From f0920098ad21a6cc7e2913a071f4e0bdb5c30f0b Mon Sep 17 00:00:00 2001
From: clowwindy <clowwindy42@gmail.com>
Date: Sat, 13 Dec 2014 10:15:15 +0800
Subject: [PATCH] sodium works

---
 shadowsocks-csharp/Encrypt/EncryptorBase.cs   |  2 ++
 .../Encrypt/EncryptorFactory.cs               |  2 +-
 shadowsocks-csharp/Encrypt/IVEncryptor.cs     |  2 +-
 shadowsocks-csharp/Encrypt/SodiumEncryptor.cs | 35 +++++++++++++++++--
 .../View/ConfigForm.Designer.cs               |  2 ++
 5 files changed, 38 insertions(+), 5 deletions(-)

diff --git a/shadowsocks-csharp/Encrypt/EncryptorBase.cs b/shadowsocks-csharp/Encrypt/EncryptorBase.cs
index eb8c1f37..06779103 100644
--- a/shadowsocks-csharp/Encrypt/EncryptorBase.cs
+++ b/shadowsocks-csharp/Encrypt/EncryptorBase.cs
@@ -6,6 +6,8 @@ namespace Shadowsocks.Encrypt
     public abstract class EncryptorBase
         : IEncryptor
     {
+        public const int MAX_INPUT_SIZE = 32768;
+
         protected EncryptorBase(string method, string password)
         {
             Method = method;
diff --git a/shadowsocks-csharp/Encrypt/EncryptorFactory.cs b/shadowsocks-csharp/Encrypt/EncryptorFactory.cs
index 59111a69..e62aed06 100644
--- a/shadowsocks-csharp/Encrypt/EncryptorFactory.cs
+++ b/shadowsocks-csharp/Encrypt/EncryptorFactory.cs
@@ -10,7 +10,7 @@ namespace Shadowsocks.Encrypt
                 return new TableEncryptor(method, password);
             }
 
-            return new PolarSSLEncryptor(method, password);
+            return new SodiumEncryptor(method, password);
         }
     }
 }
diff --git a/shadowsocks-csharp/Encrypt/IVEncryptor.cs b/shadowsocks-csharp/Encrypt/IVEncryptor.cs
index 66883918..bdeae866 100755
--- a/shadowsocks-csharp/Encrypt/IVEncryptor.cs
+++ b/shadowsocks-csharp/Encrypt/IVEncryptor.cs
@@ -8,7 +8,7 @@ namespace Shadowsocks.Encrypt
     public abstract class IVEncryptor
         : EncryptorBase
     {
-        protected static byte[] tempbuf = new byte[32768];
+        protected static byte[] tempbuf = new byte[MAX_INPUT_SIZE];
 
         protected Dictionary<string, int[]> ciphers;
 
diff --git a/shadowsocks-csharp/Encrypt/SodiumEncryptor.cs b/shadowsocks-csharp/Encrypt/SodiumEncryptor.cs
index d08027d7..277fb80f 100755
--- a/shadowsocks-csharp/Encrypt/SodiumEncryptor.cs
+++ b/shadowsocks-csharp/Encrypt/SodiumEncryptor.cs
@@ -10,15 +10,21 @@ namespace Shadowsocks.Encrypt
         const int CIPHER_SALSA20 = 1;
         const int CIPHER_CHACHA20 = 2;
 
-        protected uint _encryptBytesRemaining;
-        protected uint _decryptBytesRemaining;
+        const int SODIUM_BLOCK_SIZE = 64;
+
+        protected int _encryptBytesRemaining;
+        protected int _decryptBytesRemaining;
         protected ulong _encryptIC;
         protected ulong _decryptIC;
+        protected byte[] _encryptBuf;
+        protected byte[] _decryptBuf;
 
         public SodiumEncryptor(string method, string password)
             : base(method, password)
         {
             InitKey(method, password);
+            _encryptBuf = new byte[MAX_INPUT_SIZE + SODIUM_BLOCK_SIZE];
+            _decryptBuf = new byte[MAX_INPUT_SIZE + SODIUM_BLOCK_SIZE];
         }
 
         protected override Dictionary<string, int[]> getCiphers()
@@ -31,18 +37,41 @@ namespace Shadowsocks.Encrypt
 
         protected override void cipherUpdate(bool isCipher, int length, byte[] buf, byte[] outbuf)
         {
-            uint bytesRemaining;
+            // TODO write a unidirection cipher so we don't have to if if if
+            int bytesRemaining;
             ulong ic;
+            byte[] sodiumBuf;
+            byte[] iv;
             if (isCipher)
             {
                 bytesRemaining = _encryptBytesRemaining;
                 ic = _encryptIC;
+                sodiumBuf = _encryptBuf;
+                iv = _encryptIV;
             }
             else
             {
                 bytesRemaining = _decryptBytesRemaining;
                 ic = _decryptIC;
+                sodiumBuf = _decryptBuf;
+                iv = _decryptIV;
+            }
+            int padding = bytesRemaining;
+            Buffer.BlockCopy(buf, 0, sodiumBuf, padding, length);
+
+            switch (_cipher)
+            {
+                case CIPHER_SALSA20:
+                    Sodium.crypto_stream_salsa20_xor_ic(sodiumBuf, sodiumBuf, (ulong)(padding + length), iv, ic, _key);
+                    break;
+                case CIPHER_CHACHA20:
+                    Sodium.crypto_stream_chacha20_xor_ic(sodiumBuf, sodiumBuf, (ulong)(padding + length), iv, ic, _key);
+                    break;
             }
+            Buffer.BlockCopy(sodiumBuf, padding, outbuf, 0, length);
+            padding += length;
+            ic += (ulong)padding / SODIUM_BLOCK_SIZE;
+            bytesRemaining = padding % SODIUM_BLOCK_SIZE;
 
             if (isCipher)
             {
diff --git a/shadowsocks-csharp/View/ConfigForm.Designer.cs b/shadowsocks-csharp/View/ConfigForm.Designer.cs
index 50273d07..03b4a134 100755
--- a/shadowsocks-csharp/View/ConfigForm.Designer.cs
+++ b/shadowsocks-csharp/View/ConfigForm.Designer.cs
@@ -206,6 +206,8 @@
             this.EncryptionSelect.Items.AddRange(new object[] {
             "table",
             "rc4-md5",
+            "salsa20",
+            "chacha20",
             "aes-256-cfb",
             "aes-192-cfb",
             "aes-128-cfb",