FrameworkExtensions.DirectoryServices 1.0.0.43

Extensions to DirectoryServices

Extension methods for Active Directory account management and Windows impersonation, part of Hawkynt's .NET Framework Extensions.

Overview

This library provides extension methods for GroupPrincipal, UserPrincipal, and Principal that simplify common Active Directory operations such as resolving group memberships (including nested groups), looking up users by various identity attributes, querying LDAP group properties, and performing Windows user impersonation. Results are cached using thread-safe concurrent dictionaries for high-performance repeated lookups. On .NET 5+ all AD-related classes are annotated with [SupportedOSPlatform("windows")].

API Reference

GroupPrincipal Extensions (System.DirectoryServices.AccountManagement.GroupPrincipal)

Static class: GroupPrincipalExtensions

Principal Extensions (System.DirectoryServices.AccountManagement.Principal)

Static class: PrincipalExtensions

UserPrincipal Extensions (System.DirectoryServices.AccountManagement.UserPrincipal)

Static class: UserPrincipalExtensions

User Name Methods

User Lookup Methods

LDAP Group Methods

ILDAPGroup (interface)

Namespace: System.DirectoryServices.AccountManagement

Represents the full set of LDAP group attributes as defined in Active Directory schema. For attribute descriptions see selfADSI: Group Attributes.

ILDAPCache (interface)

Namespace: System.DirectoryServices.AccountManagement

Controls the LDAP directory entry cache behavior.

Impersonation (class)

Namespace: System.Security

Availability: .NET Framework only (excluded from .NET Core, .NET 5+, and .NET Standard)

An IDisposable class that performs Windows user impersonation via the Win32 LogonUser API and WindowsIdentity.Impersonate. The impersonation context is automatically reverted when the object is disposed.

Enumerations

Constructors

Methods

Usage Examples

Resolving all members of a group (including nested)

using System.DirectoryServices.AccountManagement;

using var context = new PrincipalContext(ContextType.Domain);
var group = GroupPrincipal.FindByIdentity(context, "Developers");
foreach (var member in group.GetAllMembers(allowCached: true))
  Console.WriteLine(member.SamAccountName);

Resolving users from a SAM account name (user or group)

using System.DirectoryServices.AccountManagement;

// Works for both users and groups
foreach (var user in PrincipalExtensions.ResolveUsersForSamAccountName("dev-team"))
  Console.WriteLine(user.EmailAddress);

Looking up a user by any name

using System.DirectoryServices.AccountManagement;

var user = UserPrincipalExtensions.FindFirstDomainUserByAnyName("John Smith");
if (user != null) {
  Console.WriteLine(user.GetFullName(surnameFirst: true)); // "Smith, John"
  Console.WriteLine(user.GetEmailAddress());               // "John Smith" <jsmith@example.com>
}

Querying LDAP groups

using System.DirectoryServices.AccountManagement;

using var context = new PrincipalContext(ContextType.Domain);
var user = UserPrincipal.FindByIdentity(context, "jdoe");

// Direct groups only
foreach (var group in user.GetLDAPGroups())
  Console.WriteLine(group.DisplayName);

// All groups including transitive memberships
foreach (var group in user.GetAllLDAPGroups())
  Console.WriteLine($"{group.DisplayName} ({group.DistinguishedName})");

Windows impersonation

using System.Security;

// Impersonate with current domain
using (new Impersonation("serviceaccount", "password123")) {
  File.ReadAllText(@"\\server\share\secret.txt");
}

// Impersonate with explicit domain and logon type
using (new Impersonation("MYDOMAIN", "admin", "p@ssw0rd", Impersonation.LogonType.NetworkCleartext)) {
  // Code runs as impersonated user
}
// Original identity is automatically restored

Installation

dotnet add package FrameworkExtensions.DirectoryServices

Dependencies

• Backports (project reference)
• Corlib.Extensions (project reference)
• System.DirectoryServices (framework reference / NuGet)
• System.DirectoryServices.AccountManagement (framework reference / NuGet)

License

LGPL 3.0 or later - See LICENSE for details