Adding keccak256

src/Neo/SmartContract/Native/CryptoLib.cs

@@ -1,17 +1,19 @@
-// Copyright (C) 2015-2022 The Neo Project.
-// 
-// The neo is free software distributed under the MIT software license, 
+// Copyright (C) 2015-2023 The Neo Project.
+//
+// The neo is free software distributed under the MIT software license,
 // see the accompanying file LICENSE in the main directory of the
-// project or http://www.opensource.org/licenses/mit-license.php 
+// project or http://www.opensource.org/licenses/mit-license.php
 // for more details.
-// 
+//
 // Redistribution and use in source and binary forms with or without
 // modifications are permitted.
 
 using Neo.Cryptography;
 using Neo.Cryptography.ECC;
 using System;
 using System.Collections.Generic;
+using System.Text;
+using Org.BouncyCastle.Crypto.Digests;
 
 namespace Neo.SmartContract.Native
 {
@@ -63,6 +65,21 @@ public static byte[] Murmur32(byte[] data, uint seed)
             return murmur.ComputeHash(data);
         }
 
+        /// <summary>
+        /// Computes the hash value for the specified byte array using the keccak256 algorithm.
+        /// </summary>
+        /// <param name="data">The input to compute the hash code for.</param>
+        /// <returns>Computed hash</returns>
+        [ContractMethod(CpuFee = 1 << 15)]
+        public static byte[] Keccak256(byte[] data)
+        {
+            KeccakDigest keccak = new KeccakDigest(256);
+            keccak.BlockUpdate(data, 0, data.Length);
+            byte[] result = new byte[keccak.GetDigestSize()];
+            keccak.DoFinal(result, 0);
+            return result;
+        }
+
         /// <summary>
         /// Verifies that a digital signature is appropriate for the provided key and message using the ECDSA algorithm.
         /// </summary>

tests/Neo.UnitTests/SmartContract/Native/UT_CryptoLib.cs

@@ -4,7 +4,7 @@
 using Neo.SmartContract;
 using Neo.SmartContract.Native;
 using Neo.VM;
-using System.Security.Cryptography;
+using Org.BouncyCastle.Utilities.Encoders;
 
 namespace Neo.UnitTests.SmartContract.Native
 {
@@ -324,5 +324,20 @@ public void TestBls12381ScalarMul_Compat()
                 BLS12381PointType.G2Proj
             );
         }
+
+        [TestMethod]
+        public void TestKeccak256()
+        {
+            // Arrange
+            byte[] inputData = "Hello, Keccak!"u8.ToArray();
+            string expectedHashHex = "49222c3dd1a2b5cf30a8720050c31844dbc8eca466595b5ce9c11932b7aac985";
+
+            // Act
+            byte[] outputData = CryptoLib.Keccak256(inputData);
+            string outputHashHex = Hex.ToHexString(outputData);
+
+            // Assert
+            Assert.AreEqual(expectedHashHex, outputHashHex, "Keccak256 hash did not match expected value.");
+        }
     }
 }