ActiveDirectoryMembershipProvider Class

Definition

Namespace:

System.Web.Security

Assembly:

System.Web.dll

Manages storage of membership information for an ASP.NET application in Active Directory and Active Directory Application Mode servers.

public ref class ActiveDirectoryMembershipProvider : System::Web::Security::MembershipProvider

public class ActiveDirectoryMembershipProvider : System.Web.Security.MembershipProvider

type ActiveDirectoryMembershipProvider = class
    inherit MembershipProvider

Public Class ActiveDirectoryMembershipProvider
Inherits MembershipProvider

Inheritance

Object

ProviderBase

MembershipProvider

ActiveDirectoryMembershipProvider

Examples

The following code examples show the Web.config file for an ASP.NET application configured to use an ActiveDirectoryMembershipProvider instance. The first example uses the default mappings for Active Directory attributes, and does not support password-reset security with question-and-answer nor the ability to call search methods. The second example shows all the attribute settings allowed for an ActiveDirectoryMembershipProvider instance.

The first example is a simple configuration file using default mappings for Active Directory attributes.

<configuration>
  <connectionStrings>
    <add name="ADService" connectionString="LDAP://ldapServer/" />
  </connectionStrings>
  <system.web>
    <membership defaultProvider="AspNetActiveDirectoryMembershipProvider">
      <providers>
        <add name="AspNetActiveDirectoryMembershipProvider"
          type="System.Web.Security.ActiveDirectoryMembershipProvider,
          System.Web, Version=2.0.3600, Culture=neutral,
          PublicKeyToken=b03f5f7f11d50a3a" />
      </providers>
    </membership>
  </system.web>
</configuration>

This example shows all of the attribute settings that are available for an instance of ActiveDirectoryMembershipProvider.

<configuration>
  <connectionStrings>
    <add name="ADService" connectionString="LDAP://ldapServer/" />
  </connectionStrings>
  <system.web>
    <membership
      defaultProvider="AspNetActiveDirectoryMembershipProvider">
      <providers>
        <add name="AspNetActiveDirectoryMembershipProvider"
          type="System.Web.Security.ActiveDirectoryMembershipProvider,
          System.Web, Version=1.0.3600, Culture=neutral,
          PublicKeyToken=b03f5f7f11d50a3a"
          connectionStringName="ADService"
          connectionUsername="UserWithAppropriateRights"
          connectionPassword="PasswordForUser"
          connectionProtection="Secure"
          enablePasswordReset="true"
          enableSearchMethods="true"
          requiresQuestionAndAnswer="true"
          applicationName="/"
          description="Default AD connection"
          requiresUniqueEmail="false"
          clientSearchTimeout="30"
          serverSearchTimeout="30"
          timeoutUnit="Minutes"
          attributeMapPasswordQuestion="department"
          attributeMapPasswordAnswer="division"
          attributeMapFailedPasswordAnswerCount="singleIntAttribute"
         attributeMapFailedPasswordAnswerTime="singleLargeIntAttribute"
         attributeMapFailedPasswordAnswerLockoutTime="singleLargeIntAttribute"
          attributeMapEmail = "mail"
          attributeMapUsername = "userPrincipalName"
          maxInvalidPasswordAttempts = "5"
          passwordAttemptWindow = "10"
          passwordAnswerAttemptLockoutDuration = "30"
          minRequiredPasswordLength="7"
          minRequiredNonalphanumericCharacters="1"
          passwordStrengthRegularExpression="
          @\"(?=.{6,})(?=(.*\d){1,})(?=(.*\W){1,})" />
        />
      </providers>
    </membership>
  </system.web>
</configuration>

clientSearchTimeout and serverSearchTimeout default to minutes. To change the units, set the timeoutUnit attribute value to one of "Days", "Hours", "Minutes", "Seconds", or "Milliseconds". If the attribute is not specified, the default is "Minutes".

Remarks

This class is used by the Membership and MembershipUser classes to provide membership services for an ASP.NET application using an Active Directory (AD) or Active Directory Application Mode (ADAM) server.

Note

Using an ADAM server requires specific configuration. For more information, see the ADAM Configuration section below.

Important

The ActiveDirectoryMembershipProvider instance works only in the full-trust policy default configuration of ASP.NET. In order to use the ActiveDirectoryMembershipProvider instance at any partial-trust level, either you must make changes to the appropriate trust policy file for your application or you must create a "sandbox" assembly that is deployed in the GAC.

The ActiveDirectoryMembershipProvider class requires unrestricted DirectoryServicesPermission permission to run. This permission is not added to any of the partial-trust policy files supplied with ASP.NET. Although adding the DirectoryServicesPermission permission to a partial-trust policy file will enable use of the ActiveDirectoryMembershipProvider class, doing so makes the System.DirectoryServices namespace classes available to any code running in your ASP.NET pages. This option is not recommended for any Web servers that need to run in a secure, locked-down mode.

As an alternative, you can create a "sandbox" assembly that calls the ActiveDirectoryMembershipProvider class. This assembly can contain either a wrapper class that forwards method calls to the ActiveDirectoryMembershipProvider class or a class that derives from the ActiveDirectoryMembershipProvider class. In either case, the wrapper class must assert unrestricted DirectoryServicesPermission permission. Deploy the sandbox assembly in the GAC and mark the assembly with the AllowPartiallyTrustedCallersAttribute (APTCA) attribute. This will enable your partially trusted ASP.NET code to call your wrapper class, and since the wrapper class internally asserts the unrestricted DirectoryServicesPermission permission, your wrapper class will be able to successfully call the provider

You must create a connectionStrings Element (ASP.NET Settings Schema) entry in the Web.config file that identifies the Active Directory server, Active Directory domain, or ADAM application partition to use. The provider will only operate at domain scope, or in a subscope within a domain. The following table lists allowed connection strings and the scope used.

Connection string	Scope
LDAP://<domain or server>:[port] Port number is optional for ADAM and not needed for Active Directory.	The provider runs against the specified domain or server. With AD, user creation and deletion is done in the default users container. All other operations, including any search methods, will be rooted at the default naming context for the domain. If the connection string specifies an Active Directory domain rather than a specific server and the EnablePasswordReset property is true, the ActiveDirectoryMembershipProvider instance will always connect to the server with the PDC role for the domain to ensure that password changes take effect and are available when the ValidateUser method is called. This connection string is not allowed when using ADAM, and will throw a NotSupportedException.
LDAP://<domain or server>:[port]/<container dn> Port number is optional for ADAM and not needed for Active Directory.	The provider runs against the specified domain or server. User creation and deletion is only done in the specified container. All other operations, including any search methods, perform subtree searches rooted at the container. For ADAM servers, the container specifies the root of an application partition, or a container within an application partition. We recommend that the connection string define a specific container to improve performance.

The ActiveDirectoryMembershipProvider instance maps directory attributes to ActiveDirectoryMembershipUser properties. Default attributes are used if no attribute mapping is done in the Web.config file. For more information on attribute mappings, see the individual properties in the ActiveDirectoryMembershipUser class documentation.

The following table lists the ActiveDirectoryMembershipUser properties and their default attribute mappings.

Important

The ActiveDirectoryMembershipProvider class does not explicitly check that provider attributes are not mapped to core attributes of the user object in the directory. You must ensure that sensitive information from the directory is not exposed through mapped attributes.

Property	Default directory attribute	Can be mapped?
ProviderUserKey	securityIdentifier	No
UserName	userPrincipalName	Yes, but must be either userPrincipalName or sAMAccountName
Comment	comment	No
CreationDate	whenCreated	No
Email	mail	Yes, but must be a single-valued attribute of type Unicode String.
LastActivityDate	n/a	Not supported by ActiveDirectoryMembershipProvider.
LastLoginDate	n/a	Not supported by ActiveDirectoryMembershipProvider.
LastPasswordChangedDate	pwdLastSet	No
PasswordQuestion	none	Yes, but must be a single-valued attribute of type Unicode String.
IsApproved	User-Account-Control (AD) mDS-UserAccountDisabled (ADAM)	No
IsLockedOut	computed from lockoutTime and the AD lockout duration (AD on Windows 2000) msDS-User-Account-Control-Computed (AD on Windows Server 2003) msDS-User-Account-Control-Computed (ADAM)	No
LastLockoutDate	If user is locked out due to too many bad password attempts, the lockout time attribute is returned. If user is locked out due to too many bad password answer attempts, the value stored in the attribute defined by attributeMapFailedPasswordAnswerLockoutTime is returned. If user is locked out due to both a bad password and too many bad password attempts, the most recent date/time value is returned. If the account is not locked out, return 1/1/1754 for SQL compatibility.	No

When both the RequiresQuestionAndAnswer and EnablePasswordReset properties are true, the ActiveDirectoryMembershipProvider class supports password-reset security by requiring the user to answer a predetermined question. To support the question and answer, you must set the following configuration attributes using the add Element for providers for membership (ASP.NET Settings Schema) in the application configuration file.

Configuration attribute	Attribute type
attributeMapPasswordQuestion	Must be a single-valued attribute of type Unicode String.
attributeMapPasswordAnswer	Must be a single-valued attribute of type Unicode String.
attributeMapFailedPasswordAnswerCount	Must be a single-valued attribute of type Integer.
attributeMapFailedPasswordAnswerTime	Must be a single-valued attribute of type Large Integer/Interval.
attributeMapFailedPasswordAnswerLockoutTime	Must be a single-valued attribute of type Large Integer/Interval.

For more information on using password-reset security, see the RequiresQuestionAndAnswer property.

Active Directory connections

When the ActiveDirectoryMembershipProvider class is used to connect to an Active Directory or an Active Directory Application Mode (ADAM) server, the connectionProtection attribute that is set using the add Element for providers for membership (ASP.NET Settings Schema) in the application configuration file may restrict the types of operations the ActiveDirectoryMembershipProvider class can perform over the connection. The connectionProtection attribute also determines the methods the ActiveDirectoryMembershipProvider instance will use to create the connection to the Active Directory or ADAM server.

The following table shows the effect of the connectionProtection attribute when connecting to an Active Directory.

connectionProtection setting	Effect
None	The ActiveDirectoryMembershipProvider class will connect to an Active Directory, with these restrictions. - Any method that sets a password will fail. Active Directory requires a secure connection when changing passwords. - You must explicitly set the connectionUsername and connectionPassword attributes using the add Element for providers for membership (ASP.NET Settings Schema) in the application configuration file; otherwise, the ActiveDirectoryMembershipProvider instance will throw a ProviderException exception.
Secure	The ActiveDirectoryMembershipProvider class will attempt to connect to Active Directory using SSL. If SSL fails, a second attempt to connect to Active Directory using sign-and-seal will be made. If both attempts fail, the ActiveDirectoryMembershipProvider instance will throw a ProviderException exception. Both process credentials and explicit credentials are supported.

The following table shows the effect of the connectionProtection attribute when connecting to an ADAM server.

connectionProtection setting	Effect
None	The ActiveDirectoryMembershipProvider class will connect to an ADAM server, with this restriction. - Any method that sets passwords will fail unless you explicitly configure the ADAM server to allow passwords to be sent and changed over an insecure connection. Both process credentials and explicit credentials are supported.
Secure	The ActiveDirectoryMembershipProvider class will attempt to connect to the ADAM server using SSL. If a connection cannot be made, the ActiveDirectoryMembershipProvider instance will throw a ProviderException exception. Both process credentials and explicit credentials are supported.

ADAM Configuration

When using an ADAM server, the ADAM instance must contain a schema that defines the User class. You can import the User class with an LDIF import of the MS-User.ldf file available in the ADAM install directory.

The ActiveDirectoryMembershipProvider class will work with an ADAM server configured to use the default network ports. The following table shows the defaults expected for the ADAM server.

connectionProtection setting	Expected ADAM port
None	389
Secure	636

Constructors

ActiveDirectoryMembershipProvider()

Creates a new instance of the ActiveDirectoryMembershipProvider class.

Properties

ApplicationName	The name of the application using the custom membership provider.
CurrentConnectionProtection	Gets the current level of security being used to protect communications with the server.
Description	Gets a brief, friendly description suitable for display in administrative tools or other user interfaces (UIs). (Inherited from ProviderBase)
EnablePasswordReset	Gets a value indicating whether the ActiveDirectoryMembershipProvider instance is configured to allow users to reset their passwords.
EnablePasswordRetrieval	Gets a value indicating whether the user's password can be retrieved from the Active Directory data store. This property always returns false.
EnableSearchMethods	Gets a value indicating whether search-oriented ActiveDirectoryMembershipProvider methods are available.
MaxInvalidPasswordAttempts	Gets the number of failed answer attempts a user is allowed for the password-reset question.
MinRequiredNonAlphanumericCharacters	Gets the minimum number of special characters that must be present in a valid password.
MinRequiredPasswordLength	Gets the minimum length required for a password.
Name	Gets the friendly name used to refer to the provider during configuration. (Inherited from ProviderBase)
PasswordAnswerAttemptLockoutDuration	Get the length of time for which a user account is locked out after the user makes too many bad password-answer attempts.
PasswordAttemptWindow	Gets the time window during which consecutive failed attempts to provide a valid password or a valid password answer are tracked.
PasswordFormat	Gets a value indicating the format of passwords in the Active Directory data store.
PasswordStrengthRegularExpression	Gets the regular expression used to evaluate a password.
RequiresQuestionAndAnswer	Gets a value indicating whether the membership provider is configured to require a password question and answer when creating a user.
RequiresUniqueEmail	Gets a value indicating whether an email address stored on the Active Directory server must be unique.

Methods

ChangePassword(String, String, String)	Changes the password for the specified user.
ChangePasswordQuestionAndAnswer(String, String, String, String)	Updates the password question and answer for a user in the Active Directory store.
CreateUser(String, String, String, String, String, Boolean, Object, MembershipCreateStatus)	Adds a new user to the Active Directory data store.
DecryptPassword(Byte[])	Decrypts an encrypted password. (Inherited from MembershipProvider)
DeleteUser(String, Boolean)	Removes a user's membership information from the Active Directory data store.
EncryptPassword(Byte[])	Encrypts a password. (Inherited from MembershipProvider)
EncryptPassword(Byte[], MembershipPasswordCompatibilityMode)	Encrypts the specified password using the specified password-compatibility mode. (Inherited from MembershipProvider)
Equals(Object)	Determines whether the specified object is equal to the current object. (Inherited from Object)
FindUsersByEmail(String, Int32, Int32, Int32)	Returns a collection of membership users from the Active Directory data store based on the user's email address.
FindUsersByName(String, Int32, Int32, Int32)	Returns a collection of users from the Active Directory data store based on the user name.
GeneratePassword()	Generates a random password.
GetAllUsers(Int32, Int32, Int32)	Gets a collection of all the users stored in an Active Directory data source.
GetHashCode()	Serves as the default hash function. (Inherited from Object)
GetNumberOfUsersOnline()	Throws a NotSupportedException exception in all cases.
GetPassword(String, String)	Returns the password of the specified user from the database. The ActiveDirectoryMembershipProvider class does not support this method.
GetType()	Gets the Type of the current instance. (Inherited from Object)
GetUser(Object, Boolean)	Gets the membership user information associated with the specified user key.
GetUser(String, Boolean)	Gets the membership user information associated with the specified user name.
GetUserNameByEmail(String)	Gets the user name associated with the specified email address.
Initialize(String, NameValueCollection)	Initializes the ActiveDirectoryMembershipProvider instance with the property values from the application's configuration files. This method is not intended to be called from your code.
MemberwiseClone()	Creates a shallow copy of the current Object. (Inherited from Object)
OnValidatingPassword(ValidatePasswordEventArgs)	Raises the ValidatingPassword event if an event handler has been defined. (Inherited from MembershipProvider)
ResetPassword(String, String)	Resets a user's password to a new, automatically generated password.
ToString()	Returns a string that represents the current object. (Inherited from Object)
UnlockUser(String)	Clears a lock so that a membership user can be validated.
UpdateUser(MembershipUser)	Updates information about a user in the Active Directory data store.
ValidateUser(String, String)	Verifies that the specified user name and password exist in the Active Directory data store.

Events

ValidatingPassword

Occurs when a user is created, a password is changed, or a password is reset. (Inherited from MembershipProvider)

See also

• Introduction to ASP.NET Membership
• How to: Use Membership in ASP.NET 2.0