Ubuntu Manpage: dirmngr - CRL and OCSP daemon

Provided by: dirmngr_2.1.11-6ubuntu2.1_amd64

NAME

       dirmngr - CRL and OCSP daemon

SYNOPSIS

       dirmngr [options] command [args]

DESCRIPTION

       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, gpgsm, or via the gpg-connect-agent tool.

       For  historical reasons it is also possible to start dirmngr in a system daemon mode which
       uses a different directory layout.  However, this mode is deprecated and may eventually be
       removed.

COMMANDS

Commands are not distinguished from options except for the fact that only one command is
allowed.

--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. Not that
you cannot abbreviate this command.

--dump-options
Print a list of all available options and commands. Note that you cannot
abbreviate this command.

--server
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.

--daemon
Run in background daemon mode and listen for commands on a socket. Note that this
also changes the default home directory and enables the internal certificate
validation code. This mode is deprecated.

--list-crls
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 an 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.

--shutdown
This commands shuts down an running instance of Dirmngr. This command has
currently no effect.

--flush
This command removes all CRLs from Dirmngr's cache. Client requests will thus
trigger reading of fresh CRLs.

OPTIONS

--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 depends on the running mode:

With --daemon given on the commandline
the directory named ‘/etc/gnupg2’ is used for configuration files and
‘/var/cache/gnupg2’ for cached CRLs.

Without --daemon given on the commandline
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. All kind of data is stored below this directory.

-v

--verbose
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.

--debug-level level
Select the debug level for investigating problems. level may be a numeric value or
by a keyword:

none No debugging at all. A value of less than 1 may be used instead of the
keyword.

basic Some basic debug messages. A value between 1 and 2 may be used instead of
the keyword.

advanced
More verbose debug messages. A value between 3 and 5 may be used instead of
the keyword.

expert Even more detailed messages. A value between 6 and 8 may be used instead of
the keyword.

guru 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
This option is only useful for debugging and the behaviour may change at any time
without notice. FLAGS are bit encoded and may be given in usual C-Syntax.

--debug-all
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 debugger.

-s

--sh

-c

--csh Format the info output in daemon mode for use with the standard Bourne shell
respective the C-shell . The default ist to guess it based on the environment
variable SHELL which is in almost all cases sufficient.

--force
Enabling this option forces loading of expired CRLs; this is only useful for
debugging.

--use-tor
This option switches Dirmngr and thus GnuPG into ``Tor mode'' to route all network
access via Tor (an anonymity network). WARNING: As of now this still leaks the DNS
queries; e.g. to lookup the hosts in a keyserver pool. Certain other features are
disabled if this mode is active.

--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.

--nameserver ipaddr
In ``Tor mode'' Dirmngr uses a public resolver via Tor to resolve DNS names. If
the default public resolver, which is 8.8.8.8, 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. DNS queries in Tor
mode do only work if GnuPG as been build with ADNS support.

--disable-ldap
Entirely disables the use of LDAP.

--disable-http
Entirely disables the use of HTTP.

--ignore-http-dp
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.

--ignore-ldap-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-ocsp-service-url
Ignore all OCSP URLs contained in the certificate. The effect is to force the use
of the default responder.

--honor-http-proxy
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 ommitted, 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 ommitted from the URL.

--only-ldap-proxy
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’ or ‘ldapservers.conf’ when running in --daemon mode.

This server list file contains one LDAP server per line in the format

hostname:port:username:password:base_dn

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 orginally 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 allows to edit 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 is currently 100 seconds. 0 will never timeout.

--add-servers
This options 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 options 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.

--allow-ocsp
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. Alternativly a filename can be given in which case the respinse 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 (20 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 2.5.29.3. 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.

EXAMPLES

       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

FILES

Dirmngr makes use of several directories when running in daemon mode:

~/.gnupg

/etc/gnupg
The first is the standard home directory for all configuration files. In the
deprecated system daemon mode the second directory is used instead.

/etc/gnupg/trusted-certs
This directory should be filled with certificates of Root CAs you are trusting in
checking the CRLs and signing OCSP Reponses.

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.

/etc/gnupg/extra-certs
This directory may contain extra certificates which are preloaded into the interal
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 ususally used to sign OCSP
reponses. 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’.

/var/run/gnupg2
This directory is only used in the deprecated system daemon mode. It keeps the
socket file for accessing dirmngr services. The name of the socket file will be
‘S.dirmngr’. Make sure that this directory has the proper permissions to let
dirmngr create the socket file and that eligible users may read and write to that
socket.

~/.gnupg/crls.d

/var/cache/gnupg2/crls.d
The first 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. The second directory is used instead in the deprecated systems
daemon mode.

SIGNALS

       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:

       SIGHUP This signals 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

       SIGTERM
              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
       instead of this signal

       SIGINT Shuts down the process immediately.

       SIGUSR1
              This prints some caching statistics to the log file.