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diff --git a/doc/dirmngr.texi b/doc/dirmngr.texi new file mode 100644 index 000000000..bb15766b5 --- /dev/null +++ b/doc/dirmngr.texi @@ -0,0 +1,788 @@ +@c Copyright (C) 2002 Klar"alvdalens Datakonsult AB +@c Copyright (C) 2004, 2005, 2006, 2007 g10 Code GmbH +@c This is part of the GnuPG manual. +@c For copying conditions, see the file gnupg.texi. + +@node Invoking DIRMNGR +@chapter Invoking DIRMNGR +@cindex DIRMNGR command options +@cindex command options +@cindex options, DIRMNGR command + +@manpage dirmngr.8 +@ifset manverb +.B dirmngr +\- CRL and OCSP daemon +@end ifset + +@mansect synopsis +@ifset manverb +.B dirmngr +.RI [ options ] +.I command +.RI [ args ] +@end ifset + +@mansect description +Dirmngr is a server for managing and downloading certificate revocation +lists (CRLs) for X.509 certificates and for downloading the certificates +themselves. Dirmngr also handles OCSP requests as an alternative to +CRLs. Dirmngr is either invoked internally by gpgsm or when running as a +system daemon through the @command{dirmngr-client} tool. + +If @command{dirmngr} is started in system daemon mode, it uses a +directory layout as common for system daemons and does not make use of +the default @file{~/.gnupg} directory. + + +@manpause +@noindent +@xref{Option Index},for an index to @command{DIRMNGR}'s commands and +options. +@mancont + +@menu +* Dirmngr Commands:: List of all commands. +* Dirmngr Options:: List of all options. +* Dirmngr Configuration:: Configuration files. +* Dirmngr Signals:: Use of signals. +* Dirmngr Examples:: Some usage examples. +* Dirmngr Protocol:: The protocol dirmngr uses. +@end menu + + +@node Dirmngr Commands +@section Commands +@mansect commands + +Commands are not distinguished from options except for the fact that +only one command is allowed. + +@table @gnupgtabopt +@item --version +@opindex version +Print the program version and licensing information. Note that you cannot +abbreviate this command. + +@item --help, -h +@opindex help +Print a usage message summarizing the most useful command-line options. +Not that you cannot abbreviate this command. + +@item --dump-options +@opindex dump-options +Print a list of all available options and commands. Note that you cannot +abbreviate this command. + +@item --server +@opindex server +Run in server mode and wait for commands on the @code{stdin}. The +default mode is to create a socket and listen for commands there. + +@item --daemon +@opindex 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. + +@item --list-crls +@opindex list-crls +List the contents of the CRL cache on @code{stdout}. This is probably +only useful for debugging purposes. + +@item --load-crl @var{file} +@opindex load-crl +This command requires a filename as additional argument, and it will +make Dirmngr try to import the CRL in @var{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 @code{gpgsm}'s @code{--call-dirmngr loadcrl filename} command +so that @code{gpgsm} can help dirmngr. + +@item --fetch-crl @var{url} +@opindex fetch-crl +This command requires an URL as additional argument, and it will make +dirmngr try to retrieve an import the CRL from that @var{url} into +it's cache. This is mainly useful for debugging purposes. The +@command{dirmngr-client} provides the same feature for a running dirmngr. + +@item --shutdown +@opindex shutdown +This commands shuts down an running instance of Dirmngr. This command +has currently no effect. + +@item --flush +@opindex flush +This command removes all CRLs from Dirmngr's cache. Client requests +will thus trigger reading of fresh CRLs. + +@end table + + +@mansect options +@node Dirmngr Options +@section Option Summary + +@table @gnupgtabopt + +@item --options @var{file} +@opindex options +Reads configuration from @var{file} instead of from the default +per-user configuration file. The default configuration file is named +@file{dirmngr.conf} and expected in the home directory. + +@item --homedir @var{dir} +@opindex options +Set the name of the home directory to @var{dir}. This option is only +effective when used on the command line. The default depends on the +running mode: + +@table @asis + +@item With @code{--daemon} given on the commandline +the directory named @file{/etc/gnupg} for configuration files, +@file{/var/lib/gnupg/} for extra data and @file{/var/cache/gnupg} +for cached CRLs. + +@item Without @code{--daemon} given on the commandline +the directory named @file{.gnupg} directly below the home directory +of the user unless the environment variable @code{GNUPGHOME} has been set +in which case its value will be used. All kind of data is stored below +this directory. +@end table + + +@item -v +@item --verbose +@opindex v +@opindex verbose +Outputs additional information while running. +You can increase the verbosity by giving several +verbose commands to @sc{dirmngr}, such as @option{-vv}. + + +@item --log-file @var{file} +@opindex log-file +Append all logging output to @var{file}. This is very helpful in +seeing what the agent actually does. + +@item --debug-level @var{level} +@opindex debug-level +Select the debug level for investigating problems. @var{level} may be a +numeric value or by a keyword: + +@table @code +@item none +No debugging at all. A value of less than 1 may be used instead of +the keyword. +@item basic +Some basic debug messages. A value between 1 and 2 may be used +instead of the keyword. +@item advanced +More verbose debug messages. A value between 3 and 5 may be used +instead of the keyword. +@item expert +Even more detailed messages. A value between 6 and 8 may be used +instead of the keyword. +@item 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. +@end table + +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. + +@item --debug @var{flags} +@opindex debug +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. + +@item --debug-all +@opindex debug-all +Same as @code{--debug=0xffffffff} + +@item --debug-wait @var{n} +@opindex debug-wait +When running in server mode, wait @var{n} seconds before entering the +actual processing loop and print the pid. This gives time to attach a +debugger. + +@item -s +@itemx --sh +@itemx -c +@itemx --csh +@opindex s +@opindex sh +@opindex c +@opindex 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 @code{SHELL} which is in almost all cases +sufficient. + +@item --force +@opindex force +Enabling this option forces loading of expired CRLs; this is only +useful for debugging. + +@item --disable-ldap +@opindex disable-ldap +Entirely disables the use of LDAP. + +@item --disable-http +@opindex disable-http +Entirely disables the use of HTTP. + +@item --ignore-http-dp +@opindex ignore-http-dp +When looking for the location of a CRL, the to be tested certificate +usually contains so called @dfn{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 @acronym{HTTP} +scheme are ignored when looking for a suitable DP. + +@item --ignore-ldap-dp +@opindex ignore-ldap-dp +This is similar to @option{--ignore-http-dp} but ignores entries using +the @acronym{LDAP} scheme. Both options may be combined resulting in +ignoring DPs entirely. + +@item --ignore-ocsp-service-url +@opindex ignore-ocsp-service-url +Ignore all OCSP URLs contained in the certificate. The effect is to +force the use of the default responder. + +@item --honor-http-proxy +@opindex honor-http-proxy +If the environment variable @env{http_proxy} has been set, use its +value to access HTTP servers. + +@item --http-proxy @var{host}[:@var{port}] +@opindex http-proxy +Use @var{host} and @var{port} to access HTTP servers. The use of this +options overrides the environment variable @env{http_proxy} regardless +whether @option{--honor-http-proxy} has been set. + + +@item --ldap-proxy @var{host}[:@var{port}] +@opindex ldap-proxy +Use @var{host} and @var{port} to connect to LDAP servers. If @var{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. + +@item --only-ldap-proxy +@opindex only-ldap-proxy +Never use anything else but the LDAP "proxy" as configured with +@option{--ldap-proxy}. Usually @command{dirmngr} tries to use other +configured LDAP server if the connection using the "proxy" failed. + + +@item --ldapserverlist-file @var{file} +@opindex ldapserverlist-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 @var{file} is @file{dirmngr_ldapservers.conf} or +@file{ldapservers.conf} when running in @option{--daemon} mode. + +This server list file contains one LDAP server per line in the format + +@sc{hostname:port:username:password:base_dn} + +Lines starting with a @samp{#} 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).@footnote{The @command{gpgconf} tool might be +helpful for frontends as it allows to edit this configuration file using +percent escaped strings.} + + +@item --ldaptimeout @var{secs} +@opindex ldaptimeout +Specify the number of seconds to wait for an LDAP query before timing +out. The default is currently 100 seconds. 0 will never timeout. + + +@item --add-servers +@opindex 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 @code{--add-servers} option is used. + +Note: The current version of dirmngr has this option disabled by default. + + +@item --allow-ocsp +@opindex 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. + + +@item --ocsp-responder @var{url} +@opindex ocsp-responder +Use @var{url} as the default OCSP Responder if the certificate does +not contain information about an assigned responder. Note, that +@code{--ocsp-signer} must also be set to a valid certificate. + +@item --ocsp-signer @var{fpr}|@var{file} +@opindex ocsp-signer +Use the certificate with the fingerprint @var{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 @env{HOME}, no slash at start describes a relative filename +which will be searched at the home directory. To make sure that the +@var{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 @var{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. + + +@item --ocsp-max-clock-skew @var{n} +@opindex ocsp-max-clock-skew +The number of seconds a skew between the OCSP responder and them local +clock is accepted. Default is 600 (20 minutes). + +@item --ocsp-max-period @var{n} +@opindex ocsp-max-period +Seconds a response is at maximum considered valid after the time given +in the thisUpdate field. Default is 7776000 (90 days). + +@item --ocsp-current-period @var{n} +@opindex ocsp-current-period +The number of seconds an OCSP response is considered valid after the +time given in the NEXT_UPDATE datum. Default is 10800 (3 hours). + + +@item --max-replies @var{n} +@opindex max-replies +Do not return more that @var{n} items in one query. The default is +10. + +@item --ignore-cert-extension @var{oid} +@opindex ignore-cert-extension +Add @var{oid} to the list of ignored certificate extensions. The +@var{oid} is expected to be in dotted decimal form, like +@code{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. + +@end table + + +@c +@c Dirmngr Configuration +@c +@mansect files +@node Dirmngr Configuration +@section Configuration + +Dirmngr makes use of several directories when running in daemon mode: + +@table @file + +@item /etc/gnupg +This is where all the configuration files are expected by default. + +@item /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 @acronym{DER} encoded certificate in a file with +the suffix @file{.crt} or @file{.der}. @command{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. + +Note that for OCSP responses the certificate specified using the option +@option{--ocsp-signer} is always considered valid to sign OCSP requests. + + +@item /var/lib/gnupg/extra-certs +This directory may contain extra certificates which are preloaded into +the interal cache on startup. 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 +@acronym{DER} encoded and suffixed with @file{.crt} or @file{.der}. + +@item /var/run/gnupg +This directory keeps the socket file for accsing @command{dirmngr} services. +The name of the socket file will be @file{S.dirmngr}. Make sure that this +directory has the proper permissions to let @command{dirmngr} create the +socket file and that eligible users may read and write to that socket. + +@item /var/cache/gnupg/crls.d +This directory is used to store cached CRLs. The @file{crls.d} part +will be created by dirmngr if it does not exists but you need to make +sure that the upper directory exists. + +@end table +@manpause + +To be able to see what's going on you should create the configure file +@file{/etc/dirmngr/dirmngr.conf} with at least one line: + +@example +log-file /var/log/gnupg/dirmngr.log +@end example + +To be able to perform OCSP requests you probably want to add the line: + +@example +allow-ocsp +@end example + +Now you may start dirmngr as a system daemon using: + +@example +dirmngr --daemon +@end example + +Please ignore the output; it is not needed anymore. Check the log file +to see whether all trusted root certificates have benn loaded correctly. + + +@c +@c Dirmngr Signals +@c +@mansect signals +@node Dirmngr Signals +@section Use of signals. + +A running @command{dirmngr} may be controlled by signals, i.e. using +the @command{kill} command to send a signal to the process. + +Here is a list of supported signals: + +@table @gnupgtabopt + +@item SIGHUP +@cpindex 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. + +@item SIGTERM +@cpindex 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. + +@item SIGINT +@cpindex SIGINT +Shuts down the process immediately. + + +@item SIGUSR1 +@cpindex SIGUSR1 +This prints some caching statistics to the log file. + +@end table + + + +@c +@c Examples +@c +@mansect examples +@node Dirmngr Examples +@section Examples + + +The way to start the dirmngr in the foreground (as done by tools if no +dirmngr is running in the background) is to use: + +@example + dirmngr --server -v +@end example + +If a dirmngr is supposed to be used as a system wide daemon, it should +be started like: + +@example + dirmngr --daemon +@end example + +This will force it to go into the backround, read the default +certificates (including the trusted root certificates) and listen on a +socket for client requests. It does also print information about the +socket used but they are only for compatibilty reasons with old GnuPG +versions and may be ignored. + + +@c +@c Assuan Protocol +@c +@manpause +@node Dirmngr Protocol +@section Dirmngr's Assuan Protocol + +Assuan is the IPC protocol used to access dirmngr. This is a +description of the commands implemented by dirmngr. + +@menu +* Dirmngr LOOKUP:: Look up a certificate via LDAP +* Dirmngr ISVALID:: Validate a certificate using a CRL or OCSP. +* Dirmngr CHECKCRL:: Validate a certificate using a CRL. +* Dirmngr CHECKOCSP:: Validate a certificate using OCSP. +* Dirmngr CACHECERT:: Put a certificate into the internal cache. +* Dirmngr VALIDATE:: Validate a certificate for debugging. +@end menu + +@node Dirmngr LOOKUP +@subsection Return the certificate(s) found + +Lookup certificate. To allow multiple patterns (which are ORed) +quoting is required: Spaces are to be translated into "+" or into +"%20"; obviously this requires that the usual escape quoting rules +are applied. The server responds with: + +@example + S: D <DER encoded certificate> + S: END + S: D <second DER encoded certificate> + S: END + S: OK +@end example + +In this example 2 certificates are returned. The server may return +any number of certificates; OK will also be returned when no +certificates were found. The dirmngr might return a status line + +@example + S: S TRUNCATED <n> +@end example + + +To indicate that the output was truncated to N items due to a +limitation of the server or by an arbitrary set limit. + +The option @option{--url} may be used if instead of a search pattern a +complete URL to the certificate is known: + +@example + C: LOOKUP --url CN%3DWerner%20Koch,o%3DIntevation%20GmbH,c%3DDE?userCertificate +@end example + +If the option @option{--cache-only} is given, no external lookup is done +so that only certificates from the cache are returned. + +With the option @option{--single}, the first and only the first match +will be returned. Unless option @option{--cache-only} is also used, no +local lookup will be done in this case. + + + +@node Dirmngr ISVALID +@subsection Validate a certificate using a CRL or OCSP + +@example + ISVALID [--only-ocsp] [--force-default-responder] @var{certid}|@var{certfpr} +@end example + +Check whether the certificate described by the @var{certid} has been +revoked. Due to caching, the Dirmngr is able to answer immediately in +most cases. + +The @var{certid} is a hex encoded string consisting of two parts, +delimited by a single dot. The first part is the SHA-1 hash of the +issuer name and the second part the serial number. + +Alternatively the certificate's SHA-1 fingerprint @var{certfpr} may be +given in which case an OCSP request is done before consulting the CRL. +If the option @option{--only-ocsp} is given, no fallback to a CRL check +will be used. If the option @option{--force-default-responder} is +given, only the default OCSP responder will be used and any other +methods of obtaining an OCSP responder URL won't be used. + +@noindent +Common return values are: + +@table @code +@item GPG_ERR_NO_ERROR (0) +This is the positive answer: The certificate is not revoked and we have +an up-to-date revocation list for that certificate. If OCSP was used +the responder confirmed that the certificate has not been revoked. + +@item GPG_ERR_CERT_REVOKED +This is the negative answer: The certificate has been revoked. Either +it is in a CRL and that list is up to date or an OCSP responder informed +us that it has been revoked. + +@item GPG_ERR_NO_CRL_KNOWN +No CRL is known for this certificate or the CRL is not valid or out of +date. + +@item GPG_ERR_NO_DATA +The OCSP responder returned an ``unknown'' status. This means that it +is not aware of the certificate's status. + +@item GPG_ERR_NOT_SUPPORTED +This is commonly seen if OCSP support has not been enabled in the +configuration. +@end table + +If DirMngr has not enough information about the given certificate (which +is the case for not yet cached certificates), it will will inquire the +missing data: + +@example + S: INQUIRE SENDCERT <CertID> + C: D <DER encoded certificate> + C: END +@end example + +A client should be aware that DirMngr may ask for more than one +certificate. + +If Dirmngr has a certificate but the signature of the certificate +could not been validated because the root certificate is not known to +dirmngr as trusted, it may ask back to see whether the client trusts +this the root certificate: + +@example + S: INQUIRE ISTRUSTED <CertHexfpr> + C: D 1 + C: END +@end example + +Only this answer will let Dirmngr consider the CRL as valid. + + +@node Dirmngr CHECKCRL +@subsection Validate a certificate using a CRL + +Check whether the certificate with FINGERPRINT (SHA-1 hash of the +entire X.509 certificate blob) is valid or not by consulting the CRL +responsible for this certificate. If the fingerprint has not been +given or the certificate is not know, the function inquires the +certificate using: + +@example + S: INQUIRE TARGETCERT + C: D <DER encoded certificate> + C: END +@end example + +Thus the caller is expected to return the certificate for the request +(which should match FINGERPRINT) as a binary blob. Processing then +takes place without further interaction; in particular dirmngr tries +to locate other required certificate by its own mechanism which +includes a local certificate store as well as a list of trusted root +certificates. + +@noindent +The return code is 0 for success; i.e. the certificate has not been +revoked or one of the usual error codes from libgpg-error. + +@node Dirmngr CHECKOCSP +@subsection Validate a certificate using OCSP + +@example + CHECKOCSP [--force-default-responder] [@var{fingerprint}] +@end example + +Check whether the certificate with @var{fingerprint} (the SHA-1 hash of +the entire X.509 certificate blob) is valid by consulting the appropiate +OCSP responder. If the fingerprint has not been given or the +certificate is not known by Dirmngr, the function inquires the +certificate using: + +@example + S: INQUIRE TARGETCERT + C: D <DER encoded certificate> + C: END +@end example + +Thus the caller is expected to return the certificate for the request +(which should match @var{fingerprint}) as a binary blob. Processing +then takes place without further interaction; in particular dirmngr +tries to locate other required certificates by its own mechanism which +includes a local certificate store as well as a list of trusted root +certificates. + +If the option @option{--force-default-responder} is given, only the +default OCSP responder is used. This option is the per-command variant +of the global option @option{--ignore-ocsp-service-url}. + + +@noindent +The return code is 0 for success; i.e. the certificate has not been +revoked or one of the usual error codes from libgpg-error. + +@node Dirmngr CACHECERT +@subsection Put a certificate into the internal cache + +Put a certificate into the internal cache. This command might be +useful if a client knows in advance certificates required for a test and +wnats to make sure they get added to the internal cache. It is also +helpful for debugging. To get the actual certificate, this command +immediately inquires it using + +@example + S: INQUIRE TARGETCERT + C: D <DER encoded certificate> + C: END +@end example + +Thus the caller is expected to return the certificate for the request +as a binary blob. + +@noindent +The return code is 0 for success; i.e. the certificate has not been +succesfully cached or one of the usual error codes from libgpg-error. + +@node Dirmngr VALIDATE +@subsection Validate a certificate for debugging + +Validate a certificate using the certificate validation function used +internally by dirmngr. This command is only useful for debugging. To +get the actual certificate, this command immediately inquires it using + +@example + S: INQUIRE TARGETCERT + C: D <DER encoded certificate> + C: END +@end example + +Thus the caller is expected to return the certificate for the request +as a binary blob. + + +@mansect see also +@ifset isman +@command{gpgsm}(1), +@command{dirmngr-client}(1) +@end ifset +@include see-also-note.texi + |