v0.80.30

2023-01-06 22:33:59 +04:00
parent a3cf868dfb
commit 2b31232b30
178 changed files with 5213 additions and 23780 deletions
--- a/AssetStudio/Crypto/CNUnity.cs
+++ b/AssetStudio/Crypto/CNUnity.cs
@@ -0,0 +1,164 @@
+using System;
+using System.Text;
+using System.Security.Cryptography;
+
+namespace AssetStudio
+{
+    public class CNUnity
+    {
+        private const string Signature = "#$unity3dchina!@";
+
+        public static ICryptoTransform Encryptor;
+
+        public byte[] Index = new byte[0x10];
+        public byte[] Sub = new byte[0x10];
+
+        public CNUnity(EndianBinaryReader reader)
+        {
+            reader.ReadUInt32();
+
+            var infoBytes = reader.ReadBytes(0x10);
+            var infoKey = reader.ReadBytes(0x10);
+            reader.Position += 1;
+
+            var signatureBytes = reader.ReadBytes(0x10);
+            var signatureKey = reader.ReadBytes(0x10);
+            reader.Position += 1;
+
+            DecryptKey(signatureKey, signatureBytes);
+
+            var str = Encoding.UTF8.GetString(signatureBytes);
+            if (str != Signature)
+                throw new Exception("Invalid Signature !!");
+
+            DecryptKey(infoKey, infoBytes);
+
+            infoBytes = infoBytes.ToUInt4Array();
+            infoBytes.AsSpan(0, 0x10).CopyTo(Index);
+            var subBytes = infoBytes.AsSpan(0x10, 0x10);
+            for (var i = 0; i < subBytes.Length; i++)
+            {
+                var idx = (i % 4 * 4) + (i / 4);
+                Sub[idx] = subBytes[i];
+            }
+        }
+
+        public static bool SetKey(Entry entry)
+        {
+            try
+            {
+                using var aes = Aes.Create();
+                aes.Mode = CipherMode.ECB;
+                aes.Key = Encoding.UTF8.GetBytes(entry.Key);
+
+                Encryptor = aes.CreateEncryptor();
+            }
+            catch(Exception e)
+            {
+                Logger.Error($"[CNUnity] Invalid key !!\n{e.Message}");
+                return false;
+            }
+            return true;
+        }
+
+        public void DecryptBlock(Span<byte> bytes, int size, int index)
+        {
+            var offset = 0;
+            while (offset < size)
+            {
+                offset += Decrypt(bytes[offset..], index++, size - offset);
+            }
+        }
+
+        private void DecryptKey(byte[] key, byte[] data)
+        {
+            if (Encryptor != null)
+            {
+                key = Encryptor.TransformFinalBlock(key, 0, key.Length);
+                for (int i = 0; i < 0x10; i++)
+                    data[i] ^= key[i];
+            }
+        }
+
+        private int DecryptByte(Span<byte> bytes, ref int offset, ref int index)
+        {
+            var b = Sub[((index >> 2) & 3) + 4] + Sub[index & 3] + Sub[((index >> 4) & 3) + 8] + Sub[((byte)index >> 6) + 12];
+            bytes[offset] = (byte)((Index[bytes[offset] & 0xF] - b) & 0xF | 0x10 * (Index[bytes[offset] >> 4] - b));
+            b = bytes[offset];
+            offset++;
+            index++;
+            return b;
+        }
+
+        private int Decrypt(Span<byte> bytes, int index, int remaining)
+        {
+            var offset = 0;
+            
+            var curByte = DecryptByte(bytes, ref offset, ref index);
+            var byteHigh = curByte >> 4;
+            var byteLow = curByte & 0xF;
+
+            if (byteHigh == 0xF)
+            {
+                int b;
+                do
+                {
+                    b = DecryptByte(bytes, ref offset, ref index);
+                    byteHigh += b;
+                } while (b == 0xFF);
+            }
+
+            offset += byteHigh;
+
+            if (offset < remaining)
+            {
+                DecryptByte(bytes, ref offset, ref index);
+                DecryptByte(bytes, ref offset, ref index);
+                if (byteLow == 0xF)
+                {
+                    int b;
+                    do
+                    {
+                        b = DecryptByte(bytes, ref offset, ref index);
+                    } while(b == 0xFF);
+                }
+            }
+
+            return offset;
+        }
+
+        public record Entry
+        {
+            public string Name { get; private set; }
+            public string Key { get; private set; }
+
+            public Entry(string name, string key)
+            {
+                Name = name;
+                Key = key;
+            }
+
+            public bool Validate()
+            {
+                try
+                {
+                    var bytes = Encoding.UTF8.GetBytes(Key);
+                    if (bytes.Length != 0x10)
+                    {
+                        Logger.Warning($"[CNUnity] {this} has invalid key, size should be 16 bytes, skipping...");
+                        return false;
+                    }
+                }
+                catch(Exception e)
+                {
+                    Logger.Error($"[CNUnity] Error while adding {this}: {e.Message}");
+                    return false;
+                }
+                
+                return true;
+            }
+
+            public override string ToString() => $"{Name} ({Key})";
+        }
+    }
+}