static void Main(string[] args)
{
if (args.Length == 0)
{
Console.WriteLine("Usage: UnWak [FILE] [<path>]");
Console.WriteLine("Unpack wak file");
return;
}
byte[] wak_buffer = null;
try
{
using (FileStream wak_file = File.OpenRead(args[0]))
{
wak_buffer = new byte[wak_file.Length];
wak_file.Read(wak_buffer, 0, (int)wak_file.Length);
}
}
catch (Exception e)
{
Console.WriteLine($"Failed to read wak file: {e}");
Environment.Exit(-1);
}
FiletableEntry[] filetable = WakDecryptor.DecryptWak(wak_buffer);
Console.WriteLine($"Wak file decrypted, found {filetable.Length} files");
Console.Write("Unpacking... 0%");
string parent_path = args.Length > 1 ? args[1] : "";
for (int i = 0; i < filetable.Length; i++)
{
FiletableEntry filetable_entry = filetable[i];
string path = Path.Combine(parent_path, filetable_entry.filename);
try
{
Directory.CreateDirectory(Path.GetDirectoryName(path));
using (FileStream file = File.Create(path))
{
file.Write(wak_buffer, filetable_entry.file_offset, filetable_entry.file_size);
}
}
catch (Exception e)
{
Console.WriteLine($"\nFailed to write file {path}: {e}");
Environment.Exit(-1);
}
if (i % (filetable.Length / 100) == 0)
{
Console.Write($"\b\b\b\b{(100 * i / filetable.Length).ToString().PadLeft(3, ' ')}%");
}
}
Console.WriteLine("\b\b\b\b100%\nDone");
}
/// <summary>
/// Decrypts the specified wak file and copies the resulting data to the output byte array
/// </summary>
/// <param name="wak_file">The wak file to decrypt</param>
/// <param name="output">The output to which to write the decrypted file</param>
/// <returns></returns>
static public FiletableEntry[] DecryptWak(byte[] wak_file, byte[] output)
{
byte[] key = new byte[16];
byte[] IV = new byte[16];
GenerateIV(key, Constants.wak_key_seed);
GenerateIV(IV, Constants.wak_header_IV_seed);
Aes128CounterMode aes = new Aes128CounterMode(IV);
ICryptoTransform ict = aes.CreateDecryptor(key, null);
ict.TransformBlock(wak_file, 0, 16, output, 0); // decrypt header
int num_files = BinaryPrimitives.ReadInt32LittleEndian(new ReadOnlySpan <byte>(output, 4, 4));
int files_offset = BinaryPrimitives.ReadInt32LittleEndian(new ReadOnlySpan <byte>(output, 8, 4));
FiletableEntry[] fileTable = new FiletableEntry[num_files];
GenerateIV(IV, Constants.wak_filetable_IV_seed);
ict.TransformBlock(wak_file, 16, files_offset - 16, output, 16); // decrypt filetable
int entry_offset = 16;
for (int i = 0; i < num_files; i++)
{
int file_offset = BinaryPrimitives.ReadInt32LittleEndian(new ReadOnlySpan <byte>(output, entry_offset, 4));
int file_size = BinaryPrimitives.ReadInt32LittleEndian(new ReadOnlySpan <byte>(output, entry_offset + 4, 4));
int filename_length = BinaryPrimitives.ReadInt32LittleEndian(new ReadOnlySpan <byte>(output, entry_offset + 8, 4));
string filename = Encoding.UTF8.GetString(new ReadOnlySpan <byte>(output, entry_offset + 12, filename_length));
GenerateIV(IV, i); // file IV
ict.TransformBlock(wak_file, file_offset, file_size, output, file_offset); // decrypt file
fileTable[i].file_offset = file_offset;
fileTable[i].file_size = file_size;
fileTable[i].filename = filename;
entry_offset += 12 + filename_length;
}
return(fileTable);
}
