~ubuntu-branches/ubuntu/hardy/gnupg/hardy-updates : revision 1.1.7

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.TH "gpg" "1"

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.SH "NAME"

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gpg \(em encryption and signing tool

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.SH "SYNOPSIS"

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.PP

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.nf

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\fBgpg\fR [\-\-homedir \fBname\fR] [\-\-options \fBfile\fR] [\fBoptions\fR] \fBcommand\fR [\fBargs\fR]

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.fi

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.SH "DESCRIPTION"

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.PP

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\fBgpg\fR is the main program for the GnuPG system.

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.PP

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This man page only lists the commands and options available. For more

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verbose documentation get the GNU Privacy Handbook (GPH) or one of the

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other documents at http://www.gnupg.org/documentation/ .

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.PP

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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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.SH "COMMANDS"

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.PP

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\fBgpg\fR may be run with no commands, in which case it will

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perform a reasonable action depending on the type of file it is given

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as input (an encrypted message is decrypted, a signature is verified,

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a file containing keys is listed).

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.PP

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\fBgpg\fR recognizes these commands:

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.IP "\-s, \-\-sign [\fBfile\fR]" 10

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Make a signature. This command may be combined with \-\-encrypt (for a

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signed and encrypted message), \-\-symmetric (for a signed and

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symmetrically encrypted message), or \-\-encrypt and \-\-symmetric

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together (for a signed message that may be decrypted via a secret key

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or a passphrase).

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.IP "\-\-clearsign [\fBfile\fR]" 10

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Make a clear text signature. The content in a clear text signature is

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readable without any special software. OpenPGP software is only

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needed to verify the signature. Clear text signatures may modify

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end-of-line whitespace for platform independence and are not intended

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to be reversible.

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.IP "\-b, \-\-detach-sign [\fBfile\fR]" 10

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Make a detached signature.

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.IP "\-e, \-\-encrypt [\fBfile\fR]" 10

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Encrypt data. This option may be combined with \-\-sign (for a signed

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and encrypted message), \-\-symmetric (for a message that may be

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decrypted via a secret key or a passphrase), or \-\-sign and \-\-symmetric

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together (for a signed message that may be decrypted via a secret key

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or a passphrase).

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.IP "\-c, \-\-symmetric [\fBfile\fR]" 10

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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. This option may be combined with \-\-sign (for a

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signed and symmetrically encrypted message), \-\-encrypt (for a message

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that may be decrypted via a secret key or a passphrase), or \-\-sign and

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\-\-encrypt together (for a signed message that may be decrypted via a

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secret key or a passphrase).

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.IP "\-\-store [\fBfile\fR]" 10

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Store only (make a simple RFC1991 packet).

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.IP "\-d, \-\-decrypt [\fBfile\fR]" 10

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Decrypt \fBfile\fR (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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.IP "\-\-verify [[\fBsigfile\fR] [\fBsigned-files\fR]]" 10

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Assume that \fBsigfile\fR 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 \fB-\fP 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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.IP "\-\-multifile" 10

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This modifies certain other commands to accept multiple files for

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processing on the command line or read from stdin with each filename

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on a separate line. This allows for many files to be processed at

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once. \-\-multifile may currently be used along with \-\-verify,

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\-\-encrypt, and \-\-decrypt. Note that `\-\-multifile \-\-verify' may not be

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used with detached signatures.

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.IP "\-\-verify-files [\fBfiles\fR]" 10

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Identical to `\-\-multifile \-\-verify'.

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.IP "\-\-encrypt-files [\fBfiles\fR]" 10

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Identical to `\-\-multifile \-\-encrypt'.

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.IP "\-\-decrypt-files [\fBfiles\fR]" 10

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Identical to `\-\-multifile \-\-decrypt'.

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.IP "\-\-list-keys [\fBnames\fR]" 10

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.IP "\-\-list-public-keys [\fBnames\fR]" 10

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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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.IP "" 10

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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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.IP "\-K, \-\-list-secret-keys [\fBnames\fR]" 10

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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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.IP "\-\-list-sigs [\fBnames\fR]" 10

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Same as \-\-list-keys, but the signatures are listed too.

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.IP "" 10

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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 \-\-ask-cert-level), "L" for a local or

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non-exportable signature (see \-\-lsign-key), "R" for a nonRevocable

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signature (see the \-\-edit-key command "nrsign"), "P" for a signature

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that contains a policy URL (see \-\-cert-policy-url), "N" for a

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signature that contains a notation (see \-\-cert-notation), "X" for an

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eXpired signature (see \-\-ask-cert-expire), and the numbers 1-9 or "T"

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for 10 and above to indicate trust signature levels (see the

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\-\-edit-key command "tsign").

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.IP "\-\-check-sigs [\fBnames\fR]" 10

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Same as \-\-list-sigs, but the signatures are verified.

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.IP "\-\-fingerprint [\fBnames\fR]" 10

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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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.IP "\-\-list-packets" 10

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List only the sequence of packets. This is mainly

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useful for debugging.

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.IP "\-\-gen-key" 10

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Generate a new key pair. This command is normally only used

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interactively.

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.IP "" 10

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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 \fBdoc/DETAILS\fP in the source distribution on how to use this.

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.IP "\-\-edit-key \fBname\fR" 10

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Present a menu which enables you to do all key

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related tasks:

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.RS

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.IP "sign" 10

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Make a signature on key of user \fBname\fR If the key is not yet

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signed by the default user (or the users given with \-u), the program

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displays the information of the key again, together with its

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fingerprint and asks whether it should be signed. This question is

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repeated for all users specified with

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\-u.

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.IP "lsign" 10

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Same as "sign" but the signature is marked as non-exportable and will

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therefore never be used by others. This may be used to make keys

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valid only in the local environment.

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.IP "nrsign" 10

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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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.IP "tsign" 10

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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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.RE

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.IP "" 10

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Note that "l" (for local / non-exportable), "nr" (for non-revocable,

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and "t" (for trust) may be freely mixed and prefixed to "sign" to

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create a signature of any type desired.

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.RS

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.IP "revsig" 10

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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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.IP "trust" 10

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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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.IP "disable" 10

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.IP "enable" 10

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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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.IP "adduid" 10

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Create an alternate user id.

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.IP "addphoto" 10

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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. Note that a very large JPEG will

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make for a very large key. Also note that some programs will display

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your JPEG unchanged (GnuPG), and some programs will scale it to fit in

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a dialog box (PGP).

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.IP "deluid" 10

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Delete a user id.

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.IP "delsig" 10

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Delete a signature.

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.IP "revuid" 10

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Revoke a user id.

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.IP "addkey" 10

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Add a subkey to this key.

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.IP "addcardkey" 10

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Generate a key on a card and add it

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to this key.

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.IP "keytocard" 10

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Transfer the selected secret key (or the primary key if no key has

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been selected) to a smartcard. The secret key in the keyring will be

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replaced by a stub if the key could be stored successfully on the card

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and you use the save command later. Only certain key types may be

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transferred to the card. A sub menu allows you to select on what card

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to store the key. Note that it is not possible to get that key back

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from the card \- if the card gets broken your secret key will be lost

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unless you have a backup somewhere.

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.IP "bkuptocard \fBfile\fR" 10

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Restore the given file to a card. This command

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may be used to restore a backup key (as generated during card

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initialization) to a new card. In almost all cases this will be the

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encryption key. You should use this command only

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with the corresponding public key and make sure that the file

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given as argument is indeed the backup to restore. You should

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then select 2 to restore as encryption key.

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You will first be asked to enter the passphrase of the backup key and

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then for the Admin PIN of the card.

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.IP "delkey" 10

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Remove a subkey.

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.IP "addrevoker [sensitive]" 10

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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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.IP "revkey" 10

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Revoke a subkey.

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.IP "expire" 10

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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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.IP "passwd" 10

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Change the passphrase of the secret key.

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.IP "primary" 10

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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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.IP "uid \fBn\fR" 10

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Toggle selection of user id with index \fBn\fR.

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Use 0 to deselect all.

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.IP "key \fBn\fR" 10

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Toggle selection of subkey with index \fBn\fR.

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Use 0 to deselect all.

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.IP "check" 10

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Check all selected user ids.

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.IP "showphoto" 10

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Display the selected photographic user

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id.

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.IP "pref" 10

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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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.IP "showpref" 10

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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 3DES

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(cipher), SHA-1 (digest), and Uncompressed (compression) if they are

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not already included in the preference list. In addition, the

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preferred keyserver and signature notations (if any) are shown.

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.IP "setpref \fBstring\fR" 10

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Set the list of user ID preferences to \fBstring\fR for all (or just

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the selected) user IDs. Calling setpref with no arguments sets the

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preference list to the default (either built-in or set via

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\-\-default-preference-list), and calling setpref with "none" as the

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argument sets an empty preference list. Use "gpg \-\-version" to get a

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list of available algorithms. Note that while you can change the

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preferences on an attribute user ID (aka "photo ID"), GnuPG does not

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select keys via attribute user IDs so these preferences will not be

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used by GnuPG.

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.IP "keyserver" 10

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Set a preferred keyserver for the specified user ID(s). This allows

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other users to know where you prefer they get your key from. See

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\-\-keyserver-options honor-keyserver-url for more on how this works.

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Setting a value of "none" removes an existing preferred keyserver.

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.IP "notation" 10

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Set a name=value notation for the specified user ID(s). See

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\-\-cert-notation for more on how this works. Setting a value of "none"

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removes all notations, setting a notation prefixed with a minus sign

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(\-) removes that notation, and setting a notation name (without the

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=value) prefixed with a minus sign removes all notations with that

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name.

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.IP "toggle" 10

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Toggle between public and secret key listing.

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.IP "clean" 10

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Compact (by removing all signatures except the selfsig) any user ID

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that is no longer usable (e.g. revoked, or expired). Then, remove any

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signatures that are not usable by the trust calculations.

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Specifically, this removes any signature that does not validate, any

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signature that is superseded by a later signature, revoked signatures,

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and signatures issued by keys that are not present on the keyring.

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.IP "minimize" 10

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Make the key as small as possible. This removes all signatures from

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each user ID except for the most recent self-signature.

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.IP "cross-certify" 10

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Add cross-certification signatures to signing subkeys that may not

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currently have them. Cross-certification signatures protect against a

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subtle attack against signing subkeys. See

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\-\-require-cross-certification.

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.IP "save" 10

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Save all changes to the key rings and quit.

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.IP "quit" 10

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Quit the program without updating the

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key rings.

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.RE

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.IP "" 10

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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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.RS

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.IP "\-" 10

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No ownertrust assigned / not yet calculated.

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.IP "e" 10

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Trust

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calculation has failed; probably due to an expired key.

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.IP "q" 10

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Not enough information for calculation.

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.IP "n" 10

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Never trust this key.

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.IP "m" 10

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Marginally trusted.

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.IP "f" 10

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Fully trusted.

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.IP "u" 10

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Ultimately trusted.

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.RE

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.IP "\-\-card-edit" 10

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Present a menu to work with a smartcard. The subcommand "help" provides

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an overview on available commands. For a detailed description, please

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see the Card HOWTO at

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http://www.gnupg.org/documentation/howtos.html#GnuPG-cardHOWTO .

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.IP "\-\-card-status" 10

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Show the content of the smart card.

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.IP "\-\-change-pin" 10

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Present a menu to allow changing the PIN of a smartcard. This

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functionality is also available as the subcommand "passwd" with the

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\-\-card-edit command.

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.IP "\-\-sign-key \fBname\fR" 10

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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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.IP "\-\-lsign-key \fBname\fR" 10

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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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.IP "\-\-delete-key \fBname\fR" 10

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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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.IP "\-\-delete-secret-key \fBname\fR" 10

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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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.IP "\-\-delete-secret-and-public-key \fBname\fR" 10

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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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.IP "\-\-gen-revoke \fBname\fR" 10

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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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.IP "\-\-desig-revoke \fBname\fR" 10

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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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.IP "\-\-export [\fBnames\fR]" 10

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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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.IP "\-\-send-keys [\fBnames\fR]" 10

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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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.IP "\-\-export-secret-keys [\fBnames\fR]" 10

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.IP "\-\-export-secret-subkeys [\fBnames\fR]" 10

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Same as \-\-export, but exports the secret keys instead.

381

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

383

render the secret part of the primary key useless; this is

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a GNU extension to OpenPGP and other implementations can

385

not be expected to successfully import such a key.

386

387

See the option \-\-simple-sk-checksum if you want to import such an

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exported key with an older OpenPGP implementation.

389

.IP "\-\-import [\fBfiles\fR]" 10

390

.IP "\-\-fast-import [\fBfiles\fR]" 10

391

Import/merge keys. This adds the given keys to the

392

keyring. The fast version is currently just a synonym.

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.IP "" 10

394

There are a few other options which control how this command works.

395

Most notable here is the \-\-keyserver-options merge-only option which

396

does not insert new keys but does only the merging of new signatures,

397

user-IDs and subkeys.

398

.IP "\-\-recv-keys \fBkey IDs\fR" 10

399

Import the keys with the given key IDs from a keyserver. Option

400

\-\-keyserver must be used to give the name of this keyserver.

401

.IP "\-\-refresh-keys [\fBkey IDs\fR]" 10

402

Request updates from a keyserver for keys that already exist on the

403

local keyring. This is useful for updating a key with the latest

404

signatures, user IDs, etc. Calling this with no arguments will

405

refresh the entire keyring. Option \-\-keyserver must be used to give

406

the name of the keyserver for all keys that do not have preferred

407

keyservers set (see \-\-keyserver-options honor-keyserver-url).

408

.IP "\-\-search-keys \fBnames\fR" 10

409

Search the keyserver for the given names. Multiple names given here

410

will be joined together to create the search string for the keyserver.

411

Option \-\-keyserver must be used to give the name of this keyserver.

412

Keyservers that support different search methods allow using the

413

syntax specified in "How to specify a user ID" below. Note that

414

different keyserver types support different search methods. Currently

415

only LDAP supports them all.

416

.IP "\-\-fetch-keys \fBURIs\fR" 10

417

Retrieve keys located at the specified URIs. Note that different

418

installations of GnuPG may support different protocols (HTTP, FTP,

419

LDAP, etc.)

420

.IP "\-\-update-trustdb" 10

421

Do trust database maintenance. This command iterates over all keys

422

and builds the Web of Trust. This is an interactive command because it

423

may have to ask for the "ownertrust" values for keys. The user has to

424

give an estimation of how far she trusts the owner of the displayed

425

key to correctly certify (sign) other keys. GnuPG only asks for the

426

ownertrust value if it has not yet been assigned to a key. Using the

427

\-\-edit-key menu, the assigned value can be changed at any time.

428

.IP "\-\-check-trustdb" 10

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Do trust database maintenance without user interaction. From time to

430

time the trust database must be updated so that expired keys or

431

signatures and the resulting changes in the Web of Trust can be

432

tracked. Normally, GnuPG will calculate when this is required and do

433

it automatically unless \-\-no-auto-check-trustdb is set. This command

434

can be used to force a trust database check at any time. The

435

processing is identical to that of \-\-update-trustdb but it skips keys

436

with a not yet defined "ownertrust".

437

.IP "" 10

438

For use with cron jobs, this command can be used together with \-\-batch

439

in which case the trust database check is done only if a check is

440

needed. To force a run even in batch mode add the option \-\-yes.

441

.IP "\-\-export-ownertrust" 10

442

Send the ownertrust values to stdout. This is useful for backup

443

purposes as these values are the only ones which can't be re-created

444

from a corrupted trust DB.

445

.IP "\-\-import-ownertrust [\fBfiles\fR]" 10

446

Update the trustdb with the ownertrust values stored

447

in \fBfiles\fR (or stdin if not given); existing

448

values will be overwritten.

449

.IP "\-\-rebuild-keydb-caches" 10

450

When updating from version 1.0.6 to 1.0.7 this command should be used

451

to create signature caches in the keyring. It might be handy in other

452

situations too.

453

.IP "\-\-print-md \fBalgo\fR [\fBfiles\fR]" 10

454

.IP "\-\-print-mds [\fBfiles\fR]" 10

455

Print message digest of algorithm ALGO for all given files or stdin.

456

With the second form (or a deprecated "*" as algo) digests for all

457

available algorithms are printed.

458

.IP "\-\-gen-random \fB0|1|2\fR [\fBcount\fR]" 10

459

Emit COUNT random bytes of the given quality level. If count is not given

460

or zero, an endless sequence of random bytes will be emitted.

461

PLEASE, don't use this command unless you know what you are doing; it may

462

remove precious entropy from the system!

463

.IP "\-\-gen-prime \fBmode\fR \fBbits\fR [\fBqbits\fR]" 10

464

Use the source, Luke :\-). The output format is still subject to change.

465

.IP "\-\-version" 10

466

Print version information along with a list

467

of supported algorithms.

468

.IP "\-\-warranty" 10

469

Print warranty information.

470

.IP "\-h, \-\-help" 10

471

Print usage information. This is a really long list even though it

472

doesn't list all options. For every option, consult this manual.

473

.SH "OPTIONS"

474

.PP

475

Long options can be put in an options file (default

476

"~/.gnupg/gpg.conf"). Short option names will not work \- for example,

477

"armor" is a valid option for the options file, while "a" is not. Do

478

not write the 2 dashes, but simply the name of the option and any

479

required arguments. Lines with a hash ('#') as the first

480

non-white-space character are ignored. Commands may be put in this

481

file too, but that is not generally useful as the command will execute

482

automatically with every execution of gpg.

483

.PP

484

\fBgpg\fR recognizes these options:

485

.IP "\-a, \-\-armor" 10

486

Create ASCII armored output.

487

.IP "\-o, \-\-output \fBfile\fR" 10

488

Write output to \fBfile\fR.

489

.IP "\-\-max-output \fBn\fR" 10

490

This option sets a limit on the number of bytes that will be generated

491

when processing a file. Since OpenPGP supports various levels of

492

compression, it is possible that the plaintext of a given message may

493

be significantly larger than the original OpenPGP message. While

494

GnuPG works properly with such messages, there is often a desire to

495

set a maximum file size that will be generated before processing is

496

forced to stop by the OS limits. Defaults to 0, which means "no

497

limit".

498

.IP "\-\-mangle-dos-filenames" 10

499

.IP "\-\-no-mangle-dos-filenames" 10

500

Older version of Windows cannot handle filenames with more than one

501

dot. \-\-mangle-dos-filenames causes GnuPG to replace (rather than add

502

to) the extension of an output filename to avoid this problem. This

503

option is off by default and has no effect on non-Windows platforms.

504

.IP "\-u, \-\-local-user \fBname\fR" 10

505

Use \fBname\fR as the key to sign with. Note that this option

506

overrides \-\-default-key.

507

.IP "\-\-default-key \fBname\fR" 10

508

Use \fBname\fR as the default key to sign with. If this option is not

509

used, the default key is the first key found in the secret keyring.

510

Note that \-u or \-\-local-user overrides this option.

511

.IP "\-r, \-\-recipient \fBname\fR" 10

512

Encrypt for user id \fBname\fR. If this option or \-\-hidden-recipient

513

is not specified, GnuPG asks for the user-id unless

514

\-\-default-recipient is given.

515

.IP "\-R, \-\-hidden-recipient \fBname\fR" 10

516

Encrypt for user ID \fBname\fR, but hide the key ID of this user's

517

key. This option helps to hide the receiver of the message and is a

518

limited countermeasure against traffic analysis. If this option or

519

\-\-recipient is not specified, GnuPG asks for the user ID unless

520

\-\-default-recipient is given.

521

.IP "\-\-default-recipient \fBname\fR" 10

522

Use \fBname\fR as default recipient if option \-\-recipient is not used and

523

don't ask if this is a valid one. \fBname\fR must be non-empty.

524

.IP "\-\-default-recipient-self" 10

525

Use the default key as default recipient if option \-\-recipient is not used and

526

don't ask if this is a valid one. The default key is the first one from the

527

secret keyring or the one set with \-\-default-key.

528

.IP "\-\-no-default-recipient" 10

529

Reset \-\-default-recipient and \-\-default-recipient-self.

530

.IP "\-\-encrypt-to \fBname\fR" 10

531

Same as \-\-recipient but this one is intended for use

532

in the options file and may be used with

533

your own user-id as an "encrypt-to-self". These keys

534

are only used when there are other recipients given

535

either by use of \-\-recipient or by the asked user id.

536

No trust checking is performed for these user ids and

537

even disabled keys can be used.

538

.IP "\-\-hidden-encrypt-to \fBname\fR" 10

539

Same as \-\-hidden-recipient but this one is intended for use in the

540

options file and may be used with your own user-id as a hidden

541

"encrypt-to-self". These keys are only used when there are other

542

recipients given either by use of \-\-recipient or by the asked user id.

543

No trust checking is performed for these user ids and even disabled

544

keys can be used.

545

.IP "\-\-no-encrypt-to" 10

546

Disable the use of all \-\-encrypt-to and \-\-hidden-encrypt-to keys.

547

.IP "\-v, \-\-verbose" 10

548

Give more information during processing. If used

549

twice, the input data is listed in detail.

550

.IP "\-q, \-\-quiet" 10

551

Try to be as quiet as possible.

552

.IP "\-z \fBn\fR" 10

553

.IP "\-\-compress-level \fBn\fR" 10

554

.IP "\-\-bzip2-compress-level \fBn\fR" 10

555

Set compression level to \fBn\fR for the ZIP and ZLIB compression

556

algorithms. The default is to use the default compression level of

557

zlib (normally 6). \-\-bzip2-compress-level sets the compression level

558

for the BZIP2 compression algorithm (defaulting to 6 as well). This

559

is a different option from \-\-compress-level since BZIP2 uses a

560

significant amount of memory for each additional compression level.

561

\-z sets both. A value of 0 for \fBn\fR disables compression.

562

.IP "\-\-bzip2-decompress-lowmem" 10

563

Use a different decompression method for BZIP2 compressed files. This

564

alternate method uses a bit more than half the memory, but also runs

565

at half the speed. This is useful under extreme low memory

566

circumstances when the file was originally compressed at a high

567

\-\-bzip2-compress-level.

568

.IP "\-t, \-\-textmode" 10

569

.IP "\-\-no-textmode" 10

570

Treat input files as text and store them in the OpenPGP canonical text

571

form with standard "CRLF" line endings. This also sets the necessary

572

flags to inform the recipient that the encrypted or signed data is

573

text and may need its line endings converted back to whatever the

574

local system uses. This option is useful when communicating between

575

two platforms that have different line ending conventions (UNIX-like

576

to Mac, Mac to Windows, etc). \-\-no-textmode disables this option, and

577

is the default.

578

.IP "" 10

579

If \-t (but not \-\-textmode) is used together with armoring and signing,

580

this enables clearsigned messages. This kludge is needed for

581

command-line compatibility with command-line versions of PGP; normally

582

you would use \-\-sign or \-\-clearsign to select the type of the

583

signature.

584

.IP "\-n, \-\-dry-run" 10

585

Don't make any changes (this is not completely implemented).

586

.IP "\-i, \-\-interactive" 10

587

Prompt before overwriting any files.

588

.IP "\-\-batch" 10

589

.IP "\-\-no-batch" 10

590

Use batch mode. Never ask, do not allow interactive commands.

591

\-\-no-batch disables this option.

592

.IP "\-\-no-tty" 10

593

Make sure that the TTY (terminal) is never used for any output.

594

This option is needed in some cases because GnuPG sometimes prints

595

warnings to the TTY if \-\-batch is used.

596

.IP "\-\-yes" 10

597

Assume "yes" on most questions.

598

.IP "\-\-no" 10

599

Assume "no" on most questions.

600

.IP "\-\-ask-cert-level" 10

601

.IP "\-\-no-ask-cert-level" 10

602

When making a key signature, prompt for a certification level. If

603

this option is not specified, the certification level used is set via

604

\-\-default-cert-level. See \-\-default-cert-level for information on the

605

specific levels and how they are used. \-\-no-ask-cert-level disables

606

this option. This option defaults to no.

607

.IP "\-\-default-cert-level \fBn\fR" 10

608

The default to use for the check level when signing a key.

609

.IP "" 10

610

0 means you make no particular claim as to how carefully you verified

611

the key.

612

.IP "" 10

613

1 means you believe the key is owned by the person who claims to own

614

it but you could not, or did not verify the key at all. This is

615

useful for a "persona" verification, where you sign the key of a

616

pseudonymous user.

617

.IP "" 10

618

2 means you did casual verification of the key. For example, this

619

could mean that you verified that the key fingerprint and checked the

620

user ID on the key against a photo ID.

621

.IP "" 10

622

3 means you did extensive verification of the key. For example, this

623

could mean that you verified the key fingerprint with the owner of the

624

key in person, and that you checked, by means of a hard to forge

625

document with a photo ID (such as a passport) that the name of the key

626

owner matches the name in the user ID on the key, and finally that you

627

verified (by exchange of email) that the email address on the key

628

belongs to the key owner.

629

.IP "" 10

630

Note that the examples given above for levels 2 and 3 are just that:

631

examples. In the end, it is up to you to decide just what "casual"

632

and "extensive" mean to you.

633

.IP "" 10

634

This option defaults to 0 (no particular claim).

635

.IP "\-\-min-cert-level" 10

636

When building the trust database, treat any signatures with a

637

certification level below this as invalid. Defaults to 2, which

638

disregards level 1 signatures. Note that level 0 "no particular

639

claim" signatures are always accepted.

640

.IP "\-\-trusted-key \fBlong key ID\fR" 10

641

Assume that the specified key (which must be given

642

as a full 8 byte key ID) is as trustworthy as one of

643

your own secret keys. This option is useful if you

644

don't want to keep your secret keys (or one of them)

645

online but still want to be able to check the validity of a given

646

recipient's or signator's key.

647

.IP "\-\-trust-model \fBpgp|classic|direct|always|auto\fR" 10

648

Set what trust model GnuPG should follow. The models are:

649

650

.RS

651

.IP "pgp" 10

652

This is the Web of Trust combined with trust signatures as used in PGP

653

5.x and later. This is the default trust model when creating a new

654

trust database.

655

.IP "classic" 10

656

This is the standard Web of Trust as used in PGP 2.x and earlier.

657

.IP "direct" 10

658

Key validity is set directly by the user and not calculated via the

659

Web of Trust.

660

.IP "always" 10

661

Skip key validation and assume that used keys are always fully

662

trusted. You generally won't use this unless you are using some

663

external validation scheme. This option also suppresses the

664

"[uncertain]" tag printed with signature checks when there is no

665

evidence that the user ID is bound to the key.

666

.IP "auto" 10

667

Select the trust model depending on whatever the internal trust

668

database says. This is the default model if such a database already

669

exists.

670

.RE

671

.IP "\-\-always-trust" 10

672

Identical to `\-\-trust-model always'. This option is deprecated.

673

.IP "\-\-auto-key-locate \fBparameters\fR" 10

674

.IP "\-\-no-auto-key-locate" 10

675

GnuPG can automatically locate and retrieve keys as needed using this

676

option. This happens when encrypting to an email address (in the

677

"user@example.com" form), and there are no user@example.com keys on

678

the local keyring. This option takes any number of the following

679

arguments, in the order they are to be tried:

680

681

.RS

682

.IP "cert" 10

683

locate a key using DNS CERT, as specified in 2538bis (currently in

684

draft): http://www.josefsson.org/rfc2538bis/

685

.IP "pka" 10

686

locate a key using DNS PKA.

687

.IP "ldap" 10

688

locate a key using the PGP Universal method of checking

689

"ldap://keys.(thedomain)".

690

.IP "keyserver" 10

691

locate a key using whatever keyserver is defined using the \-\-keyserver

692

option.

693

.IP "(keyserver URL)" 10

694

In addition, a keyserver URL as used in the \-\-keyserver option may be

695

used here to query that particular keyserver.

696

.RE

697

.IP "\-\-keyid-format \fBshort|0xshort|long|0xlong\fR" 10

698

Select how to display key IDs. "short" is the traditional 8-character

699

key ID. "long" is the more accurate (but less convenient)

700

16-character key ID. Add an "0x" to either to include an "0x" at the

701

beginning of the key ID, as in 0x99242560.

702

.IP "\-\-keyserver \fBname\fR [name=value1 value2 value3 ...]" 10

703

Use \fBname\fR as your keyserver. This is the server that

704

\-\-recv-keys, \-\-send-keys, and \-\-search-keys will communicate with to

705

receive keys from, send keys to, and search for keys on. The format

706

of the \fBname\fR is a URI: `scheme:[//]keyservername[:port]' The

707

scheme is the type of keyserver: "hkp" for the HTTP (or compatible)

708

keyservers, "ldap" for the LDAP keyservers, or "mailto" for the Graff

709

email keyserver. Note that your particular installation of GnuPG may

710

have other keyserver types available as well. Keyserver schemes are

711

case-insensitive. After the keyserver name, optional keyserver

712

configuration options may be provided. These are the same as the

713

global \-\-keyserver-options from below, but apply only to this

714

particular keyserver.

715

.IP "" 10

716

Most keyservers synchronize with each other, so there is generally no

717

need to send keys to more than one server. The keyserver

718

"hkp://subkeys.pgp.net" uses round robin DNS to give a different

719

keyserver each time you use it.

720

.IP "\-\-keyserver-options \fBname=value1 [value2 value3 ...]\fR" 10

721

This is a space or comma delimited string that gives options for the

722

keyserver. Options can be prepended with a `no-' to give the opposite

723

meaning. Valid import-options or export-options may be used here as

724

well to apply to importing (\-\-recv-key) or exporting (\-\-send-key) a

725

key from a keyserver. While not all options are available for all

726

keyserver types, some common options are:

727

.RS

728

.IP "include-revoked" 10

729

When searching for a key with \-\-search-keys, include keys that are

730

marked on the keyserver as revoked. Note that not all keyservers

731

differentiate between revoked and unrevoked keys, and for such

732

keyservers this option is meaningless. Note also that most keyservers

733

do not have cryptographic verification of key revocations, and so

734

turning this option off may result in skipping keys that are

735

incorrectly marked as revoked.

736

.IP "include-disabled" 10

737

When searching for a key with \-\-search-keys, include keys that are

738

marked on the keyserver as disabled. Note that this option is not

739

used with HKP keyservers.

740

.IP "auto-key-retrieve" 10

741

This option enables the automatic retrieving of keys from a keyserver

742

when verifying signatures made by keys that are not on the local

743

keyring.

744

.IP "" 10

745

Note that this option makes a "web bug" like behavior possible.

746

Keyserver operators can see which keys you request, so by sending you

747

a message signed by a brand new key (which you naturally will not have

748

on your local keyring), the operator can tell both your IP address and

749

the time when you verified the signature.

750

.IP "honor-keyserver-url" 10

751

When using \-\-refresh-keys, if the key in question has a preferred

752

keyserver URL, then use that preferred keyserver to refresh the key

753

from. In addition, if auto-key-retrieve is set, and the signature

754

being verified has a preferred keyserver URL, then use that preferred

755

keyserver to fetch the key from. Defaults to yes.

756

.IP "honor-pka-record" 10

757

If auto-key-retrieve is set, and the signature being verified has a

758

PKA record, then use the PKA information to fetch the key. Defaults

759

to yes.

760

.IP "include-subkeys" 10

761

When receiving a key, include subkeys as potential targets. Note that

762

this option is not used with HKP keyservers, as they do not support

763

retrieving keys by subkey id.

764

.IP "use-temp-files" 10

765

On most Unix-like platforms, GnuPG communicates with the keyserver

766

helper program via pipes, which is the most efficient method. This

767

option forces GnuPG to use temporary files to communicate. On some

768

platforms (such as Win32 and RISC OS), this option is always enabled.

769

.IP "keep-temp-files" 10

770

If using `use-temp-files', do not delete the temp files after using

771

them. This option is useful to learn the keyserver communication

772

protocol by reading the temporary files.

773

.IP "verbose" 10

774

Tell the keyserver helper program to be more verbose. This option can

775

be repeated multiple times to increase the verbosity level.

776

.IP "timeout[=value]" 10

777

Tell the keyserver helper program how long (in seconds) to try and

778

perform a keyserver action before giving up. Note that performing

779

multiple actions at the same time uses this timeout value per action.

780

For example, when retrieving multiple keys via \-\-recv-keys, the

781

timeout applies separately to each key retrieval, and not to the

782

\-\-recv-keys command as a whole. Defaults to 30 seconds.

783

.IP "http-proxy[=value]" 10

784

For HTTP-like keyserver schemes that (such as HKP and HTTP itself),

785

try to access the keyserver over a proxy. If a \fBvalue\fR is

786

specified, use this as the HTTP proxy. If no \fBvalue\fR is

787

specified, the value of the environment variable "http_proxy", if any,

788

will be used.

789

.IP "max-cert-size[=value]" 10

790

When retrieving a key via DNS CERT, only accept keys up to this size.

791

Defaults to 16384 bytes.

792

.RE

793

.IP "\-\-import-options \fBparameters\fR" 10

794

This is a space or comma delimited string that gives options for

795

importing keys. Options can be prepended with a `no-' to give the

796

opposite meaning. The options are:

797

.RS

798

.IP "import-local-sigs" 10

799

Allow importing key signatures marked as "local". This is not

800

generally useful unless a shared keyring scheme is being used.

801

Defaults to no.

802

.IP "repair-pks-subkey-bug" 10

803

During import, attempt to repair the damage caused by the PKS

804

keyserver bug (pre version 0.9.6) that mangles keys with multiple

805

subkeys. Note that this cannot completely repair the damaged key as

806

some crucial data is removed by the keyserver, but it does at least

807

give you back one subkey. Defaults to no for regular \-\-import and to

808

yes for keyserver \-\-recv-keys.

809

.IP "merge-only" 10

810

During import, allow key updates to existing keys, but do not allow

811

any new keys to be imported. Defaults to no.

812

.IP "import-clean" 10

813

After import, compact (remove all signatures except the

814

self-signature) any user IDs from the new key that are not usable.

815

Then, remove any signatures from the new key that are not usable.

816

This includes signatures that were issued by keys that are not present

817

on the keyring. This option is the same as running the \-\-edit-key

818

command "clean" after import. Defaults to no.

819

.IP "import-minimal" 10

820

Import the smallest key possible. This removes all signatures except

821

the most recent self-signature on each user ID. This option is the

822

same as running the \-\-edit-key command "minimize" after import.

823

Defaults to no.

824

.RE

825

.IP "\-\-export-options \fBparameters\fR" 10

826

This is a space or comma delimited string that gives options for

827

exporting keys. Options can be prepended with a `no-' to give the

828

opposite meaning. The options are:

829

.RS

830

.IP "export-local-sigs" 10

831

Allow exporting key signatures marked as "local". This is not

832

generally useful unless a shared keyring scheme is being used.

833

Defaults to no.

834

.IP "export-attributes" 10

835

Include attribute user IDs (photo IDs) while exporting. This is

836

useful to export keys if they are going to be used by an OpenPGP

837

program that does not accept attribute user IDs. Defaults to yes.

838

.IP "export-sensitive-revkeys" 10

839

Include designated revoker information that was marked as

840

"sensitive". Defaults to no.

841

.IP "export-reset-subkey-passwd" 10

842

When using the "\-\-export-secret-subkeys" command, this option resets

843

the passphrases for all exported subkeys to empty. This is useful

844

when the exported subkey is to be used on an unattended machine where

845

a passphrase doesn't necessarily make sense. Defaults to no.

846

.IP "export-clean" 10

847

Compact (remove all signatures from) user IDs on the key being

848

exported if the user IDs are not usable. Also, do not export any

849

signatures that are not usable. This includes signatures that were

850

issued by keys that are not present on the keyring. This option is

851

the same as running the \-\-edit-key command "clean" before export

852

except that the local copy of the key is not modified. Defaults to

853

no.

854

.IP "export-minimal" 10

855

Export the smallest key possible. This removes all signatures except

856

the most recent self-signature on each user ID. This option is the

857

same as running the \-\-edit-key command "minimize" before export except

858

that the local copy of the key is not modified. Defaults to no.

859

.RE

860

.IP "\-\-list-options \fBparameters\fR" 10

861

This is a space or comma delimited string that gives options used when

862

listing keys and signatures (that is, \-\-list-keys, \-\-list-sigs,

863

\-\-list-public-keys, \-\-list-secret-keys, and the \-\-edit-key functions).

864

Options can be prepended with a `no-' to give the opposite meaning.

865

The options are:

866

.RS

867

.IP "show-photos" 10

868

Causes \-\-list-keys, \-\-list-sigs, \-\-list-public-keys, and

869

\-\-list-secret-keys to display any photo IDs attached to the key.

870

Defaults to no. See also \-\-photo-viewer.

871

.IP "show-policy-urls" 10

872

Show policy URLs in the \-\-list-sigs or \-\-check-sigs listings.

873

Defaults to no.

874

.IP "show-notations" 10

875

.IP "show-std-notations" 10

876

.IP "show-user-notations" 10

877

Show all, IETF standard, or user-defined signature notations in the

878

\-\-list-sigs or \-\-check-sigs listings. Defaults to no.

879

.IP "show-keyserver-urls" 10

880

Show any preferred keyserver URL in the \-\-list-sigs or \-\-check-sigs

881

listings. Defaults to no.

882

.IP "show-uid-validity" 10

883

Display the calculated validity of user IDs during key listings.

884

Defaults to no.

885

.IP "show-unusable-uids" 10

886

Show revoked and expired user IDs in key listings. Defaults to no.

887

.IP "show-unusable-subkeys" 10

888

Show revoked and expired subkeys in key listings. Defaults to no.

889

.IP "show-keyring" 10

890

Display the keyring name at the head of key listings to show which

891

keyring a given key resides on. Defaults to no.

892

.IP "show-sig-expire" 10

893

Show signature expiration dates (if any) during \-\-list-sigs or

894

\-\-check-sigs listings. Defaults to no.

895

.IP "show-sig-subpackets" 10

896

Include signature subpackets in the key listing. This option can take

897

an optional argument list of the subpackets to list. If no argument

898

is passed, list all subpackets. Defaults to no. This option is only

899

meaningful when using \-\-with-colons along with \-\-list-sigs or

900

\-\-check-sigs.

901

.RE

902

.IP "\-\-verify-options \fBparameters\fR" 10

903

This is a space or comma delimited string that gives options used when

904

verifying signatures. Options can be prepended with a `no-' to give

905

the opposite meaning. The options are:

906

.RS

907

.IP "show-photos" 10

908

Display any photo IDs present on the key that issued the signature.

909

Defaults to no. See also \-\-photo-viewer.

910

.IP "show-policy-urls" 10

911

Show policy URLs in the signature being verified. Defaults to no.

912

.IP "show-notations" 10

913

.IP "show-std-notations" 10

914

.IP "show-user-notations" 10

915

Show all, IETF standard, or user-defined signature notations in the

916

signature being verified. Defaults to IETF standard.

917

.IP "show-keyserver-urls" 10

918

Show any preferred keyserver URL in the signature being verified.

919

Defaults to no.

920

.IP "show-uid-validity" 10

921

Display the calculated validity of the user IDs on the key that issued

922

the signature. Defaults to no.

923

.IP "show-unusable-uids" 10

924

Show revoked and expired user IDs during signature verification.

925

Defaults to no.

926

.IP "pka-lookups" 10

927

Enable PKA lookups to verify sender addresses. Note that PKA is based

928

on DNS, and so enabling this option may disclose information on when

929

and what signatures are verified or to whom data is encrypted. This

930

is similar to the "web bug" described for the auto-key-retrieve

931

feature.

932

.IP "pka-trust-increase" 10

933

Raise the trust in a signature to full if the signature passes PKA

934

validation. This option is only meaningful if pka-lookups is set.

935

.RE

936

.IP "\-\-enable-dsa2" 10

937

.IP "\-\-disable-dsa2" 10

938

Enables new-style DSA keys which (unlike the old style) may be larger

939

than 1024 bit and use hashes other than SHA-1 and RIPEMD/160. Note

940

that very few programs currently support these keys and signatures

941

from them.

942

.IP "\-\-show-photos" 10

943

.IP "\-\-no-show-photos" 10

944

Causes \-\-list-keys, \-\-list-sigs, \-\-list-public-keys,

945

\-\-list-secret-keys, and verifying a signature to also display the

946

photo ID attached to the key, if any. See also \-\-photo-viewer. These

947

options are deprecated. Use `\-\-list-options [no-]show-photos' and/or

948

`\-\-verify-options [no-]show-photos' instead.

949

.IP "\-\-photo-viewer \fBstring\fR" 10

950

This is the command line that should be run to view a photo ID. "%i"

951

will be expanded to a filename containing the photo. "%I" does the

952

same, except the file will not be deleted once the viewer exits.

953

Other flags are "%k" for the key ID, "%K" for the long key ID, "%f"

954

for the key fingerprint, "%t" for the extension of the image type

955

(e.g. "jpg"), "%T" for the MIME type of the image (e.g. "image/jpeg"),

956

and "%%" for an actual percent sign. If neither %i or %I are present,

957

then the photo will be supplied to the viewer on standard input.

958

.IP "" 10

959

The default viewer is "xloadimage \-fork \-quiet \-title 'KeyID 0x%k'

960

stdin". Note that if your image viewer program is not secure, then

961

executing it from GnuPG does not make it secure.

962

.IP "\-\-exec-path \fBstring\fR" 10

963

Sets a list of directories to search for photo viewers and keyserver

964

helpers. If not provided, keyserver helpers use the compiled-in

965

default directory, and photo viewers use the $PATH environment

966

variable.

967

Note, that on W32 system this value is ignored when searching for

968

keyserver helpers.

969

.IP "\-\-show-keyring" 10

970

Display the keyring name at the head of key listings to show which

971

keyring a given key resides on. This option is deprecated: use

972

`\-\-list-options [no-]show-keyring' instead.

973

.IP "\-\-keyring \fBfile\fR" 10

974

Add \fBfile\fR to the current list of keyrings. If \fBfile\fR begins

975

with a tilde and a slash, these are replaced by the $HOME

976

directory. If the filename does not contain a slash, it is assumed to

977

be in the GnuPG home directory ("~/.gnupg" if \-\-homedir or $GNUPGHOME

978

is not used).

979

.IP "" 10

980

Note that this adds a keyring to the current list. If the intent is

981

to use the specified keyring alone, use \-\-keyring along with

982

\-\-no-default-keyring.

983

.IP "\-\-secret-keyring \fBfile\fR" 10

984

Same as \-\-keyring but for the secret keyrings.

985

.IP "\-\-primary-keyring \fBfile\fR" 10

986

Designate \fBfile\fR as the primary public keyring. This means that

987

newly imported keys (via \-\-import or keyserver \-\-recv-from) will go to

988

this keyring.

989

.IP "\-\-trustdb-name \fBfile\fR" 10

990

Use \fBfile\fR instead of the default trustdb. If \fBfile\fR begins

991

with a tilde and a slash, these are replaced by the $HOME

992

directory. If the filename does not contain a slash, it is assumed to

993

be in the GnuPG home directory ("~/.gnupg" if \-\-homedir or $GNUPGHOME

994

is not used).

995

.IP "\-\-homedir \fBdirectory\fR" 10

996

Set the name of the home directory to \fBdirectory\fR If this option is not

997

used it defaults to "~/.gnupg". It does not make sense to use this in

998

a options file. This also overrides the environment variable

999

$GNUPGHOME.

1000

.IP "\-\-pcsc-driver \fBfile\fR" 10

1001

Use \fBfile\fR to access the smartcard reader. The current default is

1002

`libpcsclite.so.1' for GLIBC based systems,

1003

`/System/Library/Frameworks/PCSC.framework/PCSC' for MAC OS X,

1004

`winscard.dll' for Windows and `libpcsclite.so' for other systems.

1005

.IP "\-\-ctapi-driver \fBfile\fR" 10

1006

Use \fBfile\fR to access the smartcard reader. The current default

1007

is `libtowitoko.so'. Note that the use of this interface is

1008

deprecated; it may be removed in future releases.

1009

.IP "\-\-disable-ccid" 10

1010

Disable the integrated support for CCID compliant readers. This

1011

allows to fall back to one of the other drivers even if the internal

1012

CCID driver can handle the reader. Note, that CCID support is only

1013

available if libusb was available at build time.

1014

.IP "\-\-reader-port \fBnumber_or_string\fR" 10

1015

This option may be used to specify the port of the card terminal. A

1016

value of 0 refers to the first serial device; add 32768 to access USB

1017

devices. The default is 32768 (first USB device). PC/SC or CCID

1018

readers might need a string here; run the program in verbose mode to get

1019

a list of available readers. The default is then the first reader

1020

found.

1021

.IP "\-\-display-charset \fBname\fR" 10

1022

Set the name of the native character set. This is used to convert

1023

some informational strings like user IDs to the proper UTF-8 encoding.

1024

Note that this has nothing to do with the character set of data to be

1025

encrypted or signed; GnuPG does not recode user supplied data. If

1026

this option is not used, the default character set is determined from

1027

the current locale. A verbosity level of 3 shows the chosen set.

1028

Valid values for \fBname\fR are:

1029

.RS

1030

.IP "iso-8859-1" 10

1031

This is the Latin 1 set.

1032

.IP "iso-8859-2" 10

1033

The Latin 2 set.

1034

.IP "iso-8859-15" 10

1035

This is currently an alias for

1036

the Latin 1 set.

1037

.IP "koi8-r" 10

1038

The usual Russian set (rfc1489).

1039

.IP "utf-8" 10

1040

Bypass all translations and assume

1041

that the OS uses native UTF-8 encoding.

1042

.RE

1043

.IP "\-\-utf8-strings" 10

1044

.IP "\-\-no-utf8-strings" 10

1045

Assume that command line arguments are given as UTF8 strings. The

1046

default (\-\-no-utf8-strings) is to assume that arguments are encoded in

1047

the character set as specified by \-\-display-charset. These options

1048

affect all following arguments. Both options may be used multiple

1049

times.

1050

.IP "\-\-options \fBfile\fR" 10

1051

Read options from \fBfile\fR and do not try to read

1052

them from the default options file in the homedir

1053

(see \-\-homedir). This option is ignored if used

1054

in an options file.

1055

.IP "\-\-no-options" 10

1056

Shortcut for "\-\-options /dev/null". This option is

1057

detected before an attempt to open an option file.

1058

Using this option will also prevent the creation of a

1059

"~./gnupg" homedir.

1060

.IP "\-\-load-extension \fBname\fR" 10

1061

Load an extension module. If \fBname\fR does not contain a slash it is

1062

searched for in the directory configured when GnuPG was built

1063

(generally "/usr/local/lib/gnupg"). Extensions are not generally

1064

useful anymore, and the use of this option is deprecated.

1065

.IP "\-\-debug \fBflags\fR" 10

1066

Set debugging flags. All flags are or-ed and \fBflags\fR may

1067

be given in C syntax (e.g. 0x0042).

1068

.IP "\-\-debug-all" 10

1069

Set all useful debugging flags.

1070

.IP "\-\-debug-ccid-driver" 10

1071

Enable debug output from the included CCID driver for smartcards.

1072

Note that this option is only available on some system.

1073

.IP "\-\-enable-progress-filter" 10

1074

Enable certain PROGRESS status outputs. This option allows frontends

1075

to display a progress indicator while gpg is processing larger files.

1076

There is a slight performance overhead using it.

1077

.IP "\-\-status-fd \fBn\fR" 10

1078

Write special status strings to the file descriptor \fBn\fR.

1079

See the file DETAILS in the documentation for a listing of them.

1080

.IP "\-\-status-file \fBfile\fR" 10

1081

Same as \-\-status-fd, except the status data is written to file

1082

\fBfile\fR.

1083

.IP "\-\-logger-fd \fBn\fR" 10

1084

Write log output to file descriptor \fBn\fR and not to stderr.

1085

.IP "\-\-logger-file \fBfile\fR" 10

1086

Same as \-\-logger-fd, except the logger data is written to file

1087

\fBfile\fR.

1088

.IP "\-\-attribute-fd \fBn\fR" 10

1089

Write attribute subpackets to the file descriptor \fBn\fR. This is

1090

most useful for use with \-\-status-fd, since the status messages are

1091

needed to separate out the various subpackets from the stream

1092

delivered to the file descriptor.

1093

.IP "\-\-attribute-file \fBfile\fR" 10

1094

Same as \-\-attribute-fd, except the attribute data is written to file

1095

\fBfile\fR.

1096

.IP "\-\-comment \fBstring\fR" 10

1097

.IP "\-\-no-comments" 10

1098

Use \fBstring\fR as a comment string in clear text signatures and

1099

ASCII armored messages or keys (see \-\-armor). The default behavior is

1100

not to use a comment string. \-\-comment may be repeated multiple times

1101

to get multiple comment strings. \-\-no-comments removes all comments.

1102

It is a good idea to keep the length of a single comment below 60

1103

characters to avoid problems with mail programs wrapping such lines.

1104

Note that comment lines, like all other header lines, are not

1105

protected by the signature.

1106

.IP "\-\-emit-version" 10

1107

.IP "\-\-no-emit-version" 10

1108

Force inclusion of the version string in ASCII armored output.

1109

\-\-no-emit-version disables this option.

1110

.IP "\-\-sig-notation \fBname=value\fR" 10

1111

.IP "\-\-cert-notation \fBname=value\fR" 10

1112

.IP "\-N, \-\-set-notation \fBname=value\fR" 10

1113

Put the name value pair into the signature as notation data.

1114

\fBname\fR must consist only of printable characters or spaces, and

1115

must contain a '@' character in the form keyname@domain.example.com

1116

(substituting the appropriate keyname and domain name, of course).

1117

This is to help prevent pollution of the IETF reserved notation

1118

namespace. The \-\-expert flag overrides the '@' check. \fBvalue\fR may be any printable string; it will be encoded in UTF8, so you should

1119

check that your \-\-display-charset is set correctly. If you prefix

1120

\fBname\fR with an exclamation mark (!), the notation data will be

1121

flagged as critical (rfc2440:5.2.3.15). \-\-sig-notation sets a

1122

notation for data signatures. \-\-cert-notation sets a notation for key

1123

signatures (certifications). \-\-set-notation sets both.

1124

.IP "" 10

1125

There are special codes that may be used in notation names. "%k" will

1126

be expanded into the key ID of the key being signed, "%K" into the

1127

long key ID of the key being signed, "%f" into the fingerprint of the

1128

key being signed, "%s" into the key ID of the key making the

1129

signature, "%S" into the long key ID of the key making the signature,

1130

"%g" into the fingerprint of the key making the signature (which might

1131

be a subkey), "%p" into the fingerprint of the primary key of the key

1132

making the signature, "%c" into the signature count from the OpenPGP

1133

smartcard, and "%%" results in a single "%". %k, %K, and %f are only

1134

meaningful when making a key signature (certification), and %c is only

1135

meaningful when using the OpenPGP smartcard.

1136

.IP "\-\-show-notation" 10

1137

.IP "\-\-no-show-notation" 10

1138

Show signature notations in the \-\-list-sigs or \-\-check-sigs listings

1139

as well as when verifying a signature with a notation in it. These

1140

options are deprecated. Use `\-\-list-options [no-]show-notation'

1141

and/or `\-\-verify-options [no-]show-notation' instead.

1142

.IP "\-\-sig-policy-url \fBstring\fR" 10

1143

.IP "\-\-cert-policy-url \fBstring\fR" 10

1144

.IP "\-\-set-policy-url \fBstring\fR" 10

1145

Use \fBstring\fR as a Policy URL for signatures (rfc2440:5.2.3.19).

1146

If you prefix it with an exclamation mark (!), the policy URL packet

1147

will be flagged as critical. \-\-sig-policy-url sets a policy url for

1148

data signatures. \-\-cert-policy-url sets a policy url for key

1149

signatures (certifications). \-\-set-policy-url sets both.

1150

.IP "" 10

1151

The same %\-expandos used for notation data are available here as well.

1152

.IP "\-\-show-policy-url" 10

1153

.IP "\-\-no-show-policy-url" 10

1154

Show policy URLs in the \-\-list-sigs or \-\-check-sigs listings as well

1155

as when verifying a signature with a policy URL in it. These options

1156

are deprecated. Use `\-\-list-options [no-]show-policy-url' and/or

1157

`\-\-verify-options [no-]show-policy-url' instead.

1158

.IP "\-\-sig-keyserver-url \fBstring\fR" 10

1159

Use \fBstring\fR as a preferred keyserver URL for data signatures. If

1160

you prefix it with an exclamation mark, the keyserver URL packet will

1161

be flagged as critical.

1162

.IP "" 10

1163

The same %\-expandos used for notation data are available here as well.

1164

.IP "\-\-set-filename \fBstring\fR" 10

1165

Use \fBstring\fR as the filename which is stored inside messages.

1166

This overrides the default, which is to use the actual filename of the

1167

file being encrypted.

1168

.IP "\-\-for-your-eyes-only" 10

1169

.IP "\-\-no-for-your-eyes-only" 10

1170

Set the `for your eyes only' flag in the message. This causes GnuPG

1171

to refuse to save the file unless the \-\-output option is given, and

1172

PGP to use the "secure viewer" with a Tempest-resistant font to

1173

display the message. This option overrides \-\-set-filename.

1174

\-\-no-for-your-eyes-only disables this option.

1175

.IP "\-\-use-embedded-filename" 10

1176

.IP "\-\-no-use-embedded-filename" 10

1177

Try to create a file with a name as embedded in the data. This can be

1178

a dangerous option as it allows to overwrite files. Defaults to no.

1179

.IP "\-\-completes-needed \fBn\fR" 10

1180

Number of completely trusted users to introduce a new

1181

key signer (defaults to 1).

1182

.IP "\-\-marginals-needed \fBn\fR" 10

1183

Number of marginally trusted users to introduce a new

1184

key signer (defaults to 3)

1185

.IP "\-\-max-cert-depth \fBn\fR" 10

1186

Maximum depth of a certification chain (default is 5).

1187

.IP "\-\-cipher-algo \fBname\fR" 10

1188

Use \fBname\fR as cipher algorithm. Running the program with the

1189

command \-\-version yields a list of supported algorithms. If this is

1190

not used the cipher algorithm is selected from the preferences stored

1191

with the key. In general, you do not want to use this option as it

1192

allows you to violate the OpenPGP standard.

1193

\-\-personal-cipher-preferences is the safe way to accomplish the same

1194

thing.

1195

.IP "\-\-digest-algo \fBname\fR" 10

1196

Use \fBname\fR as the message digest algorithm. Running the program

1197

with the command \-\-version yields a list of supported algorithms. In

1198

general, you do not want to use this option as it allows you to

1199

violate the OpenPGP standard. \-\-personal-digest-preferences is the

1200

safe way to accomplish the same thing.

1201

.IP "\-\-compress-algo \fBname\fR" 10

1202

Use compression algorithm \fBname\fR. "zlib" is RFC-1950 ZLIB

1203

compression. "zip" is RFC-1951 ZIP compression which is used by PGP.

1204

"bzip2" is a more modern compression scheme that can compress some

1205

things better than zip or zlib, but at the cost of more memory used

1206

during compression and decompression. "uncompressed" or "none"

1207

disables compression. If this option is not used, the default

1208

behavior is to examine the recipient key preferences to see which

1209

algorithms the recipient supports. If all else fails, ZIP is used for

1210

maximum compatibility.

1211

.IP "" 10

1212

ZLIB may give better compression results than ZIP, as the compression

1213

window size is not limited to 8k. BZIP2 may give even better

1214

compression results than that, but will use a significantly larger

1215

amount of memory while compressing and decompressing. This may be

1216

significant in low memory situations. Note, however, that PGP (all

1217

versions) only supports ZIP compression. Using any algorithm other

1218

than ZIP or "none" will make the message unreadable with PGP. In

1219

general, you do not want to use this option as it allows you to

1220

violate the OpenPGP standard. \-\-personal-compress-preferences is the

1221

safe way to accomplish the same thing.

1222

.IP "\-\-cert-digest-algo \fBname\fR" 10

1223

Use \fBname\fR as the message digest algorithm used when signing a

1224

key. Running the program with the command \-\-version yields a list of

1225

supported algorithms. Be aware that if you choose an algorithm that

1226

GnuPG supports but other OpenPGP implementations do not, then some

1227

users will not be able to use the key signatures you make, or quite

1228

possibly your entire key.

1229

.IP "\-\-s2k-cipher-algo \fBname\fR" 10

1230

Use \fBname\fR as the cipher algorithm used to protect secret keys.

1231

The default cipher is CAST5. This cipher is also used for

1232

conventional encryption if \-\-personal-cipher-preferences and

1233

\-\-cipher-algo is not given.

1234

.IP "\-\-s2k-digest-algo \fBname\fR" 10

1235

Use \fBname\fR as the digest algorithm used to mangle the passphrases.

1236

The default algorithm is SHA-1.

1237

.IP "\-\-s2k-mode \fBn\fR" 10

1238

Selects how passphrases are mangled. If \fBn\fR is 0 a plain

1239

passphrase (which is not recommended) will be used, a 1 adds a salt to

1240

the passphrase and a 3 (the default) iterates the whole process a

1241

couple of times. Unless \-\-rfc1991 is used, this mode is also used for

1242

conventional encryption.

1243

.IP "\-\-simple-sk-checksum" 10

1244

Secret keys are integrity protected by using a SHA-1 checksum. This

1245

method is part of the upcoming enhanced OpenPGP specification but

1246

GnuPG already uses it as a countermeasure against certain attacks.

1247

Old applications don't understand this new format, so this option may

1248

be used to switch back to the old behaviour. Using this option bears

1249

a security risk. Note that using this option only takes effect when

1250

the secret key is encrypted \- the simplest way to make this happen is

1251

to change the passphrase on the key (even changing it to the same

1252

value is acceptable).

1253

.IP "\-\-disable-cipher-algo \fBname\fR" 10

1254

Never allow the use of \fBname\fR as cipher algorithm.

1255

The given name will not be checked so that a later loaded algorithm

1256

will still get disabled.

1257

.IP "\-\-disable-pubkey-algo \fBname\fR" 10

1258

Never allow the use of \fBname\fR as public key algorithm.

1259

The given name will not be checked so that a later loaded algorithm

1260

will still get disabled.

1261

.IP "\-\-no-sig-cache" 10

1262

Do not cache the verification status of key signatures.

1263

Caching gives a much better performance in key listings. However, if

1264

you suspect that your public keyring is not save against write

1265

modifications, you can use this option to disable the caching. It

1266

probably does not make sense to disable it because all kind of damage

1267

can be done if someone else has write access to your public keyring.

1268

.IP "\-\-no-sig-create-check" 10

1269

GnuPG normally verifies each signature right after creation to protect

1270

against bugs and hardware malfunctions which could leak out bits from

1271

the secret key. This extra verification needs some time (about 115%

1272

for DSA keys), and so this option can be used to disable it.

1273

However, due to the fact that the signature creation needs manual

1274

interaction, this performance penalty does not matter in most settings.

1275

.IP "\-\-auto-check-trustdb" 10

1276

.IP "\-\-no-auto-check-trustdb" 10

1277

If GnuPG feels that its information about the Web of Trust has to be

1278

updated, it automatically runs the \-\-check-trustdb command internally.

1279

This may be a time consuming process. \-\-no-auto-check-trustdb

1280

disables this option.

1281

.IP "\-\-throw-keyids" 10

1282

.IP "\-\-no-throw-keyids" 10

1283

Do not put the recipient key IDs into encrypted messages. This helps

1284

to hide the receivers of the message and is a limited countermeasure

1285

against traffic analysis. On the receiving side, it may slow down the

1286

decryption process because all available secret keys must be tried.

1287

\-\-no-throw-keyids disables this option. This option is essentially

1288

the same as using \-\-hidden-recipient for all recipients.

1289

.IP "\-\-not-dash-escaped" 10

1290

This option changes the behavior of cleartext signatures

1291

so that they can be used for patch files. You should not

1292

send such an armored file via email because all spaces

1293

and line endings are hashed too. You can not use this

1294

option for data which has 5 dashes at the beginning of a

1295

line, patch files don't have this. A special armor header

1296

line tells GnuPG about this cleartext signature option.

1297

.IP "\-\-escape-from-lines" 10

1298

.IP "\-\-no-escape-from-lines" 10

1299

Because some mailers change lines starting with "From " to ">From

1300

" it is good to handle such lines in a special way when creating

1301

cleartext signatures to prevent the mail system from breaking the

1302

signature. Note that all other PGP versions do it this way too.

1303

Enabled by default. \-\-no-escape-from-lines disables this option.

1304

.IP "\-\-passphrase-fd \fBn\fR" 10

1305

Read the passphrase from file descriptor \fBn\fR. Only the first line

1306

will be read from file descriptor \fBn\fR. If you use 0 for \fBn\fR,

1307

the passphrase will be read from stdin. This can only be used if only

1308

one passphrase is supplied.

1309

.IP "\-\-passphrase-file \fBfile\fR" 10

1310

Read the passphrase from file \fBfile\fR. Only the first line will

1311

be read from file \fBfile\fR. This can only be used if only one

1312

passphrase is supplied. Obviously, a passphrase stored in a file is

1313

of questionable security if other users can read this file. Don't use

1314

this option if you can avoid it.

1315

.IP "\-\-passphrase \fBstring\fR" 10

1316

Use \fBstring\fR as the passphrase. This can only be used if only one

1317

passphrase is supplied. Obviously, this is of very questionable

1318

security on a multi-user system. Don't use this option if you can

1319

avoid it.

1320

.IP "\-\-command-fd \fBn\fR" 10

1321

This is a replacement for the deprecated shared-memory IPC mode.

1322

If this option is enabled, user input on questions is not expected

1323

from the TTY but from the given file descriptor. It should be used

1324

together with \-\-status-fd. See the file doc/DETAILS in the source

1325

distribution for details on how to use it.

1326

.IP "\-\-command-file \fBfile\fR" 10

1327

Same as \-\-command-fd, except the commands are read out of file

1328

\fBfile\fR

1329

.IP "\-\-use-agent" 10

1330

.IP "\-\-no-use-agent" 10

1331

Try to use the GnuPG-Agent. Please note that this agent is still under

1332

development. With this option, GnuPG first tries to connect to the

1333

agent before it asks for a passphrase. \-\-no-use-agent disables this

1334

option.

1335

.IP "\-\-gpg-agent-info" 10

1336

Override the value of the environment variable

1337

\fBGPG_AGENT_INFO\fP. This is only used when \-\-use-agent has been given

1338

.IP "Compliance options" 10

1339

These options control what GnuPG is compliant to. Only one of these

1340

options may be active at a time. Note that the default setting of

1341

this is nearly always the correct one. See the INTEROPERABILITY WITH

1342

OTHER OPENPGP PROGRAMS section below before using one of these

1343

options.

1344

.RS

1345

.IP "\-\-gnupg" 10

1346

Use standard GnuPG behavior. This is essentially OpenPGP behavior

1347

(see \-\-openpgp), but with some additional workarounds for common

1348

compatibility problems in different versions of PGP. This is the

1349

default option, so it is not generally needed, but it may be useful to

1350

override a different compliance option in the gpg.conf file.

1351

.IP "\-\-openpgp" 10

1352

Reset all packet, cipher and digest options to strict OpenPGP

1353

behavior. Use this option to reset all previous options like

1354

\-\-rfc1991, \-\-force-v3-sigs, \-\-s2k-*, \-\-cipher-algo, \-\-digest-algo and

1355

\-\-compress-algo to OpenPGP compliant values. All PGP workarounds are

1356

disabled.

1357

.IP "\-\-rfc2440" 10

1358

Reset all packet, cipher and digest options to strict RFC-2440

1359

behavior. Note that this is currently the same thing as \-\-openpgp.

1360

.IP "\-\-rfc1991" 10

1361

Try to be more RFC-1991 (PGP 2.x) compliant.

1362

.IP "\-\-pgp2" 10

1363

Set up all options to be as PGP 2.x compliant as possible, and warn if

1364

an action is taken (e.g. encrypting to a non-RSA key) that will create

1365

a message that PGP 2.x will not be able to handle. Note that `PGP

1366

2.x' here means `MIT PGP 2.6.2'. There are other versions of PGP 2.x

1367

available, but the MIT release is a good common baseline.

1368

.IP "" 10

1369

This option implies `\-\-rfc1991 \-\-disable-mdc \-\-no-force-v4-certs

1370

\-\-no-sk-comment \-\-escape-from-lines \-\-force-v3-sigs

1371

\-\-no-ask-sig-expire \-\-no-ask-cert-expire \-\-cipher-algo IDEA

1372

\-\-digest-algo MD5 \-\-compress-algo 1'. It also disables \-\-textmode

1373

when encrypting.

1374

.IP "\-\-pgp6" 10

1375

Set up all options to be as PGP 6 compliant as possible. This

1376

restricts you to the ciphers IDEA (if the IDEA plugin is installed),

1377

3DES, and CAST5, the hashes MD5, SHA1 and RIPEMD160, and the

1378

compression algorithms none and ZIP. This also disables

1379

\-\-throw-keyids, and making signatures with signing subkeys as PGP 6

1380

does not understand signatures made by signing subkeys.

1381

.IP "" 10

1382

This option implies `\-\-disable-mdc \-\-no-sk-comment \-\-escape-from-lines

1383

\-\-force-v3-sigs \-\-no-ask-sig-expire'

1384

.IP "\-\-pgp7" 10

1385

Set up all options to be as PGP 7 compliant as possible. This is

1386

identical to \-\-pgp6 except that MDCs are not disabled, and the list of

1387

allowable ciphers is expanded to add AES128, AES192, AES256, and

1388

TWOFISH.

1389

.IP "\-\-pgp8" 10

1390

Set up all options to be as PGP 8 compliant as possible. PGP 8 is a

1391

lot closer to the OpenPGP standard than previous versions of PGP, so

1392

all this does is disable \-\-throw-keyids and set \-\-escape-from-lines.

1393

All algorithms are allowed except for the SHA224, SHA384, and SHA512

1394

digests.

1395

.RE

1396

.IP "\-\-force-v3-sigs" 10

1397

.IP "\-\-no-force-v3-sigs" 10

1398

OpenPGP states that an implementation should generate v4 signatures

1399

but PGP versions 5 through 7 only recognize v4 signatures on key

1400

material. This option forces v3 signatures for signatures on data.

1401

Note that this option overrides \-\-ask-sig-expire, as v3 signatures

1402

cannot have expiration dates. \-\-no-force-v3-sigs disables this

1403

option.

1404

.IP "\-\-force-v4-certs" 10

1405

.IP "\-\-no-force-v4-certs" 10

1406

Always use v4 key signatures even on v3 keys. This option also

1407

changes the default hash algorithm for v3 RSA keys from MD5 to SHA-1.

1408

\-\-no-force-v4-certs disables this option.

1409

.IP "\-\-force-mdc" 10

1410

Force the use of encryption with a modification detection code. This

1411

is always used with the newer ciphers (those with a blocksize greater

1412

than 64 bits), or if all of the recipient keys indicate MDC support in

1413

their feature flags.

1414

.IP "\-\-disable-mdc" 10

1415

Disable the use of the modification detection code. Note that by

1416

using this option, the encrypted message becomes vulnerable to a

1417

message modification attack.

1418

.IP "\-\-allow-non-selfsigned-uid" 10

1419

.IP "\-\-no-allow-non-selfsigned-uid" 10

1420

Allow the import and use of keys with user IDs which are not

1421

self-signed. This is not recommended, as a non self-signed user ID is

1422

trivial to forge. \-\-no-allow-non-selfsigned-uid disables.

1423

.IP "\-\-allow-freeform-uid" 10

1424

Disable all checks on the form of the user ID while generating a new

1425

one. This option should only be used in very special environments as

1426

it does not ensure the de-facto standard format of user IDs.

1427

.IP "\-\-ignore-time-conflict" 10

1428

GnuPG normally checks that the timestamps associated with keys and

1429

signatures have plausible values. However, sometimes a signature

1430

seems to be older than the key due to clock problems. This option

1431

makes these checks just a warning. See also \-\-ignore-valid-from for

1432

timestamp issues on subkeys.

1433

.IP "\-\-ignore-valid-from" 10

1434

GnuPG normally does not select and use subkeys created in the future.

1435

This option allows the use of such keys and thus exhibits the

1436

pre-1.0.7 behaviour. You should not use this option unless you there

1437

is some clock problem. See also \-\-ignore-time-conflict for timestamp

1438

issues with signatures.

1439

.IP "\-\-ignore-crc-error" 10

1440

The ASCII armor used by OpenPGP is protected by a CRC checksum against

1441

transmission errors. Occasionally the CRC gets mangled somewhere on

1442

the transmission channel but the actual content (which is protected by

1443

the OpenPGP protocol anyway) is still okay. This option allows GnuPG

1444

to ignore CRC errors.

1445

.IP "\-\-ignore-mdc-error" 10

1446

This option changes a MDC integrity protection failure into a warning.

1447

This can be useful if a message is partially corrupt, but it is

1448

necessary to get as much data as possible out of the corrupt message.

1449

However, be aware that a MDC protection failure may also mean that the

1450

message was tampered with intentionally by an attacker.

1451

.IP "\-\-lock-once" 10

1452

Lock the databases the first time a lock is requested

1453

and do not release the lock until the process

1454

terminates.

1455

.IP "\-\-lock-multiple" 10

1456

Release the locks every time a lock is no longer

1457

needed. Use this to override a previous \-\-lock-once

1458

from a config file.

1459

.IP "\-\-lock-never" 10

1460

Disable locking entirely. This option should be used only in very

1461

special environments, where it can be assured that only one process

1462

is accessing those files. A bootable floppy with a stand-alone

1463

encryption system will probably use this. Improper usage of this

1464

option may lead to data and key corruption.

1465

.IP "\-\-exit-on-status-write-error" 10

1466

This option will cause write errors on the status FD to immediately

1467

terminate the process. That should in fact be the default but it

1468

never worked this way and thus we need an option to enable this, so

1469

that the change won't break applications which close their end of a

1470

status fd connected pipe too early. Using this option along with

1471

\-\-enable-progress-filter may be used to cleanly cancel long running

1472

gpg operations.

1473

.IP "\-\-limit-card-insert-tries \fBn\fR" 10

1474

With \fBn\fR greater than 0 the number of prompts asking to insert a

1475

smartcard gets limited to N-1. Thus with a value of 1 gpg won't at

1476

all ask to insert a card if none has been inserted at startup. This

1477

option is useful in the configuration file in case an application does

1478

not know about the smartcard support and waits ad infinitum for an

1479

inserted card.

1480

.IP "\-\-no-random-seed-file" 10

1481

GnuPG uses a file to store its internal random pool over invocations.

1482

This makes random generation faster; however sometimes write operations

1483

are not desired. This option can be used to achieve that with the cost of

1484

slower random generation.

1485

.IP "\-\-no-verbose" 10

1486

Reset verbose level to 0.

1487

.IP "\-\-no-greeting" 10

1488

Suppress the initial copyright message.

1489

.IP "\-\-no-secmem-warning" 10

1490

Suppress the warning about "using insecure memory".

1491

.IP "\-\-no-permission-warning" 10

1492

Suppress the warning about unsafe file and home directory (\-\-homedir)

1493

permissions. Note that the permission checks that GnuPG performs are

1494

not intended to be authoritative, but rather they simply warn about

1495

certain common permission problems. Do not assume that the lack of a

1496

warning means that your system is secure.

1497

.IP "" 10

1498

Note that the warning for unsafe \-\-homedir permissions cannot be

1499

suppressed in the gpg.conf file, as this would allow an attacker to

1500

place an unsafe gpg.conf file in place, and use this file to suppress

1501

warnings about itself. The \-\-homedir permissions warning may only be

1502

suppressed on the command line.

1503

.IP "\-\-no-mdc-warning" 10

1504

Suppress the warning about missing MDC integrity protection.

1505

.IP "\-\-require-secmem" 10

1506

.IP "\-\-no-require-secmem" 10

1507

Refuse to run if GnuPG cannot get secure memory. Defaults to no

1508

(i.e. run, but give a warning).

1509

.IP "\-\-no-armor" 10

1510

Assume the input data is not in ASCII armored format.

1511

.IP "\-\-no-default-keyring" 10

1512

Do not add the default keyrings to the list of keyrings. Note that

1513

GnuPG will not operate without any keyrings, so if you use this option

1514

and do not provide alternate keyrings via \-\-keyring or

1515

\-\-secret-keyring, then GnuPG will still use the default public or

1516

secret keyrings.

1517

.IP "\-\-skip-verify" 10

1518

Skip the signature verification step. This may be

1519

used to make the decryption faster if the signature

1520

verification is not needed.

1521

.IP "\-\-with-colons" 10

1522

Print key listings delimited by colons. Note that the output will be

1523

encoded in UTF-8 regardless of any \-\-display-charset setting. This

1524

format is useful when GnuPG is called from scripts and other programs

1525

as it is easily machine parsed. The details of this format are

1526

documented in the file doc/DETAILS, which is included in the GnuPG

1527

source distribution.

1528

.IP "\-\-with-key-data" 10

1529

Print key listings delimited by colons (like \-\-with-colons) and print the public key data.

1530

.IP "\-\-with-fingerprint" 10

1531

Same as the command \-\-fingerprint but changes only the format of the output

1532

and may be used together with another command.

1533

.IP "\-\-fast-list-mode" 10

1534

Changes the output of the list commands to work faster; this is achieved

1535

by leaving some parts empty. Some applications don't need the user ID and

1536

the trust information given in the listings. By using this options they

1537

can get a faster listing. The exact behaviour of this option may change

1538

in future versions.

1539

.IP "\-\-fixed-list-mode" 10

1540

Do not merge primary user ID and primary key in \-\-with-colon listing

1541

mode and print all timestamps as seconds since 1970-01-01.

1542

.IP "\-\-list-only" 10

1543

Changes the behaviour of some commands. This is like \-\-dry-run but

1544

different in some cases. The semantic of this command may be extended in

1545

the future. Currently it only skips the actual decryption pass and

1546

therefore enables a fast listing of the encryption keys.

1547

.IP "\-\-no-literal" 10

1548

This is not for normal use. Use the source to see for what it might be useful.

1549

.IP "\-\-set-filesize" 10

1550

This is not for normal use. Use the source to see for what it might be useful.

1551

.IP "\-\-show-session-key" 10

1552

Display the session key used for one message. See \-\-override-session-key

1553

for the counterpart of this option.

1554

.IP "" 10

1555

We think that Key Escrow is a Bad Thing; however the user should have

1556

the freedom to decide whether to go to prison or to reveal the content

1557

of one specific message without compromising all messages ever

1558

encrypted for one secret key. DON'T USE IT UNLESS YOU ARE REALLY

1559

FORCED TO DO SO.

1560

.IP "\-\-override-session-key \fBstring\fR" 10

1561

Don't use the public key but the session key \fBstring\fR. The format of this

1562

string is the same as the one printed by \-\-show-session-key. This option

1563

is normally not used but comes handy in case someone forces you to reveal the

1564

content of an encrypted message; using this option you can do this without

1565

handing out the secret key.

1566

.IP "\-\-require-cross-certification" 10

1567

.IP "\-\-no-require-certification" 10

1568

When verifying a signature made from a subkey, ensure that the cross

1569

certification "back signature" on the subkey is present and valid.

1570

This protects against a subtle attack against subkeys that can sign.

1571

Currently defaults to \-\-no-require-cross-certification, but will be

1572

changed to \-\-require-cross-certification in the future.

1573

.IP "\-\-ask-sig-expire" 10

1574

.IP "\-\-no-ask-sig-expire" 10

1575

When making a data signature, prompt for an expiration time. If this

1576

option is not specified, the expiration time set via

1577

\-\-default-sig-expire is used. \-\-no-ask-sig-expire disables this

1578

option. Note that by default, \-\-force-v3-sigs is set which also

1579

disables this option. If you want signature expiration, you must set

1580

\-\-no-force-v3-sigs as well as turning \-\-ask-sig-expire on.

1581

.IP "\-\-default-sig-expire" 10

1582

The default expiration time to use for signature expiration. Valid

1583

values are "0" for no expiration, a number followed by the letter d

1584

(for days), w (for weeks), m (for months), or y (for years) (for

1585

example "2m" for two months, or "5y" for five years), or an absolute

1586

date in the form YYYY-MM-DD. Defaults to "0".

1587

.IP "\-\-ask-cert-expire" 10

1588

.IP "\-\-no-ask-cert-expire" 10

1589

When making a key signature, prompt for an expiration time. If this

1590

option is not specified, the expiration time set via

1591

\-\-default-cert-expire is used. \-\-no-ask-cert-expire disables this

1592

option.

1593

.IP "\-\-default-cert-expire" 10

1594

The default expiration time to use for key signature expiration.

1595

Valid values are "0" for no expiration, a number followed by the

1596

letter d (for days), w (for weeks), m (for months), or y (for years)

1597

(for example "2m" for two months, or "5y" for five years), or an

1598

absolute date in the form YYYY-MM-DD. Defaults to "0".

1599

.IP "\-\-expert" 10

1600

.IP "\-\-no-expert" 10

1601

Allow the user to do certain nonsensical or "silly" things like

1602

signing an expired or revoked key, or certain potentially incompatible

1603

things like generating unusual key types. This also disables certain

1604

warning messages about potentially incompatible actions. As the name

1605

implies, this option is for experts only. If you don't fully

1606

understand the implications of what it allows you to do, leave this

1607

off. \-\-no-expert disables this option.

1608

.IP "\-\-allow-secret-key-import" 10

1609

This is an obsolete option and is not used anywhere.

1610

.IP "\-\-try-all-secrets" 10

1611

Don't look at the key ID as stored in the message but try all secret

1612

keys in turn to find the right decryption key. This option forces the

1613

behaviour as used by anonymous recipients (created by using

1614

\-\-throw-keyids) and might come handy in case where an encrypted

1615

message contains a bogus key ID.

1616

.IP "\-\-allow-multisig-verification" 10

1617

Allow verification of concatenated signed messages. This will run a

1618

signature verification for each data+signature block. There are some

1619

security issues with this option and thus it is off by default. Note

1620

that versions of GPG prior to version 1.4.3 implicitly allowed this.

1621

.IP "\-\-enable-special-filenames" 10

1622

This options enables a mode in which filenames of the form

1623

\fB-&n\fP, where n is a non-negative decimal number,

1624

refer to the file descriptor n and not to a file with that name.

1625

.IP "\-\-no-expensive-trust-checks" 10

1626

Experimental use only.

1627

.IP "\-\-group \fBname=value1 [value2 value3 ...]\fR" 10

1628

Sets up a named group, which is similar to aliases in email programs.

1629

Any time the group name is a recipient (\-r or \-\-recipient), it will be

1630

expanded to the values specified. Multiple groups with the same name

1631

are automatically merged into a single group.

1632

.IP "" 10

1633

The values are \fBkey IDs\fR or fingerprints, but any key description

1634

is accepted. Note that a value with spaces in it will be treated as

1635

two different values. Note also there is only one level of expansion

1636

\- you cannot make an group that points to another group. When used

1637

from the command line, it may be necessary to quote the argument to

1638

this option to prevent the shell from treating it as multiple

1639

arguments.

1640

.IP "\-\-ungroup \fBname\fR" 10

1641

Remove a given entry from the \-\-group list.

1642

.IP "\-\-no-groups" 10

1643

Remove all entries from the \-\-group list.

1644

.IP "\-\-preserve-permissions" 10

1645

Don't change the permissions of a secret keyring back to user

1646

read/write only. Use this option only if you really know what you are doing.

1647

.IP "\-\-personal-cipher-preferences \fBstring\fR" 10

1648

Set the list of personal cipher preferences to \fBstring\fR, this list

1649

should be a string similar to the one printed by the command "pref" in

1650

the edit menu. This allows the user to factor in their own preferred

1651

algorithms when algorithms are chosen via recipient key preferences.

1652

The most highly ranked cipher in this list is also used for the

1653

\-\-symmetric encryption command.

1654

.IP "\-\-personal-digest-preferences \fBstring\fR" 10

1655

Set the list of personal digest preferences to \fBstring\fR, this list

1656

should be a string similar to the one printed by the command "pref" in

1657

the edit menu. This allows the user to factor in their own preferred

1658

algorithms when algorithms are chosen via recipient key preferences.

1659

The most highly ranked digest algorithm in this list is algo used when

1660

signing without encryption (e.g. \-\-clearsign or \-\-sign). The default

1661

value is SHA-1.

1662

.IP "\-\-personal-compress-preferences \fBstring\fR" 10

1663

Set the list of personal compression preferences to \fBstring\fR, this

1664

list should be a string similar to the one printed by the command

1665

"pref" in the edit menu. This allows the user to factor in their own

1666

preferred algorithms when algorithms are chosen via recipient key

1667

preferences. The most highly ranked algorithm in this list is also

1668

used when there are no recipient keys to consider (e.g. \-\-symmetric).

1669

.IP "\-\-default-preference-list \fBstring\fR" 10

1670

Set the list of default preferences to \fBstring\fR. This preference

1671

list is used for new keys and becomes the default for "setpref" in the

1672

edit menu.

1673

.IP "\-\-default-keyserver-url \fBname\fR" 10

1674

Set the default keyserver URL to \fBname\fR. This keyserver will be

1675

used as the keyserver URL when writing a new self-signature on a key,

1676

which includes key generation and changing preferences.

1677

.IP "\-\-list-config [\fBnames\fR]" 10

1678

Display various internal configuration parameters of GnuPG. This

1679

option is intended for external programs that call GnuPG to perform

1680

tasks, and is thus not generally useful. See the file

1681

\fBdoc/DETAILS\fP in the source distribution for the

1682

details of which configuration items may be listed. \-\-list-config is

1683

only usable with \-\-with-colons set.

1684

.SH "How to specify a user ID"

1685

.PP

1686

There are different ways to specify a user ID to GnuPG; here are some

1687

examples:

1688

1689

.IP "" 10

1690

.IP "234567C4" 10

1691

.IP "0F34E556E" 10

1692

.IP "01347A56A" 10

1693

.IP "0xAB123456" 10

1694

Here the key ID is given in the usual short form.

1695

.IP "234AABBCC34567C4" 10

1696

.IP "0F323456784E56EAB" 10

1697

.IP "01AB3FED1347A5612" 10

1698

.IP "0x234AABBCC34567C4" 10

1699

Here the key ID is given in the long form as used by OpenPGP

1700

(you can get the long key ID using the option \-\-with-colons).

1701

.IP "1234343434343434C434343434343434" 10

1702

.IP "123434343434343C3434343434343734349A3434" 10

1703

.IP "0E12343434343434343434EAB3484343434343434" 10

1704

.IP "0xE12343434343434343434EAB3484343434343434" 10

1705

The best way to specify a key ID is by using the fingerprint of

1706

the key. This avoids any ambiguities in case that there are duplicated

1707

key IDs (which are really rare for the long key IDs).

1708

.IP "=Heinrich Heine <heinrichh@uni-duesseldorf.de>" 10

1709

Using an exact to match string. The equal sign indicates this.

1710

.IP "<heinrichh@uni-duesseldorf.de>" 10

1711

Using the email address part which must match exactly. The left angle bracket

1712

indicates this email address mode.

1713

.IP "@heinrichh" 10

1714

Match within the <email.address> part of a user ID. The at sign

1715

indicates this email address mode.

1716

.IP "Heine" 10

1717

.IP "*Heine" 10

1718

By case insensitive substring matching. This is the default mode but

1719

applications may want to explicitly indicate this by putting the asterisk

1720

in front.

1721

.PP

1722

Note that you can append an exclamation mark (!) to key IDs or

1723

fingerprints. This flag tells GnuPG to use the specified primary or

1724

secondary key and not to try and calculate which primary or secondary

1725

key to use.

1726

1727

.SH "RETURN VALUE"

1728

.PP

1729

The program returns 0 if everything was fine, 1 if at least

1730

a signature was bad, and other error codes for fatal errors.

1731

1732

.SH "EXAMPLES"

1733

.IP "gpg \-se \-r \fBBob\fR \fBfile\fR" 10

1734

sign and encrypt for user Bob

1735

.IP "gpg \-\-clearsign \fBfile\fR" 10

1736

make a clear text signature

1737

.IP "gpg \-sb \fBfile\fR" 10

1738

make a detached signature

1739

.IP "gpg \-\-list-keys \fBuser_ID\fR" 10

1740

show keys

1741

.IP "gpg \-\-fingerprint \fBuser_ID\fR" 10

1742

show fingerprint

1743

.IP "gpg \-\-verify \fBpgpfile\fR" 10

1744

.IP "gpg \-\-verify \fBsigfile\fR [\fBfiles\fR]" 10

1745

Verify the signature of the file but do not output the data. The

1746

second form is used for detached signatures, where \fBsigfile\fR is the detached signature (either ASCII armored or binary) and

1747

[\fBfiles\fR] are the signed data; if this is not given, the name of

1748

the file holding the signed data is constructed by cutting off the

1749

extension (".asc" or ".sig") of \fBsigfile\fR or by asking the

1750

user for the filename.

1751

.SH "ENVIRONMENT"

1752

.IP "HOME" 10

1753

Used to locate the default home directory.

1754

.IP "GNUPGHOME" 10

1755

If set directory used instead of "~/.gnupg".

1756

.IP "GPG_AGENT_INFO" 10

1757

Used to locate the gpg-agent; only honored when

1758

\-\-use-agent is set. The value consists of 3 colon delimited fields:

1759

The first is the path to the Unix Domain Socket, the second the PID of

1760

the gpg-agent and the protocol version which should be set to 1. When

1761

starting the gpg-agent as described in its documentation, this

1762

variable is set to the correct value. The option \-\-gpg-agent-info can

1763

be used to override it.

1764

.IP "COLUMNS" 10

1765

.IP "LINES" 10

1766

Used to size some displays to the full size of the screen.

1767

.SH "FILES"

1768

.IP "~/.gnupg/secring.gpg" 10

1769

The secret keyring

1770

.IP "~/.gnupg/secring.gpg.lock" 10

1771

and the lock file

1772

.IP "~/.gnupg/pubring.gpg" 10

1773

The public keyring

1774

.IP "~/.gnupg/pubring.gpg.lock" 10

1775

and the lock file

1776

.IP "~/.gnupg/trustdb.gpg" 10

1777

The trust database

1778

.IP "~/.gnupg/trustdb.gpg.lock" 10

1779

and the lock file

1780

.IP "~/.gnupg/random_seed" 10

1781

used to preserve the internal random pool

1782

.IP "~/.gnupg/gpg.conf" 10

1783

Default configuration file

1784

.IP "~/.gnupg/options" 10

1785

Old style configuration file; only used when gpg.conf

1786

is not found

1787

.IP "/usr[/local]/share/gnupg/options.skel" 10

1788

Skeleton options file

1789

.IP "/usr[/local]/lib/gnupg/" 10

1790

Default location for extensions

1791

.SH "WARNINGS"

1792

.PP

1793

Use a *good* password for your user account and a *good* passphrase

1794

to protect your secret key. This passphrase is the weakest part of the

1795

whole system. Programs to do dictionary attacks on your secret keyring

1796

are very easy to write and so you should protect your "~/.gnupg/"

1797

directory very well.

1798

.PP

1799

Keep in mind that, if this program is used over a network (telnet), it

1800

is *very* easy to spy out your passphrase!

1801

.PP

1802

If you are going to verify detached signatures, make sure that the

1803

program knows about it; either give both filenames on the command line

1804

or use \fB-\fP to specify stdin.

1805

.SH "INTEROPERABILITY WITH OTHER OPENPGP PROGRAMS"

1806

.PP

1807

GnuPG tries to be a very flexible implementation of the OpenPGP

1808

standard. In particular, GnuPG implements many of the optional parts

1809

of the standard, such as the SHA-512 hash, and the ZLIB and BZIP2

1810

compression algorithms. It is important to be aware that not all

1811

OpenPGP programs implement these optional algorithms and that by

1812

forcing their use via the \-\-cipher-algo, \-\-digest-algo,

1813

\-\-cert-digest-algo, or \-\-compress-algo options in GnuPG, it is

1814

possible to create a perfectly valid OpenPGP message, but one that

1815

cannot be read by the intended recipient.

1816

.PP

1817

There are dozens of variations of OpenPGP programs available, and each

1818

supports a slightly different subset of these optional algorithms.

1819

For example, until recently, no (unhacked) version of PGP supported

1820

the BLOWFISH cipher algorithm. A message using BLOWFISH simply could

1821

not be read by a PGP user. By default, GnuPG uses the standard

1822

OpenPGP preferences system that will always do the right thing and

1823

create messages that are usable by all recipients, regardless of which

1824

OpenPGP program they use. Only override this safe default if you

1825

really know what you are doing.

1826

.PP

1827

If you absolutely must override the safe default, or if the

1828

preferences on a given key are invalid for some reason, you are far

1829

better off using the \-\-pgp6, \-\-pgp7, or \-\-pgp8 options. These options

1830

are safe as they do not force any particular algorithms in violation

1831

of OpenPGP, but rather reduce the available algorithms to a "PGP-safe"

1832

list.

1833

.SH "BUGS"

1834

.PP

1835

On many systems this program should be installed as setuid(root). This

1836

is necessary to lock memory pages. Locking memory pages prevents the

1837

operating system from writing memory pages (which may contain

1838

passphrases or other sensitive material) to disk. If you get no

1839

warning message about insecure memory your operating system supports

1840

locking without being root. The program drops root privileges as soon

1841

as locked memory is allocated.

1842

.\" created by instant / docbook-to-man, Sun 25 Jun 2006, 13:22