AppSuite:OX Guard

OX Guard

OX Guard is a fully integrated security add-on to OX App Suite that provides end users with a flexible email and file encryption solution. OX Guard is a highly scalable, multi server, feature rich solution that is so simple-to-use that end users will actually use it. With a single click a user can take control of their security and send secure emails and share encrypted files. This can be done from any device to both OX App Suite and non-OX App Suite users.

OX Guard uses standard PGP encryption for the encryption of email and files. PGP has been around for a long time, yet has not really caught on with the masses. This is generally blamed on the confusion and complications of managing the keys, understanding trust, PGP format types, and lack of trusted central key repositories. Guard simplifies all of this, making PGP encryption as easy as a one click process, with no keys to keep track of, yet the options of advanced PGP management for those that know how.

This article will guide you through the installation of Guard and describes the basic configuration and software requirements. As it is intended as a quick walk-through it assumes an existing installation of the operating system including a single server App Suite setup as well as average system administration skills. This guide will also show you how to setup a basic installation with none of the typically used distributed environment settings. The objective of this guide is:

• To setup a single server installation
• To setup a single Guard instance on an existing Open-Xchange installation, no cluster
• To use the database service on the existing Open-Xchange installation for Guard, no replication
• To provide a basic configuration setup, no mailserver configuration

Key features

• Simple security at the touch of a button
• Provides user based security - Separate from provider
• Supplementary security to Provider based security - Layered
• Powerful features yet simple to use and understand
• Security - Inside and outside of the OX environment
• Email and Drive integration
• Uses proven PGP security

Availability

If an OX App Suite customer would like to evaluate OX Guard integration, the first step is to contact OX Sales. OX Sales will then work on the request and send prices and license/API (for the hosted infrastructure) key details to the customer.

Requirements

Please review following URL for remaining requirements

Please review OX Guard Requirements for a full list of requirements.

Since OX Guard is a Microservice it can either be added to an existing Open-Xchange installation or it can be deployed on a dedicated environment without having any of the other Open-Xchange App Suite core services installed. OX App Suite v7.6.0 or later is required to operate this extension both in a single or multi server environments.

Prerequisites:

• Open-Xchange REST API
• Grizzly HTTP connector (open-xchange-grizzly)
• A supported Java Virtual Machine (Java 7)
• An Open-Xchange App Suite installation v7.6.0 or later
• Please Note: To get access to the latest minor features and bug fixes, you need to have a valid license. The article Updating OX-Packages explains how that can be done.

Important Notes

Customization

OX Guard version supports branding / theming using the configuration cascade, defining a templateID for a user or context. Additional details will be provided in customization documentation. Check bottom of this page.

Mail Resolver

READ THIS VERY CAREFULLY; BEFORE PROCEEDING WITH GUARD INSTALLATION!

The Guard installation must be able to determine if an email recipient is a local OX user or if it should be a guest account. The default MailResolver uses the context domain name to do this. On many installations, domains may extend across multiple context and multiple database shards. In these cases, the default MailResolver won't work. In addition, if a custom authentication package is used, the Mail Resolver will likely not work.

Be sure to test the mail resolver using

/opt/open-xchange/guard/sbin/guard test email@domain 

to see if the mail Resolver works.

If the test does not work, you will likely need a custom Mail Resolver. Please see Mail Resolver page

This resolver software depends heavily on your local deployment.

Download and Installation

General

The installation of the open-xchange-rest package which is required for Guard will eventually execute database update tasks if installed and activated. Please take this into account.

Redhat Enterprise Linux 6 or CentOS 6

If not already done, add the following repositories to your Open-Xchange yum configuration:

 [open-xchange-guard-stable-guard]
name=Open-Xchange-guard-stable-guard
baseurl=https://software.open-xchange.com/products/guard/stable/guard/RHEL6/
gpgkey=https://software.open-xchange.com/oxbuildkey.pub
enabled=1
gpgcheck=1
metadata_expire=0m

and run

$ yum update
$ yum install open-xchange-rest open-xchange-guard open-xchange-guard-ui open-xchange-guard-ui-static

Debian GNU/Linux 7.0

If not already done, add the following repositories to your Open-Xchange apt configuration:

deb https://software.open-xchange.com/products/guard/stable/guard/DebianWheezy /

and run

$ apt-get update
$ apt-get install open-xchange-rest open-xchange-guard open-xchange-guard-ui open-xchange-guard-ui-static

SUSE Linux Enterprise Server 11

Add the package repository using zypper if not already present:

$ zypper ar https://software.open-xchange.com/products/guard/stable/guard/SLES11 guard-stable-guard

and run

$ zypper ref
$ zypper in open-xchange-rest open-xchange-guard open-xchange-guard-ui open-xchange-guard-ui-static

Guard requires Java 1.7, which will be installed through the Guard packages, still SUSE Linux Enterprise Server 11 will not use Java 1.7 by default. Therefor we have to set Java 1.7 as the default instead of Java 1.6:

$ update-alternatives --config java

Now select the Java 1.7 JRE, example:

There are 2 alternatives which provide `java'.

  Selection    Alternative
-----------------------------------------------
*         1    /usr/lib64/jvm/jre-1.6.0-ibm/bin/java
 +        2    /usr/lib64/jvm/jre-1.7.0-ibm/bin/java

Press enter to keep the default[*], or type selection number: 2
Using '/usr/lib64/jvm/jre-1.7.0-ibm/bin/java' to provide 'java'.

Univention Corporate Server

If you have purchased the OX App Suite for UCS, the OX Guard is part of the offering. OX Guard is available in the Univention App Center. Please check the UMC module App Center for the installation of the OX Guard at your already available environment.

Please note: By default, OX Guard generates the link to the secure content for external recipients on the basis of the local fully qualified domain name (FQDN). If the local FQDN is not reachable from the internet, it has to be specified manually. This can be done by setting a UCR variable, e.g. via the UMC module "Univention Configuration Registry". The variable has to contain the external FQDN of the OX Guard system:

oxguard/cfg/guard.properties/com.openexchange.guard.externalEmailURL=HOSTNAME.DOMAINNAME

Update OX Guard

Before upgrading Guard to version 2.0.0 you need to install the package open-xchange-guard-backend on all groupware nodes used by Guard throught the REST api. In other words, every groupware node have open-xchange-rest installed, now needs to have open-xchange-guard-backend installed.

Redhat Enterprise Linux 6 or CentOS 6

If not already done, add the following repositories to your Open-Xchange yum configuration:

 [open-xchange-guard-stable-guard-updates]
name=Open-Xchange-guard-stable-guard-updates
baseurl=https://LDBUSER:LDBPASSWORD@software.open-xchange.com/products/guard/stable/guard/updates/RHEL6/
gpgkey=https://software.open-xchange.com/oxbuildkey.pub
enabled=1
gpgcheck=1
metadata_expire=0m

and run

$ yum update
$ yum upgrade

After the new packages are installed, the guard process needs a restart:

$ /etc/init.d/open-xchange-guard restart

Debian GNU/Linux 7.0

If not already done, add the following repositories to your Open-Xchange apt configuration:

deb https://LDBUSER:LDBPASSWORD@software.open-xchange.com/products/guard/stable/guard/updates/DebianWheezy /

Then run

$ apt-get update
$ apt-get dist-upgrade

If you want to see, what apt-get is going to do without actually doing it, you can run:

$ apt-get dist-upgrade -s

After the new packages are installed, the guard process needs a restart:

$ /etc/init.d/open-xchange-guard restart

SUSE Linux Enterprise Server 11

Add the package repository using zypper if not already present:

$ zypper ar https://LDBUSER:LDBPASSWORD@software.open-xchange.com/products/guard/stable/guard/updates/SLES11 guard-stable-guard-updates

and run

$ zypper dup -r guard-stable-guard-backend-updates
$ zypper dup -r guard-stable-guard-ui-updates

You might need to run

$ zypper ref

to update the repository metadata before running zypper up.

After the new packages are installed, the guard process needs a restart:

$ open-xchange-guard restart

Univention Corporate Server

If you have purchased the OX App Suite for UCS, the OX Guard is part of the offering. OX Guard is available in the Univention App Center. Please check the UMC module App Center for the update of the OX Guard.

Update OX Guard v1.2 to OX Guard v2.0.0

If you have an existing Guard v1.2 database, and are upgrading to v2.0, additional PGP key table need to be created and populated. Once the Guard package has been updated, type

/opt/open-xchange/guard/sbin/guard upgradePGP

This process will alter the needed database tables and populate the needed lookup tables. Guard 1.2 can continue to run in the background. Once complete, Guard 2.0 can be started.

Configuration

The following gives an overview of the most important settings to enable Guard for users on the Open-Xchange installation. Some of those settings have to be modified in order to establish the database and REST API access from the Guard service. All settings relating to the Guard backend component are located in the configuration file guard.properties located in /opt/open-xchange/guard/etc. The default configuration should be sufficient for a basic "up-and-running" setup (with the exception of defining the database username and password). Please refer to the inline documentation of the configuration file for more advanced options. Additional information can be found here Guard Configuration

$ vim /opt/open-xchange/guard/etc/guard.properties

Open-Xchange config_db host - Guard will establish a connection to the config_db

com.openexchange.guard.configdbHostname=localhost

Guard database for storing user keys

com.openexchange.guard.oxguardDatabaseHostname=localhost

Username and Password for the two databases above

com.openexchange.guard.databaseUsername=openexchange
com.openexchange.guard.databasePassword=db_password

Open-Xchange REST API host

com.openexchange.guard.restApiHostname=localhost

Open-Xchange REST API username and password (need to be defined in the OX backend in the "Configure services" below)

com.openexchange.guard.restApiUsername=apiusername
com.openexchange.guard.restApiPassword=apipassword

External URL for this Open-Xchange installation. This setting will be used to generate the link to the secure content for external recipients

com.openexchange.guard.externalEmailURL=URL_TO_OX

Configure services

Apache

Configure the mod_proxy_http module by adding the Guard API.

Redhat Enterprise Linux 6 or CentOS 6

$ vim /etc/httpd/conf.d/proxy_http.conf

Debian GNU/Linux 7.0 and SUSE Linux Enterprise Server 11

$ vim /etc/apache2/conf.d/proxy_http.conf

<Proxy balancer://oxguard>
       Order deny,allow
       Allow from all

       BalancerMember http://localhost:8080/oxguard timeout=1800 smax=0 ttl=60 retry=60 loadfactor=100 route=OX1
       ProxySet stickysession=JSESSIONID|jsessionid scolonpathdelim=ON
       SetEnv proxy-initial-not-pooled
       SetEnv proxy-sendchunked
</Proxy>


ProxyPass /appsuite/api/oxguard balancer://oxguard

Please Note: The Guard API settings must be inserted before the existing “<Proxy /appsuite/api>” parameter.

After the configuration is done, restart the Apache webserver

$ apachectl restart

Open-Xchange

Starting in Guard 2.0, there is an administrative component to the Open-Xchange backend that notifies Guard when a user or context is deleted. Install the package open-xchange-guard-backend on all OX backend servers. On a debian install, this command would be:

apt-get install open-xchange-guard-backend

There is also a configuration file for the OX backend regarding some general Guard settings. Please remove comments in front of the following settings to the configuration file guard.properties on the Open-Xchange backend servers:

$ vim /opt/open-xchange/etc/guard.properties

# OX GUard general permission, required to activate Guard in the AppSuite UI.
com.openexchange.capability.guard=true

# Default theme template id for all users that have no custom template id configured.
com.openexchange.guard.templateID=0

Configure the API username and password that you assigned to Guard in the server.properties file

$ vim /opt/open-xchange/etc/server.properties

# Specify the user name used for HTTP basic auth by internal REST servlet
com.openexchange.rest.services.basic-auth.login=apiusername

# Specify the password used for HTTP basic auth by internal REST servlet
com.openexchange.rest.services.basic-auth.password=apipassword

Finally, the OX backend needs to know where the Guard server is located. This is used to notify the Guard server of changes in users, and to send emails marked for signature. The URL for the Guard server should include the url suffix /guardadmin

$ vim /opt/open-xchange/etc/guard.properties

# Specifies the URI to the OX Guard end-point; e.g. http://guard.host.invalid:8081/guardadmin
# Default is empty
com.openexchange.guard.endpoint=http://guardserver:8080/guardadmin

Restart the OX backend

$ /etc/init.d/open-xchange restart

SELinux

Running SELinux prohibits your local Open-Xchange backend service to connect to localhost:8080, which is where the Guard backend service listens to. In order to allow localhost connections to 8080 execute the following:

$ setsebool -P httpd_can_network_connect 1

Initiating the Guard database and key store

Once the Guard configuration (database and backend configuration) and the service configuration has been applied, the Guard administration script needs to be executed in order to create the Guard databases. The administration script also takes care of the creation of the master keys and the master password file in /opt/open-xchange/guard. The initiation only needs to be done once for a multi server setup, for details please see “Optional / Clustering”.

Please Note: If you run a cluster of OX / Guard nodes, only execute this command on ONE node. Not on all nodes! See Ox Guard Clustering for details.

/opt/open-xchange/guard/sbin/guard init

Please Note: It is important to understand that the master password file located at /opt/open-xchange/guard/oxguardpass is required to reset user passwords, without them the administrator will not be able to reset user passwords anymore in the future. The file contains the passwords used to encrypt the master database key, as well as passwords used to encrypt protected data in the users table. It must be the same on all Guard servers.

Test Setup

Not required, but it is a good idea to test the Guard setup before starting the initialization. The test function will verify that Guard has a good connection to the OX backend, and that it can resolve email addresses to users.

To test, use an email address that exists on the OX backend (john@example.com for this example)

/opt/open-xchange/guard/sbin/guard test john@example.com

Guard should return information from the OX backend regarding the user associated with john@example.com. Problems resolving information for the user should be resolved before using Guard. Check Rest API passwords and settings if errors returned.

Start Guard

The services have been configured and the database has been initiated, it's time to start Guard

$ /etc/init.d/open-xchange-guard start

Enabling Guard for Users

Guard provides two capabilities for users in the environment as well as a basic "core" level:

• Guard: com.openexchange.capability.guard
• Guard Mail: com.openexchange.capability.guard-mail
• Guard Drive: com.openexchange.capability.guard-drive

The "core" Guard enabled a basic read functionality for Guard encrypted emails. We recommend enabling this for all users, as this allows all recipients to read Guard emails sent to them. Great opportunity for upsell. Recipients with only Guard enabled can then do a secure reply to the sender, but they can't start a new email or add recipients.

"Guard Mail" and "Guard Drive" are additional options for users. "Guard Mail" allows users the full functionality of Guard emails. "Guard Drive" allows for encryption and decryption of drive files.

Each of those two Guard components is enabled for all users that have the according capability configured. Please note that users need to have the Drive permission set to use Guard Drive. So the users that have Guard Drive enabled must be a subset of those users with OX Drive permission. Since v7.6.0 we enforce this via the default configuration. Those capabilities can be activated for specific user by using the Open-Xchange provisioning scripts:

Guard Mail:

$ /opt/open-xchange/sbin/changeuser -c 1 -A oxadmin -P admin_password -u testuser --config/com.openexchange.capability.guard-mail=true

Guard Drive:

$ /opt/open-xchange/sbin/changeuser -c 1 -A oxadmin -P admin_password -u testuser --config/com.openexchange.capability.guard-drive=true

Please Note: Guard Drive requires Guard Mail to be configured for the user as well. In addition, these capabilities may be configured globally by editing the guard.properties file on the OX bakend

Optional

SSL Configuration

Per default the connection between the Guard backend and the configured Open-Xchange REST API host is unencrypted. Even though that Guard will never transmit unencrypted emails to or from the REST API you can optionally encrypt the whole communication between those two components by using SSL. To enforce Guard to use SSL in the communication between those two components enable the follwing configuration in Guard configuration file.

 $ vim /opt/open-xchange/guard/etc/guard.properties

 com.openexchange.guard.backend_ssl=true

The Guard backend is most commonly placed behind a load balancer (APACHE or other) and defaults to HTTP for incoming and outgoing traffic, using the load balancer to do SSL with the users. If you want Guard to use SSL for all communications, you need to set up the SSL key to use.

Please note that you have to provide access to the certificates.

com.openexchange.guard.useSSL: true
com.openexchange.guard.SSLPort: 8443
com.openexchange.guard.SSLKeyStore: //keystore location//
com.openexchange.guard.SSLKeyName: //alias name here//
com.openexchange.guard.SSLKeyPass: //ssl password//

Please Note: Enabling SSL might decrease performance and/or create more system load due to additional encoding of the HTTP streams.

For details on SSL installation and configuration, please see OX Guard SSL Installation

Recipient key detection

Local

Guard needs to determine if an email recipients email address is an internal or external (non-ox) user.

To detect if the recipient is an account on the same OX Guard system there is a mechanism needed to map a recipient mail address to the correct local OX context. The default implementation delivered in the product achieves that by looking up the mail domain (@example.com) within the list of context mappings. That is at least not possible in case of ISPs where different users/contexts use the same mail domain. In case your OX system does not use mail domains in context mappings it is required to deploy an OX OSGi bundle implementing the com.openexchange.mailmapping.MailResolver class or by interfacing Guard with your mail resolver system. Please see OX Guard Mail Resolver for details

External

Starting with Guard 2.0, Guard will use public PGP Key servers if configured to find PGP Public keys. In addition, Guard will also look up SRV records for PGP Key servers for a recipients domain. This follows the standards OpenPGP Draft.

External PGP servers to use can be configured in the guard.properties file on the Guard servers.

com.openexchange.guard.publicPGPDirectory = hkp://keys.gnupg.net:11371, hkp://pgp.mit.edu:11371

If you would like this Guard installation discoverable by other Guard servers, then create a SRV record for each domain ("example.com" in this illustration)

_hkp._tcp.example.com

You will also need to make additional entries in the apache proxy_http.conf file.

<Proxy balancer://oxguardpgp>
       Order deny,allow
       Allow from all, add
       BalancerMember http://guardserver:8080/pgp timeout=1800 smax=0 ttl=60 retry=60 loadfactor=50 route=OX3
       ProxySet stickysession=JSESSIONID|jsessionid scolonpathdelim=ON
       SetEnv proxy-initial-not-pooled
       SetEnv proxy-sendchunked
  </Proxy>

<Proxy /pks>
       ProxyPass balancer://oxguardpgp
</Proxy>

Please Note PGP Public key servers by default append use the url server/pks when the record is obtained from a SRV record. The proxy above routes anything with the apache domain/pks to the Oxguard PGP server

Clustering

You can run multiple OX Guard servers in your environment to ensure high availability or enhance scalability. OX Guard integrates seamlessly into the existing Open-Xchange infrastructure by using the existing interface standards and is therefor transparent to the environment. A couple of things have to be prepared in order to loosely couple OX Guard servers with Open-Xchange servers in a cluster.

MySQL

The MySQL servers need to be configured in order to allow access to the configdb of Open-Xchange. To do so you need to set the following configuration in the MySQL my.cnf:

bind = 0.0.0.0

This allows the Guard backend to bind to the MySQL host which is configured in the guard.properties file with com.openexchange.guard.configdbHostname. After the bind for the MySQL instance is configured and the OX Guard backend would be able to connect to the configured host, you have to grant access for the OX Guard service on the MySQL instance to manage the databases. Do so by connecting to the MySQL server via the mysql client. Authenticate if necessary and execute the following, please note that you have to modify the hostname / IP address of the client who should be able to connect to this database, it should include all possible OX Guard servers:

GRANT ALL PRIVILEGES ON *.* TO 'openexchange'@'oxguard.example.com' IDENTIFIED BY ‘secret’;

Apache

OX Guard uses the Open-Xchange REST API to store and fetch data from the Open-Xchange databases. The REST API is a servlet running in the Grizzly container. By default it is not exposed as a servlet through Apache and is only accessibly via port 8009. In order to use Apache's load balancing via mod_proxy we need to add a servlet called "preliminary" to proxy_http.conf, example based on a clustered mod_proxy configuration:

<Location /preliminary>
     Order Deny,Allow
     Deny from all
     # Only allow access from Guard servers within the network. Do not expose this
     # location outside of your network. In case you use a load balancing service in front
     # of your Apache infrastructure you should make sure that access to /preliminary will
     # be blocked from the internet / outside clients. Examples:
     # Allow from 192.168.0.1
     # Allow from 192.168.1.1 192.168.1.2
     # Allow from 192.168.0.
     ProxyPass /preliminary balancer://oxcluster/preliminary
</Location>

Make sure that the balancer is properly configured in the mod_proxy configuration. Examples on how to do so can be found in our clustering configuration for Open-Xchange AppSuite. Like explained in the example above, please make sure that this location is only available in your internal network, there is no need to expose /preliminary to the public, it is only used by Guard servers to connect to the OX backend. If you have a load balancer in front of the Apache cluster you should consider blocking access to /preliminary from WAN to restrict access to the servlet to internal network services only.

Now add the OX Guard BalancerMembers to the oxguard balancer configuration (also in proxy_http.conf) to address all your OX Guard nodes in the cluster in this balancer configuration. The configuration has to be applied to all Apache nodes within the cluster.

If the Apache server is a dedicated server / instance you also have to install the OX Guard UI-Static package on all Apache nodes in the cluster in order to provide static files like images or CSS to the OX Guard client. Example for Debian (the OX Guard repository has to be configured in the package management prior):

$ apt-get install open-xchange-guard-ui-static

Open-Xchange

Disable the Open-Xchange IPCheck for session verification. This is required because OX Guard will use the users session cookie to connect to the Open-Xchange REST API, but as a different IP address than the OX Guard server has been used during authentication the request would fail if you don't disable the IPCheck:

$ vim /opt/open-xchange/etc/server.properties

and set:

com.openexchange.IPCheck=false

The OX Guard UI package has to be installed on all Open-Xchange backend nodes as well, example for Debian (the OX Guard repository has to be configured in the package management prior):

$ apt-get install open-xchange-guard-ui

Restart the Open-Xchange service afterwards.

OX Guard

For details in clustering Guard servers, please see OxGuard Clustering . It is critical that all Guard servers have the same oxguardpass file. Please see the clustering link for details. Do not run ./guard init on more than one server.

After all the services like MySQL, Apache and Open-Xchange have been configured you need to update the OX Guard backend configuration to point to the correct API endpoints. Set the REST API endpoint to an Apache server by setting the following value in /opt/open-xchange/guard/etc/guard.properties:

com.openexchange.guard.restApiHostname=apache.example.com

Per default Guard will try to connect to port 8009 to this host, but as we configured the REST API to be proxies thorugh the serblet /preliminary on every Apache we now also need to change the target port for the REST API. You can do so by adding the following line into /opt/open-xchange/guard/etc/guard.properties:

com.openexchange.guard.oxBackendPort=80

Please also change all settings in regards to MySQL like com.openexchange.guard.configdbHostname, com.openexchange.guard.oxguardDatabaseHostname, com.openexchange.guard.databaseUsername or com.openexchange.guard.databasePassword. Afterwards restart the OX Guard service and check the logfile if the OX Guard backend is able to connect to the configured REST API.

Support API

The OX Guard Support API enables administrative access to various functions for maintaining OX Guard from a client in a role as a support employee. The OX Guard support API is accessible using: /guardsupport. A client has to do a BASIC AUTH authentication in order to access the API. Username and password can be configured in the guard.properties file using the following settings:

   # Specify the username and password for accessing the Support API of Guard
   com.openexchange.guard.supportapiusername=
   com.openexchange.guard.supportapipassword=

Reset password

POST /guardsupport/?action=reset_password

Performs a password reset and sends a new random generated password to a specified email address by the user or a default address if the user did not specify an email address.

Since Guard 2.0

Parameters:

• email – The email address of the user to reset the password for
• default (optional) – The email address to send the new password to, if the user did not specify a secondary email address

Expose key

POST /guardsupport/?action=expose_key

Marks a deleted user key temporary as “exposed” and creates a unique URL for downloading the exposed key. Automatic resetting of exposed keys to "not exposed" is scheduled once a day and resets all exposed keys which have been exposed before X hours, where X can be configured using com.openexchange.guard.exposedKeyDurationInHours in the guard.properties files.

Since Guard 2.0

Parameters:

• email – The email address of the user to expose the deleted keys for
• cid – The context id

Response: An URL pointing to the downloadable exposed keys

Delete user

POST /guardsupport/?action=delete_user

Deletes all keys related to a certain user. The keys are backed up and can be exposed using the “expose_key” call.

Since Guard 2.0

Parameters:

• user_id – The user's id
• cid - The context id

Customization

Guard's templates are customizable at the user and context level. Please see Customization for details

Entropy

Guard requires entropy (randomness) to generate the private/public keys that are used. Depending on the server and it's environment, this may become a problem. Please see Entropy for a possible solution