clipc!GetOfflineDeviceUniqueID PoC.

getduid.cs

using System;
using System.Runtime.InteropServices;

enum RETRIEVAL_METHOD {
  ODUID_DEFAULT = 0,
  ODUID_TPM_EK,
  ODUID_UEFI_VARIABLE_TPM,
  ODUID_UEFI_VARIABLE_RANDOMSEED,
  ODUID_UEFI_DEV_LOCK_UNLOCK, // there is no code for this in clipsvc.dll, given the enum name, this could be Windows Phone only?
  ODUID_XBOX_CONSOLE_ID, // this should never be seen, with xbox one a different function is called to get the console ID
  ODUID_REGISTRY_ENTRY // "fan name", RS2+ only.
}

class GODUID {
  [DllImport("clipc.dll")]
  // HRESULT GetOfflineDeviceUniqueID(DWORD cbSalt, PBYTE pbSalt, RETRIEVAL_METHOD* oMethod,PDWORD pcbSystemId,PBYTE rgbSystemId,PDWORD unkLength,PVOID unkPtr);
  static extern int GetOfflineDeviceUniqueID(uint cbSalt, byte[] pbSalt, out RETRIEVAL_METHOD oMethod,ref uint pcbSystemId,byte[] rgbSystemId,uint unk1,uint unk2);
  
  public static void Main(string[] args) {
    RETRIEVAL_METHOD rm;
    uint cbSalt;
    byte[] pbSalt;
    if (args.Length > 0) {
      var arg = args[0];
      if ((arg.StartsWith("0x")) && ((arg.Length & 1) == 0)) {
        pbSalt = new byte[(arg.Length - 2) / 2];
        for (int i = 2; i < arg.Length; i += 2)
          pbSalt[(i / 2) - 1] = Convert.ToByte(arg.Substring(i, 2), 16);
      } else {
        pbSalt = System.Text.Encoding.ASCII.GetBytes(arg);
      }
      cbSalt = (uint)pbSalt.Length;
    } else {
      cbSalt = 0;
      pbSalt = new byte[0];
    }
    uint cbSystemId = 32;
    byte[] rgbSystemId = new byte[32];
    var res = GetOfflineDeviceUniqueID(cbSalt,pbSalt,out rm,ref cbSystemId,rgbSystemId,0,0);
    if (res < 0) throw new COMException("",res);
    Console.WriteLine("Got device-unique ID via method {0}",rm);
    foreach (var sidbyte in rgbSystemId) Console.Write(sidbyte.ToString("x2"));
    Console.WriteLine("");
  }
}

hay!
where can we chat?