COAUTHIDENTITY with CoSetProxyBlanket using JNA

Question

I am trying to write a Java API which uses JNA to communicate with WMI with remote machine (provided username and password).
For this I want to create COAUTHIDENTITY object and use it with CoSetProxyBlanket in Java.
The code I am trying to port is here.
Any help with this would be appreciated.

Answer 1

You can map the COAUTHIDENTITY structure in an interface class. It looks like WTypesBase which extends WTypes may be a good class name although you can put it anywhere.

The type mappings are simple: what you see as unsigned long can be NativeLong but since this is Windows-only code you can use int as we know it's 32-bit. The unsigned short * pointers are character arrays of 2-byte (wide) characters. Just use a Pointer for those.

So your structure heading should be:

class COAUTHIDENTITY extends Structure {
  public Pointer User;
  public int UserLength;
  public Pointer Domain;
  public int DomainLength;
  public Pointer Password;
  public int PasswordLength;
  public int Flags;
}

(Field order mappings are left as an exercise for the reader.)

Then to create it:

COAUTHIDENTITY auth = new COAUTHIDENTITY();

String user = "username"; // or get from the user
// Allocate memory for user including null terminator
auth.User = new Memory(Native.WCHAR_SIZE * (user.length() + 1));
// Set the widestring in memory
auth.User.setWideString(0, user);
auth.UserLength = user.length();

// Do the same for domain and password

auth.Flags = SEC_WINNT_AUTH_IDENTITY_ANSI;
// Note: SEC_WINNT_AUTH_IDENTITY_ANSI = 1