Forms based nginx login and pluggable shiro auth in karaf

My usecase was this: I had a set of small OSGi web whiteboard web applications running in apache karaf fronted by nginx and I wanted to have the same login and set of users across all web application, and I wanted to have the same forms based for nginx as well. A sort of “poor man’s single signon”.

This project was my solution.

This project contains a set of apache karaf features that fills two purposes

1. Providing a forms based login mechanism for nginx (Note: the webapp provides only authentication. No authorization of individual URLs. All authenticated users get in)
2. Providing a “poor man’s single sign-on” for web applications running in the same apache karaf instance

Status of the project

SonarCloud

Installing on karaf

Note: The instructions here don’t describe a production enviroment, but they describe setting up something that will let the service be startet.

The webapp needs PostgreSQL running, with a database named “ukelonn” containing the table users, and a no-password authentication scheme.

Instructions:

1. In bash, clone and build the authservice app:

   mkdir -p ~/git/
   cd ~/git/
   git clone https://github.com/steinarb/authservice.git
   cd ~/git/authservice/
   mvn clean install
       

2. Follow the quick start guide to downloading, unpacking and starting apache karaf
3. In the karaf shell, install the authservice feature repository

   feature:repo-add mvn:no.priv.bang.authservice/authservice/LATEST/xml/features
       

4. In the karaf shell, install the feature that installs the authorization service that is used by nginx (this feature installs a set of test users, roles and features)

   feature:install authservice-with-testdb-dbrealm-and-session
       

5. Open a browser on the URL http://localhost:8181/authservice and do a login with a valid username/password combination (e.g. “admin/admin”)
6. Open a browser on the URL http://localhost:8181/authservice/check and verify that it doesn’t return a 401 HTTP code
7. Optionally install the user administration UI (not needed for using this service with nginx, but needed for administrating the access)

   feature:install user-admin-with-testdb
       

8. Open a browser on the URL http://localhost:8181/authservice/useradmin and test adding/modifying users, roles and permissions

Forms based login for nginx

The webapp installed by the above installation instructions offers two URLs for use by the NGINX auth_request module:

• /auth which will just check the login state of Apache Shiro, returning the status code 401 for failure and 200 for success
• /login which contains a login form and will authenticate against Apache Shiro

The webapp is implemented as two servlets exposed as OSGi services, that will be picked up by the pax web whiteboard extender.

Installing and configuring nginx

Instructions:

1. Install nginx with the auth module. On debian this is done with the command

   apt-get update
   apt-get install nginx-extras
       

2. Add the following to the /etc/nginx/sites-available/default (adapt this to the actual server/site in use):

   server {
           listen 80 default_server;
           listen [::]:80 default_server;
   
           root /var/www/html;
   
           # Add index.php to the list if you are using PHP
           index index.html index.htm index.nginx-debian.html;
   
           server_name _;
   
           location /authservice {
                   auth_request off; # Necessary for REST API POST to work, shiro will handle authorization here
                   proxy_pass http://localhost:8181/authservice;
                   proxy_cookie_path ~^/authservice.*$ /;
                   proxy_set_header Host $host;
           }
   
           # Avoid browser attempt at fetching favicon.ico triggering a login and redirecting
           # a 404 Not Found when there is no favicon.ico on the site (which is perferctly OK
           # for both the site and the browser)
           location /favicon.ico {
                   auth_request off;
           }
   
            location / {
                   # First attempt to serve request as file, then
                   # as directory, then fall back to displaying a 404.
                   try_files $uri $uri/ =404;
           }
   
           # Auth configuration
           auth_request /authservice/check;
           error_page 401 = @error401;
   
           # If the user is not logged in, redirect to authservice login URL, with redirect information
           location @error401 {
                   add_header X-Original-URI "$scheme://$http_host$request_uri";
                   add_header Set-Cookie "NSREDIRECT=$scheme://$http_host$request_uri";
                   return 302 /authservice/login?originalUri=$scheme://$http_host$request_uri;
            }
   }
       

Installing and configuring postgresql

Note: only command examples for debian/ubuntu/etc. are shown, but the overall steps should work on a lot of platforms

1. Install PostgreSQL, as root do the following command:

   apt-get install postgresql
       

2. Add a PostgreSQL user named “karaf”, as root do the following command

   PGPASSWORD=karaf sudo -u postgres createuser karaf
       

   Note: Replace the password in the PGPASSWORD environment variable with something other than the example and use that password in the karaf configuration

3. Create an empty PostgreSQL database named “authservice” owned by user “karaf”

   sudo -u postgres createdb -O karaf authservice
       

Installing and configuring apache karaf

Instructions:

1. Install apache karaf as a service, either using the karaf installation scripts or by using apt-get and the unofficial karaf deb package
2. SSH in to the karaf console:

   ssh -p 8101 karaf@localhost
       

   The default password is “karaf” (without the quotes). It might be a good idea to change this. See the karaf documentation for how to change the password

3. In the karaf console, do the following:
   1. Add connection configuration for the postgresql database:

      config:edit org.ops4j.datasource-authservice-production
      config:property-set osgi.jdbc.driver.name "PostgreSQL JDBC Driver"
      config:property-set dataSourceName "jdbc/authservice"
      config:property-set ops4j.preHook "authservicedb"
      config:property-set org.apache.karaf.features.configKey "org.ops4j.datasource-authservice-production"
      config:property-set url "jdbc:postgresql:///authservice"
      config:property-set user "karaf"
      config:property-set password "karaf"
      config:update
              

      Note: use the actual password given in the PGPASSWORD environment variable when creating the karaf user

   2. Install authservice from maven central:

      feature:repo-add mvn:no.priv.bang.authservice/authservice/LATEST/xml/features
      feature:install user-admin-with-productiondb
              

4. Open a the nginx authservice URL in a web browser, e.g. https://myserver.com/authservice/ and:
   1. Log in as user “admin” with password “admin” (without the quotes)
   2. Click on the “User administration UI” link
   3. In the administration UI:
      1. Click on “Administrate users”
      2. Change the password of user “admin”
      3. Add users that are to be able to log in to nginx Note: The nginx config provides only authentication for nginx, no authorization based on the combination of path and role or permission. Therefore there is no need to add roles to users that only needs to log in Users that need to administrate other users, should get the useradmin role
   4. Add some links to the selfservice URLs from your website’s top page (or whereever is convenient):
      1. Change password: https://myserver.com/authservice/password/
      2. Modify real namd and email: https://myserver.com/authservice/user

Integrating with a Declarative Services (DS) web whiteboard application in karaf

Note: only command examples for debian/ubuntu/etc. are shown, but the overall steps should work on a lot of platforms

Do the following steps:

1. Install PostgreSQL, as root do the following command:

   apt-get install postgresql
       

2. Add a PostgreSQL user named “karaf”, as root do the following command

   PGPASSWORD=karaf sudo -u postgres createuser karaf
       

   Note: Replace the password in the PGPASSWORD environment variable with something other than the example and use that password in the karaf configuration

3. Create an empty PostgreSQL database named “authservice” owned by user “karaf”

   sudo -u postgres createdb -O karaf authservice
       

4. SSH into the karaf console and add connection configuration for the postgresql database with the following commands:

   config:edit org.ops4j.datasource-authservice-production
   config:property-set osgi.jdbc.driver.name "PostgreSQL JDBC Driver"
   config:property-set dataSourceName "jdbc/authservice"
   config:property-set ops4j.preHook "authservicedb"
   config:property-set url "jdbc:postgresql:///authservice"
   config:property-set user "karaf"
   config:property-set password "karaf"
   config:update
       

   Note: use the actual password given in the PGPASSWORD environment variable when creating the karaf user

5. Create a new DS component maven project, containing
   1. A src/main/feature/feature.xml template file, referencing the authservice feature repository and the authservice feature, e.g.:

      <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
      <features xmlns="http://karaf.apache.org/xmlns/features/v1.5.0" name="authservice.bundle">
          <repository>mvn:no.priv.bang.authservice/authservice/1.11.15/xml/features</repository>
          <feature name="${karaf-feature-name}">
              <feature>user-admin-with-productiondb</feature>
          </feature>
      </features>
              

   2. Add a shiro compile time dependency to the project’s maven dependencies:

      <dependency>
          <groupId>org.apache.shiro</groupId>
          <artifactId>shiro-core</artifactId>
          <version>1.3.2</version>
          <scope>provided</scope>
      </dependency>
              

   3. A DS component exposing a ServletContextHelper service to the web whiteboard, e.g.:

      @Component(
          property= {
              HttpWhiteboardConstants.HTTP_WHITEBOARD_CONTEXT_NAME+"=ukelonn",
              HttpWhiteboardConstants.HTTP_WHITEBOARD_CONTEXT_PATH+"=/ukelonn"},
          service=ServletContextHelper.class,
          immediate=true
      )
      public class UkelonnServletContextHelper extends ServletContextHelper { }
              

   4. A DS component exposing a Filter service to the web whiteboard, extending the AbstractShiroFilter, requiring shiro Realm and SessionDAO OSGi service injections, and configured using code (the shiro.ini mechanism doesn’t work well in OSGi), eg.:

      @Component(
          property= {
              HttpWhiteboardConstants.HTTP_WHITEBOARD_FILTER_PATTERN+"=/*",
              HttpWhiteboardConstants.HTTP_WHITEBOARD_CONTEXT_SELECT + "=(" + HttpWhiteboardConstants.HTTP_WHITEBOARD_CONTEXT_NAME +"=ukelonn)",
              "servletNames=ukelonn"},
          service=Filter.class,
          immediate=true
      )
      public class UkelonnShiroFilter extends AbstractShiroFilter { // NOSONAR
      
          private Realm realm;
          private SessionDAO session;
          private static final Ini INI_FILE = new Ini();
          static {
              // Can't use the Ini.fromResourcePath(String) method because it can't find "shiro.ini" on the classpath in an OSGi context
              INI_FILE.load(UkelonnShiroFilter.class.getClassLoader().getResourceAsStream("shiro.ini"));
          }
      
          @Reference
          public void setRealm(Realm realm) {
              this.realm = realm;
          }
      
          @Reference
          public void setSession(SessionDAO session) {
              this.session = session;
          }
      
          @Activate
          public void activate() {
              WebIniSecurityManagerFactory securityManagerFactory = new WebIniSecurityManagerFactory(INI_FILE);
              DefaultWebSecurityManager securityManager = (DefaultWebSecurityManager) securityManagerFactory.createInstance();
              DefaultWebSessionManager sessionmanager = new DefaultWebSessionManager();
              sessionmanager.setSessionDAO(session);
              securityManager.setSessionManager(sessionmanager);
              setSecurityManager(securityManager);
              securityManager.setRealm(realm);
      
              IniFilterChainResolverFactory filterChainResolverFactory = new IniFilterChainResolverFactory(INI_FILE, securityManagerFactory.getBeans());
              FilterChainResolver resolver = filterChainResolverFactory.createInstance();
              setFilterChainResolver(resolver);
          }
      }
              

   5. A shiro.ini resource containing a [urls] section providing access to various path, e.g:

      [main]
      authc.loginUrl = /login
      
      [users]
      
      [urls]
      / = authc
      /user* = user
      /admin/** = roles[administrator]
      /api/login = anon
      /api/registerpayment = roles[administrator]
      /api/job/update = roles[administrator]
      /api/admin/** = roles[administrator]
      /api/** = authc
      /performedjobs = authc
      /performedpayments = authc
              

   6. Something listening to the /login path inside the context provided by the WebContextHelper (i.e. /ukelonn/login in this example) and handling login. “Something” could be a servlet or a JAX-RS resource. An example of a JAX-RS resource to handle login, is this resource, which when receiving a GET returns an HTML page with a login form, and on receiving a POST from the form, performs the login:

      @Path("")
      public class LoginResource {
      
          @GET
          @Path("/login")
          @Produces(MediaType.TEXT_HTML)
          public InputStream getLogin() {
              return getClass().getClassLoader().getResourceAsStream("web/login.html");
          }
      
          @POST
          @Path("/login")
          @Consumes(MediaType.APPLICATION_FORM_URLENCODED)
          @Produces("text/html")
          public Response postLogin(@FormParam("username") String username, @FormParam("password") String password) {
              Subject subject = SecurityUtils.getSubject();
      
              UsernamePasswordToken token = new UsernamePasswordToken(username, password.toCharArray(), true);
              try {
                  subject.login(token);
      
                  return Response.status(Response.Status.FOUND).entity("Login successful!").build();
              } catch(UnknownAccountException e) {
                  return Response.status(Response.Status.UNAUTHORIZED).entity("Unknown account")).build();
              } catch (IncorrectCredentialsException  e) {
                  return Response.status(Response.Status.UNAUTHORIZED).entity("Wrong password")).build();
              } catch (LockedAccountException  e) {
                  return Response.status(Response.Status.UNAUTHORIZED).entity("Account is locked")).build();
              } catch (AuthenticationException e) {
                  return Response.status(Response.Status.UNAUTHORIZED).entity("Unable to log in")).build();
              } catch (Exception e) {
                  throw new InternalServerErrorException();
              } finally {
                  token.clear();
              }
          }
      }
              

      Note! if the user logs in via the login form on the authservice path on the same karaf server, the user will be logged into your application as well.

6. A barebones DS component plugging into authservice, and that can be adapted to your project, can be found at authservice-sampleclient

Various ways of integrating with other webapps in karaf

There are several ways for a webapp to interact with authservice:

1. Install authservice separately and add OSGi service injections for shiro Realm and Session (all user administration done in the authservice webapplication)
2. Add the features for the liquibase database setup and the shiro Realm and Session and provide the necessary tables from a different web application’s database
3. Add the features for the authservice UserManagementService implementation, as well as the features for Realm and Session and and implement a user management GUI and webservice on top of the UserManagementService

…or various permutations of the above. With ukelonn I plan to add the authservice tables to the ukelonn database, and then let the ukelonn database provide the database for authservice itself. I have made a first step in the direction of authservice integration by basing ukelonn’s user management on the UserManagementService OSGi service, so that it later can be replaced by the authservice implementation of the service.

Integrating with other databases than PostgreSQL and derby

Short story: it should be possible. It should possible to use blank JDBC database that can be connected to with a combination of a JDBC url and username and password.

Currently authservice operates with two databases: an in-memory derby with mock data used for tests and development, and a PostgreSQL database used for production deployments.

Authservice uses XML syntax liquibase to set up the schema, straightforward SQL to insert initial data/mock data, and straightforward SQL to updated and query the authservice database, so replacing both derby and PostgreSQL, with other JDBC databases supported by liquibase (which is basically all of them), should be possible.

Please note however, that none of the config below has been tested.

Replacing the test database (by default derby):

Possible approach:

1. In the karaf console, configure connection information to the alternative database (H2 in-memory database in the example):

   config:edit org.ops4j.datasource-authservice-test
   config:property-set osgi.jdbc.driver.name "H2"
   config:property-set dataSourceName "jdbc/authservice"
   config:property-set ops4j.preHook "authservicedb"
   config:property-set url "jdbc:h2:mem:authservice"
   config:update
       

2. In the karaf console, install the H2 karaf feature (there is nothing in the authservice karaf features that loads this):

   feature:install pax-jdbc-h2
       

3. Load the authservice feature repository:

   feature:repo-add mvn:no.priv.bang.authservice/authservice/LATEST/xml/features
       

4. In the karaf console, load the test database authservice feature

   feature:install authservice-with-testdb-dbrealm-and-session
       

5. Alternatively, load the test database user-admin feature (this is a superset of the authservice feature that adds a GUI for user management):

   feature:install user-admin-with-testdb
       

Replacing the production database (by default PostgreSQL):

Possible approach:

1. In the karaf console, configure connection information to the alternative database (MySQL in the example):

   config:edit org.ops4j.datasource-authservice-production
   config:property-set osgi.jdbc.driver.name "mysql"
   config:property-set dataSourceName "jdbc/authservice"
   config:property-set ops4j.preHook "authservicedb"
   config:property-set url "jdbc:mysql://localhost/authservice"
   config:property-set user "karaf"
   config:property-set password "karaf"
   config:update
       

2. In the karaf console, install the H2 karaf feature (there is nothing in the authservice karaf features that loads this):

   feature:install pax-jdbc-mysql
       

3. Load the authservice feature repository:

   feature:repo-add mvn:no.priv.bang.authservice/authservice/LATEST/xml/features
       

4. In the karaf console, load the test database authservice feature

   feature:install authservice-with-productiondb-dbrealm-and-session
       

5. Alternatively, load the test database user-admin feature (this is a superset of the authservice feature that adds a GUI for user management):

   feature:install user-admin-with-productiondb
       

Release history

License

This software is licensed under Apache Public License v 2.0.

See the LICENSE file for the full details.