Merge pull request #129 from ethcore/verification

Some missing checks for verification

test-data/src/block.rs

@@ -352,6 +352,7 @@ impl<F> TransactionInputBuilder<F> where F: Invoke<chain::TransactionInput> {
 
 	pub fn coinbase(mut self) -> Self {
 		self.output = Some(chain::OutPoint { hash: H256::from(0), index: 0xffffffff });
+		self.signature = vec![0u8; 2].into();
 		self
 	}
 

verification/src/chain_verifier.rs

@@ -10,6 +10,7 @@ use utils;
 const BLOCK_MAX_FUTURE: i64 = 2 * 60 * 60; // 2 hours
 const COINBASE_MATURITY: u32 = 100; // 2 hours
 const MAX_BLOCK_SIGOPS: usize = 20000;
+const MAX_BLOCK_SIZE: usize = 1000000;
 
 pub struct ChainVerifier {
 	store: Arc<db::Store>,
@@ -176,6 +177,12 @@ impl Verify for ChainVerifier {
 			return Err(Error::Timestamp);
 		}
 
+		// todo: serialized_size function is at least suboptimal
+		let size = ::serialization::Serializable::serialized_size(block);
+		if size > MAX_BLOCK_SIZE {
+			return Err(Error::Size(size))
+		}
+
 		// verify merkle root
 		if block.merkle_root() != block.header().merkle_root_hash {
 			return Err(Error::MerkleRoot);
@@ -186,6 +193,14 @@ impl Verify for ChainVerifier {
 			return Err(Error::Coinbase)
 		}
 
+		// check that coinbase has a valid signature
+		let coinbase = &block.transactions()[0];
+		// is_coinbase() = true above guarantees that there is at least one input
+		let coinbase_script_len = coinbase.inputs[0].script_sig().len();
+		if coinbase_script_len < 2 || coinbase_script_len > 100 {
+			return Err(Error::CoinbaseSignatureLength(coinbase_script_len));
+		}
+
 		// verify transactions (except coinbase)
 		let mut block_sigops = try!(
 			utils::transaction_sigops(&block.transactions()[0])

verification/src/lib.rs

@@ -50,6 +50,10 @@ pub enum Error {
 	/// Maximum sigops operations exceeded - will not provide how much it was in total
 	/// since it stops counting once `MAX_BLOCK_SIGOPS` is reached
 	MaximumSigops,
+	/// Coinbase signature is not in the range 2-100
+	CoinbaseSignatureLength(usize),
+	/// Block size is invalid
+	Size(usize),
 }
 
 #[derive(Debug, PartialEq)]