Introduction
The previous two tutorials examined using forms authentication to identify website visitors. The forms authentication framework makes it easy for developers to log a user into a website and to remember them across page visits through the use of authentication tickets. TheFormsAuthentication
class includes methods
for generating the ticket and adding it to the visitor's cookies. The FormsAuthenticationModule
examines all incoming requests and, for those with a valid authentication ticket,
creates and associates a GenericPrincipal
and a FormsIdentity
object with the current request. Forms authentication is merely a mechanism for
granting an authentication ticket to a visitor when logging in and, on subsequent
requests, parsing that ticket to determine the user's identity. For a web application
to support user accounts, we still need to implement a user store and add functionality
to validate credentials, register new users, and the myriad of other user account-related
tasks.Prior to ASP.NET 2.0, developers were on the hook for implementing all of these user account-related tasks. Fortunately the ASP.NET team recognized this shortcoming and introduced the Membership framework with ASP.NET 2.0. The Membership framework is a set of classes in the .NET Framework that provide a programmatic interface for accomplishing core user account-related tasks. This framework is built atop the provider model, which allows developers to plug a customized implementation into a standardized API.
As discussed in the Security Basics and ASP.NET Support tutorial, the .NET Framework ships with two built-in Membership providers:
ActiveDirectoryMembershipProvider
and
SqlMembershipProvider
. As its name implies, the SqlMembershipProvider
uses a Microsoft SQL Server database as the user store. In order to use this provider
in an application, we need to tell the provider what database to use as the store.
As you might imagine, the SqlMembershipProvider
expects the user store
database to have certain database tables, views, and stored procedures. We need
to add this expected schema to the selected database.This tutorial starts by examining techniques for adding the necessary schema to the database in order to use the
SqlMembershipProvider
. Following that,
we will examine the key tables in the schema and discuss their purpose and importance.
This tutorial ends with a look at how to tell an ASP.NET application which provider
the Membership framework should use.Let's get started!
Step 1: Deciding Where to Place the User Store
An ASP.NET application's data is commonly stored in a number of tables in a database. When implementing theSqlMembershipProvider
database schema we must
decide whether to place the Membership schema in the same database as the application
data or in an alternate database.
I recommend locating the Membership schema in the same database as the application data for the following reasons:
- Maintainability � an application whose data is encapsulated in one database is easier to understand, maintain, and deploy than an application that has two separate databases.
- Relational Integrity � by locating the Membership-related tables in the same database as the application tables it is possible to establish foreign key constraints between the primary keys in the Membership-related tables and related application tables.
Creating a Database
The application we have been building since the second tutorial has not yet needed a database. We need one now, however, for the user store. Let's create one and then add to it the schema required by theSqlMembershipProvider
provider
(see Step 2).Note: Throughout this tutorial series we will be using a Microsoft SQL Server 2005 Express Edition database to store our application tables and the
SqlMembershipProvider
schema. This decision was made
for two reasons: first, due to its cost - free - the Express Edition is the most
readably accessible version of SQL Server 2005; second, SQL Server 2005 Express
Edition databases can be placed directly in the web application's App_Data
folder, making it a cinch to package the database and web application together in
one ZIP file and to redeploy it without any special setup instructions or configuration
options. If you'd prefer to follow along using a non-Express Edition version of
SQL Server, feel free. The steps are virtually identical. The SqlMembershipProvider
schema will work with any version of Microsoft SQL Server 2000 and up.From the Solution Explorer, right-click on the
App_Data
folder and
choose to Add New Item. (If you do not see an App_Data
folder in your
project, right-click on the project in Solution Explorer, select Add ASP.NET Folder,
and pick App_Data
.) From the Add New Item dialog box, choose to add
a new SQL Database named SecurityTutorials.mdf
. In this tutorial we
will add the SqlMembershipProvider
schema to this database; in subsequent
tutorials we will create additional tables to capture our application data.Adding a database to the
App_Data
folder automatically includes it
in the Database Explorer view. (In the non-Express Edition version of Visual Studio,
the Database Explorer is called the Server Explorer.) Go to the Database Explorer
and expand the just-added SecurityTutorials
database. If you do not
see the Database Explorer on screen, go to the View menu and choose Database Explorer,
or hit Ctrl+Alt+S. As Figure 2 shows, the SecurityTutorials
database
is empty - it contains no tables, no views, and no stored procedures.
Step 2: Adding the SqlMembershipProvider
Schema to the Database
The SqlMembershipProvider
requires a particular set of tables, views,
and stored procedures to be installed in the user store database. These requisite
database objects can be added using the
aspnet_regsql.exe
tool. This file is located in the %WINDIR%\Microsoft.Net\Framework\v2.0.50727\
folder.Note: The
aspnet_regsql.exe
tool offers both command line functionality
and a graphical user interface. The graphical interface is more user friendly and
is what we will examine in this tutorial. The command line interface is useful when
the addition of the SqlMembershipProvider
schema needs to be automated,
such as in build scripts or automated testing scenarios.The
aspnet_regsql.exe
tool is used to add or remove ASP.NET application
services to a specified SQL Server database. The ASP.NET application services
encompass the schemas for the SqlMembershipProvider
and SqlRoleProvider
,
along with the schemas for the SQL-based providers for other ASP.NET 2.0 frameworks.
We need to provide two bits of information to the aspnet_regsql.exe
tool:- Whether we want to add or remove application services, and
- The database from which to add or remove the application services schema
aspnet_regsql.exe
tool asks
us to provide the name of the server the database resides on, the security credentials
for connecting to the database, and the database name. If you are using the non-Express
Edition of SQL Server, you should already know this information, as it is the same
information you must provide through a connection string when working with the database
through an ASP.NET web page. Determining the server and database name when using
a SQL Server 2005 Express Edition database in the App_Data
folder,
however, is a bit more involved.The following section examines a straightforward way for specifying the server and database name for a SQL Server 2005 Express Edition database in the
App_Data
folder. If you are not using SQL Server 2005 Express Edition feel free to skip ahead
to the Installing the Application Services section.
Determining the Server and Database Name for a SQL Server 2005 Express Edition Database
in the App_Data
Folder
In order to use the aspnet_regsql.exe
tool we need to know the server
and database names. The server name is localhost\InstanceName
.
Most likely, the InstanceName is SQLExpress
. However, if you
installed SQL Server 2005 Express Edition manually (that is, you did not install
it automatically while installing Visual Studio), then it is possible that you selected
a different instance name.The database name is a bit trickier to determine. Databases in the
App_Data
folder typically have a database name that includes a
globally unique identifier along with the path to the database file. We
need to determine this database name in order to add the application services schema
through aspnet_regsql.exe
.The easiest way to ascertain the database name is to examine it through SQL Server Management Studio. SQL Server Management Studio provides a graphical interface for managing SQL Server 2005 databases, but it does not ship with the Express Edition of SQL Server 2005. The good news is that you can download the free Express Edition of SQL Server Management Studio.
Note: If you also have a non-Express Edition version of SQL Server 2005 installed on your desktop then the full version of Management Studio is likely installed. You can use the full version to determine the database name, following the same steps as outlined below for the Express Edition.
Start by closing Visual Studio to ensure that any locks imposed by Visual Studio on the database file are closed. Next, launch SQL Server Management Studio and connect to the
localhost\InstanceName
database for SQL Server 2005 Express
Edition. As noted earlier, chances are the instance name is SQLExpress
.
For the Authentication option, select Windows Authentication.After connecting to the SQL Server 2005 Express Edition instance, Management Studio displays folders for the Databases, the Security settings, the Server Objects, and so on. If you expand the Databases tab you will see that the
SecurityTutorials.mdf
database is not registered in the database instance - we need to attach the
database first.Right-click on the Databases folder and choose Attach from the context menu. This will display the Attach Databases dialog box. From here, click the Add button, browse to the
SecurityTutorials.mdf
database, and click OK. Figure 4 shows
the Attach Databases dialog box after the SecurityTutorials.mdf
database
has been selected. Figure 5 shows Management Studio's Object Explorer after the
database has been successfully attached.As Figure 5 shows, the
SecurityTutorials.mdf
database has a rather
abstruse name. Let's change it to a more memorable (and easier to type) name. Right-click
on the database, choose Rename from the context menu, and rename it SecurityTutorialsDatabase
.
This does not change the filename, just the name the database uses to identify itself
to SQL Server.At this point we know the server and database names for the
SecurityTutorials.mdf
database file: localhost\InstanceName
and SecurityTutorialsDatabase
,
respectively. We are now ready to install the application services through the
aspnet_regsql.exe
tool.Installing the Application Services
To launch theaspnet_regsql.exe
tool, go to the start menu and choose
Run. Enter %WINDIR%\Microsoft.Net\Framework\v2.0.50727\aspnet_regsql.exe
into the textbox and click OK. Alternatively, you can use Windows Explorer to drill
down to the appropriate folder and double-click the aspnet_regsql.exe
file. Either approach will net the same results.Running the
aspnet_regsql.exe
tool without any command line arguments
launches the ASP.NET SQL Server Setup Wizard graphical user interface. The wizard
makes it easy to add or remove the ASP.NET application services on a specified database.
The first screen of the wizard, shown in Figure 7, describes the purpose of the
tool.The second step in the wizard asks us whether we want to add the application services or remove them. Since we want to add the tables, views, and stored procedures necessary for the
SqlMembershipProvider
, choose the Configure SQL Server for
application services option. Later, if you want to remove this schema from your
database, re-run this wizard, but instead choose the Remove application services
information from an existing database option.The third step prompts for the database information: the server name, authentication information, and the database name. If you have been following along with this tutorial and have added the
SecurityTutorials.mdf
database to App_Data
,
attached it to localhost\InstanceName
, and renamed it to SecurityTutorialsDatabase
,
then use the following values:- Server:
localhost\InstanceName
- Windows authentication
- Database:
SecurityTutorialsDatabase
Note: If you used Management Studio to attach the database and rename the database file, be sure to detach the database and close Management Studio before reopening Visual Studio. To detach the
SecurityTutorialsDatabase
database,
right-click on the database name and, from the Tasks menu, choose Detach.Upon completion of the wizard, return to Visual Studio and navigate to the Database Explorer. Expand the Tables folder. You should see a series of tables whose names start with the prefix
aspnet_
. Likewise, a variety of views and stored
procedures can be found under the Views and Stored Procedures folders. These database
objects make up the application services schema. We will examine the membership-
and role-specific database objects in Step 3.Note: The
aspnet_regsql.exe
tool's graphical user interface
installs the entire application services schema. But when executing aspnet_regsql.exe
from the command-line you can specify what particular application services components
to install (or remove). Therefore, if you want to add just the tables, views, and
stored procedures necessary for the SqlMembershipProvider
and SqlRoleProvider
providers, run aspnet_regsql.exe
from the command-line. Alternatively,
you can manually run the appropriate subset of T-SQL create scripts used by aspnet_regsql.exe
.
These scripts are located in the WINDIR%\Microsoft.Net\Framework\v2.0.50727\
folder with names like InstallCommon.sql
, InstallMembership.sql
, InstallRoles.sql
,
InstallProfile.sql
, InstallSqlState.sql
, and so on.At this point we have created the database objects needed by the
SqlMembershipProvider
.
However, we still need to instruct the Membership framework that it should use the
SqlMembershipProvider
(versus, say, the ActiveDirectoryMembershipProvider
)
and that the SqlMembershipProvider
should use the SecurityTutorials
database. We'll look at how to specify what provider to use and how to customize
the selected provider's settings in Step 4. But first, let's take a deeper look
at the database objects that were just created.Step 3: A Look at the Schema's Core Tables
When working with the Membership and Roles frameworks in an ASP.NET application, the implementation details are encapsulated by the provider. In future tutorials we will interface with these frameworks via the .NET Framework'sMembership
and Roles
classes. When using these high-level APIs we do not need
to concern ourselves with the low-level details, like what queries are executed
or what tables are modified by the SqlMembershipProvider
and SqlRoleProvider
.
Given this, we could confidently use the Membership and Roles frameworks without having explored the database schema created in Step 2. However, when creating the tables to store application data we may need to create entities that relate to users or roles. It helps to have a familiarity with the
SqlMembershipProvider
and SqlRoleProvider
schemas when establishing foreign key constraints
between the application data tables and those tables created in Step 2. Moreover,
in certain rare circumstances we may need to interface with the user and role stores
directly at the database level (instead of through the Membership
or
Roles
classes).Partitioning the User Store Into Applications
The Membership and Roles frameworks are designed such that a single user and role store can be shared among many different applications. An ASP.NET application that uses the Membership or Roles frameworks must specify what application partition to use. In short, multiple web applications can use the same user and role stores. Figure 11 depicts user and role stores that are partitioned into three applications: HRSite, CustomerSite, and SalesSite. These three web applications each have their own unique users and roles, yet they all physically store their user account and role information in the same database tables.The
aspnet_Applications
table is what defines these partitions. Each
application that uses the database to store user account information is represented
by a row in this table. The aspnet_Applications
table has four columns:
ApplicationId
, ApplicationName
, LoweredApplicationName
,
and Description
. ApplicationId
is of type
uniqueidentifier
and is the table's primary key; ApplicationName
provides a unique human-friendly name for each application.The other Membership- and Role-related tables link back to the
ApplicationId
field in aspnet_Applications
. For example, the aspnet_Users
table, which contains a record for each user account, has an ApplicationId
foreign key field; ditto for the aspnet_Roles
table. The ApplicationId
field in these tables specifies the application partition the user account or role
belongs to.
Storing User Account Information
User account information is housed in two tables:aspnet_Users
and
aspnet_Membership
. The aspnet_Users
table contains fields
that hold the essential user account information. The three most pertinent columns
are:UserId
UserName
ApplicationId
UserId
is the primary key (and of type uniqueidentifier
).
UserName
is of type nvarchar(256)
and, along with the
password, makes up the user's credentials. (A user's password is stored in the
aspnet_Membership
table.) ApplicationId
links the user account
to a particular application in aspnet_Applications
. There is a composite
UNIQUE
constraint
on the UserName
and ApplicationId
columns. This ensures
that in a given application each UserName is unique, yet it allows for the same
UserName
to be used in different applications.The
aspnet_Membership
table includes additional user account information,
like the user's password, email address, the last login date and time, and so forth.
There is a one-to-one correspondence between records in the aspnet_Users
and aspnet_Membership
tables. This relationship is ensured by the
UserId
field in aspnet_Membership
, which serves as the table's
primary key. Like the aspnet_Users
table, aspnet_Membership
includes an ApplicationId
field that ties this information to a particular
application partition.Securing Passwords
Password information is stored in theaspnet_Membership
table. The
SqlMembershipProvider
allows for passwords to be stored in the database
using one of the following three techniques:- Clear - the password is stored in the database as plain-text. I strongly discourage using this option. If the database is compromised - be it by a hacker who finds a back door or a disgruntled employee who has database access - every single user's credentials are there for the taking.
- Hashed - passwords are hashed using a one-way hash algorithm and a randomly generated salt value. This hashed value (along with the salt) is stored in the database.
- Encrypted - an encrypted version of the password is stored in the database.
SqlMembershipProvider
settings specified in Web.config
. We will look at customizing the
SqlMembershipProvider
settings in Step 4. The default behavior is to
store the hash of the password.The columns responsible for storing the password are
Password
, PasswordFormat
,
and PasswordSalt
. PasswordFormat
is a field of type
int
whose value indicates the technique used for storing the password:
0 for Clear; 1 for Hashed; 2 for Encrypted. PasswordSalt
is assigned
a randomly generated string regardless of the password storage technique used; the
value of PasswordSalt
is only used when computing the hash of the password.
Finally, the Password
column contains the actual password data, be
it the plain-text password, the hash of the password, or the encrypted password.Table 1 illustrates what these three columns might look like for the various storage techniques when storing the password MySecret! .
Storage Technique<_o3a_p />
|
Password<_o3a_p />
|
PasswordFormat<_o3a_p />
|
PasswordSalt<_o3a_p />
|
Clear
|
MySecret!
|
0
|
tTnkPlesqissc2y2SMEygA==
|
Hashed
|
2oXm6sZHWbTHFgjgkGQsc2Ec9ZM=
|
1
|
wFgjUfhdUFOCKQiI61vtiQ==
|
Encrypted
|
62RZgDvhxykkqsMchZ0Yly7HS6onhpaoCYaRxV8g0F4CW56OXUU3e7Inza9j9BKp
|
2
|
LSRzhGS/aa/oqAXGLHJNBw==
|
SqlMembershipProvider
is determined by the settings in the <machineKey>
element. We
discussed this configuration element in Step 3 of the Forms Authentication Configuration and Advanced Topics
tutorial.Storing Roles and Role Associations
The Roles framework allows developers to define a set of roles and specify what users belong to what roles. This information is captured in the database through two tables:aspnet_Roles
and aspnet_UsersInRoles
. Each
record in the aspnet_Roles
table represents a role for a particular
application. Much like the aspnet_Users
table, the aspnet_Roles
table has three columns pertinent to our discussion:RoleId
RoleName
ApplicationId
RoleId
is the primary key (and of type uniqueidentifier
).
RoleName
is of type nvarchar(256)
. And ApplicationId
links the user account to a particular application in aspnet_Applications
.
There is a composite UNIQUE
constraint on the RoleName
and ApplicationId
columns, ensuring that in a given application each
role name is unique.The
aspnet_UsersInRoles
table serves as a mapping between users and
roles. There are only two columns - UserId
and RoleId
- and together they make up a composite primary key.Step 4: Specifying the Provider and Customizing Its Settings
All of the frameworks that support the provider model - such as the Membership and Roles frameworks - lack implementation details themselves and instead delegate that responsibility to a provider class. In the case of the Membership framework, theMembership
class defines the API for managing user accounts, but it
does not interact directly with any user store. Rather, the Membership
class's methods hand off the request to the configured provider - we will be using
the SqlMembershipProvider
. When we invoke one of the methods in the
Membership
class, how does the Membership framework know to delegate
the call to the SqlMembershipProvider
?The
Membership
class has a
Providers
property that contains a reference to all of the
registered provider classes available for use by the Membership framework. Each
registered provider has an associated name and type. The name offers a human-friendly
way to reference a particular provider in the Providers
collection,
while the type identifies the provider class. Moreover, each registered provider
may include configuration settings. Configuration settings for the Membership framework
include PasswordFormat
and requiresUniqueEmail
, among
many others. See Table 2 for a complete list of configuration settings used by the
SqlMembershipProvider
.The
Providers
property's contents are specified through the web application's
configuration settings. By default, all web applications have a provider named AspNetSqlMembershipProvider
of type SqlMembershipProvider
. This default Membership provider is
registered in machine.config
(located at %WINDIR%\Microsoft.Net\Framework\v2.0.50727\CONFIG
):
<membership>
<providers>
<add name="AspNetSqlMembershipProvider"
type="System.Web.Security.SqlMembershipProvider, System.Web, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a"
connectionStringName="LocalSqlServer"
enablePasswordRetrieval="false"
enablePasswordReset="true"
requiresQuestionAndAnswer="true"
applicationName="/"
requiresUniqueEmail="false"
passwordFormat="Hashed"
maxInvalidPasswordAttempts="5"
minRequiredPasswordLength="7"
minRequiredNonalphanumericCharacters="1"
passwordAttemptWindow="10"
passwordStrengthRegularExpression=""/>
</providers> </membership>
As the markup above shows, the
<membership>
element defines the configuration settings
for the Membership framework while the
<providers>
child element specifies the registered providers.
Providers may be added or removed using the
<add>
or
<remove>
elements; use the
<clear>
element to remove all currently registered
providers. As the markup above shows, machine.config
adds a provider
named AspNetSqlMembershipProvider
of type SqlMembershipProvider
.
In addition to the
name
and type
attributes, the <add>
element contains attributes that define the values for various configuring settings.
Table 2 lists the available SqlMembershipProvider
-specific configuration
settings, along with a description of each.Note: Any default values noted in Table 2 refer to the default values defined in the
SqlMembershipProvider
class. Note that not all of the configuration
settings in AspNetSqlMembershipProvider
correspond to the default values
of the SqlMembershipProvider
class. For example, if not specified in
a Membership provider, the requiresUniqueEmail
setting defaults to
true. However, the AspNetSqlMembershipProvider
overrides this default
value by explicitly specifying a value of false
.
Setting<_o3a_p />
|
Description<_o3a_p />
|
ApplicationName |
Recall that the Membership framework allows for a single user store to be partitioned
across multiple applications. This setting indicates the name of the application
partition used by the Membership provider. If this value is not explicitly specified,
it is set, at runtime, to the value of the application's virtual root path.
|
commandTimeout |
Specifies the SQL command timeout value (in seconds). The default value is 30.
|
connectionStringName |
The name of the connection string in the
<connectionStrings>
element to use to connect to the user store database. This value is required. |
description |
Provides a human-friendly description of the registered provider.
|
enablePasswordRetrieval |
Specifies whether users may retrieve their forgotten password. The default value
is
false . |
enablePasswordReset |
Indicates whether users are allowed to reset their password. Defaults to
true . |
maxInvalidPasswordAttempts |
The maximum number of unsuccessful login attempts that may occur for a given user
during the specified
passwordAttemptWindow
before the user is locked out. The default value is 5. |
minRequiredNonalphanumericCharacters |
The minimum number of non-alphanumeric characters that must appear in a user's password.
This value must be between 0 and 128; the default is 1.
|
minRequiredPasswordLength |
The minimum number of characters required in a password. This value must be between
0 and 128; the default is 7.
|
name |
The name of the registered provider. This value is required.
|
passwordAttemptWindow |
The number of minutes during which failed login attempts are tracked. If a user
supplies invalid login credentials
maxInvalidPasswordAttempts
times within this specified window, they are locked out. The default value is 10. |
PasswordFormat |
The password storage format:
Clear ,
Hashed , or Encrypted .
The default is
Hashed .
|
passwordStrengthRegularExpression |
If provided, this regular expression is used to evaluate the strength of the user's
selected password when creating a new account or when changing their password. The
default value is an empty string.
|
requiresQuestionAndAnswer |
Specifies whether a user must answer his security question when retrieving or resetting
his password. The default value is
true . |
requiresUniqueEmail |
Indicates whether all user accounts in a given application partition must have a
unique email address. The default value is
true . |
type |
Specifies the type of the provider. This value is required.
|
AspNetSqlMembershipProvider
, other Membership providers
may be registered on an application-by-application basis by adding similar markup
to the Web.config
file.Note: The Roles framework works in much the same way: there is a default registered role provider in
machine.config
and the registered providers
may be customized on an application-by-application basis in Web.config
.
We will examine the Roles framework and its configuration markup in detail in a
future tutorial.
Customizing the SqlMembershipProvider
Settings
The default SqlMembershipProvider
(AspNetSqlMembershipProvider
)
has its connectionStringName
attribute set to LocalSqlServer
.
Like the AspNetSqlMembershipProvider
provider, the connection string
name LocalSqlServer
is defined in machine.config
.
<connectionStrings>
<add name="LocalSqlServer"
connectionString="data source=.\SQLEXPRESS;Integrated Security=SSPI;AttachDBFilename=|DataDirectory|aspnetdb.mdf;User Instance=true"
providerName="System.Data.SqlClient"/> </connectionStrings>
As you can see, this connection string defines a SQL 2005 Express Edition database located at |DataDirectory|aspnetdb.mdf . The string |DataDirectory| is translated at runtime to point to the
~/App_Data/
directory, so the database path
|DataDirectory|aspnetdb.mdf translates to ~/App_Data
/aspnet.mdf
.
If we did not specify any Membership provider information in our application's
Web.config
file, the application uses the default registered Membership
provider, AspNetSqlMembershipProvider
. If the ~/App_Data/aspnet.mdf
database does not exist, the ASP.NET runtime will automatically create it and add
the application services schema. However, we don't want to use the aspnet.mdf
database; rather, we want to use the SecurityTutorials.mdf
database
we created in Step 2. This modification can be accomplished in one of two ways:- Specify a value for the
LocalSqlServer
connection string name inWeb.config
. By overwriting theLocalSqlServer
connection string name value inWeb.config
, we can use the default registered Membership provider (AspNetSqlMembershipProvider
) and have it correctly work with theSecurityTutorials.mdf
database. This approach is fine if you are content with the configuration settings specified byAspNetSqlMembershipProvider
. For more information on this technique, see Scott Guthrie's blog post, Configuring ASP.NET 2.0 Application Services to Use SQL Server 2000 or SQL Server 2005. - Add a new registered provider of type
SqlMembershipProvider
and configure itsconnectionStringName
setting to point to theSecurityTutorials.mdf
database. This approach is useful in scenarios where you want to customize other configuration properties in addition to the database connection string. In my own projects I always use this approach because of its flexibility and readability.
SecurityTutorials.mdf
database, we first need to add an appropriate connection string value in the <connectionStrings>
section in Web.config
. The following markup adds a new connection string
named SecurityTutorialsConnectionString
that references the SQL Server
2005 Express Edition SecurityTutorials.mdf
database in the App_Data
folder.
<configuration>
<connectionStrings>
<add name="SecurityTutorialsConnectionString"
connectionString="Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\SecurityTutorials.mdf;Integrated Security=True;User Instance=True"
providerName="System.Data.SqlClient"/>
</connectionStrings>
<system.web>
... Configuration markup removed for brevity ... </system.web>
</configuration>
Note: If you are using an alternate database file, update the connection string as needed. For more information on forming the correct connection string, refer to ConnectionStrings.com.
Next, add the following Membership configuration markup to the
Web.config
file. This markup registers a new provider named SecurityTutorialsSqlMembershipProvider
.
<configuration>
<connectionStrings>
<add name="SecurityTutorialsConnectionString"
connectionString="Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\SecurityTutorials.mdf;Integrated Security=True;User Instance=True"
providerName="System.Data.SqlClient"/>
</connectionStrings>
<system.web>
<membership defaultProvider="SecurityTutorialsSqlMembershipProvider">
<providers>
<!-- Add a customized SqlMembershipProvider -->
<add name="SecurityTutorialsSqlMembershipProvider"
type="System.Web.Security.SqlMembershipProvider"
connectionStringName="SecurityTutorialsConnectionString"
enablePasswordRetrieval="false"
enablePasswordReset="true"
requiresQuestionAndAnswer="true"
applicationName="SecurityTutorials"
requiresUniqueEmail="true"
passwordFormat="Hashed"
maxInvalidPasswordAttempts="5"
minRequiredPasswordLength="7"
minRequiredNonalphanumericCharacters="1"
passwordAttemptWindow="10"
passwordStrengthRegularExpression=""/>
</providers>
</membership>
... Configuration markup removed for brevity ...
</system.web>
</configuration>
In addition to registering the
SecurityTutorialsSqlMembershipProvider
provider, the above markup defines the SecurityTutorialsSqlMembershipProvider
as the default provider (via the defaultProvider
attribute in the
<membership>
element). Recall that the Membership framework can
have multiple registered providers. Since AspNetSqlMembershipProvider
is registered as the first provider in machine.config
, it serves as
the default provider unless we indicate otherwise.Currently, our application has two registered providers:
AspNetSqlMembershipProvider
and SecurityTutorialsSqlMembershipProvider
. However, before registering
the SecurityTutorialsSqlMembershipProvider
provider we could have cleared
out all previously registered providers by adding a
<clear />
element immediately before our <add>
element. This would clear out the AspNetSqlMembershipProvider
from
the list of registered providers, meaning that the SecurityTutorialsSqlMembershipProvider
would be the only registered Membership provider. If we used this approach, then
we would not need to mark the SecurityTutorialsSqlMembershipProvider
as the default provider, since it would be the only registered Membership provider.
For more information on using <clear />
, see
Using <clear />
When Adding providers.Note that the
SecurityTutorialsSqlMembershipProvider
's connectionStringName
setting references the just-added SecurityTutorialsConnectionString
connection string name, and that its applicationName
setting has been
set to a value of SecurityTutorials . Additionally, the requiresUniqueEmail
setting has been set to true
. All other configuration options are identical
to the values in AspNetSqlMembershipProvider
. Feel free to make any
configuration modifications here, if you wish. For example, you could tighten the
password strength by requiring two non-alphanumeric characters instead of one, or
by increasing the password length to eight characters instead of seven.Note: Recall that the Membership framework allows for a single user store to be partitioned across multiple applications. The Membership provider's
applicationName
setting indicates what application the provider uses when working with the user
store. It is important that you explicitly set a value for the applicationName
configuration setting because if the applicationName
is not explicitly
set, it is assigned to the web application's virtual root path at runtime. This
works fine as long as the application's virtual root path doesn't change, but if
you move the application to a different path, the applicationName
setting
will change too. When this happens, the Membership provider will start working with
a different application partition than was previously used. User accounts created
prior to the move will reside in a different application partition and those users
will no longer be able to log into the site. For a more in-depth discussion on this
matter, see
Always Set the applicationName
Property When Configuring ASP.NET 2.0
Membership and Other providers.Summary
At this point we have a database with the configured application services (SecurityTutorials.mdf
)
and have configured our web application so that the Membership framework uses the
SecurityTutorialsSqlMembershipProvider
provider we just registered.
This registered provider is of type SqlMembershipProvider
and has its
connectionStringName
set to the appropriate connection string (SecurityTutorialsConnectionString
)
and its applicationName
value explicitly set.We are now ready to use the Membership framework from our application. In the next tutorial we will examine how to create new user accounts. Following that we will explore authenticating users, performing user-based authorization, and storing additional user-related information in the database.
Happy Programming!
credits microsoft.com