Native encryption

shadowsocks-csharp/Encryption/AEAD/AEADAesGcmNativeEncryptor.cs

@@ -0,0 +1,91 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Security.Cryptography;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Shadowsocks.Encryption.AEAD
+{
+    public class AEADAesGcmNativeEncryptor : AEADNativeEncryptor
+    {
+
+        public AEADAesGcmNativeEncryptor(string method, string password) : base(method, password)
+        {
+        }
+        static int CIPHER_AES = 1;  // dummy
+
+        private static readonly Dictionary<string, EncryptorInfo> _ciphers = new Dictionary<string, EncryptorInfo>
+        {
+            {"aes-128-gcm", new EncryptorInfo("AES-128-GCM", 16, 16, 12, 16, CIPHER_AES)},
+            {"aes-192-gcm", new EncryptorInfo("AES-192-GCM", 24, 24, 12, 16, CIPHER_AES)},
+            {"aes-256-gcm", new EncryptorInfo("AES-256-GCM", 32, 32, 12, 16, CIPHER_AES)},
+        };
+
+        protected override Dictionary<string, EncryptorInfo> getCiphers()
+        {
+            return _ciphers;
+        }
+
+        public override void InitCipher(byte[] salt, bool isEncrypt, bool isUdp)
+        {
+            base.InitCipher(salt, isEncrypt, isUdp);
+
+            DeriveSessionKey(isEncrypt ? encryptSalt : decryptSalt,
+                 _Masterkey, sessionKey);
+        }
+
+        public override void cipherDecrypt(byte[] ciphertext, uint clen, byte[] plaintext, ref uint plen)
+        {
+            using (var aes = new AesGcm(sessionKey))
+            {
+                byte[] tag = new byte[tagLen];
+                byte[] cipherWithoutTag = new byte[clen];
+                Array.Copy(ciphertext, 0, cipherWithoutTag, 0, clen - tagLen);
+                Array.Copy(ciphertext, clen - tagLen, tag, 0, tagLen);
+                aes.Decrypt(decNonce, ciphertext, cipherWithoutTag, tag);
+            }
+            /*var cipher = new GcmBlockCipher(new AesEngine());
+            AeadParameters parameters = new AeadParameters(new KeyParameter(_sessionKey), tagLen * 8, _decNonce);
+
+            cipher.Init(false, parameters);
+            var plaintextBC = new byte[cipher.GetOutputSize((int)clen)];
+            var len = cipher.ProcessBytes(ciphertext, 0, (int)clen, plaintextBC, 0);
+            cipher.DoFinal(plaintextBC, len);
+            plen = (uint)(plaintextBC.Length);
+            Array.Copy(plaintextBC, 0, plaintext, 0, plen);*/
+        }
+
+        public override void cipherEncrypt(byte[] plaintext, uint plen, byte[] ciphertext, ref uint clen)
+        {
+            using (var aes = new AesGcm(sessionKey))
+            {
+                byte[] tag = new byte[tagLen];
+                byte[] cipherWithoutTag = new byte[clen];
+                aes.Encrypt(encNonce, plaintext, cipherWithoutTag, tag);
+                cipherWithoutTag.CopyTo(ciphertext, 0);
+                tag.CopyTo(ciphertext, clen);
+            }
+
+            /*
+            var cipher = new GcmBlockCipher(new AesEngine());
+            AeadParameters parameters = new AeadParameters(new KeyParameter(_sessionKey), tagLen * 8, _encNonce);
+
+            cipher.Init(true, parameters);
+            var ciphertextBC = new byte[cipher.GetOutputSize((int)plen)];
+            var len = cipher.ProcessBytes(plaintext, 0, (int)plen, ciphertextBC, 0);
+            cipher.DoFinal(ciphertextBC, len);
+            clen = (uint)(ciphertextBC.Length);
+            Array.Copy(ciphertextBC, 0, ciphertext, 0, clen);*/
+        }
+
+        public static List<string> SupportedCiphers()
+        {
+            return new List<string>(_ciphers.Keys);
+        }
+
+        public override void Dispose()
+        {
+        }
+    }
+}

shadowsocks-csharp/Encryption/AEAD/AEADBouncyCastleEncryptor.cs

@@ -9,7 +9,7 @@ using System.Threading.Tasks;
 
 namespace Shadowsocks.Encryption.AEAD
 {
-    public class AEADBouncyCastleEncryptor : AEADEncryptor, IDisposable
+    public class AEADBouncyCastleEncryptor : AEADEncryptor
     {
         static int CIPHER_AES = 1;  // dummy
 
@@ -35,14 +35,14 @@ namespace Shadowsocks.Encryption.AEAD
         {
             base.InitCipher(salt, isEncrypt, isUdp);
 
-            DeriveSessionKey(isEncrypt ? _encryptSalt : _decryptSalt,
-                 _Masterkey, _sessionKey);
+            DeriveSessionKey(isEncrypt ? encryptSalt : decryptSalt,
+                 _Masterkey, sessionKey);
         }
 
         public override void cipherDecrypt(byte[] ciphertext, uint clen, byte[] plaintext, ref uint plen)
         {
             var cipher = new GcmBlockCipher(new AesEngine());
-            AeadParameters parameters = new AeadParameters(new KeyParameter(_sessionKey), tagLen * 8, _decNonce);
+            AeadParameters parameters = new AeadParameters(new KeyParameter(sessionKey), tagLen * 8, decNonce);
 
             cipher.Init(false, parameters);
             var plaintextBC = new byte[cipher.GetOutputSize((int)clen)];
@@ -55,7 +55,7 @@ namespace Shadowsocks.Encryption.AEAD
         public override void cipherEncrypt(byte[] plaintext, uint plen, byte[] ciphertext, ref uint clen)
         {
             var cipher = new GcmBlockCipher(new AesEngine());
-            AeadParameters parameters = new AeadParameters(new KeyParameter(_sessionKey), tagLen * 8, _encNonce);
+            AeadParameters parameters = new AeadParameters(new KeyParameter(sessionKey), tagLen * 8, encNonce);
 
             cipher.Init(true, parameters);
             var ciphertextBC = new byte[cipher.GetOutputSize((int)plen)];

shadowsocks-csharp/Encryption/AEAD/AEADEncryptor.cs

@@ -37,18 +37,19 @@ namespace Shadowsocks.Encryption.AEAD
         protected string _innerLibName;
         protected EncryptorInfo CipherInfo;
         protected static byte[] _Masterkey = null;
-        protected byte[] _sessionKey;
+        protected byte[] sessionKey;
         protected int keyLen;
         protected int saltLen;
         protected int tagLen;
         protected int nonceLen;
 
-        protected byte[] _encryptSalt;
-        protected byte[] _decryptSalt;
+        protected byte[] encryptSalt;
+        protected byte[] decryptSalt;
 
         protected object _nonceIncrementLock = new object();
-        protected byte[] _encNonce;
-        protected byte[] _decNonce;
+        protected byte[] encNonce;
+        protected byte[] decNonce;
+
         // Is first packet
         protected bool _decryptSaltReceived;
         protected bool _encryptSaltSent;
@@ -62,8 +63,8 @@ namespace Shadowsocks.Encryption.AEAD
             InitEncryptorInfo(method);
             InitKey(password);
             // Initialize all-zero nonce for each connection
-            _encNonce = new byte[nonceLen];
-            _decNonce = new byte[nonceLen];
+            encNonce = new byte[nonceLen];
+            decNonce = new byte[nonceLen];
         }
 
         protected abstract Dictionary<string, EncryptorInfo> getCiphers();
@@ -93,7 +94,7 @@ namespace Shadowsocks.Encryption.AEAD
             if (_Masterkey.Length != keyLen) Array.Resize(ref _Masterkey, keyLen);
             DeriveKey(passbuf, _Masterkey, keyLen);
             // init session key
-            if (_sessionKey == null) _sessionKey = new byte[keyLen];
+            if (sessionKey == null) sessionKey = new byte[keyLen];
         }
 
         public void DeriveKey(byte[] password, byte[] key, int keylen)
@@ -109,24 +110,22 @@ namespace Shadowsocks.Encryption.AEAD
         protected void IncrementNonce(bool isEncrypt)
         {
             lock (_nonceIncrementLock) {
-                CryptoUtils.SodiumIncrement(isEncrypt ? _encNonce : _decNonce);
+                CryptoUtils.SodiumIncrement(isEncrypt ? encNonce : decNonce);
             }
         }
 
         public virtual void InitCipher(byte[] salt, bool isEncrypt, bool isUdp)
         {
             if (isEncrypt) {
-                _encryptSalt = new byte[saltLen];
-                Array.Copy(salt, _encryptSalt, saltLen);
+                encryptSalt = new byte[saltLen];
+                Array.Copy(salt, encryptSalt, saltLen);
             } else {
-                _decryptSalt = new byte[saltLen];
-                Array.Copy(salt, _decryptSalt, saltLen);
+                decryptSalt = new byte[saltLen];
+                Array.Copy(salt, decryptSalt, saltLen);
             }
             logger.Dump("Salt", salt, saltLen);
         }
 
-        public static void randBytes(byte[] buf, int length) { RNG.GetBytes(buf, length); }
-
         public abstract void cipherEncrypt(byte[] plaintext, uint plen, byte[] ciphertext, ref uint clen);
 
         public abstract void cipherDecrypt(byte[] ciphertext, uint clen, byte[] plaintext, ref uint plen);
@@ -144,7 +143,7 @@ namespace Shadowsocks.Encryption.AEAD
                 _encryptSaltSent = true;
                 // Generate salt
                 byte[] saltBytes = new byte[saltLen];
-                randBytes(saltBytes, saltLen);
+                RNG.GetBytes(saltBytes, saltLen);
                 InitCipher(saltBytes, true, false);
                 Array.Copy(saltBytes, 0, outbuf, 0, saltLen);
                 outlength = saltLen;
@@ -289,7 +288,7 @@ namespace Shadowsocks.Encryption.AEAD
         public override void EncryptUDP(byte[] buf, int length, byte[] outbuf, out int outlength)
         {
             // Generate salt
-            randBytes(outbuf, saltLen);
+            RNG.GetBytes(outbuf, saltLen);
             InitCipher(outbuf, true, true);
             uint olen = 0;
             lock (_udpTmpBuf) {

shadowsocks-csharp/Encryption/EncryptorFactory.cs

@@ -15,10 +15,10 @@ namespace Shadowsocks.Encryption
 
         static EncryptorFactory()
         {
-            foreach (string method in StreamNativeEncryptor.SupportedCiphers())
+            foreach (string method in StreamTableNativeEncryptor.SupportedCiphers())
             {
                 if (!_registeredEncryptors.ContainsKey(method))
-                    _registeredEncryptors.Add(method, typeof(StreamNativeEncryptor));
+                    _registeredEncryptors.Add(method, typeof(StreamTableNativeEncryptor));
             }
 
             foreach (string method in AEADNativeEncryptor.SupportedCiphers())

shadowsocks-csharp/Encryption/Stream/StreamRc4NativeEncryptor.cs

@@ -0,0 +1,127 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Shadowsocks.Encryption.Stream
+{
+    public class StreamRc4NativeEncryptor : StreamEncryptor
+    {
+        const int Rc4 = 0;
+        const int Rc4Md5 = 1;
+
+        string _password;
+
+        byte[] realkey;
+        byte[] sbox;
+        public StreamRc4NativeEncryptor(string method, string password) : base(method, password)
+        {
+            _password = password;
+        }
+
+        public override void Dispose()
+        {
+            return;
+        }
+
+        protected override void initCipher(byte[] iv, bool isEncrypt)
+        {
+            base.initCipher(iv, isEncrypt);
+            if (_cipher == Rc4Md5)
+            {
+                byte[] temp = new byte[keyLen + ivLen];
+                Array.Copy(_key, 0, temp, 0, keyLen);
+                Array.Copy(iv, 0, temp, keyLen, ivLen);
+                realkey = CryptoUtils.MD5(temp);
+            }
+            else
+            {
+                realkey = _key;
+            }
+            sbox = SBox(realkey);
+
+        }
+
+        protected override void cipherUpdate(bool isEncrypt, int length, byte[] buf, byte[] outbuf)
+        {
+            var ctx = isEncrypt ? enc_ctx : dec_ctx;
+
+            byte[] t = new byte[length];
+            Array.Copy(buf, t, length);
+
+            RC4(ctx, sbox, t, length);
+            Array.Copy(t, outbuf, length);
+        }
+
+        private static readonly Dictionary<string, EncryptorInfo> _ciphers = new Dictionary<string, EncryptorInfo>
+        {
+            // original RC4 doesn't use IV
+            { "rc4", new EncryptorInfo("RC4", 16, 0, Rc4) },
+            { "rc4-md5", new EncryptorInfo("RC4", 16, 16, Rc4Md5) },
+        };
+
+        public static IEnumerable<string> SupportedCiphers()
+        {
+            return _ciphers.Keys;
+        }
+
+        protected override Dictionary<string, EncryptorInfo> getCiphers()
+        {
+            return _ciphers;
+        }
+
+        #region RC4
+        class Context
+        {
+            public int index1 = 0;
+            public int index2 = 0;
+        }
+
+        private Context enc_ctx = new Context();
+        private Context dec_ctx = new Context();
+
+        private byte[] SBox(byte[] key)
+        {
+            byte[] s = new byte[256];
+
+            for (int i = 0; i < 256; i++)
+            {
+                s[i] = (byte)i;
+            }
+
+            for (int i = 0, j = 0; i < 256; i++)
+            {
+                j = (j + key[i % key.Length] + s[i]) & 255;
+
+                Swap(s, i, j);
+            }
+
+            return s;
+        }
+
+        private void RC4(Context ctx, byte[] s, byte[] data, int length)
+        {
+            for (int n = 0; n < length; n++)
+            {
+                byte b = data[n];
+
+                ctx.index1 = (ctx.index1 + 1) & 255;
+                ctx.index2 = (ctx.index2 + s[ctx.index1]) & 255;
+
+                Swap(s, ctx.index1, ctx.index2);
+
+                data[n] = (byte)(b ^ s[(s[ctx.index1] + s[ctx.index2]) & 255]);
+            }
+        }
+
+        private static void Swap(byte[] s, int i, int j)
+        {
+            byte c = s[i];
+
+            s[i] = s[j];
+            s[j] = c;
+        }
+        #endregion
+    }
+}

shadowsocks-csharp/Encryption/Stream/StreamNativeEncryptor.cs → shadowsocks-csharp/Encryption/Stream/StreamTableNativeEncryptor.cs

@@ -6,18 +6,14 @@ using System.Threading.Tasks;
 
 namespace Shadowsocks.Encryption.Stream
 {
-    public class StreamNativeEncryptor : StreamEncryptor
+    public class StreamTableNativeEncryptor : StreamEncryptor
     {
         const int Plain = 0;
         const int Table = 1;
-        const int Rc4 = 2;
-        const int Rc4Md5 = 3;
 
         string _password;
 
-        byte[] realkey;
-        byte[] sbox;
-        public StreamNativeEncryptor(string method, string password) : base(method, password)
+        public StreamTableNativeEncryptor(string method, string password) : base(method, password)
         {
             _password = password;
         }
@@ -30,22 +26,7 @@ namespace Shadowsocks.Encryption.Stream
         protected override void initCipher(byte[] iv, bool isEncrypt)
         {
             base.initCipher(iv, isEncrypt);
-            if (_cipher >= Rc4)
-            {
-                if (_cipher == Rc4Md5)
-                {
-                    byte[] temp = new byte[keyLen + ivLen];
-                    Array.Copy(_key, 0, temp, 0, keyLen);
-                    Array.Copy(iv, 0, temp, keyLen, ivLen);
-                    realkey = CryptoUtils.MD5(temp);
-                }
-                else
-                {
-                    realkey = _key;
-                }
-                sbox = SBox(realkey);
-            }
-            else if (_cipher == Table)
+            if (_cipher == Table)
             {
                 ulong a = BitConverter.ToUInt64(CryptoUtils.MD5(Encoding.UTF8.GetBytes(_password)), 0);
                 for (int i = 0; i < 256; i++)
@@ -77,24 +58,12 @@ namespace Shadowsocks.Encryption.Stream
             {
                 Array.Copy(buf, outbuf, length);
             }
-            else
-            {
-                var ctx = isEncrypt ? enc_ctx : dec_ctx;
-
-                byte[] t = new byte[length];
-                Array.Copy(buf, t, length);
-
-                RC4(ctx, sbox, t, length);
-                Array.Copy(t, outbuf, length);
-            }
         }
 
         private static readonly Dictionary<string, EncryptorInfo> _ciphers = new Dictionary<string, EncryptorInfo>
         {
             {"plain", new EncryptorInfo("PLAIN", 0, 0, Plain) },
             {"table", new EncryptorInfo("TABLE", 0, 0, Table) },
-            { "rc4", new EncryptorInfo("RC4", 16, 0, Rc4) }, // original RC4 doesn't use IV
-            { "rc4-md5", new EncryptorInfo("RC4", 16, 16, Rc4Md5) },
         };
 
         public static IEnumerable<string> SupportedCiphers()
@@ -156,58 +125,5 @@ namespace Shadowsocks.Encryption.Stream
             return sorted;
         }
         #endregion
-
-        #region RC4
-        class Context
-        {
-            public int index1 = 0;
-            public int index2 = 0;
-        }
-
-        private Context enc_ctx = new Context();
-        private Context dec_ctx = new Context();
-
-        private byte[] SBox(byte[] key)
-        {
-            byte[] s = new byte[256];
-
-            for (int i = 0; i < 256; i++)
-            {
-                s[i] = (byte)i;
-            }
-
-            for (int i = 0, j = 0; i < 256; i++)
-            {
-                j = (j + key[i % key.Length] + s[i]) & 255;
-
-                Swap(s, i, j);
-            }
-
-            return s;
-        }
-
-        private void RC4(Context ctx, byte[] s, byte[] data, int length)
-        {
-            for (int n = 0; n < length; n++)
-            {
-                byte b = data[n];
-
-                ctx.index1 = (ctx.index1 + 1) & 255;
-                ctx.index2 = (ctx.index2 + s[ctx.index1]) & 255;
-
-                Swap(s, ctx.index1, ctx.index2);
-
-                data[n] = (byte)(b ^ s[(s[ctx.index1] + s[ctx.index2]) & 255]);
-            }
-        }
-
-        private static void Swap(byte[] s, int i, int j)
-        {
-            byte c = s[i];
-
-            s[i] = s[j];
-            s[j] = c;
-        }
-        #endregion
     }
 }

shadowsocks-csharp/shadowsocks-csharp.csproj

@@ -2,7 +2,7 @@
 
   <PropertyGroup>
     <OutputType>WinExe</OutputType>
-    <TargetFrameworks>net472;netcoreapp3.1</TargetFrameworks>
+    <TargetFrameworks>netcoreapp3.1</TargetFrameworks>
     <RootNamespace>Shadowsocks</RootNamespace>
     <UseWindowsForms>true</UseWindowsForms>
     <Authors>clowwindy &amp; community 2020</Authors>

test/CryptographyTest.cs

@@ -111,8 +111,8 @@ namespace Shadowsocks.Test
                 {
                     IEncryptor encryptorN;
                     IEncryptor decryptorN;
-                    encryptorN = new StreamNativeEncryptor("rc4-md5", "barfoo!");
-                    decryptorN = new StreamNativeEncryptor("rc4-md5", "barfoo!");
+                    encryptorN = new StreamRc4NativeEncryptor("rc4-md5", "barfoo!");
+                    decryptorN = new StreamRc4NativeEncryptor("rc4-md5", "barfoo!");
                     RunEncryptionRound(encryptorN, decryptorN);
                 }
             }
@@ -134,7 +134,7 @@ namespace Shadowsocks.Test
                     IEncryptor decryptor;
                     encryptor = new Encryption.AEAD.AEADBouncyCastleEncryptor("aes-256-gcm", "barfoo!");
                     encryptor.AddrBufLength = 1 + 4 + 2;// ADDR_ATYP_LEN + 4 + ADDR_PORT_LEN;
-                    decryptor = new Encryption.AEAD.AEADBouncyCastleEncryptor("aes-256-gcm", "barfoo!");
+                    decryptor = new Encryption.AEAD.AEADAesGcmNativeEncryptor("aes-256-gcm", "barfoo!");
                     decryptor.AddrBufLength = 1 + 4 + 2;// ADDR_ATYP_LEN + 4 + ADDR_PORT_LEN;
                     RunEncryptionRound(encryptor, decryptor);
                 }

test/ShadowsocksTest.csproj

@@ -6,6 +6,10 @@
     <IsPackable>false</IsPackable>
   </PropertyGroup>
 
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|AnyCPU'">
+    <WarningLevel>0</WarningLevel>
+  </PropertyGroup>
+
   <ItemGroup>
     <PackageReference Include="GlobalHotKeyCore" Version="1.2.0" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.5.0" />