8
9
@cindex command options
9
10
@cindex options, GPG command
11
@c man begin DESCRIPTION
13
@command{gpg} is the OpenPGP part of GnuPG. The version included in
14
this package is not as matured as the standard versions (1.2.x or
15
1.4.x) and thus we strongly suggest to keep on using the one of the
16
standard versions. Both versions may be installed side by side and
17
should coexists without problems. To help for that, the @command{gpg}
18
from this package gets installed under the name @command{gpg2}. If you
19
really want to use this @command{gpg2} command you should name the
20
configuration file @file{gpg.conf-1.9} to keep it separate from the
21
one used with the standard @command{gpg}.
23
Documentation for the old standard @command{gpg} is available in a
24
man page and at @inforef{Top,GnuPG 1,gpg}.
12
@c Begin GnuPG 1.x specific stuff
20
\- OpenPGP encryption and signing tool
35
@c End GnuPG 1.x specific stuff
37
@c Begin GnuPG 2 specific stuff
45
\- OpenPGP encryption and signing tool
60
@c Begin GnuPG 2 specific stuff
63
@command{@gpgname} is the OpenPGP part of the GNU Privacy Guard (GnuPG). It
64
is a tool to provide digital encryption and signing services using the
65
OpenPGP standard. @command{@gpgname} features complete key management and
66
all bells and whistles you can expect from a decent OpenPGP
70
This is the standalone version of @command{gpg}. For desktop use you
71
should consider using @command{gpg2}.
75
In contrast to the standalone version @command{gpg}, which is more
76
suited for server and embedded platforms, this version is installed
77
under the name @command{gpg2} and more targeted to the desktop as it
78
requires several other modules to be installed. The standalone version
79
will be kept maintained and it is possible to install both versions on
80
the same system. If you need to use different configuration files, you
81
should make use of something like @file{gpg.conf-2} instead of just
87
Documentation for the old standard @command{gpg} is available as a man
88
page and at @inforef{Top,GnuPG 1,gpg}.
91
@xref{Option Index}, for an index to @command{@gpgname}'s commands and options.
95
* GPG Commands:: List of all commands.
96
* GPG Options:: List of all options.
97
* GPG Configuration:: Configuration files.
98
* GPG Examples:: Some usage examples.
100
Developer information:
101
@c * Unattended Usage:: Using @command{gpg} from other programs.
102
@c * GPG Protocol:: The protocol the server mode uses.
107
@c *******************************************
108
@c *************** ****************
109
@c *************** COMMANDS ****************
110
@c *************** ****************
111
@c *******************************************
116
Commands are not distinguished from options except for the fact that
117
only one command is allowed.
119
@command{@gpgname} may be run with no commands, in which case it will
120
perform a reasonable action depending on the type of file it is given
121
as input (an encrypted message is decrypted, a signature is verified,
122
a file containing keys is listed).
124
Please remember that option as well as command parsing stops as soon as
125
a non-option is encountered, you can explicitly stop parsing by
126
using the special option @option{--}.
130
* General GPG Commands:: Commands not specific to the functionality.
131
* Operational GPG Commands:: Commands to select the type of operation.
132
* OpenPGP Key Management:: How to manage your keys.
136
@c *******************************************
137
@c ********** GENERAL COMMANDS *************
138
@c *******************************************
139
@node General GPG Commands
140
@subsection Commands not specific to the function
145
Print the program version and licensing information. Note that you
146
cannot abbreviate this command.
151
Print a usage message summarizing the most useful command line options.
152
Not that you cannot abbreviate this command.
156
Print warranty information.
159
@opindex dump-options
160
Print a list of all available options and commands. Note that you cannot
161
abbreviate this command.
165
@c *******************************************
166
@c ******** OPERATIONAL COMMANDS ***********
167
@c *******************************************
168
@node Operational GPG Commands
169
@subsection Commands to select the type of operation
177
Make a signature. This command may be combined with @option{--encrypt}
178
(for a signed and encrypted message), @option{--symmetric} (for a signed
179
and symmetrically encrypted message), or @option{--encrypt} and
180
@option{--symmetric} together (for a signed message that may be
181
decrypted via a secret key or a passphrase).
185
Make a clear text signature. The content in a clear text signature is
186
readable without any special software. OpenPGP software is only
187
needed to verify the signature. Clear text signatures may modify
188
end-of-line whitespace for platform independence and are not intended
194
Make a detached signature.
199
Encrypt data. This option may be combined with @option{--sign} (for a
200
signed and encrypted message), @option{--symmetric} (for a message that
201
may be decrypted via a secret key or a passphrase), or @option{--sign}
202
and @option{--symmetric} together (for a signed message that may be
203
decrypted via a secret key or a passphrase).
208
Encrypt with a symmetric cipher using a passphrase. The default
209
symmetric cipher used is CAST5, but may be chosen with the
210
@option{--cipher-algo} option. This option may be combined with
211
@option{--sign} (for a signed and symmetrically encrypted message),
212
@option{--encrypt} (for a message that may be decrypted via a secret key
213
or a passphrase), or @option{--sign} and @option{--encrypt} together
214
(for a signed message that may be decrypted via a secret key or a
219
Store only (make a simple RFC1991 literal data packet).
224
Decrypt the file given on the command line (or @code{stdin} if no file
225
is specified) and write it to stdout (or the file specified with
226
@option{--output}). If the decrypted file is signed, the signature is also
227
verified. This command differs from the default operation, as it never
228
writes to the filename which is included in the file and it rejects
229
files which don't begin with an encrypted message.
233
Assume that the first argument is a signed file or a detached signature
234
and verify it without generating any output. With no arguments, the
235
signature packet is read from stdin. If only a sigfile is given, it may
236
be a complete signature or a detached signature, in which case the
237
signed stuff is expected in a file without the ".sig" or ".asc"
238
extension. With more than 1 argument, the first should be a detached
239
signature and the remaining files are the signed stuff. To read the
240
signed stuff from stdin, use @samp{-} as the second filename. For
241
security reasons a detached signature cannot read the signed material
242
from stdin without denoting it in the above way.
246
This modifies certain other commands to accept multiple files for
247
processing on the command line or read from stdin with each filename on
248
a separate line. This allows for many files to be processed at
249
once. @option{--multifile} may currently be used along with
250
@option{--verify}, @option{--encrypt}, and @option{--decrypt}. Note that
251
@option{--multifile --verify} may not be used with detached signatures.
254
@opindex verify-files
255
Identical to @option{--multifile --verify}.
257
@item --encrypt-files
258
@opindex encrypt-files
259
Identical to @option{--multifile --encrypt}.
261
@item --decrypt-files
262
@opindex decrypt-files
263
Identical to @option{--multifile --decrypt}.
267
@itemx --list-public-keys
269
List all keys from the public keyrings, or just the keys given on the
272
@option{-k} is slightly different from @option{--list-keys} in that it
273
allows only for one argument and takes the second argument as the
274
keyring to search. This is for command line compatibility with PGP 2
275
and has been removed in @command{gpg2}.
278
Avoid using the output of this command in scripts or other programs as
279
it is likely to change as GnuPG changes. See @option{--with-colons} for a
280
machine-parseable key listing command that is appropriate for use in
281
scripts and other programs.
283
@item --list-secret-keys
285
@opindex list-secret-keys
286
List all keys from the secret keyrings, or just the ones given on the
287
command line. A @code{#} after the letters @code{sec} means that the
288
secret key is not usable (for example, if it was created via
289
@option{--export-secret-subkeys}).
293
Same as @option{--list-keys}, but the signatures are listed too.
295
For each signature listed, there are several flags in between the "sig"
296
tag and keyid. These flags give additional information about each
297
signature. From left to right, they are the numbers 1-3 for certificate
298
check level (see @option{--ask-cert-level}), "L" for a local or
299
non-exportable signature (see @option{--lsign-key}), "R" for a
300
nonRevocable signature (see the @option{--edit-key} command "nrsign"),
301
"P" for a signature that contains a policy URL (see
302
@option{--cert-policy-url}), "N" for a signature that contains a
303
notation (see @option{--cert-notation}), "X" for an eXpired signature
304
(see @option{--ask-cert-expire}), and the numbers 1-9 or "T" for 10 and
305
above to indicate trust signature levels (see the @option{--edit-key}
310
Same as @option{--list-sigs}, but the signatures are verified.
312
The status of the verification is indicated by a flag directly following
313
the "sig" tag (and thus before the flags described above for
314
@option{--list-sigs}). A "!" indicates that the signature has been
315
successfully verified, a "-" denotes a bad signature and a "%" is used
316
if an error occured while checking the signature (e.g. a non supported
322
List all keys (or the specified ones) along with their
323
fingerprints. This is the same output as @option{--list-keys} but with
324
the additional output of a line with the fingerprint. May also be
325
combined with @option{--list-sigs} or @option{--check-sigs}. If this
326
command is given twice, the fingerprints of all secondary keys are
330
@opindex list-packets
331
List only the sequence of packets. This is mainly
332
useful for debugging.
337
Present a menu to work with a smartcard. The subcommand "help" provides
338
an overview on available commands. For a detailed description, please
339
see the Card HOWTO at
340
http://www.gnupg.org/documentation/howtos.html#GnuPG-cardHOWTO .
344
Show the content of the smart card.
348
Present a menu to allow changing the PIN of a smartcard. This
349
functionality is also available as the subcommand "passwd" with the
350
@option{--card-edit} command.
352
@item --delete-key @code{name}
354
Remove key from the public keyring. In batch mode either @option{--yes} is
355
required or the key must be specified by fingerprint. This is a
356
safeguard against accidental deletion of multiple keys.
358
@item --delete-secret-key @code{name}
359
@opindex delete-secret-key
360
Remove key from the secret and public keyring. In batch mode the key
361
must be specified by fingerprint.
363
@item --delete-secret-and-public-key @code{name}
364
@opindex delete-secret-and-public-key
365
Same as @option{--delete-key}, but if a secret key exists, it will be
366
removed first. In batch mode the key must be specified by fingerprint.
370
Either export all keys from all keyrings (default keyrings and those
371
registered via option @option{--keyring}), or if at least one name is given,
372
those of the given name. The new keyring is written to stdout or to the
373
file given with option @option{--output}. Use together with
374
@option{--armor} to mail those keys.
376
@item --send-keys @code{key IDs}
378
Similar to @option{--export} but sends the keys to a keyserver.
379
Fingerprints may be used instead of key IDs. Option @option{--keyserver}
380
must be used to give the name of this keyserver. Don't send your
381
complete keyring to a keyserver --- select only those keys which are new
384
@item --export-secret-keys
385
@itemx --export-secret-subkeys
386
@opindex export-secret-keys
387
@opindex export-secret-subkeys
388
Same as @option{--export}, but exports the secret keys instead. This is
389
normally not very useful and a security risk. The second form of the
390
command has the special property to render the secret part of the
391
primary key useless; this is a GNU extension to OpenPGP and other
392
implementations can not be expected to successfully import such a key.
393
See the option @option{--simple-sk-checksum} if you want to import such
394
an exported key with an older OpenPGP implementation.
399
Import/merge keys. This adds the given keys to the
400
keyring. The fast version is currently just a synonym.
402
There are a few other options which control how this command works.
403
Most notable here is the @option{--keyserver-options merge-only} option
404
which does not insert new keys but does only the merging of new
405
signatures, user-IDs and subkeys.
407
@item --recv-keys @code{key IDs}
409
Import the keys with the given key IDs from a keyserver. Option
410
@option{--keyserver} must be used to give the name of this keyserver.
413
@opindex refresh-keys
414
Request updates from a keyserver for keys that already exist on the
415
local keyring. This is useful for updating a key with the latest
416
signatures, user IDs, etc. Calling this with no arguments will refresh
417
the entire keyring. Option @option{--keyserver} must be used to give the
418
name of the keyserver for all keys that do not have preferred keyservers
419
set (see @option{--keyserver-options honor-keyserver-url}).
421
@item --search-keys @code{names}
423
Search the keyserver for the given names. Multiple names given here will
424
be joined together to create the search string for the keyserver.
425
Option @option{--keyserver} must be used to give the name of this
426
keyserver. Keyservers that support different search methods allow using
427
the syntax specified in "How to specify a user ID" below. Note that
428
different keyserver types support different search methods. Currently
429
only LDAP supports them all.
431
@item --fetch-keys @code{URIs}
433
Retrieve keys located at the specified URIs. Note that different
434
installations of GnuPG may support different protocols (HTTP, FTP,
437
@item --update-trustdb
438
@opindex update-trustdb
439
Do trust database maintenance. This command iterates over all keys and
440
builds the Web of Trust. This is an interactive command because it may
441
have to ask for the "ownertrust" values for keys. The user has to give
442
an estimation of how far she trusts the owner of the displayed key to
443
correctly certify (sign) other keys. GnuPG only asks for the ownertrust
444
value if it has not yet been assigned to a key. Using the
445
@option{--edit-key} menu, the assigned value can be changed at any time.
447
@item --check-trustdb
448
@opindex check-trustdb
449
Do trust database maintenance without user interaction. From time to
450
time the trust database must be updated so that expired keys or
451
signatures and the resulting changes in the Web of Trust can be
452
tracked. Normally, GnuPG will calculate when this is required and do it
453
automatically unless @option{--no-auto-check-trustdb} is set. This
454
command can be used to force a trust database check at any time. The
455
processing is identical to that of @option{--update-trustdb} but it
456
skips keys with a not yet defined "ownertrust".
458
For use with cron jobs, this command can be used together with
459
@option{--batch} in which case the trust database check is done only if
460
a check is needed. To force a run even in batch mode add the option
463
@item --export-ownertrust
464
@opindex export-ownertrust
465
Send the ownertrust values to stdout. This is useful for backup purposes
466
as these values are the only ones which can't be re-created from a
469
@item --import-ownertrust
470
@opindex import-ownertrust
471
Update the trustdb with the ownertrust values stored in @code{files} (or
472
stdin if not given); existing values will be overwritten.
474
@item --rebuild-keydb-caches
475
@opindex rebuild-keydb-caches
476
When updating from version 1.0.6 to 1.0.7 this command should be used
477
to create signature caches in the keyring. It might be handy in other
480
@item --print-md @code{algo}
483
Print message digest of algorithm ALGO for all given files or stdin.
484
With the second form (or a deprecated "*" as algo) digests for all
485
available algorithms are printed.
487
@item --gen-random @code{0|1|2}
489
Emit @var{count} random bytes of the given quality level. If count is
490
not given or zero, an endless sequence of random bytes will be emitted.
491
PLEASE, don't use this command unless you know what you are doing; it
492
may remove precious entropy from the system!
494
@item --gen-prime @code{mode} @code{bits}
496
Use the source, Luke :-). The output format is still subject to change.
503
Pack or unpack an arbitrary input into/from an OpenPGP ASCII armor.
504
This is a GnuPG extension to OpenPGP and in general not very useful.
509
@c *******************************************
510
@c ******* KEY MANGEMENT COMMANDS **********
511
@c *******************************************
512
@node OpenPGP Key Management
513
@subsection How to manage your keys
515
This section explains the main commands for key management
521
Generate a new key pair. This command is normally only used
524
There is an experimental feature which allows you to create keys in
525
batch mode. See the file @file{doc/DETAILS} in the source distribution
528
@item --gen-revoke @code{name}
530
Generate a revocation certificate for the complete key. To revoke
531
a subkey or a signature, use the @option{--edit} command.
533
@item --desig-revoke @code{name}
534
@opindex desig-revoke
535
Generate a designated revocation certificate for a key. This allows a
536
user (with the permission of the keyholder) to revoke someone else's
542
Present a menu which enables you to do most of the key management
543
related tasks. It expects the specification of a key on the command
546
@c ******** Begin Edit-key Options **********
550
@opindex keyedit:sign
551
Make a signature on key of user @code{name} If the key is not yet
552
signed by the default user (or the users given with -u), the program
553
displays the information of the key again, together with its
554
fingerprint and asks whether it should be signed. This question is
555
repeated for all users specified with
559
@opindex keyedit:lsign
560
Same as "sign" but the signature is marked as non-exportable and will
561
therefore never be used by others. This may be used to make keys
562
valid only in the local environment.
565
@opindex keyedit:nrsign
566
Same as "sign" but the signature is marked as non-revocable and can
567
therefore never be revoked.
570
@opindex keyedit:tsign
571
Make a trust signature. This is a signature that combines the notions
572
of certification (like a regular signature), and trust (like the
573
"trust" command). It is generally only useful in distinct communities
578
Note that "l" (for local / non-exportable), "nr" (for non-revocable,
579
and "t" (for trust) may be freely mixed and prefixed to "sign" to
580
create a signature of any type desired.
586
@opindex keyedit:revsig
587
Revoke a signature. For every signature which has been generated by
588
one of the secret keys, GnuPG asks whether a revocation certificate
592
@opindex keyedit:trust
593
Change the owner trust value. This updates the
594
trust-db immediately and no save is required.
598
@opindex keyedit:disable
599
@opindex keyedit:enable
600
Disable or enable an entire key. A disabled key can not normally be
604
@opindex keyedit:adduid
605
Create an alternate user id.
608
@opindex keyedit:addphoto
609
Create a photographic user id. This will prompt for a JPEG file that
610
will be embedded into the user ID. Note that a very large JPEG will make
611
for a very large key. Also note that some programs will display your
612
JPEG unchanged (GnuPG), and some programs will scale it to fit in a
616
@opindex keyedit:deluid
617
Delete a user id. Note that it is not possible to retract a user id,
618
once it has been send to the public (i.e. to a keyserver). In that case
619
you better use @code{revuid}.
622
@opindex keyedit:delsig
623
Delete a signature. Note that it is not possible to retract a signature,
624
once it has been send to the public (i.e. to a keyserver). In that case
625
you better use @code{revsig}.
628
@opindex keyedit:revuid
632
@opindex keyedit:addkey
633
Add a subkey to this key.
636
@opindex keyedit:addcardkey
637
Generate a key on a card and add it to this key.
640
@opindex keyedit:keytocard
641
Transfer the selected secret key (or the primary key if no key has been
642
selected) to a smartcard. The secret key in the keyring will be replaced
643
by a stub if the key could be stored successfully on the card and you
644
use the save command later. Only certain key types may be transferred to
645
the card. A sub menu allows you to select on what card to store the
646
key. Note that it is not possible to get that key back from the card -
647
if the card gets broken your secret key will be lost unless you have a
650
@item bkuptocard @code{file}
651
@opindex keyedit:bkuptocard
652
Restore the given file to a card. This command may be used to restore a
653
backup key (as generated during card initialization) to a new card. In
654
almost all cases this will be the encryption key. You should use this
655
command only with the corresponding public key and make sure that the
656
file given as argument is indeed the backup to restore. You should then
657
select 2 to restore as encryption key. You will first be asked to enter
658
the passphrase of the backup key and then for the Admin PIN of the card.
661
@opindex keyedit:delkey
662
Remove a subkey (secondart key). Note that it is not possible to retract
663
a subkey, once it has been send to the public (i.e. to a keyserver). In
664
that case you better use @code{revkey}.
667
@opindex keyedit:addrevoker
668
Add a designated revoker. This takes one optional argument:
669
"sensitive". If a designated revoker is marked as sensitive, it will not
670
be exported by default (see export-options).
673
@opindex keyedit:revkey
677
@opindex keyedit:expire
678
Change the key expiration time. If a subkey is selected, the
679
expiration time of this subkey will be changed. With no selection,
680
the key expiration of the primary key is changed.
683
@opindex keyedit:passwd
684
Change the passphrase of the secret key.
687
@opindex keyedit:primary
688
Flag the current user id as the primary one, removes the primary user
689
id flag from all other user ids and sets the timestamp of all affected
690
self-signatures one second ahead. Note that setting a photo user ID
691
as primary makes it primary over other photo user IDs, and setting a
692
regular user ID as primary makes it primary over other regular user
697
Toggle selection of user id with index @code{n}.
698
Use 0 to deselect all.
702
Toggle selection of subkey with index @code{n}.
703
Use 0 to deselect all.
706
@opindex keyedit:check
707
Check all selected user ids.
710
@opindex keyedit:showphoto
711
Display the selected photographic user
715
@opindex keyedit:pref
716
List preferences from the selected user ID. This shows the actual
717
preferences, without including any implied preferences.
720
@opindex keyedit:showpref
721
More verbose preferences listing for the selected user ID. This shows
722
the preferences in effect by including the implied preferences of 3DES
723
(cipher), SHA-1 (digest), and Uncompressed (compression) if they are
724
not already included in the preference list. In addition, the
725
preferred keyserver and signature notations (if any) are shown.
727
@item setpref @code{string}
728
@opindex keyedit:setpref
729
Set the list of user ID preferences to @code{string} for all (or just
730
the selected) user IDs. Calling setpref with no arguments sets the
731
preference list to the default (either built-in or set via
732
@option{--default-preference-list}), and calling setpref with "none" as
733
the argument sets an empty preference list. Use @command{@gpgname
734
--version} to get a list of available algorithms. Note that while you
735
can change the preferences on an attribute user ID (aka "photo ID"),
736
GnuPG does not select keys via attribute user IDs so these preferences
737
will not be used by GnuPG.
740
@opindex keyedit:keyserver
741
Set a preferred keyserver for the specified user ID(s). This allows
742
other users to know where you prefer they get your key from. See
743
@option{--keyserver-options honor-keyserver-url} for more on how this
744
works. Setting a value of "none" removes an existing preferred
748
@opindex keyedit:notation
749
Set a name=value notation for the specified user ID(s). See
750
@option{--cert-notation} for more on how this works. Setting a value of
751
"none" removes all notations, setting a notation prefixed with a minus
752
sign (-) removes that notation, and setting a notation name (without the
753
=value) prefixed with a minus sign removes all notations with that name.
756
@opindex keyedit:toggle
757
Toggle between public and secret key listing.
760
@opindex keyedit:clean
761
Compact (by removing all signatures except the selfsig) any user ID
762
that is no longer usable (e.g. revoked, or expired). Then, remove any
763
signatures that are not usable by the trust calculations.
764
Specifically, this removes any signature that does not validate, any
765
signature that is superseded by a later signature, revoked signatures,
766
and signatures issued by keys that are not present on the keyring.
769
@opindex keyedit:minimize
770
Make the key as small as possible. This removes all signatures from
771
each user ID except for the most recent self-signature.
774
@opindex keyedit:cross-certify
775
Add cross-certification signatures to signing subkeys that may not
776
currently have them. Cross-certification signatures protect against a
777
subtle attack against signing subkeys. See
778
@option{--require-cross-certification}.
781
@opindex keyedit:save
782
Save all changes to the key rings and quit.
785
@opindex keyedit:quit
786
Quit the program without updating the
792
The listing shows you the key with its secondary keys and all user
793
ids. Selected keys or user ids are indicated by an asterisk. The trust
794
value is displayed with the primary key: the first is the assigned owner
795
trust and the second is the calculated trust value. Letters are used for
802
No ownertrust assigned / not yet calculated.
806
calculation has failed; probably due to an expired key.
809
Not enough information for calculation.
812
Never trust this key.
823
@c ******** End Edit-key Options **********
825
@item --sign-key @code{name}
827
Signs a public key with your secret key. This is a shortcut version of
828
the subcommand "sign" from @option{--edit}.
830
@item --lsign-key @code{name}
832
Signs a public key with your secret key but marks it as
833
non-exportable. This is a shortcut version of the subcommand "lsign"
834
from @option{--edit-key}.
840
@c *******************************************
841
@c *************** ****************
842
@c *************** OPTIONS ****************
843
@c *************** ****************
844
@c *******************************************
847
@section Option Summary
849
@command{@gpgname} comes features a bunch of options to control the exact
850
behaviour and to change the default configuration.
853
* GPG Configuration Options:: How to change the configuration.
854
* GPG Key related Options:: Key related options.
855
* GPG Input and Output:: Input and Output.
856
* OpenPGP Options:: OpenPGP protocol specific options.
857
* GPG Esoteric Options:: Doing things one usually don't want to do.
860
Long options can be put in an options file (default
861
"~/.gnupg/gpg.conf"). Short option names will not work - for example,
862
"armor" is a valid option for the options file, while "a" is not. Do not
863
write the 2 dashes, but simply the name of the option and any required
864
arguments. Lines with a hash ('#') as the first non-white-space
865
character are ignored. Commands may be put in this file too, but that is
866
not generally useful as the command will execute automatically with
867
every execution of gpg.
869
Please remember that option parsing stops as soon as a non-option is
870
encountered, you can explicitly stop parsing by using the special option
873
@c *******************************************
874
@c ******** CONFIGURATION OPTIONS **********
875
@c *******************************************
876
@node GPG Configuration Options
877
@subsection How to change the configuration
879
These options are used to change the configuration and are usually found
884
@item --default-key @var{name}
886
Use @var{name} as the default key to sign with. If this option is not
887
used, the default key is the first key found in the secret keyring.
888
Note that @option{-u} or @option{--local-user} overrides this option.
890
@item --default-recipient @var{name}
891
@opindex default-recipient
892
Use @var{name} as default recipient if option @option{--recipient} is
893
not used and don't ask if this is a valid one. @var{name} must be
896
@item --default-recipient-self
897
@opindex default-recipient-self
898
Use the default key as default recipient if option @option{--recipient} is not
899
used and don't ask if this is a valid one. The default key is the first
900
one from the secret keyring or the one set with @option{--default-key}.
902
@item --no-default-recipient
903
@opindex no-default-recipient
904
Reset @option{--default-recipient} and @option{--default-recipient-self}.
908
Give more information during processing. If used
909
twice, the input data is listed in detail.
913
Reset verbose level to 0.
917
Try to be as quiet as possible.
923
Use batch mode. Never ask, do not allow interactive commands.
924
@option{--no-batch} disables this option.
928
Make sure that the TTY (terminal) is never used for any output.
929
This option is needed in some cases because GnuPG sometimes prints
930
warnings to the TTY even if @option{--batch} is used.
934
Assume "yes" on most questions.
938
Assume "no" on most questions.
941
@item --list-options @code{parameters}
942
@opindex list-options
943
This is a space or comma delimited string that gives options used when
944
listing keys and signatures (that is, @option{--list-keys},
945
@option{--list-sigs}, @option{--list-public-keys},
946
@option{--list-secret-keys}, and the @option{--edit-key} functions).
947
Options can be prepended with a @option{no-} (after the two dashes) to
948
give the opposite meaning. The options are:
953
@opindex list-options:show-photos
954
Causes @option{--list-keys}, @option{--list-sigs},
955
@option{--list-public-keys}, and @option{--list-secret-keys} to display
956
any photo IDs attached to the key. Defaults to no. See also
957
@option{--photo-viewer}.
959
@item show-policy-urls
960
@opindex list-options:show-policy-urls
961
Show policy URLs in the @option{--list-sigs} or @option{--check-sigs}
962
listings. Defaults to no.
965
@itemx show-std-notations
966
@itemx show-user-notations
967
@opindex list-options:show-notations
968
@opindex list-options:show-std-notations
969
@opindex list-options:show-user-notations
970
Show all, IETF standard, or user-defined signature notations in the
971
@option{--list-sigs} or @option{--check-sigs} listings. Defaults to no.
973
@item show-keyserver-urls
975
Show any preferred keyserver URL in the @option{--list-sigs} or
976
@option{--check-sigs} listings. Defaults to no.
978
@item show-uid-validity
979
Display the calculated validity of user IDs during key listings.
982
@item show-unusable-uids
983
Show revoked and expired user IDs in key listings. Defaults to no.
985
@item show-unusable-subkeys
986
Show revoked and expired subkeys in key listings. Defaults to no.
989
Display the keyring name at the head of key listings to show which
990
keyring a given key resides on. Defaults to no.
992
@item show-sig-expire
993
Show signature expiration dates (if any) during @option{--list-sigs} or
994
@option{--check-sigs} listings. Defaults to no.
996
@item show-sig-subpackets
997
Include signature subpackets in the key listing. This option can take an
998
optional argument list of the subpackets to list. If no argument is
999
passed, list all subpackets. Defaults to no. This option is only
1000
meaningful when using @option{--with-colons} along with
1001
@option{--list-sigs} or @option{--check-sigs}.
1004
@item --verify-options @code{parameters}
1005
This is a space or comma delimited string that gives options used when
1006
verifying signatures. Options can be prepended with a `no-' to give
1007
the opposite meaning. The options are:
1012
Display any photo IDs present on the key that issued the signature.
1013
Defaults to no. See also @option{--photo-viewer}.
1015
@item show-policy-urls
1016
Show policy URLs in the signature being verified. Defaults to no.
1018
@item show-notations
1019
@itemx show-std-notations
1020
@itemx show-user-notations
1021
Show all, IETF standard, or user-defined signature notations in the
1022
signature being verified. Defaults to IETF standard.
1024
@item show-keyserver-urls
1025
Show any preferred keyserver URL in the signature being verified.
1028
@item show-uid-validity
1029
Display the calculated validity of the user IDs on the key that issued
1030
the signature. Defaults to no.
1032
@item show-unusable-uids
1033
Show revoked and expired user IDs during signature verification.
1036
@item show-primary-uid-only
1037
Show only the primary user ID during signature verification. That is
1038
all the AKA lines as well as photo Ids are not shown with the signature
1039
verification status.
1042
Enable PKA lookups to verify sender addresses. Note that PKA is based
1043
on DNS, and so enabling this option may disclose information on when
1044
and what signatures are verified or to whom data is encrypted. This
1045
is similar to the "web bug" described for the auto-key-retrieve
1048
@item pka-trust-increase
1049
Raise the trust in a signature to full if the signature passes PKA
1050
validation. This option is only meaningful if pka-lookups is set.
1054
@itemx --disable-dsa2
1055
Enables new-style DSA keys which (unlike the old style) may be larger
1056
than 1024 bit and use hashes other than SHA-1 and RIPEMD/160. Note
1057
that very few programs currently support these keys and signatures
1060
@item --photo-viewer @code{string}
1061
This is the command line that should be run to view a photo ID. "%i"
1062
will be expanded to a filename containing the photo. "%I" does the
1063
same, except the file will not be deleted once the viewer exits.
1064
Other flags are "%k" for the key ID, "%K" for the long key ID, "%f"
1065
for the key fingerprint, "%t" for the extension of the image type
1066
(e.g. "jpg"), "%T" for the MIME type of the image (e.g. "image/jpeg"),
1067
and "%%" for an actual percent sign. If neither %i or %I are present,
1068
then the photo will be supplied to the viewer on standard input.
1070
The default viewer is "xloadimage -fork -quiet -title 'KeyID 0x%k'
1071
stdin". Note that if your image viewer program is not secure, then
1072
executing it from GnuPG does not make it secure.
1074
@item --exec-path @code{string}
1075
Sets a list of directories to search for photo viewers and keyserver
1076
helpers. If not provided, keyserver helpers use the compiled-in
1077
default directory, and photo viewers use the $PATH environment
1079
Note, that on W32 system this value is ignored when searching for
1082
@item --keyring @code{file}
1083
Add @code{file} to the current list of keyrings. If @code{file} begins
1084
with a tilde and a slash, these are replaced by the $HOME directory. If
1085
the filename does not contain a slash, it is assumed to be in the GnuPG
1086
home directory ("~/.gnupg" if @option{--homedir} or $GNUPGHOME is not
1089
Note that this adds a keyring to the current list. If the intent is to
1090
use the specified keyring alone, use @option{--keyring} along with
1091
@option{--no-default-keyring}.
1093
@item --secret-keyring @code{file}
1094
Same as @option{--keyring} but for the secret keyrings.
1096
@item --primary-keyring @code{file}
1097
Designate @code{file} as the primary public keyring. This means that
1098
newly imported keys (via @option{--import} or keyserver
1099
@option{--recv-from}) will go to this keyring.
1101
@item --trustdb-name @code{file}
1102
Use @code{file} instead of the default trustdb. If @code{file} begins
1103
with a tilde and a slash, these are replaced by the $HOME directory. If
1104
the filename does not contain a slash, it is assumed to be in the GnuPG
1105
home directory (@file{~/.gnupg} if @option{--homedir} or $GNUPGHOME is
1109
@anchor{option --homedir}
1111
@include opt-homedir.texi
1115
@item --pcsc-driver @code{file}
1116
Use @code{file} to access the smartcard reader. The current default is
1117
`libpcsclite.so.1' for GLIBC based systems,
1118
`/System/Library/Frameworks/PCSC.framework/PCSC' for MAC OS X,
1119
`winscard.dll' for Windows and `libpcsclite.so' for other systems.
1123
@item --disable-ccid
1124
Disable the integrated support for CCID compliant readers. This
1125
allows to fall back to one of the other drivers even if the internal
1126
CCID driver can handle the reader. Note, that CCID support is only
1127
available if libusb was available at build time.
1131
@item --reader-port @code{number_or_string}
1132
This option may be used to specify the port of the card terminal. A
1133
value of 0 refers to the first serial device; add 32768 to access USB
1134
devices. The default is 32768 (first USB device). PC/SC or CCID
1135
readers might need a string here; run the program in verbose mode to get
1136
a list of available readers. The default is then the first reader
1140
@item --display-charset @code{name}
1141
Set the name of the native character set. This is used to convert
1142
some informational strings like user IDs to the proper UTF-8 encoding.
1143
Note that this has nothing to do with the character set of data to be
1144
encrypted or signed; GnuPG does not recode user-supplied data. If
1145
this option is not used, the default character set is determined from
1146
the current locale. A verbosity level of 3 shows the chosen set.
1147
Valid values for @code{name} are:
1152
This is the Latin 1 set.
1158
This is currently an alias for
1162
The usual Russian set (rfc1489).
1165
Bypass all translations and assume
1166
that the OS uses native UTF-8 encoding.
1169
@item --utf8-strings
1170
@itemx --no-utf8-strings
1171
Assume that command line arguments are given as UTF8 strings. The
1172
default (@option{--no-utf8-strings}) is to assume that arguments are
1173
encoded in the character set as specified by
1174
@option{--display-charset}. These options affect all following
1175
arguments. Both options may be used multiple times.
1178
@anchor{option --options}
1180
@item --options @code{file}
1181
Read options from @code{file} and do not try to read them from the
1182
default options file in the homedir (see @option{--homedir}). This
1183
option is ignored if used in an options file.
1186
Shortcut for @option{--options /dev/null}. This option is detected
1187
before an attempt to open an option file. Using this option will also
1188
prevent the creation of a @file{~/.gnupg} homedir.
1193
@itemx --compress-level @code{n}
1194
@itemx --bzip2-compress-level @code{n}
1195
Set compression level to @code{n} for the ZIP and ZLIB compression
1196
algorithms. The default is to use the default compression level of zlib
1197
(normally 6). @option{--bzip2-compress-level} sets the compression level
1198
for the BZIP2 compression algorithm (defaulting to 6 as well). This is a
1199
different option from @option{--compress-level} since BZIP2 uses a
1200
significant amount of memory for each additional compression level.
1201
@option{-z} sets both. A value of 0 for @code{n} disables compression.
1203
@item --bzip2-decompress-lowmem
1204
Use a different decompression method for BZIP2 compressed files. This
1205
alternate method uses a bit more than half the memory, but also runs
1206
at half the speed. This is useful under extreme low memory
1207
circumstances when the file was originally compressed at a high
1208
@option{--bzip2-compress-level}.
1211
@item --mangle-dos-filenames
1212
@itemx --no-mangle-dos-filenames
1213
@opindex mangle-dos-filenames
1214
@opindex no-mangle-dos-filenames
1215
Older version of Windows cannot handle filenames with more than one
1216
dot. @option{--mangle-dos-filenames} causes GnuPG to replace (rather
1217
than add to) the extension of an output filename to avoid this
1218
problem. This option is off by default and has no effect on non-Windows
1221
@item --ask-cert-level
1222
@itemx --no-ask-cert-level
1223
When making a key signature, prompt for a certification level. If this
1224
option is not specified, the certification level used is set via
1225
@option{--default-cert-level}. See @option{--default-cert-level} for
1226
information on the specific levels and how they are
1227
used. @option{--no-ask-cert-level} disables this option. This option
1230
@item --default-cert-level @code{n}
1231
The default to use for the check level when signing a key.
1233
0 means you make no particular claim as to how carefully you verified
1236
1 means you believe the key is owned by the person who claims to own
1237
it but you could not, or did not verify the key at all. This is
1238
useful for a "persona" verification, where you sign the key of a
1241
2 means you did casual verification of the key. For example, this
1242
could mean that you verified that the key fingerprint and checked the
1243
user ID on the key against a photo ID.
1245
3 means you did extensive verification of the key. For example, this
1246
could mean that you verified the key fingerprint with the owner of the
1247
key in person, and that you checked, by means of a hard to forge
1248
document with a photo ID (such as a passport) that the name of the key
1249
owner matches the name in the user ID on the key, and finally that you
1250
verified (by exchange of email) that the email address on the key
1251
belongs to the key owner.
1253
Note that the examples given above for levels 2 and 3 are just that:
1254
examples. In the end, it is up to you to decide just what "casual"
1255
and "extensive" mean to you.
1257
This option defaults to 0 (no particular claim).
1259
@item --min-cert-level
1260
When building the trust database, treat any signatures with a
1261
certification level below this as invalid. Defaults to 2, which
1262
disregards level 1 signatures. Note that level 0 "no particular
1263
claim" signatures are always accepted.
1265
@item --trusted-key @code{long key ID}
1266
Assume that the specified key (which must be given
1267
as a full 8 byte key ID) is as trustworthy as one of
1268
your own secret keys. This option is useful if you
1269
don't want to keep your secret keys (or one of them)
1270
online but still want to be able to check the validity of a given
1271
recipient's or signator's key.
1273
@item --trust-model @code{pgp|classic|direct|always|auto}
1274
Set what trust model GnuPG should follow. The models are:
1279
This is the Web of Trust combined with trust signatures as used in PGP
1280
5.x and later. This is the default trust model when creating a new
1284
This is the standard Web of Trust as used in PGP 2.x and earlier.
1287
Key validity is set directly by the user and not calculated via the
1291
Skip key validation and assume that used keys are always fully
1292
trusted. You generally won't use this unless you are using some
1293
external validation scheme. This option also suppresses the
1294
"[uncertain]" tag printed with signature checks when there is no
1295
evidence that the user ID is bound to the key.
1298
Select the trust model depending on whatever the internal trust
1299
database says. This is the default model if such a database already
1303
@item --auto-key-locate @code{parameters}
1304
@itemx --no-auto-key-locate
1305
GnuPG can automatically locate and retrieve keys as needed using this
1306
option. This happens when encrypting to an email address (in the
1307
"user@@example.com" form), and there are no user@@example.com keys on
1308
the local keyring. This option takes any number of the following
1309
arguments, in the order they are to be tried:
1314
locate a key using DNS CERT, as specified in rfc4398.
1317
locate a key using DNS PKA.
1320
locate a key using the PGP Universal method of checking
1321
"ldap://keys.(thedomain)".
1324
locate a key using whatever keyserver is defined using the
1325
@option{--keyserver} option.
1327
@item (keyserver URL)
1328
In addition, a keyserver URL as used in the @option{--keyserver} option may be
1329
used here to query that particular keyserver.
1332
@item --keyid-format @code{short|0xshort|long|0xlong}
1333
Select how to display key IDs. "short" is the traditional 8-character
1334
key ID. "long" is the more accurate (but less convenient)
1335
16-character key ID. Add an "0x" to either to include an "0x" at the
1336
beginning of the key ID, as in 0x99242560.
1338
@item --keyserver @code{name}
1339
Use @code{name} as your keyserver. This is the server that
1340
@option{--recv-keys}, @option{--send-keys}, and @option{--search-keys}
1341
will communicate with to receive keys from, send keys to, and search for
1342
keys on. The format of the @code{name} is a URI:
1343
`scheme:[//]keyservername[:port]' The scheme is the type of keyserver:
1344
"hkp" for the HTTP (or compatible) keyservers, "ldap" for the LDAP
1345
keyservers, or "mailto" for the Graff email keyserver. Note that your
1346
particular installation of GnuPG may have other keyserver types
1347
available as well. Keyserver schemes are case-insensitive. After the
1348
keyserver name, optional keyserver configuration options may be
1349
provided. These are the same as the global @option{--keyserver-options}
1350
from below, but apply only to this particular keyserver.
1352
Most keyservers synchronize with each other, so there is generally no
1353
need to send keys to more than one server. The keyserver
1354
@code{hkp://subkeys.pgp.net} uses round robin DNS to give a different
1355
keyserver each time you use it.
1357
@item --keyserver-options @code{name=value1 }
1358
This is a space or comma delimited string that gives options for the
1359
keyserver. Options can be prepended with a `no-' to give the opposite
1360
meaning. Valid import-options or export-options may be used here as well
1361
to apply to importing (@option{--recv-key}) or exporting
1362
(@option{--send-key}) a key from a keyserver. While not all options are
1363
available for all keyserver types, some common options are:
1367
@item include-revoked
1368
When searching for a key with @option{--search-keys}, include keys that
1369
are marked on the keyserver as revoked. Note that not all keyservers
1370
differentiate between revoked and unrevoked keys, and for such
1371
keyservers this option is meaningless. Note also that most keyservers do
1372
not have cryptographic verification of key revocations, and so turning
1373
this option off may result in skipping keys that are incorrectly marked
1376
@item include-disabled
1377
When searching for a key with @option{--search-keys}, include keys that
1378
are marked on the keyserver as disabled. Note that this option is not
1379
used with HKP keyservers.
1381
@item auto-key-retrieve
1382
This option enables the automatic retrieving of keys from a keyserver
1383
when verifying signatures made by keys that are not on the local
1386
Note that this option makes a "web bug" like behavior possible.
1387
Keyserver operators can see which keys you request, so by sending you
1388
a message signed by a brand new key (which you naturally will not have
1389
on your local keyring), the operator can tell both your IP address and
1390
the time when you verified the signature.
1392
@item honor-keyserver-url
1393
When using @option{--refresh-keys}, if the key in question has a preferred
1394
keyserver URL, then use that preferred keyserver to refresh the key
1395
from. In addition, if auto-key-retrieve is set, and the signature
1396
being verified has a preferred keyserver URL, then use that preferred
1397
keyserver to fetch the key from. Defaults to yes.
1399
@item honor-pka-record
1400
If auto-key-retrieve is set, and the signature being verified has a
1401
PKA record, then use the PKA information to fetch the key. Defaults
1404
@item include-subkeys
1405
When receiving a key, include subkeys as potential targets. Note that
1406
this option is not used with HKP keyservers, as they do not support
1407
retrieving keys by subkey id.
1409
@item use-temp-files
1410
On most Unix-like platforms, GnuPG communicates with the keyserver
1411
helper program via pipes, which is the most efficient method. This
1412
option forces GnuPG to use temporary files to communicate. On some
1413
platforms (such as Win32 and RISC OS), this option is always enabled.
1415
@item keep-temp-files
1416
If using `use-temp-files', do not delete the temp files after using
1417
them. This option is useful to learn the keyserver communication
1418
protocol by reading the temporary files.
1421
Tell the keyserver helper program to be more verbose. This option can
1422
be repeated multiple times to increase the verbosity level.
1425
Tell the keyserver helper program how long (in seconds) to try and
1426
perform a keyserver action before giving up. Note that performing
1427
multiple actions at the same time uses this timeout value per action.
1428
For example, when retrieving multiple keys via @option{--recv-keys}, the
1429
timeout applies separately to each key retrieval, and not to the
1430
@option{--recv-keys} command as a whole. Defaults to 30 seconds.
1432
@item http-proxy=@code{value}
1433
Set the proxy to use for HTTP and HKP keyservers. This overrides the
1434
"http_proxy" environment variable, if any.
1437
When retrieving a key via DNS CERT, only accept keys up to this size.
1438
Defaults to 16384 bytes.
1441
@item --completes-needed @code{n}
1442
Number of completely trusted users to introduce a new
1443
key signer (defaults to 1).
1445
@item --marginals-needed @code{n}
1446
Number of marginally trusted users to introduce a new
1447
key signer (defaults to 3)
1449
@item --max-cert-depth @code{n}
1450
Maximum depth of a certification chain (default is 5).
1452
@item --simple-sk-checksum
1453
Secret keys are integrity protected by using a SHA-1 checksum. This
1454
method is part of the upcoming enhanced OpenPGP specification but
1455
GnuPG already uses it as a countermeasure against certain attacks.
1456
Old applications don't understand this new format, so this option may
1457
be used to switch back to the old behaviour. Using this option bears
1458
a security risk. Note that using this option only takes effect when
1459
the secret key is encrypted - the simplest way to make this happen is
1460
to change the passphrase on the key (even changing it to the same
1461
value is acceptable).
1463
@item --no-sig-cache
1464
Do not cache the verification status of key signatures.
1465
Caching gives a much better performance in key listings. However, if
1466
you suspect that your public keyring is not save against write
1467
modifications, you can use this option to disable the caching. It
1468
probably does not make sense to disable it because all kind of damage
1469
can be done if someone else has write access to your public keyring.
1471
@item --no-sig-create-check
1472
GnuPG normally verifies each signature right after creation to protect
1473
against bugs and hardware malfunctions which could leak out bits from
1474
the secret key. This extra verification needs some time (about 115%
1475
for DSA keys), and so this option can be used to disable it.
1476
However, due to the fact that the signature creation needs manual
1477
interaction, this performance penalty does not matter in most settings.
1479
@item --auto-check-trustdb
1480
@itemx --no-auto-check-trustdb
1481
If GnuPG feels that its information about the Web of Trust has to be
1482
updated, it automatically runs the @option{--check-trustdb} command
1483
internally. This may be a time consuming
1484
process. @option{--no-auto-check-trustdb} disables this option.
1487
@itemx --no-use-agent
1489
This is dummy option. @command{@gpgname} always requires the agent.
1492
Try to use the GnuPG-Agent. With this option, GnuPG first tries to
1493
connect to the agent before it asks for a
1494
passphrase. @option{--no-use-agent} disables this option.
1497
@item --gpg-agent-info
1499
This is dummy option. It has no effect when used with @command{gpg2}.
1502
Override the value of the environment variable
1503
@samp{GPG_AGENT_INFO}. This is only used when @option{--use-agent} has
1504
been given. Given that this option is not anymore used by
1505
@command{gpg2}, it should be avoided if possible.
1509
Lock the databases the first time a lock is requested
1510
and do not release the lock until the process
1513
@item --lock-multiple
1514
Release the locks every time a lock is no longer
1515
needed. Use this to override a previous @option{--lock-once}
1519
Disable locking entirely. This option should be used only in very
1520
special environments, where it can be assured that only one process
1521
is accessing those files. A bootable floppy with a stand-alone
1522
encryption system will probably use this. Improper usage of this
1523
option may lead to data and key corruption.
1525
@item --exit-on-status-write-error
1526
This option will cause write errors on the status FD to immediately
1527
terminate the process. That should in fact be the default but it never
1528
worked this way and thus we need an option to enable this, so that the
1529
change won't break applications which close their end of a status fd
1530
connected pipe too early. Using this option along with
1531
@option{--enable-progress-filter} may be used to cleanly cancel long
1532
running gpg operations.
1534
@item --limit-card-insert-tries @code{n}
1535
With @code{n} greater than 0 the number of prompts asking to insert a
1536
smartcard gets limited to N-1. Thus with a value of 1 gpg won't at
1537
all ask to insert a card if none has been inserted at startup. This
1538
option is useful in the configuration file in case an application does
1539
not know about the smartcard support and waits ad infinitum for an
1542
@item --no-random-seed-file
1543
GnuPG uses a file to store its internal random pool over invocations.
1544
This makes random generation faster; however sometimes write operations
1545
are not desired. This option can be used to achieve that with the cost of
1546
slower random generation.
1549
Suppress the initial copyright message.
1551
@item --no-secmem-warning
1552
Suppress the warning about "using insecure memory".
1554
@item --no-permission-warning
1555
Suppress the warning about unsafe file and home directory (@option{--homedir})
1556
permissions. Note that the permission checks that GnuPG performs are
1557
not intended to be authoritative, but rather they simply warn about
1558
certain common permission problems. Do not assume that the lack of a
1559
warning means that your system is secure.
1561
Note that the warning for unsafe @option{--homedir} permissions cannot be
1562
suppressed in the gpg.conf file, as this would allow an attacker to
1563
place an unsafe gpg.conf file in place, and use this file to suppress
1564
warnings about itself. The @option{--homedir} permissions warning may only be
1565
suppressed on the command line.
1567
@item --no-mdc-warning
1568
Suppress the warning about missing MDC integrity protection.
1570
@item --require-secmem
1571
@itemx --no-require-secmem
1572
Refuse to run if GnuPG cannot get secure memory. Defaults to no
1573
(i.e. run, but give a warning).
1576
@item --require-cross-certification
1577
@itemx --no-require-cross-certification
1578
When verifying a signature made from a subkey, ensure that the cross
1579
certification "back signature" on the subkey is present and valid. This
1580
protects against a subtle attack against subkeys that can sign.
1581
Defaults to @option{--require-cross-certification} for
1586
Allow the user to do certain nonsensical or "silly" things like
1587
signing an expired or revoked key, or certain potentially incompatible
1588
things like generating unusual key types. This also disables certain
1589
warning messages about potentially incompatible actions. As the name
1590
implies, this option is for experts only. If you don't fully
1591
understand the implications of what it allows you to do, leave this
1592
off. @option{--no-expert} disables this option.
1600
@c *******************************************
1601
@c ******** KEY RELATED OPTIONS ************
1602
@c *******************************************
1603
@node GPG Key related Options
1604
@subsection Key related options
1608
@item --recipient @var{name}
1611
Encrypt for user id @var{name}. If this option or
1612
@option{--hidden-recipient} is not specified, GnuPG asks for the user-id
1613
unless @option{--default-recipient} is given.
1615
@item --hidden-recipient @var{name}
1617
@opindex hidden-recipient
1618
Encrypt for user ID @var{name}, but hide the key ID of this user's
1619
key. This option helps to hide the receiver of the message and is a
1620
limited countermeasure against traffic analysis. If this option or
1621
@option{--recipient} is not specified, GnuPG asks for the user ID unless
1622
@option{--default-recipient} is given.
1624
@item --encrypt-to @code{name}
1625
Same as @option{--recipient} but this one is intended for use in the
1626
options file and may be used with your own user-id as an
1627
"encrypt-to-self". These keys are only used when there are other
1628
recipients given either by use of @option{--recipient} or by the asked
1629
user id. No trust checking is performed for these user ids and even
1630
disabled keys can be used.
1632
@item --hidden-encrypt-to @code{name}
1633
Same as @option{--hidden-recipient} but this one is intended for use in the
1634
options file and may be used with your own user-id as a hidden
1635
"encrypt-to-self". These keys are only used when there are other
1636
recipients given either by use of @option{--recipient} or by the asked user id.
1637
No trust checking is performed for these user ids and even disabled
1640
@item --no-encrypt-to
1641
Disable the use of all @option{--encrypt-to} and
1642
@option{--hidden-encrypt-to} keys.
1644
@item --group @code{name=value1 }
1645
Sets up a named group, which is similar to aliases in email programs.
1646
Any time the group name is a recipient (@option{-r} or
1647
@option{--recipient}), it will be expanded to the values
1648
specified. Multiple groups with the same name are automatically merged
1649
into a single group.
1651
The values are @code{key IDs} or fingerprints, but any key description
1652
is accepted. Note that a value with spaces in it will be treated as
1653
two different values. Note also there is only one level of expansion
1654
--- you cannot make an group that points to another group. When used
1655
from the command line, it may be necessary to quote the argument to
1656
this option to prevent the shell from treating it as multiple
1659
@item --ungroup @code{name}
1660
Remove a given entry from the @option{--group} list.
1663
Remove all entries from the @option{--group} list.
1665
@item --local-user @var{name}
1668
Use @var{name} as the key to sign with. Note that this option overrides
1669
@option{--default-key}.
1671
@item --try-all-secrets
1672
Don't look at the key ID as stored in the message but try all secret
1673
keys in turn to find the right decryption key. This option forces the
1674
behaviour as used by anonymous recipients (created by using
1675
@option{--throw-keyids}) and might come handy in case where an encrypted
1676
message contains a bogus key ID.
1684
@c *******************************************
1685
@c ******** INPUT AND OUTPUT ***************
1686
@c *******************************************
1687
@node GPG Input and Output
1688
@subsection Input and Output
1695
Create ASCII armored output. The default is to create the binary
1699
Assume the input data is not in ASCII armored format.
1701
@item --output @var{file}
1702
@itemx -o @var{file}
1704
Write output to @var{file}.
1706
@item --max-output @code{n}
1708
This option sets a limit on the number of bytes that will be generated
1709
when processing a file. Since OpenPGP supports various levels of
1710
compression, it is possible that the plaintext of a given message may be
1711
significantly larger than the original OpenPGP message. While GnuPG
1712
works properly with such messages, there is often a desire to set a
1713
maximum file size that will be generated before processing is forced to
1714
stop by the OS limits. Defaults to 0, which means "no limit".
1716
@item --import-options @code{parameters}
1717
This is a space or comma delimited string that gives options for
1718
importing keys. Options can be prepended with a `no-' to give the
1719
opposite meaning. The options are:
1723
@item import-local-sigs
1724
Allow importing key signatures marked as "local". This is not
1725
generally useful unless a shared keyring scheme is being used.
1728
@item repair-pks-subkey-bug
1729
During import, attempt to repair the damage caused by the PKS keyserver
1730
bug (pre version 0.9.6) that mangles keys with multiple subkeys. Note
1731
that this cannot completely repair the damaged key as some crucial data
1732
is removed by the keyserver, but it does at least give you back one
1733
subkey. Defaults to no for regular @option{--import} and to yes for
1734
keyserver @option{--recv-keys}.
1737
During import, allow key updates to existing keys, but do not allow
1738
any new keys to be imported. Defaults to no.
1741
After import, compact (remove all signatures except the
1742
self-signature) any user IDs from the new key that are not usable.
1743
Then, remove any signatures from the new key that are not usable.
1744
This includes signatures that were issued by keys that are not present
1745
on the keyring. This option is the same as running the @option{--edit-key}
1746
command "clean" after import. Defaults to no.
1748
@item import-minimal
1749
Import the smallest key possible. This removes all signatures except
1750
the most recent self-signature on each user ID. This option is the
1751
same as running the @option{--edit-key} command "minimize" after import.
1755
@item --export-options @code{parameters}
1756
This is a space or comma delimited string that gives options for
1757
exporting keys. Options can be prepended with a `no-' to give the
1758
opposite meaning. The options are:
1762
@item export-local-sigs
1763
Allow exporting key signatures marked as "local". This is not
1764
generally useful unless a shared keyring scheme is being used.
1767
@item export-attributes
1768
Include attribute user IDs (photo IDs) while exporting. This is
1769
useful to export keys if they are going to be used by an OpenPGP
1770
program that does not accept attribute user IDs. Defaults to yes.
1772
@item export-sensitive-revkeys
1773
Include designated revoker information that was marked as
1774
"sensitive". Defaults to no.
1776
@item export-reset-subkey-passwd
1777
When using the @option{--export-secret-subkeys} command, this option resets
1778
the passphrases for all exported subkeys to empty. This is useful
1779
when the exported subkey is to be used on an unattended machine where
1780
a passphrase doesn't necessarily make sense. Defaults to no.
1783
Compact (remove all signatures from) user IDs on the key being
1784
exported if the user IDs are not usable. Also, do not export any
1785
signatures that are not usable. This includes signatures that were
1786
issued by keys that are not present on the keyring. This option is
1787
the same as running the @option{--edit-key} command "clean" before export
1788
except that the local copy of the key is not modified. Defaults to
1791
@item export-minimal
1792
Export the smallest key possible. This removes all signatures except the
1793
most recent self-signature on each user ID. This option is the same as
1794
running the @option{--edit-key} command "minimize" before export except
1795
that the local copy of the key is not modified. Defaults to no.
1799
@opindex with-colons
1800
Print key listings delimited by colons. Note that the output will be
1801
encoded in UTF-8 regardless of any @option{--display-charset} setting. This
1802
format is useful when GnuPG is called from scripts and other programs
1803
as it is easily machine parsed. The details of this format are
1804
documented in the file @file{doc/DETAILS}, which is included in the GnuPG
1805
source distribution.
1807
@item --fixed-list-mode
1808
@opindex fixed-list-mode
1809
Do not merge primary user ID and primary key in @option{--with-colon}
1810
listing mode and print all timestamps as seconds since 1970-01-01.
1812
@item --with-fingerprint
1813
@opindex with-fingerprint
1814
Same as the command @option{--fingerprint} but changes only the format
1815
of the output and may be used together with another command.
1820
@c *******************************************
1821
@c ******** OPENPGP OPTIONS ****************
1822
@c *******************************************
1823
@node OpenPGP Options
1824
@subsection OpenPGP protocol specific options.
1828
@item -t, --textmode
1829
@itemx --no-textmode
1830
Treat input files as text and store them in the OpenPGP canonical text
1831
form with standard "CRLF" line endings. This also sets the necessary
1832
flags to inform the recipient that the encrypted or signed data is text
1833
and may need its line endings converted back to whatever the local
1834
system uses. This option is useful when communicating between two
1835
platforms that have different line ending conventions (UNIX-like to Mac,
1836
Mac to Windows, etc). @option{--no-textmode} disables this option, and
1840
If @option{-t} (but not @option{--textmode}) is used together with
1841
armoring and signing, this enables clearsigned messages. This kludge is
1842
needed for command-line compatibility with command-line versions of PGP;
1843
normally you would use @option{--sign} or @option{--clearsign} to select
1844
the type of the signature.
1847
@item --force-v3-sigs
1848
@itemx --no-force-v3-sigs
1849
OpenPGP states that an implementation should generate v4 signatures
1850
but PGP versions 5 through 7 only recognize v4 signatures on key
1851
material. This option forces v3 signatures for signatures on data.
1852
Note that this option implies @option{--ask-sig-expire},
1853
@option{--sig-policy-url}, @option{--sig-notation}, and
1854
@option{--sig-keyserver-url}, as these features cannot be used with v3
1855
signatures. @option{--no-force-v3-sigs} disables this option.
1857
@item --force-v4-certs
1858
@itemx --no-force-v4-certs
1859
Always use v4 key signatures even on v3 keys. This option also
1860
changes the default hash algorithm for v3 RSA keys from MD5 to SHA-1.
1861
@option{--no-force-v4-certs} disables this option.
1864
Force the use of encryption with a modification detection code. This
1865
is always used with the newer ciphers (those with a blocksize greater
1866
than 64 bits), or if all of the recipient keys indicate MDC support in
1867
their feature flags.
1870
Disable the use of the modification detection code. Note that by
1871
using this option, the encrypted message becomes vulnerable to a
1872
message modification attack.
1874
@item --personal-cipher-preferences @code{string}
1875
Set the list of personal cipher preferences to @code{string}. Use
1876
@command{@gpgname --version} to get a list of available algorithms,
1877
and use @code{none} to set no preference at all. This allows the user
1878
to factor in their own preferred algorithms when algorithms are chosen
1879
via recipient key preferences. The most highly ranked cipher in this
1880
list is also used for the @option{--symmetric} encryption command.
1882
@item --personal-digest-preferences @code{string}
1883
Set the list of personal digest preferences to @code{string}. Use
1884
@command{@gpgname --version} to get a list of available algorithms,
1885
and use @code{none} to set no preference at all. This allows the user
1886
to factor in their own preferred algorithms when algorithms are chosen
1887
via recipient key preferences. The most highly ranked digest
1888
algorithm in this list is algo used when signing without encryption
1889
(e.g. @option{--clearsign} or @option{--sign}). The default value is
1892
@item --personal-compress-preferences @code{string}
1893
Set the list of personal compression preferences to @code{string}.
1894
Use @command{@gpgname --version} to get a list of available
1895
algorithms, and use @code{none} to set no preference at all. This
1896
allows the user to factor in their own preferred algorithms when
1897
algorithms are chosen via recipient key preferences. The most highly
1898
ranked compression algorithm in this list is algo used when there are
1899
no recipient keys to consider (e.g. @option{--symmetric}).
1901
@item --s2k-cipher-algo @code{name}
1902
Use @code{name} as the cipher algorithm used to protect secret keys.
1903
The default cipher is CAST5. This cipher is also used for
1904
conventional encryption if @option{--personal-cipher-preferences} and
1905
@option{--cipher-algo} is not given.
1907
@item --s2k-digest-algo @code{name}
1908
Use @code{name} as the digest algorithm used to mangle the passphrases.
1909
The default algorithm is SHA-1.
1911
@item --s2k-mode @code{n}
1912
Selects how passphrases are mangled. If @code{n} is 0 a plain
1913
passphrase (which is not recommended) will be used, a 1 adds a salt to
1914
the passphrase and a 3 (the default) iterates the whole process a
1915
number of times (see --s2k-count). Unless @option{--rfc1991} is used,
1916
this mode is also used for conventional encryption.
1918
@item --s2k-count @code{n}
1919
Specify how many times the passphrase mangling is repeated. This
1920
value may range between 1024 and 65011712 inclusive, and the default
1921
is 65536. Note that not all values in the 1024-65011712 range are
1922
legal and if an illegal value is selected, GnuPG will round up to the
1923
nearest legal value. This option is only meaningful if
1924
@option{--s2k-mode} is 3.
1929
@c ***************************
1930
@c ******* Compliance ********
1931
@c ***************************
1932
@subsection Compliance options
1934
These options control what GnuPG is compliant to. Only one of these
1935
options may be active at a time. Note that the default setting of
1936
this is nearly always the correct one. See the INTEROPERABILITY WITH
1937
OTHER OPENPGP PROGRAMS section below before using one of these
1944
Use standard GnuPG behavior. This is essentially OpenPGP behavior
1945
(see @option{--openpgp}), but with some additional workarounds for common
1946
compatibility problems in different versions of PGP. This is the
1947
default option, so it is not generally needed, but it may be useful to
1948
override a different compliance option in the gpg.conf file.
1952
Reset all packet, cipher and digest options to strict OpenPGP
1953
behavior. Use this option to reset all previous options like
1954
@option{--s2k-*}, @option{--cipher-algo}, @option{--digest-algo} and
1955
@option{--compress-algo} to OpenPGP compliant values. All PGP
1956
workarounds are disabled.
1960
Reset all packet, cipher and digest options to strict RFC-4880
1961
behavior. Note that this is currently the same thing as
1966
Reset all packet, cipher and digest options to strict RFC-2440
1971
Try to be more RFC-1991 (PGP 2.x) compliant.
1975
Set up all options to be as PGP 2.x compliant as possible, and warn if
1976
an action is taken (e.g. encrypting to a non-RSA key) that will create
1977
a message that PGP 2.x will not be able to handle. Note that `PGP
1978
2.x' here means `MIT PGP 2.6.2'. There are other versions of PGP 2.x
1979
available, but the MIT release is a good common baseline.
1981
This option implies @option{--rfc1991 --disable-mdc
1982
--no-force-v4-certs --no-sk-comment --escape-from-lines
1983
--force-v3-sigs --cipher-algo IDEA --digest-algo MD5 --compress-algo
1984
ZIP}. It also disables @option{--textmode} when encrypting.
1988
Set up all options to be as PGP 6 compliant as possible. This
1989
restricts you to the ciphers IDEA (if the IDEA plugin is installed),
1990
3DES, and CAST5, the hashes MD5, SHA1 and RIPEMD160, and the
1991
compression algorithms none and ZIP. This also disables
1992
--throw-keyids, and making signatures with signing subkeys as PGP 6
1993
does not understand signatures made by signing subkeys.
1995
This option implies @option{--disable-mdc --no-sk-comment
1996
--escape-from-lines --force-v3-sigs}.
2000
Set up all options to be as PGP 7 compliant as possible. This is
2001
identical to @option{--pgp6} except that MDCs are not disabled, and the
2002
list of allowable ciphers is expanded to add AES128, AES192, AES256, and
2007
Set up all options to be as PGP 8 compliant as possible. PGP 8 is a lot
2008
closer to the OpenPGP standard than previous versions of PGP, so all
2009
this does is disable @option{--throw-keyids} and set
2010
@option{--escape-from-lines}. All algorithms are allowed except for the
2011
SHA224, SHA384, and SHA512 digests.
2016
@c *******************************************
2017
@c ******** ESOTERIC OPTIONS ***************
2018
@c *******************************************
2019
@node GPG Esoteric Options
2020
@subsection Doing things one usually doesn't want to do.
2027
Don't make any changes (this is not completely implemented).
2030
Changes the behaviour of some commands. This is like @option{--dry-run} but
2031
different in some cases. The semantic of this command may be extended in
2032
the future. Currently it only skips the actual decryption pass and
2033
therefore enables a fast listing of the encryption keys.
2036
@itemx --interactive
2037
@opindex interactive
2038
Prompt before overwriting any files.
2040
@item --debug @var{flags}
2042
Set debugging flags. All flags are or-ed and @var{flags} may
2043
be given in C syntax (e.g. 0x0042).
2046
Set all useful debugging flags.
2049
@item --debug-ccid-driver
2050
Enable debug output from the included CCID driver for smartcards.
2051
Note that this option is only available on some system.
2054
@item --enable-progress-filter
2055
Enable certain PROGRESS status outputs. This option allows frontends
2056
to display a progress indicator while gpg is processing larger files.
2057
There is a slight performance overhead using it.
2059
@item --status-fd @code{n}
2060
Write special status strings to the file descriptor @code{n}.
2061
See the file DETAILS in the documentation for a listing of them.
2063
@item --status-file @code{file}
2064
Same as @option{--status-fd}, except the status data is written to file
2067
@item --logger-fd @code{n}
2068
Write log output to file descriptor @code{n} and not to stderr.
2070
@item --log-file @code{file}
2071
@itemx --logger-file @code{file}
2072
Same as @option{--logger-fd}, except the logger data is written to file
2073
@code{file}. Note that @option{--log-file} is only implemented for
2076
@item --attribute-fd @code{n}
2077
Write attribute subpackets to the file descriptor @code{n}. This is most
2078
useful for use with @option{--status-fd}, since the status messages are
2079
needed to separate out the various subpackets from the stream delivered
2080
to the file descriptor.
2082
@item --attribute-file @code{file}
2083
Same as @option{--attribute-fd}, except the attribute data is written to
2086
@item --comment @code{string}
2087
@itemx --no-comments
2088
Use @code{string} as a comment string in clear text signatures and ASCII
2089
armored messages or keys (see @option{--armor}). The default behavior is
2090
not to use a comment string. @option{--comment} may be repeated multiple
2091
times to get multiple comment strings. @option{--no-comments} removes
2092
all comments. It is a good idea to keep the length of a single comment
2093
below 60 characters to avoid problems with mail programs wrapping such
2094
lines. Note that comment lines, like all other header lines, are not
2095
protected by the signature.
2097
@item --emit-version
2098
@itemx --no-emit-version
2099
Force inclusion of the version string in ASCII armored output.
2100
@option{--no-emit-version} disables this option.
2102
@item --sig-notation @code{name=value}
2103
@itemx --cert-notation @code{name=value}
2104
@itemx -N, --set-notation @code{name=value}
2105
Put the name value pair into the signature as notation data.
2106
@code{name} must consist only of printable characters or spaces, and
2107
must contain a '@@' character in the form keyname@@domain.example.com
2108
(substituting the appropriate keyname and domain name, of course). This
2109
is to help prevent pollution of the IETF reserved notation
2110
namespace. The @option{--expert} flag overrides the '@@'
2111
check. @code{value} may be any printable string; it will be encoded in
2112
UTF8, so you should check that your @option{--display-charset} is set
2113
correctly. If you prefix @code{name} with an exclamation mark (!), the
2114
notation data will be flagged as critical
2115
(rfc2440:5.2.3.15). @option{--sig-notation} sets a notation for data
2116
signatures. @option{--cert-notation} sets a notation for key signatures
2117
(certifications). @option{--set-notation} sets both.
2119
There are special codes that may be used in notation names. "%k" will
2120
be expanded into the key ID of the key being signed, "%K" into the
2121
long key ID of the key being signed, "%f" into the fingerprint of the
2122
key being signed, "%s" into the key ID of the key making the
2123
signature, "%S" into the long key ID of the key making the signature,
2124
"%g" into the fingerprint of the key making the signature (which might
2125
be a subkey), "%p" into the fingerprint of the primary key of the key
2126
making the signature, "%c" into the signature count from the OpenPGP
2127
smartcard, and "%%" results in a single "%". %k, %K, and %f are only
2128
meaningful when making a key signature (certification), and %c is only
2129
meaningful when using the OpenPGP smartcard.
2131
@item --sig-policy-url @code{string}
2132
@itemx --cert-policy-url @code{string}
2133
@itemx --set-policy-url @code{string}
2134
Use @code{string} as a Policy URL for signatures (rfc2440:5.2.3.19). If
2135
you prefix it with an exclamation mark (!), the policy URL packet will
2136
be flagged as critical. @option{--sig-policy-url} sets a policy url for
2137
data signatures. @option{--cert-policy-url} sets a policy url for key
2138
signatures (certifications). @option{--set-policy-url} sets both.
2140
The same %-expandos used for notation data are available here as well.
2142
@item --sig-keyserver-url @code{string}
2143
Use @code{string} as a preferred keyserver URL for data signatures. If
2144
you prefix it with an exclamation mark (!), the keyserver URL packet
2145
will be flagged as critical.
2147
The same %-expandos used for notation data are available here as well.
2149
@item --set-filename @code{string}
2150
Use @code{string} as the filename which is stored inside messages.
2151
This overrides the default, which is to use the actual filename of the
2152
file being encrypted.
2154
@item --for-your-eyes-only
2155
@itemx --no-for-your-eyes-only
2156
Set the `for your eyes only' flag in the message. This causes GnuPG to
2157
refuse to save the file unless the @option{--output} option is given,
2158
and PGP to use a "secure viewer" with a claimed Tempest-resistant font
2159
to display the message. This option overrides @option{--set-filename}.
2160
@option{--no-for-your-eyes-only} disables this option.
2162
@item --use-embedded-filename
2163
@itemx --no-use-embedded-filename
2164
Try to create a file with a name as embedded in the data. This can be
2165
a dangerous option as it allows to overwrite files. Defaults to no.
2167
@item --cipher-algo @code{name}
2168
Use @code{name} as cipher algorithm. Running the program with the
2169
command @option{--version} yields a list of supported algorithms. If
2170
this is not used the cipher algorithm is selected from the preferences
2171
stored with the key. In general, you do not want to use this option as
2172
it allows you to violate the OpenPGP standard.
2173
@option{--personal-cipher-preferences} is the safe way to accomplish the
2176
@item --digest-algo @code{name}
2177
Use @code{name} as the message digest algorithm. Running the program
2178
with the command @option{--version} yields a list of supported algorithms. In
2179
general, you do not want to use this option as it allows you to
2180
violate the OpenPGP standard. @option{--personal-digest-preferences} is the
2181
safe way to accomplish the same thing.
2183
@item --compress-algo @code{name}
2184
Use compression algorithm @code{name}. "zlib" is RFC-1950 ZLIB
2185
compression. "zip" is RFC-1951 ZIP compression which is used by PGP.
2186
"bzip2" is a more modern compression scheme that can compress some
2187
things better than zip or zlib, but at the cost of more memory used
2188
during compression and decompression. "uncompressed" or "none"
2189
disables compression. If this option is not used, the default
2190
behavior is to examine the recipient key preferences to see which
2191
algorithms the recipient supports. If all else fails, ZIP is used for
2192
maximum compatibility.
2194
ZLIB may give better compression results than ZIP, as the compression
2195
window size is not limited to 8k. BZIP2 may give even better
2196
compression results than that, but will use a significantly larger
2197
amount of memory while compressing and decompressing. This may be
2198
significant in low memory situations. Note, however, that PGP (all
2199
versions) only supports ZIP compression. Using any algorithm other
2200
than ZIP or "none" will make the message unreadable with PGP. In
2201
general, you do not want to use this option as it allows you to
2202
violate the OpenPGP standard. @option{--personal-compress-preferences} is the
2203
safe way to accomplish the same thing.
2205
@item --cert-digest-algo @code{name}
2206
Use @code{name} as the message digest algorithm used when signing a
2207
key. Running the program with the command @option{--version} yields a
2208
list of supported algorithms. Be aware that if you choose an algorithm
2209
that GnuPG supports but other OpenPGP implementations do not, then some
2210
users will not be able to use the key signatures you make, or quite
2211
possibly your entire key.
2213
@item --disable-cipher-algo @code{name}
2214
Never allow the use of @code{name} as cipher algorithm.
2215
The given name will not be checked so that a later loaded algorithm
2216
will still get disabled.
2218
@item --disable-pubkey-algo @code{name}
2219
Never allow the use of @code{name} as public key algorithm.
2220
The given name will not be checked so that a later loaded algorithm
2221
will still get disabled.
2223
@item --throw-keyids
2224
@itemx --no-throw-keyids
2225
Do not put the recipient key IDs into encrypted messages. This helps
2226
to hide the receivers of the message and is a limited countermeasure
2227
against traffic analysis. On the receiving side, it may slow down the
2228
decryption process because all available secret keys must be tried.
2229
@option{--no-throw-keyids} disables this option. This option is essentially
2230
the same as using @option{--hidden-recipient} for all recipients.
2232
@item --not-dash-escaped
2233
This option changes the behavior of cleartext signatures
2234
so that they can be used for patch files. You should not
2235
send such an armored file via email because all spaces
2236
and line endings are hashed too. You can not use this
2237
option for data which has 5 dashes at the beginning of a
2238
line, patch files don't have this. A special armor header
2239
line tells GnuPG about this cleartext signature option.
2241
@item --escape-from-lines
2242
@itemx --no-escape-from-lines
2243
Because some mailers change lines starting with "From " to ">From " it
2244
is good to handle such lines in a special way when creating cleartext
2245
signatures to prevent the mail system from breaking the signature. Note
2246
that all other PGP versions do it this way too. Enabled by
2247
default. @option{--no-escape-from-lines} disables this option.
2249
@item --passphrase-repeat @code{n}
2250
Specify how many times @command{@gpgname} will request a new
2251
passphrase be repeated. This is useful for helping memorize a
2252
passphrase. Defaults to 1 repetition.
2254
@item --passphrase-fd @code{n}
2255
Read the passphrase from file descriptor @code{n}. Only the first line
2256
will be read from file descriptor @code{n}. If you use 0 for @code{n},
2257
the passphrase will be read from stdin. This can only be used if only
2258
one passphrase is supplied.
2260
Note that this passphrase is only used if the option @option{--batch}
2261
has also been given. This is different from @command{gpg}.
2264
@item --passphrase-file @code{file}
2265
Read the passphrase from file @code{file}. Only the first line will
2266
be read from file @code{file}. This can only be used if only one
2267
passphrase is supplied. Obviously, a passphrase stored in a file is
2268
of questionable security if other users can read this file. Don't use
2269
this option if you can avoid it.
2271
Note that this passphrase is only used if the option @option{--batch}
2272
has also been given. This is different from @command{gpg}.
2275
@item --passphrase @code{string}
2276
Use @code{string} as the passphrase. This can only be used if only one
2277
passphrase is supplied. Obviously, this is of very questionable
2278
security on a multi-user system. Don't use this option if you can
2281
Note that this passphrase is only used if the option @option{--batch}
2282
has also been given. This is different from @command{gpg}.
2285
@item --command-fd @code{n}
2286
This is a replacement for the deprecated shared-memory IPC mode.
2287
If this option is enabled, user input on questions is not expected
2288
from the TTY but from the given file descriptor. It should be used
2289
together with @option{--status-fd}. See the file doc/DETAILS in the source
2290
distribution for details on how to use it.
2292
@item --command-file @code{file}
2293
Same as @option{--command-fd}, except the commands are read out of file
2296
@item --allow-non-selfsigned-uid
2297
@itemx --no-allow-non-selfsigned-uid
2298
Allow the import and use of keys with user IDs which are not
2299
self-signed. This is not recommended, as a non self-signed user ID is
2300
trivial to forge. @option{--no-allow-non-selfsigned-uid} disables.
2302
@item --allow-freeform-uid
2303
Disable all checks on the form of the user ID while generating a new
2304
one. This option should only be used in very special environments as
2305
it does not ensure the de-facto standard format of user IDs.
2307
@item --ignore-time-conflict
2308
GnuPG normally checks that the timestamps associated with keys and
2309
signatures have plausible values. However, sometimes a signature
2310
seems to be older than the key due to clock problems. This option
2311
makes these checks just a warning. See also @option{--ignore-valid-from} for
2312
timestamp issues on subkeys.
2314
@item --ignore-valid-from
2315
GnuPG normally does not select and use subkeys created in the future.
2316
This option allows the use of such keys and thus exhibits the
2317
pre-1.0.7 behaviour. You should not use this option unless you there
2318
is some clock problem. See also @option{--ignore-time-conflict} for timestamp
2319
issues with signatures.
2321
@item --ignore-crc-error
2322
The ASCII armor used by OpenPGP is protected by a CRC checksum against
2323
transmission errors. Occasionally the CRC gets mangled somewhere on
2324
the transmission channel but the actual content (which is protected by
2325
the OpenPGP protocol anyway) is still okay. This option allows GnuPG
2326
to ignore CRC errors.
2328
@item --ignore-mdc-error
2329
This option changes a MDC integrity protection failure into a warning.
2330
This can be useful if a message is partially corrupt, but it is
2331
necessary to get as much data as possible out of the corrupt message.
2332
However, be aware that a MDC protection failure may also mean that the
2333
message was tampered with intentionally by an attacker.
2335
@item --no-default-keyring
2336
Do not add the default keyrings to the list of keyrings. Note that
2337
GnuPG will not operate without any keyrings, so if you use this option
2338
and do not provide alternate keyrings via @option{--keyring} or
2339
@option{--secret-keyring}, then GnuPG will still use the default public or
2343
Skip the signature verification step. This may be
2344
used to make the decryption faster if the signature
2345
verification is not needed.
2347
@item --with-key-data
2348
Print key listings delimited by colons (like @option{--with-colons}) and
2349
print the public key data.
2351
@item --fast-list-mode
2352
Changes the output of the list commands to work faster; this is achieved
2353
by leaving some parts empty. Some applications don't need the user ID
2354
and the trust information given in the listings. By using this options
2355
they can get a faster listing. The exact behaviour of this option may
2356
change in future versions. If you are missing some information, don't
2360
This is not for normal use. Use the source to see for what it might be useful.
2362
@item --set-filesize
2363
This is not for normal use. Use the source to see for what it might be useful.
2365
@item --show-session-key
2366
Display the session key used for one message. See
2367
@option{--override-session-key} for the counterpart of this option.
2369
We think that Key Escrow is a Bad Thing; however the user should have
2370
the freedom to decide whether to go to prison or to reveal the content
2371
of one specific message without compromising all messages ever
2372
encrypted for one secret key. DON'T USE IT UNLESS YOU ARE REALLY
2375
@item --override-session-key @code{string}
2376
Don't use the public key but the session key @code{string}. The format
2377
of this string is the same as the one printed by
2378
@option{--show-session-key}. This option is normally not used but comes
2379
handy in case someone forces you to reveal the content of an encrypted
2380
message; using this option you can do this without handing out the
2383
@item --ask-sig-expire
2384
@itemx --no-ask-sig-expire
2385
When making a data signature, prompt for an expiration time. If this
2386
option is not specified, the expiration time set via
2387
@option{--default-sig-expire} is used. @option{--no-ask-sig-expire}
2388
disables this option. Note that by default, @option{--force-v3-sigs} is
2389
set which also disables this option. If you want signature expiration,
2390
you must set @option{--no-force-v3-sigs} as well as turning
2391
@option{--ask-sig-expire} on.
2393
@item --default-sig-expire
2394
The default expiration time to use for signature expiration. Valid
2395
values are "0" for no expiration, a number followed by the letter d
2396
(for days), w (for weeks), m (for months), or y (for years) (for
2397
example "2m" for two months, or "5y" for five years), or an absolute
2398
date in the form YYYY-MM-DD. Defaults to "0".
2400
@item --ask-cert-expire
2401
@itemx --no-ask-cert-expire
2402
When making a key signature, prompt for an expiration time. If this
2403
option is not specified, the expiration time set via
2404
@option{--default-cert-expire} is used. @option{--no-ask-cert-expire}
2405
disables this option.
2407
@item --default-cert-expire
2408
The default expiration time to use for key signature expiration.
2409
Valid values are "0" for no expiration, a number followed by the
2410
letter d (for days), w (for weeks), m (for months), or y (for years)
2411
(for example "2m" for two months, or "5y" for five years), or an
2412
absolute date in the form YYYY-MM-DD. Defaults to "0".
2414
@item --allow-secret-key-import
2415
This is an obsolete option and is not used anywhere.
2417
@item --allow-multiple-messages
2418
@item --no-allow-multiple-messages
2419
Allow processing of multiple OpenPGP messages contained in a single
2420
file or stream. Some programs that call GPG are not prepared to deal
2421
with multiple messages being processed together, so this option
2422
defaults to no. Note that versions of GPG prior to 1.4.7 always
2423
allowed multiple messages.
2425
@item --enable-special-filenames
2426
This options enables a mode in which filenames of the form
2427
@file{-&n}, where n is a non-negative decimal number,
2428
refer to the file descriptor n and not to a file with that name.
2430
@item --no-expensive-trust-checks
2431
Experimental use only.
2433
@item --preserve-permissions
2434
Don't change the permissions of a secret keyring back to user
2435
read/write only. Use this option only if you really know what you are doing.
2437
@item --default-preference-list @code{string}
2438
@opindex default-preference-list
2439
Set the list of default preferences to @code{string}. This preference
2440
list is used for new keys and becomes the default for "setpref" in the
2443
@item --default-keyserver-url @code{name}
2444
@opindex default-keyserver-url
2445
Set the default keyserver URL to @code{name}. This keyserver will be
2446
used as the keyserver URL when writing a new self-signature on a key,
2447
which includes key generation and changing preferences.
2450
@opindex list-config
2451
Display various internal configuration parameters of GnuPG. This option
2452
is intended for external programs that call GnuPG to perform tasks, and
2453
is thus not generally useful. See the file @file{doc/DETAILS} in the
2454
source distribution for the details of which configuration items may be
2455
listed. @option{--list-config} is only usable with
2456
@option{--with-colons} set.
2458
@item --gpgconf-list
2459
@opindex gpgconf-list
2460
This command is similar to @option{--list-config} but in general only
2461
internally used by the @command{gpgconf} tool.
2463
@item --gpgconf-test
2464
@opindex gpgconf-test
2465
This is more or less dummy action. However it parses the configuration
2466
file and returns with failure if the configuration file would prevent
2467
@command{gpg} from startup. Thus it may be used to run a syntax check
2468
on the configuration file.
2472
@c *******************************
2473
@c ******* Deprecated ************
2474
@c *******************************
2475
@subsection Deprecated options
2480
@item --load-extension @code{name}
2481
Load an extension module. If @code{name} does not contain a slash it is
2482
searched for in the directory configured when GnuPG was built
2483
(generally "/usr/local/lib/gnupg"). Extensions are not generally
2484
useful anymore, and the use of this option is deprecated.
2488
@itemx --no-show-photos
2489
Causes @option{--list-keys}, @option{--list-sigs},
2490
@option{--list-public-keys}, @option{--list-secret-keys}, and verifying
2491
a signature to also display the photo ID attached to the key, if
2492
any. See also @option{--photo-viewer}. These options are deprecated. Use
2493
@option{--list-options [no-]show-photos} and/or @option{--verify-options
2494
[no-]show-photos} instead.
2496
@item --show-keyring
2497
Display the keyring name at the head of key listings to show which
2498
keyring a given key resides on. This option is deprecated: use
2499
@option{--list-options [no-]show-keyring} instead.
2502
@item --ctapi-driver @code{file}
2503
Use @code{file} to access the smartcard reader. The current default
2504
is `libtowitoko.so'. Note that the use of this interface is
2505
deprecated; it may be removed in future releases.
2508
@item --always-trust
2509
Identical to @option{--trust-model always}. This option is deprecated.
2511
@item --show-notation
2512
@itemx --no-show-notation
2513
Show signature notations in the @option{--list-sigs} or @option{--check-sigs} listings
2514
as well as when verifying a signature with a notation in it. These
2515
options are deprecated. Use @option{--list-options [no-]show-notation}
2516
and/or @option{--verify-options [no-]show-notation} instead.
2518
@item --show-policy-url
2519
@itemx --no-show-policy-url
2520
Show policy URLs in the @option{--list-sigs} or @option{--check-sigs}
2521
listings as well as when verifying a signature with a policy URL in
2522
it. These options are deprecated. Use @option{--list-options
2523
[no-]show-policy-url} and/or @option{--verify-options
2524
[no-]show-policy-url} instead.
2530
@c *******************************************
2531
@c *************** ****************
2532
@c *************** FILES ****************
2533
@c *************** ****************
2534
@c *******************************************
2536
@node GPG Configuration
2537
@section Configuration files
2539
There are a few configuration files to control certain aspects of
2540
@command{@gpgname}'s operation. Unless noted, they are expected in the
2541
current home directory (@pxref{option --homedir}).
2547
This is the standard configuration file read by @command{@gpgname} on
2548
startup. It may contain any valid long option; the leading two dashes
2549
may not be entered and the option may not be abbreviated. This default
2550
name may be changed on the command line (@pxref{option
2556
Note that on larger installations, it is useful to put predefined files
2557
into the directory @file{/etc/skel/.gnupg/} so that newly created users
2558
start up with a working configuration.
2560
For existing users the a small
2561
helper script is provided to create these files (@pxref{addgnupghome}).
2564
For internal purposes @command{@gpgname} creates and maintains a few other
2565
files; They all live in in the current home directory (@pxref{option
2566
--homedir}). Only the @command{@gpgname} may modify these files.
2570
@item ~/.gnupg/secring.gpg
2573
@item ~/.gnupg/secring.gpg.lock
2576
@item ~/.gnupg/pubring.gpg
2579
@item ~/.gnupg/pubring.gpg.lock
2582
@item ~/.gnupg/trustdb.gpg
2585
@item ~/.gnupg/trustdb.gpg.lock
2588
@item ~/.gnupg/random_seed
2589
used to preserve the internal random pool
2591
@item /usr[/local]/share/gnupg/options.skel
2592
Skeleton options file
2594
@item /usr[/local]/lib/gnupg/
2595
Default location for extensions
2600
Operation is further controlled by a few environment variables:
2605
Used to locate the default home directory.
2608
If set directory used instead of "~/.gnupg".
2610
@item GPG_AGENT_INFO
2611
Used to locate the gpg-agent.
2613
This is only honored when @option{--use-agent} is set.
2615
The value consists of 3 colon delimited fields: The first is the path
2616
to the Unix Domain Socket, the second the PID of the gpg-agent and the
2617
protocol version which should be set to 1. When starting the gpg-agent
2618
as described in its documentation, this variable is set to the correct
2619
value. The option @option{--gpg-agent-info} can be used to override it.
2621
@item PINENTRY_USER_DATA
2622
This value is passed via gpg-agent to pinentry. It is useful to convey
2623
extra information to a custom pinentry
2627
Used to size some displays to the full size of the screen.
2631
Apart from its use by GNU, it is used in the W32 version to override the
2632
language selection done through the Registry. If used and set to a a
2633
valid and available language name (@var{langid}), the file with the
2634
translation is loaded from
2635
@code{@var{gpgdir}/gnupg.nls/@var{langid}.mo}. Here @var{gpgdir} is the
2636
directory out of which the gpg binary has been laoded. If it can't be
2637
loaded the Registry is tried and as last resort the native Windows
2638
locale system is used.
2643
@c *******************************************
2644
@c *************** ****************
2645
@c *************** EXAMPLES ****************
2646
@c *************** ****************
2647
@c *******************************************
2654
@item gpg -se -r @code{Bob} @code{file}
2655
sign and encrypt for user Bob
2657
@item gpg --clearsign @code{file}
2658
make a clear text signature
2660
@item gpg -sb @code{file}
2661
make a detached signature
2663
@item gpg --list-keys @code{user_ID}
2666
@item gpg --fingerprint @code{user_ID}
2669
@item gpg --verify @code{pgpfile}
2670
@itemx gpg --verify @code{sigfile}
2671
Verify the signature of the file but do not output the data. The
2672
second form is used for detached signatures, where @code{sigfile}
2673
is the detached signature (either ASCII armored or binary) and
2674
are the signed data; if this is not given, the name of
2675
the file holding the signed data is constructed by cutting off the
2676
extension (".asc" or ".sig") of @code{sigfile} or by asking the
2677
user for the filename.
2681
@c *******************************************
2682
@c *************** ****************
2683
@c *************** USER ID ****************
2684
@c *************** ****************
2685
@c *******************************************
2686
@mansect how to specify a user id
2688
@include specify-user-id.texi
2691
@mansect return value
2692
@chapheading RETURN VALUE
2694
The program returns 0 if everything was fine, 1 if at least
2695
a signature was bad, and other error codes for fatal errors.
2698
@chapheading WARNINGS
2700
Use a *good* password for your user account and a *good* passphrase
2701
to protect your secret key. This passphrase is the weakest part of the
2702
whole system. Programs to do dictionary attacks on your secret keyring
2703
are very easy to write and so you should protect your "~/.gnupg/"
2704
directory very well.
2706
Keep in mind that, if this program is used over a network (telnet), it
2707
is *very* easy to spy out your passphrase!
2709
If you are going to verify detached signatures, make sure that the
2710
program knows about it; either give both filenames on the command line
2711
or use @samp{-} to specify stdin.
2713
@mansect interoperability
2714
@chapheading INTEROPERABILITY WITH OTHER OPENPGP PROGRAMS
2716
GnuPG tries to be a very flexible implementation of the OpenPGP
2717
standard. In particular, GnuPG implements many of the optional parts
2718
of the standard, such as the SHA-512 hash, and the ZLIB and BZIP2
2719
compression algorithms. It is important to be aware that not all
2720
OpenPGP programs implement these optional algorithms and that by
2721
forcing their use via the @option{--cipher-algo},
2722
@option{--digest-algo}, @option{--cert-digest-algo}, or
2723
@option{--compress-algo} options in GnuPG, it is possible to create a
2724
perfectly valid OpenPGP message, but one that cannot be read by the
2727
There are dozens of variations of OpenPGP programs available, and each
2728
supports a slightly different subset of these optional algorithms.
2729
For example, until recently, no (unhacked) version of PGP supported
2730
the BLOWFISH cipher algorithm. A message using BLOWFISH simply could
2731
not be read by a PGP user. By default, GnuPG uses the standard
2732
OpenPGP preferences system that will always do the right thing and
2733
create messages that are usable by all recipients, regardless of which
2734
OpenPGP program they use. Only override this safe default if you
2735
really know what you are doing.
2737
If you absolutely must override the safe default, or if the preferences
2738
on a given key are invalid for some reason, you are far better off using
2739
the @option{--pgp6}, @option{--pgp7}, or @option{--pgp8} options. These
2740
options are safe as they do not force any particular algorithms in
2741
violation of OpenPGP, but rather reduce the available algorithms to a
2747
On many systems this program should be installed as setuid(root). This
2748
is necessary to lock memory pages. Locking memory pages prevents the
2749
operating system from writing memory pages (which may contain
2750
passphrases or other sensitive material) to disk. If you get no
2751
warning message about insecure memory your operating system supports
2752
locking without being root. The program drops root privileges as soon
2753
as locked memory is allocated.
2755
Note also that some systems (especially laptops) have the ability to
2756
``suspend to disk'' (also known as ``safe sleep'' or ``hibernate'').
2757
This writes all memory to disk before going into a low power or even
2758
powered off mode. Unless measures are taken in the operating system
2759
to protect the saved memory, passphrases or other sensitive material
2760
may be recoverable from it later.
2767
@command{gpg-agent}(1)
2770
@include see-also-note.texi
added
removed
doc/gpg.texi
