rc4 doesn't use iv

and plain cipher for aead for fun

shadowsocks-csharp/Encryption/AEAD/AEADNativeEncryptor.cs

@@ -0,0 +1,51 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Shadowsocks.Encryption.AEAD
+{
+    public class AEADNativeEncryptor : AEADEncryptor
+    {
+        public AEADNativeEncryptor(string method, string password)
+            : base(method, password)
+        {
+        }
+
+        public override void cipherDecrypt(byte[] ciphertext, uint clen, byte[] plaintext, ref uint plen)
+        {
+            Array.Copy(ciphertext, plaintext, 0);
+            plen = clen;
+
+        }
+
+        public override void cipherEncrypt(byte[] plaintext, uint plen, byte[] ciphertext, ref uint clen)
+        {
+            Array.Copy(plaintext, ciphertext, 0);
+            clen = plen;
+        }
+
+        public override void Dispose()
+        {
+            return;
+        }
+
+        private static Dictionary<string, EncryptorInfo> _ciphers = new Dictionary<string, EncryptorInfo>()
+        {
+            {"plain-aeadfmt",new EncryptorInfo("PLAIN",0,0,0,0,0) }
+        };
+
+
+        protected override Dictionary<string, EncryptorInfo> getCiphers()
+        {
+            return _ciphers;
+        }
+
+        public static IEnumerable<string> SupportedCiphers()
+        {
+            return _ciphers.Keys;
+        }
+
+    }
+}

shadowsocks-csharp/Encryption/EncryptorFactory.cs

@@ -52,6 +52,11 @@ namespace Shadowsocks.Encryption
                     _registeredEncryptors.Add(method, typeof(StreamMbedTLSEncryptor));
             }
 
+            foreach (string method in AEADNativeEncryptor.SupportedCiphers())
+            {
+                if (!_registeredEncryptors.ContainsKey(method))
+                    _registeredEncryptors.Add(method, typeof(AEADNativeEncryptor));
+            }
 
             foreach (string method in AEADOpenSSLEncryptor.SupportedCiphers())
             {

shadowsocks-csharp/Encryption/Stream/StreamNativeEncryptor.cs

@@ -93,7 +93,7 @@ namespace Shadowsocks.Encryption.Stream
         {
             {"plain", new EncryptorInfo("PLAIN", 0, 0, Plain) },
             {"table", new EncryptorInfo("TABLE", 0, 0, Table) },
-            { "rc4", new EncryptorInfo("RC4", 16, 16, Rc4) },
+            { "rc4", new EncryptorInfo("RC4", 16, 0, Rc4) }, // original RC4 doesn't use IV
             { "rc4-md5", new EncryptorInfo("RC4", 16, 16, Rc4Md5) },
         };
 

shadowsocks-csharp/shadowsocks-csharp.csproj

@@ -116,6 +116,7 @@
     <Compile Include="Controller\System\Hotkeys\HotkeyCallbacks.cs" />
     <Compile Include="Encryption\AEAD\AEADEncryptor.cs" />
     <Compile Include="Encryption\AEAD\AEADMbedTLSEncryptor.cs" />
+    <Compile Include="Encryption\AEAD\AEADNativeEncryptor.cs" />
     <Compile Include="Encryption\AEAD\AEADOpenSSLEncryptor.cs" />
     <Compile Include="Encryption\AEAD\AEADSodiumEncryptor.cs" />
     <Compile Include="Encryption\CircularBuffer\ByteCircularBuffer.cs" />