重构 Encryptor

Editor/Data/RvaDataAllocator.cs

@@ -38,7 +38,7 @@ namespace Obfuz.Data
         {
             public FieldDef holderDataField;
             public FieldDef runtimeValueField;
-            public long encryptionOps;
+            public int encryptionOps;
             public uint size;
             public List<byte> bytes;
             public int salt;
@@ -134,7 +134,7 @@ namespace Obfuz.Data
                 runtimeValueField = runtimeValueField,
                 size = dataHolderType.ClassSize,
                 bytes = new List<byte>((int)dataHolderType.ClassSize),
-                encryptionOps = _random.NextLong(),
+                encryptionOps = _random.NextInt(),
                 salt = _random.NextInt(),
             };
             _rvaFields.Add(newRvaField);
@@ -252,7 +252,7 @@ namespace Obfuz.Data
                 ins.Add(Instruction.Create(OpCodes.Call, importer.InitializedArrayMethod));
 
                 // EncryptionService.DecryptBlock(array, field.encryptionOps, field.salt);
-                ins.Add(Instruction.Create(OpCodes.Ldc_I8, field.encryptionOps));
+                ins.Add(Instruction.CreateLdcI4(field.encryptionOps));
                 ins.Add(Instruction.Create(OpCodes.Ldc_I4, field.salt));
                 ins.Add(Instruction.Create(OpCodes.Call, importer.DecryptBlock));
 

Editor/Emit/DefaultMetadataImporter.cs

@@ -26,9 +26,9 @@ namespace Obfuz.Emit
             Assert.IsNotNull(_initializeArray);
 
             Type encryptionService = typeof(EncryptionService);
-            _encryptBlock = mod.Import(encryptionService.GetMethod("EncryptBlock", new[] { typeof(byte[]), typeof(long), typeof(int) }));
+            _encryptBlock = mod.Import(encryptionService.GetMethod("EncryptBlock", new[] { typeof(byte[]), typeof(int), typeof(int) }));
             Assert.IsNotNull(_encryptBlock);
-            _decryptBlock = mod.Import(encryptionService.GetMethod("DecryptBlock", new[] { typeof(byte[]), typeof(long), typeof(int) }));
+            _decryptBlock = mod.Import(encryptionService.GetMethod("DecryptBlock", new[] { typeof(byte[]), typeof(int), typeof(int) }));
             Assert.IsNotNull(_decryptBlock);
             _encryptInt = mod.Import(encryptionService.GetMethod("Encrypt", new[] { typeof(int), typeof(int), typeof(int) }));
             Assert.IsNotNull(_encryptInt);

Editor/Encryption/EncryptVirtualMachineSimulator.cs

@@ -1,257 +0,0 @@
-using Obfuz.Utils;
-using System;
-using System.Collections.Generic;
-using System.Linq.Expressions;
-using System.Runtime.CompilerServices;
-using System.Text;
-using Unity.Collections.LowLevel.Unsafe;
-using UnityEngine.Assertions;
-using UnityEngine.UIElements;
-
-namespace Obfuz.Encryption
-{
-    public class VirtualMachine
-    {
-        public const int SecretKeyLength = 1024;
-
-        public readonly int vmSeed;
-        public readonly EncryptOpCode[] opCodes;
-
-        public VirtualMachine(int vmSeed, EncryptOpCode[] opCodes)
-        {
-            this.vmSeed = vmSeed;
-            this.opCodes = opCodes;
-        }
-    }
-
-    public interface IVirtualMachineCreator
-    {
-        VirtualMachine CreateVirtualMachine(int opCodeCount, int vmSeed);
-    }
-
-    public class RandomVirtualMachineCreator : IVirtualMachineCreator
-    {
-        private readonly int[] _debugSecretKey;
-
-        public RandomVirtualMachineCreator()
-        {
-            _debugSecretKey = new int[VirtualMachine.SecretKeyLength];
-            for (int i = 0; i < _debugSecretKey.Length; i++)
-            {
-                _debugSecretKey[i] = i;
-            }
-        }
-
-        private IEncryptInstruction CreateRandomInstruction(IRandom random, int secretKeyLength)
-        {
-            switch (random.NextInt(3))
-            {
-                case 0:
-                    return new AddInstruction(random.NextInt(), random.NextInt(secretKeyLength));
-                case 1:
-                    return new XorInstruction(random.NextInt(), random.NextInt(secretKeyLength));
-                case 2:
-                    return new BitRotateInstruction(random.NextInt(32), random.NextInt(secretKeyLength));
-                default:
-                throw new System.Exception("Invalid instruction type");
-            }
-        }
-
-        private EncryptOpCode CreateEncryptOpCode(ushort code, IRandom r, int opCodeCount)
-        {
-            Assert.IsTrue(code < opCodeCount);
-            var insts = new IEncryptInstruction[opCodeCount];
-            for (int i = 0; i < insts.Length; i++)
-            {
-                IEncryptInstruction inst = CreateRandomInstruction(r, VirtualMachine.SecretKeyLength);
-                Assert.AreEqual(1234, inst.Decrypt(inst.Encrypt(1234, _debugSecretKey, i), _debugSecretKey, i));
-                insts[i] = CreateRandomInstruction(r, opCodeCount);
-            }
-            var function = new EncryptFunction(insts);
-            Assert.AreEqual(1234, function.Decrypt(function.Encrypt(1234, _debugSecretKey, code), _debugSecretKey, code));
-            return new EncryptOpCode(code, function);
-        }
-
-        public VirtualMachine CreateVirtualMachine(int opCodeCount, int vmSeed)
-        {
-            Assert.IsTrue(opCodeCount > 0);
-            Assert.AreEqual(0, opCodeCount ^ (opCodeCount - 1));
-            IRandom r = new RandomWithKey(new byte[] {1,2,3,4,5,6}, vmSeed);
-            var opCodes = new EncryptOpCode[opCodeCount];
-            for (int i = 0; i < opCodes.Length; i++)
-            {
-                opCodes[i] = CreateEncryptOpCode((ushort)i, r, opCodeCount);
-            }
-            return new VirtualMachine(vmSeed, opCodes);
-        }
-    }
-
-    public class EncryptVirtualMachineSimulator
-    {
-        private readonly EncryptOpCode[] _opCodes;
-        private readonly int[] _secretKey;
-
-        public EncryptVirtualMachineSimulator(EncryptOpCode[] opCodes, int[] secretKey)
-        {
-            _opCodes = opCodes;
-            // should be power of 2
-            Assert.AreEqual(0, opCodes.Length ^ (opCodes.Length - 1));
-            _secretKey = secretKey;
-        }
-
-        private List<ushort> DecodeOps(int ops)
-        {
-            var codes = new List<ushort>();
-            while (ops > 0)
-            {
-                var code = (ushort)(ops % _opCodes.Length);
-                codes.Add(code);
-                ops >>= 16;
-            }
-            return codes;
-        }
-
-        public int Encrypt(int value, int ops, int salt)
-        {
-            var codes = DecodeOps(ops);
-            foreach (var code in codes)
-            {
-                var opCode = _opCodes[code];
-                value = opCode.Encrypt(value, _secretKey, salt);
-            }
-            return value;
-        }
-
-        public int Decrypt(int value, int ops, int salt)
-        {
-            var codes = DecodeOps(ops);
-            for (int i = codes.Count - 1; i >= 0; i--)
-            {
-                var opCode = _opCodes[codes[i]];
-                value = opCode.Decrypt(value, _secretKey, salt);
-            }
-            return value;
-        }
-
-        public long Encrypt(long value, int ops, int salt)
-        {
-            int low = (int)(value & 0xFFFFFFFF);
-            int high = (int)((value >> 32) & 0xFFFFFFFF);
-            var codes = DecodeOps(ops);
-            
-            // TODO we should encrypt high with encLow
-            int encLow = Encrypt(low, ops, salt);
-            int encHigh = Encrypt(high, ops, salt);
-            
-            return ((long)encHigh << 32) | (long)(uint)(encLow);
-        }
-
-        public long Decrypt(long value, int ops, int salt)
-        {
-            int low = (int)(value & 0xFFFFFFFF);
-            int high = (int)((value >> 32) & 0xFFFFFFFF);
-            var codes = DecodeOps(ops);
-
-            // TODO we should encrypt high with encLow
-            int decLow = Decrypt(low, ops, salt);
-            int decHigh = Decrypt(high, ops, salt);
-
-            return ((long)decHigh << 32) | (long)(uint)(decLow);
-        }
-
-        public float Encrypt(float value, int ops, int salt)
-        {
-            int intValue = UnsafeUtility.As<float, int>(ref value);
-            int encValue = Encrypt(intValue, ops, salt);
-            return UnsafeUtility.As<int, float>(ref encValue);
-        }
-
-        public float Decrypt(float value, int ops, int salt)
-        {
-            int intValue = UnsafeUtility.As<float, int>(ref value);
-            int decValue = Decrypt(intValue, ops, salt);
-            return UnsafeUtility.As<int, float>(ref decValue);
-        }
-
-        public double Encrypt(double value, int ops, int salt)
-        {
-            long longValue = UnsafeUtility.As<double, long>(ref value);
-            long encValue = Encrypt(longValue, ops, salt);
-            return UnsafeUtility.As<long, double>(ref encValue);
-        }
-
-        public double Decrypt(double value, int ops, int salt)
-        {
-            long longValue = UnsafeUtility.As<double, long>(ref value);
-            long decValue = Decrypt(longValue, ops, salt);
-            return UnsafeUtility.As<long, double>(ref decValue);
-        }
-
-        public unsafe byte[] Encrypt(byte[] bytes, int offset, int length, int ops, int salt)
-        {
-            if (length == 0)
-            {
-                return Array.Empty<byte>();
-            }
-            // align size to 4
-            int align4Length = (length + 3) & ~3;
-            byte[] encInts = new byte[align4Length];
-            Buffer.BlockCopy(bytes, offset, encInts, 0, length);
-
-            int intLength = align4Length >> 2;
-            fixed (byte* intArr = &bytes[0])
-            {
-                for (int i = 0; i < intLength; i++)
-                {
-                    int* ele = (int*)intArr + i;
-                    *ele = Encrypt(*ele, ops, salt);
-                }
-            }
-            return encInts;
-        }
-
-        public unsafe byte[] Decrypt(byte[] value, int offset, int length, int ops, int salt)
-        {
-            if (length == 0)
-            {
-                return Array.Empty<byte>();
-            }
-            int align4Length = (length + 3) & ~3;
-            int intLength = align4Length >> 2;
-            byte[] decInts = new byte[align4Length];
-            fixed (byte* intArr = &decInts[0])
-            {
-                for (int i = 0; i < intLength; i++)
-                {
-                    int* ele = (int*)intArr + i;
-                    *ele = Decrypt(*ele, ops, salt);
-                }
-            }
-            return decInts;
-        }
-
-        public byte[] Encrypt(byte[] bytes, int ops, int salt)
-        {
-            return Encrypt(bytes, 0, bytes.Length, ops, salt);
-        }
-
-        public byte[] Encrypt(string value, int ops, int salt)
-        {
-            if (value.Length == 0)
-            {
-                return Array.Empty<byte>();
-            }
-            byte[] bytes = System.Text.Encoding.UTF8.GetBytes(value);
-            return Encrypt(bytes, 0, bytes.Length, ops, salt);
-        }
-
-        public string DecryptString(byte[] value, int offset, int length, int ops, int salt)
-        {
-            if (length == 0)
-            {
-                return string.Empty;
-            }
-            return System.Text.Encoding.UTF8.GetString(Decrypt(value, offset, length, ops, salt));
-        }
-    }
-}

Editor/Encryption/EncryptionVirtualMachineSimulator.cs

@@ -0,0 +1,60 @@
+using System;
+using System.Collections.Generic;
+using System.Linq.Expressions;
+using System.Runtime.CompilerServices;
+using System.Text;
+using Unity.Collections.LowLevel.Unsafe;
+using UnityEngine.Assertions;
+using UnityEngine.UIElements;
+
+namespace Obfuz.Encryption
+{
+
+    public class EncryptionVirtualMachineSimulator : EncryptorBase
+    {
+        private readonly EncryptOpCode[] _opCodes;
+        private readonly int[] _secretKey;
+
+        public EncryptionVirtualMachineSimulator(EncryptOpCode[] opCodes, int[] secretKey)
+        {
+            _opCodes = opCodes;
+            // should be power of 2
+            Assert.AreEqual(0, opCodes.Length ^ (opCodes.Length - 1));
+            _secretKey = secretKey;
+        }
+
+        private List<ushort> DecodeOps(int ops)
+        {
+            var codes = new List<ushort>();
+            while (ops > 0)
+            {
+                var code = (ushort)(ops % _opCodes.Length);
+                codes.Add(code);
+                ops >>= 16;
+            }
+            return codes;
+        }
+
+        public override int Encrypt(int value, int ops, int salt)
+        {
+            var codes = DecodeOps(ops);
+            foreach (var code in codes)
+            {
+                var opCode = _opCodes[code];
+                value = opCode.Encrypt(value, _secretKey, salt);
+            }
+            return value;
+        }
+
+        public override int Decrypt(int value, int ops, int salt)
+        {
+            var codes = DecodeOps(ops);
+            for (int i = codes.Count - 1; i >= 0; i--)
+            {
+                var opCode = _opCodes[codes[i]];
+                value = opCode.Decrypt(value, _secretKey, salt);
+            }
+            return value;
+        }
+    }
+}

Editor/Encryption/IVirtualMachineCreator.cs

@@ -0,0 +1,7 @@
+namespace Obfuz.Encryption
+{
+    public interface IVirtualMachineCreator
+    {
+        VirtualMachine CreateVirtualMachine(int opCodeCount, int vmSeed);
+    }
+}

Editor/Encryption/RandomVirtualMachineCreator.cs

@@ -0,0 +1,62 @@
+using Obfuz.Utils;
+using UnityEngine.Assertions;
+
+namespace Obfuz.Encryption
+{
+    public class RandomVirtualMachineCreator : IVirtualMachineCreator
+    {
+        private readonly int[] _debugSecretKey;
+
+        public RandomVirtualMachineCreator()
+        {
+            _debugSecretKey = new int[VirtualMachine.SecretKeyLength];
+            for (int i = 0; i < _debugSecretKey.Length; i++)
+            {
+                _debugSecretKey[i] = i;
+            }
+        }
+
+        private IEncryptInstruction CreateRandomInstruction(IRandom random, int secretKeyLength)
+        {
+            switch (random.NextInt(3))
+            {
+                case 0:
+                    return new AddInstruction(random.NextInt(), random.NextInt(secretKeyLength));
+                case 1:
+                    return new XorInstruction(random.NextInt(), random.NextInt(secretKeyLength));
+                case 2:
+                    return new BitRotateInstruction(random.NextInt(32), random.NextInt(secretKeyLength));
+                default:
+                throw new System.Exception("Invalid instruction type");
+            }
+        }
+
+        private EncryptOpCode CreateEncryptOpCode(ushort code, IRandom r, int opCodeCount)
+        {
+            Assert.IsTrue(code < opCodeCount);
+            var insts = new IEncryptInstruction[opCodeCount];
+            for (int i = 0; i < insts.Length; i++)
+            {
+                IEncryptInstruction inst = CreateRandomInstruction(r, VirtualMachine.SecretKeyLength);
+                Assert.AreEqual(1234, inst.Decrypt(inst.Encrypt(1234, _debugSecretKey, i), _debugSecretKey, i));
+                insts[i] = CreateRandomInstruction(r, opCodeCount);
+            }
+            var function = new EncryptFunction(insts);
+            Assert.AreEqual(1234, function.Decrypt(function.Encrypt(1234, _debugSecretKey, code), _debugSecretKey, code));
+            return new EncryptOpCode(code, function);
+        }
+
+        public VirtualMachine CreateVirtualMachine(int opCodeCount, int vmSeed)
+        {
+            Assert.IsTrue(opCodeCount > 0);
+            Assert.AreEqual(0, opCodeCount ^ (opCodeCount - 1));
+            IRandom r = new RandomWithKey(new byte[] {1,2,3,4,5,6}, vmSeed);
+            var opCodes = new EncryptOpCode[opCodeCount];
+            for (int i = 0; i < opCodes.Length; i++)
+            {
+                opCodes[i] = CreateEncryptOpCode((ushort)i, r, opCodeCount);
+            }
+            return new VirtualMachine(vmSeed, opCodes);
+        }
+    }
+}

Editor/Encryption/VirtualMachine.cs

@@ -0,0 +1,16 @@
+namespace Obfuz.Encryption
+{
+    public class VirtualMachine
+    {
+        public const int SecretKeyLength = 1024;
+
+        public readonly int vmSeed;
+        public readonly EncryptOpCode[] opCodes;
+
+        public VirtualMachine(int vmSeed, EncryptOpCode[] opCodes)
+        {
+            this.vmSeed = vmSeed;
+            this.opCodes = opCodes;
+        }
+    }
+}

Editor/Obfuscator.cs

@@ -68,7 +68,7 @@ namespace Obfuz
 
 
             var random = new RandomWithKey(_secretKey, _globalRandomSeed);
-            var encryptor = new DefaultEncryptor(_secretKey);
+            var encryptor = new NullEncryptor(_secretKey);
             var rvaDataAllocator = new RvaDataAllocator(random, encryptor);
             var constFieldAllocator = new ConstFieldAllocator(encryptor, random, rvaDataAllocator);
             _ctx = new ObfuscationPassContext

Editor/Settings/EncryptionVMSettings.cs

@@ -0,0 +1,19 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using UnityEngine;
+
+namespace Obfuz.Settings
+{
+    [Serializable]
+    public class EncryptionVMSettings
+    {
+        [Tooltip("secret key for generating encryption virtual machine source code")]
+        public string codeGenerationSecretKey = "Obfuz";
+
+        [Tooltip("encryption virtual machine source code output dir")]
+        public string codeOutputDir = "Assets/Obfuz";
+    }
+}

Editor/Settings/ObfuzSettings.cs

@@ -32,6 +32,9 @@ namespace Obfuz.Settings
         [Tooltip("global random seed")]
         public int globalRandomSeed = 0;
 
+        [Tooltip("encryption virtual machine settings")]
+        public EncryptionVMSettings encryptionVMSettings;
+
         [Tooltip("symbol obfuscation settings")]
         public SymbolObfusSettings symbolObfusSettings;
 

Editor/Settings/ObfuzSettingsProvider.cs

@@ -37,6 +37,8 @@ namespace Obfuz.Settings
         private SerializedProperty _secretKey;
         private SerializedProperty _globalRandomSeed;
         
+        private SerializedProperty _encryptionVMSettings;
+
         private SerializedProperty _symbolObfusSettings;
         private SerializedProperty _constEncryptSettings;
         private SerializedProperty _fieldEncryptSettings;
@@ -71,6 +73,8 @@ namespace Obfuz.Settings
             _secretKey = _serializedObject.FindProperty("secretKey");
             _globalRandomSeed = _serializedObject.FindProperty("globalRandomSeed");
 
+            _encryptionVMSettings = _serializedObject.FindProperty("encryptionVMSettings");
+
             _symbolObfusSettings = _serializedObject.FindProperty("symbolObfusSettings");
             _constEncryptSettings = _serializedObject.FindProperty("constEncryptSettings");
             _fieldEncryptSettings = _serializedObject.FindProperty("fieldEncryptSettings");
@@ -95,6 +99,8 @@ namespace Obfuz.Settings
             EditorGUILayout.PropertyField(_secretKey);
             EditorGUILayout.PropertyField(_globalRandomSeed);
 
+            EditorGUILayout.PropertyField(_encryptionVMSettings);
+
             EditorGUILayout.PropertyField(_symbolObfusSettings);
             EditorGUILayout.PropertyField(_constEncryptSettings);
             EditorGUILayout.PropertyField(_fieldEncryptSettings);

Editor/Settings/SymbolObfusSettings.cs

@@ -15,7 +15,7 @@ namespace Obfuz.Settings
         [Tooltip("prefix for obfuscated name to avoid name confliction with original name")]
         public string obfuscatedNamePrefix = "$";
 
-        [Tooltip("obfuscate same namespace to same name")]
+        [Tooltip("obfuscate same namespace to one name")]
         public bool useConsistentNamespaceObfuscation = true;
 
         [Tooltip("path of mapping.xml")]

Runtime/DefaultEncryptor.cs

@@ -1,102 +0,0 @@
-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Text;
-using System.Threading.Tasks;
-
-namespace Obfuz
-{
-    public class DefaultEncryptor : IEncryptor
-    {
-        private readonly byte[] _key;
-
-        public DefaultEncryptor(byte[] key)
-        {
-            _key = key;
-        }
-
-        public void EncryptBlock(byte[] data, long ops, int salt)
-        {
-            for (int i = 0; i < data.Length; i++)
-            {
-                data[i] ^= (byte)(_key[i % _key.Length] ^ salt);
-            }
-        }
-
-        public void DecryptBlock(byte[] data, long ops, int salt)
-        {
-            for (int i = 0; i < data.Length; i++)
-            {
-                data[i] ^= (byte)(_key[i % _key.Length] ^ salt);
-            }
-        }
-
-        public int Encrypt(int value, int opts, int salt)
-        {
-            return value;
-        }
-
-        public int Decrypt(int value, int opts, int salt)
-        {
-            return value;
-        }
-
-        public long Encrypt(long value, int opts, int salt)
-        {
-            return value;
-        }
-
-        public long Decrypt(long value, int opts, int salt)
-        {
-            return value;
-        }
-
-        public float Encrypt(float value, int opts, int salt)
-        {
-            return value;
-        }
-
-        public float Decrypt(float value, int opts, int salt)
-        {
-            return value;
-        }
-
-        public double Encrypt(double value, int opts, int salt)
-        {
-            return value;
-        }
-
-        public double Decrypt(double value, int opts, int salt)
-        {
-            return value;
-        }
-
-        public byte[] Encrypt(byte[] value, int offset, int length, int opts, int salt)
-        {
-            int align4Length = (length + 3) & ~3;
-            var encryptedBytes = new byte[align4Length];
-            Buffer.BlockCopy(value, offset, encryptedBytes, 0, length);
-            return encryptedBytes;
-        }
-
-        public byte[] Decrypt(byte[] value, int offset, int length, int ops, int salt)
-        {
-            byte[] byteArr = new byte[length];
-            Buffer.BlockCopy(value, 0, byteArr, 0, length);
-            return byteArr;
-        }
-
-        public byte[] Encrypt(string value, int ops, int salt)
-        {
-            byte[] bytes = Encoding.UTF8.GetBytes(value);
-            return Encrypt(bytes, 0, bytes.Length, ops, salt);
-        }
-
-        public string DecryptString(byte[] value, int offset, int length, int ops, int salt)
-        {
-            byte[] bytes = new byte[length];
-            Buffer.BlockCopy(value, 0, bytes, 0, length);
-            return Encoding.UTF8.GetString(bytes);
-        }
-    }
-}

Runtime/EncryptionService.cs

@@ -8,14 +8,14 @@ namespace Obfuz
 {
     public static class EncryptionService
     {
-        private static readonly IEncryptor _encryptor = new DefaultEncryptor(new byte[] { 0x1A, 0x2B, 0x3C, 0x4D });
+        private static readonly IEncryptor _encryptor = new NullEncryptor(new byte[] { 0x1A, 0x2B, 0x3C, 0x4D });
 
-        public static void EncryptBlock(byte[] data, long ops, int salt)
+        public static void EncryptBlock(byte[] data, int ops, int salt)
         {
             _encryptor.EncryptBlock(data, ops, salt);
         }
 
-        public static void DecryptBlock(byte[] data, long ops, int salt)
+        public static void DecryptBlock(byte[] data, int ops, int salt)
         {
             _encryptor.DecryptBlock(data, ops, salt);
         }

Runtime/EncryptorBase.cs

@@ -0,0 +1,215 @@
+using System;
+using System.Text;
+using Unity.Collections.LowLevel.Unsafe;
+
+namespace Obfuz
+{
+    public abstract class EncryptorBase : IEncryptor
+    {
+        public abstract int Encrypt(int value, int opts, int salt);
+        public abstract int Decrypt(int value, int opts, int salt);
+
+        public virtual long Encrypt(long value, int opts, int salt)
+        {
+            int low = (int)value;
+            int high = (int)(value >> 32);
+            int encryptedLow = Encrypt(low, opts, salt);
+            int encryptedHigh = Encrypt(high, opts, salt);
+            return ((long)encryptedHigh << 32) | (uint)encryptedLow;
+        }
+
+        public virtual long Decrypt(long value, int opts, int salt)
+        {
+            int low = (int)value;
+            int high = (int)(value >> 32);
+            int decryptedLow = Decrypt(low, opts, salt);
+            int decryptedHigh = Decrypt(high, opts, salt);
+            return ((long)decryptedHigh << 32) | (uint)decryptedLow;
+        }
+
+        public virtual float Encrypt(float value, int opts, int salt)
+        {
+            ref int intValue = ref UnsafeUtility.As<float, int>(ref value);
+            intValue = Encrypt(intValue, opts, salt);
+            return value;
+        }
+
+        public virtual float Decrypt(float value, int opts, int salt)
+        {
+            ref int intValue = ref UnsafeUtility.As<float, int>(ref value);
+            intValue = Decrypt(intValue, opts, salt);
+            return value;
+        }
+
+        public virtual double Encrypt(double value, int opts, int salt)
+        {
+            ref long longValue = ref UnsafeUtility.As<double, long>(ref value);
+            longValue = Encrypt(longValue, opts, salt);
+            return value;
+        }
+
+        public virtual double Decrypt(double value, int opts, int salt)
+        {
+            ref long longValue = ref UnsafeUtility.As<double, long>(ref value);
+            longValue = Decrypt(longValue, opts, salt);
+            return value;
+        }
+
+        public virtual unsafe byte[] Encrypt(byte[] value, int offset, int length, int ops, int salt)
+        {
+            if (length == 0)
+            {
+                return Array.Empty<byte>();
+            }
+
+            var encryptedBytes = new byte[length];
+            int intArrLength = length >> 2;
+
+            // align to 4
+            if ((offset & 0x3) != 0)
+            {
+                Buffer.BlockCopy(value, offset, encryptedBytes, 0, length);
+
+                // encrypt int
+
+                fixed (byte* dstBytePtr = &encryptedBytes[0])
+                {
+                    int* dstIntPtr = (int*)dstBytePtr;
+
+                    for (int i = 0; i < intArrLength; i++)
+                    {
+                        dstIntPtr[i] = Encrypt(dstIntPtr[i], ops, salt);
+                    }
+                }
+                for (int i = intArrLength * 4; i < length; i++)
+                {
+                    encryptedBytes[i] = (byte)(encryptedBytes[i] ^ salt);
+                }
+            }
+            else
+            {
+                // encrypt int
+                fixed (byte* srcBytePtr = &value[offset])
+                {
+                    fixed (byte* dstBytePtr = &encryptedBytes[0])
+                    {
+                        int* srcIntPtr = (int*)srcBytePtr;
+                        int* dstIntPtr = (int*)dstBytePtr;
+
+                        for (int i = 0; i < intArrLength; i++)
+                        {
+                            dstIntPtr[i] = Encrypt(srcIntPtr[i], ops, salt);
+                        }
+                    }
+                }
+                for (int i = intArrLength * 4; i < length; i++)
+                {
+                    encryptedBytes[i] = (byte)(value[offset + i] ^ salt);
+                }
+            }
+            return encryptedBytes;
+        }
+
+        public unsafe virtual byte[] Decrypt(byte[] value, int offset, int length, int ops, int salt)
+        {
+            var decryptedBytes = new byte[length];
+            int intArrLength = length >> 2;
+
+            // align to 4
+            if ((offset & 0x3) != 0)
+            {
+                Buffer.BlockCopy(value, offset, decryptedBytes, 0, length);
+
+                // encrypt int
+
+                fixed (byte* dstBytePtr = &decryptedBytes[0])
+                {
+                    int* dstIntPtr = (int*)dstBytePtr;
+
+                    for (int i = 0; i < intArrLength; i++)
+                    {
+                        dstIntPtr[i] = Decrypt(dstIntPtr[i], ops, salt);
+                    }
+                }
+                for (int i = intArrLength * 4; i < length; i++)
+                {
+                    decryptedBytes[i] = (byte)(decryptedBytes[i] ^ salt);
+                }
+            }
+            else
+            {
+                // encrypt int
+                fixed (byte* srcBytePtr = &value[offset])
+                {
+                    fixed (byte* dstBytePtr = &decryptedBytes[0])
+                    {
+                        int* srcIntPtr = (int*)srcBytePtr;
+                        int* dstIntPtr = (int*)dstBytePtr;
+
+                        for (int i = 0; i < intArrLength; i++)
+                        {
+                            dstIntPtr[i] = Decrypt(srcIntPtr[i], ops, salt);
+                        }
+                    }
+                }
+                for (int i = intArrLength * 4; i < length; i++)
+                {
+                    decryptedBytes[i] = (byte)(value[offset + i] ^ salt);
+                }
+            }
+            return decryptedBytes;
+        }
+
+        public virtual byte[] Encrypt(string value, int ops, int salt)
+        {
+            byte[] bytes = Encoding.UTF8.GetBytes(value);
+            return Encrypt(bytes, 0, bytes.Length, ops, salt);
+        }
+
+        public virtual string DecryptString(byte[] value, int offset, int length, int ops, int salt)
+        {
+            byte[] bytes = Decrypt(value, offset, length, ops, salt);
+            return Encoding.UTF8.GetString(bytes);
+        }
+
+        public virtual unsafe void EncryptBlock(byte[] data, int ops, int salt)
+        {
+            int length = data.Length;
+            int intArrLength = length >> 2;
+
+            fixed (byte* dstBytePtr = &data[0])
+            {
+                int* dstIntPtr = (int*)dstBytePtr;
+
+                for (int i = 0; i < intArrLength; i++)
+                {
+                    dstIntPtr[i] = Encrypt(dstIntPtr[i], ops, salt);
+                }
+            }
+            for (int i = intArrLength * 4; i < length; i++)
+            {
+                data[i] = (byte)(data[i] ^ salt);
+            }
+        }
+
+        public virtual unsafe void DecryptBlock(byte[] data, int ops, int salt)
+        {
+            int length = data.Length;
+            int intArrLength = length >> 2;
+
+            fixed (byte* dstBytePtr = &data[0])
+            {
+                int* dstIntPtr = (int*)dstBytePtr;
+
+                for (int i = 0; i < intArrLength; i++)
+                {
+                    dstIntPtr[i] = Decrypt(dstIntPtr[i], ops, salt);
+                }
+            }
+            for (int i = intArrLength * 4; i < length; i++)
+            {
+                data[i] = (byte)(data[i] ^ salt);
+            }
+        }
+    }
+}

Runtime/IEncryptor.cs

@@ -1,15 +1,13 @@
-using System;
+using System.Collections.Generic;
-using System.Collections.Generic;
 using System.Linq;
-using System.Text;
 using System.Threading.Tasks;
 
 namespace Obfuz
 {
     public interface IEncryptor
     {
-        void EncryptBlock(byte[] data, long ops, int salt);
+        void EncryptBlock(byte[] data, int ops, int salt);
-        void DecryptBlock(byte[] data, long ops, int salt);
+        void DecryptBlock(byte[] data, int ops, int salt);
 
         int Encrypt(int value, int opts, int salt);
         int Decrypt(int value, int opts, int salt);

Runtime/NullEncryptor.cs

@@ -0,0 +1,90 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Obfuz
+{
+    public class NullEncryptor : EncryptorBase
+    {
+        private readonly byte[] _key;
+
+        public NullEncryptor(byte[] key)
+        {
+            _key = key;
+        }
+
+        public override int Encrypt(int value, int opts, int salt)
+        {
+            return value;
+        }
+
+        public override int Decrypt(int value, int opts, int salt)
+        {
+            return value;
+        }
+
+        public override long Encrypt(long value, int opts, int salt)
+        {
+            return value;
+        }
+
+        public override long Decrypt(long value, int opts, int salt)
+        {
+            return value;
+        }
+
+        public override float Encrypt(float value, int opts, int salt)
+        {
+            return value;
+        }
+
+        public override float Decrypt(float value, int opts, int salt)
+        {
+            return value;
+        }
+
+        public override double Encrypt(double value, int opts, int salt)
+        {
+            return value;
+        }
+
+        public override double Decrypt(double value, int opts, int salt)
+        {
+            return value;
+        }
+
+        public override byte[] Encrypt(byte[] value, int offset, int length, int opts, int salt)
+        {
+            if (length == 0)
+            {
+                return Array.Empty<byte>();
+            }
+            var encryptedBytes = new byte[length];
+            Buffer.BlockCopy(value, offset, encryptedBytes, 0, length);
+            return encryptedBytes;
+        }
+
+        public override byte[] Decrypt(byte[] value, int offset, int length, int ops, int salt)
+        {
+            if (length == 0)
+            {
+                return Array.Empty<byte>();
+            }
+            byte[] byteArr = new byte[length];
+            Buffer.BlockCopy(value, 0, byteArr, 0, length);
+            return byteArr;
+        }
+
+        public override byte[] Encrypt(string value, int ops, int salt)
+        {
+            return Encoding.UTF8.GetBytes(value);
+        }
+
+        public override string DecryptString(byte[] value, int offset, int length, int ops, int salt)
+        {
+            return Encoding.UTF8.GetString(value, offset, length);
+        }
+    }
+}