KNM.LdapUserInfoHelper

A cross-platform .NET library for detecting the local LDAP/Active Directory user context and retrieving the user’s Security Identifier (SID/S-1-x-x). Made for easy use with Dependency Injection and zero external configuration.

Features

• Automatic Windows AD Discovery: Detects domain and controller from the environment—no configuration required
• SID Retrieval: Automatically obtains the Windows user’s Security Identifier (SID)
• Global Directory User Lookup: Query Active Directory for any user by SID or username
• Cross-platform: Works on Windows (Active Directory environments); provides safe fallback on other platforms
• Dependency Injection Ready: Register as singleton or scoped for easy integration

Quick Start

1. Registration (Program.cs)

builder.Services.AddSingleton<ILdapUserInfoProvider, LdapUserInfoProvider>();

2. Usage Example

public class MyService
{
    private readonly LdapUserInfo _ldapUserInfo;


    public MyService(ILdapUserInfoProvider ldapUserInfoProvider)
    {
        _ldapUserInfo = ldapUserInfoProvider.GetUserInfo();
    }

    public void PrintLdapUser()
    {
        if (_ldapUserInfo.LdapUser)
            Console.WriteLine($"LDAP/AD user detected. SID: {_ldapUserInfo.SsId}");
        else
            Console.WriteLine($"Not in domain or not a Windows/AD user. Result: {_ldapUserInfo.Result}");
    }
}

3. Directory User Lookup Example

public async Task LookupBySid(ILdapUserInfoProvider ldapProvider, string sid)
{
    var user = await ldapProvider.FindUserBySsIdAsync(sid); // Query by SID, not sAMAccountName
    if (user != null) Console.WriteLine(user.DisplayName);
}

4. Returned Data Models

public class LdapUserInfo
{
    public bool LdapUser { get; set; }
    public string SsId { get; set; } = string.Empty;
    public string? Result { get; set; } // Diagnostic message
}

public class DirectoryUser
{
    public string SsId { get; set; } = string.Empty;
    public string Name { get; set; } = string.Empty;
    public string Surname { get; set; } = string.Empty;
    public string UserName { get; set; } = string.Empty;
    public string DisplayName { get; set; } = string.Empty;
    public string Email { get; set; } = string.Empty;
    public bool AccountEnabled { get; set; }
}

How it Works

• On Windows:
  • Automatically discovers AD domain and controller
  • Extracts current user’s SID (WindowsIdentity.User.Value)
  • Performs LDAP global/query by SID (objectSid) or username (sAMAccountName) [with correct binary conversion for SID]
• On non-Windows platforms:
  • Always sets LdapUser = false and fills Result with an explanatory message

All logic/configuration is resolved automatically within the provider—no external config needed.

Licensing

Proprietary / Private Repository