c# - ネットワーク共有ドライブにファイルをコピーする

Question

ファイルをコピーしたいネットワーク共有ドライブ ("\server\folder") があります。特定のユーザー（「ユーザー」/「パス」）でドライブに書き込むことができます。C# を使用して書き込み権限で共有ドライブにアクセスするにはどうすればよいですか?

Answer 1

テストされていないコードですが、次のようになります。

AppDomain.CurrentDomain.SetPrincipalPolicy(PrincipalPolicy.WindowsPrincipal);

// http://pinvoke.net/default.aspx/advapi32/LogonUser.html    
IntPtr token;
LogonUser("username", "domain", "password", LogonType.LOGON32_LOGON_BATCH, LogonProvider.LOGON32_PROVIDER_DEFAULT);

WindowsIdentity identity = new WindowsIdentity(token);

WindowsImpersonationContext context = identity.Impersonate();

try
{
    File.Copy(@"c:\temp\MyFile.txt", @"\\server\folder\Myfile.txt", true);
}
finally
{
    context.Undo();
}

Answer 2

ASP.NET アプリケーションの実際の例を次に示します。元のソース

private void SendToFileShare(byte[] pdfData, string fileName)
{
    if(pdfData == null)
    {
        throw new ArgumentNullException("pdfData");
    }
    if (string.IsNullOrWhiteSpace(fileName))
    {
        //Assign a unique name because the programmer failed to specify one.
        fileName = Guid.NewGuid().ToString();
    }
    else
    {
        //Should probably replace special characters (windows filenames) with something.                
    }


    string networkShareLocation = @"\\your\network\share\";

    var path = $"{networkShareLocation}{fileName}.pdf";


    //Credentials for the account that has write-access. Probably best to store these in a web.config file.
    var domain = "AB";
    var userID = "Mr";
    var password = "C";


    if (ImpersonateUser(domain, userID, password) == true)
    {
        //write the PDF to the share:
        System.IO.File.WriteAllBytes(path, report);

        undoImpersonation();
    }
    else
    {
        //Could not authenticate account. Something is up.
        //Log or something.
    }
}

/// <summary>
/// Impersonates the given user during the session.
/// </summary>
/// <param name="domain">The domain.</param>
/// <param name="userName">Name of the user.</param>
/// <param name="password">The password.</param>
/// <returns></returns>
private bool ImpersonateUser(string domain, string userName, string password)
{
    WindowsIdentity tempWindowsIdentity;
    IntPtr token = IntPtr.Zero;
    IntPtr tokenDuplicate = IntPtr.Zero;

    if (RevertToSelf())
    {
        if (LogonUserA(userName, domain, password, LOGON32_LOGON_INTERACTIVE,
            LOGON32_PROVIDER_DEFAULT, ref token) != 0)
        {
            if (DuplicateToken(token, 2, ref tokenDuplicate) != 0)
            {
                tempWindowsIdentity = new WindowsIdentity(tokenDuplicate);
                impersonationContext = tempWindowsIdentity.Impersonate();
                if (impersonationContext != null)
                {
                    CloseHandle(token);
                    CloseHandle(tokenDuplicate);
                    return true;
                }
            }
        }
    }
    if (token != IntPtr.Zero)
        CloseHandle(token);
    if (tokenDuplicate != IntPtr.Zero)
        CloseHandle(tokenDuplicate);
    return false;
}

/// <summary>
/// Undoes the current impersonation.
/// </summary>
private void undoImpersonation()
{
    impersonationContext.Undo();
}


#region Impersionation global variables
public const int LOGON32_LOGON_INTERACTIVE = 2;
public const int LOGON32_PROVIDER_DEFAULT = 0;

WindowsImpersonationContext impersonationContext;

[DllImport("advapi32.dll")]
public static extern int LogonUserA(String lpszUserName,
    String lpszDomain,
    String lpszPassword,
    int dwLogonType,
    int dwLogonProvider,
    ref IntPtr phToken);
[DllImport("advapi32.dll", CharSet = CharSet.Auto, SetLastError = true)]
public static extern int DuplicateToken(IntPtr hToken,
    int impersonationLevel,
    ref IntPtr hNewToken);

[DllImport("advapi32.dll", CharSet = CharSet.Auto, SetLastError = true)]
public static extern bool RevertToSelf();

[DllImport("kernel32.dll", CharSet = CharSet.Auto)]
public static extern bool CloseHandle(IntPtr handle);
#endregion

Answer 3

ネットワーク ドライブへの書き込み権限を持つユーザーを作成し、C# 内で偽装を使用して、ドライブにアクセスするときにそのユーザーを使用します。