servlet-security: Using Java EE Declarative Security to Control Servlet Access

Author: Sherif F. Makary, Pedro Igor, Stefan Guilhen
Level: Intermediate
Technologies: Servlet, Security
Summary: The servlet-security quickstart demonstrates the use of Java EE declarative security to control access to Servlets and Security in WildFly.
Target Product: WildFly
Source: https://github.com/wildfly/quickstart/

What is it?

The servlet-security quickstart demonstrates the use of Java EE declarative security to control access to Servlets and Security in WildFly Application Server.

When you deploy this example, two users are automatically created for you: user quickstartUser with password quickstartPwd1! and user guest with password guestPwd1!. This data is located in the src/main/resources/import.sql file.

This quickstart takes the following steps to implement Servlet security:

Web Application:
- Adds a security constraint to the Servlet using the @ServletSecurity and @HttpConstraint annotations.
- Adds a security domain reference to WEB-INF/jboss-web.xml.
- Adds a login-config that sets the auth-method to BASIC in the WEB-INF/web.xml.
Application Server (standalone.xml):
- Defines a security domain in the elytron subsystem that uses the JDBC security realm to obtain the security data used to authenticate and authorize users.
- Defines an http-authentication-factory in the elytron subsystem that uses the security domain created in step 1 for BASIC authentication.
- Adds an application-security-domain mapping in the undertow subsystem to map the Servlet security domain to the HTTP authentication factory defined in step 2.
Database Configuration:
- Adds an application user with access rights to the application.
```
User Name: quickstartUser
Password: quickstartPwd1!
Role: quickstarts
```
- Adds another user with no access rights to the application.
```
User Name: guest
Password: guestPwd1!
Role: notauthorized
```

Note: This quickstart uses the H2 database included with WildFly Application Server 11. It is a lightweight, relational example datasource that is used for examples only. It is not robust or scalable, is not supported, and should NOT be used in a production environment!

System Requirements

The application this project produces is designed to be run on WildFly Application Server 11 or later.

All you need to build this project is Java 8.0 (Java SDK 1.8) or later and Maven 3.3.1 or later. See Configure Maven for WildFly 11 to make sure you are configured correctly for testing the quickstarts.

Use of WILDFLY_HOME

In the following instructions, replace WILDFLY_HOME with the actual path to your WildFly installation. The installation path is described in detail here: Use of WILDFLY_HOME and JBOSS_HOME Variables.

Configure the Server

You can configure the server by running JBoss CLI commands. For your convenience, this quickstart batches the commands into a configure-server.cli script provided in the root directory of this quickstart.

Before you begin, back up your server configuration file
- If it is running, stop the WildFly server.
- Back up the file: WILDFLY_HOME/standalone/configuration/standalone.xml
- After you have completed testing this quickstart, you can replace this file to restore the server to its original configuration.

Start the WildFly server by typing the following:

For Linux:  WILDFLY_HOME/bin/standalone.sh
For Windows:  WILDFLY_HOME\bin\standalone.bat

Review the configure-server.cli file in the root of this quickstart directory. This script adds security domain and HTTP authentication factory to the elytron subsystem in the server configuration and also configures the undertow subsystem to use the configured HTTP authentication factory for the Web application.
Open a new command prompt, navigate to the root directory of this quickstart, and run the following command, replacing WILDFLY_HOME with the path to your server:
```
For Linux: WILDFLY_HOME/bin/jboss-cli.sh --connect --file=configure-server.cli
For Windows: WILDFLY_HOME\bin\jboss-cli.bat --connect --file=configure-server.cli
```
You should see the following result when you run the script:
```
The batch executed successfully
```
Stop the WildFly server.

Review the Modified Server Configuration

After stopping the server, open the WILDFLY_HOME/standalone/configuration/standalone.xml file and review the changes.

The following datasource was added to the datasources subsystem.

<datasource jndi-name="java:jboss/datasources/ServletSecurityDS" pool-name="ServletSecurityDS">
    <connection-url>jdbc:h2:mem:servlet-security;DB_CLOSE_ON_EXIT=FALSE</connection-url>
    <driver>h2</driver>
    <security>
        <user-name>sa</user-name>
        <password>sa</password>
    </security>
</datasource>

The following security-realm was added to the elytron subsystem.

<jdbc-realm name="servlet-security-jdbc-realm">
    <principal-query sql="SELECT PASSWORD FROM USERS WHERE USERNAME = ?" data-source="ServletSecurityDS">
        <clear-password-mapper password-index="1"/>
    </principal-query>
    <principal-query sql="SELECT R.NAME, 'Roles' FROM USERS_ROLES UR INNER JOIN ROLES R ON R.ID = UR.ROLE_ID INNER JOIN USERS U ON U.ID = UR.USER_ID WHERE U.USERNAME = ?" data-source="ServletSecurityDS">
        <attribute-mapping>
            <attribute to="roles" index="1"/>
        </attribute-mapping>
    </principal-query>
</jdbc-realm>

The security-realm is responsible for verifying the credentials for a given principal and for obtaining security attributes (like roles) that are associated with the authenticated identity.

The following role-decoder was added to the elytron subsystem.
```
<simple-role-decoder name="from-roles-attribute" attribute="roles"/>
```
The jdbc-realm in this quickstart stores the roles associated with a principal in an attribute named roles. Other realms might use different attributes for roles (such as group). The purpose of a role-decoder is to instruct the security domain how roles are to be retrieved from an authorized identity.

The following security-domain was added to the elytron subsystem.

<security-domain name="servlet-security-quickstart-sd" default-realm="servlet-security-jdbc-realm" permission-mapper="default-permission-mapper">
    <realm name="servlet-security-jdbc-realm" role-decoder="from-roles-attribute"/>
</security-domain>

The following http-authentication-factory was added to the elytron subsystem.

<http-authentication-factory name="servlet-security-quickstart-http-auth" http-server-mechanism-factory="global" security-domain="servlet-security-quickstart-sd">
    <mechanism-configuration>
        <mechanism mechanism-name="BASIC">
            <mechanism-realm realm-name="RealmUsersRoles"/>
        </mechanism>
    </mechanism-configuration>
</http-authentication-factory>

It basically defines an HTTP authentication factory for the BASIC mechanism that relies on the servlet-security-quickstart-sd security domain to authenticate and authorize access to Web applications.

The following application-security-domain was added to the undertow subsystem.

<application-security-domains>
    <application-security-domain name="servlet-security-quickstart" http-authentication-factory="servlet-security-quickstart-http-auth"/>
</application-security-domains>

This configuration tells Undertow that applications with the servlet-security-quickstart security domain, as defined in the jboss-web.xml or by using the @SecurityDomain annotation in the Servlet class, should use the http-authentication-factory named servlet-security-quickstart-http-auth. If no application-security-domain is defined for a particular security domain, Undertow assumes the legacy JAAS based security domains should be used for authentication/authorization and, in this case, the security domain defined in the Web application must match a security domain in the legacy security subsystem. The presence of an application-security-domain configuration is what enables Elytron authentication for a Web application.

Start the Server

Open a command prompt and navigate to the root of the WildFly directory.

The following shows the command line to start the server:

For Linux:   WILDFLY_HOME/bin/standalone.sh
For Windows: WILDFLY_HOME\bin\standalone.bat

Build and Deploy the Quickstart

Make sure you have started the WildFly server as described above.
Open a command prompt and navigate to the root directory of this quickstart.
Type this command to build and deploy the archive:
```
mvn clean install wildfly:deploy
```
This will deploy target/servlet-security.war to the running instance of the server.

Access the Application

The application will be running at the following URL http://localhost:8080/servlet-security/.

When you access the application, you should get a browser login challenge.

Log in using the username quickstartUser and password quickstartPwd1!. The browser will display the following security info:

Successfully called Secured Servlet

Principal : quickstartUser
Remote User : quickstartUser
Authentication Type : BASIC

Now close the browser. Open a new browser and log in with username guest and password guestPwd1!. The browser will display the following error:

Forbidden

Server Log: Expected Warnings and Errors

Note: You will see the following warning in the server log. You can ignore it.

HHH000431: Unable to determine H2 database version, certain features may not work

Undeploy the Archive

Make sure you have started the WildFly server as described above.
Open a command prompt and navigate to the root directory of this quickstart.
When you are finished testing, type this command to undeploy the archive:
```
mvn wildfly:undeploy
```

Restore the Server Configuration

You can restore the original server configuration by running the restore-configuration.cli script provided in the root directory of this quickstart or by manually restoring the back-up copy the configuration file.

Restore the Server Configuration by Running the JBoss CLI Script

Start the WildFly server by typing the following:

For Linux:  WILDFLY_HOME/bin/standalone.sh
For Windows:  WILDFLY_HOME\bin\standalone.bat

Open a new command prompt, navigate to the root directory of this quickstart, and run the following command, replacing WILDFLY_HOME with the path to your server:

For Linux: WILDFLY_HOME/bin/jboss-cli.sh --connect --file=restore-configuration.cli
For Windows: WILDFLY_HOME\bin\jboss-cli.bat --connect --file=restore-configuration.cli

This script removes the application-security-domain configuration from the undertow subsystem, the http-authentication-factory, security-domain, security-realm and role-decoder configuration from the elytron subsystem and it also removes the datasource used for this quickstart. You should see the following result when you run the script:

    The batch executed successfully
    process-state: reload-required

Restore the Server Configuration Manually

If it is running, stop the WildFly server.
Replace the WILDFLY_HOME/standalone/configuration/standalone.xml file with the back-up copy of the file.

Run the Quickstart in Red Hat JBoss Developer Studio or Eclipse

You can also start the server and deploy the quickstarts or run the Arquillian tests from Eclipse using JBoss tools. For general information about how to import a quickstart, add a WildFly server, and build and deploy a quickstart, see Use JBoss Developer Studio or Eclipse to Run the Quickstarts.

Be sure to configure the server by running the JBoss CLI commands as described above under Configure the WildFly Server. Stop the server at the end of that step.
Be sure to Restore the Server Configuration when you have completed testing this quickstart.

Debug the Application

If you want to debug the source code of any library in the project, run the following command to pull the source into your local repository. The IDE should then detect it.

  mvn dependency:sources