Refactors in preparation for rust-bitcoin v0.30.0 update

.gitignore

@@ -10,4 +10,5 @@ Cargo.lock
 lightning/target
 lightning/ldk-net_graph-*.bin
 lightning-custom-message/target
+lightning-transaction-sync/target
 no-std-check/target

fuzz/src/chanmon_consistency.rs

@@ -18,8 +18,6 @@
 //! send-side handling is correct, other peers. We consider it a failure if any action results in a
 //! channel being force-closed.
 
-use bitcoin::TxMerkleNode;
-use bitcoin::blockdata::block::BlockHeader;
 use bitcoin::blockdata::constants::genesis_block;
 use bitcoin::blockdata::transaction::{Transaction, TxOut};
 use bitcoin::blockdata::script::{Builder, Script};
@@ -45,6 +43,7 @@ use lightning::ln::channelmanager::{ChainParameters, ChannelDetails, ChannelMana
 use lightning::ln::channel::FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE;
 use lightning::ln::msgs::{self, CommitmentUpdate, ChannelMessageHandler, DecodeError, UpdateAddHTLC, Init};
 use lightning::ln::script::ShutdownScript;
+use lightning::ln::functional_test_utils::*;
 use lightning::util::enforcing_trait_impls::{EnforcingSigner, EnforcementState};
 use lightning::util::errors::APIError;
 use lightning::util::logger::Logger;
@@ -547,11 +546,11 @@ pub fn do_test<Out: Output>(data: &[u8], underlying_out: Out) {
 	macro_rules! confirm_txn {
  ($node: expr) => { {
  let chain_hash = genesis_block(Network::Bitcoin).block_hash();
- let mut header = BlockHeader { version: 0x20000000, prev_blockhash: chain_hash, merkle_root: TxMerkleNode::all_zeros(), time: 42, bits: 42, nonce: 42 };
+ 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 = BlockHeader { version: 0x20000000, prev_blockhash: header.block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: 42, bits: 42, nonce: 42 };
+ header = create_dummy_header(header.block_hash(), 42);
  }
  $node.best_block_updated(&header, 99);
  } }

fuzz/src/full_stack.rs

@@ -13,8 +13,6 @@
 //! or payments to send/ways to handle events generated.
 //! This test has been very useful, though due to its complexity good starting inputs are critical.
 
-use bitcoin::TxMerkleNode;
-use bitcoin::blockdata::block::BlockHeader;
 use bitcoin::blockdata::constants::genesis_block;
 use bitcoin::blockdata::transaction::{Transaction, TxOut};
 use bitcoin::blockdata::script::{Builder, Script};
@@ -41,14 +39,15 @@ use lightning::ln::channelmanager::{ChainParameters, ChannelDetails, ChannelMana
 use lightning::ln::peer_handler::{MessageHandler,PeerManager,SocketDescriptor,IgnoringMessageHandler};
 use lightning::ln::msgs::{self, DecodeError};
 use lightning::ln::script::ShutdownScript;
+use lightning::ln::functional_test_utils::*;
 use lightning::routing::gossip::{P2PGossipSync, NetworkGraph};
 use lightning::routing::utxo::UtxoLookup;
 use lightning::routing::router::{InFlightHtlcs, PaymentParameters, Route, RouteParameters, Router};
 use lightning::util::config::UserConfig;
 use lightning::util::errors::APIError;
 use lightning::util::enforcing_trait_impls::{EnforcingSigner, EnforcementState};
 use lightning::util::logger::Logger;
-use lightning::util::ser::{Readable, ReadableArgs, Writeable};
+use lightning::util::ser::{ReadableArgs, Writeable};
 
 use crate::utils::test_logger;
 use crate::utils::test_persister::TestPersister;
@@ -228,7 +227,7 @@ impl<'a> MoneyLossDetector<'a> {
  }
 
  self.blocks_connected += 1;
- let header = BlockHeader { version: 0x20000000, prev_blockhash: self.header_hashes[self.height].0, merkle_root: TxMerkleNode::all_zeros(), time: self.blocks_connected, bits: 42, nonce: 42 };
+ let header = create_dummy_header(self.header_hashes[self.height].0, self.blocks_connected);
  self.height += 1;
  self.manager.transactions_confirmed(&header, &txdata, self.height as u32);
  self.manager.best_block_updated(&header, self.height as u32);
@@ -245,7 +244,7 @@ impl<'a> MoneyLossDetector<'a> {
 
 	fn disconnect_block(&mut self) {
  if self.height > 0 && (self.max_height < 6 || self.height >= self.max_height - 6) {
- let header = BlockHeader { version: 0x20000000, prev_blockhash: self.header_hashes[self.height - 1].0, merkle_root: TxMerkleNode::all_zeros(), time: self.header_hashes[self.height].1, bits: 42, nonce: 42 };
+ let header = create_dummy_header(self.header_hashes[self.height - 1].0, self.header_hashes[self.height].1);
  self.manager.block_disconnected(&header, self.height as u32);
  self.monitor.block_disconnected(&header, self.height as u32);
  self.height -= 1;

lightning-background-processor/src/lib.rs

@@ -817,7 +817,6 @@ impl Drop for BackgroundProcessor {
 
 #[cfg(all(feature = "std", test))]
 mod tests {
-	use bitcoin::blockdata::block::BlockHeader;
 	use bitcoin::blockdata::constants::genesis_block;
 	use bitcoin::blockdata::locktime::PackedLockTime;
 	use bitcoin::blockdata::transaction::{Transaction, TxOut};
@@ -833,6 +832,7 @@ mod tests {
 	use lightning::ln::channelmanager;
 	use lightning::ln::channelmanager::{BREAKDOWN_TIMEOUT, ChainParameters, MIN_CLTV_EXPIRY_DELTA, PaymentId};
 	use lightning::ln::features::{ChannelFeatures, NodeFeatures};
+	use lightning::ln::functional_test_utils::*;
 	use lightning::ln::msgs::{ChannelMessageHandler, Init};
 	use lightning::ln::peer_handler::{PeerManager, MessageHandler, SocketDescriptor, IgnoringMessageHandler};
 	use lightning::routing::gossip::{NetworkGraph, NodeId, P2PGossipSync};
@@ -849,8 +849,6 @@ mod tests {
 	use std::sync::{Arc, Mutex};
 	use std::sync::mpsc::SyncSender;
 	use std::time::Duration;
-	use bitcoin::hashes::Hash;
-	use bitcoin::TxMerkleNode;
 	use lightning_rapid_gossip_sync::RapidGossipSync;
 	use super::{BackgroundProcessor, GossipSync, FRESHNESS_TIMER};
 
@@ -1189,7 +1187,7 @@ mod tests {
  for i in 1..=depth {
  let prev_blockhash = node.best_block.block_hash();
  let height = node.best_block.height() + 1;
- let header = BlockHeader { version: 0x20000000, prev_blockhash, merkle_root: TxMerkleNode::all_zeros(), time: height, bits: 42, nonce: 42 };
+ let header = create_dummy_header(prev_blockhash, height);
  let txdata = vec![(0, tx)];
  node.best_block = BestBlock::new(header.block_hash(), height);
  match i {

lightning-block-sync/src/poll.rs

@@ -136,8 +136,11 @@ impl ValidatedBlockHeader {
 
  if let Network::Bitcoin = network {
  if self.height % 2016 == 0 {
- let previous_work = previous_header.header.work();
- if work > (previous_work << 2) || work < (previous_work >> 2) {
+ let target = self.header.target();
+ let previous_target = previous_header.header.target();
+ let min_target = previous_target >> 2;
+ let max_target = previous_target << 2;
+ if target > max_target || target < min_target {
  return Err(BlockSourceError::persistent("invalid difficulty transition"))
  }
  } else if self.header.bits != previous_header.header.bits {

lightning-persister/src/lib.rs

@@ -136,9 +136,8 @@ mod tests {
 	extern crate lightning;
 	extern crate bitcoin;
 	use crate::FilesystemPersister;
-	use bitcoin::blockdata::block::{Block, BlockHeader};
 	use bitcoin::hashes::hex::FromHex;
-	use bitcoin::{Txid, TxMerkleNode};
+	use bitcoin::Txid;
 	use lightning::chain::ChannelMonitorUpdateStatus;
 	use lightning::chain::chainmonitor::Persist;
 	use lightning::chain::channelmonitor::CLOSED_CHANNEL_UPDATE_ID;
@@ -148,7 +147,6 @@ mod tests {
 	use lightning::ln::functional_test_utils::*;
 	use lightning::util::test_utils;
 	use std::fs;
-	use bitcoin::hashes::Hash;
 	#[cfg(target_os = "windows")]
 	use {
  lightning::get_event_msg,
@@ -247,8 +245,7 @@ mod tests {
  let node_txn = nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap();
  assert_eq!(node_txn.len(), 1);
 
- let header = BlockHeader { version: 0x20000000, prev_blockhash: nodes[0].best_block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: 42, bits: 42, nonce: 42 };
- connect_block(&nodes[1], &Block { header, txdata: vec![node_txn[0].clone(), node_txn[0].clone()]});
+ connect_block(&nodes[1], &create_dummy_block(nodes[0].best_block_hash(), 42, vec![node_txn[0].clone(), node_txn[0].clone()]));
  check_closed_broadcast!(nodes[1], true);
  check_closed_event!(nodes[1], 1, ClosureReason::CommitmentTxConfirmed);
  check_added_monitors!(nodes[1], 1);

lightning/src/chain/chainmonitor.rs

@@ -825,8 +825,6 @@ impl<ChannelSigner: WriteableEcdsaChannelSigner, C: Deref, T: Deref, F: Deref, L
 
 #[cfg(test)]
 mod tests {
-	use bitcoin::{BlockHeader, TxMerkleNode};
-	use bitcoin::hashes::Hash;
 	use crate::{check_added_monitors, check_closed_broadcast, check_closed_event};
 	use crate::{expect_payment_sent, expect_payment_claimed, expect_payment_sent_without_paths, expect_payment_path_successful, get_event_msg};
 	use crate::{get_htlc_update_msgs, get_local_commitment_txn, get_revoke_commit_msgs, get_route_and_payment_hash, unwrap_send_err};
@@ -972,10 +970,7 @@ mod tests {
 
  // Connect B's commitment transaction, but only to the ChainMonitor/ChannelMonitor. The
  // channel is now closed, but the ChannelManager doesn't know that yet.
- let new_header = BlockHeader {
- version: 2, time: 0, bits: 0, nonce: 0,
- prev_blockhash: nodes[0].best_block_info().0,
- merkle_root: TxMerkleNode::all_zeros() };
+ let new_header = create_dummy_header(nodes[0].best_block_info().0, 0);
  nodes[0].chain_monitor.chain_monitor.transactions_confirmed(&new_header,
  &[(0, &remote_txn[0]), (1, &remote_txn[1])], nodes[0].best_block_info().1 + 1);
  assert!(nodes[0].chain_monitor.release_pending_monitor_events().is_empty());
@@ -999,10 +994,7 @@ mod tests {
 
  if block_timeout {
  // After three blocks, pending MontiorEvents should be released either way.
- let latest_header = BlockHeader {
- version: 2, time: 0, bits: 0, nonce: 0,
- prev_blockhash: nodes[0].best_block_info().0,
- merkle_root: TxMerkleNode::all_zeros() };
+ let latest_header = create_dummy_header(nodes[0].best_block_info().0, 0);
  nodes[0].chain_monitor.chain_monitor.best_block_updated(&latest_header, nodes[0].best_block_info().1 + LATENCY_GRACE_PERIOD_BLOCKS);
  } else {
  let persistences = chanmon_cfgs[0].persister.chain_sync_monitor_persistences.lock().unwrap().clone();

lightning/src/chain/channelmonitor.rs

@@ -4084,7 +4084,6 @@ impl<'a, 'b, ES: EntropySource, SP: SignerProvider> ReadableArgs<(&'a ES, &'b SP
 
 #[cfg(test)]
 mod tests {
-	use bitcoin::blockdata::block::BlockHeader;
 	use bitcoin::blockdata::script::{Script, Builder};
 	use bitcoin::blockdata::opcodes;
 	use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, EcdsaSighashType};
@@ -4121,7 +4120,7 @@ mod tests {
 	use crate::util::ser::{ReadableArgs, Writeable};
 	use crate::sync::{Arc, Mutex};
 	use crate::io;
-	use bitcoin::{PackedLockTime, Sequence, TxMerkleNode, Witness};
+	use bitcoin::{PackedLockTime, Sequence, Witness};
 	use crate::prelude::*;
 
 	fn do_test_funding_spend_refuses_updates(use_local_txn: bool) {
@@ -4160,10 +4159,7 @@ mod tests {
 
  // Connect a commitment transaction, but only to the ChainMonitor/ChannelMonitor. The
  // channel is now closed, but the ChannelManager doesn't know that yet.
- let new_header = BlockHeader {
- version: 2, time: 0, bits: 0, nonce: 0,
- prev_blockhash: nodes[0].best_block_info().0,
- merkle_root: TxMerkleNode::all_zeros() };
+ let new_header = create_dummy_header(nodes[0].best_block_info().0, 0);
  let conf_height = nodes[0].best_block_info().1 + 1;
  nodes[1].chain_monitor.chain_monitor.transactions_confirmed(&new_header,
  &[(0, broadcast_tx)], conf_height);

lightning/src/ln/chanmon_update_fail_tests.rs

@@ -12,7 +12,6 @@
 //! There are a bunch of these as their handling is relatively error-prone so they are split out
 //! here. See also the chanmon_fail_consistency fuzz test.
 
-use bitcoin::blockdata::block::{Block, BlockHeader};
 use bitcoin::blockdata::constants::genesis_block;
 use bitcoin::hash_types::BlockHash;
 use bitcoin::network::constants::Network;
@@ -35,7 +34,6 @@ use crate::util::test_utils;
 
 use crate::io;
 use bitcoin::hashes::Hash;
-use bitcoin::TxMerkleNode;
 use crate::prelude::*;
 use crate::sync::{Arc, Mutex};
 
@@ -121,15 +119,7 @@ fn test_monitor_and_persister_update_fail() {
  assert_eq!(chain_mon.watch_channel(outpoint, new_monitor), ChannelMonitorUpdateStatus::Completed);
  chain_mon
 	};
-	let header = BlockHeader {
- version: 0x20000000,
- prev_blockhash: BlockHash::all_zeros(),
- merkle_root: TxMerkleNode::all_zeros(),
- time: 42,
- bits: 42,
- nonce: 42
-	};
-	chain_mon.chain_monitor.block_connected(&Block { header, txdata: vec![] }, 200);
+	chain_mon.chain_monitor.block_connected(&create_dummy_block(BlockHash::all_zeros(), 42, Vec::new()), 200);
 
 	// Set the persister's return value to be a InProgress.
 	persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);

lightning/src/ln/channelmanager.rs

@@ -9387,10 +9387,7 @@ pub mod bench {
 
  assert_eq!(&tx_broadcaster.txn_broadcasted.lock().unwrap()[..], &[tx.clone()]);
 
- let block = Block {
- header: BlockHeader { version: 0x20000000, prev_blockhash: BestBlock::from_network(network).block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: 42, bits: 42, nonce: 42 },
- txdata: vec![tx],
- };
+ let block = create_dummy_block(BestBlock::from_network(network).block_hash(), 42, vec![tx]);
  Listen::block_connected(&node_a, &block, 1);
  Listen::block_connected(&node_b, &block, 1);
 

lightning/src/ln/functional_test_utils.rs

@@ -85,16 +85,14 @@ pub fn confirm_transactions_at<'a, 'b, 'c, 'd>(node: &'a Node<'b, 'c, 'd>, txn:
 	if conf_height > first_connect_height {
  connect_blocks(node, conf_height - first_connect_height);
 	}
-	let mut block = Block {
- header: BlockHeader { version: 0x20000000, prev_blockhash: node.best_block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: conf_height, bits: 42, nonce: 42 },
- txdata: Vec::new(),
-	};
+	let mut txdata = Vec::new();
 	for _ in 0..*node.network_chan_count.borrow() { // Make sure we don't end up with channels at the same short id by offsetting by chan_count
-block.txdata.push(Transaction { version: 0, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() });
+ txdata.push(Transaction { version: 0, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() });
 	}
 	for tx in txn {
-block.txdata.push((*tx).clone());
+ txdata.push((*tx).clone());
 	}
+	let block = create_dummy_block(node.best_block_hash(), conf_height, txdata);
 	connect_block(node, &block);
 	scid_utils::scid_from_parts(conf_height as u64, block.txdata.len() as u64 - 1, 0).unwrap()
 }
@@ -191,22 +189,31 @@ impl ConnectStyle {
 	}
 }
 
+pub fn create_dummy_header(prev_blockhash: BlockHash, time: u32) -> BlockHeader {
+	BlockHeader {
+ version: 0x2000_0000,
+ prev_blockhash,
+ merkle_root: TxMerkleNode::all_zeros(),
+ time,
+ bits: 42,
+ nonce: 42,
+	}
+}
+
+pub fn create_dummy_block(prev_blockhash: BlockHash, time: u32, txdata: Vec<Transaction>) -> Block {
+	Block { header: create_dummy_header(prev_blockhash, time), txdata }
+}
+
 pub fn connect_blocks<'a, 'b, 'c, 'd>(node: &'a Node<'b, 'c, 'd>, depth: u32) -> BlockHash {
 	let skip_intermediaries = node.connect_style.borrow().skips_blocks();
 
 	let height = node.best_block_info().1 + 1;
-	let mut block = Block {
- header: BlockHeader { version: 0x2000000, prev_blockhash: node.best_block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: height, bits: 42, nonce: 42 },
- txdata: vec![],
-	};
+	let mut block = create_dummy_block(node.best_block_hash(), height, Vec::new());
 	assert!(depth >= 1);
 	for i in 1..depth {
  let prev_blockhash = block.header.block_hash();
  do_connect_block(node, block, skip_intermediaries);
- block = Block {
- header: BlockHeader { version: 0x20000000, prev_blockhash, merkle_root: TxMerkleNode::all_zeros(), time: height + i, bits: 42, nonce: 42 },
- txdata: vec![],
- };
+ block = create_dummy_block(prev_blockhash, height + i, Vec::new());
 	}
 	let hash = block.header.block_hash();
 	do_connect_block(node, block, false);

.gitignore

@@ -10,4 +10,5 @@ Cargo.lock
 lightning/target
 lightning/ldk-net_graph-*.bin
 lightning-custom-message/target
+lightning-transaction-sync/target
 no-std-check/target

fuzz/src/chanmon_consistency.rs

@@ -18,8 +18,6 @@
 //! send-side handling is correct, other peers. We consider it a failure if any action results in a
 //! channel being force-closed.
 
-use bitcoin::TxMerkleNode;
-use bitcoin::blockdata::block::BlockHeader;
 use bitcoin::blockdata::constants::genesis_block;
 use bitcoin::blockdata::transaction::{Transaction, TxOut};
 use bitcoin::blockdata::script::{Builder, Script};
@@ -45,6 +43,7 @@ use lightning::ln::channelmanager::{ChainParameters, ChannelDetails, ChannelMana
 use lightning::ln::channel::FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE;
 use lightning::ln::msgs::{self, CommitmentUpdate, ChannelMessageHandler, DecodeError, UpdateAddHTLC, Init};
 use lightning::ln::script::ShutdownScript;
+use lightning::ln::functional_test_utils::*;
 use lightning::util::enforcing_trait_impls::{EnforcingSigner, EnforcementState};
 use lightning::util::errors::APIError;
 use lightning::util::logger::Logger;
@@ -547,11 +546,11 @@ pub fn do_test<Out: Output>(data: &[u8], underlying_out: Out) {
 	macro_rules! confirm_txn {
  ($node: expr) => { {
  let chain_hash = genesis_block(Network::Bitcoin).block_hash();
- let mut header = BlockHeader { version: 0x20000000, prev_blockhash: chain_hash, merkle_root: TxMerkleNode::all_zeros(), time: 42, bits: 42, nonce: 42 };
+ 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 = BlockHeader { version: 0x20000000, prev_blockhash: header.block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: 42, bits: 42, nonce: 42 };
+ header = create_dummy_header(header.block_hash(), 42);
  }
  $node.best_block_updated(&header, 99);
  } }

fuzz/src/full_stack.rs

@@ -13,8 +13,6 @@
 //! or payments to send/ways to handle events generated.
 //! This test has been very useful, though due to its complexity good starting inputs are critical.
 
-use bitcoin::TxMerkleNode;
-use bitcoin::blockdata::block::BlockHeader;
 use bitcoin::blockdata::constants::genesis_block;
 use bitcoin::blockdata::transaction::{Transaction, TxOut};
 use bitcoin::blockdata::script::{Builder, Script};
@@ -41,14 +39,15 @@ use lightning::ln::channelmanager::{ChainParameters, ChannelDetails, ChannelMana
 use lightning::ln::peer_handler::{MessageHandler,PeerManager,SocketDescriptor,IgnoringMessageHandler};
 use lightning::ln::msgs::{self, DecodeError};
 use lightning::ln::script::ShutdownScript;
+use lightning::ln::functional_test_utils::*;
 use lightning::routing::gossip::{P2PGossipSync, NetworkGraph};
 use lightning::routing::utxo::UtxoLookup;
 use lightning::routing::router::{InFlightHtlcs, PaymentParameters, Route, RouteParameters, Router};
 use lightning::util::config::UserConfig;
 use lightning::util::errors::APIError;
 use lightning::util::enforcing_trait_impls::{EnforcingSigner, EnforcementState};
 use lightning::util::logger::Logger;
-use lightning::util::ser::{Readable, ReadableArgs, Writeable};
+use lightning::util::ser::{ReadableArgs, Writeable};
 
 use crate::utils::test_logger;
 use crate::utils::test_persister::TestPersister;
@@ -228,7 +227,7 @@ impl<'a> MoneyLossDetector<'a> {
  }
 
  self.blocks_connected += 1;
- let header = BlockHeader { version: 0x20000000, prev_blockhash: self.header_hashes[self.height].0, merkle_root: TxMerkleNode::all_zeros(), time: self.blocks_connected, bits: 42, nonce: 42 };
+ let header = create_dummy_header(self.header_hashes[self.height].0, self.blocks_connected);
  self.height += 1;
  self.manager.transactions_confirmed(&header, &txdata, self.height as u32);
  self.manager.best_block_updated(&header, self.height as u32);
@@ -245,7 +244,7 @@ impl<'a> MoneyLossDetector<'a> {
 
 	fn disconnect_block(&mut self) {
  if self.height > 0 && (self.max_height < 6 || self.height >= self.max_height - 6) {
- let header = BlockHeader { version: 0x20000000, prev_blockhash: self.header_hashes[self.height - 1].0, merkle_root: TxMerkleNode::all_zeros(), time: self.header_hashes[self.height].1, bits: 42, nonce: 42 };
+ let header = create_dummy_header(self.header_hashes[self.height - 1].0, self.header_hashes[self.height].1);
  self.manager.block_disconnected(&header, self.height as u32);
  self.monitor.block_disconnected(&header, self.height as u32);
  self.height -= 1;

lightning-background-processor/src/lib.rs

@@ -817,7 +817,6 @@ impl Drop for BackgroundProcessor {
 
 #[cfg(all(feature = "std", test))]
 mod tests {
-	use bitcoin::blockdata::block::BlockHeader;
 	use bitcoin::blockdata::constants::genesis_block;
 	use bitcoin::blockdata::locktime::PackedLockTime;
 	use bitcoin::blockdata::transaction::{Transaction, TxOut};
@@ -833,6 +832,7 @@ mod tests {
 	use lightning::ln::channelmanager;
 	use lightning::ln::channelmanager::{BREAKDOWN_TIMEOUT, ChainParameters, MIN_CLTV_EXPIRY_DELTA, PaymentId};
 	use lightning::ln::features::{ChannelFeatures, NodeFeatures};
+	use lightning::ln::functional_test_utils::*;
 	use lightning::ln::msgs::{ChannelMessageHandler, Init};
 	use lightning::ln::peer_handler::{PeerManager, MessageHandler, SocketDescriptor, IgnoringMessageHandler};
 	use lightning::routing::gossip::{NetworkGraph, NodeId, P2PGossipSync};
@@ -849,8 +849,6 @@ mod tests {
 	use std::sync::{Arc, Mutex};
 	use std::sync::mpsc::SyncSender;
 	use std::time::Duration;
-	use bitcoin::hashes::Hash;
-	use bitcoin::TxMerkleNode;
 	use lightning_rapid_gossip_sync::RapidGossipSync;
 	use super::{BackgroundProcessor, GossipSync, FRESHNESS_TIMER};
 
@@ -1189,7 +1187,7 @@ mod tests {
  for i in 1..=depth {
  let prev_blockhash = node.best_block.block_hash();
  let height = node.best_block.height() + 1;
- let header = BlockHeader { version: 0x20000000, prev_blockhash, merkle_root: TxMerkleNode::all_zeros(), time: height, bits: 42, nonce: 42 };
+ let header = create_dummy_header(prev_blockhash, height);
  let txdata = vec![(0, tx)];
  node.best_block = BestBlock::new(header.block_hash(), height);
  match i {

lightning-block-sync/src/poll.rs

@@ -136,8 +136,11 @@ impl ValidatedBlockHeader {
 
  if let Network::Bitcoin = network {
  if self.height % 2016 == 0 {
- let previous_work = previous_header.header.work();
- if work > (previous_work << 2) || work < (previous_work >> 2) {
+ let target = self.header.target();
+ let previous_target = previous_header.header.target();
+ let min_target = previous_target >> 2;
+ let max_target = previous_target << 2;
+ if target > max_target || target < min_target {
  return Err(BlockSourceError::persistent("invalid difficulty transition"))
  }
  } else if self.header.bits != previous_header.header.bits {

lightning-persister/src/lib.rs

@@ -136,9 +136,8 @@ mod tests {
 	extern crate lightning;
 	extern crate bitcoin;
 	use crate::FilesystemPersister;
-	use bitcoin::blockdata::block::{Block, BlockHeader};
 	use bitcoin::hashes::hex::FromHex;
-	use bitcoin::{Txid, TxMerkleNode};
+	use bitcoin::Txid;
 	use lightning::chain::ChannelMonitorUpdateStatus;
 	use lightning::chain::chainmonitor::Persist;
 	use lightning::chain::channelmonitor::CLOSED_CHANNEL_UPDATE_ID;
@@ -148,7 +147,6 @@ mod tests {
 	use lightning::ln::functional_test_utils::*;
 	use lightning::util::test_utils;
 	use std::fs;
-	use bitcoin::hashes::Hash;
 	#[cfg(target_os = "windows")]
 	use {
  lightning::get_event_msg,
@@ -247,8 +245,7 @@ mod tests {
  let node_txn = nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap();
  assert_eq!(node_txn.len(), 1);
 
- let header = BlockHeader { version: 0x20000000, prev_blockhash: nodes[0].best_block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: 42, bits: 42, nonce: 42 };
- connect_block(&nodes[1], &Block { header, txdata: vec![node_txn[0].clone(), node_txn[0].clone()]});
+ connect_block(&nodes[1], &create_dummy_block(nodes[0].best_block_hash(), 42, vec![node_txn[0].clone(), node_txn[0].clone()]));
  check_closed_broadcast!(nodes[1], true);
  check_closed_event!(nodes[1], 1, ClosureReason::CommitmentTxConfirmed);
  check_added_monitors!(nodes[1], 1);

lightning/src/chain/chainmonitor.rs

@@ -825,8 +825,6 @@ impl<ChannelSigner: WriteableEcdsaChannelSigner, C: Deref, T: Deref, F: Deref, L
 
 #[cfg(test)]
 mod tests {
-	use bitcoin::{BlockHeader, TxMerkleNode};
-	use bitcoin::hashes::Hash;
 	use crate::{check_added_monitors, check_closed_broadcast, check_closed_event};
 	use crate::{expect_payment_sent, expect_payment_claimed, expect_payment_sent_without_paths, expect_payment_path_successful, get_event_msg};
 	use crate::{get_htlc_update_msgs, get_local_commitment_txn, get_revoke_commit_msgs, get_route_and_payment_hash, unwrap_send_err};
@@ -972,10 +970,7 @@ mod tests {
 
  // Connect B's commitment transaction, but only to the ChainMonitor/ChannelMonitor. The
  // channel is now closed, but the ChannelManager doesn't know that yet.
- let new_header = BlockHeader {
- version: 2, time: 0, bits: 0, nonce: 0,
- prev_blockhash: nodes[0].best_block_info().0,
- merkle_root: TxMerkleNode::all_zeros() };
+ let new_header = create_dummy_header(nodes[0].best_block_info().0, 0);
  nodes[0].chain_monitor.chain_monitor.transactions_confirmed(&new_header,
  &[(0, &remote_txn[0]), (1, &remote_txn[1])], nodes[0].best_block_info().1 + 1);
  assert!(nodes[0].chain_monitor.release_pending_monitor_events().is_empty());
@@ -999,10 +994,7 @@ mod tests {
 
  if block_timeout {
  // After three blocks, pending MontiorEvents should be released either way.
- let latest_header = BlockHeader {
- version: 2, time: 0, bits: 0, nonce: 0,
- prev_blockhash: nodes[0].best_block_info().0,
- merkle_root: TxMerkleNode::all_zeros() };
+ let latest_header = create_dummy_header(nodes[0].best_block_info().0, 0);
  nodes[0].chain_monitor.chain_monitor.best_block_updated(&latest_header, nodes[0].best_block_info().1 + LATENCY_GRACE_PERIOD_BLOCKS);
  } else {
  let persistences = chanmon_cfgs[0].persister.chain_sync_monitor_persistences.lock().unwrap().clone();

lightning/src/chain/channelmonitor.rs

@@ -4084,7 +4084,6 @@ impl<'a, 'b, ES: EntropySource, SP: SignerProvider> ReadableArgs<(&'a ES, &'b SP
 
 #[cfg(test)]
 mod tests {
-	use bitcoin::blockdata::block::BlockHeader;
 	use bitcoin::blockdata::script::{Script, Builder};
 	use bitcoin::blockdata::opcodes;
 	use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, EcdsaSighashType};
@@ -4121,7 +4120,7 @@ mod tests {
 	use crate::util::ser::{ReadableArgs, Writeable};
 	use crate::sync::{Arc, Mutex};
 	use crate::io;
-	use bitcoin::{PackedLockTime, Sequence, TxMerkleNode, Witness};
+	use bitcoin::{PackedLockTime, Sequence, Witness};
 	use crate::prelude::*;
 
 	fn do_test_funding_spend_refuses_updates(use_local_txn: bool) {
@@ -4160,10 +4159,7 @@ mod tests {
 
  // Connect a commitment transaction, but only to the ChainMonitor/ChannelMonitor. The
  // channel is now closed, but the ChannelManager doesn't know that yet.
- let new_header = BlockHeader {
- version: 2, time: 0, bits: 0, nonce: 0,
- prev_blockhash: nodes[0].best_block_info().0,
- merkle_root: TxMerkleNode::all_zeros() };
+ let new_header = create_dummy_header(nodes[0].best_block_info().0, 0);
  let conf_height = nodes[0].best_block_info().1 + 1;
  nodes[1].chain_monitor.chain_monitor.transactions_confirmed(&new_header,
  &[(0, broadcast_tx)], conf_height);

lightning/src/ln/chanmon_update_fail_tests.rs

@@ -12,7 +12,6 @@
 //! There are a bunch of these as their handling is relatively error-prone so they are split out
 //! here. See also the chanmon_fail_consistency fuzz test.
 
-use bitcoin::blockdata::block::{Block, BlockHeader};
 use bitcoin::blockdata::constants::genesis_block;
 use bitcoin::hash_types::BlockHash;
 use bitcoin::network::constants::Network;
@@ -35,7 +34,6 @@ use crate::util::test_utils;
 
 use crate::io;
 use bitcoin::hashes::Hash;
-use bitcoin::TxMerkleNode;
 use crate::prelude::*;
 use crate::sync::{Arc, Mutex};
 
@@ -121,15 +119,7 @@ fn test_monitor_and_persister_update_fail() {
  assert_eq!(chain_mon.watch_channel(outpoint, new_monitor), ChannelMonitorUpdateStatus::Completed);
  chain_mon
 	};
-	let header = BlockHeader {
- version: 0x20000000,
- prev_blockhash: BlockHash::all_zeros(),
- merkle_root: TxMerkleNode::all_zeros(),
- time: 42,
- bits: 42,
- nonce: 42
-	};
-	chain_mon.chain_monitor.block_connected(&Block { header, txdata: vec![] }, 200);
+	chain_mon.chain_monitor.block_connected(&create_dummy_block(BlockHash::all_zeros(), 42, Vec::new()), 200);
 
 	// Set the persister's return value to be a InProgress.
 	persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);

lightning/src/ln/channelmanager.rs

@@ -9387,10 +9387,7 @@ pub mod bench {
 
  assert_eq!(&tx_broadcaster.txn_broadcasted.lock().unwrap()[..], &[tx.clone()]);
 
- let block = Block {
- header: BlockHeader { version: 0x20000000, prev_blockhash: BestBlock::from_network(network).block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: 42, bits: 42, nonce: 42 },
- txdata: vec![tx],
- };
+ let block = create_dummy_block(BestBlock::from_network(network).block_hash(), 42, vec![tx]);
  Listen::block_connected(&node_a, &block, 1);
  Listen::block_connected(&node_b, &block, 1);
 

lightning/src/ln/functional_test_utils.rs

@@ -85,16 +85,14 @@ pub fn confirm_transactions_at<'a, 'b, 'c, 'd>(node: &'a Node<'b, 'c, 'd>, txn:
 	if conf_height > first_connect_height {
  connect_blocks(node, conf_height - first_connect_height);
 	}
-	let mut block = Block {
- header: BlockHeader { version: 0x20000000, prev_blockhash: node.best_block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: conf_height, bits: 42, nonce: 42 },
- txdata: Vec::new(),
-	};
+	let mut txdata = Vec::new();
 	for _ in 0..*node.network_chan_count.borrow() { // Make sure we don't end up with channels at the same short id by offsetting by chan_count
-block.txdata.push(Transaction { version: 0, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() });
+ txdata.push(Transaction { version: 0, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() });
 	}
 	for tx in txn {
-block.txdata.push((*tx).clone());
+ txdata.push((*tx).clone());
 	}
+	let block = create_dummy_block(node.best_block_hash(), conf_height, txdata);
 	connect_block(node, &block);
 	scid_utils::scid_from_parts(conf_height as u64, block.txdata.len() as u64 - 1, 0).unwrap()
 }
@@ -191,22 +189,31 @@ impl ConnectStyle {
 	}
 }
 
+pub fn create_dummy_header(prev_blockhash: BlockHash, time: u32) -> BlockHeader {
+	BlockHeader {
+ version: 0x2000_0000,
+ prev_blockhash,
+ merkle_root: TxMerkleNode::all_zeros(),
+ time,
+ bits: 42,
+ nonce: 42,
+	}
+}
+
+pub fn create_dummy_block(prev_blockhash: BlockHash, time: u32, txdata: Vec<Transaction>) -> Block {
+	Block { header: create_dummy_header(prev_blockhash, time), txdata }
+}
+
 pub fn connect_blocks<'a, 'b, 'c, 'd>(node: &'a Node<'b, 'c, 'd>, depth: u32) -> BlockHash {
 	let skip_intermediaries = node.connect_style.borrow().skips_blocks();
 
 	let height = node.best_block_info().1 + 1;
-	let mut block = Block {
- header: BlockHeader { version: 0x2000000, prev_blockhash: node.best_block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: height, bits: 42, nonce: 42 },
- txdata: vec![],
-	};
+	let mut block = create_dummy_block(node.best_block_hash(), height, Vec::new());
 	assert!(depth >= 1);
 	for i in 1..depth {
  let prev_blockhash = block.header.block_hash();
  do_connect_block(node, block, skip_intermediaries);
- block = Block {
- header: BlockHeader { version: 0x20000000, prev_blockhash, merkle_root: TxMerkleNode::all_zeros(), time: height + i, bits: 42, nonce: 42 },
- txdata: vec![],
- };
+ block = create_dummy_block(prev_blockhash, height + i, Vec::new());
 	}
 	let hash = block.header.block_hash();
 	do_connect_block(node, block, false);

.gitignore

@@ -10,4 +10,5 @@ Cargo.lock
 lightning/target
 lightning/ldk-net_graph-*.bin
 lightning-custom-message/target
+lightning-transaction-sync/target
 no-std-check/target

fuzz/src/chanmon_consistency.rs

@@ -18,8 +18,6 @@
 //! send-side handling is correct, other peers. We consider it a failure if any action results in a
 //! channel being force-closed.
 
-use bitcoin::TxMerkleNode;
-use bitcoin::blockdata::block::BlockHeader;
 use bitcoin::blockdata::constants::genesis_block;
 use bitcoin::blockdata::transaction::{Transaction, TxOut};
 use bitcoin::blockdata::script::{Builder, Script};
@@ -45,6 +43,7 @@ use lightning::ln::channelmanager::{ChainParameters, ChannelDetails, ChannelMana
 use lightning::ln::channel::FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE;
 use lightning::ln::msgs::{self, CommitmentUpdate, ChannelMessageHandler, DecodeError, UpdateAddHTLC, Init};
 use lightning::ln::script::ShutdownScript;
+use lightning::ln::functional_test_utils::*;
 use lightning::util::enforcing_trait_impls::{EnforcingSigner, EnforcementState};
 use lightning::util::errors::APIError;
 use lightning::util::logger::Logger;
@@ -547,11 +546,11 @@ pub fn do_test<Out: Output>(data: &[u8], underlying_out: Out) {
 	macro_rules! confirm_txn {
  ($node: expr) => { {
  let chain_hash = genesis_block(Network::Bitcoin).block_hash();
- let mut header = BlockHeader { version: 0x20000000, prev_blockhash: chain_hash, merkle_root: TxMerkleNode::all_zeros(), time: 42, bits: 42, nonce: 42 };
+ 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 = BlockHeader { version: 0x20000000, prev_blockhash: header.block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: 42, bits: 42, nonce: 42 };
+ header = create_dummy_header(header.block_hash(), 42);
  }
  $node.best_block_updated(&header, 99);
  } }

fuzz/src/full_stack.rs

@@ -13,8 +13,6 @@
 //! or payments to send/ways to handle events generated.
 //! This test has been very useful, though due to its complexity good starting inputs are critical.
 
-use bitcoin::TxMerkleNode;
-use bitcoin::blockdata::block::BlockHeader;
 use bitcoin::blockdata::constants::genesis_block;
 use bitcoin::blockdata::transaction::{Transaction, TxOut};
 use bitcoin::blockdata::script::{Builder, Script};
@@ -41,14 +39,15 @@ use lightning::ln::channelmanager::{ChainParameters, ChannelDetails, ChannelMana
 use lightning::ln::peer_handler::{MessageHandler,PeerManager,SocketDescriptor,IgnoringMessageHandler};
 use lightning::ln::msgs::{self, DecodeError};
 use lightning::ln::script::ShutdownScript;
+use lightning::ln::functional_test_utils::*;
 use lightning::routing::gossip::{P2PGossipSync, NetworkGraph};
 use lightning::routing::utxo::UtxoLookup;
 use lightning::routing::router::{InFlightHtlcs, PaymentParameters, Route, RouteParameters, Router};
 use lightning::util::config::UserConfig;
 use lightning::util::errors::APIError;
 use lightning::util::enforcing_trait_impls::{EnforcingSigner, EnforcementState};
 use lightning::util::logger::Logger;
-use lightning::util::ser::{Readable, ReadableArgs, Writeable};
+use lightning::util::ser::{ReadableArgs, Writeable};
 
 use crate::utils::test_logger;
 use crate::utils::test_persister::TestPersister;
@@ -228,7 +227,7 @@ impl<'a> MoneyLossDetector<'a> {
  }
 
  self.blocks_connected += 1;
- let header = BlockHeader { version: 0x20000000, prev_blockhash: self.header_hashes[self.height].0, merkle_root: TxMerkleNode::all_zeros(), time: self.blocks_connected, bits: 42, nonce: 42 };
+ let header = create_dummy_header(self.header_hashes[self.height].0, self.blocks_connected);
  self.height += 1;
  self.manager.transactions_confirmed(&header, &txdata, self.height as u32);
  self.manager.best_block_updated(&header, self.height as u32);
@@ -245,7 +244,7 @@ impl<'a> MoneyLossDetector<'a> {
 
 	fn disconnect_block(&mut self) {
  if self.height > 0 && (self.max_height < 6 || self.height >= self.max_height - 6) {
- let header = BlockHeader { version: 0x20000000, prev_blockhash: self.header_hashes[self.height - 1].0, merkle_root: TxMerkleNode::all_zeros(), time: self.header_hashes[self.height].1, bits: 42, nonce: 42 };
+ let header = create_dummy_header(self.header_hashes[self.height - 1].0, self.header_hashes[self.height].1);
  self.manager.block_disconnected(&header, self.height as u32);
  self.monitor.block_disconnected(&header, self.height as u32);
  self.height -= 1;

lightning-background-processor/src/lib.rs

@@ -817,7 +817,6 @@ impl Drop for BackgroundProcessor {
 
 #[cfg(all(feature = "std", test))]
 mod tests {
-	use bitcoin::blockdata::block::BlockHeader;
 	use bitcoin::blockdata::constants::genesis_block;
 	use bitcoin::blockdata::locktime::PackedLockTime;
 	use bitcoin::blockdata::transaction::{Transaction, TxOut};
@@ -833,6 +832,7 @@ mod tests {
 	use lightning::ln::channelmanager;
 	use lightning::ln::channelmanager::{BREAKDOWN_TIMEOUT, ChainParameters, MIN_CLTV_EXPIRY_DELTA, PaymentId};
 	use lightning::ln::features::{ChannelFeatures, NodeFeatures};
+	use lightning::ln::functional_test_utils::*;
 	use lightning::ln::msgs::{ChannelMessageHandler, Init};
 	use lightning::ln::peer_handler::{PeerManager, MessageHandler, SocketDescriptor, IgnoringMessageHandler};
 	use lightning::routing::gossip::{NetworkGraph, NodeId, P2PGossipSync};
@@ -849,8 +849,6 @@ mod tests {
 	use std::sync::{Arc, Mutex};
 	use std::sync::mpsc::SyncSender;
 	use std::time::Duration;
-	use bitcoin::hashes::Hash;
-	use bitcoin::TxMerkleNode;
 	use lightning_rapid_gossip_sync::RapidGossipSync;
 	use super::{BackgroundProcessor, GossipSync, FRESHNESS_TIMER};
 
@@ -1189,7 +1187,7 @@ mod tests {
  for i in 1..=depth {
  let prev_blockhash = node.best_block.block_hash();
  let height = node.best_block.height() + 1;
- let header = BlockHeader { version: 0x20000000, prev_blockhash, merkle_root: TxMerkleNode::all_zeros(), time: height, bits: 42, nonce: 42 };
+ let header = create_dummy_header(prev_blockhash, height);
  let txdata = vec![(0, tx)];
  node.best_block = BestBlock::new(header.block_hash(), height);
  match i {

lightning-block-sync/src/poll.rs

@@ -136,8 +136,11 @@ impl ValidatedBlockHeader {
 
  if let Network::Bitcoin = network {
  if self.height % 2016 == 0 {
- let previous_work = previous_header.header.work();
- if work > (previous_work << 2) || work < (previous_work >> 2) {
+ let target = self.header.target();
+ let previous_target = previous_header.header.target();
+ let min_target = previous_target >> 2;
+ let max_target = previous_target << 2;
+ if target > max_target || target < min_target {
  return Err(BlockSourceError::persistent("invalid difficulty transition"))
  }
  } else if self.header.bits != previous_header.header.bits {

lightning-persister/src/lib.rs

@@ -136,9 +136,8 @@ mod tests {
 	extern crate lightning;
 	extern crate bitcoin;
 	use crate::FilesystemPersister;
-	use bitcoin::blockdata::block::{Block, BlockHeader};
 	use bitcoin::hashes::hex::FromHex;
-	use bitcoin::{Txid, TxMerkleNode};
+	use bitcoin::Txid;
 	use lightning::chain::ChannelMonitorUpdateStatus;
 	use lightning::chain::chainmonitor::Persist;
 	use lightning::chain::channelmonitor::CLOSED_CHANNEL_UPDATE_ID;
@@ -148,7 +147,6 @@ mod tests {
 	use lightning::ln::functional_test_utils::*;
 	use lightning::util::test_utils;
 	use std::fs;
-	use bitcoin::hashes::Hash;
 	#[cfg(target_os = "windows")]
 	use {
  lightning::get_event_msg,
@@ -247,8 +245,7 @@ mod tests {
  let node_txn = nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap();
  assert_eq!(node_txn.len(), 1);
 
- let header = BlockHeader { version: 0x20000000, prev_blockhash: nodes[0].best_block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: 42, bits: 42, nonce: 42 };
- connect_block(&nodes[1], &Block { header, txdata: vec![node_txn[0].clone(), node_txn[0].clone()]});
+ connect_block(&nodes[1], &create_dummy_block(nodes[0].best_block_hash(), 42, vec![node_txn[0].clone(), node_txn[0].clone()]));
  check_closed_broadcast!(nodes[1], true);
  check_closed_event!(nodes[1], 1, ClosureReason::CommitmentTxConfirmed);
  check_added_monitors!(nodes[1], 1);

lightning/src/chain/chainmonitor.rs

@@ -825,8 +825,6 @@ impl<ChannelSigner: WriteableEcdsaChannelSigner, C: Deref, T: Deref, F: Deref, L
 
 #[cfg(test)]
 mod tests {
-	use bitcoin::{BlockHeader, TxMerkleNode};
-	use bitcoin::hashes::Hash;
 	use crate::{check_added_monitors, check_closed_broadcast, check_closed_event};
 	use crate::{expect_payment_sent, expect_payment_claimed, expect_payment_sent_without_paths, expect_payment_path_successful, get_event_msg};
 	use crate::{get_htlc_update_msgs, get_local_commitment_txn, get_revoke_commit_msgs, get_route_and_payment_hash, unwrap_send_err};
@@ -972,10 +970,7 @@ mod tests {
 
  // Connect B's commitment transaction, but only to the ChainMonitor/ChannelMonitor. The
  // channel is now closed, but the ChannelManager doesn't know that yet.
- let new_header = BlockHeader {
- version: 2, time: 0, bits: 0, nonce: 0,
- prev_blockhash: nodes[0].best_block_info().0,
- merkle_root: TxMerkleNode::all_zeros() };
+ let new_header = create_dummy_header(nodes[0].best_block_info().0, 0);
  nodes[0].chain_monitor.chain_monitor.transactions_confirmed(&new_header,
  &[(0, &remote_txn[0]), (1, &remote_txn[1])], nodes[0].best_block_info().1 + 1);
  assert!(nodes[0].chain_monitor.release_pending_monitor_events().is_empty());
@@ -999,10 +994,7 @@ mod tests {
 
  if block_timeout {
  // After three blocks, pending MontiorEvents should be released either way.
- let latest_header = BlockHeader {
- version: 2, time: 0, bits: 0, nonce: 0,
- prev_blockhash: nodes[0].best_block_info().0,
- merkle_root: TxMerkleNode::all_zeros() };
+ let latest_header = create_dummy_header(nodes[0].best_block_info().0, 0);
  nodes[0].chain_monitor.chain_monitor.best_block_updated(&latest_header, nodes[0].best_block_info().1 + LATENCY_GRACE_PERIOD_BLOCKS);
  } else {
  let persistences = chanmon_cfgs[0].persister.chain_sync_monitor_persistences.lock().unwrap().clone();

lightning/src/chain/channelmonitor.rs

@@ -4084,7 +4084,6 @@ impl<'a, 'b, ES: EntropySource, SP: SignerProvider> ReadableArgs<(&'a ES, &'b SP
 
 #[cfg(test)]
 mod tests {
-	use bitcoin::blockdata::block::BlockHeader;
 	use bitcoin::blockdata::script::{Script, Builder};
 	use bitcoin::blockdata::opcodes;
 	use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, EcdsaSighashType};
@@ -4121,7 +4120,7 @@ mod tests {
 	use crate::util::ser::{ReadableArgs, Writeable};
 	use crate::sync::{Arc, Mutex};
 	use crate::io;
-	use bitcoin::{PackedLockTime, Sequence, TxMerkleNode, Witness};
+	use bitcoin::{PackedLockTime, Sequence, Witness};
 	use crate::prelude::*;
 
 	fn do_test_funding_spend_refuses_updates(use_local_txn: bool) {
@@ -4160,10 +4159,7 @@ mod tests {
 
  // Connect a commitment transaction, but only to the ChainMonitor/ChannelMonitor. The
  // channel is now closed, but the ChannelManager doesn't know that yet.
- let new_header = BlockHeader {
- version: 2, time: 0, bits: 0, nonce: 0,
- prev_blockhash: nodes[0].best_block_info().0,
- merkle_root: TxMerkleNode::all_zeros() };
+ let new_header = create_dummy_header(nodes[0].best_block_info().0, 0);
  let conf_height = nodes[0].best_block_info().1 + 1;
  nodes[1].chain_monitor.chain_monitor.transactions_confirmed(&new_header,
  &[(0, broadcast_tx)], conf_height);

lightning/src/ln/chanmon_update_fail_tests.rs

@@ -12,7 +12,6 @@
 //! There are a bunch of these as their handling is relatively error-prone so they are split out
 //! here. See also the chanmon_fail_consistency fuzz test.
 
-use bitcoin::blockdata::block::{Block, BlockHeader};
 use bitcoin::blockdata::constants::genesis_block;
 use bitcoin::hash_types::BlockHash;
 use bitcoin::network::constants::Network;
@@ -35,7 +34,6 @@ use crate::util::test_utils;
 
 use crate::io;
 use bitcoin::hashes::Hash;
-use bitcoin::TxMerkleNode;
 use crate::prelude::*;
 use crate::sync::{Arc, Mutex};
 
@@ -121,15 +119,7 @@ fn test_monitor_and_persister_update_fail() {
  assert_eq!(chain_mon.watch_channel(outpoint, new_monitor), ChannelMonitorUpdateStatus::Completed);
  chain_mon
 	};
-	let header = BlockHeader {
- version: 0x20000000,
- prev_blockhash: BlockHash::all_zeros(),
- merkle_root: TxMerkleNode::all_zeros(),
- time: 42,
- bits: 42,
- nonce: 42
-	};
-	chain_mon.chain_monitor.block_connected(&Block { header, txdata: vec![] }, 200);
+	chain_mon.chain_monitor.block_connected(&create_dummy_block(BlockHash::all_zeros(), 42, Vec::new()), 200);
 
 	// Set the persister's return value to be a InProgress.
 	persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);

lightning/src/ln/channelmanager.rs

@@ -9387,10 +9387,7 @@ pub mod bench {
 
  assert_eq!(&tx_broadcaster.txn_broadcasted.lock().unwrap()[..], &[tx.clone()]);
 
- let block = Block {
- header: BlockHeader { version: 0x20000000, prev_blockhash: BestBlock::from_network(network).block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: 42, bits: 42, nonce: 42 },
- txdata: vec![tx],
- };
+ let block = create_dummy_block(BestBlock::from_network(network).block_hash(), 42, vec![tx]);
  Listen::block_connected(&node_a, &block, 1);
  Listen::block_connected(&node_b, &block, 1);
 

lightning/src/ln/functional_test_utils.rs

@@ -85,16 +85,14 @@ pub fn confirm_transactions_at<'a, 'b, 'c, 'd>(node: &'a Node<'b, 'c, 'd>, txn:
 	if conf_height > first_connect_height {
  connect_blocks(node, conf_height - first_connect_height);
 	}
-	let mut block = Block {
- header: BlockHeader { version: 0x20000000, prev_blockhash: node.best_block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: conf_height, bits: 42, nonce: 42 },
- txdata: Vec::new(),
-	};
+	let mut txdata = Vec::new();
 	for _ in 0..*node.network_chan_count.borrow() { // Make sure we don't end up with channels at the same short id by offsetting by chan_count
-block.txdata.push(Transaction { version: 0, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() });
+ txdata.push(Transaction { version: 0, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() });
 	}
 	for tx in txn {
-block.txdata.push((*tx).clone());
+ txdata.push((*tx).clone());
 	}
+	let block = create_dummy_block(node.best_block_hash(), conf_height, txdata);
 	connect_block(node, &block);
 	scid_utils::scid_from_parts(conf_height as u64, block.txdata.len() as u64 - 1, 0).unwrap()
 }
@@ -191,22 +189,31 @@ impl ConnectStyle {
 	}
 }
 
+pub fn create_dummy_header(prev_blockhash: BlockHash, time: u32) -> BlockHeader {
+	BlockHeader {
+ version: 0x2000_0000,
+ prev_blockhash,
+ merkle_root: TxMerkleNode::all_zeros(),
+ time,
+ bits: 42,
+ nonce: 42,
+	}
+}
+
+pub fn create_dummy_block(prev_blockhash: BlockHash, time: u32, txdata: Vec<Transaction>) -> Block {
+	Block { header: create_dummy_header(prev_blockhash, time), txdata }
+}
+
 pub fn connect_blocks<'a, 'b, 'c, 'd>(node: &'a Node<'b, 'c, 'd>, depth: u32) -> BlockHash {
 	let skip_intermediaries = node.connect_style.borrow().skips_blocks();
 
 	let height = node.best_block_info().1 + 1;
-	let mut block = Block {
- header: BlockHeader { version: 0x2000000, prev_blockhash: node.best_block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: height, bits: 42, nonce: 42 },
- txdata: vec![],
-	};
+	let mut block = create_dummy_block(node.best_block_hash(), height, Vec::new());
 	assert!(depth >= 1);
 	for i in 1..depth {
  let prev_blockhash = block.header.block_hash();
  do_connect_block(node, block, skip_intermediaries);
- block = Block {
- header: BlockHeader { version: 0x20000000, prev_blockhash, merkle_root: TxMerkleNode::all_zeros(), time: height + i, bits: 42, nonce: 42 },
- txdata: vec![],
- };
+ block = create_dummy_block(prev_blockhash, height + i, Vec::new());
 	}
 	let hash = block.header.block_hash();
 	do_connect_block(node, block, false);

.gitignore

@@ -10,4 +10,5 @@ Cargo.lock
 lightning/target
 lightning/ldk-net_graph-*.bin
 lightning-custom-message/target
+lightning-transaction-sync/target
 no-std-check/target

fuzz/src/chanmon_consistency.rs

@@ -18,8 +18,6 @@
 //! send-side handling is correct, other peers. We consider it a failure if any action results in a
 //! channel being force-closed.
 
-use bitcoin::TxMerkleNode;
-use bitcoin::blockdata::block::BlockHeader;
 use bitcoin::blockdata::constants::genesis_block;
 use bitcoin::blockdata::transaction::{Transaction, TxOut};
 use bitcoin::blockdata::script::{Builder, Script};
@@ -45,6 +43,7 @@ use lightning::ln::channelmanager::{ChainParameters, ChannelDetails, ChannelMana
 use lightning::ln::channel::FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE;
 use lightning::ln::msgs::{self, CommitmentUpdate, ChannelMessageHandler, DecodeError, UpdateAddHTLC, Init};
 use lightning::ln::script::ShutdownScript;
+use lightning::ln::functional_test_utils::*;
 use lightning::util::enforcing_trait_impls::{EnforcingSigner, EnforcementState};
 use lightning::util::errors::APIError;
 use lightning::util::logger::Logger;
@@ -547,11 +546,11 @@ pub fn do_test<Out: Output>(data: &[u8], underlying_out: Out) {
 	macro_rules! confirm_txn {
  ($node: expr) => { {
  let chain_hash = genesis_block(Network::Bitcoin).block_hash();
- let mut header = BlockHeader { version: 0x20000000, prev_blockhash: chain_hash, merkle_root: TxMerkleNode::all_zeros(), time: 42, bits: 42, nonce: 42 };
+ 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 = BlockHeader { version: 0x20000000, prev_blockhash: header.block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: 42, bits: 42, nonce: 42 };
+ header = create_dummy_header(header.block_hash(), 42);
  }
  $node.best_block_updated(&header, 99);
  } }

fuzz/src/full_stack.rs

@@ -13,8 +13,6 @@
 //! or payments to send/ways to handle events generated.
 //! This test has been very useful, though due to its complexity good starting inputs are critical.
 
-use bitcoin::TxMerkleNode;
-use bitcoin::blockdata::block::BlockHeader;
 use bitcoin::blockdata::constants::genesis_block;
 use bitcoin::blockdata::transaction::{Transaction, TxOut};
 use bitcoin::blockdata::script::{Builder, Script};
@@ -41,14 +39,15 @@ use lightning::ln::channelmanager::{ChainParameters, ChannelDetails, ChannelMana
 use lightning::ln::peer_handler::{MessageHandler,PeerManager,SocketDescriptor,IgnoringMessageHandler};
 use lightning::ln::msgs::{self, DecodeError};
 use lightning::ln::script::ShutdownScript;
+use lightning::ln::functional_test_utils::*;
 use lightning::routing::gossip::{P2PGossipSync, NetworkGraph};
 use lightning::routing::utxo::UtxoLookup;
 use lightning::routing::router::{InFlightHtlcs, PaymentParameters, Route, RouteParameters, Router};
 use lightning::util::config::UserConfig;
 use lightning::util::errors::APIError;
 use lightning::util::enforcing_trait_impls::{EnforcingSigner, EnforcementState};
 use lightning::util::logger::Logger;
-use lightning::util::ser::{Readable, ReadableArgs, Writeable};
+use lightning::util::ser::{ReadableArgs, Writeable};
 
 use crate::utils::test_logger;
 use crate::utils::test_persister::TestPersister;
@@ -228,7 +227,7 @@ impl<'a> MoneyLossDetector<'a> {
  }
 
  self.blocks_connected += 1;
- let header = BlockHeader { version: 0x20000000, prev_blockhash: self.header_hashes[self.height].0, merkle_root: TxMerkleNode::all_zeros(), time: self.blocks_connected, bits: 42, nonce: 42 };
+ let header = create_dummy_header(self.header_hashes[self.height].0, self.blocks_connected);
  self.height += 1;
  self.manager.transactions_confirmed(&header, &txdata, self.height as u32);
  self.manager.best_block_updated(&header, self.height as u32);
@@ -245,7 +244,7 @@ impl<'a> MoneyLossDetector<'a> {
 
 	fn disconnect_block(&mut self) {
  if self.height > 0 && (self.max_height < 6 || self.height >= self.max_height - 6) {
- let header = BlockHeader { version: 0x20000000, prev_blockhash: self.header_hashes[self.height - 1].0, merkle_root: TxMerkleNode::all_zeros(), time: self.header_hashes[self.height].1, bits: 42, nonce: 42 };
+ let header = create_dummy_header(self.header_hashes[self.height - 1].0, self.header_hashes[self.height].1);
  self.manager.block_disconnected(&header, self.height as u32);
  self.monitor.block_disconnected(&header, self.height as u32);
  self.height -= 1;

lightning-background-processor/src/lib.rs

@@ -817,7 +817,6 @@ impl Drop for BackgroundProcessor {
 
 #[cfg(all(feature = "std", test))]
 mod tests {
-	use bitcoin::blockdata::block::BlockHeader;
 	use bitcoin::blockdata::constants::genesis_block;
 	use bitcoin::blockdata::locktime::PackedLockTime;
 	use bitcoin::blockdata::transaction::{Transaction, TxOut};
@@ -833,6 +832,7 @@ mod tests {
 	use lightning::ln::channelmanager;
 	use lightning::ln::channelmanager::{BREAKDOWN_TIMEOUT, ChainParameters, MIN_CLTV_EXPIRY_DELTA, PaymentId};
 	use lightning::ln::features::{ChannelFeatures, NodeFeatures};
+	use lightning::ln::functional_test_utils::*;
 	use lightning::ln::msgs::{ChannelMessageHandler, Init};
 	use lightning::ln::peer_handler::{PeerManager, MessageHandler, SocketDescriptor, IgnoringMessageHandler};
 	use lightning::routing::gossip::{NetworkGraph, NodeId, P2PGossipSync};
@@ -849,8 +849,6 @@ mod tests {
 	use std::sync::{Arc, Mutex};
 	use std::sync::mpsc::SyncSender;
 	use std::time::Duration;
-	use bitcoin::hashes::Hash;
-	use bitcoin::TxMerkleNode;
 	use lightning_rapid_gossip_sync::RapidGossipSync;
 	use super::{BackgroundProcessor, GossipSync, FRESHNESS_TIMER};
 
@@ -1189,7 +1187,7 @@ mod tests {
  for i in 1..=depth {
  let prev_blockhash = node.best_block.block_hash();
  let height = node.best_block.height() + 1;
- let header = BlockHeader { version: 0x20000000, prev_blockhash, merkle_root: TxMerkleNode::all_zeros(), time: height, bits: 42, nonce: 42 };
+ let header = create_dummy_header(prev_blockhash, height);
  let txdata = vec![(0, tx)];
  node.best_block = BestBlock::new(header.block_hash(), height);
  match i {

lightning-block-sync/src/poll.rs

@@ -136,8 +136,11 @@ impl ValidatedBlockHeader {
 
  if let Network::Bitcoin = network {
  if self.height % 2016 == 0 {
- let previous_work = previous_header.header.work();
- if work > (previous_work << 2) || work < (previous_work >> 2) {
+ let target = self.header.target();
+ let previous_target = previous_header.header.target();
+ let min_target = previous_target >> 2;
+ let max_target = previous_target << 2;
+ if target > max_target || target < min_target {
  return Err(BlockSourceError::persistent("invalid difficulty transition"))
  }
  } else if self.header.bits != previous_header.header.bits {

lightning-persister/src/lib.rs

@@ -136,9 +136,8 @@ mod tests {
 	extern crate lightning;
 	extern crate bitcoin;
 	use crate::FilesystemPersister;
-	use bitcoin::blockdata::block::{Block, BlockHeader};
 	use bitcoin::hashes::hex::FromHex;
-	use bitcoin::{Txid, TxMerkleNode};
+	use bitcoin::Txid;
 	use lightning::chain::ChannelMonitorUpdateStatus;
 	use lightning::chain::chainmonitor::Persist;
 	use lightning::chain::channelmonitor::CLOSED_CHANNEL_UPDATE_ID;
@@ -148,7 +147,6 @@ mod tests {
 	use lightning::ln::functional_test_utils::*;
 	use lightning::util::test_utils;
 	use std::fs;
-	use bitcoin::hashes::Hash;
 	#[cfg(target_os = "windows")]
 	use {
  lightning::get_event_msg,
@@ -247,8 +245,7 @@ mod tests {
  let node_txn = nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap();
  assert_eq!(node_txn.len(), 1);
 
- let header = BlockHeader { version: 0x20000000, prev_blockhash: nodes[0].best_block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: 42, bits: 42, nonce: 42 };
- connect_block(&nodes[1], &Block { header, txdata: vec![node_txn[0].clone(), node_txn[0].clone()]});
+ connect_block(&nodes[1], &create_dummy_block(nodes[0].best_block_hash(), 42, vec![node_txn[0].clone(), node_txn[0].clone()]));
  check_closed_broadcast!(nodes[1], true);
  check_closed_event!(nodes[1], 1, ClosureReason::CommitmentTxConfirmed);
  check_added_monitors!(nodes[1], 1);

lightning/src/chain/chainmonitor.rs

@@ -825,8 +825,6 @@ impl<ChannelSigner: WriteableEcdsaChannelSigner, C: Deref, T: Deref, F: Deref, L
 
 #[cfg(test)]
 mod tests {
-	use bitcoin::{BlockHeader, TxMerkleNode};
-	use bitcoin::hashes::Hash;
 	use crate::{check_added_monitors, check_closed_broadcast, check_closed_event};
 	use crate::{expect_payment_sent, expect_payment_claimed, expect_payment_sent_without_paths, expect_payment_path_successful, get_event_msg};
 	use crate::{get_htlc_update_msgs, get_local_commitment_txn, get_revoke_commit_msgs, get_route_and_payment_hash, unwrap_send_err};
@@ -972,10 +970,7 @@ mod tests {
 
  // Connect B's commitment transaction, but only to the ChainMonitor/ChannelMonitor. The
  // channel is now closed, but the ChannelManager doesn't know that yet.
- let new_header = BlockHeader {
- version: 2, time: 0, bits: 0, nonce: 0,
- prev_blockhash: nodes[0].best_block_info().0,
- merkle_root: TxMerkleNode::all_zeros() };
+ let new_header = create_dummy_header(nodes[0].best_block_info().0, 0);
  nodes[0].chain_monitor.chain_monitor.transactions_confirmed(&new_header,
  &[(0, &remote_txn[0]), (1, &remote_txn[1])], nodes[0].best_block_info().1 + 1);
  assert!(nodes[0].chain_monitor.release_pending_monitor_events().is_empty());
@@ -999,10 +994,7 @@ mod tests {
 
  if block_timeout {
  // After three blocks, pending MontiorEvents should be released either way.
- let latest_header = BlockHeader {
- version: 2, time: 0, bits: 0, nonce: 0,
- prev_blockhash: nodes[0].best_block_info().0,
- merkle_root: TxMerkleNode::all_zeros() };
+ let latest_header = create_dummy_header(nodes[0].best_block_info().0, 0);
  nodes[0].chain_monitor.chain_monitor.best_block_updated(&latest_header, nodes[0].best_block_info().1 + LATENCY_GRACE_PERIOD_BLOCKS);
  } else {
  let persistences = chanmon_cfgs[0].persister.chain_sync_monitor_persistences.lock().unwrap().clone();

lightning/src/chain/channelmonitor.rs

@@ -4084,7 +4084,6 @@ impl<'a, 'b, ES: EntropySource, SP: SignerProvider> ReadableArgs<(&'a ES, &'b SP
 
 #[cfg(test)]
 mod tests {
-	use bitcoin::blockdata::block::BlockHeader;
 	use bitcoin::blockdata::script::{Script, Builder};
 	use bitcoin::blockdata::opcodes;
 	use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, EcdsaSighashType};
@@ -4121,7 +4120,7 @@ mod tests {
 	use crate::util::ser::{ReadableArgs, Writeable};
 	use crate::sync::{Arc, Mutex};
 	use crate::io;
-	use bitcoin::{PackedLockTime, Sequence, TxMerkleNode, Witness};
+	use bitcoin::{PackedLockTime, Sequence, Witness};
 	use crate::prelude::*;
 
 	fn do_test_funding_spend_refuses_updates(use_local_txn: bool) {
@@ -4160,10 +4159,7 @@ mod tests {
 
  // Connect a commitment transaction, but only to the ChainMonitor/ChannelMonitor. The
  // channel is now closed, but the ChannelManager doesn't know that yet.
- let new_header = BlockHeader {
- version: 2, time: 0, bits: 0, nonce: 0,
- prev_blockhash: nodes[0].best_block_info().0,
- merkle_root: TxMerkleNode::all_zeros() };
+ let new_header = create_dummy_header(nodes[0].best_block_info().0, 0);
  let conf_height = nodes[0].best_block_info().1 + 1;
  nodes[1].chain_monitor.chain_monitor.transactions_confirmed(&new_header,
  &[(0, broadcast_tx)], conf_height);

lightning/src/ln/chanmon_update_fail_tests.rs

@@ -12,7 +12,6 @@
 //! There are a bunch of these as their handling is relatively error-prone so they are split out
 //! here. See also the chanmon_fail_consistency fuzz test.
 
-use bitcoin::blockdata::block::{Block, BlockHeader};
 use bitcoin::blockdata::constants::genesis_block;
 use bitcoin::hash_types::BlockHash;
 use bitcoin::network::constants::Network;
@@ -35,7 +34,6 @@ use crate::util::test_utils;
 
 use crate::io;
 use bitcoin::hashes::Hash;
-use bitcoin::TxMerkleNode;
 use crate::prelude::*;
 use crate::sync::{Arc, Mutex};
 
@@ -121,15 +119,7 @@ fn test_monitor_and_persister_update_fail() {
  assert_eq!(chain_mon.watch_channel(outpoint, new_monitor), ChannelMonitorUpdateStatus::Completed);
  chain_mon
 	};
-	let header = BlockHeader {
- version: 0x20000000,
- prev_blockhash: BlockHash::all_zeros(),
- merkle_root: TxMerkleNode::all_zeros(),
- time: 42,
- bits: 42,
- nonce: 42
-	};
-	chain_mon.chain_monitor.block_connected(&Block { header, txdata: vec![] }, 200);
+	chain_mon.chain_monitor.block_connected(&create_dummy_block(BlockHash::all_zeros(), 42, Vec::new()), 200);
 
 	// Set the persister's return value to be a InProgress.
 	persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);

lightning/src/ln/channelmanager.rs

@@ -9387,10 +9387,7 @@ pub mod bench {
 
  assert_eq!(&tx_broadcaster.txn_broadcasted.lock().unwrap()[..], &[tx.clone()]);
 
- let block = Block {
- header: BlockHeader { version: 0x20000000, prev_blockhash: BestBlock::from_network(network).block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: 42, bits: 42, nonce: 42 },
- txdata: vec![tx],
- };
+ let block = create_dummy_block(BestBlock::from_network(network).block_hash(), 42, vec![tx]);
  Listen::block_connected(&node_a, &block, 1);
  Listen::block_connected(&node_b, &block, 1);
 

lightning/src/ln/functional_test_utils.rs

@@ -85,16 +85,14 @@ pub fn confirm_transactions_at<'a, 'b, 'c, 'd>(node: &'a Node<'b, 'c, 'd>, txn:
 	if conf_height > first_connect_height {
  connect_blocks(node, conf_height - first_connect_height);
 	}
-	let mut block = Block {
- header: BlockHeader { version: 0x20000000, prev_blockhash: node.best_block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: conf_height, bits: 42, nonce: 42 },
- txdata: Vec::new(),
-	};
+	let mut txdata = Vec::new();
 	for _ in 0..*node.network_chan_count.borrow() { // Make sure we don't end up with channels at the same short id by offsetting by chan_count
-block.txdata.push(Transaction { version: 0, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() });
+ txdata.push(Transaction { version: 0, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() });
 	}
 	for tx in txn {
-block.txdata.push((*tx).clone());
+ txdata.push((*tx).clone());
 	}
+	let block = create_dummy_block(node.best_block_hash(), conf_height, txdata);
 	connect_block(node, &block);
 	scid_utils::scid_from_parts(conf_height as u64, block.txdata.len() as u64 - 1, 0).unwrap()
 }
@@ -191,22 +189,31 @@ impl ConnectStyle {
 	}
 }
 
+pub fn create_dummy_header(prev_blockhash: BlockHash, time: u32) -> BlockHeader {
+	BlockHeader {
+ version: 0x2000_0000,
+ prev_blockhash,
+ merkle_root: TxMerkleNode::all_zeros(),
+ time,
+ bits: 42,
+ nonce: 42,
+	}
+}
+
+pub fn create_dummy_block(prev_blockhash: BlockHash, time: u32, txdata: Vec<Transaction>) -> Block {
+	Block { header: create_dummy_header(prev_blockhash, time), txdata }
+}
+
 pub fn connect_blocks<'a, 'b, 'c, 'd>(node: &'a Node<'b, 'c, 'd>, depth: u32) -> BlockHash {
 	let skip_intermediaries = node.connect_style.borrow().skips_blocks();
 
 	let height = node.best_block_info().1 + 1;
-	let mut block = Block {
- header: BlockHeader { version: 0x2000000, prev_blockhash: node.best_block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: height, bits: 42, nonce: 42 },
- txdata: vec![],
-	};
+	let mut block = create_dummy_block(node.best_block_hash(), height, Vec::new());
 	assert!(depth >= 1);
 	for i in 1..depth {
  let prev_blockhash = block.header.block_hash();
  do_connect_block(node, block, skip_intermediaries);
- block = Block {
- header: BlockHeader { version: 0x20000000, prev_blockhash, merkle_root: TxMerkleNode::all_zeros(), time: height + i, bits: 42, nonce: 42 },
- txdata: vec![],
- };
+ block = create_dummy_block(prev_blockhash, height + i, Vec::new());
 	}
 	let hash = block.header.block_hash();
 	do_connect_block(node, block, false);

.gitignore

@@ -10,4 +10,5 @@ Cargo.lock
 lightning/target
 lightning/ldk-net_graph-*.bin
 lightning-custom-message/target
+lightning-transaction-sync/target
 no-std-check/target

fuzz/src/chanmon_consistency.rs

@@ -18,8 +18,6 @@
 //! send-side handling is correct, other peers. We consider it a failure if any action results in a
 //! channel being force-closed.
 
-use bitcoin::TxMerkleNode;
-use bitcoin::blockdata::block::BlockHeader;
 use bitcoin::blockdata::constants::genesis_block;
 use bitcoin::blockdata::transaction::{Transaction, TxOut};
 use bitcoin::blockdata::script::{Builder, Script};
@@ -45,6 +43,7 @@ use lightning::ln::channelmanager::{ChainParameters, ChannelDetails, ChannelMana
 use lightning::ln::channel::FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE;
 use lightning::ln::msgs::{self, CommitmentUpdate, ChannelMessageHandler, DecodeError, UpdateAddHTLC, Init};
 use lightning::ln::script::ShutdownScript;
+use lightning::ln::functional_test_utils::*;
 use lightning::util::enforcing_trait_impls::{EnforcingSigner, EnforcementState};
 use lightning::util::errors::APIError;
 use lightning::util::logger::Logger;
@@ -547,11 +546,11 @@ pub fn do_test<Out: Output>(data: &[u8], underlying_out: Out) {
 	macro_rules! confirm_txn {
  ($node: expr) => { {
  let chain_hash = genesis_block(Network::Bitcoin).block_hash();
- let mut header = BlockHeader { version: 0x20000000, prev_blockhash: chain_hash, merkle_root: TxMerkleNode::all_zeros(), time: 42, bits: 42, nonce: 42 };
+ 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 = BlockHeader { version: 0x20000000, prev_blockhash: header.block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: 42, bits: 42, nonce: 42 };
+ header = create_dummy_header(header.block_hash(), 42);
  }
  $node.best_block_updated(&header, 99);
  } }

fuzz/src/full_stack.rs

@@ -13,8 +13,6 @@
 //! or payments to send/ways to handle events generated.
 //! This test has been very useful, though due to its complexity good starting inputs are critical.
 
-use bitcoin::TxMerkleNode;
-use bitcoin::blockdata::block::BlockHeader;
 use bitcoin::blockdata::constants::genesis_block;
 use bitcoin::blockdata::transaction::{Transaction, TxOut};
 use bitcoin::blockdata::script::{Builder, Script};
@@ -41,14 +39,15 @@ use lightning::ln::channelmanager::{ChainParameters, ChannelDetails, ChannelMana
 use lightning::ln::peer_handler::{MessageHandler,PeerManager,SocketDescriptor,IgnoringMessageHandler};
 use lightning::ln::msgs::{self, DecodeError};
 use lightning::ln::script::ShutdownScript;
+use lightning::ln::functional_test_utils::*;
 use lightning::routing::gossip::{P2PGossipSync, NetworkGraph};
 use lightning::routing::utxo::UtxoLookup;
 use lightning::routing::router::{InFlightHtlcs, PaymentParameters, Route, RouteParameters, Router};
 use lightning::util::config::UserConfig;
 use lightning::util::errors::APIError;
 use lightning::util::enforcing_trait_impls::{EnforcingSigner, EnforcementState};
 use lightning::util::logger::Logger;
-use lightning::util::ser::{Readable, ReadableArgs, Writeable};
+use lightning::util::ser::{ReadableArgs, Writeable};
 
 use crate::utils::test_logger;
 use crate::utils::test_persister::TestPersister;
@@ -228,7 +227,7 @@ impl<'a> MoneyLossDetector<'a> {
  }
 
  self.blocks_connected += 1;
- let header = BlockHeader { version: 0x20000000, prev_blockhash: self.header_hashes[self.height].0, merkle_root: TxMerkleNode::all_zeros(), time: self.blocks_connected, bits: 42, nonce: 42 };
+ let header = create_dummy_header(self.header_hashes[self.height].0, self.blocks_connected);
  self.height += 1;
  self.manager.transactions_confirmed(&header, &txdata, self.height as u32);
  self.manager.best_block_updated(&header, self.height as u32);
@@ -245,7 +244,7 @@ impl<'a> MoneyLossDetector<'a> {
 
 	fn disconnect_block(&mut self) {
  if self.height > 0 && (self.max_height < 6 || self.height >= self.max_height - 6) {
- let header = BlockHeader { version: 0x20000000, prev_blockhash: self.header_hashes[self.height - 1].0, merkle_root: TxMerkleNode::all_zeros(), time: self.header_hashes[self.height].1, bits: 42, nonce: 42 };
+ let header = create_dummy_header(self.header_hashes[self.height - 1].0, self.header_hashes[self.height].1);
  self.manager.block_disconnected(&header, self.height as u32);
  self.monitor.block_disconnected(&header, self.height as u32);
  self.height -= 1;

lightning-background-processor/src/lib.rs

@@ -817,7 +817,6 @@ impl Drop for BackgroundProcessor {
 
 #[cfg(all(feature = "std", test))]
 mod tests {
-	use bitcoin::blockdata::block::BlockHeader;
 	use bitcoin::blockdata::constants::genesis_block;
 	use bitcoin::blockdata::locktime::PackedLockTime;
 	use bitcoin::blockdata::transaction::{Transaction, TxOut};
@@ -833,6 +832,7 @@ mod tests {
 	use lightning::ln::channelmanager;
 	use lightning::ln::channelmanager::{BREAKDOWN_TIMEOUT, ChainParameters, MIN_CLTV_EXPIRY_DELTA, PaymentId};
 	use lightning::ln::features::{ChannelFeatures, NodeFeatures};
+	use lightning::ln::functional_test_utils::*;
 	use lightning::ln::msgs::{ChannelMessageHandler, Init};
 	use lightning::ln::peer_handler::{PeerManager, MessageHandler, SocketDescriptor, IgnoringMessageHandler};
 	use lightning::routing::gossip::{NetworkGraph, NodeId, P2PGossipSync};
@@ -849,8 +849,6 @@ mod tests {
 	use std::sync::{Arc, Mutex};
 	use std::sync::mpsc::SyncSender;
 	use std::time::Duration;
-	use bitcoin::hashes::Hash;
-	use bitcoin::TxMerkleNode;
 	use lightning_rapid_gossip_sync::RapidGossipSync;
 	use super::{BackgroundProcessor, GossipSync, FRESHNESS_TIMER};
 
@@ -1189,7 +1187,7 @@ mod tests {
  for i in 1..=depth {
  let prev_blockhash = node.best_block.block_hash();
  let height = node.best_block.height() + 1;
- let header = BlockHeader { version: 0x20000000, prev_blockhash, merkle_root: TxMerkleNode::all_zeros(), time: height, bits: 42, nonce: 42 };
+ let header = create_dummy_header(prev_blockhash, height);
  let txdata = vec![(0, tx)];
  node.best_block = BestBlock::new(header.block_hash(), height);
  match i {

lightning-block-sync/src/poll.rs

@@ -136,8 +136,11 @@ impl ValidatedBlockHeader {
 
  if let Network::Bitcoin = network {
  if self.height % 2016 == 0 {
- let previous_work = previous_header.header.work();
- if work > (previous_work << 2) || work < (previous_work >> 2) {
+ let target = self.header.target();
+ let previous_target = previous_header.header.target();
+ let min_target = previous_target >> 2;
+ let max_target = previous_target << 2;
+ if target > max_target || target < min_target {
  return Err(BlockSourceError::persistent("invalid difficulty transition"))
  }
  } else if self.header.bits != previous_header.header.bits {

lightning-persister/src/lib.rs

@@ -136,9 +136,8 @@ mod tests {
 	extern crate lightning;
 	extern crate bitcoin;
 	use crate::FilesystemPersister;
-	use bitcoin::blockdata::block::{Block, BlockHeader};
 	use bitcoin::hashes::hex::FromHex;
-	use bitcoin::{Txid, TxMerkleNode};
+	use bitcoin::Txid;
 	use lightning::chain::ChannelMonitorUpdateStatus;
 	use lightning::chain::chainmonitor::Persist;
 	use lightning::chain::channelmonitor::CLOSED_CHANNEL_UPDATE_ID;
@@ -148,7 +147,6 @@ mod tests {
 	use lightning::ln::functional_test_utils::*;
 	use lightning::util::test_utils;
 	use std::fs;
-	use bitcoin::hashes::Hash;
 	#[cfg(target_os = "windows")]
 	use {
  lightning::get_event_msg,
@@ -247,8 +245,7 @@ mod tests {
  let node_txn = nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap();
  assert_eq!(node_txn.len(), 1);
 
- let header = BlockHeader { version: 0x20000000, prev_blockhash: nodes[0].best_block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: 42, bits: 42, nonce: 42 };
- connect_block(&nodes[1], &Block { header, txdata: vec![node_txn[0].clone(), node_txn[0].clone()]});
+ connect_block(&nodes[1], &create_dummy_block(nodes[0].best_block_hash(), 42, vec![node_txn[0].clone(), node_txn[0].clone()]));
  check_closed_broadcast!(nodes[1], true);
  check_closed_event!(nodes[1], 1, ClosureReason::CommitmentTxConfirmed);
  check_added_monitors!(nodes[1], 1);

lightning/src/chain/chainmonitor.rs

@@ -825,8 +825,6 @@ impl<ChannelSigner: WriteableEcdsaChannelSigner, C: Deref, T: Deref, F: Deref, L
 
 #[cfg(test)]
 mod tests {
-	use bitcoin::{BlockHeader, TxMerkleNode};
-	use bitcoin::hashes::Hash;
 	use crate::{check_added_monitors, check_closed_broadcast, check_closed_event};
 	use crate::{expect_payment_sent, expect_payment_claimed, expect_payment_sent_without_paths, expect_payment_path_successful, get_event_msg};
 	use crate::{get_htlc_update_msgs, get_local_commitment_txn, get_revoke_commit_msgs, get_route_and_payment_hash, unwrap_send_err};
@@ -972,10 +970,7 @@ mod tests {
 
  // Connect B's commitment transaction, but only to the ChainMonitor/ChannelMonitor. The
  // channel is now closed, but the ChannelManager doesn't know that yet.
- let new_header = BlockHeader {
- version: 2, time: 0, bits: 0, nonce: 0,
- prev_blockhash: nodes[0].best_block_info().0,
- merkle_root: TxMerkleNode::all_zeros() };
+ let new_header = create_dummy_header(nodes[0].best_block_info().0, 0);
  nodes[0].chain_monitor.chain_monitor.transactions_confirmed(&new_header,
  &[(0, &remote_txn[0]), (1, &remote_txn[1])], nodes[0].best_block_info().1 + 1);
  assert!(nodes[0].chain_monitor.release_pending_monitor_events().is_empty());
@@ -999,10 +994,7 @@ mod tests {
 
  if block_timeout {
  // After three blocks, pending MontiorEvents should be released either way.
- let latest_header = BlockHeader {
- version: 2, time: 0, bits: 0, nonce: 0,
- prev_blockhash: nodes[0].best_block_info().0,
- merkle_root: TxMerkleNode::all_zeros() };
+ let latest_header = create_dummy_header(nodes[0].best_block_info().0, 0);
  nodes[0].chain_monitor.chain_monitor.best_block_updated(&latest_header, nodes[0].best_block_info().1 + LATENCY_GRACE_PERIOD_BLOCKS);
  } else {
  let persistences = chanmon_cfgs[0].persister.chain_sync_monitor_persistences.lock().unwrap().clone();

lightning/src/chain/channelmonitor.rs

@@ -4084,7 +4084,6 @@ impl<'a, 'b, ES: EntropySource, SP: SignerProvider> ReadableArgs<(&'a ES, &'b SP
 
 #[cfg(test)]
 mod tests {
-	use bitcoin::blockdata::block::BlockHeader;
 	use bitcoin::blockdata::script::{Script, Builder};
 	use bitcoin::blockdata::opcodes;
 	use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, EcdsaSighashType};
@@ -4121,7 +4120,7 @@ mod tests {
 	use crate::util::ser::{ReadableArgs, Writeable};
 	use crate::sync::{Arc, Mutex};
 	use crate::io;
-	use bitcoin::{PackedLockTime, Sequence, TxMerkleNode, Witness};
+	use bitcoin::{PackedLockTime, Sequence, Witness};
 	use crate::prelude::*;
 
 	fn do_test_funding_spend_refuses_updates(use_local_txn: bool) {
@@ -4160,10 +4159,7 @@ mod tests {
 
  // Connect a commitment transaction, but only to the ChainMonitor/ChannelMonitor. The
  // channel is now closed, but the ChannelManager doesn't know that yet.
- let new_header = BlockHeader {
- version: 2, time: 0, bits: 0, nonce: 0,
- prev_blockhash: nodes[0].best_block_info().0,
- merkle_root: TxMerkleNode::all_zeros() };
+ let new_header = create_dummy_header(nodes[0].best_block_info().0, 0);
  let conf_height = nodes[0].best_block_info().1 + 1;
  nodes[1].chain_monitor.chain_monitor.transactions_confirmed(&new_header,
  &[(0, broadcast_tx)], conf_height);

lightning/src/ln/chanmon_update_fail_tests.rs

@@ -12,7 +12,6 @@
 //! There are a bunch of these as their handling is relatively error-prone so they are split out
 //! here. See also the chanmon_fail_consistency fuzz test.
 
-use bitcoin::blockdata::block::{Block, BlockHeader};
 use bitcoin::blockdata::constants::genesis_block;
 use bitcoin::hash_types::BlockHash;
 use bitcoin::network::constants::Network;
@@ -35,7 +34,6 @@ use crate::util::test_utils;
 
 use crate::io;
 use bitcoin::hashes::Hash;
-use bitcoin::TxMerkleNode;
 use crate::prelude::*;
 use crate::sync::{Arc, Mutex};
 
@@ -121,15 +119,7 @@ fn test_monitor_and_persister_update_fail() {
  assert_eq!(chain_mon.watch_channel(outpoint, new_monitor), ChannelMonitorUpdateStatus::Completed);
  chain_mon
 	};
-	let header = BlockHeader {
- version: 0x20000000,
- prev_blockhash: BlockHash::all_zeros(),
- merkle_root: TxMerkleNode::all_zeros(),
- time: 42,
- bits: 42,
- nonce: 42
-	};
-	chain_mon.chain_monitor.block_connected(&Block { header, txdata: vec![] }, 200);
+	chain_mon.chain_monitor.block_connected(&create_dummy_block(BlockHash::all_zeros(), 42, Vec::new()), 200);
 
 	// Set the persister's return value to be a InProgress.
 	persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);

lightning/src/ln/channelmanager.rs

@@ -9387,10 +9387,7 @@ pub mod bench {
 
  assert_eq!(&tx_broadcaster.txn_broadcasted.lock().unwrap()[..], &[tx.clone()]);
 
- let block = Block {
- header: BlockHeader { version: 0x20000000, prev_blockhash: BestBlock::from_network(network).block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: 42, bits: 42, nonce: 42 },
- txdata: vec![tx],
- };
+ let block = create_dummy_block(BestBlock::from_network(network).block_hash(), 42, vec![tx]);
  Listen::block_connected(&node_a, &block, 1);
  Listen::block_connected(&node_b, &block, 1);
 

lightning/src/ln/functional_test_utils.rs

@@ -85,16 +85,14 @@ pub fn confirm_transactions_at<'a, 'b, 'c, 'd>(node: &'a Node<'b, 'c, 'd>, txn:
 	if conf_height > first_connect_height {
  connect_blocks(node, conf_height - first_connect_height);
 	}
-	let mut block = Block {
- header: BlockHeader { version: 0x20000000, prev_blockhash: node.best_block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: conf_height, bits: 42, nonce: 42 },
- txdata: Vec::new(),
-	};
+	let mut txdata = Vec::new();
 	for _ in 0..*node.network_chan_count.borrow() { // Make sure we don't end up with channels at the same short id by offsetting by chan_count
-block.txdata.push(Transaction { version: 0, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() });
+ txdata.push(Transaction { version: 0, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() });
 	}
 	for tx in txn {
-block.txdata.push((*tx).clone());
+ txdata.push((*tx).clone());
 	}
+	let block = create_dummy_block(node.best_block_hash(), conf_height, txdata);
 	connect_block(node, &block);
 	scid_utils::scid_from_parts(conf_height as u64, block.txdata.len() as u64 - 1, 0).unwrap()
 }
@@ -191,22 +189,31 @@ impl ConnectStyle {
 	}
 }
 
+pub fn create_dummy_header(prev_blockhash: BlockHash, time: u32) -> BlockHeader {
+	BlockHeader {
+ version: 0x2000_0000,
+ prev_blockhash,
+ merkle_root: TxMerkleNode::all_zeros(),
+ time,
+ bits: 42,
+ nonce: 42,
+	}
+}
+
+pub fn create_dummy_block(prev_blockhash: BlockHash, time: u32, txdata: Vec<Transaction>) -> Block {
+	Block { header: create_dummy_header(prev_blockhash, time), txdata }
+}
+
 pub fn connect_blocks<'a, 'b, 'c, 'd>(node: &'a Node<'b, 'c, 'd>, depth: u32) -> BlockHash {
 	let skip_intermediaries = node.connect_style.borrow().skips_blocks();
 
 	let height = node.best_block_info().1 + 1;
-	let mut block = Block {
- header: BlockHeader { version: 0x2000000, prev_blockhash: node.best_block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: height, bits: 42, nonce: 42 },
- txdata: vec![],
-	};
+	let mut block = create_dummy_block(node.best_block_hash(), height, Vec::new());
 	assert!(depth >= 1);
 	for i in 1..depth {
  let prev_blockhash = block.header.block_hash();
  do_connect_block(node, block, skip_intermediaries);
- block = Block {
- header: BlockHeader { version: 0x20000000, prev_blockhash, merkle_root: TxMerkleNode::all_zeros(), time: height + i, bits: 42, nonce: 42 },
- txdata: vec![],
- };
+ block = create_dummy_block(prev_blockhash, height + i, Vec::new());
 	}
 	let hash = block.header.block_hash();
 	do_connect_block(node, block, false);

.gitignore

@@ -10,4 +10,5 @@ Cargo.lock
 lightning/target
 lightning/ldk-net_graph-*.bin
 lightning-custom-message/target
+lightning-transaction-sync/target
 no-std-check/target

fuzz/src/chanmon_consistency.rs

@@ -18,8 +18,6 @@
 //! send-side handling is correct, other peers. We consider it a failure if any action results in a
 //! channel being force-closed.
 
-use bitcoin::TxMerkleNode;
-use bitcoin::blockdata::block::BlockHeader;
 use bitcoin::blockdata::constants::genesis_block;
 use bitcoin::blockdata::transaction::{Transaction, TxOut};
 use bitcoin::blockdata::script::{Builder, Script};
@@ -45,6 +43,7 @@ use lightning::ln::channelmanager::{ChainParameters, ChannelDetails, ChannelMana
 use lightning::ln::channel::FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE;
 use lightning::ln::msgs::{self, CommitmentUpdate, ChannelMessageHandler, DecodeError, UpdateAddHTLC, Init};
 use lightning::ln::script::ShutdownScript;
+use lightning::ln::functional_test_utils::*;
 use lightning::util::enforcing_trait_impls::{EnforcingSigner, EnforcementState};
 use lightning::util::errors::APIError;
 use lightning::util::logger::Logger;
@@ -547,11 +546,11 @@ pub fn do_test<Out: Output>(data: &[u8], underlying_out: Out) {
 	macro_rules! confirm_txn {
  ($node: expr) => { {
  let chain_hash = genesis_block(Network::Bitcoin).block_hash();
- let mut header = BlockHeader { version: 0x20000000, prev_blockhash: chain_hash, merkle_root: TxMerkleNode::all_zeros(), time: 42, bits: 42, nonce: 42 };
+ 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 = BlockHeader { version: 0x20000000, prev_blockhash: header.block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: 42, bits: 42, nonce: 42 };
+ header = create_dummy_header(header.block_hash(), 42);
  }
  $node.best_block_updated(&header, 99);
  } }

fuzz/src/full_stack.rs

@@ -13,8 +13,6 @@
 //! or payments to send/ways to handle events generated.
 //! This test has been very useful, though due to its complexity good starting inputs are critical.
 
-use bitcoin::TxMerkleNode;
-use bitcoin::blockdata::block::BlockHeader;
 use bitcoin::blockdata::constants::genesis_block;
 use bitcoin::blockdata::transaction::{Transaction, TxOut};
 use bitcoin::blockdata::script::{Builder, Script};
@@ -41,14 +39,15 @@ use lightning::ln::channelmanager::{ChainParameters, ChannelDetails, ChannelMana
 use lightning::ln::peer_handler::{MessageHandler,PeerManager,SocketDescriptor,IgnoringMessageHandler};
 use lightning::ln::msgs::{self, DecodeError};
 use lightning::ln::script::ShutdownScript;
+use lightning::ln::functional_test_utils::*;
 use lightning::routing::gossip::{P2PGossipSync, NetworkGraph};
 use lightning::routing::utxo::UtxoLookup;
 use lightning::routing::router::{InFlightHtlcs, PaymentParameters, Route, RouteParameters, Router};
 use lightning::util::config::UserConfig;
 use lightning::util::errors::APIError;
 use lightning::util::enforcing_trait_impls::{EnforcingSigner, EnforcementState};
 use lightning::util::logger::Logger;
-use lightning::util::ser::{Readable, ReadableArgs, Writeable};
+use lightning::util::ser::{ReadableArgs, Writeable};
 
 use crate::utils::test_logger;
 use crate::utils::test_persister::TestPersister;
@@ -228,7 +227,7 @@ impl<'a> MoneyLossDetector<'a> {
  }
 
  self.blocks_connected += 1;
- let header = BlockHeader { version: 0x20000000, prev_blockhash: self.header_hashes[self.height].0, merkle_root: TxMerkleNode::all_zeros(), time: self.blocks_connected, bits: 42, nonce: 42 };
+ let header = create_dummy_header(self.header_hashes[self.height].0, self.blocks_connected);
  self.height += 1;
  self.manager.transactions_confirmed(&header, &txdata, self.height as u32);
  self.manager.best_block_updated(&header, self.height as u32);
@@ -245,7 +244,7 @@ impl<'a> MoneyLossDetector<'a> {
 
 	fn disconnect_block(&mut self) {
  if self.height > 0 && (self.max_height < 6 || self.height >= self.max_height - 6) {
- let header = BlockHeader { version: 0x20000000, prev_blockhash: self.header_hashes[self.height - 1].0, merkle_root: TxMerkleNode::all_zeros(), time: self.header_hashes[self.height].1, bits: 42, nonce: 42 };
+ let header = create_dummy_header(self.header_hashes[self.height - 1].0, self.header_hashes[self.height].1);
  self.manager.block_disconnected(&header, self.height as u32);
  self.monitor.block_disconnected(&header, self.height as u32);
  self.height -= 1;

lightning-background-processor/src/lib.rs

@@ -817,7 +817,6 @@ impl Drop for BackgroundProcessor {
 
 #[cfg(all(feature = "std", test))]
 mod tests {
-	use bitcoin::blockdata::block::BlockHeader;
 	use bitcoin::blockdata::constants::genesis_block;
 	use bitcoin::blockdata::locktime::PackedLockTime;
 	use bitcoin::blockdata::transaction::{Transaction, TxOut};
@@ -833,6 +832,7 @@ mod tests {
 	use lightning::ln::channelmanager;
 	use lightning::ln::channelmanager::{BREAKDOWN_TIMEOUT, ChainParameters, MIN_CLTV_EXPIRY_DELTA, PaymentId};
 	use lightning::ln::features::{ChannelFeatures, NodeFeatures};
+	use lightning::ln::functional_test_utils::*;
 	use lightning::ln::msgs::{ChannelMessageHandler, Init};
 	use lightning::ln::peer_handler::{PeerManager, MessageHandler, SocketDescriptor, IgnoringMessageHandler};
 	use lightning::routing::gossip::{NetworkGraph, NodeId, P2PGossipSync};
@@ -849,8 +849,6 @@ mod tests {
 	use std::sync::{Arc, Mutex};
 	use std::sync::mpsc::SyncSender;
 	use std::time::Duration;
-	use bitcoin::hashes::Hash;
-	use bitcoin::TxMerkleNode;
 	use lightning_rapid_gossip_sync::RapidGossipSync;
 	use super::{BackgroundProcessor, GossipSync, FRESHNESS_TIMER};
 
@@ -1189,7 +1187,7 @@ mod tests {
  for i in 1..=depth {
  let prev_blockhash = node.best_block.block_hash();
  let height = node.best_block.height() + 1;
- let header = BlockHeader { version: 0x20000000, prev_blockhash, merkle_root: TxMerkleNode::all_zeros(), time: height, bits: 42, nonce: 42 };
+ let header = create_dummy_header(prev_blockhash, height);
  let txdata = vec![(0, tx)];
  node.best_block = BestBlock::new(header.block_hash(), height);
  match i {

lightning-block-sync/src/poll.rs

@@ -136,8 +136,11 @@ impl ValidatedBlockHeader {
 
  if let Network::Bitcoin = network {
  if self.height % 2016 == 0 {
- let previous_work = previous_header.header.work();
- if work > (previous_work << 2) || work < (previous_work >> 2) {
+ let target = self.header.target();
+ let previous_target = previous_header.header.target();
+ let min_target = previous_target >> 2;
+ let max_target = previous_target << 2;
+ if target > max_target || target < min_target {
  return Err(BlockSourceError::persistent("invalid difficulty transition"))
  }
  } else if self.header.bits != previous_header.header.bits {

lightning-persister/src/lib.rs

@@ -136,9 +136,8 @@ mod tests {
 	extern crate lightning;
 	extern crate bitcoin;
 	use crate::FilesystemPersister;
-	use bitcoin::blockdata::block::{Block, BlockHeader};
 	use bitcoin::hashes::hex::FromHex;
-	use bitcoin::{Txid, TxMerkleNode};
+	use bitcoin::Txid;
 	use lightning::chain::ChannelMonitorUpdateStatus;
 	use lightning::chain::chainmonitor::Persist;
 	use lightning::chain::channelmonitor::CLOSED_CHANNEL_UPDATE_ID;
@@ -148,7 +147,6 @@ mod tests {
 	use lightning::ln::functional_test_utils::*;
 	use lightning::util::test_utils;
 	use std::fs;
-	use bitcoin::hashes::Hash;
 	#[cfg(target_os = "windows")]
 	use {
  lightning::get_event_msg,
@@ -247,8 +245,7 @@ mod tests {
  let node_txn = nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap();
  assert_eq!(node_txn.len(), 1);
 
- let header = BlockHeader { version: 0x20000000, prev_blockhash: nodes[0].best_block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: 42, bits: 42, nonce: 42 };
- connect_block(&nodes[1], &Block { header, txdata: vec![node_txn[0].clone(), node_txn[0].clone()]});
+ connect_block(&nodes[1], &create_dummy_block(nodes[0].best_block_hash(), 42, vec![node_txn[0].clone(), node_txn[0].clone()]));
  check_closed_broadcast!(nodes[1], true);
  check_closed_event!(nodes[1], 1, ClosureReason::CommitmentTxConfirmed);
  check_added_monitors!(nodes[1], 1);

lightning/src/chain/chainmonitor.rs

@@ -825,8 +825,6 @@ impl<ChannelSigner: WriteableEcdsaChannelSigner, C: Deref, T: Deref, F: Deref, L
 
 #[cfg(test)]
 mod tests {
-	use bitcoin::{BlockHeader, TxMerkleNode};
-	use bitcoin::hashes::Hash;
 	use crate::{check_added_monitors, check_closed_broadcast, check_closed_event};
 	use crate::{expect_payment_sent, expect_payment_claimed, expect_payment_sent_without_paths, expect_payment_path_successful, get_event_msg};
 	use crate::{get_htlc_update_msgs, get_local_commitment_txn, get_revoke_commit_msgs, get_route_and_payment_hash, unwrap_send_err};
@@ -972,10 +970,7 @@ mod tests {
 
  // Connect B's commitment transaction, but only to the ChainMonitor/ChannelMonitor. The
  // channel is now closed, but the ChannelManager doesn't know that yet.
- let new_header = BlockHeader {
- version: 2, time: 0, bits: 0, nonce: 0,
- prev_blockhash: nodes[0].best_block_info().0,
- merkle_root: TxMerkleNode::all_zeros() };
+ let new_header = create_dummy_header(nodes[0].best_block_info().0, 0);
  nodes[0].chain_monitor.chain_monitor.transactions_confirmed(&new_header,
  &[(0, &remote_txn[0]), (1, &remote_txn[1])], nodes[0].best_block_info().1 + 1);
  assert!(nodes[0].chain_monitor.release_pending_monitor_events().is_empty());
@@ -999,10 +994,7 @@ mod tests {
 
  if block_timeout {
  // After three blocks, pending MontiorEvents should be released either way.
- let latest_header = BlockHeader {
- version: 2, time: 0, bits: 0, nonce: 0,
- prev_blockhash: nodes[0].best_block_info().0,
- merkle_root: TxMerkleNode::all_zeros() };
+ let latest_header = create_dummy_header(nodes[0].best_block_info().0, 0);
  nodes[0].chain_monitor.chain_monitor.best_block_updated(&latest_header, nodes[0].best_block_info().1 + LATENCY_GRACE_PERIOD_BLOCKS);
  } else {
  let persistences = chanmon_cfgs[0].persister.chain_sync_monitor_persistences.lock().unwrap().clone();

lightning/src/chain/channelmonitor.rs

@@ -4084,7 +4084,6 @@ impl<'a, 'b, ES: EntropySource, SP: SignerProvider> ReadableArgs<(&'a ES, &'b SP
 
 #[cfg(test)]
 mod tests {
-	use bitcoin::blockdata::block::BlockHeader;
 	use bitcoin::blockdata::script::{Script, Builder};
 	use bitcoin::blockdata::opcodes;
 	use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, EcdsaSighashType};
@@ -4121,7 +4120,7 @@ mod tests {
 	use crate::util::ser::{ReadableArgs, Writeable};
 	use crate::sync::{Arc, Mutex};
 	use crate::io;
-	use bitcoin::{PackedLockTime, Sequence, TxMerkleNode, Witness};
+	use bitcoin::{PackedLockTime, Sequence, Witness};
 	use crate::prelude::*;
 
 	fn do_test_funding_spend_refuses_updates(use_local_txn: bool) {
@@ -4160,10 +4159,7 @@ mod tests {
 
  // Connect a commitment transaction, but only to the ChainMonitor/ChannelMonitor. The
  // channel is now closed, but the ChannelManager doesn't know that yet.
- let new_header = BlockHeader {
- version: 2, time: 0, bits: 0, nonce: 0,
- prev_blockhash: nodes[0].best_block_info().0,
- merkle_root: TxMerkleNode::all_zeros() };
+ let new_header = create_dummy_header(nodes[0].best_block_info().0, 0);
  let conf_height = nodes[0].best_block_info().1 + 1;
  nodes[1].chain_monitor.chain_monitor.transactions_confirmed(&new_header,
  &[(0, broadcast_tx)], conf_height);

lightning/src/ln/chanmon_update_fail_tests.rs

@@ -12,7 +12,6 @@
 //! There are a bunch of these as their handling is relatively error-prone so they are split out
 //! here. See also the chanmon_fail_consistency fuzz test.
 
-use bitcoin::blockdata::block::{Block, BlockHeader};
 use bitcoin::blockdata::constants::genesis_block;
 use bitcoin::hash_types::BlockHash;
 use bitcoin::network::constants::Network;
@@ -35,7 +34,6 @@ use crate::util::test_utils;
 
 use crate::io;
 use bitcoin::hashes::Hash;
-use bitcoin::TxMerkleNode;
 use crate::prelude::*;
 use crate::sync::{Arc, Mutex};
 
@@ -121,15 +119,7 @@ fn test_monitor_and_persister_update_fail() {
  assert_eq!(chain_mon.watch_channel(outpoint, new_monitor), ChannelMonitorUpdateStatus::Completed);
  chain_mon
 	};
-	let header = BlockHeader {
- version: 0x20000000,
- prev_blockhash: BlockHash::all_zeros(),
- merkle_root: TxMerkleNode::all_zeros(),
- time: 42,
- bits: 42,
- nonce: 42
-	};
-	chain_mon.chain_monitor.block_connected(&Block { header, txdata: vec![] }, 200);
+	chain_mon.chain_monitor.block_connected(&create_dummy_block(BlockHash::all_zeros(), 42, Vec::new()), 200);
 
 	// Set the persister's return value to be a InProgress.
 	persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);

lightning/src/ln/channelmanager.rs

@@ -9387,10 +9387,7 @@ pub mod bench {
 
  assert_eq!(&tx_broadcaster.txn_broadcasted.lock().unwrap()[..], &[tx.clone()]);
 
- let block = Block {
- header: BlockHeader { version: 0x20000000, prev_blockhash: BestBlock::from_network(network).block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: 42, bits: 42, nonce: 42 },
- txdata: vec![tx],
- };
+ let block = create_dummy_block(BestBlock::from_network(network).block_hash(), 42, vec![tx]);
  Listen::block_connected(&node_a, &block, 1);
  Listen::block_connected(&node_b, &block, 1);
 

lightning/src/ln/functional_test_utils.rs

@@ -85,16 +85,14 @@ pub fn confirm_transactions_at<'a, 'b, 'c, 'd>(node: &'a Node<'b, 'c, 'd>, txn:
 	if conf_height > first_connect_height {
  connect_blocks(node, conf_height - first_connect_height);
 	}
-	let mut block = Block {
- header: BlockHeader { version: 0x20000000, prev_blockhash: node.best_block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: conf_height, bits: 42, nonce: 42 },
- txdata: Vec::new(),
-	};
+	let mut txdata = Vec::new();
 	for _ in 0..*node.network_chan_count.borrow() { // Make sure we don't end up with channels at the same short id by offsetting by chan_count
-block.txdata.push(Transaction { version: 0, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() });
+ txdata.push(Transaction { version: 0, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() });
 	}
 	for tx in txn {
-block.txdata.push((*tx).clone());
+ txdata.push((*tx).clone());
 	}
+	let block = create_dummy_block(node.best_block_hash(), conf_height, txdata);
 	connect_block(node, &block);
 	scid_utils::scid_from_parts(conf_height as u64, block.txdata.len() as u64 - 1, 0).unwrap()
 }
@@ -191,22 +189,31 @@ impl ConnectStyle {
 	}
 }
 
+pub fn create_dummy_header(prev_blockhash: BlockHash, time: u32) -> BlockHeader {
+	BlockHeader {
+ version: 0x2000_0000,
+ prev_blockhash,
+ merkle_root: TxMerkleNode::all_zeros(),
+ time,
+ bits: 42,
+ nonce: 42,
+	}
+}
+
+pub fn create_dummy_block(prev_blockhash: BlockHash, time: u32, txdata: Vec<Transaction>) -> Block {
+	Block { header: create_dummy_header(prev_blockhash, time), txdata }
+}
+
 pub fn connect_blocks<'a, 'b, 'c, 'd>(node: &'a Node<'b, 'c, 'd>, depth: u32) -> BlockHash {
 	let skip_intermediaries = node.connect_style.borrow().skips_blocks();
 
 	let height = node.best_block_info().1 + 1;
-	let mut block = Block {
- header: BlockHeader { version: 0x2000000, prev_blockhash: node.best_block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: height, bits: 42, nonce: 42 },
- txdata: vec![],
-	};
+	let mut block = create_dummy_block(node.best_block_hash(), height, Vec::new());
 	assert!(depth >= 1);
 	for i in 1..depth {
  let prev_blockhash = block.header.block_hash();
  do_connect_block(node, block, skip_intermediaries);
- block = Block {
- header: BlockHeader { version: 0x20000000, prev_blockhash, merkle_root: TxMerkleNode::all_zeros(), time: height + i, bits: 42, nonce: 42 },
- txdata: vec![],
- };
+ block = create_dummy_block(prev_blockhash, height + i, Vec::new());
 	}
 	let hash = block.header.block_hash();
 	do_connect_block(node, block, false);

.gitignore

@@ -10,4 +10,5 @@ Cargo.lock
 lightning/target
 lightning/ldk-net_graph-*.bin
 lightning-custom-message/target
+lightning-transaction-sync/target
 no-std-check/target

fuzz/src/chanmon_consistency.rs

@@ -18,8 +18,6 @@
 //! send-side handling is correct, other peers. We consider it a failure if any action results in a
 //! channel being force-closed.
 
-use bitcoin::TxMerkleNode;
-use bitcoin::blockdata::block::BlockHeader;
 use bitcoin::blockdata::constants::genesis_block;
 use bitcoin::blockdata::transaction::{Transaction, TxOut};
 use bitcoin::blockdata::script::{Builder, Script};
@@ -45,6 +43,7 @@ use lightning::ln::channelmanager::{ChainParameters, ChannelDetails, ChannelMana
 use lightning::ln::channel::FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE;
 use lightning::ln::msgs::{self, CommitmentUpdate, ChannelMessageHandler, DecodeError, UpdateAddHTLC, Init};
 use lightning::ln::script::ShutdownScript;
+use lightning::ln::functional_test_utils::*;
 use lightning::util::enforcing_trait_impls::{EnforcingSigner, EnforcementState};
 use lightning::util::errors::APIError;
 use lightning::util::logger::Logger;
@@ -547,11 +546,11 @@ pub fn do_test<Out: Output>(data: &[u8], underlying_out: Out) {
 	macro_rules! confirm_txn {
  ($node: expr) => { {
  let chain_hash = genesis_block(Network::Bitcoin).block_hash();
- let mut header = BlockHeader { version: 0x20000000, prev_blockhash: chain_hash, merkle_root: TxMerkleNode::all_zeros(), time: 42, bits: 42, nonce: 42 };
+ 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 = BlockHeader { version: 0x20000000, prev_blockhash: header.block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: 42, bits: 42, nonce: 42 };
+ header = create_dummy_header(header.block_hash(), 42);
  }
  $node.best_block_updated(&header, 99);
  } }

fuzz/src/full_stack.rs

@@ -13,8 +13,6 @@
 //! or payments to send/ways to handle events generated.
 //! This test has been very useful, though due to its complexity good starting inputs are critical.
 
-use bitcoin::TxMerkleNode;
-use bitcoin::blockdata::block::BlockHeader;
 use bitcoin::blockdata::constants::genesis_block;
 use bitcoin::blockdata::transaction::{Transaction, TxOut};
 use bitcoin::blockdata::script::{Builder, Script};
@@ -41,14 +39,15 @@ use lightning::ln::channelmanager::{ChainParameters, ChannelDetails, ChannelMana
 use lightning::ln::peer_handler::{MessageHandler,PeerManager,SocketDescriptor,IgnoringMessageHandler};
 use lightning::ln::msgs::{self, DecodeError};
 use lightning::ln::script::ShutdownScript;
+use lightning::ln::functional_test_utils::*;
 use lightning::routing::gossip::{P2PGossipSync, NetworkGraph};
 use lightning::routing::utxo::UtxoLookup;
 use lightning::routing::router::{InFlightHtlcs, PaymentParameters, Route, RouteParameters, Router};
 use lightning::util::config::UserConfig;
 use lightning::util::errors::APIError;
 use lightning::util::enforcing_trait_impls::{EnforcingSigner, EnforcementState};
 use lightning::util::logger::Logger;
-use lightning::util::ser::{Readable, ReadableArgs, Writeable};
+use lightning::util::ser::{ReadableArgs, Writeable};
 
 use crate::utils::test_logger;
 use crate::utils::test_persister::TestPersister;
@@ -228,7 +227,7 @@ impl<'a> MoneyLossDetector<'a> {
  }
 
  self.blocks_connected += 1;
- let header = BlockHeader { version: 0x20000000, prev_blockhash: self.header_hashes[self.height].0, merkle_root: TxMerkleNode::all_zeros(), time: self.blocks_connected, bits: 42, nonce: 42 };
+ let header = create_dummy_header(self.header_hashes[self.height].0, self.blocks_connected);
  self.height += 1;
  self.manager.transactions_confirmed(&header, &txdata, self.height as u32);
  self.manager.best_block_updated(&header, self.height as u32);
@@ -245,7 +244,7 @@ impl<'a> MoneyLossDetector<'a> {
 
 	fn disconnect_block(&mut self) {
  if self.height > 0 && (self.max_height < 6 || self.height >= self.max_height - 6) {
- let header = BlockHeader { version: 0x20000000, prev_blockhash: self.header_hashes[self.height - 1].0, merkle_root: TxMerkleNode::all_zeros(), time: self.header_hashes[self.height].1, bits: 42, nonce: 42 };
+ let header = create_dummy_header(self.header_hashes[self.height - 1].0, self.header_hashes[self.height].1);
  self.manager.block_disconnected(&header, self.height as u32);
  self.monitor.block_disconnected(&header, self.height as u32);
  self.height -= 1;

lightning-background-processor/src/lib.rs

@@ -817,7 +817,6 @@ impl Drop for BackgroundProcessor {
 
 #[cfg(all(feature = "std", test))]
 mod tests {
-	use bitcoin::blockdata::block::BlockHeader;
 	use bitcoin::blockdata::constants::genesis_block;
 	use bitcoin::blockdata::locktime::PackedLockTime;
 	use bitcoin::blockdata::transaction::{Transaction, TxOut};
@@ -833,6 +832,7 @@ mod tests {
 	use lightning::ln::channelmanager;
 	use lightning::ln::channelmanager::{BREAKDOWN_TIMEOUT, ChainParameters, MIN_CLTV_EXPIRY_DELTA, PaymentId};
 	use lightning::ln::features::{ChannelFeatures, NodeFeatures};
+	use lightning::ln::functional_test_utils::*;
 	use lightning::ln::msgs::{ChannelMessageHandler, Init};
 	use lightning::ln::peer_handler::{PeerManager, MessageHandler, SocketDescriptor, IgnoringMessageHandler};
 	use lightning::routing::gossip::{NetworkGraph, NodeId, P2PGossipSync};
@@ -849,8 +849,6 @@ mod tests {
 	use std::sync::{Arc, Mutex};
 	use std::sync::mpsc::SyncSender;
 	use std::time::Duration;
-	use bitcoin::hashes::Hash;
-	use bitcoin::TxMerkleNode;
 	use lightning_rapid_gossip_sync::RapidGossipSync;
 	use super::{BackgroundProcessor, GossipSync, FRESHNESS_TIMER};
 
@@ -1189,7 +1187,7 @@ mod tests {
  for i in 1..=depth {
  let prev_blockhash = node.best_block.block_hash();
  let height = node.best_block.height() + 1;
- let header = BlockHeader { version: 0x20000000, prev_blockhash, merkle_root: TxMerkleNode::all_zeros(), time: height, bits: 42, nonce: 42 };
+ let header = create_dummy_header(prev_blockhash, height);
  let txdata = vec![(0, tx)];
  node.best_block = BestBlock::new(header.block_hash(), height);
  match i {

lightning-block-sync/src/poll.rs

@@ -136,8 +136,11 @@ impl ValidatedBlockHeader {
 
  if let Network::Bitcoin = network {
  if self.height % 2016 == 0 {
- let previous_work = previous_header.header.work();
- if work > (previous_work << 2) || work < (previous_work >> 2) {
+ let target = self.header.target();
+ let previous_target = previous_header.header.target();
+ let min_target = previous_target >> 2;
+ let max_target = previous_target << 2;
+ if target > max_target || target < min_target {
  return Err(BlockSourceError::persistent("invalid difficulty transition"))
  }
  } else if self.header.bits != previous_header.header.bits {

lightning-persister/src/lib.rs

@@ -136,9 +136,8 @@ mod tests {
 	extern crate lightning;
 	extern crate bitcoin;
 	use crate::FilesystemPersister;
-	use bitcoin::blockdata::block::{Block, BlockHeader};
 	use bitcoin::hashes::hex::FromHex;
-	use bitcoin::{Txid, TxMerkleNode};
+	use bitcoin::Txid;
 	use lightning::chain::ChannelMonitorUpdateStatus;
 	use lightning::chain::chainmonitor::Persist;
 	use lightning::chain::channelmonitor::CLOSED_CHANNEL_UPDATE_ID;
@@ -148,7 +147,6 @@ mod tests {
 	use lightning::ln::functional_test_utils::*;
 	use lightning::util::test_utils;
 	use std::fs;
-	use bitcoin::hashes::Hash;
 	#[cfg(target_os = "windows")]
 	use {
  lightning::get_event_msg,
@@ -247,8 +245,7 @@ mod tests {
  let node_txn = nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap();
  assert_eq!(node_txn.len(), 1);
 
- let header = BlockHeader { version: 0x20000000, prev_blockhash: nodes[0].best_block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: 42, bits: 42, nonce: 42 };
- connect_block(&nodes[1], &Block { header, txdata: vec![node_txn[0].clone(), node_txn[0].clone()]});
+ connect_block(&nodes[1], &create_dummy_block(nodes[0].best_block_hash(), 42, vec![node_txn[0].clone(), node_txn[0].clone()]));
  check_closed_broadcast!(nodes[1], true);
  check_closed_event!(nodes[1], 1, ClosureReason::CommitmentTxConfirmed);
  check_added_monitors!(nodes[1], 1);

lightning/src/chain/chainmonitor.rs

@@ -825,8 +825,6 @@ impl<ChannelSigner: WriteableEcdsaChannelSigner, C: Deref, T: Deref, F: Deref, L
 
 #[cfg(test)]
 mod tests {
-	use bitcoin::{BlockHeader, TxMerkleNode};
-	use bitcoin::hashes::Hash;
 	use crate::{check_added_monitors, check_closed_broadcast, check_closed_event};
 	use crate::{expect_payment_sent, expect_payment_claimed, expect_payment_sent_without_paths, expect_payment_path_successful, get_event_msg};
 	use crate::{get_htlc_update_msgs, get_local_commitment_txn, get_revoke_commit_msgs, get_route_and_payment_hash, unwrap_send_err};
@@ -972,10 +970,7 @@ mod tests {
 
  // Connect B's commitment transaction, but only to the ChainMonitor/ChannelMonitor. The
  // channel is now closed, but the ChannelManager doesn't know that yet.
- let new_header = BlockHeader {
- version: 2, time: 0, bits: 0, nonce: 0,
- prev_blockhash: nodes[0].best_block_info().0,
- merkle_root: TxMerkleNode::all_zeros() };
+ let new_header = create_dummy_header(nodes[0].best_block_info().0, 0);
  nodes[0].chain_monitor.chain_monitor.transactions_confirmed(&new_header,
  &[(0, &remote_txn[0]), (1, &remote_txn[1])], nodes[0].best_block_info().1 + 1);
  assert!(nodes[0].chain_monitor.release_pending_monitor_events().is_empty());
@@ -999,10 +994,7 @@ mod tests {
 
  if block_timeout {
  // After three blocks, pending MontiorEvents should be released either way.
- let latest_header = BlockHeader {
- version: 2, time: 0, bits: 0, nonce: 0,
- prev_blockhash: nodes[0].best_block_info().0,
- merkle_root: TxMerkleNode::all_zeros() };
+ let latest_header = create_dummy_header(nodes[0].best_block_info().0, 0);
  nodes[0].chain_monitor.chain_monitor.best_block_updated(&latest_header, nodes[0].best_block_info().1 + LATENCY_GRACE_PERIOD_BLOCKS);
  } else {
  let persistences = chanmon_cfgs[0].persister.chain_sync_monitor_persistences.lock().unwrap().clone();

lightning/src/chain/channelmonitor.rs

@@ -4084,7 +4084,6 @@ impl<'a, 'b, ES: EntropySource, SP: SignerProvider> ReadableArgs<(&'a ES, &'b SP
 
 #[cfg(test)]
 mod tests {
-	use bitcoin::blockdata::block::BlockHeader;
 	use bitcoin::blockdata::script::{Script, Builder};
 	use bitcoin::blockdata::opcodes;
 	use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, EcdsaSighashType};
@@ -4121,7 +4120,7 @@ mod tests {
 	use crate::util::ser::{ReadableArgs, Writeable};
 	use crate::sync::{Arc, Mutex};
 	use crate::io;
-	use bitcoin::{PackedLockTime, Sequence, TxMerkleNode, Witness};
+	use bitcoin::{PackedLockTime, Sequence, Witness};
 	use crate::prelude::*;
 
 	fn do_test_funding_spend_refuses_updates(use_local_txn: bool) {
@@ -4160,10 +4159,7 @@ mod tests {
 
  // Connect a commitment transaction, but only to the ChainMonitor/ChannelMonitor. The
  // channel is now closed, but the ChannelManager doesn't know that yet.
- let new_header = BlockHeader {
- version: 2, time: 0, bits: 0, nonce: 0,
- prev_blockhash: nodes[0].best_block_info().0,
- merkle_root: TxMerkleNode::all_zeros() };
+ let new_header = create_dummy_header(nodes[0].best_block_info().0, 0);
  let conf_height = nodes[0].best_block_info().1 + 1;
  nodes[1].chain_monitor.chain_monitor.transactions_confirmed(&new_header,
  &[(0, broadcast_tx)], conf_height);

lightning/src/ln/chanmon_update_fail_tests.rs

@@ -12,7 +12,6 @@
 //! There are a bunch of these as their handling is relatively error-prone so they are split out
 //! here. See also the chanmon_fail_consistency fuzz test.
 
-use bitcoin::blockdata::block::{Block, BlockHeader};
 use bitcoin::blockdata::constants::genesis_block;
 use bitcoin::hash_types::BlockHash;
 use bitcoin::network::constants::Network;
@@ -35,7 +34,6 @@ use crate::util::test_utils;
 
 use crate::io;
 use bitcoin::hashes::Hash;
-use bitcoin::TxMerkleNode;
 use crate::prelude::*;
 use crate::sync::{Arc, Mutex};
 
@@ -121,15 +119,7 @@ fn test_monitor_and_persister_update_fail() {
  assert_eq!(chain_mon.watch_channel(outpoint, new_monitor), ChannelMonitorUpdateStatus::Completed);
  chain_mon
 	};
-	let header = BlockHeader {
- version: 0x20000000,
- prev_blockhash: BlockHash::all_zeros(),
- merkle_root: TxMerkleNode::all_zeros(),
- time: 42,
- bits: 42,
- nonce: 42
-	};
-	chain_mon.chain_monitor.block_connected(&Block { header, txdata: vec![] }, 200);
+	chain_mon.chain_monitor.block_connected(&create_dummy_block(BlockHash::all_zeros(), 42, Vec::new()), 200);
 
 	// Set the persister's return value to be a InProgress.
 	persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);

lightning/src/ln/channelmanager.rs

@@ -9387,10 +9387,7 @@ pub mod bench {
 
  assert_eq!(&tx_broadcaster.txn_broadcasted.lock().unwrap()[..], &[tx.clone()]);
 
- let block = Block {
- header: BlockHeader { version: 0x20000000, prev_blockhash: BestBlock::from_network(network).block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: 42, bits: 42, nonce: 42 },
- txdata: vec![tx],
- };
+ let block = create_dummy_block(BestBlock::from_network(network).block_hash(), 42, vec![tx]);
  Listen::block_connected(&node_a, &block, 1);
  Listen::block_connected(&node_b, &block, 1);
 

lightning/src/ln/functional_test_utils.rs

@@ -85,16 +85,14 @@ pub fn confirm_transactions_at<'a, 'b, 'c, 'd>(node: &'a Node<'b, 'c, 'd>, txn:
 	if conf_height > first_connect_height {
  connect_blocks(node, conf_height - first_connect_height);
 	}
-	let mut block = Block {
- header: BlockHeader { version: 0x20000000, prev_blockhash: node.best_block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: conf_height, bits: 42, nonce: 42 },
- txdata: Vec::new(),
-	};
+	let mut txdata = Vec::new();
 	for _ in 0..*node.network_chan_count.borrow() { // Make sure we don't end up with channels at the same short id by offsetting by chan_count
-block.txdata.push(Transaction { version: 0, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() });
+ txdata.push(Transaction { version: 0, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() });
 	}
 	for tx in txn {
-block.txdata.push((*tx).clone());
+ txdata.push((*tx).clone());
 	}
+	let block = create_dummy_block(node.best_block_hash(), conf_height, txdata);
 	connect_block(node, &block);
 	scid_utils::scid_from_parts(conf_height as u64, block.txdata.len() as u64 - 1, 0).unwrap()
 }
@@ -191,22 +189,31 @@ impl ConnectStyle {
 	}
 }
 
+pub fn create_dummy_header(prev_blockhash: BlockHash, time: u32) -> BlockHeader {
+	BlockHeader {
+ version: 0x2000_0000,
+ prev_blockhash,
+ merkle_root: TxMerkleNode::all_zeros(),
+ time,
+ bits: 42,
+ nonce: 42,
+	}
+}
+
+pub fn create_dummy_block(prev_blockhash: BlockHash, time: u32, txdata: Vec<Transaction>) -> Block {
+	Block { header: create_dummy_header(prev_blockhash, time), txdata }
+}
+
 pub fn connect_blocks<'a, 'b, 'c, 'd>(node: &'a Node<'b, 'c, 'd>, depth: u32) -> BlockHash {
 	let skip_intermediaries = node.connect_style.borrow().skips_blocks();
 
 	let height = node.best_block_info().1 + 1;
-	let mut block = Block {
- header: BlockHeader { version: 0x2000000, prev_blockhash: node.best_block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: height, bits: 42, nonce: 42 },
- txdata: vec![],
-	};
+	let mut block = create_dummy_block(node.best_block_hash(), height, Vec::new());
 	assert!(depth >= 1);
 	for i in 1..depth {
  let prev_blockhash = block.header.block_hash();
  do_connect_block(node, block, skip_intermediaries);
- block = Block {
- header: BlockHeader { version: 0x20000000, prev_blockhash, merkle_root: TxMerkleNode::all_zeros(), time: height + i, bits: 42, nonce: 42 },
- txdata: vec![],
- };
+ block = create_dummy_block(prev_blockhash, height + i, Vec::new());
 	}
 	let hash = block.header.block_hash();
 	do_connect_block(node, block, false);

.gitignore

@@ -10,4 +10,5 @@ Cargo.lock
 lightning/target
 lightning/ldk-net_graph-*.bin
 lightning-custom-message/target
+lightning-transaction-sync/target
 no-std-check/target

fuzz/src/chanmon_consistency.rs

@@ -18,8 +18,6 @@
 //! send-side handling is correct, other peers. We consider it a failure if any action results in a
 //! channel being force-closed.
 
-use bitcoin::TxMerkleNode;
-use bitcoin::blockdata::block::BlockHeader;
 use bitcoin::blockdata::constants::genesis_block;
 use bitcoin::blockdata::transaction::{Transaction, TxOut};
 use bitcoin::blockdata::script::{Builder, Script};
@@ -45,6 +43,7 @@ use lightning::ln::channelmanager::{ChainParameters, ChannelDetails, ChannelMana
 use lightning::ln::channel::FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE;
 use lightning::ln::msgs::{self, CommitmentUpdate, ChannelMessageHandler, DecodeError, UpdateAddHTLC, Init};
 use lightning::ln::script::ShutdownScript;
+use lightning::ln::functional_test_utils::*;
 use lightning::util::enforcing_trait_impls::{EnforcingSigner, EnforcementState};
 use lightning::util::errors::APIError;
 use lightning::util::logger::Logger;
@@ -547,11 +546,11 @@ pub fn do_test<Out: Output>(data: &[u8], underlying_out: Out) {
 	macro_rules! confirm_txn {
  ($node: expr) => { {
  let chain_hash = genesis_block(Network::Bitcoin).block_hash();
- let mut header = BlockHeader { version: 0x20000000, prev_blockhash: chain_hash, merkle_root: TxMerkleNode::all_zeros(), time: 42, bits: 42, nonce: 42 };
+ 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 = BlockHeader { version: 0x20000000, prev_blockhash: header.block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: 42, bits: 42, nonce: 42 };
+ header = create_dummy_header(header.block_hash(), 42);
  }
  $node.best_block_updated(&header, 99);
  } }

fuzz/src/full_stack.rs

@@ -13,8 +13,6 @@
 //! or payments to send/ways to handle events generated.
 //! This test has been very useful, though due to its complexity good starting inputs are critical.
 
-use bitcoin::TxMerkleNode;
-use bitcoin::blockdata::block::BlockHeader;
 use bitcoin::blockdata::constants::genesis_block;
 use bitcoin::blockdata::transaction::{Transaction, TxOut};
 use bitcoin::blockdata::script::{Builder, Script};
@@ -41,14 +39,15 @@ use lightning::ln::channelmanager::{ChainParameters, ChannelDetails, ChannelMana
 use lightning::ln::peer_handler::{MessageHandler,PeerManager,SocketDescriptor,IgnoringMessageHandler};
 use lightning::ln::msgs::{self, DecodeError};
 use lightning::ln::script::ShutdownScript;
+use lightning::ln::functional_test_utils::*;
 use lightning::routing::gossip::{P2PGossipSync, NetworkGraph};
 use lightning::routing::utxo::UtxoLookup;
 use lightning::routing::router::{InFlightHtlcs, PaymentParameters, Route, RouteParameters, Router};
 use lightning::util::config::UserConfig;
 use lightning::util::errors::APIError;
 use lightning::util::enforcing_trait_impls::{EnforcingSigner, EnforcementState};
 use lightning::util::logger::Logger;
-use lightning::util::ser::{Readable, ReadableArgs, Writeable};
+use lightning::util::ser::{ReadableArgs, Writeable};
 
 use crate::utils::test_logger;
 use crate::utils::test_persister::TestPersister;
@@ -228,7 +227,7 @@ impl<'a> MoneyLossDetector<'a> {
  }
 
  self.blocks_connected += 1;
- let header = BlockHeader { version: 0x20000000, prev_blockhash: self.header_hashes[self.height].0, merkle_root: TxMerkleNode::all_zeros(), time: self.blocks_connected, bits: 42, nonce: 42 };
+ let header = create_dummy_header(self.header_hashes[self.height].0, self.blocks_connected);
  self.height += 1;
  self.manager.transactions_confirmed(&header, &txdata, self.height as u32);
  self.manager.best_block_updated(&header, self.height as u32);
@@ -245,7 +244,7 @@ impl<'a> MoneyLossDetector<'a> {
 
 	fn disconnect_block(&mut self) {
  if self.height > 0 && (self.max_height < 6 || self.height >= self.max_height - 6) {
- let header = BlockHeader { version: 0x20000000, prev_blockhash: self.header_hashes[self.height - 1].0, merkle_root: TxMerkleNode::all_zeros(), time: self.header_hashes[self.height].1, bits: 42, nonce: 42 };
+ let header = create_dummy_header(self.header_hashes[self.height - 1].0, self.header_hashes[self.height].1);
  self.manager.block_disconnected(&header, self.height as u32);
  self.monitor.block_disconnected(&header, self.height as u32);
  self.height -= 1;

lightning-background-processor/src/lib.rs

@@ -817,7 +817,6 @@ impl Drop for BackgroundProcessor {
 
 #[cfg(all(feature = "std", test))]
 mod tests {
-	use bitcoin::blockdata::block::BlockHeader;
 	use bitcoin::blockdata::constants::genesis_block;
 	use bitcoin::blockdata::locktime::PackedLockTime;
 	use bitcoin::blockdata::transaction::{Transaction, TxOut};
@@ -833,6 +832,7 @@ mod tests {
 	use lightning::ln::channelmanager;
 	use lightning::ln::channelmanager::{BREAKDOWN_TIMEOUT, ChainParameters, MIN_CLTV_EXPIRY_DELTA, PaymentId};
 	use lightning::ln::features::{ChannelFeatures, NodeFeatures};
+	use lightning::ln::functional_test_utils::*;
 	use lightning::ln::msgs::{ChannelMessageHandler, Init};
 	use lightning::ln::peer_handler::{PeerManager, MessageHandler, SocketDescriptor, IgnoringMessageHandler};
 	use lightning::routing::gossip::{NetworkGraph, NodeId, P2PGossipSync};
@@ -849,8 +849,6 @@ mod tests {
 	use std::sync::{Arc, Mutex};
 	use std::sync::mpsc::SyncSender;
 	use std::time::Duration;
-	use bitcoin::hashes::Hash;
-	use bitcoin::TxMerkleNode;
 	use lightning_rapid_gossip_sync::RapidGossipSync;
 	use super::{BackgroundProcessor, GossipSync, FRESHNESS_TIMER};
 
@@ -1189,7 +1187,7 @@ mod tests {
  for i in 1..=depth {
  let prev_blockhash = node.best_block.block_hash();
  let height = node.best_block.height() + 1;
- let header = BlockHeader { version: 0x20000000, prev_blockhash, merkle_root: TxMerkleNode::all_zeros(), time: height, bits: 42, nonce: 42 };
+ let header = create_dummy_header(prev_blockhash, height);
  let txdata = vec![(0, tx)];
  node.best_block = BestBlock::new(header.block_hash(), height);
  match i {

lightning-block-sync/src/poll.rs

@@ -136,8 +136,11 @@ impl ValidatedBlockHeader {
 
  if let Network::Bitcoin = network {
  if self.height % 2016 == 0 {
- let previous_work = previous_header.header.work();
- if work > (previous_work << 2) || work < (previous_work >> 2) {
+ let target = self.header.target();
+ let previous_target = previous_header.header.target();
+ let min_target = previous_target >> 2;
+ let max_target = previous_target << 2;
+ if target > max_target || target < min_target {
  return Err(BlockSourceError::persistent("invalid difficulty transition"))
  }
  } else if self.header.bits != previous_header.header.bits {

lightning-persister/src/lib.rs

@@ -136,9 +136,8 @@ mod tests {
 	extern crate lightning;
 	extern crate bitcoin;
 	use crate::FilesystemPersister;
-	use bitcoin::blockdata::block::{Block, BlockHeader};
 	use bitcoin::hashes::hex::FromHex;
-	use bitcoin::{Txid, TxMerkleNode};
+	use bitcoin::Txid;
 	use lightning::chain::ChannelMonitorUpdateStatus;
 	use lightning::chain::chainmonitor::Persist;
 	use lightning::chain::channelmonitor::CLOSED_CHANNEL_UPDATE_ID;
@@ -148,7 +147,6 @@ mod tests {
 	use lightning::ln::functional_test_utils::*;
 	use lightning::util::test_utils;
 	use std::fs;
-	use bitcoin::hashes::Hash;
 	#[cfg(target_os = "windows")]
 	use {
  lightning::get_event_msg,
@@ -247,8 +245,7 @@ mod tests {
  let node_txn = nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap();
  assert_eq!(node_txn.len(), 1);
 
- let header = BlockHeader { version: 0x20000000, prev_blockhash: nodes[0].best_block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: 42, bits: 42, nonce: 42 };
- connect_block(&nodes[1], &Block { header, txdata: vec![node_txn[0].clone(), node_txn[0].clone()]});
+ connect_block(&nodes[1], &create_dummy_block(nodes[0].best_block_hash(), 42, vec![node_txn[0].clone(), node_txn[0].clone()]));
  check_closed_broadcast!(nodes[1], true);
  check_closed_event!(nodes[1], 1, ClosureReason::CommitmentTxConfirmed);
  check_added_monitors!(nodes[1], 1);

lightning/src/chain/chainmonitor.rs

@@ -825,8 +825,6 @@ impl<ChannelSigner: WriteableEcdsaChannelSigner, C: Deref, T: Deref, F: Deref, L
 
 #[cfg(test)]
 mod tests {
-	use bitcoin::{BlockHeader, TxMerkleNode};
-	use bitcoin::hashes::Hash;
 	use crate::{check_added_monitors, check_closed_broadcast, check_closed_event};
 	use crate::{expect_payment_sent, expect_payment_claimed, expect_payment_sent_without_paths, expect_payment_path_successful, get_event_msg};
 	use crate::{get_htlc_update_msgs, get_local_commitment_txn, get_revoke_commit_msgs, get_route_and_payment_hash, unwrap_send_err};
@@ -972,10 +970,7 @@ mod tests {
 
  // Connect B's commitment transaction, but only to the ChainMonitor/ChannelMonitor. The
  // channel is now closed, but the ChannelManager doesn't know that yet.
- let new_header = BlockHeader {
- version: 2, time: 0, bits: 0, nonce: 0,
- prev_blockhash: nodes[0].best_block_info().0,
- merkle_root: TxMerkleNode::all_zeros() };
+ let new_header = create_dummy_header(nodes[0].best_block_info().0, 0);
  nodes[0].chain_monitor.chain_monitor.transactions_confirmed(&new_header,
  &[(0, &remote_txn[0]), (1, &remote_txn[1])], nodes[0].best_block_info().1 + 1);
  assert!(nodes[0].chain_monitor.release_pending_monitor_events().is_empty());
@@ -999,10 +994,7 @@ mod tests {
 
  if block_timeout {
  // After three blocks, pending MontiorEvents should be released either way.
- let latest_header = BlockHeader {
- version: 2, time: 0, bits: 0, nonce: 0,
- prev_blockhash: nodes[0].best_block_info().0,
- merkle_root: TxMerkleNode::all_zeros() };
+ let latest_header = create_dummy_header(nodes[0].best_block_info().0, 0);
  nodes[0].chain_monitor.chain_monitor.best_block_updated(&latest_header, nodes[0].best_block_info().1 + LATENCY_GRACE_PERIOD_BLOCKS);
  } else {
  let persistences = chanmon_cfgs[0].persister.chain_sync_monitor_persistences.lock().unwrap().clone();

lightning/src/chain/channelmonitor.rs

@@ -4084,7 +4084,6 @@ impl<'a, 'b, ES: EntropySource, SP: SignerProvider> ReadableArgs<(&'a ES, &'b SP
 
 #[cfg(test)]
 mod tests {
-	use bitcoin::blockdata::block::BlockHeader;
 	use bitcoin::blockdata::script::{Script, Builder};
 	use bitcoin::blockdata::opcodes;
 	use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, EcdsaSighashType};
@@ -4121,7 +4120,7 @@ mod tests {
 	use crate::util::ser::{ReadableArgs, Writeable};
 	use crate::sync::{Arc, Mutex};
 	use crate::io;
-	use bitcoin::{PackedLockTime, Sequence, TxMerkleNode, Witness};
+	use bitcoin::{PackedLockTime, Sequence, Witness};
 	use crate::prelude::*;
 
 	fn do_test_funding_spend_refuses_updates(use_local_txn: bool) {
@@ -4160,10 +4159,7 @@ mod tests {
 
  // Connect a commitment transaction, but only to the ChainMonitor/ChannelMonitor. The
  // channel is now closed, but the ChannelManager doesn't know that yet.
- let new_header = BlockHeader {
- version: 2, time: 0, bits: 0, nonce: 0,
- prev_blockhash: nodes[0].best_block_info().0,
- merkle_root: TxMerkleNode::all_zeros() };
+ let new_header = create_dummy_header(nodes[0].best_block_info().0, 0);
  let conf_height = nodes[0].best_block_info().1 + 1;
  nodes[1].chain_monitor.chain_monitor.transactions_confirmed(&new_header,
  &[(0, broadcast_tx)], conf_height);

lightning/src/ln/chanmon_update_fail_tests.rs

@@ -12,7 +12,6 @@
 //! There are a bunch of these as their handling is relatively error-prone so they are split out
 //! here. See also the chanmon_fail_consistency fuzz test.
 
-use bitcoin::blockdata::block::{Block, BlockHeader};
 use bitcoin::blockdata::constants::genesis_block;
 use bitcoin::hash_types::BlockHash;
 use bitcoin::network::constants::Network;
@@ -35,7 +34,6 @@ use crate::util::test_utils;
 
 use crate::io;
 use bitcoin::hashes::Hash;
-use bitcoin::TxMerkleNode;
 use crate::prelude::*;
 use crate::sync::{Arc, Mutex};
 
@@ -121,15 +119,7 @@ fn test_monitor_and_persister_update_fail() {
  assert_eq!(chain_mon.watch_channel(outpoint, new_monitor), ChannelMonitorUpdateStatus::Completed);
  chain_mon
 	};
-	let header = BlockHeader {
- version: 0x20000000,
- prev_blockhash: BlockHash::all_zeros(),
- merkle_root: TxMerkleNode::all_zeros(),
- time: 42,
- bits: 42,
- nonce: 42
-	};
-	chain_mon.chain_monitor.block_connected(&Block { header, txdata: vec![] }, 200);
+	chain_mon.chain_monitor.block_connected(&create_dummy_block(BlockHash::all_zeros(), 42, Vec::new()), 200);
 
 	// Set the persister's return value to be a InProgress.
 	persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);

lightning/src/ln/channelmanager.rs

@@ -9387,10 +9387,7 @@ pub mod bench {
 
  assert_eq!(&tx_broadcaster.txn_broadcasted.lock().unwrap()[..], &[tx.clone()]);
 
- let block = Block {
- header: BlockHeader { version: 0x20000000, prev_blockhash: BestBlock::from_network(network).block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: 42, bits: 42, nonce: 42 },
- txdata: vec![tx],
- };
+ let block = create_dummy_block(BestBlock::from_network(network).block_hash(), 42, vec![tx]);
  Listen::block_connected(&node_a, &block, 1);
  Listen::block_connected(&node_b, &block, 1);
 

lightning/src/ln/functional_test_utils.rs

@@ -85,16 +85,14 @@ pub fn confirm_transactions_at<'a, 'b, 'c, 'd>(node: &'a Node<'b, 'c, 'd>, txn:
 	if conf_height > first_connect_height {
  connect_blocks(node, conf_height - first_connect_height);
 	}
-	let mut block = Block {
- header: BlockHeader { version: 0x20000000, prev_blockhash: node.best_block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: conf_height, bits: 42, nonce: 42 },
- txdata: Vec::new(),
-	};
+	let mut txdata = Vec::new();
 	for _ in 0..*node.network_chan_count.borrow() { // Make sure we don't end up with channels at the same short id by offsetting by chan_count
-block.txdata.push(Transaction { version: 0, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() });
+ txdata.push(Transaction { version: 0, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() });
 	}
 	for tx in txn {
-block.txdata.push((*tx).clone());
+ txdata.push((*tx).clone());
 	}
+	let block = create_dummy_block(node.best_block_hash(), conf_height, txdata);
 	connect_block(node, &block);
 	scid_utils::scid_from_parts(conf_height as u64, block.txdata.len() as u64 - 1, 0).unwrap()
 }
@@ -191,22 +189,31 @@ impl ConnectStyle {
 	}
 }
 
+pub fn create_dummy_header(prev_blockhash: BlockHash, time: u32) -> BlockHeader {
+	BlockHeader {
+ version: 0x2000_0000,
+ prev_blockhash,
+ merkle_root: TxMerkleNode::all_zeros(),
+ time,
+ bits: 42,
+ nonce: 42,
+	}
+}
+
+pub fn create_dummy_block(prev_blockhash: BlockHash, time: u32, txdata: Vec<Transaction>) -> Block {
+	Block { header: create_dummy_header(prev_blockhash, time), txdata }
+}
+
 pub fn connect_blocks<'a, 'b, 'c, 'd>(node: &'a Node<'b, 'c, 'd>, depth: u32) -> BlockHash {
 	let skip_intermediaries = node.connect_style.borrow().skips_blocks();
 
 	let height = node.best_block_info().1 + 1;
-	let mut block = Block {
- header: BlockHeader { version: 0x2000000, prev_blockhash: node.best_block_hash(), merkle_root: TxMerkleNode::all_zeros(), time: height, bits: 42, nonce: 42 },
- txdata: vec![],
-	};
+	let mut block = create_dummy_block(node.best_block_hash(), height, Vec::new());
 	assert!(depth >= 1);
 	for i in 1..depth {
  let prev_blockhash = block.header.block_hash();
  do_connect_block(node, block, skip_intermediaries);
- block = Block {
- header: BlockHeader { version: 0x20000000, prev_blockhash, merkle_root: TxMerkleNode::all_zeros(), time: height + i, bits: 42, nonce: 42 },
- txdata: vec![],
- };
+ block = create_dummy_block(prev_blockhash, height + i, Vec::new());
 	}
 	let hash = block.header.block_hash();
 	do_connect_block(node, block, false);