FTP User Isolation <userIsolation>

Overview

The <userIsolation> element is used to start or restrict FTP clients in specific sections of an FTP site. Depending on the options that are specified in the <userIsolation> element, server administrators can prevent unauthorized access between users in a shared server environment where a single FTP site is shared between mutiple user accounts.

FTP user isolation was introduced in IIS 6.0, but has been significantly updated in FTP 7.0 and FTP 7.5. All of the previous FTP user isolation features remain available for backward compatibility, but the following options are now possible for the user isolation mode:

Mode	Description
None	Specifying this mode in FTP 7.0 and FTP 7.5 will configure user isolation to always start a FTP clients in the root of the FTP site. (This was not possible in IIS 6.0.) Note: If they have sufficient permissions, any FTP user can potentially access the content of any other FTP user within that FTP site.
StartInUsersDirectory	In IIS 6.0, if a directory existed with the same name as a user account and user isolation was disabled, FTP clients would start in the directory for the user name. This is still possible in FTP 7.0 and FTP 7.5 by specifying StartInUsersDirectory for the mode. Note: If they have sufficient permissions, any FTP user can potentially access the content of any other FTP user within that FTP site.
IsolateRootDirectoryOnly	In IIS 6.0, it was possible to use global virtual directories if you enabled user isolation and created physical directories for users to start in when they first logged on to the server. If you wanted to share content between a number of FTP users, you could create global virtual directories. This option is still available in FTP 7.0 and FTP 7.5 by specifying IsolateRootDirectoryOnly for the mode.
IsolateAllDirectories	When specifying this mode in FTP 7.0 and FTP 7.5, FTP clients will start in a directory that matches the name of their user account when they first logon to the server. By using this mode, you can use virtual directories for each of these accounts; you are no longer required to create a physical directory. (This was not possible in IIS 6.0.) However, if you use this option, you can no longer use global virtual directories. To share a folder between multiple FTP users, you must create a virtual directory to the global path for each user.
ActiveDirectory	When specifying this mode in FTP 7.0 and FTP 7.5, the FTP service will retrieve the user isolation settings from each user's account in their Active Directory settings; this mode works the same as IIS 6.0.
Custom	With FTP 7.5, you can now specify Custom for the user isolation mode. This mode allows you to use FTP extensibility to provide custom user isolation by creating a custom FTP provider.

When using either the IsolateRootDirectoryOnly or IsolateAllDirectories modes for user isolation, the physical or virtual directory paths must use the following hierarchy:

User Account Types	Home Directory Syntax
Anonymous users	%FtpRoot%\LocalUser\Public
Local Windows user accounts (Requires Basic authentication)	%FtpRoot%\LocalUser\%UserName%
Windows domain accounts (Requires Basic authentication)	%FtpRoot%\%UserDomain%\%UserName%
IIS Manager or ASP.NET custom authentication user accounts	%FtpRoot%\LocalUser\%UserName%

Compatibility

Version	Notes
IIS 10.0	The <userIsolation> element was not modified in IIS 10.0.
IIS 8.5	The <userIsolation> element was not modified in IIS 8.5.
IIS 8.0	The <userIsolation> element was not modified in IIS 8.0.
IIS 7.5	The <userIsolation> element of the <ftpServer> element ships as a feature of IIS 7.5.
IIS 7.0	The <userIsolation> element of the <ftpServer> element was introduced in FTP 7.0, which was a separate download for IIS 7.0.
IIS 6.0	N/A

Note

The FTP 7.0 and FTP 7.5 services shipped out-of-band for IIS 7.0, which required downloading and installing the modules from the following URL:

https://www.iis.net/expand/FTP

With Windows 7 and Windows Server 2008 R2, the FTP 7.5 service ships as a feature for IIS 7.5, so downloading the FTP service is no longer necessary.

Setup

To support FTP publishing for your Web server, you must install the FTP service. To do so, use the following steps.

Windows Server 2012 or Windows Server 2012 R2

1. On the taskbar, click Server Manager.

2. In Server Manager, click the Manage menu, and then click Add Roles and Features.

3. In the Add Roles and Features wizard, click Next. Select the installation type and click Next. Select the destination server and click Next.

4. On the Server Roles page, expand Web Server (IIS), and then select FTP Server.

   Note

   To support ASP.Membership authentication or IIS Manager authentication for the FTP service, you will need to select FTP Extensibility, in addition to FTP Service.
   .

5. Click Next, and then on the Select features page, click Next again.

6. On the Confirm installation selections page, click Install.

7. On the Results page, click Close.

Windows 8 or Windows 8.1

1. On the Start screen, move the pointer all the way to the lower left corner, right-click the Start button, and then click Control Panel.

2. In Control Panel, click Programs and Features, and then click Turn Windows features on or off.

3. Expand Internet Information Services, and then select FTP Server.

   Note

   To support ASP.Membership authentication or IIS Manager authentication for the FTP service, you will also need to select FTP Extensibility.
   

4. Click OK.

5. Click Close.

Windows Server 2008 R2

1. On the taskbar, click Start, point to Administrative Tools, and then click Server Manager.

2. In the Server Manager hierarchy pane, expand Roles, and then click Web Server (IIS).

3. In the Web Server (IIS) pane, scroll to the Role Services section, and then click Add Role Services.

4. On the Select Role Services page of the Add Role Services Wizard, expand FTP Server.

5. Select FTP Service.

   Note

   To support ASP.Membership authentication or IIS Manager authentication for the FTP service, you will also need to select FTP Extensibility.
   

6. Click Next.

7. On the Confirm Installation Selections page, click Install.

8. On the Results page, click Close.

Windows 7

1. On the taskbar, click Start, and then click Control Panel.

2. In Control Panel, click Programs and Features, and then click Turn Windows Features on or off.

3. Expand Internet Information Services, and then FTP Server.

4. Select FTP Service.

   Note

   To support ASP.Membership authentication or IIS Manager authentication for the FTP service, you will also need to select FTP Extensibility.
   

5. Click OK.

Windows Server 2008 or Windows Vista

1. Download the installation package from the following URL:

   • https://www.iis.net/expand/FTP

2. Follow the instructions in the following walkthrough to install the FTP service:

   • Installing and Troubleshooting FTP 7

How To

How to isolate users in virtual directories

1. Open Internet Information Services (IIS) Manager:

   • If you are using Windows Server 2012 or Windows Server 2012 R2:

     • On the taskbar, click Server Manager, click Tools, and then click Internet Information Services (IIS) Manager.

   • If you are using Windows 8 or Windows 8.1:

     • Hold down the Windows key, press the letter X, and then click Control Panel.
     • Click Administrative Tools, and then double-click Internet Information Services (IIS) Manager.

   • If you are using Windows Server 2008 or Windows Server 2008 R2:

     • On the taskbar, click Start, point to Administrative Tools, and then click Internet Information Services (IIS) Manager.

   • If you are using Windows Vista or Windows 7:

     • On the taskbar, click Start, and then click Control Panel.
     • Double-click Administrative Tools, and then double-click Internet Information Services (IIS) Manager.

2. In the Connections pane, expand the server name, expand the Sites node, then click the name of the site.

3. In the site's Home pane, double-click FTP User Isolation.
   

4. On the FTP User Isolation page, under Isolate users. Restrict users to the following directory:, select User name directory (disable global virtual directories).
   

5. In the Actions pane, click Apply.

---

How to isolate users using Active Directory

1. Open Internet Information Services (IIS) Manager:

   • If you are using Windows Server 2012 or Windows Server 2012 R2:

     • On the taskbar, click Server Manager, click Tools, and then click Internet Information Services (IIS) Manager.

   • If you are using Windows 8 or Windows 8.1:

     • Hold down the Windows key, press the letter X, and then click Control Panel.
     • Click Administrative Tools, and then double-click Internet Information Services (IIS) Manager.

   • If you are using Windows Server 2008 or Windows Server 2008 R2:

     • On the taskbar, click Start, point to Administrative Tools, and then click Internet Information Services (IIS) Manager.

   • If you are using Windows Vista or Windows 7:

     • On the taskbar, click Start, and then click Control Panel.
     • Double-click Administrative Tools, and then double-click Internet Information Services (IIS) Manager.

2. In the Connections pane, expand the server name, expand the Sites node, and then click the name of the site.

3. In the site's Home pane, double-click FTP User Isolation.
   

4. On the FTP User Isolation page, under Isolate users. Restrict users to the following directory:, select FTP home directory configured in Active Directory and then click Set.
   

5. In the Set Credentials dialog box, enter a user name and password in the User name and Password boxes. Enter the password again in the Confirm Password box, and then click OK.

6. In the Actions pane, click Apply.

For additional information about how to set up the Active Directory, see the "Isolate Users Using Active Directory Mode" section in the Hosting Multiple FTP Sites with FTP User Isolation (IIS 6.0) topic.

Configuration

The <userIsolation> element is configured at the site level.

Attributes

Attribute

Description

mode

Optional enum attribute. Specifies the user isolation mode. Name Description StartInUsersDirectory Specifies that user isolation should not be used, but start a session in user's directory if it exists. The numeric value is 0. IsolateRootDirectoryOnly Specifies that user isolation should isolate only the root directory. Users' home directories must be physical directories, and global virtual directories can still be used. The numeric value is 1. ActiveDirectory Isolates users based on Active Directory settings. The numeric value is 2. IsolateAllDirectories Specifies that user isolation should isolate all directories. User's home directories can be either physical directories or virtual directories, but global virtual directories are ignored; all virtual directories must be explicitly created under each user's home path. The numeric value is 3. None Specifies that no user isolation should not be used. The numeric value is 4. Custom Specifies that a custom FTP provider will implement the user isolation. The numeric value is 5. The default value is None.

Child Elements

Element	Description
activeDirectory	Optional element. Specifies the connection credentials and time-out for communicating with an Active Directory server.

Configuration Sample

The following sample displays a <userIsolation> element for an FTP site that configures the FTP service to use Active Directory for user isolation that site, and configures the credentials for the connection to the Active Directory server.

<site name="ftp.example.com" id="5">
  <application path="/">
    <virtualDirectory path="/" physicalPath="c:\inetpub\www.example.com" />
  </application>
  <bindings>
    <binding protocol="ftp" bindingInformation="*:21:" />
  </bindings>
  <ftpServer>
    <userIsolation mode="ActiveDirectory">
      <activeDirectory adUserName="MyUser"
        adPassword="[enc:RsaProtectedConfigurationProvider:57686f6120447564652c2049495320526f636b73:enc]"
        adCacheRefresh="00:02:00" />
    </userIsolation>
    <security>
      <authentication>
        <basicAuthentication enabled="true" />
        <anonymousAuthentication enabled="false" />
      </authentication>
    </security>
  </ftpServer>
</site>

Sample Code

The following examples configure Active Directory user isolation for an FTP site.

AppCmd.exe

appcmd.exe set config  -section:system.applicationHost/sites /[name='ftp.example.com'].ftpServer.userIsolation.mode:"ActiveDirectory" /commit:apphost
appcmd.exe set config  -section:system.applicationHost/sites /[name='ftp.example.com'].ftpServer.userIsolation.activeDirectory.adUserName:"MyUser" /[name='ftp.example.com'].ftpServer.userIsolation.activeDirectory.adPassword:"MyPassword" /[name='ftp.example.com'].ftpServer.userIsolation.activeDirectory.adCacheRefresh:"00:02:00" /commit:apphost

Note

You must be sure to set the commit parameter to apphost when you use AppCmd.exe to configure these settings. This commits the configuration settings to the appropriate location section in the ApplicationHost.config file.

C#

using System;
using System.Text;
using Microsoft.Web.Administration;

internal static class Sample {

    private static void Main() {
        
        using(ServerManager serverManager = new ServerManager()) { 
            Configuration config = serverManager.GetApplicationHostConfiguration();
            
            ConfigurationSection sitesSection = config.GetSection("system.applicationHost/sites");
            
            ConfigurationElementCollection sitesCollection = sitesSection.GetCollection();
            
            ConfigurationElement siteElement = FindElement(sitesCollection, "site", "name", @"ftp.example.com");
            if (siteElement == null) throw new InvalidOperationException("Element not found!");

            ConfigurationElement ftpServerElement = siteElement.GetChildElement("ftpServer");
            
            ConfigurationElement userIsolationElement = ftpServerElement.GetChildElement("userIsolation");
            userIsolationElement["mode"] = @"ActiveDirectory";
            
            ConfigurationElement activeDirectoryElement = userIsolationElement.GetChildElement("activeDirectory");
            activeDirectoryElement["adUserName"] = @"MyUser";
            activeDirectoryElement["adPassword"] = @"MyPassword";
            activeDirectoryElement["adCacheRefresh"] = TimeSpan.Parse("00:02:00");
            
            serverManager.CommitChanges();
        }
    }
    
       private static ConfigurationElement FindElement(ConfigurationElementCollection collection, string elementTagName, params string[] keyValues)
   {
      foreach (ConfigurationElement element in collection)
      {
         if (String.Equals(element.ElementTagName, elementTagName, StringComparison.OrdinalIgnoreCase))
         {
            bool matches = true;
            for (int i = 0; i < keyValues.Length; i += 2)
            {
               object o = element.GetAttributeValue(keyValues[i]);
               string value = null;
               if (o != null)
               {
                  value = o.ToString();
               }
               if (!String.Equals(value, keyValues[i + 1], StringComparison.OrdinalIgnoreCase))
               {
                  matches = false;
                  break;
               }
            }
            if (matches)
            {
               return element;
            }
         }
      }
      return null;
   }
}

VB.NET

Imports System
Imports System.Text
Imports Microsoft.Web.Administration

Module Sample
   Sub Main()
      Dim serverManager As ServerManager = New ServerManager
      Dim config As Configuration = serverManager.GetApplicationHostConfiguration
      Dim sitesSection As ConfigurationSection = config.GetSection("system.applicationHost/sites")
      Dim sitesCollection As ConfigurationElementCollection = sitesSection.GetCollection

      Dim siteElement As ConfigurationElement = FindElement(sitesCollection, "site", "name", "ftp.example.com")
      If (siteElement Is Nothing) Then
         Throw New InvalidOperationException("Element not found!")
      End If

      Dim ftpServerElement As ConfigurationElement = siteElement.GetChildElement("ftpServer")

      Dim userIsolationElement As ConfigurationElement = ftpServerElement.GetChildElement("userIsolation")
      userIsolationElement("mode") = "ActiveDirectory"

      Dim activeDirectoryElement As ConfigurationElement = userIsolationElement.GetChildElement("activeDirectory")
      activeDirectoryElement("adUserName") = "MyUser"
      activeDirectoryElement("adPassword") = "MyPassword"
      activeDirectoryElement("adCacheRefresh") = TimeSpan.Parse("00:02:00")

      serverManager.CommitChanges()
   End Sub

   Private Function FindElement(ByVal collection As ConfigurationElementCollection, ByVal elementTagName As String, ByVal ParamArray keyValues() As String) As ConfigurationElement
      For Each element As ConfigurationElement In collection
         If String.Equals(element.ElementTagName, elementTagName, StringComparison.OrdinalIgnoreCase) Then
            Dim matches As Boolean = True
            Dim i As Integer
            For i = 0 To keyValues.Length - 1 Step 2
               Dim o As Object = element.GetAttributeValue(keyValues(i))
               Dim value As String = Nothing
               If (Not (o) Is Nothing) Then
                  value = o.ToString
               End If
               If Not String.Equals(value, keyValues((i + 1)), StringComparison.OrdinalIgnoreCase) Then
                  matches = False
                  Exit For
               End If
            Next
            If matches Then
               Return element
            End If
         End If
      Next
      Return Nothing
   End Function


End Module

JavaScript

var adminManager = new ActiveXObject('Microsoft.ApplicationHost.WritableAdminManager');
adminManager.CommitPath = "MACHINE/WEBROOT/APPHOST";

var sitesSection = adminManager.GetAdminSection("system.applicationHost/sites", "MACHINE/WEBROOT/APPHOST");
var sitesCollection = sitesSection.Collection;
var siteElementPos = FindElement(sitesCollection, "site", ["name", "ftp.example.com"]);
if (siteElementPos == -1) throw "Element not found!";

var siteElement = sitesCollection.Item[siteElementPos]);
var ftpServerElement = siteElement.ChildElements.Item("ftpServer");
var userIsolationElement = ftpServerElement.ChildElements.Item("userIsolation");
userIsolationElement.Properties.Item("mode").Value = "ActiveDirectory";
var activeDirectoryElement = userIsolationElement.ChildElements.Item("activeDirectory");

activeDirectoryElement.Properties.Item("adUserName").Value = "MyUser";
activeDirectoryElement.Properties.Item("adPassword").Value = "MyPassword";
activeDirectoryElement.Properties.Item("adCacheRefresh").Value = "00:02:00";
adminManager.CommitChanges();

function FindElement(collection, elementTagName, valuesToMatch) {
   for (var i = 0; i < collection.Count; i++) {
      var element = collection.Item(i);
      if (element.Name == elementTagName) {
         var matches = true;
         for (var iVal = 0; iVal < valuesToMatch.length; iVal += 2) {
            var property = element.GetPropertyByName(valuesToMatch[iVal]);
            var value = property.Value;
            if (value != null) {
               value = value.toString();
            }
            if (value != valuesToMatch[iVal + 1]) {
               matches = false;
               break;
            }
         }
         if (matches) {
            return i;
         }
      }
   }
   return -1;
}

VBScript

Set adminManager = createObject("Microsoft.ApplicationHost.WritableAdminManager")
adminManager.CommitPath = "MACHINE/WEBROOT/APPHOST"
Set sitesSection = adminManager.GetAdminSection("system.applicationHost/sites", "MACHINE/WEBROOT/APPHOST")
Set sitesCollection = sitesSection.Collection

siteElementPos = FindElement(sitesCollection, "site", Array("name", "ftp.example.com"))
If siteElementPos = -1 Then
   WScript.Echo "Element not found!"
   WScript.Quit
End If

Set siteElement = sitesCollection.Item(siteElementPos)
Set ftpServerElement = siteElement.ChildElements.Item("ftpServer")
Set userIsolationElement = ftpServerElement.ChildElements.Item("userIsolation")
userIsolationElement.Properties.Item("mode").Value = "ActiveDirectory"
Set activeDirectoryElement = userIsolationElement.ChildElements.Item("activeDirectory")

activeDirectoryElement.Properties.Item("adUserName").Value = "MyUser"
activeDirectoryElement.Properties.Item("adPassword").Value = "MyPassword"
activeDirectoryElement.Properties.Item("adCacheRefresh").Value = "00:02:00"

adminManager.CommitChanges()

Function FindElement(collection, elementTagName, valuesToMatch)
   For i = 0 To CInt(collection.Count) - 1
      Set element = collection.Item(i)
      If element.Name = elementTagName Then
         matches = True
         For iVal = 0 To UBound(valuesToMatch) Step 2
            Set property = element.GetPropertyByName(valuesToMatch(iVal))
            value = property.Value
            If Not IsNull(value) Then
               value = CStr(value)
            End If
            If Not value = CStr(valuesToMatch(iVal + 1)) Then
               matches = False
               Exit For
            End If
         Next
         If matches Then
            Exit For
         End If
      End If
   Next
   If matches Then
      FindElement = i
   Else
      FindElement = -1
   End If
End Function