Configure Nexus OCSP Responder

This article is valid for Nexus OCSP Responder 6.2 and later.

This article and its sub-articles describe how to configure Nexus OCSP Responder. When running the Nexus OCSP Responder, the application will read files (for example, configuration and truststore) from <configuration root>.

Prerequisites

Installed Nexus OCSP Responder.

Open the configuration file

Open the configuration file ocsp.conf for editing:
1. On Windows, the path to the <configuration root> is chosen during installation and is defined in the string registry key named Arguments in the following Windows registry path:
  HKEY_LOCAL_MACHINE\SOFTWARE\Nexus\Service Parameters\OCSP
2. On Linux, the path to the <configuration root> is defined in <install root>/bin/nexus-ocsp.conf by the following parameter:
  SERVICEARGUMENTS='-p <configuration root>
You can manually change the path after the installation by redefining the path parameter to point to a new configuration root directory.

Mandatory settings

In the configuration file, each main configurable entity has its own section. The corresponding parameter names are built up with prefixes associated with the entity.

Do the mandatory settings in the OCSP configuration file:

Configurable Entity	Description	Prefix
Trust store	The trust store is a file containing certificates for all trusted CAs.	`ocsp.trust`
Certificate cache	The certificate cache is a cache directory where "non-trusted" certificates are stored.	`ocsp.certs`
Validation	A certificate can be validated by checking for revocation data locally in a CRL or CIL cache.	`ocsp.validation`
OCSP responder	OCSP responders are preconfigured with different semantics. First make your choice between the preconfigurations, then specify the details for each responder.	`responder`
Key management	Keys are specified together with the configuration that uses them. The keys may be located in software tokens and in 3rd party devices.	`key`
System management	The agent is responsible for the communication with an existing system monitor (when used) and for logging.	`agent`

Optional settings

Do the other settings in the OCSP configuration file (optional).

Configurable Entity	Description	Prefix
Certificate lookup (optional)	If a required certificate cannot be found in the cache, it may be searched in specified directories.	`ocsp.certs`
Back end client (optional)	Certificates can be validated by use of external OCSP responders. The OCSP client that should send the requests, will use several methods to find the responder URLs.	`ocsp.client`
OCSP response cache (optional)	The response cache is a cache where responses from external OCSP responders can be stored.	`ocsp.cache`

Configuration

See these articles for configuration of Nexus OCSP Responder:

Trust store

Certificate cache section

Certificate lookup section

Back end client section

OCSP response cache section

Validation section

OCSP responder section

Key management section

System management section

Revocation information

Default OCSP configuration

Set up hardware token

Descriptions and workflow

The articles that are gathered here: Nexus OCSP Responder descriptions and workflow include descriptions for various concepts used within Nexus OCSP Responder and also some useful workflows.

General information

Specify file paths

Full path

You can specify a full path to a file or a directory, such as ocsp.trust.store=C:\Program Files\Nexus\OCSP Responder\certs\trust.store.

Relative path

Alternatively, specify a relative path (default): ocsp.trust.store=certs/trust.store ("/" makes the specification OS-independent)

On both Windows and Linux environments, the relative path will start from the <configuration root> directory.

Case sensitivity

Entity	Case sensitive
Configuration parameter names	No
File names	Yes (when appearing as values, that is, on the right hand side of an "=")
LDAP searchbase and filters	Yes (when appearing as values, that is, on the right hand side of an "=")
Distinguished name patterns used for certificate matching	Yes (when appearing as values, that is, on the right hand side of an "=")
URLs	Yes (when appearing as values, that is, on the right hand side of an "=")
Constants and types	No

After updates

When you have done configuration updates, restart Nexus OCSP Responder.

Encryption of sensitive configuration parameters

To scramble any configuration parameter in the configuration file, add the keyword encrypted to the parameter definition in the configuration. The next time the application starts, it scans the configuration file for unscrambled values and scrambles the value. The updated configuration file is saved to disk.

For example: *.pin = 1234 is considered to be sensitive and should therefore be scrambled.

To scramble the parameter, replace the parameter with *.pin.encrypted = 1234.
The server will find the unscrambled value and scramble it.
In the resulting configuration file the parameter is rewritten to *.pin.encrypted = encrypted:MCa12== for example.