1 @c Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
2 @c 2008, 2009, 2010 Free Software Foundation, Inc.
3 @c This is part of the GnuPG manual.
4 @c For copying conditions, see the file gnupg.texi.
10 @cindex GPG command options
11 @cindex command options
12 @cindex options, GPG command
15 @c Begin standard stuff
20 \- OpenPGP encryption and signing tool
37 @c Begin gpg2 hack stuff
42 \- OpenPGP encryption and signing tool
57 @c End gpg2 hack stuff
61 @command{@gpgname} is the OpenPGP part of the GNU Privacy Guard (GnuPG). It
62 is a tool to provide digital encryption and signing services using the
63 OpenPGP standard. @command{@gpgname} features complete key management and
64 all the bells and whistles you would expect from a full OpenPGP
67 There are two main versions of GnuPG: GnuPG 1.x and GnuPG 2.x. GnuPG
68 2.x supports modern encryption algorithms and thus should be preferred
69 over GnuPG 1.x. You only need to use GnuPG 1.x if your platform
70 doesn't support GnuPG 2.x, or you need support for some features that
71 GnuPG 2.x has deprecated, e.g., decrypting data created with PGP-2
75 If you are looking for version 1 of GnuPG, you may find that version
76 installed under the name @command{gpg1}.
79 In contrast to the standalone command @command{gpg} from GnuPG 1.x,
80 the 2.x version is commonly installed under the name
86 @xref{Option Index}, for an index to @command{@gpgname}'s commands and options.
90 * GPG Commands:: List of all commands.
91 * GPG Options:: List of all options.
92 * GPG Configuration:: Configuration files.
93 * GPG Examples:: Some usage examples.
95 Developer information:
96 * Unattended Usage of GPG:: Using @command{gpg} from other programs.
99 @c * GPG Protocol:: The protocol the server mode uses.
102 @c *******************************************
103 @c *************** ****************
104 @c *************** COMMANDS ****************
105 @c *************** ****************
106 @c *******************************************
111 Commands are not distinguished from options except for the fact that
112 only one command is allowed. Generally speaking, irrelevant options
113 are silently ignored, and may not be checked for correctness.
115 @command{@gpgname} may be run with no commands. In this case it will
116 perform a reasonable action depending on the type of file it is given
117 as input (an encrypted message is decrypted, a signature is verified,
118 a file containing keys is listed, etc.).
122 * General GPG Commands:: Commands not specific to the functionality.
123 * Operational GPG Commands:: Commands to select the type of operation.
124 * OpenPGP Key Management:: How to manage your keys.
128 @c *******************************************
129 @c ********** GENERAL COMMANDS *************
130 @c *******************************************
131 @node General GPG Commands
132 @subsection Commands not specific to the function
137 Print the program version and licensing information. Note that you
138 cannot abbreviate this command.
143 Print a usage message summarizing the most useful command-line options.
144 Note that you cannot abbreviate this command.
148 Print warranty information.
151 @opindex dump-options
152 Print a list of all available options and commands. Note that you cannot
153 abbreviate this command.
157 @c *******************************************
158 @c ******** OPERATIONAL COMMANDS ***********
159 @c *******************************************
160 @node Operational GPG Commands
161 @subsection Commands to select the type of operation
169 Sign a message. This command may be combined with @option{--encrypt}
170 (to sign and encrypt a message), @option{--symmetric} (to sign and
171 symmetrically encrypt a message), or both @option{--encrypt} and
172 @option{--symmetric} (to sign and encrypt a message that can be
173 decrypted using a secret key or a passphrase). The signing key is
174 chosen by default or can be set explicitly using the
175 @option{--local-user} and @option{--default-key} options.
181 Make a cleartext signature. The content in a cleartext signature is
182 readable without any special software. OpenPGP software is only needed
183 to verify the signature. cleartext signatures may modify end-of-line
184 whitespace for platform independence and are not intended to be
185 reversible. The signing key is chosen by default or can be set
186 explicitly using the @option{--local-user} and @option{--default-key}
193 Make a detached signature.
198 Encrypt data. This command may be combined with @option{--sign} (to
199 sign and encrypt a message), @option{--symmetric} (to encrypt a
200 message that can decrypted using a secret key or a passphrase), or
201 @option{--sign} and @option{--symmetric} together (for a signed
202 message that can be decrypted using a secret key or a passphrase).
207 Encrypt with a symmetric cipher using a passphrase. The default
208 symmetric cipher used is @value{GPGSYMENCALGO}, but may be chosen with the
209 @option{--cipher-algo} option. This command may be combined with
210 @option{--sign} (for a signed and symmetrically encrypted message),
211 @option{--encrypt} (for a message that may be decrypted via a secret key
212 or a passphrase), or @option{--sign} and @option{--encrypt} together
213 (for a signed message that may be decrypted via a secret key or a
218 Store only (make a simple literal data packet).
223 Decrypt the file given on the command line (or STDIN if no file
224 is specified) and write it to STDOUT (or the file specified with
225 @option{--output}). If the decrypted file is signed, the signature is also
226 verified. This command differs from the default operation, as it never
227 writes to the filename which is included in the file and it rejects
228 files that don't begin with an encrypted message.
232 Assume that the first argument is a signed file and verify it without
233 generating any output. With no arguments, the signature packet is
234 read from STDIN. If only one argument is given, the specified file is
235 expected to include a complete signature.
237 With more than one argument, the first argument should specify a file
238 with a detached signature and the remaining files should contain the
239 signed data. To read the signed data from STDIN, use @samp{-} as the
240 second filename. For security reasons, a detached signature will not
241 read the signed material from STDIN if not explicitly specified.
243 Note: If the option @option{--batch} is not used, @command{@gpgname}
244 may assume that a single argument is a file with a detached signature,
245 and it will try to find a matching data file by stripping certain
246 suffixes. Using this historical feature to verify a detached
247 signature is strongly discouraged; you should always specify the data file
250 Note: When verifying a cleartext signature, @command{@gpgname} verifies
251 only what makes up the cleartext signed data and not any extra data
252 outside of the cleartext signature or the header lines directly following
253 the dash marker line. The option @code{--output} may be used to write
254 out the actual signed data, but there are other pitfalls with this
255 format as well. It is suggested to avoid cleartext signatures in
256 favor of detached signatures.
260 This modifies certain other commands to accept multiple files for
261 processing on the command line or read from STDIN with each filename on
262 a separate line. This allows for many files to be processed at
263 once. @option{--multifile} may currently be used along with
264 @option{--verify}, @option{--encrypt}, and @option{--decrypt}. Note that
265 @option{--multifile --verify} may not be used with detached signatures.
268 @opindex verify-files
269 Identical to @option{--multifile --verify}.
271 @item --encrypt-files
272 @opindex encrypt-files
273 Identical to @option{--multifile --encrypt}.
275 @item --decrypt-files
276 @opindex decrypt-files
277 Identical to @option{--multifile --decrypt}.
281 @itemx --list-public-keys
283 List the specified keys. If no keys are specified, then all keys from
284 the configured public keyrings are listed.
286 Never use the output of this command in scripts or other programs.
287 The output is intended only for humans and its format is likely to
288 change. The @option{--with-colons} option emits the output in a
289 stable, machine-parseable format, which is intended for use by scripts
292 @item --list-secret-keys
294 @opindex list-secret-keys
295 List the specified secret keys. If no keys are specified, then all
296 known secret keys are listed. A @code{#} after the letters @code{sec}
297 means that the secret key is not usable (for example, if it was
298 exported using @option{--export-secret-subkeys}). See also
299 @option{--list-keys}.
301 @item --list-signatures
302 @opindex list-signatures
305 Same as @option{--list-keys}, but the signatures are listed too.
306 This command has the same effect as
307 using @option{--list-keys} with @option{--with-sig-list}.
309 For each signature listed, there are several flags in between the "sig"
310 tag and keyid. These flags give additional information about each
311 signature. From left to right, they are the numbers 1-3 for certificate
312 check level (see @option{--ask-cert-level}), "L" for a local or
313 non-exportable signature (see @option{--lsign-key}), "R" for a
314 nonRevocable signature (see the @option{--edit-key} command "nrsign"),
315 "P" for a signature that contains a policy URL (see
316 @option{--cert-policy-url}), "N" for a signature that contains a
317 notation (see @option{--cert-notation}), "X" for an eXpired signature
318 (see @option{--ask-cert-expire}), and the numbers 1-9 or "T" for 10 and
319 above to indicate trust signature levels (see the @option{--edit-key}
322 @item --check-signatures
323 @opindex check-signatures
326 Same as @option{--list-signatures}, but the signatures are verified. Note
327 that for performance reasons the revocation status of a signing key is
329 This command has the same effect as
330 using @option{--list-keys} with @option{--with-sig-check}.
332 The status of the verification is indicated by a flag directly following
333 the "sig" tag (and thus before the flags described above for
334 @option{--list-signatures}). A "!" indicates that the signature has been
335 successfully verified, a "-" denotes a bad signature and a "%" is used
336 if an error occurred while checking the signature (e.g. a non supported
341 Locate the keys given as arguments. This command basically uses the
342 same algorithm as used when locating keys for encryption or signing and
343 may thus be used to see what keys @command{@gpgname} might use. In
344 particular external methods as defined by @option{--auto-key-locate} may
345 be used to locate a key. Only public keys are listed.
349 List all keys (or the specified ones) along with their
350 fingerprints. This is the same output as @option{--list-keys} but with
351 the additional output of a line with the fingerprint. May also be
352 combined with @option{--list-signatures} or @option{--check-signatures}. If this
353 command is given twice, the fingerprints of all secondary keys are
354 listed too. This command also forces pretty printing of fingerprints
355 if the keyid format has been set to "none".
358 @opindex list-packets
359 List only the sequence of packets. This command is only useful for
360 debugging. When used with option @option{--verbose} the actual MPI
361 values are dumped and not only their lengths. Note that the output of
362 this command may change with new releases.
369 Present a menu to work with a smartcard. The subcommand "help" provides
370 an overview on available commands. For a detailed description, please
371 see the Card HOWTO at
372 https://gnupg.org/documentation/howtos.html#GnuPG-cardHOWTO .
376 Show the content of the smart card.
380 Present a menu to allow changing the PIN of a smartcard. This
381 functionality is also available as the subcommand "passwd" with the
382 @option{--edit-card} command.
384 @item --delete-keys @code{name}
385 @itemx --delete-keys @code{name}
386 Remove key from the public keyring. In batch mode either @option{--yes} is
387 required or the key must be specified by fingerprint. This is a
388 safeguard against accidental deletion of multiple keys.
390 @item --delete-secret-keys @code{name}
391 @opindex delete-secret-keys
392 Remove key from the secret keyring. In batch mode the key must be
393 specified by fingerprint. The option @option{--yes} can be used to
394 advice gpg-agent not to request a confirmation. This extra
395 pre-caution is done because @command{@gpgname} can't be sure that the
396 secret key (as controlled by gpg-agent) is only used for the given
400 @item --delete-secret-and-public-key @code{name}
401 @opindex delete-secret-and-public-key
402 Same as @option{--delete-key}, but if a secret key exists, it will be
403 removed first. In batch mode the key must be specified by fingerprint.
404 The option @option{--yes} can be used to advice gpg-agent not to
405 request a confirmation.
409 Either export all keys from all keyrings (default keyrings and those
410 registered via option @option{--keyring}), or if at least one name is given,
411 those of the given name. The exported keys are written to STDOUT or to the
412 file given with option @option{--output}. Use together with
413 @option{--armor} to mail those keys.
415 @item --send-keys @code{key IDs}
417 Similar to @option{--export} but sends the keys to a keyserver.
418 Fingerprints may be used instead of key IDs. Option @option{--keyserver}
419 must be used to give the name of this keyserver. Don't send your
420 complete keyring to a keyserver --- select only those keys which are new
421 or changed by you. If no key IDs are given, @command{@gpgname} does nothing.
423 @item --export-secret-keys
424 @itemx --export-secret-subkeys
425 @opindex export-secret-keys
426 @opindex export-secret-subkeys
427 Same as @option{--export}, but exports the secret keys instead. The
428 exported keys are written to STDOUT or to the file given with option
429 @option{--output}. This command is often used along with the option
430 @option{--armor} to allow for easy printing of the key for paper backup;
431 however the external tool @command{paperkey} does a better job of
432 creating backups on paper. Note that exporting a secret key can be a
433 security risk if the exported keys are sent over an insecure channel.
435 The second form of the command has the special property to render the
436 secret part of the primary key useless; this is a GNU extension to
437 OpenPGP and other implementations can not be expected to successfully
438 import such a key. Its intended use is in generating a full key with
439 an additional signing subkey on a dedicated machine. This command
440 then exports the key without the primary key to the main machine.
442 GnuPG may ask you to enter the passphrase for the key. This is
443 required, because the internal protection method of the secret key is
444 different from the one specified by the OpenPGP protocol.
446 @item --export-ssh-key
447 @opindex export-ssh-key
448 This command is used to export a key in the OpenSSH public key format.
449 It requires the specification of one key by the usual means and
450 exports the latest valid subkey which has an authentication capability
451 to STDOUT or to the file given with option @option{--output}. That
452 output can directly be added to ssh's @file{authorized_key} file.
454 By specifying the key to export using a key ID or a fingerprint
455 suffixed with an exclamation mark (!), a specific subkey or the
456 primary key can be exported. This does not even require that the key
457 has the authentication capability flag set.
462 Import/merge keys. This adds the given keys to the
463 keyring. The fast version is currently just a synonym.
465 There are a few other options which control how this command works.
466 Most notable here is the @option{--import-options merge-only} option
467 which does not insert new keys but does only the merging of new
468 signatures, user-IDs and subkeys.
470 @item --receive-keys @code{key IDs}
471 @opindex receive-keys
472 @itemx --recv-keys @code{key IDs}
474 Import the keys with the given key IDs from a keyserver. Option
475 @option{--keyserver} must be used to give the name of this keyserver.
478 @opindex refresh-keys
479 Request updates from a keyserver for keys that already exist on the
480 local keyring. This is useful for updating a key with the latest
481 signatures, user IDs, etc. Calling this with no arguments will refresh
482 the entire keyring. Option @option{--keyserver} must be used to give the
483 name of the keyserver for all keys that do not have preferred keyservers
484 set (see @option{--keyserver-options honor-keyserver-url}).
486 @item --search-keys @code{names}
488 Search the keyserver for the given names. Multiple names given here will
489 be joined together to create the search string for the keyserver.
490 Option @option{--keyserver} must be used to give the name of this
491 keyserver. Keyservers that support different search methods allow using
492 the syntax specified in "How to specify a user ID" below. Note that
493 different keyserver types support different search methods. Currently
494 only LDAP supports them all.
496 @item --fetch-keys @code{URIs}
498 Retrieve keys located at the specified URIs. Note that different
499 installations of GnuPG may support different protocols (HTTP, FTP,
500 LDAP, etc.). When using HTTPS the system provided root certificates
501 are used by this command.
503 @item --update-trustdb
504 @opindex update-trustdb
505 Do trust database maintenance. This command iterates over all keys and
506 builds the Web of Trust. This is an interactive command because it may
507 have to ask for the "ownertrust" values for keys. The user has to give
508 an estimation of how far she trusts the owner of the displayed key to
509 correctly certify (sign) other keys. GnuPG only asks for the ownertrust
510 value if it has not yet been assigned to a key. Using the
511 @option{--edit-key} menu, the assigned value can be changed at any time.
513 @item --check-trustdb
514 @opindex check-trustdb
515 Do trust database maintenance without user interaction. From time to
516 time the trust database must be updated so that expired keys or
517 signatures and the resulting changes in the Web of Trust can be
518 tracked. Normally, GnuPG will calculate when this is required and do it
519 automatically unless @option{--no-auto-check-trustdb} is set. This
520 command can be used to force a trust database check at any time. The
521 processing is identical to that of @option{--update-trustdb} but it
522 skips keys with a not yet defined "ownertrust".
524 For use with cron jobs, this command can be used together with
525 @option{--batch} in which case the trust database check is done only if
526 a check is needed. To force a run even in batch mode add the option
529 @anchor{option --export-ownertrust}
530 @item --export-ownertrust
531 @opindex export-ownertrust
532 Send the ownertrust values to STDOUT. This is useful for backup purposes
533 as these values are the only ones which can't be re-created from a
534 corrupted trustdb. Example:
537 @gpgname{} --export-ownertrust > otrust.txt
542 @item --import-ownertrust
543 @opindex import-ownertrust
544 Update the trustdb with the ownertrust values stored in @code{files} (or
545 STDIN if not given); existing values will be overwritten. In case of a
546 severely damaged trustdb and if you have a recent backup of the
547 ownertrust values (e.g. in the file @file{otrust.txt}), you may re-create
548 the trustdb using these commands:
553 @gpgname{} --import-ownertrust < otrust.txt
558 @item --rebuild-keydb-caches
559 @opindex rebuild-keydb-caches
560 When updating from version 1.0.6 to 1.0.7 this command should be used
561 to create signature caches in the keyring. It might be handy in other
564 @item --print-md @code{algo}
567 Print message digest of algorithm ALGO for all given files or STDIN.
568 With the second form (or a deprecated "*" as algo) digests for all
569 available algorithms are printed.
571 @item --gen-random @code{0|1|2} @code{count}
573 Emit @var{count} random bytes of the given quality level 0, 1 or 2. If
574 @var{count} is not given or zero, an endless sequence of random bytes
575 will be emitted. If used with @option{--armor} the output will be
576 base64 encoded. PLEASE, don't use this command unless you know what
577 you are doing; it may remove precious entropy from the system!
579 @item --gen-prime @code{mode} @code{bits}
581 Use the source, Luke :-). The output format is still subject to change.
588 Pack or unpack an arbitrary input into/from an OpenPGP ASCII armor.
589 This is a GnuPG extension to OpenPGP and in general not very useful.
591 @item --tofu-policy @code{auto|good|unknown|bad|ask} @code{key...}
593 Set the TOFU policy for all the bindings associated with the specified
594 keys. For more information about the meaning of the policies,
595 @pxref{trust-model-tofu}. The keys may be specified either by their
596 fingerprint (preferred) or their keyid.
600 @c Run gpg in server mode. This feature is not yet ready for use and
601 @c thus not documented.
606 @c *******************************************
607 @c ******* KEY MANGEMENT COMMANDS **********
608 @c *******************************************
609 @node OpenPGP Key Management
610 @subsection How to manage your keys
612 This section explains the main commands for key management.
616 @item --quick-generate-key @code{user-id} [@code{algo} [@code{usage} [@code{expire}]]]
617 @opindex quick-generate-key
618 This is a simple command to generate a standard key with one user id.
619 In contrast to @option{--generate-key} the key is generated directly
620 without the need to answer a bunch of prompts. Unless the option
621 @option{--yes} is given, the key creation will be canceled if the
622 given user id already exists in the keyring.
624 If invoked directly on the console without any special options an
625 answer to a ``Continue?'' style confirmation prompt is required. In
626 case the user id already exists in the keyring a second prompt to
627 force the creation of the key will show up.
629 If @code{algo} or @code{usage} are given, only the primary key is
630 created and no prompts are shown. To specify an expiration date but
631 still create a primary and subkey use ``default'' or
632 ``future-default'' for @code{algo} and ``default'' for @code{usage}.
633 For a description of these optional arguments see the command
634 @code{--quick-add-key}. The @code{usage} accepts also the value
635 ``cert'' which can be used to create a certification only primary key;
636 the default is to a create certification and signing key.
638 The @code{expire} argument can be used to specify an expiration date
639 for the key. Several formats are supported; commonly the ISO
640 YYYY-MM-DD format is used. The values ``never'', ``none'' can be used
641 for no expiration date. Not specifying a value, or using ``-''
642 results in a key expiring in a reasonable default interval.
644 If this command is used with @option{--batch},
645 @option{--pinentry-mode} has been set to @code{loopback}, and one of
646 the passphrase options (@option{--passphrase},
647 @option{--passphrase-fd}, or @option{passphrase-file}) is used, the
648 supplied passphrase is used for the new key and the agent does not ask
649 for it. To create a key without any protection @code{--passphrase ''}
652 @item --quick-set-expire @code{fpr} @code{expire}
653 @opindex quick-set-expire
654 Directly set the expiration time of the primary key to @code{expire}.
655 To remove the expiration time @code{0} can be used.
658 @item --quick-add-key @code{fpr} [@code{algo} [@code{usage} [@code{expire}]]]
659 @opindex quick-add-key
660 Directly add a subkey to the key identified by the fingerprint
661 @code{fpr}. Without the optional arguments an encryption subkey is
662 added. If any of the arguments are given a more specific subkey is
665 @code{algo} may be any of the supported algorithms or curve names
666 given in the format as used by key listings. To use the default
667 algorithm the string ``default'' or ``-'' can be used. Supported
668 algorithms are ``rsa'', ``dsa'', ``elg'', ``ed25519'', ``cv25519'',
669 and other ECC curves. For example the string ``rsa'' adds an RSA key
670 with the default key length; a string ``rsa4096'' requests that the
671 key length is 4096 bits. The string ``future-default'' is an alias
672 for the algorithm which will likely be used as default algorithm in
673 future versions of gpg.
675 Depending on the given @code{algo} the subkey may either be an
676 encryption subkey or a signing subkey. If an algorithm is capable of
677 signing and encryption and such a subkey is desired, a @code{usage}
678 string must be given. This string is either ``default'' or ``-'' to
679 keep the default or a comma delimited list of keywords: ``sign'' for a
680 signing subkey, ``auth'' for an authentication subkey, and ``encr''
681 for an encryption subkey (``encrypt'' can be used as alias for
682 ``encr''). The valid combinations depend on the algorithm.
684 The @code{expire} argument can be used to specify an expiration date
685 for the subkey. Several formats are supported; commonly the ISO
686 YYYY-MM-DD format is used. The values ``never'', ``none'', or ``-''
687 can be used for no expiration date.
690 @opindex generate-key
693 Generate a new key pair using the current default parameters. This is
694 the standard command to create a new key. In addition to the key a
695 revocation certificate is created and stored in the
696 @file{openpgp-revocs.d} directory below the GnuPG home directory.
698 @item --full-generate-key
699 @opindex full-generate-key
700 @itemx --full-gen-key
701 @opindex full-gen-key
702 Generate a new key pair with dialogs for all options. This is an
703 extended version of @option{--generate-key}.
705 There is also a feature which allows you to create keys in batch
706 mode. See the manual section ``Unattended key generation'' on how
710 @item --generate-revocation @code{name}
711 @opindex generate-revocation
712 @itemx --gen-revoke @code{name}
714 Generate a revocation certificate for the complete key. To only revoke
715 a subkey or a key signature, use the @option{--edit} command.
717 This command merely creates the revocation certificate so that it can
718 be used to revoke the key if that is ever needed. To actually revoke
719 a key the created revocation certificate needs to be merged with the
720 key to revoke. This is done by importing the revocation certificate
721 using the @option{--import} command. Then the revoked key needs to be
722 published, which is best done by sending the key to a keyserver
723 (command @option{--send-key}) and by exporting (@option{--export}) it
724 to a file which is then send to frequent communication partners.
727 @item --generate-designated-revocation @code{name}
728 @opindex generate-designated-revocation
729 @itemx --desig-revoke @code{name}
730 @opindex desig-revoke
731 Generate a designated revocation certificate for a key. This allows a
732 user (with the permission of the keyholder) to revoke someone else's
738 Present a menu which enables you to do most of the key management
739 related tasks. It expects the specification of a key on the command
742 @c ******** Begin Edit-key Options **********
747 Toggle selection of user ID or photographic user ID with index @code{n}.
748 Use @code{*} to select all and @code{0} to deselect all.
752 Toggle selection of subkey with index @code{n} or key ID @code{n}.
753 Use @code{*} to select all and @code{0} to deselect all.
756 @opindex keyedit:sign
757 Make a signature on key of user @code{name}. If the key is not yet
758 signed by the default user (or the users given with @option{-u}), the program
759 displays the information of the key again, together with its
760 fingerprint and asks whether it should be signed. This question is
761 repeated for all users specified with
765 @opindex keyedit:lsign
766 Same as "sign" but the signature is marked as non-exportable and will
767 therefore never be used by others. This may be used to make keys
768 valid only in the local environment.
771 @opindex keyedit:nrsign
772 Same as "sign" but the signature is marked as non-revocable and can
773 therefore never be revoked.
776 @opindex keyedit:tsign
777 Make a trust signature. This is a signature that combines the notions
778 of certification (like a regular signature), and trust (like the
779 "trust" command). It is generally only useful in distinct communities
780 or groups. For more information please read the sections
781 ``Trust Signature'' and ``Regular Expression'' in RFC-4880.
785 Note that "l" (for local / non-exportable), "nr" (for non-revocable,
786 and "t" (for trust) may be freely mixed and prefixed to "sign" to
787 create a signature of any type desired.
790 If the option @option{--only-sign-text-ids} is specified, then any
791 non-text based user ids (e.g., photo IDs) will not be selected for
797 @opindex keyedit:delsig
798 Delete a signature. Note that it is not possible to retract a signature,
799 once it has been send to the public (i.e. to a keyserver). In that case
800 you better use @code{revsig}.
803 @opindex keyedit:revsig
804 Revoke a signature. For every signature which has been generated by
805 one of the secret keys, GnuPG asks whether a revocation certificate
809 @opindex keyedit:check
810 Check the signatures on all selected user IDs. With the extra
811 option @code{selfsig} only self-signatures are shown.
814 @opindex keyedit:adduid
815 Create an additional user ID.
818 @opindex keyedit:addphoto
819 Create a photographic user ID. This will prompt for a JPEG file that
820 will be embedded into the user ID. Note that a very large JPEG will make
821 for a very large key. Also note that some programs will display your
822 JPEG unchanged (GnuPG), and some programs will scale it to fit in a
826 @opindex keyedit:showphoto
827 Display the selected photographic user ID.
830 @opindex keyedit:deluid
831 Delete a user ID or photographic user ID. Note that it is not
832 possible to retract a user id, once it has been send to the public
833 (i.e. to a keyserver). In that case you better use @code{revuid}.
836 @opindex keyedit:revuid
837 Revoke a user ID or photographic user ID.
840 @opindex keyedit:primary
841 Flag the current user id as the primary one, removes the primary user
842 id flag from all other user ids and sets the timestamp of all affected
843 self-signatures one second ahead. Note that setting a photo user ID
844 as primary makes it primary over other photo user IDs, and setting a
845 regular user ID as primary makes it primary over other regular user
849 @opindex keyedit:keyserver
850 Set a preferred keyserver for the specified user ID(s). This allows
851 other users to know where you prefer they get your key from. See
852 @option{--keyserver-options honor-keyserver-url} for more on how this
853 works. Setting a value of "none" removes an existing preferred
857 @opindex keyedit:notation
858 Set a name=value notation for the specified user ID(s). See
859 @option{--cert-notation} for more on how this works. Setting a value of
860 "none" removes all notations, setting a notation prefixed with a minus
861 sign (-) removes that notation, and setting a notation name (without the
862 =value) prefixed with a minus sign removes all notations with that name.
865 @opindex keyedit:pref
866 List preferences from the selected user ID. This shows the actual
867 preferences, without including any implied preferences.
870 @opindex keyedit:showpref
871 More verbose preferences listing for the selected user ID. This shows
872 the preferences in effect by including the implied preferences of 3DES
873 (cipher), SHA-1 (digest), and Uncompressed (compression) if they are
874 not already included in the preference list. In addition, the
875 preferred keyserver and signature notations (if any) are shown.
877 @item setpref @code{string}
878 @opindex keyedit:setpref
879 Set the list of user ID preferences to @code{string} for all (or just
880 the selected) user IDs. Calling setpref with no arguments sets the
881 preference list to the default (either built-in or set via
882 @option{--default-preference-list}), and calling setpref with "none"
883 as the argument sets an empty preference list. Use @command{@gpgname
884 --version} to get a list of available algorithms. Note that while you
885 can change the preferences on an attribute user ID (aka "photo ID"),
886 GnuPG does not select keys via attribute user IDs so these preferences
887 will not be used by GnuPG.
889 When setting preferences, you should list the algorithms in the order
890 which you'd like to see them used by someone else when encrypting a
891 message to your key. If you don't include 3DES, it will be
892 automatically added at the end. Note that there are many factors that
893 go into choosing an algorithm (for example, your key may not be the
894 only recipient), and so the remote OpenPGP application being used to
895 send to you may or may not follow your exact chosen order for a given
896 message. It will, however, only choose an algorithm that is present
897 on the preference list of every recipient key. See also the
898 INTEROPERABILITY WITH OTHER OPENPGP PROGRAMS section below.
901 @opindex keyedit:addkey
902 Add a subkey to this key.
905 @opindex keyedit:addcardkey
906 Generate a subkey on a card and add it to this key.
909 @opindex keyedit:keytocard
910 Transfer the selected secret subkey (or the primary key if no subkey
911 has been selected) to a smartcard. The secret key in the keyring will
912 be replaced by a stub if the key could be stored successfully on the
913 card and you use the save command later. Only certain key types may be
914 transferred to the card. A sub menu allows you to select on what card
915 to store the key. Note that it is not possible to get that key back
916 from the card - if the card gets broken your secret key will be lost
917 unless you have a backup somewhere.
919 @item bkuptocard @code{file}
920 @opindex keyedit:bkuptocard
921 Restore the given file to a card. This command may be used to restore a
922 backup key (as generated during card initialization) to a new card. In
923 almost all cases this will be the encryption key. You should use this
924 command only with the corresponding public key and make sure that the
925 file given as argument is indeed the backup to restore. You should then
926 select 2 to restore as encryption key. You will first be asked to enter
927 the passphrase of the backup key and then for the Admin PIN of the card.
930 @opindex keyedit:delkey
931 Remove a subkey (secondary key). Note that it is not possible to retract
932 a subkey, once it has been send to the public (i.e. to a keyserver). In
933 that case you better use @code{revkey}. Also note that this only
934 deletes the public part of a key.
937 @opindex keyedit:revkey
941 @opindex keyedit:expire
942 Change the key or subkey expiration time. If a subkey is selected, the
943 expiration time of this subkey will be changed. With no selection, the
944 key expiration of the primary key is changed.
947 @opindex keyedit:trust
948 Change the owner trust value for the key. This updates the trust-db
949 immediately and no save is required.
953 @opindex keyedit:disable
954 @opindex keyedit:enable
955 Disable or enable an entire key. A disabled key can not normally be
959 @opindex keyedit:addrevoker
960 Add a designated revoker to the key. This takes one optional argument:
961 "sensitive". If a designated revoker is marked as sensitive, it will
962 not be exported by default (see export-options).
965 @opindex keyedit:passwd
966 Change the passphrase of the secret key.
969 @opindex keyedit:toggle
970 This is dummy command which exists only for backward compatibility.
973 @opindex keyedit:clean
974 Compact (by removing all signatures except the selfsig) any user ID
975 that is no longer usable (e.g. revoked, or expired). Then, remove any
976 signatures that are not usable by the trust calculations.
977 Specifically, this removes any signature that does not validate, any
978 signature that is superseded by a later signature, revoked signatures,
979 and signatures issued by keys that are not present on the keyring.
982 @opindex keyedit:minimize
983 Make the key as small as possible. This removes all signatures from
984 each user ID except for the most recent self-signature.
987 @opindex keyedit:cross-certify
988 Add cross-certification signatures to signing subkeys that may not
989 currently have them. Cross-certification signatures protect against a
990 subtle attack against signing subkeys. See
991 @option{--require-cross-certification}. All new keys generated have
992 this signature by default, so this command is only useful to bring
993 older keys up to date.
996 @opindex keyedit:save
997 Save all changes to the keyrings and quit.
1000 @opindex keyedit:quit
1001 Quit the program without updating the
1006 The listing shows you the key with its secondary keys and all user
1007 ids. The primary user id is indicated by a dot, and selected keys or
1008 user ids are indicated by an asterisk. The trust
1009 value is displayed with the primary key: the first is the assigned owner
1010 trust and the second is the calculated trust value. Letters are used for
1017 No ownertrust assigned / not yet calculated.
1021 calculation has failed; probably due to an expired key.
1024 Not enough information for calculation.
1027 Never trust this key.
1039 @c ******** End Edit-key Options **********
1041 @item --sign-key @code{name}
1043 Signs a public key with your secret key. This is a shortcut version of
1044 the subcommand "sign" from @option{--edit}.
1046 @item --lsign-key @code{name}
1048 Signs a public key with your secret key but marks it as
1049 non-exportable. This is a shortcut version of the subcommand "lsign"
1050 from @option{--edit-key}.
1052 @item --quick-sign-key @code{fpr} [@code{names}]
1053 @itemx --quick-lsign-key @code{fpr} [@code{names}]
1054 @opindex quick-sign-key
1055 @opindex quick-lsign-key
1056 Directly sign a key from the passphrase without any further user
1057 interaction. The @code{fpr} must be the verified primary fingerprint
1058 of a key in the local keyring. If no @code{names} are given, all
1059 useful user ids are signed; with given [@code{names}] only useful user
1060 ids matching one of theses names are signed. By default, or if a name
1061 is prefixed with a '*', a case insensitive substring match is used.
1062 If a name is prefixed with a '=' a case sensitive exact match is done.
1064 The command @option{--quick-lsign-key} marks the signatures as
1065 non-exportable. If such a non-exportable signature already exists the
1066 @option{--quick-sign-key} turns it into a exportable signature.
1068 This command uses reasonable defaults and thus does not provide the
1069 full flexibility of the "sign" subcommand from @option{--edit-key}.
1070 Its intended use is to help unattended key signing by utilizing a list
1071 of verified fingerprints.
1073 @item --quick-add-uid @var{user-id} @var{new-user-id}
1074 @opindex quick-add-uid
1075 This command adds a new user id to an existing key. In contrast to
1076 the interactive sub-command @code{adduid} of @option{--edit-key} the
1077 @var{new-user-id} is added verbatim with only leading and trailing
1078 white space removed, it is expected to be UTF-8 encoded, and no checks
1079 on its form are applied.
1081 @item --quick-revoke-uid @var{user-id} @var{user-id-to-revoke}
1082 @opindex quick-revoke-uid
1083 This command revokes a User ID on an existing key. It cannot be used
1084 to revoke the last User ID on key (some non-revoked User ID must
1085 remain), with revocation reason ``User ID is no longer valid''. If
1086 you want to specify a different revocation reason, or to supply
1087 supplementary revocation text, you should use the interactive
1088 sub-command @code{revuid} of @option{--edit-key}.
1090 @item --change-passphrase @var{user_id}
1091 @opindex change-passphrase
1092 @itemx --passwd @var{user_id}
1094 Change the passphrase of the secret key belonging to the certificate
1095 specified as @var{user_id}. This is a shortcut for the sub-command
1096 @code{passwd} of the edit key menu.
1101 @c *******************************************
1102 @c *************** ****************
1103 @c *************** OPTIONS ****************
1104 @c *************** ****************
1105 @c *******************************************
1108 @section Option Summary
1110 @command{@gpgname} features a bunch of options to control the exact
1111 behaviour and to change the default configuration.
1114 * GPG Configuration Options:: How to change the configuration.
1115 * GPG Key related Options:: Key related options.
1116 * GPG Input and Output:: Input and Output.
1117 * OpenPGP Options:: OpenPGP protocol specific options.
1118 * Compliance Options:: Compliance options.
1119 * GPG Esoteric Options:: Doing things one usually doesn't want to do.
1120 * Deprecated Options:: Deprecated options.
1123 Long options can be put in an options file (default
1124 "~/.gnupg/gpg.conf"). Short option names will not work - for example,
1125 "armor" is a valid option for the options file, while "a" is not. Do not
1126 write the 2 dashes, but simply the name of the option and any required
1127 arguments. Lines with a hash ('#') as the first non-white-space
1128 character are ignored. Commands may be put in this file too, but that is
1129 not generally useful as the command will execute automatically with
1130 every execution of gpg.
1132 Please remember that option parsing stops as soon as a non-option is
1133 encountered, you can explicitly stop parsing by using the special option
1136 @c *******************************************
1137 @c ******** CONFIGURATION OPTIONS **********
1138 @c *******************************************
1139 @node GPG Configuration Options
1140 @subsection How to change the configuration
1142 These options are used to change the configuration and are usually found
1147 @item --default-key @var{name}
1148 @opindex default-key
1149 Use @var{name} as the default key to sign with. If this option is not
1150 used, the default key is the first key found in the secret keyring.
1151 Note that @option{-u} or @option{--local-user} overrides this option.
1152 This option may be given multiple times. In this case, the last key
1153 for which a secret key is available is used. If there is no secret
1154 key available for any of the specified values, GnuPG will not emit an
1155 error message but continue as if this option wasn't given.
1157 @item --default-recipient @var{name}
1158 @opindex default-recipient
1159 Use @var{name} as default recipient if option @option{--recipient} is
1160 not used and don't ask if this is a valid one. @var{name} must be
1163 @item --default-recipient-self
1164 @opindex default-recipient-self
1165 Use the default key as default recipient if option @option{--recipient} is not
1166 used and don't ask if this is a valid one. The default key is the first
1167 one from the secret keyring or the one set with @option{--default-key}.
1169 @item --no-default-recipient
1170 @opindex no-default-recipient
1171 Reset @option{--default-recipient} and @option{--default-recipient-self}.
1175 Give more information during processing. If used
1176 twice, the input data is listed in detail.
1180 Reset verbose level to 0.
1184 Try to be as quiet as possible.
1190 Use batch mode. Never ask, do not allow interactive commands.
1191 @option{--no-batch} disables this option. Note that even with a
1192 filename given on the command line, gpg might still need to read from
1193 STDIN (in particular if gpg figures that the input is a
1194 detached signature and no data file has been specified). Thus if you
1195 do not want to feed data via STDIN, you should connect STDIN to
1198 It is highly recommended to use this option along with the options
1199 @option{--status-fd} and @option{--with-colons} for any unattended of
1204 Make sure that the TTY (terminal) is never used for any output.
1205 This option is needed in some cases because GnuPG sometimes prints
1206 warnings to the TTY even if @option{--batch} is used.
1210 Assume "yes" on most questions.
1214 Assume "no" on most questions.
1217 @item --list-options @code{parameters}
1218 @opindex list-options
1219 This is a space or comma delimited string that gives options used when
1220 listing keys and signatures (that is, @option{--list-keys},
1221 @option{--list-signatures}, @option{--list-public-keys},
1222 @option{--list-secret-keys}, and the @option{--edit-key} functions).
1223 Options can be prepended with a @option{no-} (after the two dashes) to
1224 give the opposite meaning. The options are:
1229 @opindex list-options:show-photos
1230 Causes @option{--list-keys}, @option{--list-signatures},
1231 @option{--list-public-keys}, and @option{--list-secret-keys} to
1232 display any photo IDs attached to the key. Defaults to no. See also
1233 @option{--photo-viewer}. Does not work with @option{--with-colons}:
1234 see @option{--attribute-fd} for the appropriate way to get photo data
1235 for scripts and other frontends.
1238 @opindex list-options:show-usage
1239 Show usage information for keys and subkeys in the standard key
1240 listing. This is a list of letters indicating the allowed usage for a
1241 key (@code{E}=encryption, @code{S}=signing, @code{C}=certification,
1242 @code{A}=authentication). Defaults to yes.
1244 @item show-policy-urls
1245 @opindex list-options:show-policy-urls
1246 Show policy URLs in the @option{--list-signatures} or @option{--check-signatures}
1247 listings. Defaults to no.
1249 @item show-notations
1250 @itemx show-std-notations
1251 @itemx show-user-notations
1252 @opindex list-options:show-notations
1253 @opindex list-options:show-std-notations
1254 @opindex list-options:show-user-notations
1255 Show all, IETF standard, or user-defined signature notations in the
1256 @option{--list-signatures} or @option{--check-signatures} listings. Defaults to no.
1258 @item show-keyserver-urls
1259 @opindex list-options:show-keyserver-urls
1260 Show any preferred keyserver URL in the @option{--list-signatures} or
1261 @option{--check-signatures} listings. Defaults to no.
1263 @item show-uid-validity
1264 @opindex list-options:show-uid-validity
1265 Display the calculated validity of user IDs during key listings.
1268 @item show-unusable-uids
1269 @opindex list-options:show-unusable-uids
1270 Show revoked and expired user IDs in key listings. Defaults to no.
1272 @item show-unusable-subkeys
1273 @opindex list-options:show-unusable-subkeys
1274 Show revoked and expired subkeys in key listings. Defaults to no.
1277 @opindex list-options:show-keyring
1278 Display the keyring name at the head of key listings to show which
1279 keyring a given key resides on. Defaults to no.
1281 @item show-sig-expire
1282 @opindex list-options:show-sig-expire
1283 Show signature expiration dates (if any) during @option{--list-signatures} or
1284 @option{--check-signatures} listings. Defaults to no.
1286 @item show-sig-subpackets
1287 @opindex list-options:show-sig-subpackets
1288 Include signature subpackets in the key listing. This option can take an
1289 optional argument list of the subpackets to list. If no argument is
1290 passed, list all subpackets. Defaults to no. This option is only
1291 meaningful when using @option{--with-colons} along with
1292 @option{--list-signatures} or @option{--check-signatures}.
1296 @item --verify-options @code{parameters}
1297 @opindex verify-options
1298 This is a space or comma delimited string that gives options used when
1299 verifying signatures. Options can be prepended with a `no-' to give
1300 the opposite meaning. The options are:
1305 @opindex verify-options:show-photos
1306 Display any photo IDs present on the key that issued the signature.
1307 Defaults to no. See also @option{--photo-viewer}.
1309 @item show-policy-urls
1310 @opindex verify-options:show-policy-urls
1311 Show policy URLs in the signature being verified. Defaults to yes.
1313 @item show-notations
1314 @itemx show-std-notations
1315 @itemx show-user-notations
1316 @opindex verify-options:show-notations
1317 @opindex verify-options:show-std-notations
1318 @opindex verify-options:show-user-notations
1319 Show all, IETF standard, or user-defined signature notations in the
1320 signature being verified. Defaults to IETF standard.
1322 @item show-keyserver-urls
1323 @opindex verify-options:show-keyserver-urls
1324 Show any preferred keyserver URL in the signature being verified.
1327 @item show-uid-validity
1328 @opindex verify-options:show-uid-validity
1329 Display the calculated validity of the user IDs on the key that issued
1330 the signature. Defaults to yes.
1332 @item show-unusable-uids
1333 @opindex verify-options:show-unusable-uids
1334 Show revoked and expired user IDs during signature verification.
1337 @item show-primary-uid-only
1338 @opindex verify-options:show-primary-uid-only
1339 Show only the primary user ID during signature verification. That is
1340 all the AKA lines as well as photo Ids are not shown with the signature
1341 verification status.
1344 @opindex verify-options:pka-lookups
1345 Enable PKA lookups to verify sender addresses. Note that PKA is based
1346 on DNS, and so enabling this option may disclose information on when
1347 and what signatures are verified or to whom data is encrypted. This
1348 is similar to the "web bug" described for the @option{--auto-key-retrieve}
1351 @item pka-trust-increase
1352 @opindex verify-options:pka-trust-increase
1353 Raise the trust in a signature to full if the signature passes PKA
1354 validation. This option is only meaningful if pka-lookups is set.
1357 @item --enable-large-rsa
1358 @itemx --disable-large-rsa
1359 @opindex enable-large-rsa
1360 @opindex disable-large-rsa
1361 With --generate-key and --batch, enable the creation of RSA secret keys as
1362 large as 8192 bit. Note: 8192 bit is more than is generally
1363 recommended. These large keys don't significantly improve security,
1364 but they are more expensive to use, and their signatures and
1365 certifications are larger. This option is only available if the
1366 binary was build with large-secmem support.
1369 @itemx --disable-dsa2
1370 @opindex enable-dsa2
1371 @opindex disable-dsa2
1372 Enable hash truncation for all DSA keys even for old DSA Keys up to
1373 1024 bit. This is also the default with @option{--openpgp}. Note
1374 that older versions of GnuPG also required this flag to allow the
1375 generation of DSA larger than 1024 bit.
1377 @item --photo-viewer @code{string}
1378 @opindex photo-viewer
1379 This is the command line that should be run to view a photo ID. "%i"
1380 will be expanded to a filename containing the photo. "%I" does the
1381 same, except the file will not be deleted once the viewer exits.
1382 Other flags are "%k" for the key ID, "%K" for the long key ID, "%f"
1383 for the key fingerprint, "%t" for the extension of the image type
1384 (e.g. "jpg"), "%T" for the MIME type of the image (e.g. "image/jpeg"),
1385 "%v" for the single-character calculated validity of the image being
1386 viewed (e.g. "f"), "%V" for the calculated validity as a string (e.g.
1387 "full"), "%U" for a base32 encoded hash of the user ID,
1388 and "%%" for an actual percent sign. If neither %i or %I are present,
1389 then the photo will be supplied to the viewer on standard input.
1391 The default viewer is "xloadimage -fork -quiet -title 'KeyID 0x%k'
1392 STDIN". Note that if your image viewer program is not secure, then
1393 executing it from GnuPG does not make it secure.
1395 @item --exec-path @code{string}
1398 Sets a list of directories to search for photo viewers and keyserver
1399 helpers. If not provided, keyserver helpers use the compiled-in
1400 default directory, and photo viewers use the @code{PATH} environment
1402 Note, that on W32 system this value is ignored when searching for
1405 @item --keyring @code{file}
1407 Add @code{file} to the current list of keyrings. If @code{file} begins
1408 with a tilde and a slash, these are replaced by the $HOME directory. If
1409 the filename does not contain a slash, it is assumed to be in the GnuPG
1410 home directory ("~/.gnupg" if @option{--homedir} or $GNUPGHOME is not
1413 Note that this adds a keyring to the current list. If the intent is to
1414 use the specified keyring alone, use @option{--keyring} along with
1415 @option{--no-default-keyring}.
1417 If the the option @option{--no-keyring} has been used no keyrings will
1421 @item --secret-keyring @code{file}
1422 @opindex secret-keyring
1423 This is an obsolete option and ignored. All secret keys are stored in
1424 the @file{private-keys-v1.d} directory below the GnuPG home directory.
1426 @item --primary-keyring @code{file}
1427 @opindex primary-keyring
1428 Designate @code{file} as the primary public keyring. This means that
1429 newly imported keys (via @option{--import} or keyserver
1430 @option{--recv-from}) will go to this keyring.
1432 @item --trustdb-name @code{file}
1433 @opindex trustdb-name
1434 Use @code{file} instead of the default trustdb. If @code{file} begins
1435 with a tilde and a slash, these are replaced by the $HOME directory. If
1436 the filename does not contain a slash, it is assumed to be in the GnuPG
1437 home directory (@file{~/.gnupg} if @option{--homedir} or $GNUPGHOME is
1440 @include opt-homedir.texi
1443 @item --display-charset @code{name}
1444 @opindex display-charset
1445 Set the name of the native character set. This is used to convert
1446 some informational strings like user IDs to the proper UTF-8 encoding.
1447 Note that this has nothing to do with the character set of data to be
1448 encrypted or signed; GnuPG does not recode user-supplied data. If
1449 this option is not used, the default character set is determined from
1450 the current locale. A verbosity level of 3 shows the chosen set.
1451 Valid values for @code{name} are:
1456 @opindex display-charset:iso-8859-1
1457 This is the Latin 1 set.
1460 @opindex display-charset:iso-8859-2
1464 @opindex display-charset:iso-8859-15
1465 This is currently an alias for
1469 @opindex display-charset:koi8-r
1470 The usual Russian set (RFC-1489).
1473 @opindex display-charset:utf-8
1474 Bypass all translations and assume
1475 that the OS uses native UTF-8 encoding.
1478 @item --utf8-strings
1479 @itemx --no-utf8-strings
1480 @opindex utf8-strings
1481 Assume that command line arguments are given as UTF-8 strings. The
1482 default (@option{--no-utf8-strings}) is to assume that arguments are
1483 encoded in the character set as specified by
1484 @option{--display-charset}. These options affect all following
1485 arguments. Both options may be used multiple times.
1487 @anchor{gpg-option --options}
1488 @item --options @code{file}
1490 Read options from @code{file} and do not try to read them from the
1491 default options file in the homedir (see @option{--homedir}). This
1492 option is ignored if used in an options file.
1496 Shortcut for @option{--options /dev/null}. This option is detected
1497 before an attempt to open an option file. Using this option will also
1498 prevent the creation of a @file{~/.gnupg} homedir.
1501 @itemx --compress-level @code{n}
1502 @itemx --bzip2-compress-level @code{n}
1503 @opindex compress-level
1504 @opindex bzip2-compress-level
1505 Set compression level to @code{n} for the ZIP and ZLIB compression
1506 algorithms. The default is to use the default compression level of zlib
1507 (normally 6). @option{--bzip2-compress-level} sets the compression level
1508 for the BZIP2 compression algorithm (defaulting to 6 as well). This is a
1509 different option from @option{--compress-level} since BZIP2 uses a
1510 significant amount of memory for each additional compression level.
1511 @option{-z} sets both. A value of 0 for @code{n} disables compression.
1513 @item --bzip2-decompress-lowmem
1514 @opindex bzip2-decompress-lowmem
1515 Use a different decompression method for BZIP2 compressed files. This
1516 alternate method uses a bit more than half the memory, but also runs
1517 at half the speed. This is useful under extreme low memory
1518 circumstances when the file was originally compressed at a high
1519 @option{--bzip2-compress-level}.
1522 @item --mangle-dos-filenames
1523 @itemx --no-mangle-dos-filenames
1524 @opindex mangle-dos-filenames
1525 @opindex no-mangle-dos-filenames
1526 Older version of Windows cannot handle filenames with more than one
1527 dot. @option{--mangle-dos-filenames} causes GnuPG to replace (rather
1528 than add to) the extension of an output filename to avoid this
1529 problem. This option is off by default and has no effect on non-Windows
1532 @item --ask-cert-level
1533 @itemx --no-ask-cert-level
1534 @opindex ask-cert-level
1535 When making a key signature, prompt for a certification level. If this
1536 option is not specified, the certification level used is set via
1537 @option{--default-cert-level}. See @option{--default-cert-level} for
1538 information on the specific levels and how they are
1539 used. @option{--no-ask-cert-level} disables this option. This option
1542 @item --default-cert-level @code{n}
1543 @opindex default-cert-level
1544 The default to use for the check level when signing a key.
1546 0 means you make no particular claim as to how carefully you verified
1549 1 means you believe the key is owned by the person who claims to own
1550 it but you could not, or did not verify the key at all. This is
1551 useful for a "persona" verification, where you sign the key of a
1554 2 means you did casual verification of the key. For example, this
1555 could mean that you verified the key fingerprint and checked the
1556 user ID on the key against a photo ID.
1558 3 means you did extensive verification of the key. For example, this
1559 could mean that you verified the key fingerprint with the owner of the
1560 key in person, and that you checked, by means of a hard to forge
1561 document with a photo ID (such as a passport) that the name of the key
1562 owner matches the name in the user ID on the key, and finally that you
1563 verified (by exchange of email) that the email address on the key
1564 belongs to the key owner.
1566 Note that the examples given above for levels 2 and 3 are just that:
1567 examples. In the end, it is up to you to decide just what "casual"
1568 and "extensive" mean to you.
1570 This option defaults to 0 (no particular claim).
1572 @item --min-cert-level
1573 @opindex min-cert-level
1574 When building the trust database, treat any signatures with a
1575 certification level below this as invalid. Defaults to 2, which
1576 disregards level 1 signatures. Note that level 0 "no particular
1577 claim" signatures are always accepted.
1579 @item --trusted-key @code{long key ID}
1580 @opindex trusted-key
1581 Assume that the specified key (which must be given
1582 as a full 8 byte key ID) is as trustworthy as one of
1583 your own secret keys. This option is useful if you
1584 don't want to keep your secret keys (or one of them)
1585 online but still want to be able to check the validity of a given
1586 recipient's or signator's key.
1588 @item --trust-model @code{pgp|classic|tofu|tofu+pgp|direct|always|auto}
1589 @opindex trust-model
1590 Set what trust model GnuPG should follow. The models are:
1595 @opindex trust-mode:pgp
1596 This is the Web of Trust combined with trust signatures as used in PGP
1597 5.x and later. This is the default trust model when creating a new
1601 @opindex trust-mode:classic
1602 This is the standard Web of Trust as introduced by PGP 2.
1605 @opindex trust-mode:tofu
1606 @anchor{trust-model-tofu}
1607 TOFU stands for Trust On First Use. In this trust model, the first
1608 time a key is seen, it is memorized. If later another key is seen
1609 with a user id with the same email address, a warning is displayed
1610 indicating that there is a conflict and that the key might be a
1611 forgery and an attempt at a man-in-the-middle attack.
1613 Because a potential attacker is able to control the email address
1614 and thereby circumvent the conflict detection algorithm by using an
1615 email address that is similar in appearance to a trusted email
1616 address, whenever a message is verified, statistics about the number
1617 of messages signed with the key are shown. In this way, a user can
1618 easily identify attacks using fake keys for regular correspondents.
1620 When compared with the Web of Trust, TOFU offers significantly
1621 weaker security guarantees. In particular, TOFU only helps ensure
1622 consistency (that is, that the binding between a key and email
1623 address doesn't change). A major advantage of TOFU is that it
1624 requires little maintenance to use correctly. To use the web of
1625 trust properly, you need to actively sign keys and mark users as
1626 trusted introducers. This is a time-consuming process and anecdotal
1627 evidence suggests that even security-conscious users rarely take the
1628 time to do this thoroughly and instead rely on an ad-hoc TOFU
1631 In the TOFU model, policies are associated with bindings between
1632 keys and email addresses (which are extracted from user ids and
1633 normalized). There are five policies, which can be set manually
1634 using the @option{--tofu-policy} option. The default policy can be
1635 set using the @option{--tofu-default-policy} option.
1637 The TOFU policies are: @code{auto}, @code{good}, @code{unknown},
1638 @code{bad} and @code{ask}. The @code{auto} policy is used by
1639 default (unless overridden by @option{--tofu-default-policy}) and
1640 marks a binding as marginally trusted. The @code{good},
1641 @code{unknown} and @code{bad} policies mark a binding as fully
1642 trusted, as having unknown trust or as having trust never,
1643 respectively. The @code{unknown} policy is useful for just using
1644 TOFU to detect conflicts, but to never assign positive trust to a
1645 binding. The final policy, @code{ask} prompts the user to indicate
1646 the binding's trust. If batch mode is enabled (or input is
1647 inappropriate in the context), then the user is not prompted and the
1648 @code{undefined} trust level is returned.
1651 @opindex trust-mode:tofu+pgp
1652 This trust model combines TOFU with the Web of Trust. This is done
1653 by computing the trust level for each model and then taking the
1654 maximum trust level where the trust levels are ordered as follows:
1655 @code{unknown < undefined < marginal < fully < ultimate < expired <
1658 By setting @option{--tofu-default-policy=unknown}, this model can be
1659 used to implement the web of trust with TOFU's conflict detection
1660 algorithm, but without its assignment of positive trust values,
1661 which some security-conscious users don't like.
1664 @opindex trust-mode:direct
1665 Key validity is set directly by the user and not calculated via the
1669 @opindex trust-mode:always
1670 Skip key validation and assume that used keys are always fully
1671 valid. You generally won't use this unless you are using some
1672 external validation scheme. This option also suppresses the
1673 "[uncertain]" tag printed with signature checks when there is no
1674 evidence that the user ID is bound to the key. Note that this
1675 trust model still does not allow the use of expired, revoked, or
1679 @opindex trust-mode:auto
1680 Select the trust model depending on whatever the internal trust
1681 database says. This is the default model if such a database already
1685 @item --auto-key-locate @code{parameters}
1686 @itemx --no-auto-key-locate
1687 @opindex auto-key-locate
1688 GnuPG can automatically locate and retrieve keys as needed using this
1689 option. This happens when encrypting to an email address (in the
1690 "user@@example.com" form), and there are no user@@example.com keys on
1691 the local keyring. This option takes any number of the following
1692 mechanisms, in the order they are to be tried:
1697 Locate a key using DNS CERT, as specified in RFC-4398.
1700 Locate a key using DNS PKA.
1703 Locate a key using DANE, as specified
1704 in draft-ietf-dane-openpgpkey-05.txt.
1707 Locate a key using the Web Key Directory protocol.
1708 This is an experimental method and semantics may change.
1711 Using DNS Service Discovery, check the domain in question for any LDAP
1712 keyservers to use. If this fails, attempt to locate the key using the
1713 PGP Universal method of checking @samp{ldap://keys.(thedomain)}.
1716 Locate a key using whatever keyserver is defined using the
1717 @option{--keyserver} option.
1720 In addition, a keyserver URL as used in the @option{--keyserver} option
1721 may be used here to query that particular keyserver.
1724 Locate the key using the local keyrings. This mechanism allows the user to
1725 select the order a local key lookup is done. Thus using
1726 @samp{--auto-key-locate local} is identical to
1727 @option{--no-auto-key-locate}.
1730 This flag disables the standard local key lookup, done before any of the
1731 mechanisms defined by the @option{--auto-key-locate} are tried. The
1732 position of this mechanism in the list does not matter. It is not
1733 required if @code{local} is also used.
1736 Clear all defined mechanisms. This is useful to override
1737 mechanisms given in a config file.
1741 @item --auto-key-retrieve
1742 @itemx --no-auto-key-retrieve
1743 @opindex auto-key-retrieve
1744 @opindex no-auto-key-retrieve
1745 This option enables the automatic retrieving of keys from a keyserver
1746 when verifying signatures made by keys that are not on the local
1749 If the method "wkd" is included in the list of methods given to
1750 @option{auto-key-locate}, the Signer's User ID is part of the
1751 signature, and the option @option{--disable-signer-uid} is not used,
1752 the "wkd" method may also be used to retrieve a key.
1754 Note that this option makes a "web bug" like behavior possible.
1755 Keyserver or Web Key Directory operators can see which keys you
1756 request, so by sending you a message signed by a brand new key (which
1757 you naturally will not have on your local keyring), the operator can
1758 tell both your IP address and the time when you verified the
1761 @item --keyid-format @code{none|short|0xshort|long|0xlong}
1762 @opindex keyid-format
1763 Select how to display key IDs. "none" does not show the key ID at all
1764 but shows the fingerprint in a separate line. "short" is the
1765 traditional 8-character key ID. "long" is the more accurate (but less
1766 convenient) 16-character key ID. Add an "0x" to either to include an
1767 "0x" at the beginning of the key ID, as in 0x99242560. Note that this
1768 option is ignored if the option @option{--with-colons} is used.
1770 @item --keyserver @code{name}
1772 This option is deprecated - please use the @option{--keyserver} in
1773 @file{dirmngr.conf} instead.
1775 Use @code{name} as your keyserver. This is the server that
1776 @option{--receive-keys}, @option{--send-keys}, and @option{--search-keys}
1777 will communicate with to receive keys from, send keys to, and search for
1778 keys on. The format of the @code{name} is a URI:
1779 `scheme:[//]keyservername[:port]' The scheme is the type of keyserver:
1780 "hkp" for the HTTP (or compatible) keyservers, "ldap" for the LDAP
1781 keyservers, or "mailto" for the Graff email keyserver. Note that your
1782 particular installation of GnuPG may have other keyserver types
1783 available as well. Keyserver schemes are case-insensitive. After the
1784 keyserver name, optional keyserver configuration options may be
1785 provided. These are the same as the global @option{--keyserver-options}
1786 from below, but apply only to this particular keyserver.
1788 Most keyservers synchronize with each other, so there is generally no
1789 need to send keys to more than one server. The keyserver
1790 @code{hkp://keys.gnupg.net} uses round robin DNS to give a different
1791 keyserver each time you use it.
1793 @item --keyserver-options @code{name=value}
1794 @opindex keyserver-options
1795 This is a space or comma delimited string that gives options for the
1796 keyserver. Options can be prefixed with a `no-' to give the opposite
1797 meaning. Valid import-options or export-options may be used here as
1798 well to apply to importing (@option{--recv-key}) or exporting
1799 (@option{--send-key}) a key from a keyserver. While not all options
1800 are available for all keyserver types, some common options are:
1804 @item include-revoked
1805 When searching for a key with @option{--search-keys}, include keys that
1806 are marked on the keyserver as revoked. Note that not all keyservers
1807 differentiate between revoked and unrevoked keys, and for such
1808 keyservers this option is meaningless. Note also that most keyservers do
1809 not have cryptographic verification of key revocations, and so turning
1810 this option off may result in skipping keys that are incorrectly marked
1813 @item include-disabled
1814 When searching for a key with @option{--search-keys}, include keys that
1815 are marked on the keyserver as disabled. Note that this option is not
1816 used with HKP keyservers.
1818 @item auto-key-retrieve
1819 This is the same as the option @option{auto-key-retrieve}.
1821 @item honor-keyserver-url
1822 When using @option{--refresh-keys}, if the key in question has a preferred
1823 keyserver URL, then use that preferred keyserver to refresh the key
1824 from. In addition, if auto-key-retrieve is set, and the signature
1825 being verified has a preferred keyserver URL, then use that preferred
1826 keyserver to fetch the key from. Note that this option introduces a
1827 "web bug": The creator of the key can see when the keys is
1828 refreshed. Thus this option is not enabled by default.
1830 @item honor-pka-record
1831 If @option{--auto-key-retrieve} is used, and the signature being
1832 verified has a PKA record, then use the PKA information to fetch
1833 the key. Defaults to "yes".
1835 @item include-subkeys
1836 When receiving a key, include subkeys as potential targets. Note that
1837 this option is not used with HKP keyservers, as they do not support
1838 retrieving keys by subkey id.
1841 Tell the keyserver helper program how long (in seconds) to try and
1842 perform a keyserver action before giving up. Note that performing
1843 multiple actions at the same time uses this timeout value per action.
1844 For example, when retrieving multiple keys via @option{--receive-keys}, the
1845 timeout applies separately to each key retrieval, and not to the
1846 @option{--receive-keys} command as a whole. Defaults to 30 seconds.
1848 @item http-proxy=@code{value}
1849 This option is deprecated.
1850 Set the proxy to use for HTTP and HKP keyservers.
1851 This overrides any proxy defined in @file{dirmngr.conf}.
1854 This option has no more function since GnuPG 2.1. Use the
1855 @code{dirmngr} configuration options instead.
1858 This option has no more function since GnuPG 2.1. Use the
1859 @code{dirmngr} configuration options instead.
1862 This option has no more function since GnuPG 2.1. Use the
1863 @code{dirmngr} configuration options instead.
1866 This option has no more function since GnuPG 2.1. Use the
1867 @code{dirmngr} configuration options instead.
1871 @item --completes-needed @code{n}
1872 @opindex compliant-needed
1873 Number of completely trusted users to introduce a new
1874 key signer (defaults to 1).
1876 @item --marginals-needed @code{n}
1877 @opindex marginals-needed
1878 Number of marginally trusted users to introduce a new
1879 key signer (defaults to 3)
1881 @item --tofu-default-policy @code{auto|good|unknown|bad|ask}
1882 @opindex tofu-default-policy
1883 The default TOFU policy (defaults to @code{auto}). For more
1884 information about the meaning of this option, @pxref{trust-model-tofu}.
1886 @item --max-cert-depth @code{n}
1887 @opindex max-cert-depth
1888 Maximum depth of a certification chain (default is 5).
1890 @item --no-sig-cache
1891 @opindex no-sig-cache
1892 Do not cache the verification status of key signatures.
1893 Caching gives a much better performance in key listings. However, if
1894 you suspect that your public keyring is not safe against write
1895 modifications, you can use this option to disable the caching. It
1896 probably does not make sense to disable it because all kind of damage
1897 can be done if someone else has write access to your public keyring.
1899 @item --auto-check-trustdb
1900 @itemx --no-auto-check-trustdb
1901 @opindex auto-check-trustdb
1902 If GnuPG feels that its information about the Web of Trust has to be
1903 updated, it automatically runs the @option{--check-trustdb} command
1904 internally. This may be a time consuming
1905 process. @option{--no-auto-check-trustdb} disables this option.
1908 @itemx --no-use-agent
1910 This is dummy option. @command{@gpgname} always requires the agent.
1912 @item --gpg-agent-info
1913 @opindex gpg-agent-info
1914 This is dummy option. It has no effect when used with @command{@gpgname}.
1917 @item --agent-program @var{file}
1918 @opindex agent-program
1919 Specify an agent program to be used for secret key operations. The
1920 default value is determined by running @command{gpgconf} with the
1921 option @option{--list-dirs}. Note that the pipe symbol (@code{|}) is
1922 used for a regression test suite hack and may thus not be used in the
1925 @item --dirmngr-program @var{file}
1926 @opindex dirmngr-program
1927 Specify a dirmngr program to be used for keyserver access. The
1928 default value is @file{@value{BINDIR}/dirmngr}.
1930 @item --no-autostart
1931 @opindex no-autostart
1932 Do not start the gpg-agent or the dirmngr if it has not yet been
1933 started and its service is required. This option is mostly useful on
1934 machines where the connection to gpg-agent has been redirected to
1935 another machines. If dirmngr is required on the remote machine, it
1936 may be started manually using @command{gpgconf --launch dirmngr}.
1940 Lock the databases the first time a lock is requested
1941 and do not release the lock until the process
1944 @item --lock-multiple
1945 @opindex lock-multiple
1946 Release the locks every time a lock is no longer
1947 needed. Use this to override a previous @option{--lock-once}
1952 Disable locking entirely. This option should be used only in very
1953 special environments, where it can be assured that only one process
1954 is accessing those files. A bootable floppy with a stand-alone
1955 encryption system will probably use this. Improper usage of this
1956 option may lead to data and key corruption.
1958 @item --exit-on-status-write-error
1959 @opindex exit-on-status-write-error
1960 This option will cause write errors on the status FD to immediately
1961 terminate the process. That should in fact be the default but it never
1962 worked this way and thus we need an option to enable this, so that the
1963 change won't break applications which close their end of a status fd
1964 connected pipe too early. Using this option along with
1965 @option{--enable-progress-filter} may be used to cleanly cancel long
1966 running gpg operations.
1968 @item --limit-card-insert-tries @code{n}
1969 @opindex limit-card-insert-tries
1970 With @code{n} greater than 0 the number of prompts asking to insert a
1971 smartcard gets limited to N-1. Thus with a value of 1 gpg won't at
1972 all ask to insert a card if none has been inserted at startup. This
1973 option is useful in the configuration file in case an application does
1974 not know about the smartcard support and waits ad infinitum for an
1977 @item --no-random-seed-file
1978 @opindex no-random-seed-file
1979 GnuPG uses a file to store its internal random pool over invocations.
1980 This makes random generation faster; however sometimes write operations
1981 are not desired. This option can be used to achieve that with the cost of
1982 slower random generation.
1985 @opindex no-greeting
1986 Suppress the initial copyright message.
1988 @item --no-secmem-warning
1989 @opindex no-secmem-warning
1990 Suppress the warning about "using insecure memory".
1992 @item --no-permission-warning
1993 @opindex permission-warning
1994 Suppress the warning about unsafe file and home directory (@option{--homedir})
1995 permissions. Note that the permission checks that GnuPG performs are
1996 not intended to be authoritative, but rather they simply warn about
1997 certain common permission problems. Do not assume that the lack of a
1998 warning means that your system is secure.
2000 Note that the warning for unsafe @option{--homedir} permissions cannot be
2001 suppressed in the gpg.conf file, as this would allow an attacker to
2002 place an unsafe gpg.conf file in place, and use this file to suppress
2003 warnings about itself. The @option{--homedir} permissions warning may only be
2004 suppressed on the command line.
2006 @item --no-mdc-warning
2007 @opindex no-mdc-warning
2008 Suppress the warning about missing MDC integrity protection.
2010 @item --require-secmem
2011 @itemx --no-require-secmem
2012 @opindex require-secmem
2013 Refuse to run if GnuPG cannot get secure memory. Defaults to no
2014 (i.e. run, but give a warning).
2017 @item --require-cross-certification
2018 @itemx --no-require-cross-certification
2019 @opindex require-cross-certification
2020 When verifying a signature made from a subkey, ensure that the cross
2021 certification "back signature" on the subkey is present and valid. This
2022 protects against a subtle attack against subkeys that can sign.
2023 Defaults to @option{--require-cross-certification} for
2029 Allow the user to do certain nonsensical or "silly" things like
2030 signing an expired or revoked key, or certain potentially incompatible
2031 things like generating unusual key types. This also disables certain
2032 warning messages about potentially incompatible actions. As the name
2033 implies, this option is for experts only. If you don't fully
2034 understand the implications of what it allows you to do, leave this
2035 off. @option{--no-expert} disables this option.
2040 @c *******************************************
2041 @c ******** KEY RELATED OPTIONS ************
2042 @c *******************************************
2043 @node GPG Key related Options
2044 @subsection Key related options
2048 @item --recipient @var{name}
2051 Encrypt for user id @var{name}. If this option or
2052 @option{--hidden-recipient} is not specified, GnuPG asks for the user-id
2053 unless @option{--default-recipient} is given.
2055 @item --hidden-recipient @var{name}
2057 @opindex hidden-recipient
2058 Encrypt for user ID @var{name}, but hide the key ID of this user's
2059 key. This option helps to hide the receiver of the message and is a
2060 limited countermeasure against traffic analysis. If this option or
2061 @option{--recipient} is not specified, GnuPG asks for the user ID unless
2062 @option{--default-recipient} is given.
2064 @item --recipient-file @var{file}
2066 @opindex recipient-file
2067 This option is similar to @option{--recipient} except that it
2068 encrypts to a key stored in the given file. @var{file} must be the
2069 name of a file containing exactly one key. @command{@gpgname} assumes that
2070 the key in this file is fully valid.
2072 @item --hidden-recipient-file @var{file}
2074 @opindex hidden-recipient-file
2075 This option is similar to @option{--hidden-recipient} except that it
2076 encrypts to a key stored in the given file. @var{file} must be the
2077 name of a file containing exactly one key. @command{@gpgname} assumes that
2078 the key in this file is fully valid.
2080 @item --encrypt-to @code{name}
2082 Same as @option{--recipient} but this one is intended for use in the
2083 options file and may be used with your own user-id as an
2084 "encrypt-to-self". These keys are only used when there are other
2085 recipients given either by use of @option{--recipient} or by the asked
2086 user id. No trust checking is performed for these user ids and even
2087 disabled keys can be used.
2089 @item --hidden-encrypt-to @code{name}
2090 @opindex hidden-encrypt-to
2091 Same as @option{--hidden-recipient} but this one is intended for use in the
2092 options file and may be used with your own user-id as a hidden
2093 "encrypt-to-self". These keys are only used when there are other
2094 recipients given either by use of @option{--recipient} or by the asked user id.
2095 No trust checking is performed for these user ids and even disabled
2098 @item --no-encrypt-to
2099 @opindex no-encrypt-to
2100 Disable the use of all @option{--encrypt-to} and
2101 @option{--hidden-encrypt-to} keys.
2103 @item --group @code{name=value}
2105 Sets up a named group, which is similar to aliases in email programs.
2106 Any time the group name is a recipient (@option{-r} or
2107 @option{--recipient}), it will be expanded to the values
2108 specified. Multiple groups with the same name are automatically merged
2109 into a single group.
2111 The values are @code{key IDs} or fingerprints, but any key description
2112 is accepted. Note that a value with spaces in it will be treated as
2113 two different values. Note also there is only one level of expansion
2114 --- you cannot make an group that points to another group. When used
2115 from the command line, it may be necessary to quote the argument to
2116 this option to prevent the shell from treating it as multiple
2119 @item --ungroup @code{name}
2121 Remove a given entry from the @option{--group} list.
2125 Remove all entries from the @option{--group} list.
2127 @item --local-user @var{name}
2130 Use @var{name} as the key to sign with. Note that this option overrides
2131 @option{--default-key}.
2133 @item --sender @var{mbox}
2135 This option has two purposes. @var{mbox} must either be a complete
2136 user id with a proper mail address or just a mail address. When
2137 creating a signature this option tells gpg the user id of a key used
2138 to make a signature if the key was not directly specified by a user
2139 id. When verifying a signature the @var{mbox} is used to restrict the
2140 information printed by the TOFU code to matching user ids.
2142 @item --try-secret-key @var{name}
2143 @opindex try-secret-key
2144 For hidden recipients GPG needs to know the keys to use for trial
2145 decryption. The key set with @option{--default-key} is always tried
2146 first, but this is often not sufficient. This option allows setting more
2147 keys to be used for trial decryption. Although any valid user-id
2148 specification may be used for @var{name} it makes sense to use at least
2149 the long keyid to avoid ambiguities. Note that gpg-agent might pop up a
2150 pinentry for a lot keys to do the trial decryption. If you want to stop
2151 all further trial decryption you may use close-window button instead of
2154 @item --try-all-secrets
2155 @opindex try-all-secrets
2156 Don't look at the key ID as stored in the message but try all secret
2157 keys in turn to find the right decryption key. This option forces the
2158 behaviour as used by anonymous recipients (created by using
2159 @option{--throw-keyids} or @option{--hidden-recipient}) and might come
2160 handy in case where an encrypted message contains a bogus key ID.
2162 @item --skip-hidden-recipients
2163 @itemx --no-skip-hidden-recipients
2164 @opindex skip-hidden-recipients
2165 @opindex no-skip-hidden-recipients
2166 During decryption skip all anonymous recipients. This option helps in
2167 the case that people use the hidden recipients feature to hide there
2168 own encrypt-to key from others. If oneself has many secret keys this
2169 may lead to a major annoyance because all keys are tried in turn to
2170 decrypt something which was not really intended for it. The drawback
2171 of this option is that it is currently not possible to decrypt a
2172 message which includes real anonymous recipients.
2177 @c *******************************************
2178 @c ******** INPUT AND OUTPUT ***************
2179 @c *******************************************
2180 @node GPG Input and Output
2181 @subsection Input and Output
2188 Create ASCII armored output. The default is to create the binary
2193 Assume the input data is not in ASCII armored format.
2195 @item --output @var{file}
2196 @itemx -o @var{file}
2198 Write output to @var{file}. To write to stdout use @code{-} as the
2201 @item --max-output @code{n}
2203 This option sets a limit on the number of bytes that will be generated
2204 when processing a file. Since OpenPGP supports various levels of
2205 compression, it is possible that the plaintext of a given message may be
2206 significantly larger than the original OpenPGP message. While GnuPG
2207 works properly with such messages, there is often a desire to set a
2208 maximum file size that will be generated before processing is forced to
2209 stop by the OS limits. Defaults to 0, which means "no limit".
2211 @item --input-size-hint @var{n}
2212 @opindex input-size-hint
2213 This option can be used to tell GPG the size of the input data in
2214 bytes. @var{n} must be a positive base-10 number. This option is
2215 only useful if the input is not taken from a file. GPG may use this
2216 hint to optimize its buffer allocation strategy. It is also used by
2217 the @option{--status-fd} line ``PROGRESS'' to provide a value for
2218 ``total'' if that is not available by other means.
2220 @item --import-options @code{parameters}
2221 @opindex import-options
2222 This is a space or comma delimited string that gives options for
2223 importing keys. Options can be prepended with a `no-' to give the
2224 opposite meaning. The options are:
2228 @item import-local-sigs
2229 Allow importing key signatures marked as "local". This is not
2230 generally useful unless a shared keyring scheme is being used.
2233 @item keep-ownertrust
2234 Normally possible still existing ownertrust values of a key are
2235 cleared if a key is imported. This is in general desirable so that
2236 a formerly deleted key does not automatically gain an ownertrust
2237 values merely due to import. On the other hand it is sometimes
2238 necessary to re-import a trusted set of keys again but keeping
2239 already assigned ownertrust values. This can be achieved by using
2242 @item repair-pks-subkey-bug
2243 During import, attempt to repair the damage caused by the PKS keyserver
2244 bug (pre version 0.9.6) that mangles keys with multiple subkeys. Note
2245 that this cannot completely repair the damaged key as some crucial data
2246 is removed by the keyserver, but it does at least give you back one
2247 subkey. Defaults to no for regular @option{--import} and to yes for
2248 keyserver @option{--receive-keys}.
2251 Show a listing of the key as imported right before it is stored.
2252 This can be combined with the option @option{--dry-run} to only look
2256 Run the entire import code but instead of storing the key to the
2257 local keyring write it to the output. The export options
2258 @option{export-pka} and @option{export-dane} affect the output. This
2259 option can be used to remove all invalid parts from a key without the
2263 During import, allow key updates to existing keys, but do not allow
2264 any new keys to be imported. Defaults to no.
2267 After import, compact (remove all signatures except the
2268 self-signature) any user IDs from the new key that are not usable.
2269 Then, remove any signatures from the new key that are not usable.
2270 This includes signatures that were issued by keys that are not present
2271 on the keyring. This option is the same as running the @option{--edit-key}
2272 command "clean" after import. Defaults to no.
2274 @item import-minimal
2275 Import the smallest key possible. This removes all signatures except
2276 the most recent self-signature on each user ID. This option is the
2277 same as running the @option{--edit-key} command "minimize" after import.
2281 @item --import-filter @code{@var{name}=@var{expr}}
2282 @itemx --export-filter @code{@var{name}=@var{expr}}
2283 @opindex import-filter
2284 @opindex export-filter
2285 These options define an import/export filter which are applied to the
2286 imported/exported keyblock right before it will be stored/written.
2287 @var{name} defines the type of filter to use, @var{expr} the
2288 expression to evaluate. The option can be used several times which
2289 then appends more expression to the same @var{name}.
2292 The available filter types are:
2297 This filter will keep a user id packet and its dependent packets in
2298 the keyblock if the expression evaluates to true.
2301 This filter drops the selected subkeys.
2302 Currently only implemented for --export-filter.
2305 This filter drops the selected key signatures on user ids.
2306 Self-signatures are not considered.
2307 Currently only implemented for --import-filter.
2311 For the syntax of the expression see the chapter "FILTER EXPRESSIONS".
2312 The property names for the expressions depend on the actual filter
2313 type and are indicated in the following table.
2315 The available properties are:
2320 A string with the user id. (keep-uid)
2323 The addr-spec part of a user id with mailbox or the empty string.
2327 A number with the public key algorithm of a key or subkey packet.
2331 @itemx key_created_d
2332 The first is the timestamp a public key or subkey packet was
2333 created. The second is the same but given as an ISO string,
2334 e.g. "2016-08-17". (drop-subkey)
2337 Boolean indicating whether the user id is the primary one. (keep-uid)
2340 Boolean indicating whether a key or subkey is a secret one.
2344 @itemx sig_created_d
2345 The first is the timestamp a signature packet was created. The
2346 second is the same but given as an ISO string,
2347 e.g. "2016-08-17". (drop-sig)
2350 A number with the public key algorithm of a signature packet. (drop-sig)
2352 @item sig_digest_algo
2353 A number with the digest algorithm of a signature packet. (drop-sig)
2357 @item --export-options @code{parameters}
2358 @opindex export-options
2359 This is a space or comma delimited string that gives options for
2360 exporting keys. Options can be prepended with a `no-' to give the
2361 opposite meaning. The options are:
2365 @item export-local-sigs
2366 Allow exporting key signatures marked as "local". This is not
2367 generally useful unless a shared keyring scheme is being used.
2370 @item export-attributes
2371 Include attribute user IDs (photo IDs) while exporting. This is
2372 useful to export keys if they are going to be used by an OpenPGP
2373 program that does not accept attribute user IDs. Defaults to yes.
2375 @item export-sensitive-revkeys
2376 Include designated revoker information that was marked as
2377 "sensitive". Defaults to no.
2379 @c Since GnuPG 2.1 gpg-agent manages the secret key and thus the
2380 @c export-reset-subkey-passwd hack is not anymore justified. Such use
2381 @c cases may be implemented using a specialized secret key export
2383 @c @item export-reset-subkey-passwd
2384 @c When using the @option{--export-secret-subkeys} command, this option resets
2385 @c the passphrases for all exported subkeys to empty. This is useful
2386 @c when the exported subkey is to be used on an unattended machine where
2387 @c a passphrase doesn't necessarily make sense. Defaults to no.
2390 Compact (remove all signatures from) user IDs on the key being
2391 exported if the user IDs are not usable. Also, do not export any
2392 signatures that are not usable. This includes signatures that were
2393 issued by keys that are not present on the keyring. This option is
2394 the same as running the @option{--edit-key} command "clean" before export
2395 except that the local copy of the key is not modified. Defaults to
2398 @item export-minimal
2399 Export the smallest key possible. This removes all signatures except the
2400 most recent self-signature on each user ID. This option is the same as
2401 running the @option{--edit-key} command "minimize" before export except
2402 that the local copy of the key is not modified. Defaults to no.
2405 Instead of outputting the key material output PKA records suitable
2406 to put into DNS zone files. An ORIGIN line is printed before each
2407 record to allow diverting the records to the corresponding zone file.
2410 Instead of outputting the key material output OpenPGP DANE records
2411 suitable to put into DNS zone files. An ORIGIN line is printed before
2412 each record to allow diverting the records to the corresponding zone
2418 @opindex with-colons
2419 Print key listings delimited by colons. Note that the output will be
2420 encoded in UTF-8 regardless of any @option{--display-charset} setting. This
2421 format is useful when GnuPG is called from scripts and other programs
2422 as it is easily machine parsed. The details of this format are
2423 documented in the file @file{doc/DETAILS}, which is included in the GnuPG
2424 source distribution.
2426 @item --fixed-list-mode
2427 @opindex fixed-list-mode
2428 Do not merge primary user ID and primary key in @option{--with-colon}
2429 listing mode and print all timestamps as seconds since 1970-01-01.
2430 Since GnuPG 2.0.10, this mode is always used and thus this option is
2431 obsolete; it does not harm to use it though.
2433 @item --legacy-list-mode
2434 @opindex legacy-list-mode
2435 Revert to the pre-2.1 public key list mode. This only affects the
2436 human readable output and not the machine interface
2437 (i.e. @code{--with-colons}). Note that the legacy format does not
2438 convey suitable information for elliptic curves.
2440 @item --with-fingerprint
2441 @opindex with-fingerprint
2442 Same as the command @option{--fingerprint} but changes only the format
2443 of the output and may be used together with another command.
2445 @item --with-subkey-fingerprint
2446 @opindex with-subkey-fingerprint
2447 If a fingerprint is printed for the primary key, this option forces
2448 printing of the fingerprint for all subkeys. This could also be
2449 achieved by using the @option{--with-fingerprint} twice but by using
2450 this option along with keyid-format "none" a compact fingerprint is
2453 @item --with-icao-spelling
2454 @opindex with-icao-spelling
2455 Print the ICAO spelling of the fingerprint in addition to the hex digits.
2457 @item --with-keygrip
2458 @opindex with-keygrip
2459 Include the keygrip in the key listings. In @code{--with-colons} mode
2460 this is implicitly enable for secret keys.
2462 @item --with-wkd-hash
2463 @opindex with-wkd-hash
2464 Print a Web Key Directory identifier along with each user ID in key
2465 listings. This is an experimental feature and semantics may change.
2468 @opindex with-secret
2469 Include info about the presence of a secret key in public key listings
2470 done with @code{--with-colons}.
2474 @c *******************************************
2475 @c ******** OPENPGP OPTIONS ****************
2476 @c *******************************************
2477 @node OpenPGP Options
2478 @subsection OpenPGP protocol specific options
2482 @item -t, --textmode
2483 @itemx --no-textmode
2485 Treat input files as text and store them in the OpenPGP canonical text
2486 form with standard "CRLF" line endings. This also sets the necessary
2487 flags to inform the recipient that the encrypted or signed data is text
2488 and may need its line endings converted back to whatever the local
2489 system uses. This option is useful when communicating between two
2490 platforms that have different line ending conventions (UNIX-like to Mac,
2491 Mac to Windows, etc). @option{--no-textmode} disables this option, and
2494 @item --force-v3-sigs
2495 @itemx --no-force-v3-sigs
2496 @item --force-v4-certs
2497 @itemx --no-force-v4-certs
2498 These options are obsolete and have no effect since GnuPG 2.1.
2502 Force the use of encryption with a modification detection code. This
2503 is always used with the newer ciphers (those with a blocksize greater
2504 than 64 bits), or if all of the recipient keys indicate MDC support in
2505 their feature flags.
2508 @opindex disable-mdc
2509 Disable the use of the modification detection code. Note that by
2510 using this option, the encrypted message becomes vulnerable to a
2511 message modification attack.
2513 @item --disable-signer-uid
2514 @opindex disable-signer-uid
2515 By default the user ID of the signing key is embedded in the data
2516 signature. As of now this is only done if the signing key has been
2517 specified with @option{local-user} using a mail address. This
2518 information can be helpful for verifier to locate the key; see
2519 option @option{--auto-key-retrieve}.
2521 @item --personal-cipher-preferences @code{string}
2522 @opindex personal-cipher-preferences
2523 Set the list of personal cipher preferences to @code{string}. Use
2524 @command{@gpgname --version} to get a list of available algorithms,
2525 and use @code{none} to set no preference at all. This allows the user
2526 to safely override the algorithm chosen by the recipient key
2527 preferences, as GPG will only select an algorithm that is usable by
2528 all recipients. The most highly ranked cipher in this list is also
2529 used for the @option{--symmetric} encryption command.
2531 @item --personal-digest-preferences @code{string}
2532 @opindex personal-digest-preferences
2533 Set the list of personal digest preferences to @code{string}. Use
2534 @command{@gpgname --version} to get a list of available algorithms,
2535 and use @code{none} to set no preference at all. This allows the user
2536 to safely override the algorithm chosen by the recipient key
2537 preferences, as GPG will only select an algorithm that is usable by
2538 all recipients. The most highly ranked digest algorithm in this list
2539 is also used when signing without encryption
2540 (e.g. @option{--clear-sign} or @option{--sign}).
2542 @item --personal-compress-preferences @code{string}
2543 @opindex personal-compress-preferences
2544 Set the list of personal compression preferences to @code{string}.
2545 Use @command{@gpgname --version} to get a list of available
2546 algorithms, and use @code{none} to set no preference at all. This
2547 allows the user to safely override the algorithm chosen by the
2548 recipient key preferences, as GPG will only select an algorithm that
2549 is usable by all recipients. The most highly ranked compression
2550 algorithm in this list is also used when there are no recipient keys
2551 to consider (e.g. @option{--symmetric}).
2553 @item --s2k-cipher-algo @code{name}
2554 @opindex s2k-cipher-algo
2555 Use @code{name} as the cipher algorithm for symmetric encryption with
2556 a passphrase if @option{--personal-cipher-preferences} and
2557 @option{--cipher-algo} are not given. The default is @value{GPGSYMENCALGO}.
2559 @item --s2k-digest-algo @code{name}
2560 @opindex s2k-digest-algo
2561 Use @code{name} as the digest algorithm used to mangle the passphrases
2562 for symmetric encryption. The default is SHA-1.
2564 @item --s2k-mode @code{n}
2566 Selects how passphrases for symmetric encryption are mangled. If
2567 @code{n} is 0 a plain passphrase (which is in general not recommended)
2568 will be used, a 1 adds a salt (which should not be used) to the
2569 passphrase and a 3 (the default) iterates the whole process a number
2570 of times (see @option{--s2k-count}).
2572 @item --s2k-count @code{n}
2574 Specify how many times the passphrases mangling for symmetric
2575 encryption is repeated. This value may range between 1024 and
2576 65011712 inclusive. The default is inquired from gpg-agent. Note
2577 that not all values in the 1024-65011712 range are legal and if an
2578 illegal value is selected, GnuPG will round up to the nearest legal
2579 value. This option is only meaningful if @option{--s2k-mode} is set
2580 to the default of 3.
2585 @c ***************************
2586 @c ******* Compliance ********
2587 @c ***************************
2588 @node Compliance Options
2589 @subsection Compliance options
2591 These options control what GnuPG is compliant to. Only one of these
2592 options may be active at a time. Note that the default setting of
2593 this is nearly always the correct one. See the INTEROPERABILITY WITH
2594 OTHER OPENPGP PROGRAMS section below before using one of these
2601 Use standard GnuPG behavior. This is essentially OpenPGP behavior
2602 (see @option{--openpgp}), but with some additional workarounds for common
2603 compatibility problems in different versions of PGP. This is the
2604 default option, so it is not generally needed, but it may be useful to
2605 override a different compliance option in the gpg.conf file.
2609 Reset all packet, cipher and digest options to strict OpenPGP
2610 behavior. Use this option to reset all previous options like
2611 @option{--s2k-*}, @option{--cipher-algo}, @option{--digest-algo} and
2612 @option{--compress-algo} to OpenPGP compliant values. All PGP
2613 workarounds are disabled.
2617 Reset all packet, cipher and digest options to strict RFC-4880
2618 behavior. Note that this is currently the same thing as
2623 Enable experimental features from proposed updates to RFC-4880. This
2624 option can be used in addition to the other compliance options.
2625 Warning: The behavior may change with any GnuPG release and created
2626 keys or data may not be usable with future GnuPG versions.
2630 Reset all packet, cipher and digest options to strict RFC-2440
2635 Set up all options to be as PGP 6 compliant as possible. This
2636 restricts you to the ciphers IDEA (if the IDEA plugin is installed),
2637 3DES, and CAST5, the hashes MD5, SHA1 and RIPEMD160, and the
2638 compression algorithms none and ZIP. This also disables
2639 @option{--throw-keyids}, and making signatures with signing subkeys as PGP 6
2640 does not understand signatures made by signing subkeys.
2642 This option implies @option{--disable-mdc --escape-from-lines}.
2646 Set up all options to be as PGP 7 compliant as possible. This is
2647 identical to @option{--pgp6} except that MDCs are not disabled, and the
2648 list of allowable ciphers is expanded to add AES128, AES192, AES256, and
2653 Set up all options to be as PGP 8 compliant as possible. PGP 8 is a lot
2654 closer to the OpenPGP standard than previous versions of PGP, so all
2655 this does is disable @option{--throw-keyids} and set
2656 @option{--escape-from-lines}. All algorithms are allowed except for the
2657 SHA224, SHA384, and SHA512 digests.
2659 @item --compliance @var{string}
2661 This option can be used instead of one of the options above. Valid
2662 values for @var{string} are the above option names (without the double
2663 dash) and possibly others as shown when using "help" for @var{value}.
2668 @c *******************************************
2669 @c ******** ESOTERIC OPTIONS ***************
2670 @c *******************************************
2671 @node GPG Esoteric Options
2672 @subsection Doing things one usually doesn't want to do
2679 Don't make any changes (this is not completely implemented).
2683 Changes the behaviour of some commands. This is like @option{--dry-run} but
2684 different in some cases. The semantic of this option may be extended in
2685 the future. Currently it only skips the actual decryption pass and
2686 therefore enables a fast listing of the encryption keys.
2689 @itemx --interactive
2690 @opindex interactive
2691 Prompt before overwriting any files.
2693 @item --debug-level @var{level}
2694 @opindex debug-level
2695 Select the debug level for investigating problems. @var{level} may be
2696 a numeric value or by a keyword:
2700 No debugging at all. A value of less than 1 may be used instead of
2703 Some basic debug messages. A value between 1 and 2 may be used
2704 instead of the keyword.
2706 More verbose debug messages. A value between 3 and 5 may be used
2707 instead of the keyword.
2709 Even more detailed messages. A value between 6 and 8 may be used
2710 instead of the keyword.
2712 All of the debug messages you can get. A value greater than 8 may be
2713 used instead of the keyword. The creation of hash tracing files is
2714 only enabled if the keyword is used.
2717 How these messages are mapped to the actual debugging flags is not
2718 specified and may change with newer releases of this program. They are
2719 however carefully selected to best aid in debugging.
2721 @item --debug @var{flags}
2723 Set debugging flags. All flags are or-ed and @var{flags} may be given
2724 in C syntax (e.g. 0x0042) or as a comma separated list of flag names.
2725 To get a list of all supported flags the single word "help" can be
2730 Set all useful debugging flags.
2733 @opindex debug-iolbf
2734 Set stdout into line buffered mode. This option is only honored when
2735 given on the command line.
2737 @item --faked-system-time @var{epoch}
2738 @opindex faked-system-time
2739 This option is only useful for testing; it sets the system time back or
2740 forth to @var{epoch} which is the number of seconds elapsed since the year
2741 1970. Alternatively @var{epoch} may be given as a full ISO time string
2742 (e.g. "20070924T154812").
2744 @item --enable-progress-filter
2745 @opindex enable-progress-filter
2746 Enable certain PROGRESS status outputs. This option allows frontends
2747 to display a progress indicator while gpg is processing larger files.
2748 There is a slight performance overhead using it.
2750 @item --status-fd @code{n}
2752 Write special status strings to the file descriptor @code{n}.
2753 See the file DETAILS in the documentation for a listing of them.
2755 @item --status-file @code{file}
2756 @opindex status-file
2757 Same as @option{--status-fd}, except the status data is written to file
2760 @item --logger-fd @code{n}
2762 Write log output to file descriptor @code{n} and not to STDERR.
2764 @item --log-file @code{file}
2765 @itemx --logger-file @code{file}
2767 Same as @option{--logger-fd}, except the logger data is written to
2768 file @code{file}. Use @file{socket://} to log to socket.
2770 @item --attribute-fd @code{n}
2771 @opindex attribute-fd
2772 Write attribute subpackets to the file descriptor @code{n}. This is most
2773 useful for use with @option{--status-fd}, since the status messages are
2774 needed to separate out the various subpackets from the stream delivered
2775 to the file descriptor.
2777 @item --attribute-file @code{file}
2778 @opindex attribute-file
2779 Same as @option{--attribute-fd}, except the attribute data is written to
2782 @item --comment @code{string}
2783 @itemx --no-comments
2785 Use @code{string} as a comment string in cleartext signatures and ASCII
2786 armored messages or keys (see @option{--armor}). The default behavior is
2787 not to use a comment string. @option{--comment} may be repeated multiple
2788 times to get multiple comment strings. @option{--no-comments} removes
2789 all comments. It is a good idea to keep the length of a single comment
2790 below 60 characters to avoid problems with mail programs wrapping such
2791 lines. Note that comment lines, like all other header lines, are not
2792 protected by the signature.
2794 @item --emit-version
2795 @itemx --no-emit-version
2796 @opindex emit-version
2797 Force inclusion of the version string in ASCII armored output. If
2798 given once only the name of the program and the major number is
2799 emitted, given twice the minor is also emitted, given thrice
2800 the micro is added, and given four times an operating system identification
2801 is also emitted. @option{--no-emit-version} (default) disables the version
2804 @item --sig-notation @code{name=value}
2805 @itemx --cert-notation @code{name=value}
2806 @itemx -N, --set-notation @code{name=value}
2807 @opindex sig-notation
2808 @opindex cert-notation
2809 @opindex set-notation
2810 Put the name value pair into the signature as notation data.
2811 @code{name} must consist only of printable characters or spaces, and
2812 must contain a '@@' character in the form keyname@@domain.example.com
2813 (substituting the appropriate keyname and domain name, of course). This
2814 is to help prevent pollution of the IETF reserved notation
2815 namespace. The @option{--expert} flag overrides the '@@'
2816 check. @code{value} may be any printable string; it will be encoded in
2817 UTF-8, so you should check that your @option{--display-charset} is set
2818 correctly. If you prefix @code{name} with an exclamation mark (!), the
2819 notation data will be flagged as critical
2820 (rfc4880:5.2.3.16). @option{--sig-notation} sets a notation for data
2821 signatures. @option{--cert-notation} sets a notation for key signatures
2822 (certifications). @option{--set-notation} sets both.
2824 There are special codes that may be used in notation names. "%k" will
2825 be expanded into the key ID of the key being signed, "%K" into the
2826 long key ID of the key being signed, "%f" into the fingerprint of the
2827 key being signed, "%s" into the key ID of the key making the
2828 signature, "%S" into the long key ID of the key making the signature,
2829 "%g" into the fingerprint of the key making the signature (which might
2830 be a subkey), "%p" into the fingerprint of the primary key of the key
2831 making the signature, "%c" into the signature count from the OpenPGP
2832 smartcard, and "%%" results in a single "%". %k, %K, and %f are only
2833 meaningful when making a key signature (certification), and %c is only
2834 meaningful when using the OpenPGP smartcard.
2836 @item --sig-policy-url @code{string}
2837 @itemx --cert-policy-url @code{string}
2838 @itemx --set-policy-url @code{string}
2839 @opindex sig-policy-url
2840 @opindex cert-policy-url
2841 @opindex set-policy-url
2842 Use @code{string} as a Policy URL for signatures (rfc4880:5.2.3.20). If
2843 you prefix it with an exclamation mark (!), the policy URL packet will
2844 be flagged as critical. @option{--sig-policy-url} sets a policy url for
2845 data signatures. @option{--cert-policy-url} sets a policy url for key
2846 signatures (certifications). @option{--set-policy-url} sets both.
2848 The same %-expandos used for notation data are available here as well.
2850 @item --sig-keyserver-url @code{string}
2851 @opindex sig-keyserver-url
2852 Use @code{string} as a preferred keyserver URL for data signatures. If
2853 you prefix it with an exclamation mark (!), the keyserver URL packet
2854 will be flagged as critical.
2856 The same %-expandos used for notation data are available here as well.
2858 @item --set-filename @code{string}
2859 @opindex set-filename
2860 Use @code{string} as the filename which is stored inside messages.
2861 This overrides the default, which is to use the actual filename of the
2862 file being encrypted. Using the empty string for @code{string}
2863 effectively removes the filename from the output.
2865 @item --for-your-eyes-only
2866 @itemx --no-for-your-eyes-only
2867 @opindex for-your-eyes-only
2868 Set the `for your eyes only' flag in the message. This causes GnuPG to
2869 refuse to save the file unless the @option{--output} option is given,
2870 and PGP to use a "secure viewer" with a claimed Tempest-resistant font
2871 to display the message. This option overrides @option{--set-filename}.
2872 @option{--no-for-your-eyes-only} disables this option.
2874 @item --use-embedded-filename
2875 @itemx --no-use-embedded-filename
2876 @opindex use-embedded-filename
2877 Try to create a file with a name as embedded in the data. This can be
2878 a dangerous option as it enables overwriting files. Defaults to no.
2880 @item --cipher-algo @code{name}
2881 @opindex cipher-algo
2882 Use @code{name} as cipher algorithm. Running the program with the
2883 command @option{--version} yields a list of supported algorithms. If
2884 this is not used the cipher algorithm is selected from the preferences
2885 stored with the key. In general, you do not want to use this option as
2886 it allows you to violate the OpenPGP standard.
2887 @option{--personal-cipher-preferences} is the safe way to accomplish the
2890 @item --digest-algo @code{name}
2891 @opindex digest-algo
2892 Use @code{name} as the message digest algorithm. Running the program
2893 with the command @option{--version} yields a list of supported algorithms. In
2894 general, you do not want to use this option as it allows you to
2895 violate the OpenPGP standard. @option{--personal-digest-preferences} is the
2896 safe way to accomplish the same thing.
2898 @item --compress-algo @code{name}
2899 @opindex compress-algo
2900 Use compression algorithm @code{name}. "zlib" is RFC-1950 ZLIB
2901 compression. "zip" is RFC-1951 ZIP compression which is used by PGP.
2902 "bzip2" is a more modern compression scheme that can compress some
2903 things better than zip or zlib, but at the cost of more memory used
2904 during compression and decompression. "uncompressed" or "none"
2905 disables compression. If this option is not used, the default
2906 behavior is to examine the recipient key preferences to see which
2907 algorithms the recipient supports. If all else fails, ZIP is used for
2908 maximum compatibility.
2910 ZLIB may give better compression results than ZIP, as the compression
2911 window size is not limited to 8k. BZIP2 may give even better
2912 compression results than that, but will use a significantly larger
2913 amount of memory while compressing and decompressing. This may be
2914 significant in low memory situations. Note, however, that PGP (all
2915 versions) only supports ZIP compression. Using any algorithm other
2916 than ZIP or "none" will make the message unreadable with PGP. In
2917 general, you do not want to use this option as it allows you to
2918 violate the OpenPGP standard. @option{--personal-compress-preferences} is the
2919 safe way to accomplish the same thing.
2921 @item --cert-digest-algo @code{name}
2922 @opindex cert-digest-algo
2923 Use @code{name} as the message digest algorithm used when signing a
2924 key. Running the program with the command @option{--version} yields a
2925 list of supported algorithms. Be aware that if you choose an algorithm
2926 that GnuPG supports but other OpenPGP implementations do not, then some
2927 users will not be able to use the key signatures you make, or quite
2928 possibly your entire key.
2930 @item --disable-cipher-algo @code{name}
2931 @opindex disable-cipher-algo
2932 Never allow the use of @code{name} as cipher algorithm.
2933 The given name will not be checked so that a later loaded algorithm
2934 will still get disabled.
2936 @item --disable-pubkey-algo @code{name}
2937 @opindex disable-pubkey-algo
2938 Never allow the use of @code{name} as public key algorithm.
2939 The given name will not be checked so that a later loaded algorithm
2940 will still get disabled.
2942 @item --throw-keyids
2943 @itemx --no-throw-keyids
2944 @opindex throw-keyids
2945 Do not put the recipient key IDs into encrypted messages. This helps to
2946 hide the receivers of the message and is a limited countermeasure
2947 against traffic analysis.@footnote{Using a little social engineering
2948 anyone who is able to decrypt the message can check whether one of the
2949 other recipients is the one he suspects.} On the receiving side, it may
2950 slow down the decryption process because all available secret keys must
2951 be tried. @option{--no-throw-keyids} disables this option. This option
2952 is essentially the same as using @option{--hidden-recipient} for all
2955 @item --not-dash-escaped
2956 @opindex not-dash-escaped
2957 This option changes the behavior of cleartext signatures
2958 so that they can be used for patch files. You should not
2959 send such an armored file via email because all spaces
2960 and line endings are hashed too. You can not use this
2961 option for data which has 5 dashes at the beginning of a
2962 line, patch files don't have this. A special armor header
2963 line tells GnuPG about this cleartext signature option.
2965 @item --escape-from-lines
2966 @itemx --no-escape-from-lines
2967 @opindex escape-from-lines
2968 Because some mailers change lines starting with "From " to ">From " it
2969 is good to handle such lines in a special way when creating cleartext
2970 signatures to prevent the mail system from breaking the signature. Note
2971 that all other PGP versions do it this way too. Enabled by
2972 default. @option{--no-escape-from-lines} disables this option.
2974 @item --passphrase-repeat @code{n}
2975 @opindex passphrase-repeat
2976 Specify how many times @command{@gpgname} will request a new
2977 passphrase be repeated. This is useful for helping memorize a
2978 passphrase. Defaults to 1 repetition.
2980 @item --passphrase-fd @code{n}
2981 @opindex passphrase-fd
2982 Read the passphrase from file descriptor @code{n}. Only the first line
2983 will be read from file descriptor @code{n}. If you use 0 for @code{n},
2984 the passphrase will be read from STDIN. This can only be used if only
2985 one passphrase is supplied.
2987 Note that this passphrase is only used if the option @option{--batch}
2988 has also been given. This is different from GnuPG version 1.x.
2990 @item --passphrase-file @code{file}
2991 @opindex passphrase-file
2992 Read the passphrase from file @code{file}. Only the first line will
2993 be read from file @code{file}. This can only be used if only one
2994 passphrase is supplied. Obviously, a passphrase stored in a file is
2995 of questionable security if other users can read this file. Don't use
2996 this option if you can avoid it.
2997 Note that this passphrase is only used if the option @option{--batch}
2998 has also been given. This is different from GnuPG version 1.x.
3000 @item --passphrase @code{string}
3002 Use @code{string} as the passphrase. This can only be used if only one
3003 passphrase is supplied. Obviously, this is of very questionable
3004 security on a multi-user system. Don't use this option if you can
3006 Note that this passphrase is only used if the option @option{--batch}
3007 has also been given. This is different from GnuPG version 1.x.
3009 @item --pinentry-mode @code{mode}
3010 @opindex pinentry-mode
3011 Set the pinentry mode to @code{mode}. Allowed values for @code{mode}
3015 Use the default of the agent, which is @code{ask}.
3017 Force the use of the Pinentry.
3019 Emulate use of Pinentry's cancel button.
3021 Return a Pinentry error (``No Pinentry'').
3023 Redirect Pinentry queries to the caller. Note that in contrast to
3024 Pinentry the user is not prompted again if he enters a bad password.
3027 @item --command-fd @code{n}
3029 This is a replacement for the deprecated shared-memory IPC mode.
3030 If this option is enabled, user input on questions is not expected
3031 from the TTY but from the given file descriptor. It should be used
3032 together with @option{--status-fd}. See the file doc/DETAILS in the source
3033 distribution for details on how to use it.
3035 @item --command-file @code{file}
3036 @opindex command-file
3037 Same as @option{--command-fd}, except the commands are read out of file
3040 @item --allow-non-selfsigned-uid
3041 @itemx --no-allow-non-selfsigned-uid
3042 @opindex allow-non-selfsigned-uid
3043 Allow the import and use of keys with user IDs which are not
3044 self-signed. This is not recommended, as a non self-signed user ID is
3045 trivial to forge. @option{--no-allow-non-selfsigned-uid} disables.
3047 @item --allow-freeform-uid
3048 @opindex allow-freeform-uid
3049 Disable all checks on the form of the user ID while generating a new
3050 one. This option should only be used in very special environments as
3051 it does not ensure the de-facto standard format of user IDs.
3053 @item --ignore-time-conflict
3054 @opindex ignore-time-conflict
3055 GnuPG normally checks that the timestamps associated with keys and
3056 signatures have plausible values. However, sometimes a signature
3057 seems to be older than the key due to clock problems. This option
3058 makes these checks just a warning. See also @option{--ignore-valid-from} for
3059 timestamp issues on subkeys.
3061 @item --ignore-valid-from
3062 @opindex ignore-valid-from
3063 GnuPG normally does not select and use subkeys created in the future.
3064 This option allows the use of such keys and thus exhibits the
3065 pre-1.0.7 behaviour. You should not use this option unless there
3066 is some clock problem. See also @option{--ignore-time-conflict} for timestamp
3067 issues with signatures.
3069 @item --ignore-crc-error
3070 @opindex ignore-crc-error
3071 The ASCII armor used by OpenPGP is protected by a CRC checksum against
3072 transmission errors. Occasionally the CRC gets mangled somewhere on
3073 the transmission channel but the actual content (which is protected by
3074 the OpenPGP protocol anyway) is still okay. This option allows GnuPG
3075 to ignore CRC errors.
3077 @item --ignore-mdc-error
3078 @opindex ignore-mdc-error
3079 This option changes a MDC integrity protection failure into a warning.
3080 This can be useful if a message is partially corrupt, but it is
3081 necessary to get as much data as possible out of the corrupt message.
3082 However, be aware that a MDC protection failure may also mean that the
3083 message was tampered with intentionally by an attacker.
3085 @item --allow-weak-digest-algos
3086 @opindex allow-weak-digest-algos
3087 Signatures made with known-weak digest algorithms are normally
3088 rejected with an ``invalid digest algorithm'' message. This option
3089 allows the verification of signatures made with such weak algorithms.
3090 MD5 is the only digest algorithm considered weak by default. See also
3091 @option{--weak-digest} to reject other digest algorithms.
3093 @item --weak-digest @code{name}
3094 @opindex weak-digest
3095 Treat the specified digest algorithm as weak. Signatures made over
3096 weak digests algorithms are normally rejected. This option can be
3097 supplied multiple times if multiple algorithms should be considered
3098 weak. See also @option{--allow-weak-digest-algos} to disable
3099 rejection of weak digests. MD5 is always considered weak, and does
3100 not need to be listed explicitly.
3102 @item --no-default-keyring
3103 @opindex no-default-keyring
3104 Do not add the default keyrings to the list of keyrings. Note that
3105 GnuPG will not operate without any keyrings, so if you use this option
3106 and do not provide alternate keyrings via @option{--keyring} or
3107 @option{--secret-keyring}, then GnuPG will still use the default public or
3112 Do not add use any keyrings even if specified as options.
3115 @opindex skip-verify
3116 Skip the signature verification step. This may be
3117 used to make the decryption faster if the signature
3118 verification is not needed.
3120 @item --with-key-data
3121 @opindex with-key-data
3122 Print key listings delimited by colons (like @option{--with-colons}) and
3123 print the public key data.
3125 @item --fast-list-mode
3126 @opindex fast-list-mode
3127 Changes the output of the list commands to work faster; this is achieved
3128 by leaving some parts empty. Some applications don't need the user ID
3129 and the trust information given in the listings. By using this options
3130 they can get a faster listing. The exact behaviour of this option may
3131 change in future versions. If you are missing some information, don't
3136 This is not for normal use. Use the source to see for what it might be useful.
3138 @item --set-filesize
3139 @opindex set-filesize
3140 This is not for normal use. Use the source to see for what it might be useful.
3142 @item --show-session-key
3143 @opindex show-session-key
3144 Display the session key used for one message. See
3145 @option{--override-session-key} for the counterpart of this option.
3147 We think that Key Escrow is a Bad Thing; however the user should have
3148 the freedom to decide whether to go to prison or to reveal the content
3149 of one specific message without compromising all messages ever
3150 encrypted for one secret key.
3152 You can also use this option if you receive an encrypted message which
3153 is abusive or offensive, to prove to the administrators of the
3154 messaging system that the ciphertext transmitted corresponds to an
3155 inappropriate plaintext so they can take action against the offending
3158 @item --override-session-key @code{string}
3159 @itemx --override-session-key-fd @code{fd}
3160 @opindex override-session-key
3161 Don't use the public key but the session key @code{string} respective
3162 the session key taken from the first line read from file descriptor
3163 @code{fd}. The format of this string is the same as the one printed
3164 by @option{--show-session-key}. This option is normally not used but
3165 comes handy in case someone forces you to reveal the content of an
3166 encrypted message; using this option you can do this without handing
3167 out the secret key. Note that using @option{--override-session-key}
3168 may reveal the session key to all local users via the global process
3171 @item --ask-sig-expire
3172 @itemx --no-ask-sig-expire
3173 @opindex ask-sig-expire
3174 When making a data signature, prompt for an expiration time. If this
3175 option is not specified, the expiration time set via
3176 @option{--default-sig-expire} is used. @option{--no-ask-sig-expire}
3177 disables this option.
3179 @item --default-sig-expire
3180 @opindex default-sig-expire
3181 The default expiration time to use for signature expiration. Valid
3182 values are "0" for no expiration, a number followed by the letter d
3183 (for days), w (for weeks), m (for months), or y (for years) (for
3184 example "2m" for two months, or "5y" for five years), or an absolute
3185 date in the form YYYY-MM-DD. Defaults to "0".
3187 @item --ask-cert-expire
3188 @itemx --no-ask-cert-expire
3189 @opindex ask-cert-expire
3190 When making a key signature, prompt for an expiration time. If this
3191 option is not specified, the expiration time set via
3192 @option{--default-cert-expire} is used. @option{--no-ask-cert-expire}
3193 disables this option.
3195 @item --default-cert-expire
3196 @opindex default-cert-expire
3197 The default expiration time to use for key signature expiration.
3198 Valid values are "0" for no expiration, a number followed by the
3199 letter d (for days), w (for weeks), m (for months), or y (for years)
3200 (for example "2m" for two months, or "5y" for five years), or an
3201 absolute date in the form YYYY-MM-DD. Defaults to "0".
3203 @item --default-new-key-algo @var{string}
3204 @opindex default-new-key-algo @var{string}
3205 This option can be used to change the default algorithms for key
3206 generation. Note that the advanced key generation commands can always
3207 be used to specify a key algorithm directly. Please consult the
3208 source code to learn the syntax of @var{string}.
3210 @item --allow-secret-key-import
3211 @opindex allow-secret-key-import
3212 This is an obsolete option and is not used anywhere.
3214 @item --allow-multiple-messages
3215 @item --no-allow-multiple-messages
3216 @opindex allow-multiple-messages
3217 Allow processing of multiple OpenPGP messages contained in a single file
3218 or stream. Some programs that call GPG are not prepared to deal with
3219 multiple messages being processed together, so this option defaults to
3220 no. Note that versions of GPG prior to 1.4.7 always allowed multiple
3223 Warning: Do not use this option unless you need it as a temporary
3227 @item --enable-special-filenames
3228 @opindex enable-special-filenames
3229 This option enables a mode in which filenames of the form
3230 @file{-&n}, where n is a non-negative decimal number,
3231 refer to the file descriptor n and not to a file with that name.
3233 @item --no-expensive-trust-checks
3234 @opindex no-expensive-trust-checks
3235 Experimental use only.
3237 @item --preserve-permissions
3238 @opindex preserve-permissions
3239 Don't change the permissions of a secret keyring back to user
3240 read/write only. Use this option only if you really know what you are doing.
3242 @item --default-preference-list @code{string}
3243 @opindex default-preference-list
3244 Set the list of default preferences to @code{string}. This preference
3245 list is used for new keys and becomes the default for "setpref" in the
3248 @item --default-keyserver-url @code{name}
3249 @opindex default-keyserver-url
3250 Set the default keyserver URL to @code{name}. This keyserver will be
3251 used as the keyserver URL when writing a new self-signature on a key,
3252 which includes key generation and changing preferences.
3255 @opindex list-config
3256 Display various internal configuration parameters of GnuPG. This option
3257 is intended for external programs that call GnuPG to perform tasks, and
3258 is thus not generally useful. See the file @file{doc/DETAILS} in the
3259 source distribution for the details of which configuration items may be
3260 listed. @option{--list-config} is only usable with
3261 @option{--with-colons} set.
3263 @item --list-gcrypt-config
3264 @opindex list-gcrypt-config
3265 Display various internal configuration parameters of Libgcrypt.
3267 @item --gpgconf-list
3268 @opindex gpgconf-list
3269 This command is similar to @option{--list-config} but in general only
3270 internally used by the @command{gpgconf} tool.
3272 @item --gpgconf-test
3273 @opindex gpgconf-test
3274 This is more or less dummy action. However it parses the configuration
3275 file and returns with failure if the configuration file would prevent
3276 @command{@gpgname} from startup. Thus it may be used to run a syntax check
3277 on the configuration file.
3281 @c *******************************
3282 @c ******* Deprecated ************
3283 @c *******************************
3284 @node Deprecated Options
3285 @subsection Deprecated options
3290 @itemx --no-show-photos
3291 @opindex show-photos
3292 Causes @option{--list-keys}, @option{--list-signatures},
3293 @option{--list-public-keys}, @option{--list-secret-keys}, and verifying
3294 a signature to also display the photo ID attached to the key, if
3295 any. See also @option{--photo-viewer}. These options are deprecated. Use
3296 @option{--list-options [no-]show-photos} and/or @option{--verify-options
3297 [no-]show-photos} instead.
3299 @item --show-keyring
3300 @opindex show-keyring
3301 Display the keyring name at the head of key listings to show which
3302 keyring a given key resides on. This option is deprecated: use
3303 @option{--list-options [no-]show-keyring} instead.
3305 @item --always-trust
3306 @opindex always-trust
3307 Identical to @option{--trust-model always}. This option is deprecated.
3309 @item --show-notation
3310 @itemx --no-show-notation
3311 @opindex show-notation
3312 Show signature notations in the @option{--list-signatures} or @option{--check-signatures} listings
3313 as well as when verifying a signature with a notation in it. These
3314 options are deprecated. Use @option{--list-options [no-]show-notation}
3315 and/or @option{--verify-options [no-]show-notation} instead.
3317 @item --show-policy-url
3318 @itemx --no-show-policy-url
3319 @opindex show-policy-url
3320 Show policy URLs in the @option{--list-signatures} or @option{--check-signatures}
3321 listings as well as when verifying a signature with a policy URL in
3322 it. These options are deprecated. Use @option{--list-options
3323 [no-]show-policy-url} and/or @option{--verify-options
3324 [no-]show-policy-url} instead.
3330 @c *******************************************
3331 @c *************** ****************
3332 @c *************** FILES ****************
3333 @c *************** ****************
3334 @c *******************************************
3336 @node GPG Configuration
3337 @section Configuration files
3339 There are a few configuration files to control certain aspects of
3340 @command{@gpgname}'s operation. Unless noted, they are expected in the
3341 current home directory (@pxref{option --homedir}).
3347 This is the standard configuration file read by @command{@gpgname} on
3348 startup. It may contain any valid long option; the leading two dashes
3349 may not be entered and the option may not be abbreviated. This default
3350 name may be changed on the command line (@pxref{gpg-option --options}).
3351 You should backup this file.
3355 Note that on larger installations, it is useful to put predefined files
3356 into the directory @file{@value{SYSCONFSKELDIR}} so that
3357 newly created users start up with a working configuration.
3358 For existing users a small
3359 helper script is provided to create these files (@pxref{addgnupghome}).
3361 For internal purposes @command{@gpgname} creates and maintains a few other
3362 files; They all live in in the current home directory (@pxref{option
3363 --homedir}). Only the @command{@gpgname} program may modify these files.
3369 This is the default home directory which is used if neither the
3370 environment variable @code{GNUPGHOME} nor the option
3371 @option{--homedir} is given.
3373 @item ~/.gnupg/pubring.gpg
3374 @efindex pubring.gpg
3375 The public keyring. You should backup this file.
3377 @item ~/.gnupg/pubring.gpg.lock
3378 The lock file for the public keyring.
3380 @item ~/.gnupg/pubring.kbx
3381 @efindex pubring.kbx
3382 The public keyring using a different format. This file is shared
3383 with @command{gpgsm}. You should backup this file.
3385 @item ~/.gnupg/pubring.kbx.lock
3386 The lock file for @file{pubring.kbx}.
3388 @item ~/.gnupg/secring.gpg
3389 @efindex secring.gpg
3390 A secret keyring as used by GnuPG versions before 2.1. It is not
3391 used by GnuPG 2.1 and later.
3393 @item ~/.gnupg/secring.gpg.lock
3394 The lock file for the secret keyring.
3396 @item ~/.gnupg/.gpg-v21-migrated
3397 @efindex .gpg-v21-migrated
3398 File indicating that a migration to GnuPG 2.1 has been done.
3400 @item ~/.gnupg/trustdb.gpg
3401 @efindex trustdb.gpg
3402 The trust database. There is no need to backup this file; it is better
3403 to backup the ownertrust values (@pxref{option --export-ownertrust}).
3405 @item ~/.gnupg/trustdb.gpg.lock
3406 The lock file for the trust database.
3408 @item ~/.gnupg/random_seed
3409 @efindex random_seed
3410 A file used to preserve the state of the internal random pool.
3412 @item ~/.gnupg/openpgp-revocs.d/
3413 @efindex openpgp-revocs.d
3414 This is the directory where gpg stores pre-generated revocation
3415 certificates. The file name corresponds to the OpenPGP fingerprint of
3416 the respective key. It is suggested to backup those certificates and
3417 if the primary private key is not stored on the disk to move them to
3418 an external storage device. Anyone who can access theses files is
3419 able to revoke the corresponding key. You may want to print them out.
3420 You should backup all files in this directory and take care to keep
3421 this backup closed away.
3423 @item @value{DATADIR}/options.skel
3424 @efindex options.skel
3425 The skeleton options file.
3429 Operation is further controlled by a few environment variables:
3435 Used to locate the default home directory.
3439 If set directory used instead of "~/.gnupg".
3441 @item GPG_AGENT_INFO
3442 This variable is obsolete; it was used by GnuPG versions before 2.1.
3444 @item PINENTRY_USER_DATA
3445 @efindex PINENTRY_USER_DATA
3446 This value is passed via gpg-agent to pinentry. It is useful to convey
3447 extra information to a custom pinentry.
3453 Used to size some displays to the full size of the screen.
3457 Apart from its use by GNU, it is used in the W32 version to override the
3458 language selection done through the Registry. If used and set to a
3459 valid and available language name (@var{langid}), the file with the
3460 translation is loaded from
3461 @code{@var{gpgdir}/gnupg.nls/@var{langid}.mo}. Here @var{gpgdir} is the
3462 directory out of which the gpg binary has been loaded. If it can't be
3463 loaded the Registry is tried and as last resort the native Windows
3464 locale system is used.
3469 @c *******************************************
3470 @c *************** ****************
3471 @c *************** EXAMPLES ****************
3472 @c *************** ****************
3473 @c *******************************************
3480 @item gpg -se -r @code{Bob} @code{file}
3481 sign and encrypt for user Bob
3483 @item gpg --clear-sign @code{file}
3484 make a cleartext signature
3486 @item gpg -sb @code{file}
3487 make a detached signature
3489 @item gpg -u 0x12345678 -sb @code{file}
3490 make a detached signature with the key 0x12345678
3492 @item gpg --list-keys @code{user_ID}
3495 @item gpg --fingerprint @code{user_ID}
3498 @item gpg --verify @code{pgpfile}
3499 @itemx gpg --verify @code{sigfile} [@code{datafile}]
3500 Verify the signature of the file but do not output the data unless
3501 requested. The second form is used for detached signatures, where
3502 @code{sigfile} is the detached signature (either ASCII armored or
3503 binary) and @code{datafile} are the signed data; if this is not given, the name of the
3504 file holding the signed data is constructed by cutting off the
3505 extension (".asc" or ".sig") of @code{sigfile} or by asking the user
3506 for the filename. If the option @option{--output} is also used the
3507 signed data is written to the file specified by that option; use
3508 @code{-} to write the signed data to stdout.
3512 @c *******************************************
3513 @c *************** ****************
3514 @c *************** USER ID ****************
3515 @c *************** ****************
3516 @c *******************************************
3517 @mansect how to specify a user id
3519 @include specify-user-id.texi
3522 @mansect filter expressions
3523 @chapheading FILTER EXPRESSIONS
3525 The options @option{--import-filter} and @option{--export-filter} use
3526 expressions with this syntax (square brackets indicate an optional
3527 part and curly braces a repetition, white space between the elements
3532 [lc] @{[@{flag@}] PROPNAME op VALUE [lc]@}
3536 The name of a property (@var{PROPNAME}) may only consist of letters,
3537 digits and underscores. The description for the filter type
3538 describes which properties are defined. If an undefined property is
3539 used it evaluates to the empty string. Unless otherwise noted, the
3540 @var{VALUE} must always be given and may not be the empty string. No
3541 quoting is defined for the value, thus the value may not contain the
3542 strings @code{&&} or @code{||}, which are used as logical connection
3543 operators. The flag @code{--} can be used to remove this restriction.
3545 Numerical values are computed as long int; standard C notation
3546 applies. @var{lc} is the logical connection operator; either
3547 @code{&&} for a conjunction or @code{||} for a disjunction. A
3548 conjunction is assumed at the begin of an expression. Conjunctions
3549 have higher precedence than disjunctions. If @var{VALUE} starts with
3550 one of the characters used in any @var{op} a space after the
3551 @var{op} is required.
3554 The supported operators (@var{op}) are:
3559 Substring must match.
3562 Substring must not match.
3565 The full string must match.
3568 The full string must not match.
3571 The numerical value must match.
3574 The numerical value must not match.
3577 The numerical value of the field must be LE than the value.
3580 The numerical value of the field must be LT than the value.
3583 The numerical value of the field must be GT than the value.
3586 The numerical value of the field must be GE than the value.
3589 The string value of the field must be less or equal than the value.
3592 The string value of the field must be less than the value.
3595 The string value of the field must be greater than the value.
3598 The string value of the field must be greater or equal than the value.
3601 True if value is not empty (no value allowed).
3604 True if value is empty (no value allowed).
3607 Alias for "PROPNAME != 0" (no value allowed).
3610 Alias for "PROPNAME == 0" (no value allowed).
3615 Values for @var{flag} must be space separated. The supported flags
3620 @var{VALUE} spans to the end of the expression.
3622 The string match in this part is done case-sensitive.
3625 The filter options concatenate several specifications for a filter of
3626 the same type. For example the four options in this example:
3630 --import-option keep-uid="uid =~ Alfa"
3631 --import-option keep-uid="&& uid !~ Test"
3632 --import-option keep-uid="|| uid =~ Alpha"
3633 --import-option keep-uid="uid !~ Test"
3638 which is equivalent to
3643 keep-uid="uid =~ Alfa" && uid !~ Test" || uid =~ Alpha" && "uid !~ Test"
3647 imports only the user ids of a key containing the strings "Alfa"
3648 or "Alpha" but not the string "test".
3651 @mansect return value
3652 @chapheading RETURN VALUE
3654 The program returns 0 if everything was fine, 1 if at least
3655 a signature was bad, and other error codes for fatal errors.
3658 @chapheading WARNINGS
3660 Use a *good* password for your user account and a *good* passphrase
3661 to protect your secret key. This passphrase is the weakest part of the
3662 whole system. Programs to do dictionary attacks on your secret keyring
3663 are very easy to write and so you should protect your "~/.gnupg/"
3664 directory very well.
3666 Keep in mind that, if this program is used over a network (telnet), it
3667 is *very* easy to spy out your passphrase!
3669 If you are going to verify detached signatures, make sure that the
3670 program knows about it; either give both filenames on the command line
3671 or use @samp{-} to specify STDIN.
3673 @mansect interoperability
3674 @chapheading INTEROPERABILITY WITH OTHER OPENPGP PROGRAMS
3676 GnuPG tries to be a very flexible implementation of the OpenPGP
3677 standard. In particular, GnuPG implements many of the optional parts
3678 of the standard, such as the SHA-512 hash, and the ZLIB and BZIP2
3679 compression algorithms. It is important to be aware that not all
3680 OpenPGP programs implement these optional algorithms and that by
3681 forcing their use via the @option{--cipher-algo},
3682 @option{--digest-algo}, @option{--cert-digest-algo}, or
3683 @option{--compress-algo} options in GnuPG, it is possible to create a
3684 perfectly valid OpenPGP message, but one that cannot be read by the
3687 There are dozens of variations of OpenPGP programs available, and each
3688 supports a slightly different subset of these optional algorithms.
3689 For example, until recently, no (unhacked) version of PGP supported
3690 the BLOWFISH cipher algorithm. A message using BLOWFISH simply could
3691 not be read by a PGP user. By default, GnuPG uses the standard
3692 OpenPGP preferences system that will always do the right thing and
3693 create messages that are usable by all recipients, regardless of which
3694 OpenPGP program they use. Only override this safe default if you
3695 really know what you are doing.
3697 If you absolutely must override the safe default, or if the preferences
3698 on a given key are invalid for some reason, you are far better off using
3699 the @option{--pgp6}, @option{--pgp7}, or @option{--pgp8} options. These
3700 options are safe as they do not force any particular algorithms in
3701 violation of OpenPGP, but rather reduce the available algorithms to a
3707 On older systems this program should be installed as setuid(root). This
3708 is necessary to lock memory pages. Locking memory pages prevents the
3709 operating system from writing memory pages (which may contain
3710 passphrases or other sensitive material) to disk. If you get no
3711 warning message about insecure memory your operating system supports
3712 locking without being root. The program drops root privileges as soon
3713 as locked memory is allocated.
3715 Note also that some systems (especially laptops) have the ability to
3716 ``suspend to disk'' (also known as ``safe sleep'' or ``hibernate'').
3717 This writes all memory to disk before going into a low power or even
3718 powered off mode. Unless measures are taken in the operating system
3719 to protect the saved memory, passphrases or other sensitive material
3720 may be recoverable from it later.
3722 Before you report a bug you should first search the mailing list
3723 archives for similar problems and second check whether such a bug has
3724 already been reported to our bug tracker at http://bugs.gnupg.org .
3726 @c *******************************************
3727 @c *************** **************
3728 @c *************** UNATTENDED **************
3729 @c *************** **************
3730 @c *******************************************
3732 @node Unattended Usage of GPG
3733 @section Unattended Usage
3735 @command{@gpgname} is often used as a backend engine by other software. To help
3736 with this a machine interface has been defined to have an unambiguous
3737 way to do this. The options @option{--status-fd} and @option{--batch}
3738 are almost always required for this.
3741 * Programmatic use of GnuPG:: Programmatic use of GnuPG
3742 * Ephemeral home directories:: Ephemeral home directories
3743 * The quick key manipulation interface:: The quick key manipulation interface
3744 * Unattended GPG key generation:: Unattended key generation
3748 @node Programmatic use of GnuPG
3749 @subsection Programmatic use of GnuPG
3751 Please consider using GPGME instead of calling @command{@gpgname}
3752 directly. GPGME offers a stable, backend-independent interface for
3753 many cryptographic operations. It supports OpenPGP and S/MIME, and
3754 also allows interaction with various GnuPG components.
3756 GPGME provides a C-API, and comes with bindings for C++, Qt, and
3757 Python. Bindings for other languages are available.
3759 @node Ephemeral home directories
3760 @subsection Ephemeral home directories
3762 Sometimes you want to contain effects of some operation, for example
3763 you want to import a key to inspect it, but you do not want this key
3764 to be added to your keyring. In earlier versions of GnuPG, it was
3765 possible to specify alternate keyring files for both public and secret
3766 keys. In modern GnuPG versions, however, we changed how secret keys
3767 are stored in order to better protect secret key material, and it was
3768 not possible to preserve this interface.
3770 The preferred way to do this is to use ephemeral home directories.
3771 This technique works across all versions of GnuPG.
3773 Create a temporary directory, create (or copy) a configuration that
3774 meets your needs, make @command{@gpgname} use this directory either
3775 using the environment variable @var{GNUPGHOME}, or the option
3776 @option{--homedir}. GPGME supports this too on a per-context basis,
3777 by modifying the engine info of contexts. Now execute whatever
3778 operation you like, import and export key material as necessary. Once
3779 finished, you can delete the directory. All GnuPG backend services
3780 that were started will detect this and shut down.
3782 @node The quick key manipulation interface
3783 @subsection The quick key manipulation interface
3785 Recent versions of GnuPG have an interface to manipulate keys without
3786 using the interactive command @option{--edit-key}. This interface was
3787 added mainly for the benefit of GPGME (please consider using GPGME,
3788 see the manual subsection ``Programmatic use of GnuPG''). This
3789 interface is described in the subsection ``How to manage your keys''.
3791 @node Unattended GPG key generation
3792 @subsection Unattended key generation
3794 The command @option{--generate-key} may be used along with the option
3795 @option{--batch} for unattended key generation. This is the most
3796 flexible way of generating keys, but it is also the most complex one.
3797 Consider using the quick key manipulation interface described in the
3798 previous subsection ``The quick key manipulation interface''.
3800 The parameters for the key are either read from stdin or given as a
3801 file on the command line. The format of the parameter file is as
3805 @item Text only, line length is limited to about 1000 characters.
3806 @item UTF-8 encoding must be used to specify non-ASCII characters.
3807 @item Empty lines are ignored.
3808 @item Leading and trailing while space is ignored.
3809 @item A hash sign as the first non white space character indicates
3811 @item Control statements are indicated by a leading percent sign, the
3812 arguments are separated by white space from the keyword.
3813 @item Parameters are specified by a keyword, followed by a colon. Arguments
3814 are separated by white space.
3816 The first parameter must be @samp{Key-Type}; control statements may be
3819 The order of the parameters does not matter except for @samp{Key-Type}
3820 which must be the first parameter. The parameters are only used for
3821 the generated keyblock (primary and subkeys); parameters from previous
3822 sets are not used. Some syntactically checks may be performed.
3824 Key generation takes place when either the end of the parameter file
3825 is reached, the next @samp{Key-Type} parameter is encountered or at the
3826 control statement @samp{%commit} is encountered.
3834 @item %echo @var{text}
3835 Print @var{text} as diagnostic.
3838 Suppress actual key generation (useful for syntax checking).
3841 Perform the key generation. Note that an implicit commit is done at
3842 the next @asis{Key-Type} parameter.
3844 @item %pubring @var{filename}
3845 Do not write the key to the default or commandline given keyring but
3846 to @var{filename}. This must be given before the first commit to take
3847 place, duplicate specification of the same filename is ignored, the
3848 last filename before a commit is used. The filename is used until a
3849 new filename is used (at commit points) and all keys are written to
3850 that file. If a new filename is given, this file is created (and
3851 overwrites an existing one).
3853 See the previous subsection ``Ephemeral home directories'' for a more
3854 robust way to contain side-effects.
3856 @item %secring @var{filename}
3857 This option is a no-op for GnuPG 2.1 and later.
3859 See the previous subsection ``Ephemeral home directories''.
3861 @item %ask-passphrase
3862 @itemx %no-ask-passphrase
3863 This option is a no-op for GnuPG 2.1 and later.
3865 @item %no-protection
3866 Using this option allows the creation of keys without any passphrase
3867 protection. This option is mainly intended for regression tests.
3869 @item %transient-key
3870 If given the keys are created using a faster and a somewhat less
3871 secure random number generator. This option may be used for keys
3872 which are only used for a short time and do not require full
3873 cryptographic strength. It takes only effect if used together with
3874 the control statement @samp{%no-protection}.
3883 @item Key-Type: @var{algo}
3884 Starts a new parameter block by giving the type of the primary
3885 key. The algorithm must be capable of signing. This is a required
3886 parameter. @var{algo} may either be an OpenPGP algorithm number or a
3887 string with the algorithm name. The special value @samp{default} may
3888 be used for @var{algo} to create the default key type; in this case a
3889 @samp{Key-Usage} shall not be given and @samp{default} also be used
3890 for @samp{Subkey-Type}.
3892 @item Key-Length: @var{nbits}
3893 The requested length of the generated key in bits. The default is
3894 returned by running the command @samp{@gpgname --gpgconf-list}.
3896 @item Key-Grip: @var{hexstring}
3897 This is optional and used to generate a CSR or certificate for an
3898 already existing key. Key-Length will be ignored when given.
3900 @item Key-Usage: @var{usage-list}
3901 Space or comma delimited list of key usages. Allowed values are
3902 @samp{encrypt}, @samp{sign}, and @samp{auth}. This is used to
3903 generate the key flags. Please make sure that the algorithm is
3904 capable of this usage. Note that OpenPGP requires that all primary
3905 keys are capable of certification, so no matter what usage is given
3906 here, the @samp{cert} flag will be on. If no @samp{Key-Usage} is
3907 specified and the @samp{Key-Type} is not @samp{default}, all allowed
3908 usages for that particular algorithm are used; if it is not given but
3909 @samp{default} is used the usage will be @samp{sign}.
3911 @item Subkey-Type: @var{algo}
3912 This generates a secondary key (subkey). Currently only one subkey
3913 can be handled. See also @samp{Key-Type} above.
3915 @item Subkey-Length: @var{nbits}
3916 Length of the secondary key (subkey) in bits. The default is returned
3917 by running the command @samp{@gpgname --gpgconf-list}.
3919 @item Subkey-Usage: @var{usage-list}
3920 Key usage lists for a subkey; similar to @samp{Key-Usage}.
3922 @item Passphrase: @var{string}
3923 If you want to specify a passphrase for the secret key, enter it here.
3924 Default is to use the Pinentry dialog to ask for a passphrase.
3926 @item Name-Real: @var{name}
3927 @itemx Name-Comment: @var{comment}
3928 @itemx Name-Email: @var{email}
3929 The three parts of a user name. Remember to use UTF-8 encoding here.
3930 If you don't give any of them, no user ID is created.
3932 @item Expire-Date: @var{iso-date}|(@var{number}[d|w|m|y])
3933 Set the expiration date for the key (and the subkey). It may either
3934 be entered in ISO date format (e.g. "20000815T145012") or as number of
3935 days, weeks, month or years after the creation date. The special
3936 notation "seconds=N" is also allowed to specify a number of seconds
3937 since creation. Without a letter days are assumed. Note that there
3938 is no check done on the overflow of the type used by OpenPGP for
3939 timestamps. Thus you better make sure that the given value make
3940 sense. Although OpenPGP works with time intervals, GnuPG uses an
3941 absolute value internally and thus the last year we can represent is
3944 @item Creation-Date: @var{iso-date}
3945 Set the creation date of the key as stored in the key information and
3946 which is also part of the fingerprint calculation. Either a date like
3947 "1986-04-26" or a full timestamp like "19860426T042640" may be used.
3948 The time is considered to be UTC. The special notation "seconds=N"
3949 may be used to directly specify a the number of seconds since Epoch
3950 (Unix time). If it is not given the current time is used.
3952 @item Preferences: @var{string}
3953 Set the cipher, hash, and compression preference values for this key.
3954 This expects the same type of string as the sub-command @samp{setpref}
3955 in the @option{--edit-key} menu.
3957 @item Revoker: @var{algo}:@var{fpr} [sensitive]
3958 Add a designated revoker to the generated key. Algo is the public key
3959 algorithm of the designated revoker (i.e. RSA=1, DSA=17, etc.)
3960 @var{fpr} is the fingerprint of the designated revoker. The optional
3961 @samp{sensitive} flag marks the designated revoker as sensitive
3962 information. Only v4 keys may be designated revokers.
3964 @item Keyserver: @var{string}
3965 This is an optional parameter that specifies the preferred keyserver
3968 @item Handle: @var{string}
3969 This is an optional parameter only used with the status lines
3970 KEY_CREATED and KEY_NOT_CREATED. @var{string} may be up to 100
3971 characters and should not contain spaces. It is useful for batch key
3972 generation to associate a key parameter block with a status line.
3977 Here is an example on how to create a key in an ephemeral home directory:
3979 $ export GNUPGHOME="$(mktemp -d)"
3981 %echo Generating a basic OpenPGP key
3986 Name-Real: Joe Tester
3987 Name-Comment: with stupid passphrase
3988 Name-Email: joe@@foo.bar
3991 # Do a commit here, so that we can later print "done" :-)
3995 $ @gpgname --batch --generate-key foo
3997 $ @gpgname --list-secret-keys
3998 /tmp/tmp.0NQxB74PEf/pubring.kbx
3999 -------------------------------
4000 sec dsa1024 2016-12-16 [SCA]
4001 768E895903FC1C44045C8CB95EEBDB71E9E849D0
4002 uid [ultimate] Joe Tester (with stupid passphrase) <joe@@foo.bar>
4003 ssb elg1024 2016-12-16 [E]
4007 If you want to create a key with the default algorithms you would use
4010 %echo Generating a default key
4012 Subkey-Type: default
4013 Name-Real: Joe Tester
4014 Name-Comment: with stupid passphrase
4015 Name-Email: joe@@foo.bar
4018 # Do a commit here, so that we can later print "done" :-)
4030 @command{gpg-agent}(1)
4032 @include see-also-note.texi