Silent login using Username in Azure Active Directory in Xamarin - xamarin

Question

I am developing app using Xamarin Forms. I have created a directory on azure portal. As i see references over internet , active directory authentication uses Microsofts login page to log in.
I want to create native login form and pass user name to active directory and authenticate it.
Is it possible to pass user credentials programatically and authenticate user?
How can i pass user credentials?
I have tried following but i got "(411) Length required" exception
var request = WebRequest.Create(string.Format(#"https://login.microsoftonline.com/{0}/oauth2/token?client_id=5e811f4f-4fa4-451e-a439-ca05cabc02d7&grant_type=password&username=02atul.com#gmail.com&password=userpassword&scope=openid", tenant));
request.ContentType = "application/x-www-form-urlencoded";
request.Method = "POST";
using (HttpWebResponse response = await request.GetResponseAsync() as HttpWebResponse)
{
if (response.StatusCode != HttpStatusCode.OK)
Debug.WriteLine("Error fetching data. Server returned status code: {0}", response.StatusCode);
using (StreamReader reader = new StreamReader(response.GetResponseStream()))
{
var content = reader.ReadToEnd();
if (string.IsNullOrWhiteSpace(content))
{
Debug.WriteLine("Response contained empty body...");
}
else {
Debug.WriteLine("Response Body: \r\n {0}", content);
}
}
}
My username is my email id. Is it correct user name? As i am getting bad request error now. What's missing?

Answer 1

Technically you could use username and password flow which is described in more detail here with ADAL.
However, you need to revisit your scenario and understand if it really accomplishes what the Azure Active Directory Platform is for.
Users use OAuth2 based authentication to get the security and safety of only having to share their passwords with trusted identity providers like MS, FB, Google, etc... In general, the safety conscious person will NOT want to type in a password into your random website, and trust that you do not abuse that information. If you want to use AAD, you should also use our login experiences, as this is really what the customer is paying for in our service in many regards.
EDIT: If ADAL no longer supports this flow, you can simply generate the http requests yourself:
POST: https://login.microsoftonline.com/xxxxx.onmicrosoft.com/oauth2/token
Content-Type: application/x-www-form-urlencoded
resource={resource}&client_id={clientId}&grant_type=password&username={userName}&password={password}&scope=openid&client_secret={clientSecret}