ImpersonateLoggedOnUser doesn't appear to work

Question

After a successful call to both LogonUser and ImpersonateLoggedOnUser it doesn't appear that my process is running as the new user...

system("whoami");

prints out: Chris-PC\Chris

when it should be: Chris-PC\LimitedGuy

Is there a function I'm not calling or something?

My code:

if(argc == 6) // impersonate
  {

   printf("[~] Logging in as %ws\\\\%ws..\n", argv[3], argv[4]);
   if(!LogonUser(argv[4], argv[3], argv[5], LOGON32_LOGON_INTERACTIVE, LOGON32_PROVIDER_DEFAULT, &logonToken))
   {
    printf("[!] Failed to login as %ws. Error Code: %X\n", argv[4], GetLastError());
    return 1;
   }


   if(!ImpersonateLoggedOnUser(logonToken))
   {
    printf("[!] ImpersonateLoggedOnUser failed with error code: %X\n", GetLastError());
    return 1;
   }

   LoadUserProfile(logonToken, &plinfo);
   system("whoami");
   printf("[~] Login successful!\n");
}

Answer 1

When you use the system call a new process is created to execute the command but in Windows the new process is always created with the token from the parent process not the thread (unless you specifically use one of the CreateProcessAsUser, CreateProcessWithLogonW, etc. calls). So in your case 'whoami' is executed in the context of the original user not the one impersonating. To check the name of the user being impersonated call GetUserName.