NTLM authentication not working in Linux based environment #101058
Description
Description
I need to send an http request to a server which uses Windows authentication. I wrote the following code to try and send just any request to my server.
var handler = new HttpClientHandler
{
PreAuthenticate = true,
UseProxy = false,
UseDefaultCredentials = false,
Credentials = new CredentialCache
{
{
new Uri("http://otherapi"), "Negotiate", new NetworkCredential("username", "password")
}
}
}
using var client = new HttpClient(handler);
var stringContent = new StringContent("{}", Encoding.UTF8, "application/json");
using var request = new HttpRequestMessage(HttpMethod.Post, "http://otherapi/api/endpoint");
request.Content = stringContent;
using var res = await client.SendAsync(request);
Console.WriteLine($"{res.StatusCode}");When running the above code on a Windows machine, everything works as expected, and BadRequest gets printed to the console ( which is what I expect to happen when sending an invalid json request ).
The problem is, I need to run this code on a Linux based machine, and when running it on an Ubuntu 22 machine (as well as the official aspnet docker image), it fails and prints out to the console Unauthorized, which means the windows authentication didn't work.
I also tried it with
Credentials = new CredentialCache
{
{
new Uri("http://otherapi"), "NTLM", new NetworkCredential("username", "password")
}
}with no success.
I opened up Wireshark on my windows machine to try and figure out whats going on. I saw that the client initially sends a POST request to the server, and then the server responds with a 401, and the following headers
WWW-Authenticate: Negotiate
WWW-Authenticate: NTLM
After that I saw that the client sent the same request again, this time with an Authorization header, which from what I understand, is the correct behaviour. After that the request continues as expected.
The problem is, when I open Wireshark on my Ubuntu machine, I see that after the server responded with the first 401, the client just stops sending requests for some reason.
Reproduction Steps
Run the following code in a Linux machine
var handler = new HttpClientHandler
{
PreAuthenticate = true,
UseProxy = false,
UseDefaultCredentials = false,
Credentials = new CredentialsCache
{
{
new Uri("http://otherapi"), "Negotiate", new NetworkCredential("username", "password")
}
}
}
using var client = new HttpClient(handler);
var stringContent = new StringContent("{}", Encoding.UTF8, "application/json");
using var request = new HttpRequestMessage(HttpMethod.Post, "http://otherapi/api/endpoint");
request.Content = stringContent;
using var res = await client.SendAsync(request);
Console.WriteLine($"{res.StatusCode}");Expected behavior
BadRequest printed out on both Linux and Windows
Actual behavior
Unauthorized printed out on Linux,
BadRequest printed out on Windows.
Regression?
No response
Known Workarounds
No response
Configuration
I tried both .NET 7 and .NET 8
Ran on Windows 10
Linux was ran on Ubuntu 22 and the official aspnet docker image
Other information
No response