1 @c Copyright (C) 2002 Free Software Foundation, Inc.
2 @c This is part of the GnuPG manual.
3 @c For copying conditions, see the file gnupg.texi.
6 @chapter Invoking GPGSM
7 @cindex GPGSM command options
8 @cindex command options
9 @cindex options, GPGSM command
14 \- CMS encryption and signing tool
31 @command{gpgsm} is a tool similar to @command{gpg} to provide digital
32 encryption and signing services on X.509 certificates and the CMS
33 protocol. It is mainly used as a backend for S/MIME mail processing.
34 @command{gpgsm} includes a full featured certificate management and
35 complies with all rules defined for the German Sphinx project.
38 @xref{Option Index}, for an index to @command{GPGSM}'s commands and options.
42 * GPGSM Commands:: List of all commands.
43 * GPGSM Options:: List of all options.
44 * GPGSM Configuration:: Configuration files.
45 * GPGSM Examples:: Some usage examples.
47 Developer information:
48 * Unattended Usage:: Using @command{gpgsm} from other programs.
49 * GPGSM Protocol:: The protocol the server mode uses.
52 @c *******************************************
53 @c *************** ****************
54 @c *************** COMMANDS ****************
55 @c *************** ****************
56 @c *******************************************
61 Commands are not distinguished from options except for the fact that
62 only one command is allowed.
65 * General GPGSM Commands:: Commands not specific to the functionality.
66 * Operational GPGSM Commands:: Commands to select the type of operation.
67 * Certificate Management:: How to manage certificates.
71 @c *******************************************
72 @c ********** GENERAL COMMANDS *************
73 @c *******************************************
74 @node General GPGSM Commands
75 @subsection Commands not specific to the function
80 Print the program version and licensing information. Note that you
81 cannot abbreviate this command.
85 Print a usage message summarizing the most useful command-line options.
86 Note that you cannot abbreviate this command.
90 Print warranty information. Note that you cannot abbreviate this
95 Print a list of all available options and commands. Note that you cannot
96 abbreviate this command.
100 @c *******************************************
101 @c ******** OPERATIONAL COMMANDS ***********
102 @c *******************************************
103 @node Operational GPGSM Commands
104 @subsection Commands to select the type of operation
109 Perform an encryption. The keys the data is encrypted too must be set
110 using the option @option{--recipient}.
114 Perform a decryption; the type of input is automatically determined. It
115 may either be in binary form or PEM encoded; automatic determination of
116 base-64 encoding is not done.
120 Create a digital signature. The key used is either the fist one found
121 in the keybox or those set with the @option{--local-user} option.
125 Check a signature file for validity. Depending on the arguments a
126 detached signature may also be checked.
130 Run in server mode and wait for commands on the @code{stdin}.
132 @item --call-dirmngr @var{command} [@var{args}]
133 @opindex call-dirmngr
134 Behave as a Dirmngr client issuing the request @var{command} with the
135 optional list of @var{args}. The output of the Dirmngr is printed
136 stdout. Please note that file names given as arguments should have an
137 absolute file name (i.e. commencing with @code{/} because they are
138 passed verbatim to the Dirmngr and the working directory of the
139 Dirmngr might not be the same as the one of this client. Currently it
140 is not possible to pass data via stdin to the Dirmngr. @var{command}
141 should not contain spaces.
143 This is command is required for certain maintaining tasks of the dirmngr
144 where a dirmngr must be able to call back to @command{gpgsm}. See the Dirmngr
147 @item --call-protect-tool @var{arguments}
148 @opindex call-protect-tool
149 Certain maintenance operations are done by an external program call
150 @command{gpg-protect-tool}; this is usually not installed in a directory
151 listed in the PATH variable. This command provides a simple wrapper to
152 access this tool. @var{arguments} are passed verbatim to this command;
153 use @samp{--help} to get a list of supported operations.
159 @c *******************************************
160 @c ******* CERTIFICATE MANAGEMENT **********
161 @c *******************************************
162 @node Certificate Management
163 @subsection How to manage the certificates and keys
169 -This command allows the creation of a certificate signing request. It
170 -is commonly used along with the @option{--output} option to save the
171 -created CSR into a file. If used with the @option{--batch} a parameter
172 -file is used to create the CSR.
175 This command allows the creation of a certificate signing request or a
176 self-signed certificate. It is commonly used along with the
177 @option{--output} option to save the created CSR or certificate into a
178 file. If used with the @option{--batch} a parameter file is used to
179 create the CSR or certificate and it is further possible to create
180 non-self-signed certificates.
186 List all available certificates stored in the local key database.
187 Note that the displayed data might be reformatted for better human
188 readability and illegal characters are replaced by safe substitutes.
190 @item --list-secret-keys
192 @opindex list-secret-keys
193 List all available certificates for which a corresponding a secret key
196 @item --list-external-keys @var{pattern}
198 List certificates matching @var{pattern} using an external server. This
199 utilizes the @code{dirmngr} service.
203 Same as @option{--list-keys} but also prints all keys making up the chain.
210 List all available certificates stored in the local key database using a
211 format useful mainly for debugging.
215 Same as @option{--dump-keys} but also prints all keys making up the chain.
217 @item --dump-secret-keys
218 @opindex dump-secret-keys
219 List all available certificates for which a corresponding a secret key
220 is available using a format useful mainly for debugging.
222 @item --dump-external-keys @var{pattern}
223 @opindex dump-external-keys
224 List certificates matching @var{pattern} using an external server.
225 This utilizes the @code{dirmngr} service. It uses a format useful
226 mainly for debugging.
228 @item --keydb-clear-some-cert-flags
229 @opindex keydb-clear-some-cert-flags
230 This is a debugging aid to reset certain flags in the key database
231 which are used to cache certain certificate stati. It is especially
232 useful if a bad CRL or a weird running OCSP responder did accidentally
233 revoke certificate. There is no security issue with this command
234 because @command{gpgsm} always make sure that the validity of a certificate is
235 checked right before it is used.
237 @item --delete-keys @var{pattern}
239 Delete the keys matching @var{pattern}. Note that there is no command
240 to delete the secret part of the key directly. In case you need to do
241 this, you should run the command @code{gpgsm --dump-secret-keys KEYID}
242 before you delete the key, copy the string of hex-digits in the
243 ``keygrip'' line and delete the file consisting of these hex-digits
244 and the suffix @code{.key} from the @file{private-keys-v1.d} directory
245 below our GnuPG home directory (usually @file{~/.gnupg}).
247 @item --export [@var{pattern}]
249 Export all certificates stored in the Keybox or those specified by the
250 optional @var{pattern}. Those pattern consist of a list of user ids
251 (@pxref{how-to-specify-a-user-id}). When used along with the
252 @option{--armor} option a few informational lines are prepended before
253 each block. There is one limitation: As there is no commonly agreed
254 upon way to pack more than one certificate into an ASN.1 structure,
255 the binary export (i.e. without using @option{armor}) works only for
256 the export of one certificate. Thus it is required to specify a
257 @var{pattern} which yields exactly one certificate. Ephemeral
258 certificate are only exported if all @var{pattern} are given as
259 fingerprints or keygrips.
261 @item --export-secret-key-p12 @var{key-id}
263 Export the private key and the certificate identified by @var{key-id} in
264 a PKCS#12 format. When using along with the @code{--armor} option a few
265 informational lines are prepended to the output. Note, that the PKCS#12
266 format is not very secure and this command is only provided if there is
267 no other way to exchange the private key. (@pxref{option --p12-charset})
269 @item --import [@var{files}]
271 Import the certificates from the PEM or binary encoded files as well as
272 from signed-only messages. This command may also be used to import a
273 secret key from a PKCS#12 file.
277 Read information about the private keys from the smartcard and import
278 the certificates from there. This command utilizes the @command{gpg-agent}
279 and in turn the @command{scdaemon}.
281 @item --passwd @var{user_id}
283 Change the passphrase of the private key belonging to the certificate
284 specified as @var{user_id}. Note, that changing the passphrase/PIN of a
285 smartcard is not yet supported.
290 @c *******************************************
291 @c *************** ****************
292 @c *************** OPTIONS ****************
293 @c *************** ****************
294 @c *******************************************
297 @section Option Summary
299 @command{GPGSM} features a bunch of options to control the exact behaviour
300 and to change the default configuration.
303 * Configuration Options:: How to change the configuration.
304 * Certificate Options:: Certificate related options.
305 * Input and Output:: Input and Output.
306 * CMS Options:: How to change how the CMS is created.
307 * Esoteric Options:: Doing things one usually do not want to do.
311 @c *******************************************
312 @c ******** CONFIGURATION OPTIONS **********
313 @c *******************************************
314 @node Configuration Options
315 @subsection How to change the configuration
317 These options are used to change the configuration and are usually found
322 @item --options @var{file}
324 Reads configuration from @var{file} instead of from the default
325 per-user configuration file. The default configuration file is named
326 @file{gpgsm.conf} and expected in the @file{.gnupg} directory directly
327 below the home directory of the user.
329 @include opt-homedir.texi
336 Outputs additional information while running.
337 You can increase the verbosity by giving several
338 verbose commands to @command{gpgsm}, such as @samp{-vv}.
340 @item --policy-file @var{filename}
342 Change the default name of the policy file to @var{filename}.
344 @item --agent-program @var{file}
345 @opindex agent-program
346 Specify an agent program to be used for secret key operations. The
347 default value is the @file{/usr/local/bin/gpg-agent}. This is only used
348 as a fallback when the environment variable @code{GPG_AGENT_INFO} is not
349 set or a running agent cannot be connected.
351 @item --dirmngr-program @var{file}
352 @opindex dirmnr-program
353 Specify a dirmngr program to be used for @acronym{CRL} checks. The
354 default value is @file{/usr/sbin/dirmngr}. This is only used as a
355 fallback when the environment variable @code{DIRMNGR_INFO} is not set or
356 a running dirmngr cannot be connected.
358 @item --prefer-system-dirmngr
359 @opindex prefer-system-dirmngr
360 If a system wide @command{dirmngr} is running in daemon mode, first try
361 to connect to this one. Fallback to a pipe based server if this does
362 not work. Under Windows this option is ignored because the system dirmngr is
365 @item --disable-dirmngr
366 Entirely disable the use of the Dirmngr.
368 @item --no-secmem-warning
369 @opindex no-secmem-warning
370 Do not print a warning when the so called "secure memory" cannot be used.
372 @item --log-file @var{file}
374 When running in server mode, append all logging output to @var{file}.
379 @c *******************************************
380 @c ******** CERTIFICATE OPTIONS ************
381 @c *******************************************
382 @node Certificate Options
383 @subsection Certificate related options
387 @item --enable-policy-checks
388 @itemx --disable-policy-checks
389 @opindex enable-policy-checks
390 @opindex disable-policy-checks
391 By default policy checks are enabled. These options may be used to
394 @item --enable-crl-checks
395 @itemx --disable-crl-checks
396 @opindex enable-crl-checks
397 @opindex disable-crl-checks
398 By default the @acronym{CRL} checks are enabled and the DirMngr is used
399 to check for revoked certificates. The disable option is most useful
400 with an off-line network connection to suppress this check.
402 @item --enable-trusted-cert-crl-check
403 @itemx --disable-trusted-cert-crl-check
404 @opindex enable-trusted-cert-crl-check
405 @opindex disable-trusted-cert-crl-check
406 By default the @acronym{CRL} for trusted root certificates are checked
407 like for any other certificates. This allows a CA to revoke its own
408 certificates voluntary without the need of putting all ever issued
409 certificates into a CRL. The disable option may be used to switch this
410 extra check off. Due to the caching done by the Dirmngr, there will not be
411 any noticeable performance gain. Note, that this also disables possible
412 OCSP checks for trusted root certificates. A more specific way of
413 disabling this check is by adding the ``relax'' keyword to the root CA
414 line of the @file{trustlist.txt}
417 @item --force-crl-refresh
418 @opindex force-crl-refresh
419 Tell the dirmngr to reload the CRL for each request. For better
420 performance, the dirmngr will actually optimize this by suppressing
421 the loading for short time intervals (e.g. 30 minutes). This option
422 is useful to make sure that a fresh CRL is available for certificates
423 hold in the keybox. The suggested way of doing this is by using it
424 along with the option @option{--with-validation} for a key listing
425 command. This option should not be used in a configuration file.
428 @itemx --disable-ocsp
430 @opindex disable-ocsp
431 By default @acronym{OCSP} checks are disabled. The enable option may
432 be used to enable OCSP checks via Dirmngr. If @acronym{CRL} checks
433 are also enabled, CRLs will be used as a fallback if for some reason an
434 OCSP request will not succeed. Note, that you have to allow OCSP
435 requests in Dirmngr's configuration too (option
436 @option{--allow-ocsp}) and configure Dirmngr properly. If you do not do
437 so you will get the error code @samp{Not supported}.
439 @item --auto-issuer-key-retrieve
440 @opindex auto-issuer-key-retrieve
441 If a required certificate is missing while validating the chain of
442 certificates, try to load that certificate from an external location.
443 This usually means that Dirmngr is employed to search for the
444 certificate. Note that this option makes a "web bug" like behavior
445 possible. LDAP server operators can see which keys you request, so by
446 sending you a message signed by a brand new key (which you naturally
447 will not have on your local keybox), the operator can tell both your IP
448 address and the time when you verified the signature.
451 @item --validation-model @var{name}
452 @opindex validation-model
453 This option changes the default validation model. The only possible
454 values are "shell" (which is the default), "chain" which forces the
455 use of the chain model and "steed" for a new simplified model. The
456 chain model is also used if an option in the @file{trustlist.txt} or
457 an attribute of the certificate requests it. However the standard
458 model (shell) is in that case always tried first.
460 @item --ignore-cert-extension @var{oid}
461 @opindex ignore-cert-extension
462 Add @var{oid} to the list of ignored certificate extensions. The
463 @var{oid} is expected to be in dotted decimal form, like
464 @code{2.5.29.3}. This option may be used more than once. Critical
465 flagged certificate extensions matching one of the OIDs in the list
466 are treated as if they are actually handled and thus the certificate
467 will not be rejected due to an unknown critical extension. Use this
468 option with care because extensions are usually flagged as critical
473 @c *******************************************
474 @c *********** INPUT AND OUTPUT ************
475 @c *******************************************
476 @node Input and Output
477 @subsection Input and Output
483 Create PEM encoded output. Default is binary output.
487 Create Base-64 encoded output; i.e. PEM without the header lines.
490 @opindex assume-armor
491 Assume the input data is PEM encoded. Default is to autodetect the
492 encoding but this is may fail.
494 @item --assume-base64
495 @opindex assume-base64
496 Assume the input data is plain base-64 encoded.
498 @item --assume-binary
499 @opindex assume-binary
500 Assume the input data is binary encoded.
502 @anchor{option --p12-charset}
503 @item --p12-charset @var{name}
505 @command{gpgsm} uses the UTF-8 encoding when encoding passphrases for
506 PKCS#12 files. This option may be used to force the passphrase to be
507 encoded in the specified encoding @var{name}. This is useful if the
508 application used to import the key uses a different encoding and thus
509 will not be able to import a file generated by @command{gpgsm}. Commonly
510 used values for @var{name} are @code{Latin1} and @code{CP850}. Note
511 that @command{gpgsm} itself automagically imports any file with a
512 passphrase encoded to the most commonly used encodings.
515 @item --default-key @var{user_id}
517 Use @var{user_id} as the standard key for signing. This key is used if
518 no other key has been defined as a signing key. Note, that the first
519 @option{--local-users} option also sets this key if it has not yet been
520 set; however @option{--default-key} always overrides this.
523 @item --local-user @var{user_id}
524 @item -u @var{user_id}
526 Set the user(s) to be used for signing. The default is the first
527 secret key found in the database.
530 @item --recipient @var{name}
533 Encrypt to the user id @var{name}. There are several ways a user id
534 may be given (@pxref{how-to-specify-a-user-id}).
537 @item --output @var{file}
540 Write output to @var{file}. The default is to write it to stdout.
543 @item --with-key-data
544 @opindex with-key-data
545 Displays extra information with the @code{--list-keys} commands. Especially
546 a line tagged @code{grp} is printed which tells you the keygrip of a
547 key. This string is for example used as the file name of the
550 @item --with-validation
551 @opindex with-validation
552 When doing a key listing, do a full validation check for each key and
553 print the result. This is usually a slow operation because it
554 requires a CRL lookup and other operations.
556 When used along with --import, a validation of the certificate to
557 import is done and only imported if it succeeds the test. Note that
558 this does not affect an already available certificate in the DB.
559 This option is therefore useful to simply verify a certificate.
562 @item --with-md5-fingerprint
563 For standard key listings, also print the MD5 fingerprint of the
567 Include the keygrip in standard key listings. Note that the keygrip is
568 always listed in --with-colons mode.
572 @c *******************************************
573 @c ************* CMS OPTIONS ***************
574 @c *******************************************
576 @subsection How to change how the CMS is created.
579 @item --include-certs @var{n}
580 @opindex include-certs
581 Using @var{n} of -2 includes all certificate except for the root cert,
582 -1 includes all certs, 0 does not include any certs, 1 includes only the
583 signers cert and all other positive values include up to @var{n}
584 certificates starting with the signer cert. The default is -2.
586 @item --cipher-algo @var{oid}
588 Use the cipher algorithm with the ASN.1 object identifier @var{oid} for
589 encryption. For convenience the strings @code{3DES}, @code{AES} and
590 @code{AES256} may be used instead of their OIDs. The default is
591 @code{3DES} (1.2.840.113549.3.7).
593 @item --digest-algo @code{name}
594 Use @code{name} as the message digest algorithm. Usually this
595 algorithm is deduced from the respective signing certificate. This
596 option forces the use of the given algorithm and may lead to severe
597 interoperability problems.
603 @c *******************************************
604 @c ******** ESOTERIC OPTIONS ***************
605 @c *******************************************
606 @node Esoteric Options
607 @subsection Doing things one usually do not want to do.
612 @item --extra-digest-algo @var{name}
613 @opindex extra-digest-algo
614 Sometimes signatures are broken in that they announce a different digest
615 algorithm than actually used. @command{gpgsm} uses a one-pass data
616 processing model and thus needs to rely on the announced digest
617 algorithms to properly hash the data. As a workaround this option may
618 be used to tell gpg to also hash the data using the algorithm
619 @var{name}; this slows processing down a little bit but allows to verify
620 such broken signatures. If @command{gpgsm} prints an error like
621 ``digest algo 8 has not been enabled'' you may want to try this option,
622 with @samp{SHA256} for @var{name}.
625 @item --faked-system-time @var{epoch}
626 @opindex faked-system-time
627 This option is only useful for testing; it sets the system time back or
628 forth to @var{epoch} which is the number of seconds elapsed since the year
629 1970. Alternatively @var{epoch} may be given as a full ISO time string
630 (e.g. "20070924T154812").
632 @item --with-ephemeral-keys
633 @opindex with-ephemeral-keys
634 Include ephemeral flagged keys in the output of key listings. Note
635 that they are included anyway if the key specification for a listing
636 is given as fingerprint or keygrip.
638 @item --debug-level @var{level}
640 Select the debug level for investigating problems. @var{level} may be
641 a numeric value or by a keyword:
645 No debugging at all. A value of less than 1 may be used instead of
648 Some basic debug messages. A value between 1 and 2 may be used
649 instead of the keyword.
651 More verbose debug messages. A value between 3 and 5 may be used
652 instead of the keyword.
654 Even more detailed messages. A value between 6 and 8 may be used
655 instead of the keyword.
657 All of the debug messages you can get. A value greater than 8 may be
658 used instead of the keyword. The creation of hash tracing files is
659 only enabled if the keyword is used.
662 How these messages are mapped to the actual debugging flags is not
663 specified and may change with newer releases of this program. They are
664 however carefully selected to best aid in debugging.
666 @item --debug @var{flags}
668 This option is only useful for debugging and the behaviour may change
669 at any time without notice; using @code{--debug-levels} is the
670 preferred method to select the debug verbosity. FLAGS are bit encoded
671 and may be given in usual C-Syntax. The currently defined bits are:
675 X.509 or OpenPGP protocol related data
677 values of big number integers
679 low level crypto operations
685 show memory statistics.
687 write hashed data to files named @code{dbgmd-000*}
689 trace Assuan protocol
692 Note, that all flags set using this option may get overridden by
693 @code{--debug-level}.
697 Same as @code{--debug=0xffffffff}
699 @item --debug-allow-core-dump
700 @opindex debug-allow-core-dump
701 Usually @command{gpgsm} tries to avoid dumping core by well written code and by
702 disabling core dumps for security reasons. However, bugs are pretty
703 durable beasts and to squash them it is sometimes useful to have a core
704 dump. This option enables core dumps unless the Bad Thing happened
705 before the option parsing.
707 @item --debug-no-chain-validation
708 @opindex debug-no-chain-validation
709 This is actually not a debugging option but only useful as such. It
710 lets @command{gpgsm} bypass all certificate chain validation checks.
712 @item --debug-ignore-expiration
713 @opindex debug-ignore-expiration
714 This is actually not a debugging option but only useful as such. It
715 lets @command{gpgsm} ignore all notAfter dates, this is used by the regression
718 @item --fixed-passphrase @var{string}
719 @opindex fixed-passphrase
720 Supply the passphrase @var{string} to the gpg-protect-tool. This
721 option is only useful for the regression tests included with this
722 package and may be revised or removed at any time without notice.
724 @item --no-common-certs-import
725 @opindex no-common-certs-import
726 Suppress the import of common certificates on keybox creation.
730 All the long options may also be given in the configuration file after
731 stripping off the two leading dashes.
733 @c *******************************************
734 @c *************** ****************
735 @c *************** USER ID ****************
736 @c *************** ****************
737 @c *******************************************
738 @mansect how to specify a user id
740 @include specify-user-id.texi
743 @c *******************************************
744 @c *************** ****************
745 @c *************** FILES ****************
746 @c *************** ****************
747 @c *******************************************
749 @node GPGSM Configuration
750 @section Configuration files
752 There are a few configuration files to control certain aspects of
753 @command{gpgsm}'s operation. Unless noted, they are expected in the
754 current home directory (@pxref{option --homedir}).
760 This is the standard configuration file read by @command{gpgsm} on
761 startup. It may contain any valid long option; the leading two dashes
762 may not be entered and the option may not be abbreviated. This default
763 name may be changed on the command line (@pxref{option
764 --options}). You should backup this file.
769 This is a list of allowed CA policies. This file should list the
770 object identifiers of the policies line by line. Empty lines and
771 lines starting with a hash mark are ignored. Policies missing in this
772 file and not marked as critical in the certificate will print only a
773 warning; certificates with policies marked as critical and not listed
774 in this file will fail the signature verification. You should backup
777 For example, to allow only the policy 2.289.9.9, the file should look
788 @cindex qualified.txt
789 This is the list of root certificates used for qualified certificates.
790 They are defined as certificates capable of creating legally binding
791 signatures in the same way as handwritten signatures are. Comments
792 start with a hash mark and empty lines are ignored. Lines do have a
793 length limit but this is not a serious limitation as the format of the
794 entries is fixed and checked by gpgsm: A non-comment line starts with
795 optional whitespace, followed by exactly 40 hex character, white space
796 and a lowercased 2 letter country code. Additional data delimited with
797 by a white space is current ignored but might late be used for other
800 Note that even if a certificate is listed in this file, this does not
801 mean that the certificate is trusted; in general the certificates listed
802 in this file need to be listed also in @file{trustlist.txt}.
804 This is a global file an installed in the data directory
805 (e.g. @file{/usr/share/gnupg/qualified.txt}). GnuPG installs a suitable
806 file with root certificates as used in Germany. As new Root-CA
807 certificates may be issued over time, these entries may need to be
808 updated; new distributions of this software should come with an updated
809 list but it is still the responsibility of the Administrator to check
810 that this list is correct.
812 Everytime @command{gpgsm} uses a certificate for signing or verification
813 this file will be consulted to check whether the certificate under
814 question has ultimately been issued by one of these CAs. If this is the
815 case the user will be informed that the verified signature represents a
816 legally binding (``qualified'') signature. When creating a signature
817 using such a certificate an extra prompt will be issued to let the user
818 confirm that such a legally binding signature shall really be created.
820 Because this software has not yet been approved for use with such
821 certificates, appropriate notices will be shown to indicate this fact.
825 This is plain text file with a few help entries used with
826 @command{pinentry} as well as a large list of help items for
827 @command{gpg} and @command{gpgsm}. The standard file has English help
828 texts; to install localized versions use filenames like @file{help.LL.txt}
829 with LL denoting the locale. GnuPG comes with a set of predefined help
830 files in the data directory (e.g. @file{/usr/share/gnupg/help.de.txt})
831 and allows overriding of any help item by help files stored in the
832 system configuration directory (e.g. @file{/etc/gnupg/help.de.txt}).
833 For a reference of the help file's syntax, please see the installed
834 @file{help.txt} file.
838 @cindex com-certs.pem
839 This file is a collection of common certificates used to populated a
840 newly created @file{pubring.kbx}. An administrator may replace this
841 file with a custom one. The format is a concatenation of PEM encoded
842 X.509 certificates. This global file is installed in the data directory
843 (e.g. @file{/usr/share/gnupg/com-certs.pem}).
848 Note that on larger installations, it is useful to put predefined files
849 into the directory @file{/etc/skel/.gnupg/} so that newly created users
850 start up with a working configuration. For existing users a small
851 helper script is provided to create these files (@pxref{addgnupghome}).
853 For internal purposes gpgsm creates and maintains a few other files;
854 they all live in in the current home directory (@pxref{option
855 --homedir}). Only @command{gpgsm} may modify these files.
861 This a database file storing the certificates as well as meta
862 information. For debugging purposes the tool @command{kbxutil} may be
863 used to show the internal structure of this file. You should backup
868 This content of this file is used to maintain the internal state of the
869 random number generator across invocations. The same file is used by
870 other programs of this software too.
874 If this file exists and the environment variable @env{GPG_AGENT_INFO} is
875 not set, @command{gpgsm} will first try to connect to this socket for
876 accessing @command{gpg-agent} before starting a new @command{gpg-agent}
877 instance. Under Windows this socket (which in reality be a plain file
878 describing a regular TCP listening port) is the standard way of
879 connecting the @command{gpg-agent}.
884 @c *******************************************
885 @c *************** ****************
886 @c *************** EXAMPLES ****************
887 @c *************** ****************
888 @c *******************************************
894 $ gpgsm -er goo@@bar.net <plaintext >ciphertext
898 @c *******************************************
899 @c *************** **************
900 @c *************** UNATTENDED **************
901 @c *************** **************
902 @c *******************************************
904 @node Unattended Usage
905 @section Unattended Usage
907 @command{gpgsm} is often used as a backend engine by other software. To help
908 with this a machine interface has been defined to have an unambiguous
909 way to do this. This is most likely used with the @code{--server} command
910 but may also be used in the standard operation mode by using the
911 @code{--status-fd} option.
914 * Automated signature checking:: Automated signature checking.
915 * CSR and certificate creation:: CSR and certificate creation.
918 @node Automated signature checking,,,Unattended Usage
919 @section Automated signature checking
921 It is very important to understand the semantics used with signature
922 verification. Checking a signature is not as simple as it may sound and
923 so the operation is a bit complicated. In most cases it is required
924 to look at several status lines. Here is a table of all cases a signed
928 @item The signature is valid
929 This does mean that the signature has been successfully verified, the
930 certificates are all sane. However there are two subcases with
931 important information: One of the certificates may have expired or a
932 signature of a message itself as expired. It is a sound practise to
933 consider such a signature still as valid but additional information
934 should be displayed. Depending on the subcase @command{gpgsm} will issue
937 @item signature valid and nothing did expire
938 @code{GOODSIG}, @code{VALIDSIG}, @code{TRUST_FULLY}
939 @item signature valid but at least one certificate has expired
940 @code{EXPKEYSIG}, @code{VALIDSIG}, @code{TRUST_FULLY}
941 @item signature valid but expired
942 @code{EXPSIG}, @code{VALIDSIG}, @code{TRUST_FULLY}
943 Note, that this case is currently not implemented.
946 @item The signature is invalid
947 This means that the signature verification failed (this is an indication
948 of af a transfer error, a program error or tampering with the message).
949 @command{gpgsm} issues one of these status codes sequences:
952 @item @code{GOODSIG}, @code{VALIDSIG} @code{TRUST_NEVER}
955 @item Error verifying a signature
956 For some reason the signature could not be verified, i.e. it cannot be
957 decided whether the signature is valid or invalid. A common reason for
958 this is a missing certificate.
962 @node CSR and certificate creation,,,Unattended Usage
963 @section CSR and certificate creation
966 @strong{Please notice}: The immediate creation of certificates is only
967 supported by GnuPG version 2.1 or later. With a 2.0 version you may
971 The command @option{--gen-key} may be used along with the option
972 @option{--batch} to either create a certificate signing request (CSR)
973 or an X.509 certificate. The is controlled by a parameter file; the
974 format of this file is as follows:
977 @item Text only, line length is limited to about 1000 characters.
978 @item UTF-8 encoding must be used to specify non-ASCII characters.
979 @item Empty lines are ignored.
980 @item Leading and trailing while space is ignored.
981 @item A hash sign as the first non white space character indicates
983 @item Control statements are indicated by a leading percent sign, the
984 arguments are separated by white space from the keyword.
985 @item Parameters are specified by a keyword, followed by a colon. Arguments
986 are separated by white space.
987 @item The first parameter must be @samp{Key-Type}, control statements
988 may be placed anywhere.
990 The order of the parameters does not matter except for @samp{Key-Type}
991 which must be the first parameter. The parameters are only used for
992 the generated CSR/certificate; parameters from previous sets are not
993 used. Some syntactically checks may be performed.
995 Key generation takes place when either the end of the parameter file
996 is reached, the next @samp{Key-Type} parameter is encountered or at the
997 control statement @samp{%commit} is encountered.
1005 @item %echo @var{text}
1006 Print @var{text} as diagnostic.
1009 Suppress actual key generation (useful for syntax checking).
1012 Perform the key generation. Note that an implicit commit is done at
1013 the next @asis{Key-Type} parameter.
1015 @c %certfile <filename>
1016 @c [Not yet implemented!]
1017 @c Do not write the certificate to the keyDB but to <filename>.
1018 @c This must be given before the first
1019 @c commit to take place, duplicate specification of the same filename
1020 @c is ignored, the last filename before a commit is used.
1021 @c The filename is used until a new filename is used (at commit points)
1022 @c and all keys are written to that file. If a new filename is given,
1023 @c this file is created (and overwrites an existing one).
1024 @c Both control statements must be given.
1032 @item Key-Type: @var{algo}
1033 Starts a new parameter block by giving the type of the primary
1034 key. The algorithm must be capable of signing. This is a required
1035 parameter. The only supported value for @var{algo} is @samp{rsa}.
1037 @item Key-Length: @var{nbits}
1038 The requested length of a generated key in bits. Defaults to 2048.
1040 @item Key-Grip: @var{hexstring}
1041 This is optional and used to generate a CSR or certificatet for an
1042 already existing key. Key-Length will be ignored when given.
1044 @item Key-Usage: @var{usage-list}
1045 Space or comma delimited list of key usage, allowed values are
1046 @samp{encrypt}, @samp{sign} and @samp{cert}. This is used to generate
1047 the keyUsage extension. Please make sure that the algorithm is
1048 capable of this usage. Default is to allow encrypt and sign.
1050 @item Name-DN: @var{subject-name}
1051 This is the Distinguished Name (DN) of the subject in RFC-2253 format.
1053 @item Name-Email: @var{string}
1054 This is an email address for the altSubjectName. This parameter is
1055 optional but may occur several times to add several email addresses to
1058 @item Name-DNS: @var{string}
1059 The is an DNS name for the altSubjectName. This parameter is optional
1060 but may occur several times to add several DNS names to a certificate.
1062 @item Name-URI: @var{string}
1063 This is an URI for the altSubjectName. This parameter is optional but
1064 may occur several times to add several URIs to a certificate.
1068 Additional parameters used to create a certificate (in contrast to a
1069 certificate signing request):
1073 @item Serial: @var{sn}
1074 If this parameter is given an X.509 certificate will be generated.
1075 @var{sn} is expected to be a hex string representing an unsigned
1076 integer of arbitary length. The special value @samp{random} can be
1077 used to create a 64 bit random serial number.
1079 @item Issuer-DN: @var{issuer-name}
1080 This is the DN name of the issuer in rfc2253 format. If it is not set
1081 it will default to the subject DN and a special GnuPG extension will
1082 be included in the certificate to mark it as a standalone certificate.
1084 @item Creation-Date: @var{iso-date}
1085 @itemx Not-Before: @var{iso-date}
1086 Set the notBefore date of the certificate. Either a date like
1087 @samp{1986-04-26} or @samp{1986-04-26 12:00} or a standard ISO
1088 timestamp like @samp{19860426T042640} may be used. The time is
1089 considered to be UTC. If it is not given the current date is used.
1091 @item Expire-Date: @var{iso-date}
1092 @itemx Not-After: @var{iso-date}
1093 Set the notAfter date of the certificate. Either a date like
1094 @samp{2063-04-05} or @samp{2063-04-05 17:00} or a standard ISO
1095 timestamp like @samp{20630405T170000} may be used. The time is
1096 considered to be UTC. If it is not given a default value in the not
1097 too far future is used.
1099 @item Signing-Key: @var{keygrip}
1100 This gives the keygrip of the key used to sign the certificate. If it
1101 is not given a self-signed certificate will be created. For
1102 compatibility with future versions, it is suggested to prefix the
1103 keygrip with a @samp{&}.
1105 @item Hash-Algo: @var{hash-algo}
1106 Use @var{hash-algo} for this CSR or certificate. The supported hash
1107 algorithms are: @samp{sha1}, @samp{sha256}, @samp{sha384} and
1108 @samp{sha512}; they may also be specified with uppercase letters. The
1109 default is @samp{sha1}.
1113 @c *******************************************
1114 @c *************** *****************
1115 @c *************** ASSSUAN *****************
1116 @c *************** *****************
1117 @c *******************************************
1118 @node GPGSM Protocol
1119 @section The Protocol the Server Mode Uses.
1121 Description of the protocol used to access @command{GPGSM}.
1122 @command{GPGSM} does implement the Assuan protocol and in addition
1123 provides a regular command line interface which exhibits a full client
1124 to this protocol (but uses internal linking). To start
1125 @command{gpgsm} as a server the command line the option
1126 @code{--server} must be used. Additional options are provided to
1127 select the communication method (i.e. the name of the socket).
1129 We assume that the connection has already been established; see the
1130 Assuan manual for details.
1133 * GPGSM ENCRYPT:: Encrypting a message.
1134 * GPGSM DECRYPT:: Decrypting a message.
1135 * GPGSM SIGN:: Signing a message.
1136 * GPGSM VERIFY:: Verifying a message.
1137 * GPGSM GENKEY:: Generating a key.
1138 * GPGSM LISTKEYS:: List available keys.
1139 * GPGSM EXPORT:: Export certificates.
1140 * GPGSM IMPORT:: Import certificates.
1141 * GPGSM DELETE:: Delete certificates.
1142 * GPGSM GETINFO:: Information about the process
1147 @subsection Encrypting a Message
1149 Before encryption can be done the recipient must be set using the
1153 RECIPIENT @var{userID}
1156 Set the recipient for the encryption. @var{userID} should be the
1157 internal representation of the key; the server may accept any other way
1158 of specification. If this is a valid and trusted recipient the server
1159 does respond with OK, otherwise the return is an ERR with the reason why
1160 the recipient cannot be used, the encryption will then not be done for
1161 this recipient. If the policy is not to encrypt at all if not all
1162 recipients are valid, the client has to take care of this. All
1163 @code{RECIPIENT} commands are cumulative until a @code{RESET} or an
1164 successful @code{ENCRYPT} command.
1167 INPUT FD[=@var{n}] [--armor|--base64|--binary]
1170 Set the file descriptor for the message to be encrypted to @var{n}.
1171 Obviously the pipe must be open at that point, the server establishes
1172 its own end. If the server returns an error the client should consider
1173 this session failed. If @var{n} is not given, this commands uses the
1174 last file descriptor passed to the application.
1175 @xref{fun-assuan_sendfd, ,the assuan_sendfd function,assuan,the Libassuan
1176 manual}, on how to do descriptor passing.
1178 The @code{--armor} option may be used to advice the server that the
1179 input data is in @acronym{PEM} format, @code{--base64} advices that a
1180 raw base-64 encoding is used, @code{--binary} advices of raw binary
1181 input (@acronym{BER}). If none of these options is used, the server
1182 tries to figure out the used encoding, but this may not always be
1186 OUTPUT FD[=@var{n}] [--armor|--base64]
1189 Set the file descriptor to be used for the output (i.e. the encrypted
1190 message). Obviously the pipe must be open at that point, the server
1191 establishes its own end. If the server returns an error he client
1192 should consider this session failed.
1194 The option armor encodes the output in @acronym{PEM} format, the
1195 @code{--base64} option applies just a base 64 encoding. No option
1196 creates binary output (@acronym{BER}).
1198 The actual encryption is done using the command
1204 It takes the plaintext from the @code{INPUT} command, writes to the
1205 ciphertext to the file descriptor set with the @code{OUTPUT} command,
1206 take the recipients from all the recipients set so far. If this command
1207 fails the clients should try to delete all output currently done or
1208 otherwise mark it as invalid. @command{GPGSM} does ensure that there
1210 security problem with leftover data on the output in this case.
1212 This command should in general not fail, as all necessary checks have
1213 been done while setting the recipients. The input and output pipes are
1218 @subsection Decrypting a message
1220 Input and output FDs are set the same way as in encryption, but
1221 @code{INPUT} refers to the ciphertext and output to the plaintext. There
1222 is no need to set recipients. @command{GPGSM} automatically strips any
1223 @acronym{S/MIME} headers from the input, so it is valid to pass an
1224 entire MIME part to the INPUT pipe.
1226 The encryption is done by using the command
1232 It performs the decrypt operation after doing some check on the internal
1233 state. (e.g. that all needed data has been set). Because it utilizes
1234 the GPG-Agent for the session key decryption, there is no need to ask
1235 the client for a protecting passphrase - GpgAgent takes care of this by
1236 requesting this from the user.
1240 @subsection Signing a Message
1242 Signing is usually done with these commands:
1245 INPUT FD[=@var{n}] [--armor|--base64|--binary]
1248 This tells @command{GPGSM} to read the data to sign from file descriptor @var{n}.
1251 OUTPUT FD[=@var{m}] [--armor|--base64]
1254 Write the output to file descriptor @var{m}. If a detached signature is
1255 requested, only the signature is written.
1261 Sign the data set with the INPUT command and write it to the sink set by
1262 OUTPUT. With @code{--detached}, a detached signature is created
1265 The key used for signing is the default one or the one specified in
1266 the configuration file. To get finer control over the keys, it is
1267 possible to use the command
1273 to the signer's key. @var{userID} should be the
1274 internal representation of the key; the server may accept any other way
1275 of specification. If this is a valid and trusted recipient the server
1276 does respond with OK, otherwise the return is an ERR with the reason why
1277 the key cannot be used, the signature will then not be created using
1278 this key. If the policy is not to sign at all if not all
1279 keys are valid, the client has to take care of this. All
1280 @code{SIGNER} commands are cumulative until a @code{RESET} is done.
1281 Note that a @code{SIGN} does not reset this list of signers which is in
1282 contrats to the @code{RECIPIENT} command.
1286 @subsection Verifying a Message
1288 To verify a mesage the command:
1294 is used. It does a verify operation on the message send to the input FD.
1295 The result is written out using status lines. If an output FD was
1296 given, the signed text will be written to that. If the signature is a
1297 detached one, the server will inquire about the signed material and the
1298 client must provide it.
1301 @subsection Generating a Key
1303 This is used to generate a new keypair, store the secret part in the
1304 @acronym{PSE} and the public key in the key database. We will probably
1305 add optional commands to allow the client to select whether a hardware
1306 token is used to store the key. Configuration options to
1307 @command{GPGSM} can be used to restrict the use of this command.
1313 @command{GPGSM} checks whether this command is allowed and then does an
1314 INQUIRY to get the key parameters, the client should then send the
1315 key parameters in the native format:
1318 S: INQUIRE KEY_PARAM native
1324 Please note that the server may send Status info lines while reading the
1325 data lines from the client. After this the key generation takes place
1326 and the server eventually does send an ERR or OK response. Status lines
1327 may be issued as a progress indicator.
1330 @node GPGSM LISTKEYS
1331 @subsection List available keys
1333 To list the keys in the internal database or using an external key
1334 provider, the command:
1337 LISTKEYS @var{pattern}
1340 is used. To allow multiple patterns (which are ORed during the search)
1341 quoting is required: Spaces are to be translated into "+" or into "%20";
1342 in turn this requires that the usual escape quoting rules are done.
1345 LISTSECRETKEYS @var{pattern}
1348 Lists only the keys where a secret key is available.
1350 The list commands commands are affected by the option
1353 OPTION list-mode=@var{mode}
1359 Use default (which is usually the same as 1).
1361 List only the internal keys.
1363 List only the external keys.
1365 List internal and external keys.
1368 Note that options are valid for the entire session.
1372 @subsection Export certificates
1374 To export certificate from the internal key database the command:
1377 EXPORT [--data [--armor] [--base64]] [--] @var{pattern}
1380 is used. To allow multiple patterns (which are ORed) quoting is
1381 required: Spaces are to be translated into "+" or into "%20"; in turn
1382 this requires that the usual escape quoting rules are done.
1384 If the @option{--data} option has not been given, the format of the
1385 output depends on what was set with the OUTPUT command. When using
1386 @acronym{PEM} encoding a few informational lines are prepended.
1388 If the @option{--data} has been given, a target set via OUTPUT is
1389 ignored and the data is returned inline using standard
1390 @code{D}-lines. This avoids the need for an extra file descriptor. In
1391 this case the options @option{--armor} and @option{--base64} may be used
1392 in the same way as with the OUTPUT command.
1396 @subsection Import certificates
1398 To import certificates into the internal key database, the command
1401 IMPORT [--re-import]
1404 is used. The data is expected on the file descriptor set with the
1405 @code{INPUT} command. Certain checks are performed on the
1406 certificate. Note that the code will also handle PKCS#12 files and
1407 import private keys; a helper program is used for that.
1409 With the option @option{--re-import} the input data is expected to a be
1410 a linefeed separated list of fingerprints. The command will re-import
1411 the corresponding certificates; that is they are made permanent by
1412 removing their ephemeral flag.
1416 @subsection Delete certificates
1418 To delete a certificate the command
1421 DELKEYS @var{pattern}
1424 is used. To allow multiple patterns (which are ORed) quoting is
1425 required: Spaces are to be translated into "+" or into "%20"; in turn
1426 this requires that the usual escape quoting rules are done.
1428 The certificates must be specified unambiguously otherwise an error is
1432 @subsection Return information about the process
1434 This is a multipurpose function to return a variety of information.
1440 The value of @var{what} specifies the kind of information returned:
1443 Return the version of the program.
1445 Return the process id of the process.
1447 Return success if the agent is running.
1448 @item cmd_has_option @var{cmd} @var{opt}
1449 Return success if the command @var{cmd} implements the option @var{opt}.
1450 The leading two dashes usually used with @var{opt} shall not be given.
1456 @command{gpg-agent}(1)
1458 @include see-also-note.texi