我的简单功能

 private bool IsValidActiveDirectoryUser(string activeDirectoryServerDomain, string username, string password)
    {
        try
        {
            DirectoryEntry de = new DirectoryEntry("LDAP://" + activeDirectoryServerDomain, username + "@" + activeDirectoryServerDomain, password, AuthenticationTypes.Secure);
            DirectorySearcher ds = new DirectorySearcher(de);
            ds.FindOne();
            return true;
        }
        catch //(Exception ex)
        {
            return false;
        }
    }

我的简单功能

 private bool IsValidActiveDirectoryUser(string activeDirectoryServerDomain, string username, string password)
    {
        try
        {
            DirectoryEntry de = new DirectoryEntry("LDAP://" + activeDirectoryServerDomain, username + "@" + activeDirectoryServerDomain, password, AuthenticationTypes.Secure);
            DirectorySearcher ds = new DirectorySearcher(de);
            ds.FindOne();
            return true;
        }
        catch //(Exception ex)
        {
            return false;
        }
    }

Windows身份验证失败的原因有很多:用户名或密码不正确、帐户被锁定、密码过期等等。为了区分这些错误，通过P/Invoke调用LogonUser API函数，如果函数返回false，检查错误代码:

using System;
using System.ComponentModel;
using System.Runtime.InteropServices;

using Microsoft.Win32.SafeHandles;

public static class Win32Authentication
{
    private class SafeTokenHandle : SafeHandleZeroOrMinusOneIsInvalid
    {
        private SafeTokenHandle() // called by P/Invoke
            : base(true)
        {
        }

        protected override bool ReleaseHandle()
        {
            return CloseHandle(this.handle);
        }
    }

    private enum LogonType : uint
    {
        Network = 3, // LOGON32_LOGON_NETWORK
    }

    private enum LogonProvider : uint
    {
        WinNT50 = 3, // LOGON32_PROVIDER_WINNT50
    }

    [DllImport("kernel32.dll", SetLastError = true)]
    private static extern bool CloseHandle(IntPtr handle);

    [DllImport("advapi32.dll", SetLastError = true)]
    private static extern bool LogonUser(
        string userName, string domain, string password,
        LogonType logonType, LogonProvider logonProvider,
        out SafeTokenHandle token);

    public static void AuthenticateUser(string userName, string password)
    {
        string domain = null;
        string[] parts = userName.Split('\\');
        if (parts.Length == 2)
        {
            domain = parts[0];
            userName = parts[1];
        }

        SafeTokenHandle token;
        if (LogonUser(userName, domain, password, LogonType.Network, LogonProvider.WinNT50, out token))
            token.Dispose();
        else
            throw new Win32Exception(); // calls Marshal.GetLastWin32Error()
    }
}

示例用法:

try
{
    Win32Authentication.AuthenticateUser("EXAMPLE\\user", "P@ssw0rd");
    // Or: Win32Authentication.AuthenticateUser("user@example.com", "P@ssw0rd");
}
catch (Win32Exception ex)
{
    switch (ex.NativeErrorCode)
    {
        case 1326: // ERROR_LOGON_FAILURE (incorrect user name or password)
            // ...
        case 1327: // ERROR_ACCOUNT_RESTRICTION
            // ...
        case 1330: // ERROR_PASSWORD_EXPIRED
            // ...
        case 1331: // ERROR_ACCOUNT_DISABLED
            // ...
        case 1907: // ERROR_PASSWORD_MUST_CHANGE
            // ...
        case 1909: // ERROR_ACCOUNT_LOCKED_OUT
            // ...
        default: // Other
            break;
    }
}

注意:LogonUser需要与您验证的域建立信任关系。

这里介绍的几个解决方案缺乏区分错误用户/密码和需要更改的密码的能力。这可以通过以下方式来实现:

using System;
using System.DirectoryServices.Protocols;
using System.Net;

namespace ProtocolTest
{
    class Program
    {
        static void Main(string[] args)
        {
            try
            {
                LdapConnection connection = new LdapConnection("ldap.fabrikam.com");
                NetworkCredential credential = new NetworkCredential("user", "password");
                connection.Credential = credential;
                connection.Bind();
                Console.WriteLine("logged in");
            }
            catch (LdapException lexc)
            {
                String error = lexc.ServerErrorMessage;
                Console.WriteLine(lexc);
            }
            catch (Exception exc)
            {
                Console.WriteLine(exc);
            }
        }
    }
}

如果用户密码错误，或者用户不存在，error将包含

“8009030C: LdapErr: DSID-0C0904DC，注释:AcceptSecurityContext错误，数据52e, v1db1”，

如果用户密码需要修改，则包含

"8009030C: LdapErr: DSID-0C0904DC，注释:AcceptSecurityContext错误，数据773,v1db1"

lexc。ServerErrorMessage数据值是Win32错误码的十六进制表示。这些是通过调用Win32 LogonUser API调用返回的相同错误代码。下面的列表总结了一些常见的十六进制和十进制值:

525​ user not found ​(1317)
52e​ invalid credentials ​(1326)
530​ not permitted to logon at this time​ (1328)
531​ not permitted to logon at this workstation​ (1329)
532​ password expired ​(1330)
533​ account disabled ​(1331) 
701​ account expired ​(1793)
773​ user must reset password (1907)
775​ user account locked (1909)

可能最简单的方法是PInvoke LogonUser Win32 api。

http://www.pinvoke.net/default.aspx/advapi32/LogonUser.html

MSDN参考在这里…

http://msdn.microsoft.com/en-us/library/aa378184.aspx

绝对要使用登录类型

LOGON32_LOGON_NETWORK (3)

这只创建了一个轻量级的令牌-完美的认证检查。(其他类型可用于构建交互式会话等)

另一个.NET调用用于快速验证LDAP凭据:

using System.DirectoryServices;

using(var DE = new DirectoryEntry(path, username, password)
{
    try
    {
        DE.RefreshCache(); // This will force credentials validation
    }
    catch (COMException ex)
    {
        // Validation failed - handle how you want
    }
}