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1807 lines
68 KiB
Plaintext
\input texinfo
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@c This Texinfo document has been automatically generated by
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@c docbook2texi from a DocBook documentation. The tool used
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@c can be found at:
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@c <URL:http://shell.ipoline.com/~elmert/hacks/docbook2X/>
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@c Please send any bug reports, improvements, comments,
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@c patches, etc. to Steve Cheng <steve@ggi-project.org>.
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@setfilename gpg.info
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@dircategory GnuPG
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@direntry
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* gpg: (gpg). GnuPG encryption and signing tool.
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@end direntry
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@node top
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@top gpg
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@menu
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@end menu
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@majorheading Name
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gpg ---- encryption and signing tool</>
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@majorheading Synopsis
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@majorheading DESCRIPTION
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@code{gpg} is the main program for the GnuPG system.
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This man page only lists the commands and options available.
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For more verbose documentation get the GNU Privacy Handbook (GPH) or
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one of the other documents at http://www.gnupg.org/docs.html .
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Please remember that option parsing stops as soon as a non option is
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encountered, you can explicitly stop option parsing by using the
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special option "---".
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@majorheading COMMANDS
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@code{gpg} recognizes these commands:
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@table @asis
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@item -s, ---sign
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Make a signature. This command may be combined
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with ---encrypt.
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@item ---clearsign
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Make a clear text signature.
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@item -b, ---detach-sign
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Make a detached signature.
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@item -e, ---encrypt
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Encrypt data. This option may be combined with ---sign.
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@item -c, ---symmetric
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Encrypt with a symmetric cipher using a passphrase. The default
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symmetric cipher used is CAST5, but may be chosen with the
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---cipher-algo option.
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@item ---store
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Store only (make a simple RFC1991 packet).
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@item ---decrypt @code{file}
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Decrypt @code{file} (or stdin if no file is specified) and
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write it to stdout (or the file specified with
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---output). If the decrypted file is signed, the
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signature is also verified. This command differs
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from the default operation, as it never writes to the
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filename which is included in the file and it
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rejects files which don't begin with an encrypted
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message.
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@item ---verify @code{sigfile} @code{signed-files}
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Assume that @code{sigfile} is a signature and verify it
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without generating any output. With no arguments,
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the signature packet is read from stdin. If
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only a sigfile is given, it may be a complete
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signature or a detached signature, in which case
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the signed stuff is expected in a file without the
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".sig" or ".asc" extension.
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With more than
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1 argument, the first should be a detached signature
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and the remaining files are the signed stuff. To read the signed
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stuff from stdin, use @samp{-} as the second filename.
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For security reasons a detached signature cannot read the signed
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material from stdin without denoting it in the above way.
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@item ---verify-files @code{files}
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This is a special version of the ---verify command which does not work with
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detached signatures. The command expects the files to be verified either
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on the command line or reads the filenames from stdin; each name must be on
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separate line. The command is intended for quick checking of many files.
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@item ---encrypt-files @code{files}
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This is a special version of the ---encrypt command. The command expects
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the files to be encrypted either on the command line or reads the filenames
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from stdin; each name must be on separate line. The command is intended
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for a quick encryption of multiple files.
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@item ---decrypt-files @code{files}
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The same as ---encrypt-files with the difference that files will be
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decrypted. The syntax or the filenames is the same.
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@item ---list-keys @code{names}
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@itemx ---list-public-keys @code{names}
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List all keys from the public keyrings, or just the ones given on the
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command line.
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Avoid using the output of this command in scripts or other programs as
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it is likely to change as GnuPG changes. See ---with-colons for a
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machine-parseable key listing command that is appropriate for use in
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scripts and other programs.
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@item ---list-secret-keys @code{names}
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List all keys from the secret keyrings, or just the ones given on the
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command line. A '#' after the letters 'sec' means that the secret key
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is not usable (for example, if it was created via
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---export-secret-subkeys).
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@item ---list-sigs @code{names}
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Same as ---list-keys, but the signatures are listed too.
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For each signature listed, there are several flags in between the
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"sig" tag and keyid. These flags give additional information about
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each signature. From left to right, they are the numbers 1-3 for
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certificate check level (see ---default-cert-check-level), "L" for a
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local or non-exportable signature (see ---lsign-key), "R" for a
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nonRevocable signature (see ---nrsign-key), "P" for a signature that
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contains a policy URL (see ---cert-policy-url), "N" for a signature
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that contains a notation (see ---cert-notation), "X" for an eXpired
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signature (see ---ask-cert-expire), and the numbers 1-9 or "T" for 10
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and above to indicate trust signature levels (see the ---edit-key
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command "tsign").
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@item ---check-sigs @code{names}
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Same as ---list-sigs, but the signatures are verified.
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@item ---fingerprint @code{names}
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List all keys with their fingerprints. This is the
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same output as ---list-keys but with the additional output
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of a line with the fingerprint. May also be combined
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with ---list-sigs or --check-sigs.
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If this command is given twice, the fingerprints of all
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secondary keys are listed too.
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@item ---list-packets
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List only the sequence of packets. This is mainly
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useful for debugging.
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@item ---gen-key
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Generate a new key pair. This command is normally only used
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interactively.
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There is an experimental feature which allows you to create keys
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in batch mode. See the file @file{doc/DETAILS}
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in the source distribution on how to use this.
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@item ---edit-key @code{name}
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Present a menu which enables you to do all key
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related tasks:
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@table @asis
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@item sign
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Make a signature on key of user @code{name}
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If the key is not yet signed by the default
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user (or the users given with -u), the
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program displays the information of the key
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again, together with its fingerprint and
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asks whether it should be signed. This
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question is repeated for all users specified
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with -u.
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@item lsign
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Same as ---sign but the signature is marked as
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non-exportable and will therefore never be used
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by others. This may be used to make keys valid
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only in the local environment.
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@item nrsign
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Same as ---sign but the signature is marked as non-revocable and can
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therefore never be revoked.
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@item nrlsign
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Combines the functionality of nrsign and lsign to make a signature
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that is both non-revocable and
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non-exportable.
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@item tsign
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Make a trust signature. This is a signature that combines the notions
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of certification (like a regular signature), and trust (like the
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"trust" command). It is generally only useful in distinct communities
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or groups.
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@item revsig
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Revoke a signature. For every signature which has been generated by
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one of the secret keys, GnuPG asks whether a revocation certificate
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should be generated.
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@item trust
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Change the owner trust value. This updates the
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trust-db immediately and no save is required.
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@item disable
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@itemx enable
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Disable or enable an entire key. A disabled key can not normally be
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used for encryption.
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@item adduid
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Create an alternate user id.
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@item addphoto
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Create a photographic user id. This will prompt for a JPEG file that
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will be embedded into the user ID. A very large JPEG will make for a
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very large key.
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@item deluid
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Delete a user id.
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@item revuid
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Revoke a user id.
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@item addkey
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Add a subkey to this key.
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@item delkey
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Remove a subkey.
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@item addrevoker
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Add a designated revoker. This takes one optional argument:
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"sensitive". If a designated revoker is marked as sensitive, it will
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not be exported by default (see
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export-options).
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@item revkey
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Revoke a subkey.
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@item expire
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Change the key expiration time. If a subkey is selected, the
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expiration time of this subkey will be changed. With no selection,
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the key expiration of the primary key is changed.
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@item passwd
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Change the passphrase of the secret key.
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@item primary
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Flag the current user id as the primary one, removes the primary user
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id flag from all other user ids and sets the timestamp of all affected
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self-signatures one second ahead. Note that setting a photo user ID
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as primary makes it primary over other photo user IDs, and setting a
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regular user ID as primary makes it primary over other regular user
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IDs.
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@item uid @code{n}
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Toggle selection of user id with index @code{n}.
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Use 0 to deselect all.
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@item key @code{n}
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Toggle selection of subkey with index @code{n}.
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Use 0 to deselect all.
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@item check
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Check all selected user ids.
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@item showphoto
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Display the selected photographic user
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id.
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@item pref
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List preferences from the selected user ID. This shows the actual
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preferences, without including any implied preferences.
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@item showpref
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More verbose preferences listing for the selected user ID. This shows
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the preferences in effect by including the implied preferences of
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3DES (cipher), SHA-1 (digest), and Uncompressed (compression) if they
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are not already included in the preference list.
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@item setpref @code{string}
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Set the list of user ID preferences to @code{string}, this should be a
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string similar to the one printed by "pref". Using an empty string
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will set the default preference string, using "none" will set the
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preferences to nil. Use "gpg ---version" to get a list of available
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algorithms. This command just initializes an internal list and does
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not change anything unless another command (such as "updpref") which
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changes the self-signatures is used.
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@item updpref
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Change the preferences of all user IDs (or just of the selected ones
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to the current list of preferences. The timestamp of all affected
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self-signatures will be advanced by one second. Note that while you
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can change the preferences on an attribute user ID (aka "photo ID"),
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GnuPG does not select keys via attribute user IDs so these preferences
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will not be used by GnuPG.
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@item toggle
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Toggle between public and secret key listing.
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@item save
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Save all changes to the key rings and quit.
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@item quit
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Quit the program without updating the
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key rings.
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@end table
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The listing shows you the key with its secondary
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keys and all user ids. Selected keys or user ids
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are indicated by an asterisk. The trust value is
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displayed with the primary key: the first is the
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assigned owner trust and the second is the calculated
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trust value. Letters are used for the values:
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@table @asis
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@item -
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No ownertrust assigned / not yet calculated.
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@item e
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Trust
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calculation has failed; probably due to an expired key.
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@item q
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Not enough information for calculation.
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@item n
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Never trust this key.
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@item m
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Marginally trusted.
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@item f
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Fully trusted.
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@item u
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Ultimately trusted.
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@end table
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@item ---sign-key @code{name}
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Signs a public key with your secret key. This is a shortcut version of
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the subcommand "sign" from ---edit.
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@item ---lsign-key @code{name}
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Signs a public key with your secret key but marks it as
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non-exportable. This is a shortcut version of the subcommand "lsign"
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from ---edit.
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@item ---nrsign-key @code{name}
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Signs a public key with your secret key but marks it as non-revocable.
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This is a shortcut version of the subcommand "nrsign" from ---edit.
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@item ---delete-key @code{name}
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Remove key from the public keyring. In batch mode either ---yes is
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required or the key must be specified by fingerprint. This is a
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safeguard against accidental deletion of multiple keys.
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@item ---delete-secret-key @code{name}
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Remove key from the secret and public keyring. In batch mode the key
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must be specified by fingerprint.
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@item ---delete-secret-and-public-key @code{name}
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Same as ---delete-key, but if a secret key exists, it will be removed
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first. In batch mode the key must be specified by fingerprint.
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@item ---gen-revoke
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Generate a revocation certificate for the complete key. To revoke
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a subkey or a signature, use the ---edit command.
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@item ---desig-revoke
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Generate a designated revocation certificate for a key. This allows a
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user (with the permission of the keyholder) to revoke someone else's
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key.
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@item ---export @code{names}
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Either export all keys from all keyrings (default
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keyrings and those registered via option ---keyring),
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or if at least one name is given, those of the given
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name. The new keyring is written to stdout or to
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the file given with option "output". Use together
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with ---armor to mail those keys.
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@item ---send-keys @code{names}
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Same as ---export but sends the keys to a keyserver.
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Option ---keyserver must be used to give the name
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of this keyserver. Don't send your complete keyring
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to a keyserver - select only those keys which are new
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or changed by you.
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@item ---export-all @code{names}
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Same as ---export, but also exports keys which
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are not compatible with OpenPGP.
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@item ---export-secret-keys @code{names}
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@itemx ---export-secret-subkeys @code{names}
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Same as ---export, but exports the secret keys instead.
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This is normally not very useful and a security risk.
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The second form of the command has the special property to
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render the secret part of the primary key useless; this is
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a GNU extension to OpenPGP and other implementations can
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not be expected to successfully import such a key.
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See the option ---simple-sk-checksum if you want to import such an
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exported key with an older OpenPGP implementation.
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@item ---import @code{files}
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@itemx ---fast-import @code{files}
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Import/merge keys. This adds the given keys to the
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keyring. The fast version is currently just a synonym.
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There are a few other options which control how this command works.
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Most notable here is the ---merge-only option which does not insert new keys
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but does only the merging of new signatures, user-IDs and subkeys.
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@item ---recv-keys @code{key IDs}
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Import the keys with the given key IDs from a keyserver. Option
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---keyserver must be used to give the name of this keyserver.
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@item ---refresh-keys @code{key IDs}
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Request updates from a keyserver for keys that already exist on the
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local keyring. This is useful for updating a key with the latest
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signatures, user IDs, etc. Option ---keyserver must be used to give
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the name of this keyserver.
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@item ---search-keys @code{names}
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Search the keyserver for the given names. Multiple names given here
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will be joined together to create the search string for the keyserver.
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Option ---keyserver must be used to give the name of this keyserver.
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@item ---update-trustdb
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Do trust database maintenance. This command iterates over all keys
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and builds the Web-of-Trust. This is an interactive command because it
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may have to ask for the "ownertrust" values for keys. The user has to
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give an estimation of how far she trusts the owner of the displayed
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key to correctly certify (sign) other keys. GnuPG only asks for the
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ownertrust value if it has not yet been assigned to a key. Using the
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---edit-key menu, the assigned value can be changed at any time.
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@item ---check-trustdb
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Do trust database maintenance without user interaction. From time to
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time the trust database must be updated so that expired keys or
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signatures and the resulting changes in the Web-of-Trust can be
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tracked. Normally, GnuPG will calculate when this is required and do
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it automatically unless ---no-auto-check-trustdb is set. This command
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can be used to force a trust database check at any time. The
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processing is identical to that of ---update-trustdb but it skips keys
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with a not yet defined "ownertrust".
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For use with cron jobs, this command can be used together with ---batch
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in which case the trust database check is done only if a check is
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needed. To force a run even in batch mode add the option ---yes.
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@item ---export-ownertrust
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Send the ownertrust values to stdout. This is useful for backup
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purposes as these values are the only ones which can't be re-created
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from a corrupted trust DB.
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@item ---import-ownertrust @code{files}
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Update the trustdb with the ownertrust values stored
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in @code{files} (or stdin if not given); existing
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values will be overwritten.
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@item ---rebuild-keydb-caches
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When updating from version 1.0.6 to 1.0.7 this command should be used
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to create signature caches in the keyring. It might be handy in other
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situations too.
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@item ---print-md @code{algo} @code{files}
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@itemx ---print-mds @code{files}
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Print message digest of algorithm ALGO for all given files or stdin.
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With the second form (or a deprecated "*" as algo) digests for all
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available algorithms are printed.
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@item ---gen-random @code{0|1|2} @code{count}
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|
Emit COUNT random bytes of the given quality level. If count is not given
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or zero, an endless sequence of random bytes will be emitted.
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PLEASE, don't use this command unless you know what you are doing; it may
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remove precious entropy from the system!
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@item ---gen-prime @code{mode} @code{bits} @code{qbits}
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Use the source, Luke :-). The output format is still subject to change.
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@item ---version
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Print version information along with a list
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of supported algorithms.
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@item ---warranty
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Print warranty information.
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@item -h, ---help
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Print usage information. This is a really long list even though it
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doesn't list all options. For every option, consult this manual.
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@end table
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@majorheading OPTIONS
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|
Long options can be put in an options file (default
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"~/.gnupg/gpg.conf"). Short option names will not work - for example,
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|
"armor" is a valid option for the options file, while "a" is not. Do
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|
not write the 2 dashes, but simply the name of the option and any
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|
required arguments. Lines with a hash ('#') as the first
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non-white-space character are ignored. Commands may be put in this
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file too, but that is not generally useful as the command will execute
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automatically with every execution of gpg.
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@code{gpg} recognizes these options:
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@table @asis
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@item -a, ---armor
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Create ASCII armored output.
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@item -o, ---output @code{file}
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|
Write output to @code{file}.
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|
|
@item ---mangle-dos-filenames
|
|
@itemx ---no-mangle-dos-filenames
|
|
Older version of Windows cannot handle filenames with more than one
|
|
dot. ---mangle-dos-filenames causes GnuPG to replace (rather than add
|
|
to) the extension of an output filename to avoid this problem. This
|
|
option is off by default and has no effect on non-Windows platforms.
|
|
|
|
@item -u, ---local-user @code{name}
|
|
Use @code{name} as the user ID to sign.
|
|
This option is silently ignored for the list commands,
|
|
so that it can be used in an options file.
|
|
|
|
@item ---default-key @code{name}
|
|
Use @code{name} as default user ID for signatures. If this
|
|
is not used the default user ID is the first user ID
|
|
found in the secret keyring.
|
|
|
|
@item -r, ---recipient @code{name}
|
|
@itemx
|
|
Encrypt for user id @code{name}. If this option or ---hidden-recipient
|
|
is not specified, GnuPG asks for the user-id unless
|
|
---default-recipient is given.
|
|
|
|
@item -R, ---hidden-recipient @code{name}
|
|
@itemx
|
|
Encrypt for user id @code{name}, but hide the keyid of the key. This
|
|
option hides the receiver of the message and is a countermeasure
|
|
against traffic analysis. If this option or ---recipient is not
|
|
specified, GnuPG asks for the user-id unless ---default-recipient is
|
|
given.
|
|
|
|
@item ---default-recipient @code{name}
|
|
Use @code{name} as default recipient if option ---recipient is not used and
|
|
don't ask if this is a valid one. @code{name} must be non-empty.
|
|
|
|
@item ---default-recipient-self
|
|
Use the default key as default recipient if option ---recipient is not used and
|
|
don't ask if this is a valid one. The default key is the first one from the
|
|
secret keyring or the one set with ---default-key.
|
|
|
|
@item ---no-default-recipient
|
|
Reset ---default-recipient and --default-recipient-self.
|
|
|
|
@item ---encrypt-to @code{name}
|
|
Same as ---recipient but this one is intended for use
|
|
in the options file and may be used with
|
|
your own user-id as an "encrypt-to-self". These keys
|
|
are only used when there are other recipients given
|
|
either by use of ---recipient or by the asked user id.
|
|
No trust checking is performed for these user ids and
|
|
even disabled keys can be used.
|
|
|
|
@item ---hidden-encrypt-to @code{name}
|
|
Same as ---hidden-recipient but this one is intended for use in the
|
|
options file and may be used with your own user-id as a hidden
|
|
"encrypt-to-self". These keys are only used when there are other
|
|
recipients given either by use of ---recipient or by the asked user id.
|
|
No trust checking is performed for these user ids and even disabled
|
|
keys can be used.
|
|
|
|
@item ---no-encrypt-to
|
|
Disable the use of all ---encrypt-to and --hidden-encrypt-to keys.
|
|
|
|
@item -v, ---verbose
|
|
Give more information during processing. If used
|
|
twice, the input data is listed in detail.
|
|
|
|
@item -q, ---quiet
|
|
Try to be as quiet as possible.
|
|
|
|
@item -z @code{n}, ---compress @code{n}
|
|
Set compression level to @code{n}. A value of 0 for @code{n}
|
|
disables compression. Default is to use the default
|
|
compression level of zlib (normally 6).
|
|
|
|
@item -t, ---textmode
|
|
@itemx ---no-textmode
|
|
Use canonical text mode. ---no-textmode disables this option. If -t
|
|
(but not ---textmode) is used together with armoring and signing, this
|
|
enables clearsigned messages. This kludge is needed for command-line
|
|
compatibility with command-line versions of PGP; normally you would
|
|
use ---sign or --clearsign to select the type of the signature.
|
|
|
|
@item -n, ---dry-run
|
|
Don't make any changes (this is not completely implemented).
|
|
|
|
@item -i, ---interactive
|
|
Prompt before overwriting any files.
|
|
|
|
@item ---batch
|
|
@itemx ---no-batch
|
|
Use batch mode. Never ask, do not allow interactive commands.
|
|
---no-batch disables this option.
|
|
|
|
@item ---no-tty
|
|
Make sure that the TTY (terminal) is never used for any output.
|
|
This option is needed in some cases because GnuPG sometimes prints
|
|
warnings to the TTY if ---batch is used.
|
|
|
|
@item ---yes
|
|
Assume "yes" on most questions.
|
|
|
|
@item ---no
|
|
Assume "no" on most questions.
|
|
|
|
@item ---default-cert-check-level @code{n}
|
|
The default to use for the check level when signing a key.
|
|
|
|
0 means you make no particular claim as to how carefully you verified
|
|
the key.
|
|
|
|
1 means you believe the key is owned by the person who claims to own
|
|
it but you could not, or did not verify the key at all. This is
|
|
useful for a "persona" verification, where you sign the key of a
|
|
pseudonymous user.
|
|
|
|
2 means you did casual verification of the key. For example, this
|
|
could mean that you verified that the key fingerprint and checked the
|
|
user ID on the key against a photo ID.
|
|
|
|
3 means you did extensive verification of the key. For example, this
|
|
could mean that you verified the key fingerprint with the owner of the
|
|
key in person, and that you checked, by means of a hard to forge
|
|
document with a photo ID (such as a passport) that the name of the key
|
|
owner matches the name in the user ID on the key, and finally that you
|
|
verified (by exchange of email) that the email address on the key
|
|
belongs to the key owner.
|
|
|
|
Note that the examples given above for levels 2 and 3 are just that:
|
|
examples. In the end, it is up to you to decide just what "casual"
|
|
and "extensive" mean to you.
|
|
|
|
This option defaults to 0.
|
|
|
|
@item ---trusted-key @code{long key ID}
|
|
Assume that the specified key (which must be given
|
|
as a full 8 byte key ID) is as trustworthy as one of
|
|
your own secret keys. This option is useful if you
|
|
don't want to keep your secret keys (or one of them)
|
|
online but still want to be able to check the validity of a given
|
|
recipient's or signator's key.
|
|
|
|
@item ---trust-model @code{pgp|classic|always}
|
|
Set what trust model GnuPG should follow. The models are:
|
|
|
|
@table @asis
|
|
@item pgp
|
|
This is the web-of-trust combined with trust signatures as used in PGP
|
|
5.x and later. This is the default trust model.
|
|
|
|
@item classic
|
|
This is the standard web-of-trust as used in PGP 2.x and earlier.
|
|
|
|
@item always
|
|
Skip key validation and assume that used keys are always fully
|
|
trusted. You won't use this unless you have installed some external
|
|
validation scheme. This option also suppresses the "[uncertain]" tag
|
|
printed with signature checks when there is no evidence that the user
|
|
ID is bound to the key.
|
|
|
|
@end table
|
|
|
|
@item ---always-trust
|
|
Identical to `---trust-model always'
|
|
|
|
@item ---keyserver @code{name}
|
|
Use @code{name} as your keyserver. This is the server that ---recv-keys,
|
|
---send-keys, and --search-keys will communicate with to receive keys
|
|
from, send keys to, and search for keys on. The format of the
|
|
@code{name} is a URI: `scheme:[//]keyservername[:port]' The scheme is
|
|
the type of keyserver: "hkp" for the Horowitz (or compatible)
|
|
keyservers, "ldap" for the NAI LDAP keyserver, or "mailto" for the
|
|
Horowitz email keyserver. Note that your particular installation of
|
|
GnuPG may have other keyserver types available as well. Keyserver
|
|
schemes are case-insensitive.
|
|
|
|
Most keyservers synchronize with each other, so there is generally no
|
|
need to send keys to more than one server. Using the command "host -l
|
|
pgp.net | grep wwwkeys" gives you a list of HKP keyservers. When
|
|
using one of the wwwkeys servers, due to load balancing using
|
|
round-robin DNS you may notice that you get a different key server
|
|
each time.
|
|
|
|
@item ---keyserver-options @code{parameters}
|
|
This is a space or comma delimited string that gives options for the
|
|
keyserver. Options can be prepended with a `no-' to give the opposite
|
|
meaning. Valid import-options or export-options may be used here as
|
|
well to apply to importing (---recv-key) or exporting (--send-key) a
|
|
key from a keyserver. While not all options are available for all
|
|
keyserver types, some common options are:
|
|
|
|
@table @asis
|
|
@item include-revoked
|
|
When searching for a key with ---search-keys, include keys that are
|
|
marked on the keyserver as revoked. Note that this option is always
|
|
set when using the NAI HKP keyserver, as this keyserver does not
|
|
differentiate between revoked and unrevoked keys.
|
|
|
|
@item include-disabled
|
|
When searching for a key with ---search-keys, include keys that are
|
|
marked on the keyserver as disabled. Note that this option is not
|
|
used with HKP keyservers.
|
|
|
|
@item include-subkeys
|
|
When receiving a key, include subkeys as potential targets. Note that
|
|
this option is not used with HKP keyservers, as they do not support
|
|
retrieving keys by subkey id.
|
|
|
|
@item use-temp-files
|
|
On most Unix-like platforms, GnuPG communicates with the keyserver
|
|
helper program via pipes, which is the most efficient method. This
|
|
option forces GnuPG to use temporary files to communicate. On some
|
|
platforms (such as Win32 and RISC OS), this option is always enabled.
|
|
|
|
@item keep-temp-files
|
|
If using `use-temp-files', do not delete the temp files after using
|
|
them. This option is useful to learn the keyserver communication
|
|
protocol by reading the temporary files.
|
|
|
|
@item verbose
|
|
Tell the keyserver helper program to be more verbose. This option can
|
|
be repeated multiple times to increase the verbosity level.
|
|
|
|
@item honor-http-proxy
|
|
For keyserver schemes that use HTTP (such as HKP), try to access the
|
|
keyserver over the proxy set with the environment variable
|
|
"http_proxy".
|
|
|
|
@item auto-key-retrieve
|
|
This option enables the automatic retrieving of keys from a keyserver
|
|
when verifying signatures made by keys that are not on the local
|
|
keyring.
|
|
|
|
Note that this option makes a "web bug" like behavior possible.
|
|
Keyserver operators can see which keys you request, so by sending you
|
|
a message signed by a brand new key (which you naturally will not have
|
|
on your local keyring), the operator can tell both your IP address and
|
|
the time when you verified the signature.
|
|
|
|
@end table
|
|
|
|
@item ---import-options @code{parameters}
|
|
This is a space or comma delimited string that gives options for
|
|
importing keys. Options can be prepended with a `no-' to give the
|
|
opposite meaning. The options are:
|
|
|
|
@table @asis
|
|
@item allow-local-sigs
|
|
Allow importing key signatures marked as "local". This is not
|
|
generally useful unless a shared keyring scheme is being used.
|
|
Defaults to no.
|
|
|
|
@item repair-pks-subkey-bug
|
|
During import, attempt to repair the damage caused by the PKS
|
|
keyserver bug (pre version 0.9.6) that mangles keys with multiple
|
|
subkeys. Note that this cannot completely repair the damaged key as
|
|
some crucial data is removed by the keyserver, but it does at least
|
|
give you back one subkey. Defaults to no for regular ---import and to
|
|
yes for keyserver ---recv-keys.
|
|
|
|
@end table
|
|
|
|
@item ---export-options @code{parameters}
|
|
This is a space or comma delimited string that gives options for
|
|
exporting keys. Options can be prepended with a `no-' to give the
|
|
opposite meaning. The options are:
|
|
|
|
@table @asis
|
|
@item include-non-rfc
|
|
Include non-RFC compliant keys in the export. Defaults to yes.
|
|
|
|
@item include-local-sigs
|
|
Allow exporting key signatures marked as "local". This is not
|
|
generally useful unless a shared keyring scheme is being used.
|
|
Defaults to no.
|
|
|
|
@item include-attributes
|
|
Include attribute user IDs (photo IDs) while exporting. This is
|
|
useful to export keys if they are going to be used by an OpenPGP
|
|
program that does not accept attribute user IDs. Defaults to yes.
|
|
|
|
@item include-sensitive-revkeys
|
|
Include designated revoker information that was marked as
|
|
"sensitive". Defaults to no.
|
|
|
|
@end table
|
|
|
|
@item ---list-options @code{parameters}
|
|
This is a space or comma delimited string that gives options used when
|
|
listing keys and signatures (that is, ---list-keys, --list-sigs,
|
|
---list-public-keys, --list-secret-keys, and the --edit-key functions).
|
|
Options can be prepended with a `no-' to give the opposite meaning.
|
|
The options are:
|
|
|
|
@table @asis
|
|
@item show-photos
|
|
Causes ---list-keys, --list-sigs, --list-public-keys, and
|
|
---list-secret-keys to display any photo IDs attached to the key.
|
|
Defaults to no. See also ---photo-viewer.
|
|
|
|
@item show-policy-url
|
|
Show policy URLs in the ---list-sigs or --check-sigs listings.
|
|
Defaults to no.
|
|
|
|
@item show-notation
|
|
Show signature notations in the ---list-sigs or --check-sigs listings.
|
|
Defaults to no.
|
|
|
|
@item show-keyserver-url
|
|
Show any preferred keyserver URL in the ---list-sigs or --check-sigs
|
|
listings. Defaults to no.
|
|
|
|
@item show-validity
|
|
Display the calculated validity of keys and user IDs during key
|
|
listings. Defaults to no.
|
|
|
|
@item show-long-keyid
|
|
Display all 64 bits (16 digits) of key IDs during key listings, rather
|
|
than the more common 32 bit (8 digit) IDs. Defaults to no.
|
|
|
|
@item show-unusable-uids
|
|
Show revoked and expired user IDs in key listings. Defaults to no.
|
|
|
|
@item show-keyring
|
|
Display the keyring name at the head of key listings to show which
|
|
keyring a given key resides on. Defaults to no.
|
|
|
|
@item show-sig-expire
|
|
Show signature expiration dates (if any) during ---list-sigs or
|
|
---check-sigs listings. Defaults to no.
|
|
|
|
@end table
|
|
|
|
@item ---verify-options @code{parameters}
|
|
This is a space or comma delimited string that gives options used when
|
|
verifying signatures. Options can be prepended with a `no-' to give
|
|
the opposite meaning. The options are:
|
|
|
|
@table @asis
|
|
@item show-photos
|
|
Display any photo IDs present on the key that issued the signature.
|
|
Defaults to no. See also ---photo-viewer.
|
|
|
|
@item show-policy-url
|
|
Show policy URLs in the signature being verified. Defaults to no.
|
|
|
|
@item show-notation
|
|
Show signature notations in the signature being verified. Defaults to
|
|
no.
|
|
|
|
@item show-keyserver-url
|
|
Show any preferred keyserver URL in the signature being verified.
|
|
Defaults to no.
|
|
|
|
@item show-validity
|
|
Display the calculated validity of the user IDs on the key that issued
|
|
the signature. Defaults to no.
|
|
|
|
@item show-long-keyid
|
|
Display all 64 bits (16 digits) of key IDs during signature
|
|
verification, rather than the more common 32 bit (8 digit) IDs.
|
|
Defaults to no.
|
|
|
|
@item show-unusable-uids
|
|
Show revoked and expired user IDs during signature verification.
|
|
Defaults to no.
|
|
|
|
@end table
|
|
|
|
@item ---show-photos
|
|
@itemx ---no-show-photos
|
|
Causes ---list-keys, --list-sigs, --list-public-keys,
|
|
---list-secret-keys, and verifying a signature to also display the
|
|
photo ID attached to the key, if any. See also ---photo-viewer. These
|
|
options are deprecated. Use `---list-options [no-]show-photos' and/or
|
|
`---verify-options [no-]show-photos' instead.
|
|
|
|
@item ---photo-viewer @code{string}
|
|
This is the command line that should be run to view a photo ID. "%i"
|
|
will be expanded to a filename containing the photo. "%I" does the
|
|
same, except the file will not be deleted once the viewer exits.
|
|
Other flags are "%k" for the key ID, "%K" for the long key ID, "%f"
|
|
for the key fingerprint, "%t" for the extension of the image type
|
|
(e.g. "jpg"), "%T" for the MIME type of the image (e.g. "image/jpeg"),
|
|
and "%%" for an actual percent sign. If neither %i or %I are present,
|
|
then the photo will be supplied to the viewer on standard input.
|
|
|
|
The default viewer is "xloadimage -fork -quiet -title 'KeyID 0x%k'
|
|
stdin". Note that if your image viewer program is not secure, then
|
|
executing it from GnuPG does not make it secure.
|
|
|
|
@item ---exec-path @code{string}
|
|
Sets a list of directories to search for photo viewers and keyserver
|
|
helpers. If not provided, keyserver helpers use the compiled-in
|
|
default directory, and photo viewers use the $PATH environment
|
|
variable.
|
|
|
|
@item ---show-keyring
|
|
Display the keyring name at the head of key listings to show which
|
|
keyring a given key resides on. This option is deprecated: use
|
|
`---list-options [no-]show-keyring' instead.
|
|
|
|
@item ---keyring @code{file}
|
|
Add @code{file} to the list of keyrings. If @code{file} begins with a
|
|
tilde and a slash, these are replaced by the HOME directory. If the
|
|
filename does not contain a slash, it is assumed to be in the GnuPG
|
|
home directory ("~/.gnupg" if ---homedir is not used). The filename
|
|
may be prefixed with a scheme:
|
|
|
|
"gnupg-ring:" is the default one.
|
|
|
|
It might make sense to use it together with ---no-default-keyring.
|
|
|
|
@item ---secret-keyring @code{file}
|
|
Same as ---keyring but for the secret keyrings.
|
|
|
|
@item ---primary-keyring @code{file}
|
|
Designate @code{file} as the primary public keyring. This means that
|
|
newly imported keys (via ---import or keyserver --recv-from) will go to
|
|
this keyring.
|
|
|
|
@item ---trustdb-name @code{file}
|
|
Use @code{file} instead of the default trustdb. If @code{file} begins
|
|
with a tilde and a slash, these are replaced by the HOME directory. If
|
|
the filename does not contain a slash, it is assumed to be in the
|
|
GnuPG home directory ("~/.gnupg" if ---homedir is not used).
|
|
|
|
@item ---homedir @code{directory}
|
|
Set the name of the home directory to @code{directory} If this
|
|
option is not used it defaults to "~/.gnupg". It does
|
|
not make sense to use this in a options file. This
|
|
also overrides the environment variable "GNUPGHOME".
|
|
|
|
@item ---charset @code{name}
|
|
Set the name of the native character set. This is used
|
|
to convert some strings to proper UTF-8 encoding. If this option is not used, the default character set is determined
|
|
from the current locale. A verbosity level of 3 shows the used one.
|
|
Valid values for @code{name} are:
|
|
|
|
@table @asis
|
|
@item iso-8859-1
|
|
This is the Latin 1 set.
|
|
|
|
@item iso-8859-2
|
|
The Latin 2 set.
|
|
|
|
@item iso-8859-15
|
|
This is currently an alias for
|
|
the Latin 1 set.
|
|
|
|
@item koi8-r
|
|
The usual Russian set (rfc1489).
|
|
|
|
@item utf-8
|
|
Bypass all translations and assume
|
|
that the OS uses native UTF-8 encoding.
|
|
|
|
@end table
|
|
|
|
@item ---utf8-strings
|
|
@itemx ---no-utf8-strings
|
|
Assume that the arguments are already given as UTF8 strings. The default
|
|
(---no-utf8-strings)
|
|
is to assume that arguments are encoded in the character set as specified
|
|
by ---charset. These options affect all following arguments. Both options may
|
|
be used multiple times.
|
|
|
|
@item ---options @code{file}
|
|
Read options from @code{file} and do not try to read
|
|
them from the default options file in the homedir
|
|
(see ---homedir). This option is ignored if used
|
|
in an options file.
|
|
|
|
@item ---no-options
|
|
Shortcut for "---options /dev/null". This option is
|
|
detected before an attempt to open an option file.
|
|
Using this option will also prevent the creation of a
|
|
"~./gnupg" homedir.
|
|
|
|
@item ---load-extension @code{name}
|
|
Load an extension module. If @code{name} does not contain a slash it is
|
|
searched for in the directory configured when GnuPG was built
|
|
(generally "/usr/local/lib/gnupg"). Extensions are not generally
|
|
useful anymore, and the use of this option is deprecated.
|
|
|
|
@item ---debug @code{flags}
|
|
Set debugging flags. All flags are or-ed and @code{flags} may
|
|
be given in C syntax (e.g. 0x0042).
|
|
|
|
@item ---debug-all
|
|
Set all useful debugging flags.
|
|
|
|
@item ---enable-progress-filter
|
|
Enable certain PROGRESS status outputs. This option allows frontends
|
|
to display a progress indicator while gpg is processing larger files.
|
|
There is a slight performance overhead using it.
|
|
|
|
@item ---status-fd @code{n}
|
|
Write special status strings to the file descriptor @code{n}.
|
|
See the file DETAILS in the documentation for a listing of them.
|
|
|
|
@item ---logger-fd @code{n}
|
|
Write log output to file descriptor @code{n} and not to stderr.
|
|
|
|
@item ---attribute-fd @code{n}
|
|
Write attribute subpackets to the file descriptor @code{n}. This is
|
|
most useful for use with ---status-fd, since the status messages are
|
|
needed to separate out the various subpackets from the stream
|
|
delivered to the file descriptor.
|
|
|
|
@item ---sk-comments
|
|
@itemx ---no-sk-comments
|
|
Include secret key comment packets when exporting secret keys. This
|
|
is a GnuPG extension to the OpenPGP standard, and is off by default.
|
|
Please note that this has nothing to do with the comments in clear
|
|
text signatures or armor headers. ---no-sk-comments disables this
|
|
option.
|
|
|
|
@item ---comment @code{string}
|
|
@itemx ---no-comments
|
|
Use @code{string} as a comment string in clear text signatures and
|
|
ASCII armored messages or keys (see ---armor). The default behavior is
|
|
not to use a comment string. ---comment may be repeated multiple times
|
|
to get multiple comment strings. ---no-comments removes all comments.
|
|
|
|
@item ---emit-version
|
|
@itemx ---no-emit-version
|
|
Force inclusion of the version string in ASCII armored output.
|
|
---no-emit-version disables this option.
|
|
|
|
@item ---sig-notation @code{name=value}
|
|
@itemx ---cert-notation @code{name=value}
|
|
@itemx -N, ---set-notation @code{name=value}
|
|
Put the name value pair into the signature as notation data.
|
|
@code{name} must consist only of printable characters or spaces, and
|
|
must contain a '@@' character. This is to help prevent pollution of
|
|
the IETF reserved notation namespace. The ---expert flag overrides the
|
|
'@@' check. @code{value} may be any printable string; it will be
|
|
encoded in UTF8, so you should check that your ---charset is set
|
|
correctly. If you prefix @code{name} with an exclamation mark, the
|
|
notation data will be flagged as critical (rfc2440:5.2.3.15).
|
|
---sig-notation sets a notation for data signatures. --cert-notation
|
|
sets a notation for key signatures (certifications). ---set-notation
|
|
sets both.
|
|
|
|
There are special codes that may be used in notation names. "%k" will
|
|
be expanded into the key ID of the key being signed, "%K" into the
|
|
long key ID of the key being signed, "%f" into the fingerprint of the
|
|
key being signed, "%s" into the key ID of the key making the
|
|
signature, "%S" into the long key ID of the key making the signature,
|
|
"%g" into the fingerprint of the key making the signature (which might
|
|
be a subkey), "%p" into the fingerprint of the primary key of the key
|
|
making the signature, and "%%" results in a single "%". %k, %K, and
|
|
%f are only meaningful when making a key signature (certification).
|
|
|
|
@item ---show-notation
|
|
@itemx ---no-show-notation
|
|
Show signature notations in the ---list-sigs or --check-sigs listings
|
|
as well as when verifying a signature with a notation in it. These
|
|
options are deprecated. Use `---list-options [no-]show-notation'
|
|
and/or `---verify-options [no-]show-notation' instead.
|
|
|
|
@item ---sig-policy-url @code{string}
|
|
@itemx ---cert-policy-url @code{string}
|
|
@itemx ---set-policy-url @code{string}
|
|
Use @code{string} as a Policy URL for signatures (rfc2440:5.2.3.19).
|
|
If you prefix it with an exclamation mark, the policy URL packet will
|
|
be flagged as critical. ---sig-policy-url sets a a policy url for data
|
|
signatures. ---cert-policy-url sets a policy url for key signatures
|
|
(certifications). ---set-policy-url sets both.
|
|
|
|
The same %-expandos used for notation data are available here as well.
|
|
|
|
@item ---show-policy-url
|
|
@itemx ---no-show-policy-url
|
|
Show policy URLs in the ---list-sigs or --check-sigs listings as well
|
|
as when verifying a signature with a policy URL in it. These options
|
|
are deprecated. Use `---list-options [no-]show-policy-url' and/or
|
|
`---verify-options [no-]show-policy-url' instead.
|
|
|
|
@item ---sig-keyserver-url @code{string}
|
|
Use @code{string} as a preferred keyserver URL for data signatures. If
|
|
you prefix it with an exclamation mark, the keyserver URL packet will
|
|
be flagged as critical.
|
|
|
|
The same %-expandos used for notation data are available here as well.
|
|
|
|
@item ---set-filename @code{string}
|
|
Use @code{string} as the filename which is stored inside messages.
|
|
This overrides the default, which is to use the actual filename of the
|
|
file being encrypted.
|
|
|
|
@item ---for-your-eyes-only
|
|
@itemx ---no-for-your-eyes-only
|
|
Set the `for your eyes only' flag in the message. This causes GnuPG
|
|
to refuse to save the file unless the ---output option is given, and
|
|
PGP to use the "secure viewer" with a Tempest-resistant font to
|
|
display the message. This option overrides ---set-filename.
|
|
---no-for-your-eyes-only disables this option.
|
|
|
|
@item ---use-embedded-filename
|
|
Try to create a file with a name as embedded in the data.
|
|
This can be a dangerous option as it allows to overwrite files.
|
|
|
|
@item ---completes-needed @code{n}
|
|
Number of completely trusted users to introduce a new
|
|
key signer (defaults to 1).
|
|
|
|
@item ---marginals-needed @code{n}
|
|
Number of marginally trusted users to introduce a new
|
|
key signer (defaults to 3)
|
|
|
|
@item ---max-cert-depth @code{n}
|
|
Maximum depth of a certification chain (default is 5).
|
|
|
|
@item ---cipher-algo @code{name}
|
|
Use @code{name} as cipher algorithm. Running the program
|
|
with the command ---version yields a list of supported
|
|
algorithms. If this is not used the cipher algorithm is
|
|
selected from the preferences stored with the key.
|
|
|
|
@item ---digest-algo @code{name}
|
|
Use @code{name} as the message digest algorithm. Running the program
|
|
with the command ---version yields a list of supported algorithms.
|
|
|
|
@item ---compress-algo @code{name}
|
|
Use compression algorithm @code{name}. "zlib" is RFC1950 ZLIB
|
|
compression. "zip" is RFC-1951 ZIP compression which is used by PGP.
|
|
"uncompressed" or "none" disables compression. If this option is not
|
|
used, the default behavior is to examine the recipient key preferences
|
|
to see which algorithms the recipient supports. If all else fails,
|
|
ZIP is used for maximum compatibility. Note, however, that ZLIB may
|
|
give better compression results if that is more important, as the
|
|
compression window size is not limited to 8k.
|
|
|
|
@item ---cert-digest-algo @code{name}
|
|
Use @code{name} as the message digest algorithm used when signing a
|
|
key. Running the program with the command ---version yields a list of
|
|
supported algorithms. Be aware that if you choose an algorithm that
|
|
GnuPG supports but other OpenPGP implementations do not, then some
|
|
users will not be able to use the key signatures you make, or quite
|
|
possibly your entire key.
|
|
|
|
@item ---s2k-cipher-algo @code{name}
|
|
Use @code{name} as the cipher algorithm used to protect secret keys.
|
|
The default cipher is CAST5. This cipher is also used for
|
|
conventional encryption if ---personal-cipher-preferences and
|
|
---cipher-algo is not given.
|
|
|
|
@item ---s2k-digest-algo @code{name}
|
|
Use @code{name} as the digest algorithm used to mangle the passphrases.
|
|
The default algorithm is SHA-1.
|
|
|
|
@item ---s2k-mode @code{n}
|
|
Selects how passphrases are mangled. If @code{n} is 0 a plain
|
|
passphrase (which is not recommended) will be used, a 1 adds a salt to
|
|
the passphrase and a 3 (the default) iterates the whole process a
|
|
couple of times. Unless ---rfc1991 is used, this mode is also used for
|
|
conventional encryption.
|
|
|
|
@item ---simple-sk-checksum
|
|
Secret keys are integrity protected by using a SHA-1 checksum. This
|
|
method will be part of an enhanced OpenPGP specification but GnuPG
|
|
already uses it as a countermeasure against certain attacks. Old
|
|
applications don't understand this new format, so this option may be
|
|
used to switch back to the old behaviour. Using this this option
|
|
bears a security risk. Note that using this option only takes effect
|
|
when the secret key is encrypted - the simplest way to make this
|
|
happen is to change the passphrase on the key (even changing it to the
|
|
same value is acceptable).
|
|
|
|
@item ---disable-cipher-algo @code{name}
|
|
Never allow the use of @code{name} as cipher algorithm.
|
|
The given name will not be checked so that a later loaded algorithm
|
|
will still get disabled.
|
|
|
|
@item ---disable-pubkey-algo @code{name}
|
|
Never allow the use of @code{name} as public key algorithm.
|
|
The given name will not be checked so that a later loaded algorithm
|
|
will still get disabled.
|
|
|
|
@item ---no-sig-cache
|
|
Do not cache the verification status of key signatures.
|
|
Caching gives a much better performance in key listings. However, if
|
|
you suspect that your public keyring is not save against write
|
|
modifications, you can use this option to disable the caching. It
|
|
probably does not make sense to disable it because all kind of damage
|
|
can be done if someone else has write access to your public keyring.
|
|
|
|
@item ---no-sig-create-check
|
|
GnuPG normally verifies each signature right after creation to protect
|
|
against bugs and hardware malfunctions which could leak out bits from
|
|
the secret key. This extra verification needs some time (about 115%
|
|
for DSA keys), and so this option can be used to disable it.
|
|
However, due to the fact that the signature creation needs manual
|
|
interaction, this performance penalty does not matter in most settings.
|
|
|
|
@item ---auto-check-trustdb
|
|
@itemx ---no-auto-check-trustdb
|
|
If GnuPG feels that its information about the Web-of-Trust has to be
|
|
updated, it automatically runs the ---check-trustdb command internally.
|
|
This may be a time consuming process. ---no-auto-check-trustdb
|
|
disables this option.
|
|
|
|
@item ---throw-keyid
|
|
Do not put the keyids into encrypted packets. This option hides the
|
|
receiver of the message and is a countermeasure against traffic
|
|
analysis. It may slow down the decryption process because all
|
|
available secret keys are tried.
|
|
|
|
@item ---no-throw-keyid
|
|
Resets the ---throw-keyid option.
|
|
|
|
@item ---not-dash-escaped
|
|
This option changes the behavior of cleartext signatures
|
|
so that they can be used for patch files. You should not
|
|
send such an armored file via email because all spaces
|
|
and line endings are hashed too. You can not use this
|
|
option for data which has 5 dashes at the beginning of a
|
|
line, patch files don't have this. A special armor header
|
|
line tells GnuPG about this cleartext signature option.
|
|
|
|
@item ---escape-from-lines
|
|
@itemx ---no-escape-from-lines
|
|
Because some mailers change lines starting with "From " to ">From
|
|
" it is good to handle such lines in a special way when creating
|
|
cleartext signatures to prevent the mail system from breaking the
|
|
signature. Note that all other PGP versions do it this way too.
|
|
Enabled by default. ---no-escape-from-lines disables this option.
|
|
|
|
@item ---passphrase-fd @code{n}
|
|
Read the passphrase from file descriptor @code{n}. If you use
|
|
0 for @code{n}, the passphrase will be read from stdin. This
|
|
can only be used if only one passphrase is supplied.
|
|
Don't use this option if you can avoid it.
|
|
|
|
@item ---command-fd @code{n}
|
|
This is a replacement for the deprecated shared-memory IPC mode.
|
|
If this option is enabled, user input on questions is not expected
|
|
from the TTY but from the given file descriptor. It should be used
|
|
together with ---status-fd. See the file doc/DETAILS in the source
|
|
distribution for details on how to use it.
|
|
|
|
@item ---use-agent
|
|
@itemx ---no-use-agent
|
|
Try to use the GnuPG-Agent. Please note that this agent is still under
|
|
development. With this option, GnuPG first tries to connect to the
|
|
agent before it asks for a passphrase. ---no-use-agent disables this
|
|
option.
|
|
|
|
@item ---gpg-agent-info
|
|
Override the value of the environment variable
|
|
@samp{GPG_AGENT_INFO}. This is only used when ---use-agent has been given
|
|
|
|
@item Compliance options
|
|
These options control what GnuPG is compliant to. Only one of these
|
|
options may be active at a time. Note that the default setting of
|
|
this is nearly always the correct one. See the INTEROPERABILITY WITH
|
|
OTHER OPENPGP PROGRAMS section below before using one of these
|
|
options.
|
|
|
|
@table @asis
|
|
@item ---gnupg
|
|
Use standard GnuPG behavior. This is essentially OpenPGP behavior
|
|
(see ---openpgp), but with some additional workarounds for common
|
|
compatibility problems in different versions of PGP. This is the
|
|
default option, so it is not generally needed, but it may be useful to
|
|
override a different compliance option in the gpg.conf file.
|
|
|
|
@item ---openpgp
|
|
Reset all packet, cipher and digest options to strict OpenPGP
|
|
behavior. Use this option to reset all previous options like
|
|
---rfc1991, --force-v3-sigs, --s2k-*, --cipher-algo, --digest-algo and
|
|
---compress-algo to OpenPGP compliant values. All PGP workarounds are
|
|
disabled.
|
|
|
|
@item ---rfc2440
|
|
Reset all packet, cipher and digest options to strict RFC-2440
|
|
behavior. Note that this is currently the same thing as ---openpgp.
|
|
|
|
@item ---rfc1991
|
|
Try to be more RFC-1991 (PGP 2.x) compliant.
|
|
|
|
@item ---pgp2
|
|
Set up all options to be as PGP 2.x compliant as possible, and warn if
|
|
an action is taken (e.g. encrypting to a non-RSA key) that will create
|
|
a message that PGP 2.x will not be able to handle. Note that `PGP
|
|
2.x' here means `MIT PGP 2.6.2'. There are other versions of PGP 2.x
|
|
available, but the MIT release is a good common baseline.
|
|
|
|
This option implies `---rfc1991 --disable-mdc --no-force-v4-certs
|
|
---no-sk-comment --escape-from-lines --force-v3-sigs
|
|
---no-ask-sig-expire --no-ask-cert-expire --cipher-algo IDEA
|
|
---digest-algo MD5 --compress-algo 1'. It also disables --textmode
|
|
when encrypting.
|
|
|
|
@item ---pgp6
|
|
Set up all options to be as PGP 6 compliant as possible. This
|
|
restricts you to the ciphers IDEA (if the IDEA plugin is installed),
|
|
3DES, and CAST5, the hashes MD5, SHA1 and RIPEMD160, and the
|
|
compression algorithms none and ZIP. This also disables
|
|
---throw-keyid, and making signatures with signing subkeys as PGP 6
|
|
does not understand signatures made by signing subkeys.
|
|
|
|
This option implies `---disable-mdc --no-sk-comment --escape-from-lines
|
|
---force-v3-sigs --no-ask-sig-expire'
|
|
|
|
@item ---pgp7
|
|
Set up all options to be as PGP 7 compliant as possible. This is
|
|
identical to ---pgp6 except that MDCs are not disabled, and the list of
|
|
allowable ciphers is expanded to add AES128, AES192, AES256, and
|
|
TWOFISH.
|
|
|
|
@item ---pgp8
|
|
Set up all options to be as PGP 8 compliant as possible. PGP 8 is a
|
|
lot closer to the OpenPGP standard than previous versions of PGP, so
|
|
all this does is disable ---throw-keyid and set --escape-from-lines.
|
|
The allowed algorithms list is the same as ---pgp7 with the addition of
|
|
the SHA-256 digest algorithm.
|
|
|
|
@end table
|
|
|
|
@item ---force-v3-sigs
|
|
@itemx ---no-force-v3-sigs
|
|
OpenPGP states that an implementation should generate v4 signatures
|
|
but PGP versions 5 and higher only recognize v4 signatures on key
|
|
material. This option forces v3 signatures for signatures on data.
|
|
Note that this option overrides ---ask-sig-expire, as v3 signatures
|
|
cannot have expiration dates. ---no-force-v3-sigs disables this
|
|
option.
|
|
|
|
@item ---force-v4-certs
|
|
@itemx ---no-force-v4-certs
|
|
Always use v4 key signatures even on v3 keys. This option also
|
|
changes the default hash algorithm for v3 RSA keys from MD5 to SHA-1.
|
|
---no-force-v4-certs disables this option.
|
|
|
|
@item ---force-mdc
|
|
Force the use of encryption with a modification detection code. This
|
|
is always used with the newer ciphers (those with a blocksize greater
|
|
than 64 bits), or if all of the recipient keys indicate MDC support in
|
|
their feature flags.
|
|
|
|
@item ---disable-mdc
|
|
Disable the use of the modification detection code. Note that by
|
|
using this option, the encrypted message becomes vulnerable to a
|
|
message modification attack.
|
|
|
|
@item ---allow-non-selfsigned-uid
|
|
@itemx ---no-allow-non-selfsigned-uid
|
|
Allow the import and use of keys with user IDs which are not
|
|
self-signed. This is not recommended, as a non self-signed user ID is
|
|
trivial to forge. ---no-allow-non-selfsigned-uid disables.
|
|
|
|
@item ---allow-freeform-uid
|
|
Disable all checks on the form of the user ID while generating a new
|
|
one. This option should only be used in very special environments as
|
|
it does not ensure the de-facto standard format of user IDs.
|
|
|
|
@item ---ignore-time-conflict
|
|
GnuPG normally checks that the timestamps associated with keys and
|
|
signatures have plausible values. However, sometimes a signature
|
|
seems to be older than the key due to clock problems. This option
|
|
makes these checks just a warning. See also ---ignore-valid-from for
|
|
timestamp issues on subkeys.
|
|
|
|
@item ---ignore-valid-from
|
|
GnuPG normally does not select and use subkeys created in the future.
|
|
This option allows the use of such keys and thus exhibits the
|
|
pre-1.0.7 behaviour. You should not use this option unless you there
|
|
is some clock problem. See also ---ignore-time-conflict for timestamp
|
|
issues with signatures.
|
|
|
|
@item ---ignore-crc-error
|
|
The ASCII armor used by OpenPGP is protected by a CRC checksum against
|
|
transmission errors. Sometimes it happens that the CRC gets mangled
|
|
somewhere on the transmission channel but the actual content (which is
|
|
protected by the OpenPGP protocol anyway) is still okay. This option
|
|
will let gpg ignore CRC errors.
|
|
|
|
@item ---ignore-mdc-error
|
|
This option changes a MDC integrity protection failure into a warning.
|
|
This can be useful if a message is partially corrupt, but it is
|
|
necessary to get as much data as possible out of the corrupt message.
|
|
However, be aware that a MDC protection failure may also mean that the
|
|
message was tampered with intentionally by an attacker.
|
|
|
|
@item ---lock-once
|
|
Lock the databases the first time a lock is requested
|
|
and do not release the lock until the process
|
|
terminates.
|
|
|
|
@item ---lock-multiple
|
|
Release the locks every time a lock is no longer
|
|
needed. Use this to override a previous ---lock-once
|
|
from a config file.
|
|
|
|
@item ---lock-never
|
|
Disable locking entirely. This option should be used only in very
|
|
special environments, where it can be assured that only one process
|
|
is accessing those files. A bootable floppy with a stand-alone
|
|
encryption system will probably use this. Improper usage of this
|
|
option may lead to data and key corruption.
|
|
|
|
@item ---no-random-seed-file
|
|
GnuPG uses a file to store its internal random pool over invocations.
|
|
This makes random generation faster; however sometimes write operations
|
|
are not desired. This option can be used to achieve that with the cost of
|
|
slower random generation.
|
|
|
|
@item ---no-verbose
|
|
Reset verbose level to 0.
|
|
|
|
@item ---no-greeting
|
|
Suppress the initial copyright message.
|
|
|
|
@item ---no-secmem-warning
|
|
Suppress the warning about "using insecure memory".
|
|
|
|
@item ---no-permission-warning
|
|
Suppress the warning about unsafe file and home directory (---homedir)
|
|
permissions. Note that the permission checks that GnuPG performs are
|
|
not intended to be authoritative, but rather they simply warn about
|
|
certain common permission problems. Do not assume that the lack of a
|
|
warning means that your system is secure.
|
|
|
|
Note that the warning for unsafe ---homedir permissions cannot be
|
|
supressed in the gpg.conf file, as this would allow an attacker to
|
|
place an unsafe gpg.conf file in place, and use this file to supress
|
|
warnings about itself. The ---homedir permissions warning may only be
|
|
supressed on the command line.
|
|
|
|
@item ---no-mdc-warning
|
|
Suppress the warning about missing MDC integrity protection.
|
|
|
|
@item ---no-armor
|
|
Assume the input data is not in ASCII armored format.
|
|
|
|
@item ---no-default-keyring
|
|
Do not add the default keyrings to the list of
|
|
keyrings.
|
|
|
|
@item ---skip-verify
|
|
Skip the signature verification step. This may be
|
|
used to make the decryption faster if the signature
|
|
verification is not needed.
|
|
|
|
@item ---with-colons
|
|
Print key listings delimited by colons. Note that the output will be
|
|
encoded in UTF-8 regardless of any ---charset setting. This format is
|
|
useful when GnuPG is called from scripts and other programs as it is
|
|
easily machine parsed. The details of this format are documented in
|
|
the file doc/DETAILS, which is included in the GnuPG source
|
|
distribution.
|
|
|
|
@item ---with-key-data
|
|
Print key listings delimited by colons (like ---with-colons) and print the public key data.
|
|
|
|
@item ---with-fingerprint
|
|
Same as the command ---fingerprint but changes only the format of the output
|
|
and may be used together with another command.
|
|
|
|
@item ---fast-list-mode
|
|
Changes the output of the list commands to work faster; this is achieved
|
|
by leaving some parts empty. Some applications don't need the user ID and
|
|
the trust information given in the listings. By using this options they
|
|
can get a faster listing. The exact behaviour of this option may change
|
|
in future versions.
|
|
|
|
@item ---fixed-list-mode
|
|
Do not merge primary user ID and primary key in ---with-colon listing
|
|
mode and print all timestamps as seconds since 1970-01-01.
|
|
|
|
@item ---list-only
|
|
Changes the behaviour of some commands. This is like ---dry-run but
|
|
different in some cases. The semantic of this command may be extended in
|
|
the future. Currently it only skips the actual decryption pass and
|
|
therefore enables a fast listing of the encryption keys.
|
|
|
|
@item ---no-literal
|
|
This is not for normal use. Use the source to see for what it might be useful.
|
|
|
|
@item ---set-filesize
|
|
This is not for normal use. Use the source to see for what it might be useful.
|
|
|
|
@item ---emulate-md-encode-bug
|
|
GnuPG versions prior to 1.0.2 had a bug in the way a signature was encoded.
|
|
This options enables a workaround by checking faulty signatures again with
|
|
the encoding used in old versions. This may only happen for ElGamal signatures
|
|
which are not widely used.
|
|
|
|
@item ---show-session-key
|
|
Display the session key used for one message. See ---override-session-key
|
|
for the counterpart of this option.
|
|
|
|
We think that Key-Escrow is a Bad Thing; however the user should
|
|
have the freedom to decide whether to go to prison or to reveal the content of
|
|
one specific message without compromising all messages ever encrypted for one
|
|
secret key. DON'T USE IT UNLESS YOU ARE REALLY FORCED TO DO SO.
|
|
|
|
@item ---override-session-key @code{string}
|
|
Don't use the public key but the session key @code{string}. The format of this
|
|
string is the same as the one printed by ---show-session-key. This option
|
|
is normally not used but comes handy in case someone forces you to reveal the
|
|
content of an encrypted message; using this option you can do this without
|
|
handing out the secret key.
|
|
|
|
@item ---ask-sig-expire
|
|
@itemx ---no-ask-sig-expire
|
|
When making a data signature, prompt for an expiration time. If this
|
|
option is not specified, the expiration time is "never".
|
|
---no-ask-sig-expire disables this option.
|
|
|
|
@item ---ask-cert-expire
|
|
@itemx ---no-ask-cert-expire
|
|
When making a key signature, prompt for an expiration time. If this
|
|
option is not specified, the expiration time is "never".
|
|
---no-ask-cert-expire disables this option.
|
|
|
|
@item ---expert
|
|
@itemx ---no-expert
|
|
Allow the user to do certain nonsensical or "silly" things like
|
|
signing an expired or revoked key, or certain potentially incompatible
|
|
things like generating deprecated key types. This also disables
|
|
certain warning messages about potentially incompatible actions. As
|
|
the name implies, this option is for experts only. If you don't fully
|
|
understand the implications of what it allows you to do, leave this
|
|
off. ---no-expert disables this option.
|
|
|
|
@item ---merge-only
|
|
Don't insert new keys into the keyrings while doing an import.
|
|
|
|
@item ---allow-secret-key-import
|
|
This is an obsolete option and is not used anywhere.
|
|
|
|
@item ---try-all-secrets
|
|
Don't look at the key ID as stored in the message but try all secret keys in
|
|
turn to find the right decryption key. This option forces the behaviour as
|
|
used by anonymous recipients (created by using ---throw-keyid) and might come
|
|
handy in case where an encrypted message contains a bogus key ID.
|
|
|
|
@item ---enable-special-filenames
|
|
This options enables a mode in which filenames of the form
|
|
@file{-&n}, where n is a non-negative decimal number,
|
|
refer to the file descriptor n and not to a file with that name.
|
|
|
|
@item ---no-expensive-trust-checks
|
|
Experimental use only.
|
|
|
|
@item ---group @code{name=value1 value2 value3 ...}
|
|
Sets up a named group, which is similar to aliases in email programs.
|
|
Any time the group name is a recipient (-r or ---recipient), it will
|
|
be expanded to the values specified.
|
|
|
|
The values are @code{key IDs} or fingerprints, but any key description
|
|
is accepted. Note that a value with spaces in it will be treated as
|
|
two different values. Note also there is only one level of expansion
|
|
- you cannot make an group that points to another group. When used
|
|
from the command line, it may be necessary to quote the argument to
|
|
this option to prevent the shell from treating it as multiple
|
|
arguments.
|
|
|
|
@item ---no-groups
|
|
Clear the ---group list.
|
|
|
|
@item ---preserve-permissions
|
|
Don't change the permissions of a secret keyring back to user
|
|
read/write only. Use this option only if you really know what you are doing.
|
|
|
|
@item ---personal-cipher-preferences @code{string}
|
|
Set the list of personal cipher preferences to @code{string}, this list
|
|
should be a string similar to the one printed by the command "pref" in
|
|
the edit menu. This allows the user to factor in their own preferred
|
|
algorithms when algorithms are chosen via recipient key preferences.
|
|
The most highly ranked cipher in this list is also used for the
|
|
---symmetric encryption command.
|
|
|
|
@item ---personal-digest-preferences @code{string}
|
|
Set the list of personal digest preferences to @code{string}, this list
|
|
should be a string similar to the one printed by the command "pref" in
|
|
the edit menu. This allows the user to factor in their own preferred
|
|
algorithms when algorithms are chosen via recipient key preferences.
|
|
The most highly ranked digest algorithm in this list is algo used when
|
|
signing without encryption (e.g. ---clearsign or --sign). The default
|
|
value is SHA-1.
|
|
|
|
@item ---personal-compress-preferences @code{string}
|
|
Set the list of personal compression preferences to @code{string}, this
|
|
list should be a string similar to the one printed by the command
|
|
"pref" in the edit menu. This allows the user to factor in their own
|
|
preferred algorithms when algorithms are chosen via recipient key
|
|
preferences. The most highly ranked algorithm in this list is also
|
|
used when there are no recipient keys to consider (e.g. ---symmetric).
|
|
|
|
@item ---default-preference-list @code{string}
|
|
Set the list of default preferences to @code{string}, this list should
|
|
be a string similar to the one printed by the command "pref" in the
|
|
edit menu. This affects both key generation and "updpref" in the edit
|
|
menu.
|
|
|
|
@end table
|
|
|
|
@majorheading How to specify a user ID
|
|
There are different ways to specify a user ID to GnuPG; here are some
|
|
examples:
|
|
|
|
@table @asis
|
|
@item
|
|
@item 234567C4
|
|
@itemx 0F34E556E
|
|
@itemx 01347A56A
|
|
@itemx 0xAB123456
|
|
Here the key ID is given in the usual short form.
|
|
|
|
@item 234AABBCC34567C4
|
|
@itemx 0F323456784E56EAB
|
|
@itemx 01AB3FED1347A5612
|
|
@itemx 0x234AABBCC34567C4
|
|
Here the key ID is given in the long form as used by OpenPGP
|
|
(you can get the long key ID using the option ---with-colons).
|
|
|
|
@item 1234343434343434C434343434343434
|
|
@itemx 123434343434343C3434343434343734349A3434
|
|
@itemx 0E12343434343434343434EAB3484343434343434
|
|
@itemx 0xE12343434343434343434EAB3484343434343434
|
|
The best way to specify a key ID is by using the fingerprint of
|
|
the key. This avoids any ambiguities in case that there are duplicated
|
|
key IDs (which are really rare for the long key IDs).
|
|
|
|
@item =Heinrich Heine <heinrichh@@uni-duesseldorf.de>
|
|
Using an exact to match string. The equal sign indicates this.
|
|
|
|
@item <heinrichh@@uni-duesseldorf.de>
|
|
Using the email address part which must match exactly. The left angle bracket
|
|
indicates this email address mode.
|
|
|
|
@item +Heinrich Heine duesseldorf
|
|
All words must match exactly (not case sensitive) but can appear in
|
|
any order in the user ID. Words are any sequences of letters,
|
|
digits, the underscore and all characters with bit 7 set.
|
|
|
|
@item Heine
|
|
@itemx *Heine
|
|
By case insensitive substring matching. This is the default mode but
|
|
applications may want to explicitly indicate this by putting the asterisk
|
|
in front.
|
|
|
|
@end table
|
|
|
|
Note that you can append an exclamation mark to key IDs or
|
|
fingerprints. This flag tells GnuPG to use exactly the given primary
|
|
or secondary key and not to try to figure out which secondary or
|
|
primary key to use.
|
|
|
|
@majorheading RETURN VALUE
|
|
The program returns 0 if everything was fine, 1 if at least
|
|
a signature was bad, and other error codes for fatal errors.
|
|
|
|
@majorheading EXAMPLES
|
|
@table @asis
|
|
@item gpg -se -r @code{Bob} @code{file}
|
|
sign and encrypt for user Bob
|
|
|
|
@item gpg ---clearsign @code{file}
|
|
make a clear text signature
|
|
|
|
@item gpg -sb @code{file}
|
|
make a detached signature
|
|
|
|
@item gpg ---list-keys @code{user_ID}
|
|
show keys
|
|
|
|
@item gpg ---fingerprint @code{user_ID}
|
|
show fingerprint
|
|
|
|
@item gpg ---verify @code{pgpfile}
|
|
@itemx gpg ---verify @code{sigfile} @code{files}
|
|
Verify the signature of the file but do not output the data. The second form
|
|
is used for detached signatures, where @code{sigfile} is the detached
|
|
signature (either ASCII armored of binary) and @code{files} are the signed
|
|
data; if this is not given the name of the file holding the signed data is
|
|
constructed by cutting off the extension (".asc" or ".sig") of
|
|
@code{sigfile} or by asking the user for the filename.
|
|
|
|
@end table
|
|
|
|
@majorheading ENVIRONMENT
|
|
@table @asis
|
|
@item HOME
|
|
Used to locate the default home directory.
|
|
|
|
@item GNUPGHOME
|
|
If set directory used instead of "~/.gnupg".
|
|
|
|
@item GPG_AGENT_INFO
|
|
Used to locate the gpg-agent; only honored when
|
|
---use-agent is set. The value consists of 3 colon delimited fields:
|
|
The first is the path to the Unix Domain Socket, the second the PID of
|
|
the gpg-agent and the protocol version which should be set to 1. When
|
|
starting the gpg-agent as described in its documentation, this
|
|
variable is set to the correct value. The option ---gpg-agent-info can
|
|
be used to override it.
|
|
|
|
@item http_proxy
|
|
Only honored when the keyserver-option
|
|
honor-http-proxy is set.
|
|
|
|
@end table
|
|
|
|
@majorheading FILES
|
|
@table @asis
|
|
@item ~/.gnupg/secring.gpg
|
|
The secret keyring
|
|
|
|
@item ~/.gnupg/secring.gpg.lock
|
|
and the lock file
|
|
|
|
@item ~/.gnupg/pubring.gpg
|
|
The public keyring
|
|
|
|
@item ~/.gnupg/pubring.gpg.lock
|
|
and the lock file
|
|
|
|
@item ~/.gnupg/trustdb.gpg
|
|
The trust database
|
|
|
|
@item ~/.gnupg/trustdb.gpg.lock
|
|
and the lock file
|
|
|
|
@item ~/.gnupg/random_seed
|
|
used to preserve the internal random pool
|
|
|
|
@item ~/.gnupg/gpg.conf
|
|
Default configuration file
|
|
|
|
@item ~/.gnupg/options
|
|
Old style configuration file; only used when gpg.conf
|
|
is not found
|
|
|
|
@item /usr[/local]/share/gnupg/options.skel
|
|
Skeleton options file
|
|
|
|
@item /usr[/local]/lib/gnupg/
|
|
Default location for extensions
|
|
|
|
@end table
|
|
|
|
@majorheading WARNINGS
|
|
Use a *good* password for your user account and a *good* passphrase
|
|
to protect your secret key. This passphrase is the weakest part of the
|
|
whole system. Programs to do dictionary attacks on your secret keyring
|
|
are very easy to write and so you should protect your "~/.gnupg/"
|
|
directory very well.
|
|
|
|
Keep in mind that, if this program is used over a network (telnet), it
|
|
is *very* easy to spy out your passphrase!
|
|
|
|
If you are going to verify detached signatures, make sure that the
|
|
program knows about it; either be giving both filenames on the
|
|
command line or using @samp{-} to specify stdin.
|
|
|
|
@majorheading INTEROPERABILITY WITH OTHER OPENPGP PROGRAMS
|
|
GnuPG tries to be a very flexible implementation of the OpenPGP
|
|
standard. In particular, GnuPG implements many of the "optional"
|
|
parts of the standard, such as the RIPEMD/160 hash, and the ZLIB
|
|
compression algorithms. It is important to be aware that not all
|
|
OpenPGP programs implement these optional algorithms and that by
|
|
forcing their use via the ---cipher-algo, --digest-algo,
|
|
---cert-digest-algo, or --compress-algo options in GnuPG, it is
|
|
possible to create a perfectly valid OpenPGP message, but one that
|
|
cannot be read by the intended recipient.
|
|
|
|
For example, as of this writing, no version of official PGP supports
|
|
the BLOWFISH cipher algorithm. If you use it, no PGP user will be
|
|
able to decrypt your message. The same thing applies to the ZLIB
|
|
compression algorithm. By default, GnuPG uses the OpenPGP preferences
|
|
system that will always do the right thing and create messages that
|
|
are usable by all recipients, regardless of which OpenPGP program they
|
|
use. Only override this safe default if you know what you are doing.
|
|
|
|
If you absolutely must override the safe default, or if the
|
|
preferences on a given key are invalid for some reason, you are far
|
|
better off using the ---pgp2, --pgp6, --pgp7, or --pgp8 options. These
|
|
options are safe as they do not force any particular algorithms in
|
|
violation of OpenPGP, but rather reduce the available algorithms to a
|
|
"PGP-safe" list.
|
|
|
|
@majorheading BUGS
|
|
On many systems this program should be installed as setuid(root). This
|
|
is necessary to lock memory pages. Locking memory pages prevents the
|
|
operating system from writing memory pages to disk. If you get no
|
|
warning message about insecure memory your operating system supports
|
|
locking without being root. The program drops root privileges as soon
|
|
as locked memory is allocated.
|
|
|
|
@bye
|