X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning-block-sync%2Fsrc%2Fpoll.rs;h=dcc19a4969dd3eab863c1216b17d434b93f54849;hb=2f734f97550014e5424e55523ed46d76b94b737d;hp=6e30d2e86d20d268529bd37d942492db810d84b6;hpb=e0b9b748d63698908266412a8817cc848bc0d18f;p=rust-lightning

diff --git a/lightning-block-sync/src/poll.rs b/lightning-block-sync/src/poll.rs
index 6e30d2e8..dcc19a49 100644
--- a/lightning-block-sync/src/poll.rs
+++ b/lightning-block-sync/src/poll.rs
@@ -1,10 +1,10 @@
 //! Adapters that make one or more [`BlockSource`]s simpler to poll for new chain tip transitions.
 
-use crate::{AsyncBlockSourceResult, BlockHeaderData, BlockSource, BlockSourceError, BlockSourceResult};
+use crate::{AsyncBlockSourceResult, BlockData, BlockHeaderData, BlockSource, BlockSourceError, BlockSourceResult};
 
-use bitcoin::blockdata::block::Block;
 use bitcoin::hash_types::BlockHash;
 use bitcoin::network::constants::Network;
+use lightning::chain::BestBlock;
 
 use std::ops::Deref;
 
@@ -30,7 +30,7 @@ pub trait Poll {
 }
 
 /// A chain tip relative to another chain tip in terms of block hash and chainwork.
-#[derive(Clone, Debug, PartialEq)]
+#[derive(Clone, Debug, PartialEq, Eq)]
 pub enum ChainTip {
 	/// A chain tip with the same hash as another chain's tip.
 	Common,
@@ -59,12 +59,11 @@ impl Validate for BlockHeaderData {
 	type T = ValidatedBlockHeader;
 
 	fn validate(self, block_hash: BlockHash) -> BlockSourceResult<Self::T> {
-		self.header
-			.validate_pow(&self.header.target())
-			.or_else(|e| Err(BlockSourceError::persistent(e)))?;
+		let pow_valid_block_hash = self.header
+			.validate_pow(self.header.target())
+			.map_err(BlockSourceError::persistent)?;
 
-		// TODO: Use the result of validate_pow instead of recomputing the block hash once upstream.
-		if self.header.block_hash() != block_hash {
+		if pow_valid_block_hash != block_hash {
 			return Err(BlockSourceError::persistent("invalid block hash"));
 		}
 
@@ -72,25 +71,31 @@ impl Validate for BlockHeaderData {
 	}
 }
 
-impl Validate for Block {
+impl Validate for BlockData {
 	type T = ValidatedBlock;
 
 	fn validate(self, block_hash: BlockHash) -> BlockSourceResult<Self::T> {
-		self.header
-			.validate_pow(&self.header.target())
-			.or_else(|e| Err(BlockSourceError::persistent(e)))?;
+		let header = match &self {
+			BlockData::FullBlock(block) => &block.header,
+			BlockData::HeaderOnly(header) => header,
+		};
 
-		// TODO: Use the result of validate_pow instead of recomputing the block hash once upstream.
-		if self.block_hash() != block_hash {
+		let pow_valid_block_hash = header
+			.validate_pow(header.target())
+			.map_err(BlockSourceError::persistent)?;
+
+		if pow_valid_block_hash != block_hash {
 			return Err(BlockSourceError::persistent("invalid block hash"));
 		}
 
-		if !self.check_merkle_root() {
-			return Err(BlockSourceError::persistent("invalid merkle root"));
-		}
+		if let BlockData::FullBlock(block) = &self {
+			if !block.check_merkle_root() {
+				return Err(BlockSourceError::persistent("invalid merkle root"));
+			}
 
-		if !self.check_witness_commitment() {
-			return Err(BlockSourceError::persistent("invalid witness commitment"));
+			if !block.check_witness_commitment() {
+				return Err(BlockSourceError::persistent("invalid witness commitment"));
+			}
 		}
 
 		Ok(ValidatedBlock { block_hash, inner: self })
@@ -98,7 +103,7 @@ impl Validate for Block {
 }
 
 /// A block header with validated proof of work and corresponding block hash.
-#[derive(Clone, Copy, Debug, PartialEq)]
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
 pub struct ValidatedBlockHeader {
 	pub(crate) block_hash: BlockHash,
 	inner: BlockHeaderData,
@@ -131,8 +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.min_difficulty_transition_threshold();
+				let max_target = previous_target.max_difficulty_transition_threshold();
+				if target > max_target || target < min_target {
 					return Err(BlockSourceError::persistent("invalid difficulty transition"))
 				}
 			} else if self.header.bits != previous_header.header.bits {
@@ -142,16 +150,29 @@ impl ValidatedBlockHeader {
 
 		Ok(())
 	}
+
+    /// Returns the [`BestBlock`] corresponding to this validated block header, which can be passed
+    /// into [`ChannelManager::new`] as part of its [`ChainParameters`]. Useful for ensuring that
+    /// the [`SpvClient`] and [`ChannelManager`] are initialized to the same block during a fresh
+    /// start.
+    ///
+    /// [`SpvClient`]: crate::SpvClient
+    /// [`ChainParameters`]: lightning::ln::channelmanager::ChainParameters
+    /// [`ChannelManager`]: lightning::ln::channelmanager::ChannelManager
+    /// [`ChannelManager::new`]: lightning::ln::channelmanager::ChannelManager::new
+    pub fn to_best_block(&self) -> BestBlock {
+        BestBlock::new(self.block_hash, self.inner.height)
+    }
 }
 
 /// A block with validated data against its transaction list and corresponding block hash.
 pub struct ValidatedBlock {
 	pub(crate) block_hash: BlockHash,
-	inner: Block,
+	inner: BlockData,
 }
 
 impl std::ops::Deref for ValidatedBlock {
-	type Target = Block;
+	type Target = BlockData;
 
 	fn deref(&self) -> &Self::Target {
 		&self.inner
@@ -163,7 +184,7 @@ mod sealed {
 	pub trait Validate {}
 
 	impl Validate for crate::BlockHeaderData {}
-	impl Validate for bitcoin::blockdata::block::Block {}
+	impl Validate for crate::BlockData {}
 }
 
 /// The canonical `Poll` implementation used for a single `BlockSource`.
@@ -241,7 +262,6 @@ mod tests {
 	use crate::*;
 	use crate::test_utils::Blockchain;
 	use super::*;
-	use bitcoin::util::uint::Uint256;
 
 	#[tokio::test]
 	async fn poll_empty_chain() {
@@ -281,7 +301,7 @@ mod tests {
 
 		// Invalidate the tip by changing its target.
 		chain.blocks.last_mut().unwrap().header.bits =
-			BlockHeader::compact_target_from_u256(&Uint256::from_be_bytes([0; 32]));
+			bitcoin::Target::from_be_bytes([0x01; 32]).to_compact_lossy();
 
 		let poller = ChainPoller::new(&chain, Network::Bitcoin);
 		match poller.poll_chain_tip(best_known_chain_tip).await {