10.8 The Dirmngr Client Tool

The dirmngr-client is a simple tool to contact a running dirmngr and test whether a certificate has been revoked — either by being listed in the corresponding CRL or by running the OCSP protocol. If no dirmngr is running, a new instances will be started but this is in general not a good idea due to the huge performance overhead.

The usual way to run this tool is either:

dirmngr-client acert

or

dirmngr-client <acert

Where acert is one DER encoded (binary) X.509 certificates to be tested. The return value of this command is

0

The certificate under question is valid; i.e., there is a valid CRL available and it is not listed there or the OCSP request returned that that certificate is valid.

1

The certificate has been revoked

2 (and other values)

There was a problem checking the revocation state of the certificate. A message to stderr has given more detailed information. Most likely this is due to a missing or expired CRL or due to a network problem.

dirmngr-client may be called with the following options:

--version

Print the program version and licensing information. Note that you cannot abbreviate this command.

--help, -h

Print a usage message summarizing the most useful command-line options. Note that you cannot abbreviate this command.

--quiet, -q

Make the output extra brief by suppressing any informational messages.

-v

--verbose

Outputs additional information while running. You can increase the verbosity by giving several verbose commands to DIRMNGR, such as ‘-vv’.

--pem

Assume that the given certificate is in PEM (armored) format.

--ocsp

Do the check using the OCSP protocol and ignore any CRLs.

--force-default-responder

When checking using the OCSP protocol, force the use of the default OCSP responder. That is not to use the Responder as given by the certificate.

--ping

Check whether the dirmngr daemon is up and running.

--cache-cert

Put the given certificate into the cache of a running dirmngr. This is mainly useful for debugging.

--validate

Validate the given certificate using dirmngr’s internal validation code. This is mainly useful for debugging.

--load-crl

This command expects a list of filenames with DER encoded CRL files. With the option --url URLs are expected in place of filenames and they are loaded directly from the given location. All CRLs will be validated and then loaded into dirmngr’s cache.

--lookup

Take the remaining arguments and run a lookup command on each of them. The results are Base-64 encoded outputs (without header lines). This may be used to retrieve certificates from a server. However the output format is not very well suited if more than one certificate is returned.

--url

-u

Modify the lookup and load-crl commands to take an URL.

--local

-l

Let the lookup command only search the local cache.

--squid-mode

Run DIRMNGR-CLIENT in a mode suitable as a helper program for Squid’s external_acl_type option.