dirmngr (8) - Linux Manuals
dirmngr: CRL and OCSP daemon
dirmngr - CRL and OCSP daemon
SYNOPSISdirmngr [options] command [args]
DESCRIPTIONSince 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, gpgsm, or via the gpg-connect-agent tool.
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 --launch dirmngr.
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 help dirmngr.
- --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 and --homedir 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 -vv.
- --log-file file
Append all logging output to file. This is very helpful in
seeing what the agent actually does. Use 'socket://' to log to
- --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 keyword.
- Some basic debug messages. A value between 1 and 2 may be used instead of the keyword.
- 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
- --tls-debug level
Enable debugging of the TLS layer at level. The details of the
debug level depend on the used TLS library and are not set in stone.
- --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 debugging purposes.
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
Enabling this option forces loading of expired CRLs; this is only
useful for debugging.
The option --use-tor switches Dirmngr and thus GnuPG into
``Tor mode'' to route all network access via Tor (an anonymity
network). Certain other features are disabled in this mode. The
effect of --use-tor cannot be overridden by any other command
or even by reloading dirmngr. The use of --no-use-tor
disables the use of Tor. The default is to use Tor if it is available
on startup or after reloading dirmngr.
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 option is used. Using this together with enabled
Tor mode returns the error ``Not Enabled''.
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
- --connect-timeout n
- --connect-quick-timeout n
Set the timeout for HTTP and generic TCP connection attempts to N
seconds. The value set with the quick variant is used when the
--quick option has been given to certain Assuan commands. The quick
value is capped at the value of the regular connect timeout. The
default values are 15 and 2 seconds. Note that the timeout values are
for each connection attempt; the connection code will attempt to
connect all addresses listed for a server.
- --listen-backlog n
Set the size of the queue for pending connections. The default is 64.
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://keys.openpgp.org.
Note that the above default is a Debian-specific choice. Upstream GnuPG prefers hkps://hkps.pool.sks-keyservers.net. See /usr/share/doc/gpgconf/NEWS.Debian.gz for more details.
Windows users with a keyserver running on their Active Directory should use ldap:/// for name to access this directory.
For accessing anonymous LDAP keyservers name is in general just a ldaps://ldap.example.com. A BaseDN parameter should never be specified. If authentication is required the value of name is for example:
keyserver ldaps://ldap.example.com/????bindname=uid=USERNAME %2Cou=GnuPG%20Users%2Cdc=example%2Cdc=com,password=PASSWORD
Put this all on one line without any spaces and keep the '%2C' as given.
Replace USERNAME, PASSWORD, and the 'dc' parts according to the
instructions received from the LDAP administrator. Note that only
simple authentication (i.e. cleartext passwords) is supported and thus
using ldaps is strongly suggested.
- --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 entirely.
- 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 been set.
- --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 percent-escaped strings.])
- --ldaptimeout secs
- Specify the number of seconds to wait for an LDAP query before timing out. The default are 15 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 done.
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 defined API.
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 (see below).
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 '.der'.
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 kill 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
gpgconf --reload dirmngr
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
gpgconf --kill dirmngr
Shuts down the process immediately.
This prints some caching statistics to the log file.
SEE ALSOgpgsm(1), dirmngr-client(1)
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 index.