, but leaving a just-generated
				// PaymentClaimable event for the second HTLC in our pending_events (and breaking
				// our claim_set deduplication).
				events.sort_by(|a, b| {
					if let events::Event::PaymentClaimable { .. } = a {
						if let events::Event::PendingHTLCsForwardable { .. } = b {
							Ordering::Less
						} else {
							Ordering::Equal
						}
					} else if let events::Event::PendingHTLCsForwardable { .. } = a {
						if let events::Event::PaymentClaimable { .. } = b {
							Ordering::Greater
						} else {
							Ordering::Equal
						}
					} else {
						Ordering::Equal
					}
				});
				let had_events = !events.is_empty();
				for event in events.drain(..) {
					match event {
						events::Event::PaymentClaimable { payment_hash, .. } => {
							if claim_set.insert(payment_hash.0, ()).is_none() {
								if $fail {
									nodes[$node].fail_htlc_backwards(&payment_hash);
								} else {
									nodes[$node].claim_funds(PaymentPreimage(payment_hash.0));
								}
							}
						},
						events::Event::PaymentSent { .. } => {},
						events::Event::PaymentClaimed { .. } => {},
						events::Event::PaymentPathSuccessful { .. } => {},
						events::Event::PaymentPathFailed { .. } => {},
						events::Event::PaymentFailed { .. } => {},
						events::Event::ProbeSuccessful { .. }
						| events::Event::ProbeFailed { .. } => {
							// Even though we don't explicitly send probes, because probes are
							// detected based on hashing the payment hash+preimage, its rather
							// trivial for the fuzzer to build payments that accidentally end up
							// looking like probes.
						},
						events::Event::PaymentForwarded { .. } if $node == 1 => {},
						events::Event::ChannelReady { .. } => {},
						events::Event::PendingHTLCsForwardable { .. } => {
							nodes[$node].process_pending_htlc_forwards();
						},
						events::Event::HTLCHandlingFailed { .. } => {},
						_ => {
							if out.may_fail.load(atomic::Ordering::Acquire) {
								return;
							} else {
								panic!("Unhandled event")
							}
						},
					}
				}
				had_events
			}};
		}

		macro_rules! process_ev_noret {
			($node: expr, $fail: expr) => {{
				process_events!($node, $fail);
			}};
		}

		let complete_first = |v: &mut Vec<_>| if !v.is_empty() { Some(v.remove(0)) } else { None };
		let complete_second = |v: &mut Vec<_>| if v.len() > 1 { Some(v.remove(1)) } else { None };
		let complete_monitor_update =
			|monitor: &Arc<TestChainMonitor>,
			 chan_funding,
			 compl_selector: &dyn Fn(&mut Vec<(u64, Vec<u8>)>) -> Option<(u64, Vec<u8>)>| {
				if let Some(state) = monitor.latest_monitors.lock().unwrap().get_mut(chan_funding) {
					assert!(
						state.pending_monitors.windows(2).all(|pair| pair[0].0 < pair[1].0),
						"updates should be sorted by id"
					);
					if let Some((id, data)) = compl_selector(&mut state.pending_monitors) {
						monitor.chain_monitor.channel_monitor_updated(*chan_funding, id).unwrap();
						if id > state.persisted_monitor_id {
							state.persisted_monitor_id = id;
							state.persisted_monitor = data;
						}
					}
				}
			};

		let complete_all_monitor_updates = |monitor: &Arc<TestChainMonitor>, chan_id| {
			if let Some(state) = monitor.latest_monitors.lock().unwrap().get_mut(chan_id) {
				assert!(
					state.pending_monitors.windows(2).all(|pair| pair[0].0 < pair[1].0),
					"updates should be sorted by id"
				);
				for (id, data) in state.pending_monitors.drain(..) {
					monitor.chain_monitor.channel_monitor_updated(*chan_id, id).unwrap();
					if id > state.persisted_monitor_id {
						state.persisted_monitor_id = id;
						state.persisted_monitor = data;
					}
				}
			}
		};

		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.
			0x00 => {
				*monitor_a.persister.update_ret.lock().unwrap() =
					ChannelMonitorUpdateStatus::InProgress
			},
			0x01 => {
				*monitor_b.persister.update_ret.lock().unwrap() =
					ChannelMonitorUpdateStatus::InProgress
			},
			0x02 => {
				*monitor_c.persister.update_ret.lock().unwrap() =
					ChannelMonitorUpdateStatus::InProgress
			},
			0x04 => {
				*monitor_a.persister.update_ret.lock().unwrap() =
					ChannelMonitorUpdateStatus::Completed
			},
			0x05 => {
				*monitor_b.persister.update_ret.lock().unwrap() =
					ChannelMonitorUpdateStatus::Completed
			},
			0x06 => {
				*monitor_c.persister.update_ret.lock().unwrap() =
					ChannelMonitorUpdateStatus::Completed
			},

			0x08 => complete_all_monitor_updates(&monitor_a, &chan_1_id),
			0x09 => complete_all_monitor_updates(&monitor_b, &chan_1_id),
			0x0a => complete_all_monitor_updates(&monitor_b, &chan_2_id),
			0x0b => complete_all_monitor_updates(&monitor_c, &chan_2_id),

			0x0c => {
				if !chan_a_disconnected {
					nodes[0].peer_disconnected(nodes[1].get_our_node_id());
					nodes[1].peer_disconnected(nodes[0].get_our_node_id());
					chan_a_disconnected = true;
					drain_msg_events_on_disconnect!(0);
				}
			},
			0x0d => {
				if !chan_b_disconnected {
					nodes[1].peer_disconnected(nodes[2].get_our_node_id());
					nodes[2].peer_disconnected(nodes[1].get_our_node_id());
					chan_b_disconnected = true;
					drain_msg_events_on_disconnect!(2);
				}
			},
			0x0e => {
				if chan_a_disconnected {
					let init_1 = Init {
						features: nodes[1].init_features(),
						networks: None,
						remote_network_address: None,
					};
					nodes[0].peer_connected(nodes[1].get_our_node_id(), &init_1, true).unwrap();
					let init_0 = Init {
						features: nodes[0].init_features(),
						networks: None,
						remote_network_address: None,
					};
					nodes[1].peer_connected(nodes[0].get_our_node_id(), &init_0, false).unwrap();
					chan_a_disconnected = false;
				}
			},
			0x0f => {
				if chan_b_disconnected {
					let init_2 = Init {
						features: nodes[2].init_features(),
						networks: None,
						remote_network_address: None,
					};
					nodes[1].peer_connected(nodes[2].get_our_node_id(), &init_2, true).unwrap();
					let init_1 = Init {
						features: nodes[1].init_features(),
						networks: None,
						remote_network_address: None,
					};
					nodes[2].peer_connected(nodes[1].get_our_node_id(), &init_1, false).unwrap();
					chan_b_disconnected = false;
				}
			},

			0x10 => process_msg_noret!(0, true, ProcessMessages::AllMessages),
			0x11 => process_msg_noret!(0, false, ProcessMessages::AllMessages),
			0x12 => process_msg_noret!(0, true, ProcessMessages::OneMessage),
			0x13 => process_msg_noret!(0, false, ProcessMessages::OneMessage),
			0x14 => process_msg_noret!(0, true, ProcessMessages::OnePendingMessage),
			0x15 => process_msg_noret!(0, false, ProcessMessages::OnePendingMessage),

			0x16 => process_ev_noret!(0, true),
			0x17 => process_ev_noret!(0, false),

			0x18 => process_msg_noret!(1, true, ProcessMessages::AllMessages),
			0x19 => process_msg_noret!(1, false, ProcessMessages::AllMessages),
			0x1a => process_msg_noret!(1, true, ProcessMessages::OneMessage),
			0x1b => process_msg_noret!(1, false, ProcessMessages::OneMessage),
			0x1c => process_msg_noret!(1, true, ProcessMessages::OnePendingMessage),
			0x1d => process_msg_noret!(1, false, ProcessMessages::OnePendingMessage),

			0x1e => process_ev_noret!(1, true),
			0x1f => process_ev_noret!(1, false),

			0x20 => process_msg_noret!(2, true, ProcessMessages::AllMessages),
			0x21 => process_msg_noret!(2, false, ProcessMessages::AllMessages),
			0x22 => process_msg_noret!(2, true, ProcessMessages::OneMessage),
			0x23 => process_msg_noret!(2, false, ProcessMessages::OneMessage),
			0x24 => process_msg_noret!(2, true, ProcessMessages::OnePendingMessage),
			0x25 => process_msg_noret!(2, false, ProcessMessages::OnePendingMessage),

			0x26 => process_ev_noret!(2, true),
			0x27 => process_ev_noret!(2, false),

			0x2c => {
				if !chan_a_disconnected {
					nodes[1].peer_disconnected(nodes[0].get_our_node_id());
					chan_a_disconnected = true;
					push_excess_b_events!(
						nodes[1].get_and_clear_pending_msg_events().drain(..),
						Some(0)
					);
					ab_events.clear();
					ba_events.clear();
				}
				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;
			},
			0x2d => {
				if !chan_a_disconnected {
					nodes[0].peer_disconnected(nodes[1].get_our_node_id());
					chan_a_disconnected = true;
					nodes[0].get_and_clear_pending_msg_events();
					ab_events.clear();
					ba_events.clear();
				}
				if !chan_b_disconnected {
					nodes[2].peer_disconnected(nodes[1].get_our_node_id());
					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, fee_est_b);
				nodes[1] = new_node_b;
				monitor_b = new_monitor_b;
			},
			0x2e => {
				if !chan_b_disconnected {
					nodes[1].peer_disconnected(nodes[2].get_our_node_id());
					chan_b_disconnected = true;
					push_excess_b_events!(
						nodes[1].get_and_clear_pending_msg_events().drain(..),
						Some(2)
					);
					bc_events.clear();
					cb_events.clear();
				}
				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:
			0x30 => send_noret(&nodes[0], &nodes[1], chan_a, 10_000_000, &mut p_id, &mut p_idx),
			0x31 => send_noret(&nodes[1], &nodes[0], chan_a, 10_000_000, &mut p_id, &mut p_idx),
			0x32 => send_noret(&nodes[1], &nodes[2], chan_b, 10_000_000, &mut p_id, &mut p_idx),
			0x33 => send_noret(&nodes[2], &nodes[1], chan_b, 10_000_000, &mut p_id, &mut p_idx),
			0x34 => send_hop_noret(
				&nodes[0], &nodes[1], chan_a, &nodes[2], chan_b, 10_000_000, &mut p_id, &mut p_idx,
			),
			0x35 => send_hop_noret(
				&nodes[2], &nodes[1], chan_b, &nodes[0], chan_a, 10_000_000, &mut p_id, &mut p_idx,
			),

			0x38 => send_noret(&nodes[0], &nodes[1], chan_a, 1_000_000, &mut p_id, &mut p_idx),
			0x39 => send_noret(&nodes[1], &nodes[0], chan_a, 1_000_000, &mut p_id, &mut p_idx),
			0x3a => send_noret(&nodes[1], &nodes[2], chan_b, 1_000_000, &mut p_id, &mut p_idx),
			0x3b => send_noret(&nodes[2], &nodes[1], chan_b, 1_000_000, &mut p_id, &mut p_idx),
			0x3c => send_hop_noret(
				&nodes[0], &nodes[1], chan_a, &nodes[2], chan_b, 1_000_000, &mut p_id, &mut p_idx,
			),
			0x3d => send_hop_noret(
				&nodes[2], &nodes[1], chan_b, &nodes[0], chan_a, 1_000_000, &mut p_id, &mut p_idx,
			),

			0x40 => send_noret(&nodes[0], &nodes[1], chan_a, 100_000, &mut p_id, &mut p_idx),
			0x41 => send_noret(&nodes[1], &nodes[0], chan_a, 100_000, &mut p_id, &mut p_idx),
			0x42 => send_noret(&nodes[1], &nodes[2], chan_b, 100_000, &mut p_id, &mut p_idx),
			0x43 => send_noret(&nodes[2], &nodes[1], chan_b, 100_000, &mut p_id, &mut p_idx),
			0x44 => send_hop_noret(
				&nodes[0], &nodes[1], chan_a, &nodes[2], chan_b, 100_000, &mut p_id, &mut p_idx,
			),
			0x45 => send_hop_noret(
				&nodes[2], &nodes[1], chan_b, &nodes[0], chan_a, 100_000, &mut p_id, &mut p_idx,
			),

			0x48 => send_noret(&nodes[0], &nodes[1], chan_a, 10_000, &mut p_id, &mut p_idx),
			0x49 => send_noret(&nodes[1], &nodes[0], chan_a, 10_000, &mut p_id, &mut p_idx),
			0x4a => send_noret(&nodes[1], &nodes[2], chan_b, 10_000, &mut p_id, &mut p_idx),
			0x4b => send_noret(&nodes[2], &nodes[1], chan_b, 10_000, &mut p_id, &mut p_idx),
			0x4c => send_hop_noret(
				&nodes[0], &nodes[1], chan_a, &nodes[2], chan_b, 10_000, &mut p_id, &mut p_idx,
			),
			0x4d => send_hop_noret(
				&nodes[2], &nodes[1], chan_b, &nodes[0], chan_a, 10_000, &mut p_id, &mut p_idx,
			),

			0x50 => send_noret(&nodes[0], &nodes[1], chan_a, 1_000, &mut p_id, &mut p_idx),
			0x51 => send_noret(&nodes[1], &nodes[0], chan_a, 1_000, &mut p_id, &mut p_idx),
			0x52 => send_noret(&nodes[1], &nodes[2], chan_b, 1_000, &mut p_id, &mut p_idx),
			0x53 => send_noret(&nodes[2], &nodes[1], chan_b, 1_000, &mut p_id, &mut p_idx),
			0x54 => send_hop_noret(
				&nodes[0], &nodes[1], chan_a, &nodes[2], chan_b, 1_000, &mut p_id, &mut p_idx,
			),
			0x55 => send_hop_noret(
				&nodes[2], &nodes[1], chan_b, &nodes[0], chan_a, 1_000, &mut p_id, &mut p_idx,
			),

			0x58 => send_noret(&nodes[0], &nodes[1], chan_a, 100, &mut p_id, &mut p_idx),
			0x59 => send_noret(&nodes[1], &nodes[0], chan_a, 100, &mut p_id, &mut p_idx),
			0x5a => send_noret(&nodes[1], &nodes[2], chan_b, 100, &mut p_id, &mut p_idx),
			0x5b => send_noret(&nodes[2], &nodes[1], chan_b, 100, &mut p_id, &mut p_idx),
			0x5c => send_hop_noret(
				&nodes[0], &nodes[1], chan_a, &nodes[2], chan_b, 100, &mut p_id, &mut p_idx,
			),
			0x5d => send_hop_noret(
				&nodes[2], &nodes[1], chan_b, &nodes[0], chan_a, 100, &mut p_id, &mut p_idx,
			),

			0x60 => send_noret(&nodes[0], &nodes[1], chan_a, 10, &mut p_id, &mut p_idx),
			0x61 => send_noret(&nodes[1], &nodes[0], chan_a, 10, &mut p_id, &mut p_idx),
			0x62 => send_noret(&nodes[1], &nodes[2], chan_b, 10, &mut p_id, &mut p_idx),
			0x63 => send_noret(&nodes[2], &nodes[1], chan_b, 10, &mut p_id, &mut p_idx),
			0x64 => send_hop_noret(
				&nodes[0], &nodes[1], chan_a, &nodes[2], chan_b, 10, &mut p_id, &mut p_idx,
			),
			0x65 => send_hop_noret(
				&nodes[2], &nodes[1], chan_b, &nodes[0], chan_a, 10, &mut p_id, &mut p_idx,
			),

			0x68 => send_noret(&nodes[0], &nodes[1], chan_a, 1, &mut p_id, &mut p_idx),
			0x69 => send_noret(&nodes[1], &nodes[0], chan_a, 1, &mut p_id, &mut p_idx),
			0x6a => send_noret(&nodes[1], &nodes[2], chan_b, 1, &mut p_id, &mut p_idx),
			0x6b => send_noret(&nodes[2], &nodes[1], chan_b, 1, &mut p_id, &mut p_idx),
			0x6c => send_hop_noret(
				&nodes[0], &nodes[1], chan_a, &nodes[2], chan_b, 1, &mut p_id, &mut p_idx,
			),
			0x6d => send_hop_noret(
				&nodes[2], &nodes[1], chan_b, &nodes[0], chan_a, 1, &mut p_id, &mut p_idx,
			),

			0x80 => {
				let mut max_feerate = last_htlc_clear_fee_a;
				if !anchors {
					max_feerate *= 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 mut max_feerate = last_htlc_clear_fee_b;
				if !anchors {
					max_feerate *= 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 mut max_feerate = last_htlc_clear_fee_c;
				if !anchors {
					max_feerate *= 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();
			},

			0xa0 => {
				nodes[0].maybe_propose_quiescence(&nodes[1].get_our_node_id(), &chan_a_id).unwrap()
			},
			0xa1 => {
				nodes[1].maybe_propose_quiescence(&nodes[0].get_our_node_id(), &chan_a_id).unwrap()
			},
			0xa2 => {
				nodes[1].maybe_propose_quiescence(&nodes[2].get_our_node_id(), &chan_b_id).unwrap()
			},
			0xa3 => {
				nodes[2].maybe_propose_quiescence(&nodes[1].get_our_node_id(), &chan_b_id).unwrap()
			},

			0xf0 => complete_monitor_update(&monitor_a, &chan_1_id, &complete_first),
			0xf1 => complete_monitor_update(&monitor_a, &chan_1_id, &complete_second),
			0xf2 => complete_monitor_update(&monitor_a, &chan_1_id, &Vec::pop),

			0xf4 => complete_monitor_update(&monitor_b, &chan_1_id, &complete_first),
			0xf5 => complete_monitor_update(&monitor_b, &chan_1_id, &complete_second),
			0xf6 => complete_monitor_update(&monitor_b, &chan_1_id, &Vec::pop),

			0xf8 => complete_monitor_update(&monitor_b, &chan_2_id, &complete_first),
			0xf9 => complete_monitor_update(&monitor_b, &chan_2_id, &complete_second),
			0xfa => complete_monitor_update(&monitor_b, &chan_2_id, &Vec::pop),

			0xfc => complete_monitor_update(&monitor_c, &chan_2_id, &complete_first),
			0xfd => complete_monitor_update(&monitor_c, &chan_2_id, &complete_second),
			0xfe => complete_monitor_update(&monitor_c, &chan_2_id, &Vec::pop),

			0xff => {
				// Test that no channel is in a stuck state where neither party can send funds even
				// after we resolve all pending events.
				// First make sure there are no pending monitor updates and further update
				// operations complete.
				*monitor_a.persister.update_ret.lock().unwrap() =
					ChannelMonitorUpdateStatus::Completed;
				*monitor_b.persister.update_ret.lock().unwrap() =
					ChannelMonitorUpdateStatus::Completed;
				*monitor_c.persister.update_ret.lock().unwrap() =
					ChannelMonitorUpdateStatus::Completed;

				complete_all_monitor_updates(&monitor_a, &chan_1_id);
				complete_all_monitor_updates(&monitor_b, &chan_1_id);
				complete_all_monitor_updates(&monitor_b, &chan_2_id);
				complete_all_monitor_updates(&monitor_c, &chan_2_id);

				// Next, make sure peers are all connected to each other
				if chan_a_disconnected {
					let init_1 = Init {
						features: nodes[1].init_features(),
						networks: None,
						remote_network_address: None,
					};
					nodes[0].peer_connected(nodes[1].get_our_node_id(), &init_1, true).unwrap();
					let init_0 = Init {
						features: nodes[0].init_features(),
						networks: None,
						remote_network_address: None,
					};
					nodes[1].peer_connected(nodes[0].get_our_node_id(), &init_0, false).unwrap();
					chan_a_disconnected = false;
				}
				if chan_b_disconnected {
					let init_2 = Init {
						features: nodes[2].init_features(),
						networks: None,
						remote_network_address: None,
					};
					nodes[1].peer_connected(nodes[2].get_our_node_id(), &init_2, true).unwrap();
					let init_1 = Init {
						features: nodes[1].init_features(),
						networks: None,
						remote_network_address: None,
					};
					nodes[2].peer_connected(nodes[1].get_our_node_id(), &init_1, false).unwrap();
					chan_b_disconnected = false;
				}

				macro_rules! process_all_events {
					() => {
						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, 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;
							}
							if process_events!(1, false) {
								continue;
							}
							if process_events!(2, false) {
								continue;
							}
							break;
						}
					};
				}

				// At this point, we may be pending quiescence, so we'll process all messages to
				// ensure we can complete its handshake. We'll then exit quiescence and process all
				// messages again, to resolve any pending HTLCs (only irrevocably committed ones)
				// before attempting to send more payments.
				process_all_events!();
				nodes[0].exit_quiescence(&nodes[1].get_our_node_id(), &chan_a_id).unwrap();
				nodes[1].exit_quiescence(&nodes[0].get_our_node_id(), &chan_a_id).unwrap();
				nodes[1].exit_quiescence(&nodes[2].get_our_node_id(), &chan_b_id).unwrap();
				nodes[2].exit_quiescence(&nodes[1].get_our_node_id(), &chan_b_id).unwrap();
				process_all_events!();

				// Finally, make sure that at least one end of each channel can make a substantial payment
				assert!(
					send_payment(&nodes[0], &nodes[1], chan_a, 10_000_000, &mut p_id, &mut p_idx)
						|| send_payment(
							&nodes[1], &nodes[0], chan_a, 10_000_000, &mut p_id, &mut p_idx
						)
				);
				assert!(
					send_payment(&nodes[1], &nodes[2], chan_b, 10_000_000, &mut p_id, &mut p_idx)
						|| send_payment(
							&nodes[2], &nodes[1], chan_b, 10_000_000, &mut p_id, &mut p_idx
						)
				);

				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!(),
		}

		if nodes[0].get_and_clear_needs_persistence() == true {
			node_a_ser.0.clear();
			nodes[0].write(&mut node_a_ser).unwrap();
		}
		if nodes[1].get_and_clear_needs_persistence() == true {
			node_b_ser.0.clear();
			nodes[1].write(&mut node_b_ser).unwrap();
		}
		if nodes[2].get_and_clear_needs_persistence() == true {
			node_c_ser.0.clear();
			nodes[2].write(&mut node_c_ser).unwrap();
		}
	}
}

/// We actually have different behavior based on if a certain log string has been seen, so we have
/// to do a bit more tracking.
#[derive(Clone)]
struct SearchingOutput<O: Output> {
	output: O,
	may_fail: Arc<atomic::AtomicBool>,
}
impl<O: Output> Output for SearchingOutput<O> {
	fn locked_write(&self, data: &[u8]) {
		// We hit a design limitation of LN state machine (see CONCURRENT_INBOUND_HTLC_FEE_BUFFER)
		if std::str::from_utf8(data).unwrap().contains("Outbound update_fee HTLC buffer overflow - counterparty should force-close this channel") {
			self.may_fail.store(true, atomic::Ordering::Release);
		}
		self.output.locked_write(data)
	}
}
impl<O: Output> SearchingOutput<O> {
	pub fn new(output: O) -> Self {
		Self { output, may_fail: Arc::new(atomic::AtomicBool::new(false)) }
	}
}

pub fn chanmon_consistency_test<Out: Output>(data: &[u8], out: Out) {
	do_test(data, out.clone(), false);
	do_test(data, out, true);
}

#[no_mangle]
pub extern "C" fn chanmon_consistency_run(data: *const u8, datalen: usize) {
	do_test(unsafe { std::slice::from_raw_parts(data, datalen) }, test_logger::DevNull {}, false);
	do_test(unsafe { std::slice::from_raw_parts(data, datalen) }, test_logger::DevNull {}, true);
}