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}
262 @opindex export-secret-key-p12
263 Export the private key and the certificate identified by @var{key-id} in
264 a PKCS#12 format. When used 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})
270 @item --export-secret-key-p8 @var{key-id}
271 @itemx --export-secret-key-raw @var{key-id}
272 @opindex export-secret-key-p8
273 @opindex export-secret-key-raw
274 Export the private key of the certificate identified by @var{key-id}
275 with any encryption stripped. The @code{...-raw} command exports in
276 PKCS#1 format; the @code{...-p8} command exports in PKCS#8 format.
277 When used with the @code{--armor} option a few informational lines are
278 prepended to the output. These commands are useful to prepare a key
279 for use on a TLS server.
282 @item --import [@var{files}]
284 Import the certificates from the PEM or binary encoded files as well as
285 from signed-only messages. This command may also be used to import a
286 secret key from a PKCS#12 file.
290 Read information about the private keys from the smartcard and import
291 the certificates from there. This command utilizes the @command{gpg-agent}
292 and in turn the @command{scdaemon}.
294 @item --passwd @var{user_id}
296 Change the passphrase of the private key belonging to the certificate
297 specified as @var{user_id}. Note, that changing the passphrase/PIN of a
298 smartcard is not yet supported.
303 @c *******************************************
304 @c *************** ****************
305 @c *************** OPTIONS ****************
306 @c *************** ****************
307 @c *******************************************
310 @section Option Summary
312 @command{GPGSM} features a bunch of options to control the exact behaviour
313 and to change the default configuration.
316 * Configuration Options:: How to change the configuration.
317 * Certificate Options:: Certificate related options.
318 * Input and Output:: Input and Output.
319 * CMS Options:: How to change how the CMS is created.
320 * Esoteric Options:: Doing things one usually do not want to do.
324 @c *******************************************
325 @c ******** CONFIGURATION OPTIONS **********
326 @c *******************************************
327 @node Configuration Options
328 @subsection How to change the configuration
330 These options are used to change the configuration and are usually found
335 @anchor{gpgsm-option --options}
336 @item --options @var{file}
338 Reads configuration from @var{file} instead of from the default
339 per-user configuration file. The default configuration file is named
340 @file{gpgsm.conf} and expected in the @file{.gnupg} directory directly
341 below the home directory of the user.
343 @include opt-homedir.texi
350 Outputs additional information while running.
351 You can increase the verbosity by giving several
352 verbose commands to @command{gpgsm}, such as @samp{-vv}.
354 @item --policy-file @var{filename}
356 Change the default name of the policy file to @var{filename}.
358 @item --agent-program @var{file}
359 @opindex agent-program
360 Specify an agent program to be used for secret key operations. The
361 default value is the @file{/usr/local/bin/gpg-agent}. This is only used
362 as a fallback when the environment variable @code{GPG_AGENT_INFO} is not
363 set or a running agent cannot be connected.
365 @item --dirmngr-program @var{file}
366 @opindex dirmngr-program
367 Specify a dirmngr program to be used for @acronym{CRL} checks. The
368 default value is @file{/usr/sbin/dirmngr}. This is only used as a
369 fallback when the environment variable @code{DIRMNGR_INFO} is not set or
370 a running dirmngr cannot be connected.
372 @item --prefer-system-dirmngr
373 @opindex prefer-system-dirmngr
374 If a system wide @command{dirmngr} is running in daemon mode, first try
375 to connect to this one. Fallback to a pipe based server if this does
376 not work. Under Windows this option is ignored because the system dirmngr is
379 @item --disable-dirmngr
380 Entirely disable the use of the Dirmngr.
382 @item --no-secmem-warning
383 @opindex no-secmem-warning
384 Do not print a warning when the so called "secure memory" cannot be used.
386 @item --log-file @var{file}
388 When running in server mode, append all logging output to @var{file}.
393 @c *******************************************
394 @c ******** CERTIFICATE OPTIONS ************
395 @c *******************************************
396 @node Certificate Options
397 @subsection Certificate related options
401 @item --enable-policy-checks
402 @itemx --disable-policy-checks
403 @opindex enable-policy-checks
404 @opindex disable-policy-checks
405 By default policy checks are enabled. These options may be used to
408 @item --enable-crl-checks
409 @itemx --disable-crl-checks
410 @opindex enable-crl-checks
411 @opindex disable-crl-checks
412 By default the @acronym{CRL} checks are enabled and the DirMngr is used
413 to check for revoked certificates. The disable option is most useful
414 with an off-line network connection to suppress this check.
416 @item --enable-trusted-cert-crl-check
417 @itemx --disable-trusted-cert-crl-check
418 @opindex enable-trusted-cert-crl-check
419 @opindex disable-trusted-cert-crl-check
420 By default the @acronym{CRL} for trusted root certificates are checked
421 like for any other certificates. This allows a CA to revoke its own
422 certificates voluntary without the need of putting all ever issued
423 certificates into a CRL. The disable option may be used to switch this
424 extra check off. Due to the caching done by the Dirmngr, there will not be
425 any noticeable performance gain. Note, that this also disables possible
426 OCSP checks for trusted root certificates. A more specific way of
427 disabling this check is by adding the ``relax'' keyword to the root CA
428 line of the @file{trustlist.txt}
431 @item --force-crl-refresh
432 @opindex force-crl-refresh
433 Tell the dirmngr to reload the CRL for each request. For better
434 performance, the dirmngr will actually optimize this by suppressing
435 the loading for short time intervals (e.g. 30 minutes). This option
436 is useful to make sure that a fresh CRL is available for certificates
437 hold in the keybox. The suggested way of doing this is by using it
438 along with the option @option{--with-validation} for a key listing
439 command. This option should not be used in a configuration file.
442 @itemx --disable-ocsp
444 @opindex disable-ocsp
445 By default @acronym{OCSP} checks are disabled. The enable option may
446 be used to enable OCSP checks via Dirmngr. If @acronym{CRL} checks
447 are also enabled, CRLs will be used as a fallback if for some reason an
448 OCSP request will not succeed. Note, that you have to allow OCSP
449 requests in Dirmngr's configuration too (option
450 @option{--allow-ocsp}) and configure Dirmngr properly. If you do not do
451 so you will get the error code @samp{Not supported}.
453 @item --auto-issuer-key-retrieve
454 @opindex auto-issuer-key-retrieve
455 If a required certificate is missing while validating the chain of
456 certificates, try to load that certificate from an external location.
457 This usually means that Dirmngr is employed to search for the
458 certificate. Note that this option makes a "web bug" like behavior
459 possible. LDAP server operators can see which keys you request, so by
460 sending you a message signed by a brand new key (which you naturally
461 will not have on your local keybox), the operator can tell both your IP
462 address and the time when you verified the signature.
465 @item --validation-model @var{name}
466 @opindex validation-model
467 This option changes the default validation model. The only possible
468 values are "shell" (which is the default), "chain" which forces the
469 use of the chain model and "steed" for a new simplified model. The
470 chain model is also used if an option in the @file{trustlist.txt} or
471 an attribute of the certificate requests it. However the standard
472 model (shell) is in that case always tried first.
474 @item --ignore-cert-extension @var{oid}
475 @opindex ignore-cert-extension
476 Add @var{oid} to the list of ignored certificate extensions. The
477 @var{oid} is expected to be in dotted decimal form, like
478 @code{2.5.29.3}. This option may be used more than once. Critical
479 flagged certificate extensions matching one of the OIDs in the list
480 are treated as if they are actually handled and thus the certificate
481 will not be rejected due to an unknown critical extension. Use this
482 option with care because extensions are usually flagged as critical
487 @c *******************************************
488 @c *********** INPUT AND OUTPUT ************
489 @c *******************************************
490 @node Input and Output
491 @subsection Input and Output
497 Create PEM encoded output. Default is binary output.
501 Create Base-64 encoded output; i.e. PEM without the header lines.
504 @opindex assume-armor
505 Assume the input data is PEM encoded. Default is to autodetect the
506 encoding but this is may fail.
508 @item --assume-base64
509 @opindex assume-base64
510 Assume the input data is plain base-64 encoded.
512 @item --assume-binary
513 @opindex assume-binary
514 Assume the input data is binary encoded.
516 @anchor{option --p12-charset}
517 @item --p12-charset @var{name}
519 @command{gpgsm} uses the UTF-8 encoding when encoding passphrases for
520 PKCS#12 files. This option may be used to force the passphrase to be
521 encoded in the specified encoding @var{name}. This is useful if the
522 application used to import the key uses a different encoding and thus
523 will not be able to import a file generated by @command{gpgsm}. Commonly
524 used values for @var{name} are @code{Latin1} and @code{CP850}. Note
525 that @command{gpgsm} itself automagically imports any file with a
526 passphrase encoded to the most commonly used encodings.
529 @item --default-key @var{user_id}
531 Use @var{user_id} as the standard key for signing. This key is used if
532 no other key has been defined as a signing key. Note, that the first
533 @option{--local-users} option also sets this key if it has not yet been
534 set; however @option{--default-key} always overrides this.
537 @item --local-user @var{user_id}
538 @item -u @var{user_id}
540 Set the user(s) to be used for signing. The default is the first
541 secret key found in the database.
544 @item --recipient @var{name}
547 Encrypt to the user id @var{name}. There are several ways a user id
548 may be given (@pxref{how-to-specify-a-user-id}).
551 @item --output @var{file}
554 Write output to @var{file}. The default is to write it to stdout.
557 @item --with-key-data
558 @opindex with-key-data
559 Displays extra information with the @code{--list-keys} commands. Especially
560 a line tagged @code{grp} is printed which tells you the keygrip of a
561 key. This string is for example used as the file name of the
564 @item --with-validation
565 @opindex with-validation
566 When doing a key listing, do a full validation check for each key and
567 print the result. This is usually a slow operation because it
568 requires a CRL lookup and other operations.
570 When used along with --import, a validation of the certificate to
571 import is done and only imported if it succeeds the test. Note that
572 this does not affect an already available certificate in the DB.
573 This option is therefore useful to simply verify a certificate.
576 @item --with-md5-fingerprint
577 For standard key listings, also print the MD5 fingerprint of the
581 Include the keygrip in standard key listings. Note that the keygrip is
582 always listed in --with-colons mode.
587 Include info about the presence of a secret key in public key listings
588 done with @code{--with-colons}.
593 @c *******************************************
594 @c ************* CMS OPTIONS ***************
595 @c *******************************************
597 @subsection How to change how the CMS is created.
600 @item --include-certs @var{n}
601 @opindex include-certs
602 Using @var{n} of -2 includes all certificate except for the root cert,
603 -1 includes all certs, 0 does not include any certs, 1 includes only the
604 signers cert and all other positive values include up to @var{n}
605 certificates starting with the signer cert. The default is -2.
607 @item --cipher-algo @var{oid}
609 Use the cipher algorithm with the ASN.1 object identifier @var{oid} for
610 encryption. For convenience the strings @code{3DES}, @code{AES} and
611 @code{AES256} may be used instead of their OIDs. The default is
612 @code{AES} (2.16.840.1.101.3.4.1.2).
614 @item --digest-algo @code{name}
615 Use @code{name} as the message digest algorithm. Usually this
616 algorithm is deduced from the respective signing certificate. This
617 option forces the use of the given algorithm and may lead to severe
618 interoperability problems.
624 @c *******************************************
625 @c ******** ESOTERIC OPTIONS ***************
626 @c *******************************************
627 @node Esoteric Options
628 @subsection Doing things one usually do not want to do.
633 @item --extra-digest-algo @var{name}
634 @opindex extra-digest-algo
635 Sometimes signatures are broken in that they announce a different digest
636 algorithm than actually used. @command{gpgsm} uses a one-pass data
637 processing model and thus needs to rely on the announced digest
638 algorithms to properly hash the data. As a workaround this option may
639 be used to tell gpg to also hash the data using the algorithm
640 @var{name}; this slows processing down a little bit but allows to verify
641 such broken signatures. If @command{gpgsm} prints an error like
642 ``digest algo 8 has not been enabled'' you may want to try this option,
643 with @samp{SHA256} for @var{name}.
646 @item --faked-system-time @var{epoch}
647 @opindex faked-system-time
648 This option is only useful for testing; it sets the system time back or
649 forth to @var{epoch} which is the number of seconds elapsed since the year
650 1970. Alternatively @var{epoch} may be given as a full ISO time string
651 (e.g. "20070924T154812").
653 @item --with-ephemeral-keys
654 @opindex with-ephemeral-keys
655 Include ephemeral flagged keys in the output of key listings. Note
656 that they are included anyway if the key specification for a listing
657 is given as fingerprint or keygrip.
659 @item --debug-level @var{level}
661 Select the debug level for investigating problems. @var{level} may be
662 a numeric value or by a keyword:
666 No debugging at all. A value of less than 1 may be used instead of
669 Some basic debug messages. A value between 1 and 2 may be used
670 instead of the keyword.
672 More verbose debug messages. A value between 3 and 5 may be used
673 instead of the keyword.
675 Even more detailed messages. A value between 6 and 8 may be used
676 instead of the keyword.
678 All of the debug messages you can get. A value greater than 8 may be
679 used instead of the keyword. The creation of hash tracing files is
680 only enabled if the keyword is used.
683 How these messages are mapped to the actual debugging flags is not
684 specified and may change with newer releases of this program. They are
685 however carefully selected to best aid in debugging.
687 @item --debug @var{flags}
689 This option is only useful for debugging and the behaviour may change
690 at any time without notice; using @code{--debug-levels} is the
691 preferred method to select the debug verbosity. FLAGS are bit encoded
692 and may be given in usual C-Syntax. The currently defined bits are:
696 X.509 or OpenPGP protocol related data
698 values of big number integers
700 low level crypto operations
706 show memory statistics.
708 write hashed data to files named @code{dbgmd-000*}
710 trace Assuan protocol
713 Note, that all flags set using this option may get overridden by
714 @code{--debug-level}.
718 Same as @code{--debug=0xffffffff}
720 @item --debug-allow-core-dump
721 @opindex debug-allow-core-dump
722 Usually @command{gpgsm} tries to avoid dumping core by well written code and by
723 disabling core dumps for security reasons. However, bugs are pretty
724 durable beasts and to squash them it is sometimes useful to have a core
725 dump. This option enables core dumps unless the Bad Thing happened
726 before the option parsing.
728 @item --debug-no-chain-validation
729 @opindex debug-no-chain-validation
730 This is actually not a debugging option but only useful as such. It
731 lets @command{gpgsm} bypass all certificate chain validation checks.
733 @item --debug-ignore-expiration
734 @opindex debug-ignore-expiration
735 This is actually not a debugging option but only useful as such. It
736 lets @command{gpgsm} ignore all notAfter dates, this is used by the regression
739 @item --fixed-passphrase @var{string}
740 @opindex fixed-passphrase
741 Supply the passphrase @var{string} to the gpg-protect-tool. This
742 option is only useful for the regression tests included with this
743 package and may be revised or removed at any time without notice.
745 @item --no-common-certs-import
746 @opindex no-common-certs-import
747 Suppress the import of common certificates on keybox creation.
751 All the long options may also be given in the configuration file after
752 stripping off the two leading dashes.
754 @c *******************************************
755 @c *************** ****************
756 @c *************** USER ID ****************
757 @c *************** ****************
758 @c *******************************************
759 @mansect how to specify a user id
761 @include specify-user-id.texi
764 @c *******************************************
765 @c *************** ****************
766 @c *************** FILES ****************
767 @c *************** ****************
768 @c *******************************************
770 @node GPGSM Configuration
771 @section Configuration files
773 There are a few configuration files to control certain aspects of
774 @command{gpgsm}'s operation. Unless noted, they are expected in the
775 current home directory (@pxref{option --homedir}).
781 This is the standard configuration file read by @command{gpgsm} on
782 startup. It may contain any valid long option; the leading two dashes
783 may not be entered and the option may not be abbreviated. This default
784 name may be changed on the command line (@pxref{gpgsm-option --options}).
785 You should backup this file.
790 This is a list of allowed CA policies. This file should list the
791 object identifiers of the policies line by line. Empty lines and
792 lines starting with a hash mark are ignored. Policies missing in this
793 file and not marked as critical in the certificate will print only a
794 warning; certificates with policies marked as critical and not listed
795 in this file will fail the signature verification. You should backup
798 For example, to allow only the policy 2.289.9.9, the file should look
809 @cindex qualified.txt
810 This is the list of root certificates used for qualified certificates.
811 They are defined as certificates capable of creating legally binding
812 signatures in the same way as handwritten signatures are. Comments
813 start with a hash mark and empty lines are ignored. Lines do have a
814 length limit but this is not a serious limitation as the format of the
815 entries is fixed and checked by gpgsm: A non-comment line starts with
816 optional whitespace, followed by exactly 40 hex character, white space
817 and a lowercased 2 letter country code. Additional data delimited with
818 by a white space is current ignored but might late be used for other
821 Note that even if a certificate is listed in this file, this does not
822 mean that the certificate is trusted; in general the certificates listed
823 in this file need to be listed also in @file{trustlist.txt}.
825 This is a global file an installed in the data directory
826 (e.g. @file{/usr/share/gnupg/qualified.txt}). GnuPG installs a suitable
827 file with root certificates as used in Germany. As new Root-CA
828 certificates may be issued over time, these entries may need to be
829 updated; new distributions of this software should come with an updated
830 list but it is still the responsibility of the Administrator to check
831 that this list is correct.
833 Everytime @command{gpgsm} uses a certificate for signing or verification
834 this file will be consulted to check whether the certificate under
835 question has ultimately been issued by one of these CAs. If this is the
836 case the user will be informed that the verified signature represents a
837 legally binding (``qualified'') signature. When creating a signature
838 using such a certificate an extra prompt will be issued to let the user
839 confirm that such a legally binding signature shall really be created.
841 Because this software has not yet been approved for use with such
842 certificates, appropriate notices will be shown to indicate this fact.
846 This is plain text file with a few help entries used with
847 @command{pinentry} as well as a large list of help items for
848 @command{gpg} and @command{gpgsm}. The standard file has English help
849 texts; to install localized versions use filenames like @file{help.LL.txt}
850 with LL denoting the locale. GnuPG comes with a set of predefined help
851 files in the data directory (e.g. @file{/usr/share/gnupg/help.de.txt})
852 and allows overriding of any help item by help files stored in the
853 system configuration directory (e.g. @file{/etc/gnupg/help.de.txt}).
854 For a reference of the help file's syntax, please see the installed
855 @file{help.txt} file.
859 @cindex com-certs.pem
860 This file is a collection of common certificates used to populated a
861 newly created @file{pubring.kbx}. An administrator may replace this
862 file with a custom one. The format is a concatenation of PEM encoded
863 X.509 certificates. This global file is installed in the data directory
864 (e.g. @file{/usr/share/gnupg/com-certs.pem}).
869 Note that on larger installations, it is useful to put predefined files
870 into the directory @file{/etc/skel/.gnupg/} so that newly created users
871 start up with a working configuration. For existing users a small
872 helper script is provided to create these files (@pxref{addgnupghome}).
874 For internal purposes gpgsm creates and maintains a few other files;
875 they all live in in the current home directory (@pxref{option
876 --homedir}). Only @command{gpgsm} may modify these files.
882 This a database file storing the certificates as well as meta
883 information. For debugging purposes the tool @command{kbxutil} may be
884 used to show the internal structure of this file. You should backup
889 This content of this file is used to maintain the internal state of the
890 random number generator across invocations. The same file is used by
891 other programs of this software too.
895 If this file exists and the environment variable @env{GPG_AGENT_INFO} is
896 not set, @command{gpgsm} will first try to connect to this socket for
897 accessing @command{gpg-agent} before starting a new @command{gpg-agent}
898 instance. Under Windows this socket (which in reality be a plain file
899 describing a regular TCP listening port) is the standard way of
900 connecting the @command{gpg-agent}.
905 @c *******************************************
906 @c *************** ****************
907 @c *************** EXAMPLES ****************
908 @c *************** ****************
909 @c *******************************************
915 $ gpgsm -er goo@@bar.net <plaintext >ciphertext
919 @c *******************************************
920 @c *************** **************
921 @c *************** UNATTENDED **************
922 @c *************** **************
923 @c *******************************************
925 @node Unattended Usage
926 @section Unattended Usage
928 @command{gpgsm} is often used as a backend engine by other software. To help
929 with this a machine interface has been defined to have an unambiguous
930 way to do this. This is most likely used with the @code{--server} command
931 but may also be used in the standard operation mode by using the
932 @code{--status-fd} option.
935 * Automated signature checking:: Automated signature checking.
936 * CSR and certificate creation:: CSR and certificate creation.
939 @node Automated signature checking
940 @subsection Automated signature checking
942 It is very important to understand the semantics used with signature
943 verification. Checking a signature is not as simple as it may sound and
944 so the operation is a bit complicated. In most cases it is required
945 to look at several status lines. Here is a table of all cases a signed
949 @item The signature is valid
950 This does mean that the signature has been successfully verified, the
951 certificates are all sane. However there are two subcases with
952 important information: One of the certificates may have expired or a
953 signature of a message itself as expired. It is a sound practise to
954 consider such a signature still as valid but additional information
955 should be displayed. Depending on the subcase @command{gpgsm} will issue
958 @item signature valid and nothing did expire
959 @code{GOODSIG}, @code{VALIDSIG}, @code{TRUST_FULLY}
960 @item signature valid but at least one certificate has expired
961 @code{EXPKEYSIG}, @code{VALIDSIG}, @code{TRUST_FULLY}
962 @item signature valid but expired
963 @code{EXPSIG}, @code{VALIDSIG}, @code{TRUST_FULLY}
964 Note, that this case is currently not implemented.
967 @item The signature is invalid
968 This means that the signature verification failed (this is an indication
969 of af a transfer error, a program error or tampering with the message).
970 @command{gpgsm} issues one of these status codes sequences:
973 @item @code{GOODSIG}, @code{VALIDSIG} @code{TRUST_NEVER}
976 @item Error verifying a signature
977 For some reason the signature could not be verified, i.e. it cannot be
978 decided whether the signature is valid or invalid. A common reason for
979 this is a missing certificate.
983 @node CSR and certificate creation
984 @subsection CSR and certificate creation
987 @strong{Please notice}: The immediate creation of certificates is only
988 supported by GnuPG version 2.1 or later. With a 2.0 version you may
992 The command @option{--gen-key} may be used along with the option
993 @option{--batch} to either create a certificate signing request (CSR)
994 or an X.509 certificate. The is controlled by a parameter file; the
995 format of this file is as follows:
998 @item Text only, line length is limited to about 1000 characters.
999 @item UTF-8 encoding must be used to specify non-ASCII characters.
1000 @item Empty lines are ignored.
1001 @item Leading and trailing while space is ignored.
1002 @item A hash sign as the first non white space character indicates
1004 @item Control statements are indicated by a leading percent sign, the
1005 arguments are separated by white space from the keyword.
1006 @item Parameters are specified by a keyword, followed by a colon. Arguments
1007 are separated by white space.
1008 @item The first parameter must be @samp{Key-Type}, control statements
1009 may be placed anywhere.
1011 The order of the parameters does not matter except for @samp{Key-Type}
1012 which must be the first parameter. The parameters are only used for
1013 the generated CSR/certificate; parameters from previous sets are not
1014 used. Some syntactically checks may be performed.
1016 Key generation takes place when either the end of the parameter file
1017 is reached, the next @samp{Key-Type} parameter is encountered or at the
1018 control statement @samp{%commit} is encountered.
1026 @item %echo @var{text}
1027 Print @var{text} as diagnostic.
1030 Suppress actual key generation (useful for syntax checking).
1033 Perform the key generation. Note that an implicit commit is done at
1034 the next @asis{Key-Type} parameter.
1036 @c %certfile <filename>
1037 @c [Not yet implemented!]
1038 @c Do not write the certificate to the keyDB but to <filename>.
1039 @c This must be given before the first
1040 @c commit to take place, duplicate specification of the same filename
1041 @c is ignored, the last filename before a commit is used.
1042 @c The filename is used until a new filename is used (at commit points)
1043 @c and all keys are written to that file. If a new filename is given,
1044 @c this file is created (and overwrites an existing one).
1045 @c Both control statements must be given.
1053 @item Key-Type: @var{algo}
1054 Starts a new parameter block by giving the type of the primary
1055 key. The algorithm must be capable of signing. This is a required
1056 parameter. The only supported value for @var{algo} is @samp{rsa}.
1058 @item Key-Length: @var{nbits}
1059 The requested length of a generated key in bits. Defaults to 2048.
1061 @item Key-Grip: @var{hexstring}
1062 This is optional and used to generate a CSR or certificatet for an
1063 already existing key. Key-Length will be ignored when given.
1065 @item Key-Usage: @var{usage-list}
1066 Space or comma delimited list of key usage, allowed values are
1067 @samp{encrypt}, @samp{sign} and @samp{cert}. This is used to generate
1068 the keyUsage extension. Please make sure that the algorithm is
1069 capable of this usage. Default is to allow encrypt and sign.
1071 @item Name-DN: @var{subject-name}
1072 This is the Distinguished Name (DN) of the subject in RFC-2253 format.
1074 @item Name-Email: @var{string}
1075 This is an email address for the altSubjectName. This parameter is
1076 optional but may occur several times to add several email addresses to
1079 @item Name-DNS: @var{string}
1080 The is an DNS name for the altSubjectName. This parameter is optional
1081 but may occur several times to add several DNS names to a certificate.
1083 @item Name-URI: @var{string}
1084 This is an URI for the altSubjectName. This parameter is optional but
1085 may occur several times to add several URIs to a certificate.
1089 Additional parameters used to create a certificate (in contrast to a
1090 certificate signing request):
1094 @item Serial: @var{sn}
1095 If this parameter is given an X.509 certificate will be generated.
1096 @var{sn} is expected to be a hex string representing an unsigned
1097 integer of arbitary length. The special value @samp{random} can be
1098 used to create a 64 bit random serial number.
1100 @item Issuer-DN: @var{issuer-name}
1101 This is the DN name of the issuer in rfc2253 format. If it is not set
1102 it will default to the subject DN and a special GnuPG extension will
1103 be included in the certificate to mark it as a standalone certificate.
1105 @item Creation-Date: @var{iso-date}
1106 @itemx Not-Before: @var{iso-date}
1107 Set the notBefore date of the certificate. Either a date like
1108 @samp{1986-04-26} or @samp{1986-04-26 12:00} or a standard ISO
1109 timestamp like @samp{19860426T042640} may be used. The time is
1110 considered to be UTC. If it is not given the current date is used.
1112 @item Expire-Date: @var{iso-date}
1113 @itemx Not-After: @var{iso-date}
1114 Set the notAfter date of the certificate. Either a date like
1115 @samp{2063-04-05} or @samp{2063-04-05 17:00} or a standard ISO
1116 timestamp like @samp{20630405T170000} may be used. The time is
1117 considered to be UTC. If it is not given a default value in the not
1118 too far future is used.
1120 @item Signing-Key: @var{keygrip}
1121 This gives the keygrip of the key used to sign the certificate. If it
1122 is not given a self-signed certificate will be created. For
1123 compatibility with future versions, it is suggested to prefix the
1124 keygrip with a @samp{&}.
1126 @item Hash-Algo: @var{hash-algo}
1127 Use @var{hash-algo} for this CSR or certificate. The supported hash
1128 algorithms are: @samp{sha1}, @samp{sha256}, @samp{sha384} and
1129 @samp{sha512}; they may also be specified with uppercase letters. The
1130 default is @samp{sha256}.
1134 @c *******************************************
1135 @c *************** *****************
1136 @c *************** ASSSUAN *****************
1137 @c *************** *****************
1138 @c *******************************************
1139 @node GPGSM Protocol
1140 @section The Protocol the Server Mode Uses.
1142 Description of the protocol used to access @command{GPGSM}.
1143 @command{GPGSM} does implement the Assuan protocol and in addition
1144 provides a regular command line interface which exhibits a full client
1145 to this protocol (but uses internal linking). To start
1146 @command{gpgsm} as a server the command line the option
1147 @code{--server} must be used. Additional options are provided to
1148 select the communication method (i.e. the name of the socket).
1150 We assume that the connection has already been established; see the
1151 Assuan manual for details.
1154 * GPGSM ENCRYPT:: Encrypting a message.
1155 * GPGSM DECRYPT:: Decrypting a message.
1156 * GPGSM SIGN:: Signing a message.
1157 * GPGSM VERIFY:: Verifying a message.
1158 * GPGSM GENKEY:: Generating a key.
1159 * GPGSM LISTKEYS:: List available keys.
1160 * GPGSM EXPORT:: Export certificates.
1161 * GPGSM IMPORT:: Import certificates.
1162 * GPGSM DELETE:: Delete certificates.
1163 * GPGSM GETINFO:: Information about the process
1168 @subsection Encrypting a Message
1170 Before encryption can be done the recipient must be set using the
1174 RECIPIENT @var{userID}
1177 Set the recipient for the encryption. @var{userID} should be the
1178 internal representation of the key; the server may accept any other way
1179 of specification. If this is a valid and trusted recipient the server
1180 does respond with OK, otherwise the return is an ERR with the reason why
1181 the recipient cannot be used, the encryption will then not be done for
1182 this recipient. If the policy is not to encrypt at all if not all
1183 recipients are valid, the client has to take care of this. All
1184 @code{RECIPIENT} commands are cumulative until a @code{RESET} or an
1185 successful @code{ENCRYPT} command.
1188 INPUT FD[=@var{n}] [--armor|--base64|--binary]
1191 Set the file descriptor for the message to be encrypted to @var{n}.
1192 Obviously the pipe must be open at that point, the server establishes
1193 its own end. If the server returns an error the client should consider
1194 this session failed. If @var{n} is not given, this commands uses the
1195 last file descriptor passed to the application.
1196 @xref{fun-assuan_sendfd, ,the assuan_sendfd function,assuan,the Libassuan
1197 manual}, on how to do descriptor passing.
1199 The @code{--armor} option may be used to advice the server that the
1200 input data is in @acronym{PEM} format, @code{--base64} advices that a
1201 raw base-64 encoding is used, @code{--binary} advices of raw binary
1202 input (@acronym{BER}). If none of these options is used, the server
1203 tries to figure out the used encoding, but this may not always be
1207 OUTPUT FD[=@var{n}] [--armor|--base64]
1210 Set the file descriptor to be used for the output (i.e. the encrypted
1211 message). Obviously the pipe must be open at that point, the server
1212 establishes its own end. If the server returns an error he client
1213 should consider this session failed.
1215 The option armor encodes the output in @acronym{PEM} format, the
1216 @code{--base64} option applies just a base 64 encoding. No option
1217 creates binary output (@acronym{BER}).
1219 The actual encryption is done using the command
1225 It takes the plaintext from the @code{INPUT} command, writes to the
1226 ciphertext to the file descriptor set with the @code{OUTPUT} command,
1227 take the recipients from all the recipients set so far. If this command
1228 fails the clients should try to delete all output currently done or
1229 otherwise mark it as invalid. @command{GPGSM} does ensure that there
1231 security problem with leftover data on the output in this case.
1233 This command should in general not fail, as all necessary checks have
1234 been done while setting the recipients. The input and output pipes are
1239 @subsection Decrypting a message
1241 Input and output FDs are set the same way as in encryption, but
1242 @code{INPUT} refers to the ciphertext and output to the plaintext. There
1243 is no need to set recipients. @command{GPGSM} automatically strips any
1244 @acronym{S/MIME} headers from the input, so it is valid to pass an
1245 entire MIME part to the INPUT pipe.
1247 The encryption is done by using the command
1253 It performs the decrypt operation after doing some check on the internal
1254 state. (e.g. that all needed data has been set). Because it utilizes
1255 the GPG-Agent for the session key decryption, there is no need to ask
1256 the client for a protecting passphrase - GpgAgent takes care of this by
1257 requesting this from the user.
1261 @subsection Signing a Message
1263 Signing is usually done with these commands:
1266 INPUT FD[=@var{n}] [--armor|--base64|--binary]
1269 This tells @command{GPGSM} to read the data to sign from file descriptor @var{n}.
1272 OUTPUT FD[=@var{m}] [--armor|--base64]
1275 Write the output to file descriptor @var{m}. If a detached signature is
1276 requested, only the signature is written.
1282 Sign the data set with the INPUT command and write it to the sink set by
1283 OUTPUT. With @code{--detached}, a detached signature is created
1286 The key used for signing is the default one or the one specified in
1287 the configuration file. To get finer control over the keys, it is
1288 possible to use the command
1294 to the signer's key. @var{userID} should be the
1295 internal representation of the key; the server may accept any other way
1296 of specification. If this is a valid and trusted recipient the server
1297 does respond with OK, otherwise the return is an ERR with the reason why
1298 the key cannot be used, the signature will then not be created using
1299 this key. If the policy is not to sign at all if not all
1300 keys are valid, the client has to take care of this. All
1301 @code{SIGNER} commands are cumulative until a @code{RESET} is done.
1302 Note that a @code{SIGN} does not reset this list of signers which is in
1303 contrats to the @code{RECIPIENT} command.
1307 @subsection Verifying a Message
1309 To verify a mesage the command:
1315 is used. It does a verify operation on the message send to the input FD.
1316 The result is written out using status lines. If an output FD was
1317 given, the signed text will be written to that. If the signature is a
1318 detached one, the server will inquire about the signed material and the
1319 client must provide it.
1322 @subsection Generating a Key
1324 This is used to generate a new keypair, store the secret part in the
1325 @acronym{PSE} and the public key in the key database. We will probably
1326 add optional commands to allow the client to select whether a hardware
1327 token is used to store the key. Configuration options to
1328 @command{GPGSM} can be used to restrict the use of this command.
1334 @command{GPGSM} checks whether this command is allowed and then does an
1335 INQUIRY to get the key parameters, the client should then send the
1336 key parameters in the native format:
1339 S: INQUIRE KEY_PARAM native
1345 Please note that the server may send Status info lines while reading the
1346 data lines from the client. After this the key generation takes place
1347 and the server eventually does send an ERR or OK response. Status lines
1348 may be issued as a progress indicator.
1351 @node GPGSM LISTKEYS
1352 @subsection List available keys
1354 To list the keys in the internal database or using an external key
1355 provider, the command:
1358 LISTKEYS @var{pattern}
1361 is used. To allow multiple patterns (which are ORed during the search)
1362 quoting is required: Spaces are to be translated into "+" or into "%20";
1363 in turn this requires that the usual escape quoting rules are done.
1366 LISTSECRETKEYS @var{pattern}
1369 Lists only the keys where a secret key is available.
1371 The list commands commands are affected by the option
1374 OPTION list-mode=@var{mode}
1380 Use default (which is usually the same as 1).
1382 List only the internal keys.
1384 List only the external keys.
1386 List internal and external keys.
1389 Note that options are valid for the entire session.
1393 @subsection Export certificates
1395 To export certificate from the internal key database the command:
1398 EXPORT [--data [--armor] [--base64]] [--] @var{pattern}
1401 is used. To allow multiple patterns (which are ORed) quoting is
1402 required: Spaces are to be translated into "+" or into "%20"; in turn
1403 this requires that the usual escape quoting rules are done.
1405 If the @option{--data} option has not been given, the format of the
1406 output depends on what was set with the OUTPUT command. When using
1407 @acronym{PEM} encoding a few informational lines are prepended.
1409 If the @option{--data} has been given, a target set via OUTPUT is
1410 ignored and the data is returned inline using standard
1411 @code{D}-lines. This avoids the need for an extra file descriptor. In
1412 this case the options @option{--armor} and @option{--base64} may be used
1413 in the same way as with the OUTPUT command.
1417 @subsection Import certificates
1419 To import certificates into the internal key database, the command
1422 IMPORT [--re-import]
1425 is used. The data is expected on the file descriptor set with the
1426 @code{INPUT} command. Certain checks are performed on the
1427 certificate. Note that the code will also handle PKCS#12 files and
1428 import private keys; a helper program is used for that.
1430 With the option @option{--re-import} the input data is expected to a be
1431 a linefeed separated list of fingerprints. The command will re-import
1432 the corresponding certificates; that is they are made permanent by
1433 removing their ephemeral flag.
1437 @subsection Delete certificates
1439 To delete a certificate the command
1442 DELKEYS @var{pattern}
1445 is used. To allow multiple patterns (which are ORed) quoting is
1446 required: Spaces are to be translated into "+" or into "%20"; in turn
1447 this requires that the usual escape quoting rules are done.
1449 The certificates must be specified unambiguously otherwise an error is
1453 @subsection Return information about the process
1455 This is a multipurpose function to return a variety of information.
1461 The value of @var{what} specifies the kind of information returned:
1464 Return the version of the program.
1466 Return the process id of the process.
1468 Return success if the agent is running.
1469 @item cmd_has_option @var{cmd} @var{opt}
1470 Return success if the command @var{cmd} implements the option @var{opt}.
1471 The leading two dashes usually used with @var{opt} shall not be given.
1477 @command{gpg-agent}(1)
1479 @include see-also-note.texi