ArtsTech.AspnetCore.Authentication.Ntlm

An AspnetCore middleware for NTLM auth on Posix

Requirements

• Samba and Winbind installed
• Samba joined to AD
• Winbindd service running
• ntlm_auth accessible on PATH

Optional

• Samba Winbind Client libraries (include PrimarySid claim and GroupSid claims)

Configuration of Samba/Winbind is out of scope of this readme (and its quite beyond me).

Usage

Claims

This library will return a ClaimsPrinciple with a ClaimsIdentity.

The ClaimsIdentity will have the following claims:

- ClaimTypes.Name
- ClaimTypes.PrimarySid (Optional requires libwbclient)
- ClaimTypes.GroupSid (Optional requires libwbclient)

**Note, we only return GroupSid for user's direct membership. We do not recursively search for user's group membership yet.

You can instead use an IClaimsTransformation to search LDAP for group memberships recursively.

Dotnet 6 Minimal API example

using ArtsTech.AspnetCore.Authentication.Ntlm;
var builder = WebApplication.CreateBuilder(args);   
builder.Services
     .AddRazorPages()
     .AddAuthentication(NtlmDefaults.AuthenticationScheme)
     .AddNtlm();

builder.Services.AddAuthorization();

var app = builder.Build();
app.UseStaticFiles();

app.UseRouting();

app.UseAuthentication();
app.UseAuthorization();

app.MapRazorPages();

app.Run();