public static async Task Main(string[] args)
{
var webHost = CreateWebHostBuilder(args).Build();
if (!RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
{
//await Task.Run(() => NGDP.LoadAllIndexes());
//Console.WriteLine("Loaded indexes");
var keys = await KeyService.LoadKeys();
Console.WriteLine("Loaded " + keys.Count + " keys");
}
await webHost.RunAsync();
}
// This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
public void Configure(IApplicationBuilder app, IHostingEnvironment env)
{
if (!RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
{
NGDP.LoadAllIndexes();
}
KeyService.LoadKeys();
if (env.IsDevelopment())
{
app.UseDeveloperExceptionPage();
}
app.UseResponseCompression();
app.UseCors("AllowSpecificOrigin");
app.UseMvc();
}
private static byte[] Decrypt(byte[] data, int index)
{
byte keyNameSize = data[1];
if (keyNameSize == 0 || keyNameSize != 8)
{
throw new Exception("keyNameSize == 0 || keyNameSize != 8");
}
byte[] keyNameBytes = new byte[keyNameSize];
Array.Copy(data, 2, keyNameBytes, 0, keyNameSize);
ulong keyName = BitConverter.ToUInt64(keyNameBytes, 0);
byte IVSize = data[keyNameSize + 2];
if (IVSize != 4 || IVSize > 0x10)
{
throw new Exception("IVSize != 4 || IVSize > 0x10");
}
byte[] IVpart = new byte[IVSize];
Array.Copy(data, keyNameSize + 3, IVpart, 0, IVSize);
if (data.Length < IVSize + keyNameSize + 4)
{
throw new Exception("data.Length < IVSize + keyNameSize + 4");
}
int dataOffset = keyNameSize + IVSize + 3;
byte encType = data[dataOffset];
if (encType != 'S' && encType != 'A') // 'S' or 'A'
{
throw new Exception("encType != ENCRYPTION_SALSA20 && encType != ENCRYPTION_ARC4");
}
dataOffset++;
// expand to 8 bytes
byte[] IV = new byte[8];
Array.Copy(IVpart, IV, IVpart.Length);
// magic
for (int shift = 0, i = 0; i < sizeof(int); shift += 8, i++)
{
IV[i] ^= (byte)((index >> shift) & 0xFF);
}
byte[] key = KeyService.GetKey(keyName);
if (key == null)
{
throw new KeyNotFoundException("Unknown keyname " + keyName.ToString("X16"));
}
if (encType == 'S')
{
ICryptoTransform decryptor = KeyService.SalsaInstance.CreateDecryptor(key, IV);
return(decryptor.TransformFinalBlock(data, dataOffset, data.Length - dataOffset));
}
else
{
// ARC4 ?
throw new Exception("encType ENCRYPTION_ARC4 not implemented");
}
}
