Block header needs its own deserialization. Fixed pow verify to use the block target.

core/src/core/block.rs

@@ -64,8 +64,7 @@ impl Default for BlockHeader {
 	}
 }
 
-// Only Writeable implementation is required for hashing, which is part of
-// core. Readable is in the ser package.
+/// Serialization of a block header
 impl Writeable for BlockHeader {
 	fn write(&self, writer: &mut Writer) -> Result<(), ser::Error> {
 		ser_multiwrite!(writer,
@@ -88,6 +87,37 @@ impl Writeable for BlockHeader {
 	}
 }
 
+/// Deserialization of a block header
+impl Readable<BlockHeader> for BlockHeader {
+	fn read(reader: &mut Reader) -> Result<BlockHeader, ser::Error> {
+		let (height, previous, timestamp, cuckoo_len) =
+			ser_multiread!(reader, read_u64, read_32_bytes, read_i64, read_u8);
+		let target = try!(Target::read(reader));
+		let (utxo_merkle, tx_merkle, nonce) =
+			ser_multiread!(reader, read_32_bytes, read_32_bytes, read_u64);
+
+		// cuckoo cycle of 42 nodes
+		let mut pow = [0; PROOFSIZE];
+		for n in 0..PROOFSIZE {
+			pow[n] = try!(reader.read_u32());
+		}
+    Ok(BlockHeader {
+      height: height,
+      previous: Hash::from_vec(previous),
+      timestamp: time::at_utc(time::Timespec {
+        sec: timestamp,
+        nsec: 0,
+      }),
+      cuckoo_len: cuckoo_len,
+      target: target,
+      utxo_merkle: Hash::from_vec(utxo_merkle),
+      tx_merkle: Hash::from_vec(tx_merkle),
+      pow: Proof(pow),
+      nonce: nonce,
+    })
+  }
+}
+
 /// A block as expressed in the MimbleWimble protocol. The reward is
 /// non-explicit, assumed to be deductible from block height (similar to
 /// bitcoin's schedule) and expressed as a global transaction fee (added v.H),
@@ -127,24 +157,14 @@ impl Writeable for Block {
 /// from a binary stream.
 impl Readable<Block> for Block {
 	fn read(reader: &mut Reader) -> Result<Block, ser::Error> {
-		let (height, previous, timestamp, cuckoo_len) =
-			ser_multiread!(reader, read_u64, read_32_bytes, read_i64, read_u8);
-		let target = try!(Target::read(reader));
-		let (utxo_merkle, tx_merkle, nonce) =
-			ser_multiread!(reader, read_32_bytes, read_32_bytes, read_u64);
+    let header = try!(BlockHeader::read(reader));
 
-		// cuckoo cycle of 42 nodes
-		let mut pow = [0; PROOFSIZE];
-		for n in 0..PROOFSIZE {
-			pow[n] = try!(reader.read_u32());
-		}
-
-		let (td, input_len, output_len, proof_len) =
-			ser_multiread!(reader, read_u64, read_u64, read_u64, read_u64);
+		let (input_len, output_len, proof_len) =
+			ser_multiread!(reader, read_u64, read_u64, read_u64);
 
 		if input_len > MAX_IN_OUT_LEN || output_len > MAX_IN_OUT_LEN || proof_len > MAX_IN_OUT_LEN {
-			return Err(ser::Error::TooLargeReadErr("Too many inputs, outputs or proofs."
-				.to_string()));
+			return Err(ser::Error::TooLargeReadErr(
+          "Too many inputs, outputs or proofs.".to_string()));
 		}
 
 		let inputs = try!((0..input_len).map(|_| Input::read(reader)).collect());
@@ -152,20 +172,7 @@ impl Readable<Block> for Block {
 		let proofs = try!((0..proof_len).map(|_| TxProof::read(reader)).collect());
 
 		Ok(Block {
-			header: BlockHeader {
-				height: height,
-				previous: Hash::from_vec(previous),
-				timestamp: time::at_utc(time::Timespec {
-					sec: timestamp,
-					nsec: 0,
-				}),
-				cuckoo_len: cuckoo_len,
-				target: target,
-				utxo_merkle: Hash::from_vec(utxo_merkle),
-				tx_merkle: Hash::from_vec(tx_merkle),
-				pow: Proof(pow),
-				nonce: nonce,
-			},
+			header: header,
 			inputs: inputs,
 			outputs: outputs,
 			proofs: proofs,

core/src/pow/mod.rs

@@ -88,21 +88,21 @@ impl PowHeader {
 }
 
 /// Validates the proof of work of a given header.
-pub fn verify(b: &Block, target: Target) -> bool {
-	verify_size(b, target, b.header.cuckoo_len as u32)
+pub fn verify(b: &Block) -> bool {
+	verify_size(b, b.header.cuckoo_len as u32)
 }
 
 /// Same as default verify function but uses the much easier Cuckoo20 (mostly
 /// for tests).
-pub fn verify20(b: &Block, target: Target) -> bool {
-	verify_size(b, target, 20)
+pub fn verify20(b: &Block) -> bool {
+	verify_size(b, 20)
 }
 
-pub fn verify_size(b: &Block, target: Target, sizeshift: u32) -> bool {
+pub fn verify_size(b: &Block, sizeshift: u32) -> bool {
 	let hash = PowHeader::from_block(b).hash();
 	// make sure the hash is smaller than our target before going into more
 	// expensive validation
-	if target < b.header.pow.to_target() {
+	if b.header.target < b.header.pow.to_target() {
 		return false;
 	}
 	Cuckoo::new(hash.to_slice(), sizeshift).verify(b.header.pow, EASINESS as u64)
@@ -165,6 +165,6 @@ mod test {
 		assert!(proof.to_target() < MAX_TARGET);
 		b.header.pow = proof;
 		b.header.nonce = nonce;
-		assert!(verify20(&b, MAX_TARGET));
+		assert!(verify20(&b));
 	}
 }