- CRL and OCSP daemon
Since version 2.1 of GnuPG, dirmngr
takes care of accessing the OpenPGP
keyservers. As with previous versions it is also used as a server for managing
and downloading certificate revocation lists (CRLs) for X.509 certificates,
downloading X.509 certificates, and providing access to OCSP providers.
Dirmngr is invoked internally by gpg
, or via the
Commands are not distinguished from options except for the fact that only one
command is allowed.
- 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.
- Print a list of all available options and commands. Note that you cannot
abbreviate this command.
- Run in server mode and wait for commands on the stdin. The default
mode is to create a socket and listen for commands there. This is only
used for testing.
- Run in background daemon mode and listen for commands on a socket. This is
the way dirmngr is started on demand by the other GnuPG components.
To force starting dirmngr it is in general best to use gpgconf
- Run in the foreground, sending logs to stderr, and listening on file
descriptor 3, which must already be bound to a listening socket. This is
useful when running under systemd or other similar process supervision
schemes. This option is not supported on Windows.
- List the contents of the CRL cache on stdout. This is probably only
useful for debugging purposes.
- --load-crl file
- This command requires a filename as additional argument, and it will make
Dirmngr try to import the CRL in file into it's cache. Note, that
this is only possible if Dirmngr is able to retrieve the CA's certificate
directly by its own means. In general it is better to use gpgsm's
--call-dirmngr loadcrl filename command so that gpgsm can
- --fetch-crl url
- This command requires an URL as additional argument, and it will make
dirmngr try to retrieve and import the CRL from that url into it's
cache. This is mainly useful for debugging purposes. The
dirmngr-client provides the same feature for a running dirmngr.
- This commands shuts down an running instance of Dirmngr. This command has
currently no effect.
- This command removes all CRLs from Dirmngr's cache. Client requests will
thus trigger reading of fresh CRLs.
Note that all long options with the exception of --options
may also be given in the configuration file after stripping
off the two leading dashes.
- --options file
- Reads configuration from file instead of from the default per-user
configuration file. The default configuration file is named ‘
dirmngr.conf’ and expected in the home directory.
- --homedir dir
- Set the name of the home directory to dir. This option is only
effective when used on the command line. The default is the directory
named ‘ .gnupg’ directly below the home directory of
the user unless the environment variable GNUPGHOME has been set in
which case its value will be used. Many kinds of data are stored within
- Outputs additional information while running. You can increase the
verbosity by giving several verbose commands to dirmngr, such as
- --log-file file
- Append all logging output to file. This is very helpful in seeing
what the agent actually does. Use ‘ socket://’ to log
- --debug-level level
- Select the debug level for investigating problems. level may be a
numeric value or by a keyword:
- No debugging at all. A value of less than 1 may be used instead of the
- Some basic debug messages. A value between 1 and 2 may be used instead of
- More verbose debug messages. A value between 3 and 5 may be used instead
of the keyword.
- Even more detailed messages. A value between 6 and 8 may be used instead
of the keyword.
- All of the debug messages you can get. A value greater than 8 may be used
instead of the keyword. The creation of hash tracing files is only enabled
if the keyword is used.
How these messages are mapped to the actual debugging flags is not specified and
may change with newer releases of this program. They are however carefully
selected to best aid in debugging.
- --debug flags
- Set debugging flags. This option is only useful for debugging and its
behavior may change with a new release. All flags are or-ed and may be
given in C syntax (e.g. 0x0042) or as a comma separated list of flag
names. To get a list of all supported flags the single word
"help" can be used.
- Same as --debug=0xffffffff
- --gnutls-debug level
- Enable debugging of GNUTLS at level.
- --debug-wait n
- When running in server mode, wait n seconds before entering the
actual processing loop and print the pid. This gives time to attach a
- On some platforms dirmngr is able to detect the removal of its
socket file and shutdown itself. This option disable this self-test for
- --sh -c --csh Format the info output in daemon mode
for use with the standard Bourne shell respective the C-shell. The default
is to guess it based on the environment variable SHELL which is in
almost all cases sufficient.
- Enabling this option forces loading of expired CRLs; this is only useful
- This option switches Dirmngr and thus GnuPG into ``Tor mode'' to route all
network access via Tor (an anonymity network). Certain other features are
disabled if this mode is active.
- This option forces the use of the system's standard DNS resolver code.
This is mainly used for debugging. Note that on Windows a standard
resolver is not used and all DNS access will return the error ``Not
Implemented'' if this function is used.
- When possible use a recursive resolver instead of a stub resolver.
- --resolver-timeout n
- Set the timeout for the DNS resolver to N seconds. The default are 30
- Allow Dirmngr to connect to https://versions.gnupg.org to get the
list of current software versions. On debian-packaged versions, this
option does nothing since software updates should be handled by the
distribution. See the option --query-swdb of the command
gpgconf for more details. Note, that regardless of this option a
version check can always be triggered using this command:
gpg-connect-agent --dirmngr 'loadswdb --force' /bye
- --keyserver name
- Use name as your keyserver. This is the server that gpg
communicates with to receive keys, send keys, and search for keys. The
format of the name is a URI: `scheme:[//]keyservername[:port]' The
scheme is the type of keyserver: "hkp" for the HTTP (or
compatible) keyservers, "ldap" for the LDAP keyservers, or
"mailto" for the Graff email keyserver. Note that your
particular installation of GnuPG may have other keyserver types available
as well. Keyserver schemes are case-insensitive. After the keyserver name,
optional keyserver configuration options may be provided. These are the
same as the --keyserver-options of gpg, but apply only to
this particular keyserver.
Most keyservers synchronize with each other, so there is generally no need
to send keys to more than one server. The keyserver
hkp://keys.gnupg.net uses round robin DNS to give a different
keyserver each time you use it.
If exactly two keyservers are configured and only one is a Tor hidden
service (.onion), Dirmngr selects the keyserver to use depending on
whether Tor is locally running or not. The check for a running Tor is done
for each new connection.
If no keyserver is explicitly configured, dirmngr will use the built-in
default of hkps://hkps.pool.sks-keyservers.net.
- --nameserver ipaddr
- In ``Tor mode'' Dirmngr uses a public resolver via Tor to resolve DNS
names. If the default public resolver, which is 22.214.171.124, shall not
be used a different one can be given using this option. Note that a
numerical IP address must be given (IPv6 or IPv4) and that no error
checking is done for ipaddr.
- Disable the use of all IPv4 or IPv6 addresses.
- Entirely disables the use of LDAP.
- Entirely disables the use of HTTP.
- When looking for the location of a CRL, the to be tested certificate
usually contains so called CRL Distribution Point (DP) entries which are
URLs describing the way to access the CRL. The first found DP entry is
used. With this option all entries using the HTTP scheme are ignored when
looking for a suitable DP.
- This is similar to --ignore-http-dp but ignores entries using the
LDAP scheme. Both options may be combined resulting in ignoring DPs
- Ignore all OCSP URLs contained in the certificate. The effect is to force
the use of the default responder.
- If the environment variable ‘http_proxy’ has been
set, use its value to access HTTP servers.
- --http-proxy host[:port]
- Use host and port to access HTTP servers. The use of this
option overrides the environment variable ‘
http_proxy’ regardless whether --honor-http-proxy has
- --ldap-proxy host[:port]
- Use host and port to connect to LDAP servers. If port
is omitted, port 389 (standard LDAP port) is used. This overrides any
specified host and port part in a LDAP URL and will also be used if host
and port have been omitted from the URL.
- Never use anything else but the LDAP "proxy" as configured with
--ldap-proxy. Usually dirmngr tries to use other configured
LDAP server if the connection using the "proxy" failed.
- --ldapserverlist-file file
- Read the list of LDAP servers to consult for CRLs and certificates from
file instead of the default per-user ldap server list file. The default
value for file is ‘dirmngr_ldapservers.conf’.
This server list file contains one LDAP server per line in the format
Lines starting with a '#' are comments.
Note that as usual all strings entered are expected to be UTF-8 encoded.
Obviously this will lead to problems if the password has originally been
encoded as Latin-1. There is no other solution here than to put such a
password in the binary encoding into the file (i.e. non-ascii characters
won't show up readable). ([The gpgconf tool might be helpful for
frontends as it enables editing this configuration file using
- --ldaptimeout secs
- Specify the number of seconds to wait for an LDAP query before timing out.
The default is currently 100 seconds. 0 will never timeout.
- This option makes dirmngr add any servers it discovers when validating
certificates against CRLs to the internal list of servers to consult for
certificates and CRLs.
This option is useful when trying to validate a certificate that has a CRL
distribution point that points to a server that is not already listed in
the ldapserverlist. Dirmngr will always go to this server and try to
download the CRL, but chances are high that the certificate used to sign
the CRL is located on the same server. So if dirmngr doesn't add that new
server to list, it will often not be able to verify the signature of the
CRL unless the --add-servers option is used.
Note: The current version of dirmngr has this option disabled by default.
- This option enables OCSP support if requested by the client.
OCSP requests are rejected by default because they may violate the privacy
of the user; for example it is possible to track the time when a user is
reading a mail.
- --ocsp-responder url
- Use url as the default OCSP Responder if the certificate does not
contain information about an assigned responder. Note, that
--ocsp-signer must also be set to a valid certificate.
- --ocsp-signer fpr|file
- Use the certificate with the fingerprint fpr to check the responses
of the default OCSP Responder. Alternatively a filename can be given in
which case the response is expected to be signed by one of the
certificates described in that file. Any argument which contains a slash,
dot or tilde is considered a filename. Usual filename expansion takes
place: A tilde at the start followed by a slash is replaced by the content
of ‘ HOME’, no slash at start describes a relative
filename which will be searched at the home directory. To make sure that
the file is searched in the home directory, either prepend the name
with "./" or use a name which contains a dot.
If a response has been signed by a certificate described by these
fingerprints no further check upon the validity of this certificate is
The format of the FILE is a list of SHA-1 fingerprint, one per line
with optional colons between the bytes. Empty lines and lines prefix with
a hash mark are ignored.
- --ocsp-max-clock-skew n
- The number of seconds a skew between the OCSP responder and them local
clock is accepted. Default is 600 (10 minutes).
- --ocsp-max-period n
- Seconds a response is at maximum considered valid after the time given in
the thisUpdate field. Default is 7776000 (90 days).
- --ocsp-current-period n
- The number of seconds an OCSP response is considered valid after the time
given in the NEXT_UPDATE datum. Default is 10800 (3 hours).
- --max-replies n
- Do not return more that n items in one query. The default is 10.
- --ignore-cert-extension oid
- Add oid to the list of ignored certificate extensions. The
oid is expected to be in dotted decimal form, like 126.96.36.199.
This option may be used more than once. Critical flagged certificate
extensions matching one of the OIDs in the list are treated as if they are
actually handled and thus the certificate won't be rejected due to an
unknown critical extension. Use this option with care because extensions
are usually flagged as critical for a reason.
- --hkp-cacert file
- Use the root certificates in file for verification of the TLS
certificates used with hkps (keyserver access over TLS). If the
file is in PEM format a suffix of .pem is expected for file.
This option may be given multiple times to add more root certificates.
Tilde expansion is supported.
If no hkp-cacert directive is present, dirmngr will make a reasonable
choice: if the keyserver in question is the special pool
hkps.pool.sks-keyservers.net, it will use the bundled root
certificate for that pool. Otherwise, it will use the system CAs.
Here is an example on how to show dirmngr's internal table of OpenPGP keyserver
addresses. The output is intended for debugging purposes and not part of a
gpg-connect-agent --dirmngr 'keyserver --hosttable' /bye
To inhibit the use of a particular host you have noticed in one of the keyserver
pools, you may use
gpg-connect-agent --dirmngr 'keyserver --dead pgpkeys.bnd.de' /bye
The description of the keyserver
command can be printed using
gpg-connect-agent --dirmngr 'help keyserver' /bye
Dirmngr makes use of several directories when running in daemon mode: There are
a few configuration files whih control the operation of dirmngr. By default
they may all be found in the current home directory (see: [option --homedir]).
- This is the standard configuration file read by dirmngr on startup.
It may contain any valid long option; the leading two dashes may not be
entered and the option may not be abbreviated. This file is also read
after a SIGHUP however not all options will actually have an
effect. This default name may be changed on the command line (see: [option
--options]). You should backup this file.
- This directory should be filled with certificates of Root CAs you are
trusting in checking the CRLs and signing OCSP Responses.
Usually these are the same certificates you use with the applications making
use of dirmngr. It is expected that each of these certificate files
contain exactly one DER encoded certificate in a file with the suffix
‘ .crt’ or ‘.der’.
dirmngr reads those certificates on startup and when given a
SIGHUP. Certificates which are not readable or do not make up a proper
X.509 certificate are ignored; see the log file for details.
Applications using dirmngr (e.g. gpgsm) can request these certificates to
complete a trust chain in the same way as with the extra-certs directory
Note that for OCSP responses the certificate specified using the option
--ocsp-signer is always considered valid to sign OCSP requests.
- This directory may contain extra certificates which are preloaded into the
internal cache on startup. Applications using dirmngr (e.g. gpgsm) can
request cached certificates to complete a trust chain. This is convenient
in cases you have a couple intermediate CA certificates or certificates
usually used to sign OCSP responses. These certificates are first tried
before going out to the net to look for them. These certificates must also
be DER encoded and suffixed with ‘ .crt’ or
- This directory is used to store cached CRLs. The
‘crls.d’ part will be created by dirmngr if it does
not exists but you need to make sure that the upper directory exists.
A running dirmngr
may be controlled by signals, i.e. using the
command to send a signal to the process.
Here is a list of supported signals:
- This signal flushes all internally cached CRLs as well as any cached
certificates. Then the certificate cache is reinitialized as on startup.
Options are re-read from the configuration file. Instead of sending this
signal it is better to use
- Shuts down the process but waits until all current requests are fulfilled.
If the process has received 3 of these signals and requests are still
pending, a shutdown is forced. You may also use
instead of this signal
- Shuts down the process immediately.
- This prints some caching statistics to the log file.
The full documentation for this tool is maintained as a Texinfo manual. If GnuPG
and the info program are properly installed at your site, the command
should give you access to the complete manual including a menu structure and an