feat: change BLOCKHASH opcode behavior to `keccak(chain_id || block…

…_number)`
scroll-tech · Dec 11, 2023 · 4f9b290 · 4f9b290
1 parent ee9b3d9
commit 4f9b290
Showing 1 changed file with 16 additions and 1 deletion.
diff --git a/core/vm/instructions.go b/core/vm/instructions.go
@@ -447,7 +447,22 @@ func opBlockhash(pc *uint64, interpreter *EVMInterpreter, scope *ScopeContext) (
 		lower = upper - 256
 	}
 	if num64 >= lower && num64 < upper {
-		num.SetBytes(interpreter.evm.Context.GetHash(num64).Bytes())
+		chainId := interpreter.evm.ChainConfig().ChainID
+		chainIdBuf := make([]byte, 8)
+		binary.BigEndian.PutUint64(chainIdBuf, chainId.Uint64())
+		num64Buf := make([]byte, 8)
+		binary.BigEndian.PutUint64(num64Buf, num64)
+
+		if interpreter.hasher == nil {
+			interpreter.hasher = sha3.NewLegacyKeccak256().(keccakState)
+		} else {
+			interpreter.hasher.Reset()
+		}
+		interpreter.hasher.Write(chainIdBuf)
+		interpreter.hasher.Write(num64Buf)
+		interpreter.hasher.Read(interpreter.hasherBuf[:])
+
+		num.SetBytes(interpreter.hasherBuf[:])
 	} else {
 		num.Clear()
 	}