Merge pull request #6 from madeye/feature_rc4

Add RC4 encryption support

shadowsocks-csharp/Config.cs

@@ -14,6 +14,7 @@ namespace shadowsocks_csharp
         public int server_port;
         public int local_port;
         public string password;
+        public string method;
 
         public bool isDefault;
 
@@ -49,6 +50,7 @@ namespace shadowsocks_csharp
                     server_port = 8388,
                     local_port = 1081,
                     password = "barfoo!",
+                    method = "table",
                     isDefault = true
                 };
             }
@@ -65,7 +67,8 @@ namespace shadowsocks_csharp
                         server = config.server,
                         server_port = config.server_port,
                         local_port = config.local_port,
-                        password = config.password
+                        password = config.password,
+                        method = config.method
                     });
                     sw.Write(jsonString);
                     sw.Flush();

shadowsocks-csharp/Encryptor.cs

@@ -7,8 +7,13 @@ namespace shadowsocks_csharp
 {
     class Encryptor
     {
+        public const int TYPE_TABLE = 1;
+        public const int TYPE_RC4 = 2;
+
         public byte[] encryptTable = new byte[256];
         public byte[] decryptTable = new byte[256];
+        public int method = TYPE_TABLE;
+        public RC4 rc4 = null;
 
         private long compare(byte x, byte y, ulong a, int i)
         {
@@ -53,43 +58,65 @@ namespace shadowsocks_csharp
             return sorted;
         }
 
-        public Encryptor(string password)
+        public Encryptor(string method, string password)
         {
             MD5 md5 = System.Security.Cryptography.MD5.Create();
             byte[] inputBytes = System.Text.Encoding.UTF8.GetBytes(password);
             byte[] hash = md5.ComputeHash(inputBytes);
 
-            // TODO endian
-            var a = BitConverter.ToUInt64(hash, 0);
-            for (int i = 0; i < 256; i++)
-            {
-                encryptTable[i] = (byte)i;
-            }
-            for (int i = 1; i < 1024; i++)
-            {
-                encryptTable = mergeSort(encryptTable, a, i);
-            }
-            for (int i = 0; i < 256; i++)
-            {
-                decryptTable[encryptTable[i]] = (byte)i;
+            if (method != null && method.ToLowerInvariant().Equals("rc4")) {
+                Console.WriteLine("init rc4");
+                this.method = TYPE_RC4;
+
+                rc4 = new RC4();
+                encryptTable = rc4.EncryptInitalize(hash);
+                decryptTable = rc4.EncryptInitalize(hash);
+            } else {
+                Console.WriteLine("init table");
+                this.method = TYPE_TABLE;
+
+                // TODO endian
+                var a = BitConverter.ToUInt64(hash, 0);
+                for (int i = 0; i < 256; i++)
+                {
+                    encryptTable[i] = (byte)i;
+                }
+                for (int i = 1; i < 1024; i++)
+                {
+                    encryptTable = mergeSort(encryptTable, a, i);
+                }
+                for (int i = 0; i < 256; i++)
+                {
+                    decryptTable[encryptTable[i]] = (byte)i;
+                }
             }
         }
 
         public void Encrypt(byte[] buf, int length)
         {
-            for (int i = 0; i < length; i++)
+            switch (method)
             {
-                buf[i] = encryptTable[buf[i]];
+                case TYPE_TABLE:
+                    for (int i = 0; i < length; i++)
+                        buf[i] = encryptTable[buf[i]];
+                    break;
+                case TYPE_RC4:
+                    rc4.Encrypt(encryptTable, buf, length);
+                    break;
             }
         }
         public void Decrypt(byte[] buf, int length)
         {
-            for (int i = 0; i < length; i++)
+            switch (method)
             {
-                buf[i] = decryptTable[buf[i]];
+                case TYPE_TABLE:
+                    for (int i = 0; i < length; i++)
+                        buf[i] = decryptTable[buf[i]];
+                    break;
+                case TYPE_RC4:
+                    rc4.Decrypt(decryptTable, buf, length);
+                    break;
             }
         }
-
-
     }
 }

shadowsocks-csharp/Form1.Designer.cs

@@ -31,26 +31,29 @@
             this.components = new System.ComponentModel.Container();
             System.ComponentModel.ComponentResourceManager resources = new System.ComponentModel.ComponentResourceManager(typeof(Form1));
             this.tableLayoutPanel1 = new System.Windows.Forms.TableLayoutPanel();
+            this.label5 = new System.Windows.Forms.Label();
             this.label1 = new System.Windows.Forms.Label();
             this.label2 = new System.Windows.Forms.Label();
+            this.comboBox1 = new System.Windows.Forms.ComboBox();
             this.label3 = new System.Windows.Forms.Label();
             this.label4 = new System.Windows.Forms.Label();
             this.textBox1 = new System.Windows.Forms.TextBox();
             this.textBox2 = new System.Windows.Forms.TextBox();
             this.textBox3 = new System.Windows.Forms.TextBox();
             this.textBox4 = new System.Windows.Forms.TextBox();
-            this.panel1 = new System.Windows.Forms.Panel();
-            this.button2 = new System.Windows.Forms.Button();
-            this.button1 = new System.Windows.Forms.Button();
             this.notifyIcon1 = new System.Windows.Forms.NotifyIcon(this.components);
             this.contextMenuStrip1 = new System.Windows.Forms.ContextMenuStrip(this.components);
             this.ConfigItem = new System.Windows.Forms.ToolStripMenuItem();
             this.aboutToolStripMenuItem = new System.Windows.Forms.ToolStripMenuItem();
             this.toolStripSeparator2 = new System.Windows.Forms.ToolStripSeparator();
             this.QuitItem = new System.Windows.Forms.ToolStripMenuItem();
+            this.panel2 = new System.Windows.Forms.Panel();
+            this.button1 = new System.Windows.Forms.Button();
+            this.button2 = new System.Windows.Forms.Button();
+            this.panel1 = new System.Windows.Forms.Panel();
             this.tableLayoutPanel1.SuspendLayout();
-            this.panel1.SuspendLayout();
             this.contextMenuStrip1.SuspendLayout();
+            this.panel1.SuspendLayout();
             this.SuspendLayout();
             // 
             // tableLayoutPanel1
@@ -60,33 +63,44 @@
             this.tableLayoutPanel1.ColumnCount = 2;
             this.tableLayoutPanel1.ColumnStyles.Add(new System.Windows.Forms.ColumnStyle());
             this.tableLayoutPanel1.ColumnStyles.Add(new System.Windows.Forms.ColumnStyle());
+            this.tableLayoutPanel1.Controls.Add(this.label5, 0, 4);
             this.tableLayoutPanel1.Controls.Add(this.label1, 0, 0);
             this.tableLayoutPanel1.Controls.Add(this.label2, 0, 1);
+            this.tableLayoutPanel1.Controls.Add(this.comboBox1, 1, 4);
             this.tableLayoutPanel1.Controls.Add(this.label3, 0, 2);
             this.tableLayoutPanel1.Controls.Add(this.label4, 0, 3);
             this.tableLayoutPanel1.Controls.Add(this.textBox1, 1, 0);
             this.tableLayoutPanel1.Controls.Add(this.textBox2, 1, 1);
             this.tableLayoutPanel1.Controls.Add(this.textBox3, 1, 2);
             this.tableLayoutPanel1.Controls.Add(this.textBox4, 1, 3);
-            this.tableLayoutPanel1.Location = new System.Drawing.Point(12, 12);
+            this.tableLayoutPanel1.Location = new System.Drawing.Point(22, 12);
             this.tableLayoutPanel1.Name = "tableLayoutPanel1";
-            this.tableLayoutPanel1.RowCount = 4;
+            this.tableLayoutPanel1.RowCount = 5;
+            this.tableLayoutPanel1.RowStyles.Add(new System.Windows.Forms.RowStyle());
             this.tableLayoutPanel1.RowStyles.Add(new System.Windows.Forms.RowStyle());
             this.tableLayoutPanel1.RowStyles.Add(new System.Windows.Forms.RowStyle());
             this.tableLayoutPanel1.RowStyles.Add(new System.Windows.Forms.RowStyle());
             this.tableLayoutPanel1.RowStyles.Add(new System.Windows.Forms.RowStyle());
-            this.tableLayoutPanel1.RowStyles.Add(new System.Windows.Forms.RowStyle(System.Windows.Forms.SizeType.Absolute, 20F));
-            this.tableLayoutPanel1.RowStyles.Add(new System.Windows.Forms.RowStyle(System.Windows.Forms.SizeType.Absolute, 20F));
-            this.tableLayoutPanel1.Size = new System.Drawing.Size(196, 104);
+            this.tableLayoutPanel1.Size = new System.Drawing.Size(203, 131);
             this.tableLayoutPanel1.TabIndex = 0;
             // 
+            // label5
+            // 
+            this.label5.Anchor = System.Windows.Forms.AnchorStyles.Right;
+            this.label5.AutoSize = true;
+            this.label5.Location = new System.Drawing.Point(12, 110);
+            this.label5.Name = "label5";
+            this.label5.Size = new System.Drawing.Size(58, 15);
+            this.label5.TabIndex = 8;
+            this.label5.Text = "Encryptor";
+            // 
             // label1
             // 
             this.label1.Anchor = System.Windows.Forms.AnchorStyles.Right;
             this.label1.AutoSize = true;
-            this.label1.Location = new System.Drawing.Point(12, 6);
+            this.label1.Location = new System.Drawing.Point(14, 5);
             this.label1.Name = "label1";
-            this.label1.Size = new System.Drawing.Size(51, 13);
+            this.label1.Size = new System.Drawing.Size(56, 15);
             this.label1.TabIndex = 0;
             this.label1.Text = "Server IP";
             // 
@@ -94,19 +108,33 @@
             // 
             this.label2.Anchor = System.Windows.Forms.AnchorStyles.Right;
             this.label2.AutoSize = true;
-            this.label2.Location = new System.Drawing.Point(3, 32);
+            this.label2.Location = new System.Drawing.Point(3, 31);
             this.label2.Name = "label2";
-            this.label2.Size = new System.Drawing.Size(60, 13);
+            this.label2.Size = new System.Drawing.Size(67, 15);
             this.label2.TabIndex = 1;
             this.label2.Text = "Server Port";
             // 
+            // comboBox1
+            // 
+            this.comboBox1.DropDownStyle = System.Windows.Forms.ComboBoxStyle.DropDownList;
+            this.comboBox1.FormattingEnabled = true;
+            this.comboBox1.ImeMode = System.Windows.Forms.ImeMode.NoControl;
+            this.comboBox1.ItemHeight = 13;
+            this.comboBox1.Items.AddRange(new object[] {
+            "table",
+            "rc4"});
+            this.comboBox1.Location = new System.Drawing.Point(76, 107);
+            this.comboBox1.Name = "comboBox1";
+            this.comboBox1.Size = new System.Drawing.Size(124, 21);
+            this.comboBox1.TabIndex = 9;
+            // 
             // label3
             // 
             this.label3.Anchor = System.Windows.Forms.AnchorStyles.Right;
             this.label3.AutoSize = true;
-            this.label3.Location = new System.Drawing.Point(10, 58);
+            this.label3.Location = new System.Drawing.Point(9, 57);
             this.label3.Name = "label3";
-            this.label3.Size = new System.Drawing.Size(53, 13);
+            this.label3.Size = new System.Drawing.Size(61, 15);
             this.label3.TabIndex = 2;
             this.label3.Text = "Password";
             // 
@@ -114,16 +142,16 @@
             // 
             this.label4.Anchor = System.Windows.Forms.AnchorStyles.Right;
             this.label4.AutoSize = true;
-            this.label4.Location = new System.Drawing.Point(8, 84);
+            this.label4.Location = new System.Drawing.Point(8, 83);
             this.label4.Name = "label4";
-            this.label4.Size = new System.Drawing.Size(55, 13);
+            this.label4.Size = new System.Drawing.Size(62, 15);
             this.label4.TabIndex = 3;
             this.label4.Text = "Proxy Port";
             // 
             // textBox1
             // 
             this.textBox1.Anchor = System.Windows.Forms.AnchorStyles.Left;
-            this.textBox1.Location = new System.Drawing.Point(69, 3);
+            this.textBox1.Location = new System.Drawing.Point(76, 3);
             this.textBox1.Name = "textBox1";
             this.textBox1.Size = new System.Drawing.Size(124, 20);
             this.textBox1.TabIndex = 4;
@@ -132,7 +160,7 @@
             // textBox2
             // 
             this.textBox2.Anchor = System.Windows.Forms.AnchorStyles.Left;
-            this.textBox2.Location = new System.Drawing.Point(69, 29);
+            this.textBox2.Location = new System.Drawing.Point(76, 29);
             this.textBox2.Name = "textBox2";
             this.textBox2.Size = new System.Drawing.Size(124, 20);
             this.textBox2.TabIndex = 5;
@@ -141,7 +169,7 @@
             // textBox3
             // 
             this.textBox3.Anchor = System.Windows.Forms.AnchorStyles.Left;
-            this.textBox3.Location = new System.Drawing.Point(69, 55);
+            this.textBox3.Location = new System.Drawing.Point(76, 55);
             this.textBox3.Name = "textBox3";
             this.textBox3.Size = new System.Drawing.Size(124, 20);
             this.textBox3.TabIndex = 6;
@@ -150,46 +178,12 @@
             // textBox4
             // 
             this.textBox4.Anchor = System.Windows.Forms.AnchorStyles.Left;
-            this.textBox4.Location = new System.Drawing.Point(69, 81);
+            this.textBox4.Location = new System.Drawing.Point(76, 81);
             this.textBox4.Name = "textBox4";
             this.textBox4.Size = new System.Drawing.Size(124, 20);
             this.textBox4.TabIndex = 7;
             this.textBox4.WordWrap = false;
             // 
-            // panel1
-            // 
-            this.panel1.Anchor = System.Windows.Forms.AnchorStyles.Top;
-            this.panel1.AutoSize = true;
-            this.panel1.AutoSizeMode = System.Windows.Forms.AutoSizeMode.GrowAndShrink;
-            this.panel1.Controls.Add(this.button2);
-            this.panel1.Controls.Add(this.button1);
-            this.panel1.Location = new System.Drawing.Point(59, 128);
-            this.panel1.Name = "panel1";
-            this.panel1.Size = new System.Drawing.Size(164, 30);
-            this.panel1.TabIndex = 1;
-            // 
-            // button2
-            // 
-            this.button2.DialogResult = System.Windows.Forms.DialogResult.Cancel;
-            this.button2.Location = new System.Drawing.Point(86, 4);
-            this.button2.Name = "button2";
-            this.button2.Size = new System.Drawing.Size(75, 23);
-            this.button2.TabIndex = 1;
-            this.button2.Text = "Cancel";
-            this.button2.UseVisualStyleBackColor = true;
-            this.button2.Click += new System.EventHandler(this.cancelButton_Click);
-            // 
-            // button1
-            // 
-            this.button1.DialogResult = System.Windows.Forms.DialogResult.OK;
-            this.button1.Location = new System.Drawing.Point(4, 4);
-            this.button1.Name = "button1";
-            this.button1.Size = new System.Drawing.Size(75, 23);
-            this.button1.TabIndex = 0;
-            this.button1.Text = "OK";
-            this.button1.UseVisualStyleBackColor = true;
-            this.button1.Click += new System.EventHandler(this.OKButton_Click);
-            // 
             // notifyIcon1
             // 
             this.notifyIcon1.ContextMenuStrip = this.contextMenuStrip1;
@@ -207,35 +201,79 @@
             this.QuitItem});
             this.contextMenuStrip1.Name = "contextMenuStrip1";
             this.contextMenuStrip1.RenderMode = System.Windows.Forms.ToolStripRenderMode.System;
-            this.contextMenuStrip1.Size = new System.Drawing.Size(111, 76);
+            this.contextMenuStrip1.Size = new System.Drawing.Size(123, 82);
             // 
             // ConfigItem
             // 
             this.ConfigItem.Font = new System.Drawing.Font("Segoe UI", 9F, System.Drawing.FontStyle.Bold);
             this.ConfigItem.Name = "ConfigItem";
-            this.ConfigItem.Size = new System.Drawing.Size(110, 22);
+            this.ConfigItem.Size = new System.Drawing.Size(122, 24);
             this.ConfigItem.Text = "Config";
             this.ConfigItem.Click += new System.EventHandler(this.Config_Click);
             // 
             // aboutToolStripMenuItem
             // 
             this.aboutToolStripMenuItem.Name = "aboutToolStripMenuItem";
-            this.aboutToolStripMenuItem.Size = new System.Drawing.Size(110, 22);
+            this.aboutToolStripMenuItem.Size = new System.Drawing.Size(122, 24);
             this.aboutToolStripMenuItem.Text = "About";
             this.aboutToolStripMenuItem.Click += new System.EventHandler(this.aboutToolStripMenuItem_Click);
             // 
             // toolStripSeparator2
             // 
             this.toolStripSeparator2.Name = "toolStripSeparator2";
-            this.toolStripSeparator2.Size = new System.Drawing.Size(107, 6);
+            this.toolStripSeparator2.Size = new System.Drawing.Size(119, 6);
             // 
             // QuitItem
             // 
             this.QuitItem.Name = "QuitItem";
-            this.QuitItem.Size = new System.Drawing.Size(110, 22);
+            this.QuitItem.Size = new System.Drawing.Size(122, 24);
             this.QuitItem.Text = "Quit";
             this.QuitItem.Click += new System.EventHandler(this.Quit_Click);
             // 
+            // panel2
+            // 
+            this.panel2.Anchor = System.Windows.Forms.AnchorStyles.Top;
+            this.panel2.AutoSize = true;
+            this.panel2.AutoSizeMode = System.Windows.Forms.AutoSizeMode.GrowAndShrink;
+            this.panel2.Location = new System.Drawing.Point(61, 175);
+            this.panel2.Name = "panel2";
+            this.panel2.Size = new System.Drawing.Size(0, 0);
+            this.panel2.TabIndex = 1;
+            // 
+            // button1
+            // 
+            this.button1.DialogResult = System.Windows.Forms.DialogResult.OK;
+            this.button1.Location = new System.Drawing.Point(4, 4);
+            this.button1.Name = "button1";
+            this.button1.Size = new System.Drawing.Size(75, 23);
+            this.button1.TabIndex = 0;
+            this.button1.Text = "OK";
+            this.button1.UseVisualStyleBackColor = true;
+            this.button1.Click += new System.EventHandler(this.OKButton_Click);
+            // 
+            // button2
+            // 
+            this.button2.DialogResult = System.Windows.Forms.DialogResult.Cancel;
+            this.button2.Location = new System.Drawing.Point(86, 4);
+            this.button2.Name = "button2";
+            this.button2.Size = new System.Drawing.Size(75, 23);
+            this.button2.TabIndex = 1;
+            this.button2.Text = "Cancel";
+            this.button2.UseVisualStyleBackColor = true;
+            this.button2.Click += new System.EventHandler(this.cancelButton_Click);
+            // 
+            // panel1
+            // 
+            this.panel1.Anchor = System.Windows.Forms.AnchorStyles.Top;
+            this.panel1.AutoSize = true;
+            this.panel1.AutoSizeMode = System.Windows.Forms.AutoSizeMode.GrowAndShrink;
+            this.panel1.Controls.Add(this.button2);
+            this.panel1.Controls.Add(this.button1);
+            this.panel1.Location = new System.Drawing.Point(61, 153);
+            this.panel1.Name = "panel1";
+            this.panel1.Size = new System.Drawing.Size(164, 30);
+            this.panel1.TabIndex = 1;
+            // 
             // Form1
             // 
             this.AcceptButton = this.button1;
@@ -245,6 +283,7 @@
             this.AutoSizeMode = System.Windows.Forms.AutoSizeMode.GrowAndShrink;
             this.CancelButton = this.button2;
             this.ClientSize = new System.Drawing.Size(282, 206);
+            this.Controls.Add(this.panel2);
             this.Controls.Add(this.tableLayoutPanel1);
             this.Controls.Add(this.panel1);
             this.Icon = ((System.Drawing.Icon)(resources.GetObject("$this.Icon")));
@@ -255,8 +294,8 @@
             this.Load += new System.EventHandler(this.Form1_Load);
             this.tableLayoutPanel1.ResumeLayout(false);
             this.tableLayoutPanel1.PerformLayout();
-            this.panel1.ResumeLayout(false);
             this.contextMenuStrip1.ResumeLayout(false);
+            this.panel1.ResumeLayout(false);
             this.ResumeLayout(false);
             this.PerformLayout();
 
@@ -273,15 +312,18 @@
         private System.Windows.Forms.TextBox textBox2;
         private System.Windows.Forms.TextBox textBox3;
         private System.Windows.Forms.TextBox textBox4;
-        private System.Windows.Forms.Panel panel1;
-        private System.Windows.Forms.Button button2;
-        private System.Windows.Forms.Button button1;
         private System.Windows.Forms.NotifyIcon notifyIcon1;
         private System.Windows.Forms.ContextMenuStrip contextMenuStrip1;
         private System.Windows.Forms.ToolStripMenuItem ConfigItem;
         private System.Windows.Forms.ToolStripMenuItem QuitItem;
         private System.Windows.Forms.ToolStripMenuItem aboutToolStripMenuItem;
         private System.Windows.Forms.ToolStripSeparator toolStripSeparator2;
+        private System.Windows.Forms.Label label5;
+        private System.Windows.Forms.ComboBox comboBox1;
+        private System.Windows.Forms.Panel panel2;
+        private System.Windows.Forms.Button button1;
+        private System.Windows.Forms.Button button2;
+        private System.Windows.Forms.Panel panel1;
     }
 }
 

shadowsocks-csharp/Form1.cs

@@ -32,6 +32,7 @@ namespace shadowsocks_csharp
             textBox2.Text = config.server_port.ToString();
             textBox3.Text = config.password;
             textBox4.Text = config.local_port.ToString();
+            comboBox1.Text = config.method == null ? "table" : config.method;
         }
 
         private void Form1_Load(object sender, EventArgs e)
@@ -77,6 +78,7 @@ namespace shadowsocks_csharp
                     server_port = int.Parse(textBox2.Text),
                     password = textBox3.Text,
                     local_port = int.Parse(textBox4.Text),
+                    method = comboBox1.Text,
                     isDefault = false
                 };
                 Config.Save(config);
@@ -102,7 +104,7 @@ namespace shadowsocks_csharp
 
         private void Form1_FormClosed(object sender, FormClosedEventArgs e)
         {
-            local.Stop();
+            if (local != null) local.Stop();
         }
 
         private void aboutToolStripMenuItem_Click(object sender, EventArgs e)

shadowsocks-csharp/Local.cs

@@ -16,7 +16,7 @@ namespace shadowsocks_csharp
         public Local(Config config)
         {
             this.config = config;
-            this.encryptor = new Encryptor(config.password);
+            this.encryptor = new Encryptor(config.method, config.password);
         }
 
         public void Start()
@@ -62,7 +62,11 @@ namespace shadowsocks_csharp
                 // Create the state object.
                 Handler handler = new Handler();
                 handler.connection = conn;
-                handler.encryptor = encryptor;
+                if (encryptor.method == Encryptor.TYPE_TABLE) {
+                    handler.encryptor = encryptor;
+                } else {
+                    handler.encryptor = new Encryptor(config.method, config.password);
+                }
                 handler.config = config;
 
                 handler.Start();

shadowsocks-csharp/RC4.cs

@@ -0,0 +1,70 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace shadowsocks_csharp
+{
+    public class RC4
+    {
+        class Context
+        {
+            public int index1 = 0;
+            public int index2 = 0;
+        }
+
+        private Context enc_ctx = new Context();
+        private Context dec_ctx = new Context();
+
+        public void Encrypt(byte[] table, byte[] data, int length)
+        {
+            EncryptOutput(enc_ctx, table, data, length);
+        }
+
+        public void Decrypt(byte[] table, byte[] data, int length)
+        {
+            EncryptOutput(dec_ctx, table, data, length);
+        }
+
+        public byte[] EncryptInitalize(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 EncryptOutput(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;
+        }
+    }
+}

shadowsocks-csharp/Test.cs

@@ -12,7 +12,7 @@ namespace shadowsocks_csharp
 
         public static void Test1()
         {
-            Encryptor encryptor = new Encryptor("foobar!");
+            Encryptor encryptor = new Encryptor("table", "foobar!");
 
             for (int i = 0; i < 256; i++)
             {

shadowsocks-csharp/shadowsocks-csharp.csproj

@@ -62,6 +62,7 @@
     <Reference Include="System.Windows.Forms" />
   </ItemGroup>
   <ItemGroup>
+    <Compile Include="RC4.cs" />
     <Compile Include="Config.cs" />
     <Compile Include="Encryptor.cs" />
     <Compile Include="Form1.cs">