GeoMesa Authorizations

This tutorial demonstrates the ways you can apply data-level security to GeoMesa. It is a more advanced tutorial; you should already be familiar with the basics of GeoMesa and GeoServer. This tutorial targets Accumulo - GeoMesa also supports HBase visibilities through the same mechanisms, but the HBase configuration required is not covered here. See HBase Visibilities for more information on HBase.

In this tutorial, you will learn how to:

  1. Set visibilities on your data during ingestion into GeoMesa
  2. Apply authorizations to your queries through GeoMesa
  3. Implement user authorizations through the GeoMesa GeoServer plugin, using PKI certs to authenticate with GeoServer and LDAP to store authorizations

Background

Visibilities and Authorizations

One of the most powerful features of Accumulo is the implementation of cell-level security, using visibilities and authorizations. Data that is protected by visibilities can only be seen by users that have the corresponding authorizations. This allows for the fine-grained protection of data, based on arbitrary labels.

Note

Authorizations are distinct from table-level permissions, and operate at a much finer grain.

Public Key Infrastructure (PKI)

Public key infrastructure can be used to securely authenticate end users. In PKI, a certificate authority (CA) will issue digital certificates that verify that a particular public key belongs to a particular individual. Other users can then trust that certificate because it has been digitally signed by the CA.

In this tutorial, the keys used are not provided by trusted CAs. As such, it is necessary to import the CA’s certificate into the Java keystore, which allows Java (and by extension Tomcat) to trust any keys verified by the CA.

PKI solves the issue of authentication (who a user is) but not authorization (what a user can do). For this tutorial, authorization is provided by an LDAP server.

Prerequisites

Before you begin, you must have the following:

  • Java JDK 1.8
  • Apache Maven 3.5.2 or later
  • a GitHub client
  • an Accumulo 1.7.x, 1.8.x, 1.9.x or 2.0.x instance
  • an Accumulo user that has both create-table and write permissions
  • the GeoMesa distributed runtime installed for your instance

If you are not familiar with Accumulo authorizations, you should review the relevant Accumulo documentation, with more examples here.

About this Tutorial

This tutorial operates by inserting and then querying several thousand features. The features are inserted with visibility labels, and then queried with two different users to show how authorizations work.

Visibilities in GeoMesa

GeoMesa supports setting the visibility for each feature that is written. This can be set through user data in a simple feature:

SimpleFeature sf = ...;
// set user data directly
sf.getUserData().put(SecurityUtils.FEATURE_VISIBILITY, "user&admin");
// alternatively, use static utility methods
org.locationtech.geomesa.security.SecurityUtils.setFeatureVisibilities(sf, "user", "admin");

For more information on feature-level visibilities, see Feature Level Visibility and Security.

Authorizations in GeoMesa

When performing a query, GeoMesa delegates the retrieval of authorizations to service providers that implement the following interface:

package org.locationtech.geomesa.security;

public interface AuthorizationsProvider {

    /**
     * Gets the authorizations for the current context. This may change over time
     * (e.g. in a multi-user environment), so the result should not be cached.
     *
     * @return
     */
    List<String> getAuthorizations();

    /**
     * Configures this instance with parameters passed into the DataStoreFinder
     *
     * @param params
     */
    void configure(Map<String, Serializable> params);
}

When a GeoMesa DataStore is instantiated, it will scan for available service providers. Third-party implementations can be enabled by placing them on the classpath and including a special service descriptor file. See the Oracle Javadoc for details on implementing a service provider.

The GeoMesa DataStore will call configure() on the AuthorizationsProvider implementation, passing in the parameter map from the call to DataStoreFinder.getDataStore(Map params). This allows the AuthorizationsProvider to configure itself based on the environment.

To ensure that the correct AuthorizationsProvider is used, GeoMesa will throw an exception if multiple third-party service providers are found on the classpath. In this scenario, the particular service provider class to use can be specified by the following system property:

AuthorizationsProvider.AUTH_PROVIDER_SYS_PROPERTY = "geomesa.auth.provider.impl";

For simple scenarios, the set of authorizations to apply to all queries can be specified when creating the GeoMesa DataStore by using the geomesa.security.auths configuration parameter. This will use the DefaultAuthorizationsProvider implementation provided by GeoMesa.

// create a map containing initialization data for the GeoMesa data store
Map<String, String> configuration = new HashMap<>();
configuration.put("geomesa.security.auths", "user,admin");
DataStore dataStore = DataStoreFinder.getDataStore(configuration);

If there are no AuthorizationsProviders found on the classpath, and the geomesa.security.auths parameter is not set, GeoMesa will default to using the authorizations associated with the underlying Accumulo connection (i.e. the accumulo.user configuration value).

Warning

This is not a recommended approach for a production system.

In addition, please note that the authorizations used in any scenario cannot exceed the authorizations of the underlying Accumulo connection.

Create Visibilities in Accumulo

This tutorial requires that you specify a visibility string and the associated authorizations string. The visibilities can be anything valid for your Accumulo instance. For the rest of this exercise, we are going to assume the visibility string is user. You can see the visibilities that are currently enabled for your user through the Accumulo shell:

$ accumulo shell -u <username> -p <password>

Once in the shell:

> getauths
user,admin

If your user does not already have authorizations, you can add them through the Accumulo shell with the addauths command:

> getauths
user
> addauths -s admin -u myuser
> getauths
user,admin

Note

A user cannot set authorizations unless the user has the System.ALTER_USER permission.

After running the tutorial code, you should see a visibility label in square brackets when you scan the index tables through the Accumulo shell:

> scan -t mytable_id
\x0100700230-fdfe-422e-b4d1-8072db6f3dda SFT: [user]    \x02\x00\x00\x01b00700230...

Download and Build the Tutorial

Pick a reasonable directory on your machine, and run:

$ git clone https://github.com/geomesa/geomesa-tutorials.git
$ cd geomesa-tutorials

Warning

Make sure that you download or checkout the version of the tutorials project that corresponds to your GeoMesa version. See About Tutorial Versions for more details.

To ensure that the quick start works with your environment, modify the pom.xml to set the appropriate versions for Accumulo, Hadoop, etc.

For ease of use, the project builds a bundled artifact that contains all the required dependencies in a single JAR. To build, run:

$ mvn clean install -pl geomesa-tutorials-accumulo/geomesa-tutorials-accumulo-authorizations -am

Run the Tutorial

On the command line, run:

$ java -cp geomesa-tutorials-accumulo/geomesa-tutorials-accumulo-authorizations/target/geomesa-tutorials-accumulo-authorizations-${geomesa.version}.jar \
    org.geomesa.example.accumulo.auths.AuthorizationsTutorial \
    --accumulo.instance.id <instance>                         \
    --accumulo.zookeepers <zookeepers>                        \
    --accumulo.user <user>                                    \
    --accumulo.password <password>                            \
    --accumulo.catalog <table>                                \
    --geomesa.security.auths <authorizations>                 \
    --visibilities <visibilities>

where you provide the following arguments:

  • <instance> the name of your Accumulo instance
  • <zookeepers> your Zookeeper nodes, separated by commas
  • <user> the name of an Accumulo user that has permissions to create, read and write tables
  • <password> the password for the previously-mentioned Accumulo user
  • <table> the name of the destination table that will accept these test records. This table should either not exist or should be empty
  • <visibilities> the visibilities label to apply to the data, e.g. user
  • <authorizations> the authorizations associated with the visibilities you selected, e.g. user. Make sure that your Accumulo user has the authorization you use

Warning

If you have set up the GeoMesa Accumulo distributed runtime to be isolated within a namespace (see Namespace Install) the value of <table> should include the namespace (e.g. myNamespace.geomesa).

Optionally, you can also specify that the tutorial should delete its data upon completion. Use the --cleanup flag when you run to enable this behavior.

Once run, you should see the following output:

Loading datastore

Loading datastore

Creating schema: GLOBALEVENTID:String,Actor1Name:String,Actor1CountryCode:String,Actor2Name:String,Actor2CountryCode:String,EventCode:String,NumMentions:Integer,NumSources:Integer,NumArticles:Integer,ActionGeo_Type:Integer,ActionGeo_FullName:String,ActionGeo_CountryCode:String,dtg:Date,geom:Point

Generating test data

Writing test data
Wrote 2356 features

Executing query with AUTHORIZED data store: auths are 'user'
Running query dtg BETWEEN 2017-12-31T00:00:00+00:00 AND 2018-01-02T00:00:00+00:00 AND BBOX(geom, -83.0,33.0,-80.0,35.0)
01 719024887=719024887|DEPUTY||||010|4|1|4|3|Abbeville County, South Carolina, United States|US|2017-12-31T00:00:00.000Z|POINT (-82.4665 34.2334)
02 719024893=719024893|UNITED STATES|USA|DEPUTY||010|6|1|6|3|Abbeville County, South Carolina, United States|US|2017-12-31T00:00:00.000Z|POINT (-82.4665 34.2334)
03 719024895=719024895|UNITED STATES|USA|EMPLOYEE||010|2|1|2|3|Ninety Six, South Carolina, United States|US|2017-12-31T00:00:00.000Z|POINT (-82.024 34.1751)
04 719025110=719025110|||UNITED STATES|USA|051|6|1|6|3|Edgefield, South Carolina, United States|US|2018-01-01T00:00:00.000Z|POINT (-81.9296 33.7896)
05 719025605=719025605|SCHOOL||ADMINISTRATION||043|16|1|16|3|Greenwood County, South Carolina, United States|US|2018-01-01T00:00:00.000Z|POINT (-82.1165 34.1668)
06 719025410=719025410|POLICE||||193|1|1|1|3|Ninety Six National Historic Site, South Carolina, United States|US|2018-01-01T00:00:00.000Z|POINT (-82.0193 34.146)
07 719027188=719027188|UNITED STATES|USA|UNITED STATES|USA|193|1|1|1|3|Ware Shoals, South Carolina, United States|US|2018-01-01T00:00:00.000Z|POINT (-82.2468 34.3985)
08 719024941=719024941|||DEPUTIES||090|8|1|8|3|Edgewood, South Carolina, United States|US|2018-01-01T00:00:00.000Z|POINT (-80.6137 34.2874)
09 719024950=719024950|||DEPUTIES||190|8|1|8|3|Edgewood, South Carolina, United States|US|2018-01-01T00:00:00.000Z|POINT (-80.6137 34.2874)
10 719024894=719024894|UNITED STATES|USA|DEPUTY||010|2|1|2|3|Abbeville County, South Carolina, United States|US|2017-12-31T00:00:00.000Z|POINT (-82.4665 34.2334)

Returned 39 total features

Executing query with UNAUTHORIZED data store: auths are ''
Running query dtg BETWEEN 2017-12-31T00:00:00+00:00 AND 2018-01-02T00:00:00+00:00 AND BBOX(geom, -83.0,33.0,-80.0,35.0)

Returned 0 total features

Done

The first query should return 1 or more results. The second query should return 0 results, since they are hidden by visibilities.

Looking at the Code

The source code is meant to be accessible for this tutorial. The main logic is contained in org.geomesa.example.accumulo.auths.AuthorizationsTutorial in the geomesa-tutorials-accumulo/geomesa-tutorials-accumulo-authorizations module. Some relevant methods are:

  • createDataStore uses a system property to control the visibility provider used by each data store
  • queryFeatures run the same query with each data store
// get an instance of the data store that uses our authorizations provider,
// that always returns empty auths
System.setProperty(AuthorizationsProvider.AUTH_PROVIDER_SYS_PROPERTY,
                   EmptyAuthorizationsProvider.class.getName());
unauthorizedDatastore = super.createDataStore(params);

// get an instance of the data store that uses the default authorizations provider,
// which will use whatever auths the connector has available
System.setProperty(AuthorizationsProvider.AUTH_PROVIDER_SYS_PROPERTY,
                   DefaultAuthorizationsProvider.class.getName());
return super.createDataStore(params);

This code snippet shows how you can specify the AuthorizationProvider to use with a system property. The DefaultAuthorizationsProvider class is provided by GeoMesa, and used when no other implementations are found.

The EmptyAuthorizationsProvider class is included in the tutorial. The EmptyAuthorizationsProvider will always return an empty Authorizations object, which means that any data stored with visibilities will not be returned.

There is a more useful implementation of AuthorizationsProvider that will be explored in more detail in the next section, the LdapAuthorizationsProvider.

Applying Authorizations and Visibilities to GeoServer Using PKIS and LDAP

This section will show you how to configure GeoServer to authenticate users with PKIs, use LDAP to store authorizations, and apply authorizations on a per-user/per-query basis.

Basic user authentication will take place via user certificates. Each user will have their own public/private key pair that uniquely identifies them.

User authorizations will come from LDAP. Once a user’s identity has been verified via PKI, we will look up the user’s details in LDAP.

Once we have a user’s authentication and authorizations, we will apply them to the GeoMesa query using a custom AuthorizationsProvider implementation.

Run GeoServer in Tomcat

Note

If you are already running GeoServer in Tomcat, you can skip this step.

GeoServer ships by default with an embedded Jetty servlet. In order to use PKI login, we need to install it in Tomcat instead.

  1. Download and install Tomcat 7.

  2. Create an environment variable pointing to your tomcat installation (you may want to add this to your bash init scripts):

    $ export CATALINA_HOME=/path/to/tomcat
    
  3. If you want to reuse your existing GeoServer configuration, create an environment variable pointing to your GeoServer data directory (you may want to add this to your shell initialization scripts):

    $ export GEOSERVER_DATA_DIR=/path/to/geoserver/data_dir
    
  4. Copy the GeoServer webapp from the GeoServer distribution into the tomcat servlet:

    $ cp -r /path/to/geoserver/webapps/geoserver/ $CATALINA_HOME/webapps/
    
  5. Increase the memory allocated to Tomcat, which you will need for running complex queries in GeoServer (the values here may not be applicable for every installation):

    $ cd $CATALINA_HOME/bin
    $ echo 'CATALINA_OPTS="-Xmx2g -XX:MaxPermSize=128m"' >> setenv.sh
    
  6. Start Tomcat, either as a service or through the startup scripts, and ensure that GeoServer is available at http://localhost:8080/geoserver/web/.

Create the Accumulo Data Store and Layer in GeoServer

Log into GeoServer using your user and password credentials. Click “Stores” and “Add new Store”. Select the Accumulo (GeoMesa) vector data source, and fill in the required parameters.

Basic store info:

  • workspace this is dependent upon your GeoServer installation
  • data source name pick a sensible name, such as geomesa_authorizations
  • description this is strictly decorative; GeoMesa authorizations tutorial

Connection parameters:

  • these are the same parameter values that you supplied on the command line when you ran the tutorial; they describe how to connect to the Accumulo instance where your data reside
  • geomesa.security.auths leave this field empty

Click “Save”, and GeoServer will search your Accumulo table for any GeoMesa-managed feature types.

Publish the Layer

GeoServer should recognize the gdelt-secure feature type, and should present that as a layer that can be published. Click on the “Publish” link.

You will be taken to the “Edit Layer” screen. You will need to enter values for the data bounding boxes. In this case, you can click on the link to compute these values from the data.

Click on the “Save” button when you are done.

Configure GeoServer for PKI Login

Follow the instructions in the GeoServer documentation in order to enable PKI login to GeoServer.

In the step where you add the ‘cert’ filter to the ‘Filter Chains’, also add it to the ‘rest’, ‘gwc’ and ‘default’ chains (in addition to web).

We will be using the ‘rod’ and ‘scott’ users, so be sure to install those into your browser.

Warning

Make sure that you click the ‘Save’ button on all GeoServer screens. Otherwise, your changes may be lost.

Verify that the changes were applied by re-starting Tomcat, and checking that the ‘web’ filter chain has the ‘cert’ filter selected:

Web Filter Panel

Web Filter Panel

Install an LDAP Server for Storing Authorizations

Note

If you are already have an LDAP server set up, you can skip this step.

  1. Download and install ApacheDS
  2. Either run as a service, or run through the start scripts:
$ cd apacheds-2.0.0-M20/bin
$ chmod 755 *.sh
$ ./apacheds.sh

Configure LDAP for Storing Authorizations

We want to configure LDAP with a user to match the Spring Security PKIs we are testing with. The end result we want is to create the following user:

DN: cn=rod,ou=Spring Security,o=Spring Framework

In order to do that, we will use Apache Directory Studio.

  1. Download and run Apache Directory Studio.
  2. Connect to the your LDAP instance (ApacheDS), using the instructions here (note: you do not need to change the password unless you want to).
  3. Create a partition for our data:
    1. Right-click the ‘ApacheDS (localhost)’ entry under the ‘Connection’ tab and select ‘Open Configuration’.
    2. Click ‘Advanced Partitions Configuration…’.
    3. Click ‘Add’.
    4. Set the ID field to be ‘Spring Framework’.
    5. Set the Suffix field to be ‘o=Spring Framework’.
    6. Uncheck ‘Auto-generate context entry from suffix DN’.
    7. Set the following attributes in Context Entry:
      • objectclass: extensibleObject
      • objectclass: top
      • objectclass: domain
      • dc: Spring Framework2
      • o: Spring Framework2
    8. Hit Ctrl-s to save the partition. ApacheDS Partition
  4. Restart ApacheDS. Otherwise the partition will not be available and the LDIF import will fail.
  5. Load the following LDIF file, which will create the Spring Security OU and the ‘rod’ user:
    • spring-security-rod.ldif
    • Right-click the ‘Root DSE’ node in the LDAP browser, and select ‘Import->LDIF import…’

Test LDAP Connection Using Tutorial Code

The tutorial code includes an AuthorizationsProvider implementation that will connect to LDAP to retrieve authorizations, in the class com.example.geomesa.auths.LdapAuthorizationsProvider.

The provider will configure itself based on the geomesa-ldap.properties file on the classpath (under src/main/resources):

# ldap connection properties
java.naming.factory.initial=com.sun.jndi.ldap.LdapCtxFactory
java.naming.provider.url=ldap://localhost:10389
java.naming.security.authentication=simple
java.naming.security.principal=uid=admin,ou=system
java.naming.security.credentials=secret

# the ldap node to start the query from
geomesa.ldap.search.root=o=Spring Framework
# the query that will be applied to find the user's record
# the '{}' will be replaced with the common name from the certificate the user has logged in with
geomesa.ldap.search.filter=(&(objectClass=person)(cn={}))
# the ldap attribute that holds the comma-delimited authorizations for the user
geomesa.ldap.auths.attribute=employeeType

The default file included with the tutorial will connect to the LDAP instance we set up in the previous steps. If you are using a different LDAP configuration, you will need to modify the file appropriately.

The LdapAuthorizationsProvider will look for a particular LDAP attribute that stores the user’s authorizations in a comma-delimited list. For simplicity, in this tutorial we have re-purposed an existing attribute, employeeType. The attribute to use can be modified through the property file.

When we inserted the ‘rod’ record into LDAP, we set his employeeType to ‘user,admin’, corresponding to our Accumulo authorizations. If you are using different authorizations, you will need to update the attribute to match.

The tutorial code includes a test case for connecting to LDAP, in the class LdapAuthorizationsProviderTest.

Once you have modified geomesa-ldap.properties to connect to your LDAP, you can test the connection by running this test class:

$ java -cp geomesa-tutorials-accumulo/geomesa-tutorials-accumulo-authorizations/target/geomesa-tutorials-accumulo-authorizations-${geomesa.version}.jar \
    org.geomesa.example.accumulo.auths.LdapAuthorizationsProviderTest rod

The argument to the program (‘rod’) is the user to retrieve authorizations for. You should get the following output:

Checking auths from LDAP for user 'rod'
Retrieved auths: user,admin

Installing the LDAP AuthorizationProvider in GeoServer

In order to use the LdapAuthorizationsProvider, we need to install it as a service provider into GeoServer, where it will automatically be picked up by GeoMesa.

The tutorial code includes a service provider registry in the META-INF/services folder. By default, the provider class is specified as the EmptyAuthorizationsProvider.

  1. Ensure that your LDAP configuration is correct by running LdapAuthorizationsProviderTest, as described above.

  2. Change the provider class in the single line file src/main/resources/META-INF/services/org.locationtech.geomesa.security.AuthorizationsProvider to be org.geomesa.example.accumulo.auths.LdapAuthorizationsProvider

  3. Rebuild the tutorial JAR and install the unshaded original jar in GeoServer:

    $ mvn clean install -pl geomesa-tutorials-accumulo/geomesa-tutorials-accumulo-authorizations
    $ cp geomesa-tutorials-accumulo/geomesa-tutorials-accumulo-authorizations/target/geomesa-tutorials-accumulo-authorizations-${geomesa.version}.jar \
        /path/to/tomcat/webapps/geoserver/WEB-INF/lib/
    

Note

We want to use the unshaded jar since all the required dependencies are already installed in GeoServer.

  1. Restart GeoServer (or start it if it is not running).

At this point you should have everything configured and in-place.

Verifying the LDAP Authorizations in GeoServer

In order to verify that the authorizations are working correctly, execute a query against GeoMesa by calling the WMS provider over HTTPS in your browser:

https://localhost:8443/geoserver/wms?service=WMS&version=1.1.0&request=GetMap&layers=geomesa:gdelt_auths&styles=&bbox=31.6,44,37.4,47.75&width=1200&height=600&srs=EPSG:4326&format=application/openlayers

When prompted, select the ‘rod’ certificate.

You should see the normal data come back, with many red points indicating the data:

Authorized Results

Authorized Results

Now try the same query, but use the ‘scott’ certificate. This time, there should be no data returned, as the ‘scott’ user does not have any authorizations set up in LDAP.

Note

A simple way to use different certificates at once is to open multiple ‘incognito’ or ‘private’ browser windows.