diff --git a/shadowsocks-csharp/Encryption/Sodium.cs b/shadowsocks-csharp/Encryption/Sodium.cs
index 5e0d20d1..96f3673a 100755
--- a/shadowsocks-csharp/Encryption/Sodium.cs
+++ b/shadowsocks-csharp/Encryption/Sodium.cs
@@ -42,9 +42,15 @@ static Sodium()
         [DllImport(DLLNAME, CallingConvention = CallingConvention.Cdecl)]
         public extern static void crypto_stream_salsa20_xor_ic(byte[] c, byte[] m, ulong mlen, byte[] n, ulong ic, byte[] k);
 
+        [DllImport(DLLNAME, CallingConvention = CallingConvention.Cdecl)]
+        public extern static void crypto_stream_xsalsa20_xor_ic(byte[] c, byte[] m, ulong mlen, byte[] n, ulong ic, byte[] k);
+
         [DllImport(DLLNAME, CallingConvention = CallingConvention.Cdecl)]
         public extern static void crypto_stream_chacha20_xor_ic(byte[] c, byte[] m, ulong mlen, byte[] n, ulong ic, byte[] k);
 
+        [DllImport(DLLNAME, CallingConvention = CallingConvention.Cdecl)]
+        public extern static void crypto_stream_xchacha20_xor_ic(byte[] c, byte[] m, ulong mlen, byte[] n, ulong ic, byte[] k);
+
         [DllImport(DLLNAME, CallingConvention = CallingConvention.Cdecl)]
         public extern static int crypto_stream_chacha20_ietf_xor_ic(byte[] c, byte[] m, ulong mlen, byte[] n, uint ic, byte[] k);
     }
diff --git a/shadowsocks-csharp/Encryption/SodiumEncryptor.cs b/shadowsocks-csharp/Encryption/SodiumEncryptor.cs
index b1e2f3f5..523e1276 100755
--- a/shadowsocks-csharp/Encryption/SodiumEncryptor.cs
+++ b/shadowsocks-csharp/Encryption/SodiumEncryptor.cs
@@ -10,6 +10,8 @@ public class SodiumEncryptor
         const int CIPHER_SALSA20 = 1;
         const int CIPHER_CHACHA20 = 2;
         const int CIPHER_CHACHA20_IETF = 3;
+        const int CIPHER_XSALSA20 = 4 + 1;
+        const int CIPHER_XCHACHA20 = 4 + 2;
 
         const int SODIUM_BLOCK_SIZE = 64;
 
@@ -37,6 +39,12 @@ public SodiumEncryptor(string method, string password)
                 case CIPHER_CHACHA20:
                     encryptor_delegate = Sodium.crypto_stream_chacha20_xor_ic;
                     break;
+                case CIPHER_XSALSA20:
+                    encryptor_delegate = Sodium.crypto_stream_xsalsa20_xor_ic;
+                    break;
+                case CIPHER_XCHACHA20:
+                    encryptor_delegate = Sodium.crypto_stream_xchacha20_xor_ic;
+                    break;
                 case CIPHER_CHACHA20_IETF:
                     encryptor_delegate = crypto_stream_chacha20_ietf_xor_ic;
                     break;
@@ -46,6 +54,8 @@ public SodiumEncryptor(string method, string password)
         private static Dictionary<string, EncryptorInfo> _ciphers = new Dictionary<string, EncryptorInfo> {
                 {"salsa20", new EncryptorInfo(32, 8, true, CIPHER_SALSA20)},
                 {"chacha20", new EncryptorInfo(32, 8, true, CIPHER_CHACHA20)},
+                {"xsalsa20", new EncryptorInfo(32, 24, true, CIPHER_XSALSA20)},
+                {"xchacha20", new EncryptorInfo(32, 24, true, CIPHER_XCHACHA20)},
                 {"chacha20-ietf", new EncryptorInfo(32, 12, true, CIPHER_CHACHA20_IETF)},
         };