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/Mr0kUtils.cs
+++ b/AssetStudio/Crypto/Mr0kUtils.cs
@@ -0,0 +1,72 @@
+using System;
+using System.Buffers;
+using System.Buffers.Binary;
+
+namespace AssetStudio
+{
+    public static class Mr0kUtils
+    {
+        private const int BlockSize = 0x400;
+
+        private static readonly byte[] mr0kMagic = { 0x6D, 0x72, 0x30, 0x6B };
+        public static Span<byte> Decrypt(Span<byte> data, Mr0k mr0k)
+        {
+            var key1 = new byte[0x10];
+            var key2 = new byte[0x10];
+            var key3 = new byte[0x10];
+
+            data.Slice(4, 0x10).CopyTo(key1);
+            data.Slice(0x74, 0x10).CopyTo(key2);
+            data.Slice(0x84, 0x10).CopyTo(key3);
+
+            var encryptedBlockSize = Math.Min(0x10 * ((data.Length - 0x94) >> 7), BlockSize);
+
+            if (!mr0k.InitVector.IsNullOrEmpty())
+            {
+                for (int i = 0; i < mr0k.InitVector.Length; i++)
+                    key2[i] ^= mr0k.InitVector[i];
+            }
+
+            if (!mr0k.SBox.IsNullOrEmpty())
+            {
+                for (int i = 0; i < 0x10; i++)
+                    key1[i] = mr0k.SBox[(i % 4 * 0x100) | key1[i]];
+            }
+
+            AES.Decrypt(key1, mr0k.ExpansionKey);
+            AES.Decrypt(key3, mr0k.ExpansionKey);
+
+            for (int i = 0; i < key1.Length; i++)
+            {
+                key1[i] ^= key3[i];
+            }
+
+            key1.CopyTo(data.Slice(0x84, 0x10));
+
+            var seed1 = BinaryPrimitives.ReadUInt64LittleEndian(key2);
+            var seed2 = BinaryPrimitives.ReadUInt64LittleEndian(key3);
+            var seed = seed2 ^ seed1 ^ (seed1 + (uint)data.Length - 20);
+
+            var encryptedBlock = data.Slice(0x94, encryptedBlockSize);
+            var seedSpan = BitConverter.GetBytes(seed);
+            for (var i = 0; i < encryptedBlockSize; i++)
+            {
+                encryptedBlock[i] ^= (byte)(seedSpan[i % seedSpan.Length] ^ mr0k.BlockKey[i % mr0k.BlockKey.Length]);
+            }
+
+            data = data[0x14..];
+
+            if (!mr0k.PostKey.IsNullOrEmpty())
+            {
+                for (int i = 0; i < 0xC00; i++)
+                {
+                    data[i] ^= mr0k.PostKey[i % mr0k.PostKey.Length];
+                }
+            }
+
+            return data;
+        }
+
+        public static bool IsMr0k(ReadOnlySpan<byte> data) => data[..4].SequenceEqual(mr0kMagic);
+    }
+}