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diff --git a/doc/gpg.texi b/doc/gpg.texi deleted file mode 100644 index aca21a0cb..000000000 --- a/doc/gpg.texi +++ /dev/null @@ -1,2231 +0,0 @@ -\input texinfo -@setfilename gpg.info -@dircategory GnuPG -@direntry -* gpg: (gpg). GnuPG encryption and signing tool. -@end direntry - -@node Top, , , (dir) -@top gpg -@chapheading Name - -gpg --- encryption and signing tool -@chapheading Synopsis - -@example -gpg - --homedir name - --options file - options - command - args - -@end example -@chapheading DESCRIPTION - -@code{gpg} is the main program for the GnuPG system. - -This man page only lists the commands and options available. For more -verbose documentation get the GNU Privacy Handbook (GPH) or one of the -other documents at http://www.gnupg.org/documentation/ . - -Please remember that option parsing stops as soon as a non option is -encountered, you can explicitly stop option parsing by using the -special option "--". -@chapheading COMMANDS - -@code{gpg} may be run with no commands, in which case it will -perform a reasonable action depending on the type of file it is given -as input (an encrypted message is decrypted, a signature is verified, -a file containing keys is listed). - -@code{gpg} recognizes these commands: - -@table @asis - -@item -s, --sign -Make a signature. This command may be combined with --encrypt (for a -signed and encrypted message), --symmetric (for a signed and -symmetrically encrypted message), or --encrypt and --symmetric -together (for a signed message that may be decrypted via a secret key -or a passphrase). - -@item --clearsign -Make a clear text signature. The content in a clear text signature is -readable without any special software. OpenPGP software is only -needed to verify the signature. Clear text signatures may modify -end-of-line whitespace for platform independence and are not intended -to be reversible. - -@item -b, --detach-sign -Make a detached signature. - -@item -e, --encrypt -Encrypt data. This option may be combined with --sign (for a signed -and encrypted message), --symmetric (for a message that may be -decrypted via a secret key or a passphrase), or --sign and --symmetric -together (for a signed message that may be decrypted via a secret key -or a passphrase). - -@item -c, --symmetric -Encrypt with a symmetric cipher using a passphrase. The default -symmetric cipher used is CAST5, but may be chosen with the ---cipher-algo option. This option may be combined with --sign (for a -signed and symmetrically encrypted message), --encrypt (for a message -that may be decrypted via a secret key or a passphrase), or --sign and ---encrypt together (for a signed message that may be decrypted via a -secret key or a passphrase). - -@item --store -Store only (make a simple RFC1991 packet). - -@item -d, --decrypt -Decrypt @code{file} (or stdin if no file is specified) and -write it to stdout (or the file specified with ---output). If the decrypted file is signed, the -signature is also verified. This command differs -from the default operation, as it never writes to the -filename which is included in the file and it -rejects files which don't begin with an encrypted -message. - -@item --verify -Assume that @code{sigfile} is a signature and verify it -without generating any output. With no arguments, -the signature packet is read from stdin. If -only a sigfile is given, it may be a complete -signature or a detached signature, in which case -the signed stuff is expected in a file without the -".sig" or ".asc" extension. -With more than -1 argument, the first should be a detached signature -and the remaining files are the signed stuff. To read the signed -stuff from stdin, use @samp{-} as the second filename. -For security reasons a detached signature cannot read the signed -material from stdin without denoting it in the above way. - -@item --multifile -This modifies certain other commands to accept multiple files for -processing on the command line or read from stdin with each filename -on a separate line. This allows for many files to be processed at -once. --multifile may currently be used along with --verify, ---encrypt, and --decrypt. Note that `--multifile --verify' may not be -used with detached signatures. - -@item --verify-files -Identical to `--multifile --verify'. - -@item --encrypt-files -Identical to `--multifile --encrypt'. - -@item --decrypt-files -Identical to `--multifile --decrypt'. - -@item --list-keys -@itemx --list-public-keys -List all keys from the public keyrings, or just the ones given on the -command line. - -Avoid using the output of this command in scripts or other programs as -it is likely to change as GnuPG changes. See --with-colons for a -machine-parseable key listing command that is appropriate for use in -scripts and other programs. - -@item -K, --list-secret-keys -List all keys from the secret keyrings, or just the ones given on the -command line. A '#' after the letters 'sec' means that the secret key -is not usable (for example, if it was created via ---export-secret-subkeys). - -@item --list-sigs -Same as --list-keys, but the signatures are listed too. - -For each signature listed, there are several flags in between the -"sig" tag and keyid. These flags give additional information about -each signature. From left to right, they are the numbers 1-3 for -certificate check level (see --ask-cert-level), "L" for a local or -non-exportable signature (see --lsign-key), "R" for a nonRevocable -signature (see the --edit-key command "nrsign"), "P" for a signature -that contains a policy URL (see --cert-policy-url), "N" for a -signature that contains a notation (see --cert-notation), "X" for an -eXpired signature (see --ask-cert-expire), and the numbers 1-9 or "T" -for 10 and above to indicate trust signature levels (see the ---edit-key command "tsign"). - -@item --check-sigs -Same as --list-sigs, but the signatures are verified. - -@item --fingerprint -List all keys with their fingerprints. This is the -same output as --list-keys but with the additional output -of a line with the fingerprint. May also be combined -with --list-sigs or --check-sigs. -If this command is given twice, the fingerprints of all -secondary keys are listed too. - -@item --list-packets -List only the sequence of packets. This is mainly -useful for debugging. - -@item --gen-key -Generate a new key pair. This command is normally only used -interactively. - -There is an experimental feature which allows you to create keys -in batch mode. See the file @file{doc/DETAILS} -in the source distribution on how to use this. - -@item --edit-key @code{name} -Present a menu which enables you to do all key -related tasks: - -@table @asis - -@item sign -Make a signature on key of user @code{name} If the key is not yet -signed by the default user (or the users given with -u), the program -displays the information of the key again, together with its -fingerprint and asks whether it should be signed. This question is -repeated for all users specified with --u. - -@item lsign -Same as "sign" but the signature is marked as non-exportable and will -therefore never be used by others. This may be used to make keys -valid only in the local environment. - -@item nrsign -Same as "sign" but the signature is marked as non-revocable and can -therefore never be revoked. - -@item tsign -Make a trust signature. This is a signature that combines the notions -of certification (like a regular signature), and trust (like the -"trust" command). It is generally only useful in distinct communities -or groups. -@end table - -Note that "l" (for local / non-exportable), "nr" (for non-revocable, -and "t" (for trust) may be freely mixed and prefixed to "sign" to -create a signature of any type desired. - -@table @asis - -@item revsig -Revoke a signature. For every signature which has been generated by -one of the secret keys, GnuPG asks whether a revocation certificate -should be generated. - -@item trust -Change the owner trust value. This updates the -trust-db immediately and no save is required. - -@item disable -@itemx enable -Disable or enable an entire key. A disabled key can not normally be -used for encryption. - -@item adduid -Create an alternate user id. - -@item addphoto -Create a photographic user id. This will prompt for a JPEG file that -will be embedded into the user ID. Note that a very large JPEG will -make for a very large key. Also note that some programs will display -your JPEG unchanged (GnuPG), and some programs will scale it to fit in -a dialog box (PGP). - -@item deluid -Delete a user id. - -@item delsig -Delete a signature. - -@item revuid -Revoke a user id. - -@item addkey -Add a subkey to this key. - -@item addcardkey -Generate a key on a card and add it -to this key. - -@item keytocard -Transfer the selected secret key (or the primary key if no key has -been selected) to a smartcard. The secret key in the keyring will be -replaced by a stub if the key could be stored successfully on the card -and you use the save command later. Only certain key types may be -transferred to the card. A sub menu allows you to select on what card -to store the key. Note that it is not possible to get that key back -from the card - if the card gets broken your secret key will be lost -unless you have a backup somewhere. - -@item bkuptocard @code{file} -Restore the given file to a card. This command -may be used to restore a backup key (as generated during card -initialization) to a new card. In almost all cases this will be the -encryption key. You should use this command only -with the corresponding public key and make sure that the file -given as argument is indeed the backup to restore. You should -then select 2 to restore as encryption key. -You will first be asked to enter the passphrase of the backup key and -then for the Admin PIN of the card. - -@item delkey -Remove a subkey. - -@item addrevoker -Add a designated revoker. This takes one optional argument: -"sensitive". If a designated revoker is marked as sensitive, it will -not be exported by default (see -export-options). - -@item revkey -Revoke a subkey. - -@item expire -Change the key expiration time. If a subkey is selected, the -expiration time of this subkey will be changed. With no selection, -the key expiration of the primary key is changed. - -@item passwd -Change the passphrase of the secret key. - -@item primary -Flag the current user id as the primary one, removes the primary user -id flag from all other user ids and sets the timestamp of all affected -self-signatures one second ahead. Note that setting a photo user ID -as primary makes it primary over other photo user IDs, and setting a -regular user ID as primary makes it primary over other regular user -IDs. - -@item uid @code{n} -Toggle selection of user id with index @code{n}. -Use 0 to deselect all. - -@item key @code{n} -Toggle selection of subkey with index @code{n}. -Use 0 to deselect all. - -@item check -Check all selected user ids. - -@item showphoto -Display the selected photographic user -id. - -@item pref -List preferences from the selected user ID. This shows the actual -preferences, without including any implied preferences. - -@item showpref -More verbose preferences listing for the selected user ID. This shows -the preferences in effect by including the implied preferences of 3DES -(cipher), SHA-1 (digest), and Uncompressed (compression) if they are -not already included in the preference list. In addition, the -preferred keyserver and signature notations (if any) are shown. - -@item setpref @code{string} -Set the list of user ID preferences to @code{string} for all (or just -the selected) user IDs. Calling setpref with no arguments sets the -preference list to the default (either built-in or set via ---default-preference-list), and calling setpref with "none" as the -argument sets an empty preference list. Use "gpg --version" to get a -list of available algorithms. Note that while you can change the -preferences on an attribute user ID (aka "photo ID"), GnuPG does not -select keys via attribute user IDs so these preferences will not be -used by GnuPG. - -@item keyserver -Set a preferred keyserver for the specified user ID(s). This allows -other users to know where you prefer they get your key from. See ---keyserver-options honor-keyserver-url for more on how this works. -Setting a value of "none" removes an existing preferred keyserver. - -@item notation -Set a name=value notation for the specified user ID(s). See ---cert-notation for more on how this works. Setting a value of "none" -removes all notations, setting a notation prefixed with a minus sign -(-) removes that notation, and setting a notation name (without the -=value) prefixed with a minus sign removes all notations with that -name. - -@item toggle -Toggle between public and secret key listing. - -@item clean -Compact (by removing all signatures except the selfsig) any user ID -that is no longer usable (e.g. revoked, or expired). Then, remove any -signatures that are not usable by the trust calculations. -Specifically, this removes any signature that does not validate, any -signature that is superseded by a later signature, revoked signatures, -and signatures issued by keys that are not present on the keyring. - -@item minimize -Make the key as small as possible. This removes all signatures from -each user ID except for the most recent self-signature. - -@item cross-certify -Add cross-certification signatures to signing subkeys that may not -currently have them. Cross-certification signatures protect against a -subtle attack against signing subkeys. See ---require-cross-certification. - -@item save -Save all changes to the key rings and quit. - -@item quit -Quit the program without updating the -key rings. -@end table - -The listing shows you the key with its secondary -keys and all user ids. Selected keys or user ids -are indicated by an asterisk. The trust value is -displayed with the primary key: the first is the -assigned owner trust and the second is the calculated -trust value. Letters are used for the values: - -@table @asis - -@item - -No ownertrust assigned / not yet calculated. - -@item e -Trust -calculation has failed; probably due to an expired key. - -@item q -Not enough information for calculation. - -@item n -Never trust this key. - -@item m -Marginally trusted. - -@item f -Fully trusted. - -@item u -Ultimately trusted. -@end table - -@item --card-edit -Present a menu to work with a smartcard. The subcommand "help" provides -an overview on available commands. For a detailed description, please -see the Card HOWTO at -http://www.gnupg.org/documentation/howtos.html#GnuPG-cardHOWTO . - -@item --card-status -Show the content of the smart card. - -@item --change-pin -Present a menu to allow changing the PIN of a smartcard. This -functionality is also available as the subcommand "passwd" with the ---card-edit command. - -@item --sign-key @code{name} -Signs a public key with your secret key. This is a shortcut version of -the subcommand "sign" from --edit. - -@item --lsign-key @code{name} -Signs a public key with your secret key but marks it as -non-exportable. This is a shortcut version of the subcommand "lsign" -from --edit. - -@item --delete-key @code{name} -Remove key from the public keyring. In batch mode either --yes is -required or the key must be specified by fingerprint. This is a -safeguard against accidental deletion of multiple keys. - -@item --delete-secret-key @code{name} -Remove key from the secret and public keyring. In batch mode the key -must be specified by fingerprint. - -@item --delete-secret-and-public-key @code{name} -Same as --delete-key, but if a secret key exists, it will be removed -first. In batch mode the key must be specified by fingerprint. - -@item --gen-revoke @code{name} -Generate a revocation certificate for the complete key. To revoke -a subkey or a signature, use the --edit command. - -@item --desig-revoke @code{name} -Generate a designated revocation certificate for a key. This allows a -user (with the permission of the keyholder) to revoke someone else's -key. - -@item --export -Either export all keys from all keyrings (default -keyrings and those registered via option --keyring), -or if at least one name is given, those of the given -name. The new keyring is written to stdout or to -the file given with option "output". Use together -with --armor to mail those keys. - -@item --send-keys -Same as --export but sends the keys to a keyserver. -Option --keyserver must be used to give the name -of this keyserver. Don't send your complete keyring -to a keyserver - select only those keys which are new -or changed by you. - -@item --export-secret-keys -@itemx --export-secret-subkeys -Same as --export, but exports the secret keys instead. -This is normally not very useful and a security risk. -The second form of the command has the special property to -render the secret part of the primary key useless; this is -a GNU extension to OpenPGP and other implementations can -not be expected to successfully import such a key. -See the option --simple-sk-checksum if you want to import such an -exported key with an older OpenPGP implementation. - -@item --import -@itemx --fast-import -Import/merge keys. This adds the given keys to the -keyring. The fast version is currently just a synonym. - -There are a few other options which control how this command works. -Most notable here is the --keyserver-options merge-only option which -does not insert new keys but does only the merging of new signatures, -user-IDs and subkeys. - -@item --recv-keys @code{key IDs} -Import the keys with the given key IDs from a keyserver. Option ---keyserver must be used to give the name of this keyserver. - -@item --refresh-keys -Request updates from a keyserver for keys that already exist on the -local keyring. This is useful for updating a key with the latest -signatures, user IDs, etc. Calling this with no arguments will -refresh the entire keyring. Option --keyserver must be used to give -the name of the keyserver for all keys that do not have preferred -keyservers set (see --keyserver-options honor-keyserver-url). - -@item --search-keys @code{names} -Search the keyserver for the given names. Multiple names given here -will be joined together to create the search string for the keyserver. -Option --keyserver must be used to give the name of this keyserver. -Keyservers that support different search methods allow using the -syntax specified in "How to specify a user ID" below. Note that -different keyserver types support different search methods. Currently -only LDAP supports them all. - -@item --fetch-keys @code{URIs} -Retrieve keys located at the specified URIs. Note that different -installations of GnuPG may support different protocols (HTTP, FTP, -LDAP, etc.) - -@item --update-trustdb -Do trust database maintenance. This command iterates over all keys -and builds the Web of Trust. This is an interactive command because it -may have to ask for the "ownertrust" values for keys. The user has to -give an estimation of how far she trusts the owner of the displayed -key to correctly certify (sign) other keys. GnuPG only asks for the -ownertrust value if it has not yet been assigned to a key. Using the ---edit-key menu, the assigned value can be changed at any time. - -@item --check-trustdb -Do trust database maintenance without user interaction. From time to -time the trust database must be updated so that expired keys or -signatures and the resulting changes in the Web of Trust can be -tracked. Normally, GnuPG will calculate when this is required and do -it automatically unless --no-auto-check-trustdb is set. This command -can be used to force a trust database check at any time. The -processing is identical to that of --update-trustdb but it skips keys -with a not yet defined "ownertrust". - -For use with cron jobs, this command can be used together with --batch -in which case the trust database check is done only if a check is -needed. To force a run even in batch mode add the option --yes. - -@item --export-ownertrust -Send the ownertrust values to stdout. This is useful for backup -purposes as these values are the only ones which can't be re-created -from a corrupted trust DB. - -@item --import-ownertrust -Update the trustdb with the ownertrust values stored -in @code{files} (or stdin if not given); existing -values will be overwritten. - -@item --rebuild-keydb-caches -When updating from version 1.0.6 to 1.0.7 this command should be used -to create signature caches in the keyring. It might be handy in other -situations too. - -@item --print-md @code{algo} -@itemx --print-mds -Print message digest of algorithm ALGO for all given files or stdin. -With the second form (or a deprecated "*" as algo) digests for all -available algorithms are printed. - -@item --gen-random @code{0|1|2} -Emit COUNT random bytes of the given quality level. If count is not given -or zero, an endless sequence of random bytes will be emitted. -PLEASE, don't use this command unless you know what you are doing; it may -remove precious entropy from the system! - -@item --gen-prime @code{mode} @code{bits} -Use the source, Luke :-). The output format is still subject to change. - -@item --version -Print version information along with a list -of supported algorithms. - -@item --warranty -Print warranty information. - -@item -h, --help -Print usage information. This is a really long list even though it -doesn't list all options. For every option, consult this manual. -@end table -@chapheading OPTIONS - -Long options can be put in an options file (default -"~/.gnupg/gpg.conf"). Short option names will not work - for example, -"armor" is a valid option for the options file, while "a" is not. Do -not write the 2 dashes, but simply the name of the option and any -required arguments. Lines with a hash ('#') as the first -non-white-space character are ignored. Commands may be put in this -file too, but that is not generally useful as the command will execute -automatically with every execution of gpg. - -@code{gpg} recognizes these options: - -@table @asis - -@item -a, --armor -Create ASCII armored output. - -@item -o, --output @code{file} -Write output to @code{file}. - -@item --max-output @code{n} -This option sets a limit on the number of bytes that will be generated -when processing a file. Since OpenPGP supports various levels of -compression, it is possible that the plaintext of a given message may -be significantly larger than the original OpenPGP message. While -GnuPG works properly with such messages, there is often a desire to -set a maximum file size that will be generated before processing is -forced to stop by the OS limits. Defaults to 0, which means "no -limit". - -@item --mangle-dos-filenames -@itemx --no-mangle-dos-filenames -Older version of Windows cannot handle filenames with more than one -dot. --mangle-dos-filenames causes GnuPG to replace (rather than add -to) the extension of an output filename to avoid this problem. This -option is off by default and has no effect on non-Windows platforms. - -@item -u, --local-user @code{name} -Use @code{name} as the key to sign with. Note that this option -overrides --default-key. - -@item --default-key @code{name} -Use @code{name} as the default key to sign with. If this option is not -used, the default key is the first key found in the secret keyring. -Note that -u or --local-user overrides this option. - -@item -r, --recipient @code{name} -Encrypt for user id @code{name}. If this option or --hidden-recipient -is not specified, GnuPG asks for the user-id unless ---default-recipient is given. - -@item -R, --hidden-recipient @code{name} -Encrypt for user ID @code{name}, but hide the key ID of this user's -key. This option helps to hide the receiver of the message and is a -limited countermeasure against traffic analysis. If this option or ---recipient is not specified, GnuPG asks for the user ID unless ---default-recipient is given. - -@item --default-recipient @code{name} -Use @code{name} as default recipient if option --recipient is not used and -don't ask if this is a valid one. @code{name} must be non-empty. - -@item --default-recipient-self -Use the default key as default recipient if option --recipient is not used and -don't ask if this is a valid one. The default key is the first one from the -secret keyring or the one set with --default-key. - -@item --no-default-recipient -Reset --default-recipient and --default-recipient-self. - -@item --encrypt-to @code{name} -Same as --recipient but this one is intended for use -in the options file and may be used with -your own user-id as an "encrypt-to-self". These keys -are only used when there are other recipients given -either by use of --recipient or by the asked user id. -No trust checking is performed for these user ids and -even disabled keys can be used. - -@item --hidden-encrypt-to @code{name} -Same as --hidden-recipient but this one is intended for use in the -options file and may be used with your own user-id as a hidden -"encrypt-to-self". These keys are only used when there are other -recipients given either by use of --recipient or by the asked user id. -No trust checking is performed for these user ids and even disabled -keys can be used. - -@item --no-encrypt-to -Disable the use of all --encrypt-to and --hidden-encrypt-to keys. - -@item -v, --verbose -Give more information during processing. If used -twice, the input data is listed in detail. - -@item -q, --quiet -Try to be as quiet as possible. - -@item -z @code{n} -@itemx --compress-level @code{n} -@itemx --bzip2-compress-level @code{n} -Set compression level to @code{n} for the ZIP and ZLIB compression -algorithms. The default is to use the default compression level of -zlib (normally 6). --bzip2-compress-level sets the compression level -for the BZIP2 compression algorithm (defaulting to 6 as well). This -is a different option from --compress-level since BZIP2 uses a -significant amount of memory for each additional compression level. --z sets both. A value of 0 for @code{n} disables compression. - -@item --bzip2-decompress-lowmem -Use a different decompression method for BZIP2 compressed files. This -alternate method uses a bit more than half the memory, but also runs -at half the speed. This is useful under extreme low memory -circumstances when the file was originally compressed at a high ---bzip2-compress-level. - -@item -t, --textmode -@itemx --no-textmode -Treat input files as text and store them in the OpenPGP canonical text -form with standard "CRLF" line endings. This also sets the necessary -flags to inform the recipient that the encrypted or signed data is -text and may need its line endings converted back to whatever the -local system uses. This option is useful when communicating between -two platforms that have different line ending conventions (UNIX-like -to Mac, Mac to Windows, etc). --no-textmode disables this option, and -is the default. - -If -t (but not --textmode) is used together with armoring and signing, -this enables clearsigned messages. This kludge is needed for -command-line compatibility with command-line versions of PGP; normally -you would use --sign or --clearsign to select the type of the -signature. - -@item -n, --dry-run -Don't make any changes (this is not completely implemented). - -@item -i, --interactive -Prompt before overwriting any files. - -@item --batch -@itemx --no-batch -Use batch mode. Never ask, do not allow interactive commands. ---no-batch disables this option. - -@item --no-tty -Make sure that the TTY (terminal) is never used for any output. -This option is needed in some cases because GnuPG sometimes prints -warnings to the TTY if --batch is used. - -@item --yes -Assume "yes" on most questions. - -@item --no -Assume "no" on most questions. - -@item --ask-cert-level -@itemx --no-ask-cert-level -When making a key signature, prompt for a certification level. If -this option is not specified, the certification level used is set via ---default-cert-level. See --default-cert-level for information on the -specific levels and how they are used. --no-ask-cert-level disables -this option. This option defaults to no. - -@item --default-cert-level @code{n} -The default to use for the check level when signing a key. - -0 means you make no particular claim as to how carefully you verified -the key. - -1 means you believe the key is owned by the person who claims to own -it but you could not, or did not verify the key at all. This is -useful for a "persona" verification, where you sign the key of a -pseudonymous user. - -2 means you did casual verification of the key. For example, this -could mean that you verified that the key fingerprint and checked the -user ID on the key against a photo ID. - -3 means you did extensive verification of the key. For example, this -could mean that you verified the key fingerprint with the owner of the -key in person, and that you checked, by means of a hard to forge -document with a photo ID (such as a passport) that the name of the key -owner matches the name in the user ID on the key, and finally that you -verified (by exchange of email) that the email address on the key -belongs to the key owner. - -Note that the examples given above for levels 2 and 3 are just that: -examples. In the end, it is up to you to decide just what "casual" -and "extensive" mean to you. - -This option defaults to 0 (no particular claim). - -@item --min-cert-level -When building the trust database, treat any signatures with a -certification level below this as invalid. Defaults to 2, which -disregards level 1 signatures. Note that level 0 "no particular -claim" signatures are always accepted. - -@item --trusted-key @code{long key ID} -Assume that the specified key (which must be given -as a full 8 byte key ID) is as trustworthy as one of -your own secret keys. This option is useful if you -don't want to keep your secret keys (or one of them) -online but still want to be able to check the validity of a given -recipient's or signator's key. - -@item --trust-model @code{pgp|classic|direct|always|auto} -Set what trust model GnuPG should follow. The models are: - -@table @asis - -@item pgp -This is the Web of Trust combined with trust signatures as used in PGP -5.x and later. This is the default trust model when creating a new -trust database. - -@item classic -This is the standard Web of Trust as used in PGP 2.x and earlier. - -@item direct -Key validity is set directly by the user and not calculated via the -Web of Trust. - -@item always -Skip key validation and assume that used keys are always fully -trusted. You generally won't use this unless you are using some -external validation scheme. This option also suppresses the -"[uncertain]" tag printed with signature checks when there is no -evidence that the user ID is bound to the key. - -@item auto -Select the trust model depending on whatever the internal trust -database says. This is the default model if such a database already -exists. -@end table - -@item --always-trust -Identical to `--trust-model always'. This option is deprecated. - -@item --auto-key-locate @code{parameters} -@itemx --no-auto-key-locate -GnuPG can automatically locate and retrieve keys as needed using this -option. This happens when encrypting to an email address (in the -"user@@example.com" form), and there are no user@@example.com keys on -the local keyring. This option takes any number of the following -arguments, in the order they are to be tried: - -@table @asis - -@item cert -locate a key using DNS CERT, as specified in 2538bis (currently in -draft): http://www.josefsson.org/rfc2538bis/ - -@item pka -locate a key using DNS PKA. - -@item ldap -locate a key using the PGP Universal method of checking -"ldap://keys.(thedomain)". - -@item keyserver -locate a key using whatever keyserver is defined using the --keyserver -option. - -@item (keyserver URL) -In addition, a keyserver URL as used in the --keyserver option may be -used here to query that particular keyserver. -@end table - -@item --keyid-format @code{short|0xshort|long|0xlong} -Select how to display key IDs. "short" is the traditional 8-character -key ID. "long" is the more accurate (but less convenient) -16-character key ID. Add an "0x" to either to include an "0x" at the -beginning of the key ID, as in 0x99242560. - -@item --keyserver @code{name} -Use @code{name} as your keyserver. This is the server that ---recv-keys, --send-keys, and --search-keys will communicate with to -receive keys from, send keys to, and search for keys on. The format -of the @code{name} is a URI: `scheme:[//]keyservername[:port]' The -scheme is the type of keyserver: "hkp" for the HTTP (or compatible) -keyservers, "ldap" for the LDAP keyservers, or "mailto" for the Graff -email keyserver. Note that your particular installation of GnuPG may -have other keyserver types available as well. Keyserver schemes are -case-insensitive. After the keyserver name, optional keyserver -configuration options may be provided. These are the same as the -global --keyserver-options from below, but apply only to this -particular keyserver. - -Most keyservers synchronize with each other, so there is generally no -need to send keys to more than one server. The keyserver -"hkp://subkeys.pgp.net" uses round robin DNS to give a different -keyserver each time you use it. - -@item --keyserver-options @code{name=value1 } -This is a space or comma delimited string that gives options for the -keyserver. Options can be prepended with a `no-' to give the opposite -meaning. Valid import-options or export-options may be used here as -well to apply to importing (--recv-key) or exporting (--send-key) a -key from a keyserver. While not all options are available for all -keyserver types, some common options are: - -@table @asis - -@item include-revoked -When searching for a key with --search-keys, include keys that are -marked on the keyserver as revoked. Note that not all keyservers -differentiate between revoked and unrevoked keys, and for such -keyservers this option is meaningless. Note also that most keyservers -do not have cryptographic verification of key revocations, and so -turning this option off may result in skipping keys that are -incorrectly marked as revoked. - -@item include-disabled -When searching for a key with --search-keys, include keys that are -marked on the keyserver as disabled. Note that this option is not -used with HKP keyservers. - -@item auto-key-retrieve -This option enables the automatic retrieving of keys from a keyserver -when verifying signatures made by keys that are not on the local -keyring. - -Note that this option makes a "web bug" like behavior possible. -Keyserver operators can see which keys you request, so by sending you -a message signed by a brand new key (which you naturally will not have -on your local keyring), the operator can tell both your IP address and -the time when you verified the signature. - -@item honor-keyserver-url -When using --refresh-keys, if the key in question has a preferred -keyserver URL, then use that preferred keyserver to refresh the key -from. In addition, if auto-key-retrieve is set, and the signature -being verified has a preferred keyserver URL, then use that preferred -keyserver to fetch the key from. Defaults to yes. - -@item honor-pka-record -If auto-key-retrieve is set, and the signature being verified has a -PKA record, then use the PKA information to fetch the key. Defaults -to yes. - -@item include-subkeys -When receiving a key, include subkeys as potential targets. Note that -this option is not used with HKP keyservers, as they do not support -retrieving keys by subkey id. - -@item use-temp-files -On most Unix-like platforms, GnuPG communicates with the keyserver -helper program via pipes, which is the most efficient method. This -option forces GnuPG to use temporary files to communicate. On some -platforms (such as Win32 and RISC OS), this option is always enabled. - -@item keep-temp-files -If using `use-temp-files', do not delete the temp files after using -them. This option is useful to learn the keyserver communication -protocol by reading the temporary files. - -@item verbose -Tell the keyserver helper program to be more verbose. This option can -be repeated multiple times to increase the verbosity level. - -@item timeout -Tell the keyserver helper program how long (in seconds) to try and -perform a keyserver action before giving up. Note that performing -multiple actions at the same time uses this timeout value per action. -For example, when retrieving multiple keys via --recv-keys, the -timeout applies separately to each key retrieval, and not to the ---recv-keys command as a whole. Defaults to 30 seconds. - -@item http-proxy -For HTTP-like keyserver schemes that (such as HKP and HTTP itself), -try to access the keyserver over a proxy. If a @code{value} is -specified, use this as the HTTP proxy. If no @code{value} is -specified, the value of the environment variable "http_proxy", if any, -will be used. - -@item max-cert-size -When retrieving a key via DNS CERT, only accept keys up to this size. -Defaults to 16384 bytes. -@end table - -@item --import-options @code{parameters} -This is a space or comma delimited string that gives options for -importing keys. Options can be prepended with a `no-' to give the -opposite meaning. The options are: - -@table @asis - -@item import-local-sigs -Allow importing key signatures marked as "local". This is not -generally useful unless a shared keyring scheme is being used. -Defaults to no. - -@item repair-pks-subkey-bug -During import, attempt to repair the damage caused by the PKS -keyserver bug (pre version 0.9.6) that mangles keys with multiple -subkeys. Note that this cannot completely repair the damaged key as -some crucial data is removed by the keyserver, but it does at least -give you back one subkey. Defaults to no for regular --import and to -yes for keyserver --recv-keys. - -@item merge-only -During import, allow key updates to existing keys, but do not allow -any new keys to be imported. Defaults to no. - -@item import-clean -After import, compact (remove all signatures except the -self-signature) any user IDs from the new key that are not usable. -Then, remove any signatures from the new key that are not usable. -This includes signatures that were issued by keys that are not present -on the keyring. This option is the same as running the --edit-key -command "clean" after import. Defaults to no. - -@item import-minimal -Import the smallest key possible. This removes all signatures except -the most recent self-signature on each user ID. This option is the -same as running the --edit-key command "minimize" after import. -Defaults to no. -@end table - -@item --export-options @code{parameters} -This is a space or comma delimited string that gives options for -exporting keys. Options can be prepended with a `no-' to give the -opposite meaning. The options are: - -@table @asis - -@item export-local-sigs -Allow exporting key signatures marked as "local". This is not -generally useful unless a shared keyring scheme is being used. -Defaults to no. - -@item export-attributes -Include attribute user IDs (photo IDs) while exporting. This is -useful to export keys if they are going to be used by an OpenPGP -program that does not accept attribute user IDs. Defaults to yes. - -@item export-sensitive-revkeys -Include designated revoker information that was marked as -"sensitive". Defaults to no. - -@item export-reset-subkey-passwd -When using the "--export-secret-subkeys" command, this option resets -the passphrases for all exported subkeys to empty. This is useful -when the exported subkey is to be used on an unattended machine where -a passphrase doesn't necessarily make sense. Defaults to no. - -@item export-clean -Compact (remove all signatures from) user IDs on the key being -exported if the user IDs are not usable. Also, do not export any -signatures that are not usable. This includes signatures that were -issued by keys that are not present on the keyring. This option is -the same as running the --edit-key command "clean" before export -except that the local copy of the key is not modified. Defaults to -no. - -@item export-minimal -Export the smallest key possible. This removes all signatures except -the most recent self-signature on each user ID. This option is the -same as running the --edit-key command "minimize" before export except -that the local copy of the key is not modified. Defaults to no. -@end table - -@item --list-options @code{parameters} -This is a space or comma delimited string that gives options used when -listing keys and signatures (that is, --list-keys, --list-sigs, ---list-public-keys, --list-secret-keys, and the --edit-key functions). -Options can be prepended with a `no-' to give the opposite meaning. -The options are: - -@table @asis - -@item show-photos -Causes --list-keys, --list-sigs, --list-public-keys, and ---list-secret-keys to display any photo IDs attached to the key. -Defaults to no. See also --photo-viewer. - -@item show-policy-urls -Show policy URLs in the --list-sigs or --check-sigs listings. -Defaults to no. - -@item show-notations -@itemx show-std-notations -@itemx show-user-notations -Show all, IETF standard, or user-defined signature notations in the ---list-sigs or --check-sigs listings. Defaults to no. - -@item show-keyserver-urls -Show any preferred keyserver URL in the --list-sigs or --check-sigs -listings. Defaults to no. - -@item show-uid-validity -Display the calculated validity of user IDs during key listings. -Defaults to no. - -@item show-unusable-uids -Show revoked and expired user IDs in key listings. Defaults to no. - -@item show-unusable-subkeys -Show revoked and expired subkeys in key listings. Defaults to no. - -@item show-keyring -Display the keyring name at the head of key listings to show which -keyring a given key resides on. Defaults to no. - -@item show-sig-expire -Show signature expiration dates (if any) during --list-sigs or ---check-sigs listings. Defaults to no. - -@item show-sig-subpackets -Include signature subpackets in the key listing. This option can take -an optional argument list of the subpackets to list. If no argument -is passed, list all subpackets. Defaults to no. This option is only -meaningful when using --with-colons along with --list-sigs or ---check-sigs. -@end table - -@item --verify-options @code{parameters} -This is a space or comma delimited string that gives options used when -verifying signatures. Options can be prepended with a `no-' to give -the opposite meaning. The options are: - -@table @asis - -@item show-photos -Display any photo IDs present on the key that issued the signature. -Defaults to no. See also --photo-viewer. - -@item show-policy-urls -Show policy URLs in the signature being verified. Defaults to no. - -@item show-notations -@itemx show-std-notations -@itemx show-user-notations -Show all, IETF standard, or user-defined signature notations in the -signature being verified. Defaults to IETF standard. - -@item show-keyserver-urls -Show any preferred keyserver URL in the signature being verified. -Defaults to no. - -@item show-uid-validity -Display the calculated validity of the user IDs on the key that issued -the signature. Defaults to no. - -@item show-unusable-uids -Show revoked and expired user IDs during signature verification. -Defaults to no. - -@item pka-lookups -Enable PKA lookups to verify sender addresses. Note that PKA is based -on DNS, and so enabling this option may disclose information on when -and what signatures are verified or to whom data is encrypted. This -is similar to the "web bug" described for the auto-key-retrieve -feature. - -@item pka-trust-increase -Raise the trust in a signature to full if the signature passes PKA -validation. This option is only meaningful if pka-lookups is set. -@end table - -@item --enable-dsa2 -@itemx --disable-dsa2 -Enables new-style DSA keys which (unlike the old style) may be larger -than 1024 bit and use hashes other than SHA-1 and RIPEMD/160. Note -that very few programs currently support these keys and signatures -from them. - -@item --show-photos -@itemx --no-show-photos -Causes --list-keys, --list-sigs, --list-public-keys, ---list-secret-keys, and verifying a signature to also display the -photo ID attached to the key, if any. See also --photo-viewer. These -options are deprecated. Use `--list-options [no-]show-photos' and/or -`--verify-options [no-]show-photos' instead. - -@item --photo-viewer @code{string} -This is the command line that should be run to view a photo ID. "%i" -will be expanded to a filename containing the photo. "%I" does the -same, except the file will not be deleted once the viewer exits. -Other flags are "%k" for the key ID, "%K" for the long key ID, "%f" -for the key fingerprint, "%t" for the extension of the image type -(e.g. "jpg"), "%T" for the MIME type of the image (e.g. "image/jpeg"), -and "%%" for an actual percent sign. If neither %i or %I are present, -then the photo will be supplied to the viewer on standard input. - -The default viewer is "xloadimage -fork -quiet -title 'KeyID 0x%k' -stdin". Note that if your image viewer program is not secure, then -executing it from GnuPG does not make it secure. - -@item --exec-path @code{string} -Sets a list of directories to search for photo viewers and keyserver -helpers. If not provided, keyserver helpers use the compiled-in -default directory, and photo viewers use the $PATH environment -variable. -Note, that on W32 system this value is ignored when searching for -keyserver helpers. - -@item --show-keyring -Display the keyring name at the head of key listings to show which -keyring a given key resides on. This option is deprecated: use -`--list-options [no-]show-keyring' instead. - -@item --keyring @code{file} -Add @code{file} to the current list of keyrings. If @code{file} begins -with a tilde and a slash, these are replaced by the $HOME -directory. If the filename does not contain a slash, it is assumed to -be in the GnuPG home directory ("~/.gnupg" if --homedir or $GNUPGHOME -is not used). - -Note that this adds a keyring to the current list. If the intent is -to use the specified keyring alone, use --keyring along with ---no-default-keyring. - -@item --secret-keyring @code{file} -Same as --keyring but for the secret keyrings. - -@item --primary-keyring @code{file} -Designate @code{file} as the primary public keyring. This means that -newly imported keys (via --import or keyserver --recv-from) will go to -this keyring. - -@item --trustdb-name @code{file} -Use @code{file} instead of the default trustdb. If @code{file} begins -with a tilde and a slash, these are replaced by the $HOME -directory. If the filename does not contain a slash, it is assumed to -be in the GnuPG home directory ("~/.gnupg" if --homedir or $GNUPGHOME -is not used). - -@item --homedir @code{directory} -Set the name of the home directory to @code{directory} If this option is not -used it defaults to "~/.gnupg". It does not make sense to use this in -a options file. This also overrides the environment variable -$GNUPGHOME. - -@item --pcsc-driver @code{file} -Use @code{file} to access the smartcard reader. The current default is -`libpcsclite.so.1' for GLIBC based systems, -`/System/Library/Frameworks/PCSC.framework/PCSC' for MAC OS X, -`winscard.dll' for Windows and `libpcsclite.so' for other systems. - -@item --ctapi-driver @code{file} -Use @code{file} to access the smartcard reader. The current default -is `libtowitoko.so'. Note that the use of this interface is -deprecated; it may be removed in future releases. - -@item --disable-ccid -Disable the integrated support for CCID compliant readers. This -allows to fall back to one of the other drivers even if the internal -CCID driver can handle the reader. Note, that CCID support is only -available if libusb was available at build time. - -@item --reader-port @code{number_or_string} -This option may be used to specify the port of the card terminal. A -value of 0 refers to the first serial device; add 32768 to access USB -devices. The default is 32768 (first USB device). PC/SC or CCID -readers might need a string here; run the program in verbose mode to get -a list of available readers. The default is then the first reader -found. - -@item --display-charset @code{name} -Set the name of the native character set. This is used to convert -some informational strings like user IDs to the proper UTF-8 encoding. -Note that this has nothing to do with the character set of data to be -encrypted or signed; GnuPG does not recode user supplied data. If -this option is not used, the default character set is determined from -the current locale. A verbosity level of 3 shows the chosen set. -Valid values for @code{name} are: - -@table @asis - -@item iso-8859-1 -This is the Latin 1 set. - -@item iso-8859-2 -The Latin 2 set. - -@item iso-8859-15 -This is currently an alias for -the Latin 1 set. - -@item koi8-r -The usual Russian set (rfc1489). - -@item utf-8 -Bypass all translations and assume -that the OS uses native UTF-8 encoding. -@end table - -@item --utf8-strings -@itemx --no-utf8-strings -Assume that command line arguments are given as UTF8 strings. The -default (--no-utf8-strings) is to assume that arguments are encoded in -the character set as specified by --display-charset. These options -affect all following arguments. Both options may be used multiple -times. - -@item --options @code{file} -Read options from @code{file} and do not try to read -them from the default options file in the homedir -(see --homedir). This option is ignored if used -in an options file. - -@item --no-options -Shortcut for "--options /dev/null". This option is -detected before an attempt to open an option file. -Using this option will also prevent the creation of a -"~./gnupg" homedir. - -@item --load-extension @code{name} -Load an extension module. If @code{name} does not contain a slash it is -searched for in the directory configured when GnuPG was built -(generally "/usr/local/lib/gnupg"). Extensions are not generally -useful anymore, and the use of this option is deprecated. - -@item --debug @code{flags} -Set debugging flags. All flags are or-ed and @code{flags} may -be given in C syntax (e.g. 0x0042). - -@item --debug-all -Set all useful debugging flags. - -@item --debug-ccid-driver -Enable debug output from the included CCID driver for smartcards. -Note that this option is only available on some system. - -@item --enable-progress-filter -Enable certain PROGRESS status outputs. This option allows frontends -to display a progress indicator while gpg is processing larger files. -There is a slight performance overhead using it. - -@item --status-fd @code{n} -Write special status strings to the file descriptor @code{n}. -See the file DETAILS in the documentation for a listing of them. - -@item --status-file @code{file} -Same as --status-fd, except the status data is written to file -@code{file}. - -@item --logger-fd @code{n} -Write log output to file descriptor @code{n} and not to stderr. - -@item --logger-file @code{file} -Same as --logger-fd, except the logger data is written to file -@code{file}. - -@item --attribute-fd @code{n} -Write attribute subpackets to the file descriptor @code{n}. This is -most useful for use with --status-fd, since the status messages are -needed to separate out the various subpackets from the stream -delivered to the file descriptor. - -@item --attribute-file @code{file} -Same as --attribute-fd, except the attribute data is written to file -@code{file}. - -@item --comment @code{string} -@itemx --no-comments -Use @code{string} as a comment string in clear text signatures and -ASCII armored messages or keys (see --armor). The default behavior is -not to use a comment string. --comment may be repeated multiple times -to get multiple comment strings. --no-comments removes all comments. -It is a good idea to keep the length of a single comment below 60 -characters to avoid problems with mail programs wrapping such lines. -Note that comment lines, like all other header lines, are not -protected by the signature. - -@item --emit-version -@itemx --no-emit-version -Force inclusion of the version string in ASCII armored output. ---no-emit-version disables this option. - -@item --sig-notation @code{name=value} -@itemx --cert-notation @code{name=value} -@itemx -N, --set-notation @code{name=value} -Put the name value pair into the signature as notation data. -@code{name} must consist only of printable characters or spaces, and -must contain a '@@' character in the form keyname@@domain.example.com -(substituting the appropriate keyname and domain name, of course). -This is to help prevent pollution of the IETF reserved notation -namespace. The --expert flag overrides the '@@' check. @code{value} -may be any printable string; it will be encoded in UTF8, so you should -check that your --display-charset is set correctly. If you prefix -@code{name} with an exclamation mark (!), the notation data will be -flagged as critical (rfc2440:5.2.3.15). --sig-notation sets a -notation for data signatures. --cert-notation sets a notation for key -signatures (certifications). --set-notation sets both. - -There are special codes that may be used in notation names. "%k" will -be expanded into the key ID of the key being signed, "%K" into the -long key ID of the key being signed, "%f" into the fingerprint of the -key being signed, "%s" into the key ID of the key making the -signature, "%S" into the long key ID of the key making the signature, -"%g" into the fingerprint of the key making the signature (which might -be a subkey), "%p" into the fingerprint of the primary key of the key -making the signature, "%c" into the signature count from the OpenPGP -smartcard, and "%%" results in a single "%". %k, %K, and %f are only -meaningful when making a key signature (certification), and %c is only -meaningful when using the OpenPGP smartcard. - -@item --show-notation -@itemx --no-show-notation -Show signature notations in the --list-sigs or --check-sigs listings -as well as when verifying a signature with a notation in it. These -options are deprecated. Use `--list-options [no-]show-notation' -and/or `--verify-options [no-]show-notation' instead. - -@item --sig-policy-url @code{string} -@itemx --cert-policy-url @code{string} -@itemx --set-policy-url @code{string} -Use @code{string} as a Policy URL for signatures (rfc2440:5.2.3.19). -If you prefix it with an exclamation mark (!), the policy URL packet -will be flagged as critical. --sig-policy-url sets a policy url for -data signatures. --cert-policy-url sets a policy url for key -signatures (certifications). --set-policy-url sets both. - -The same %-expandos used for notation data are available here as well. - -@item --show-policy-url -@itemx --no-show-policy-url -Show policy URLs in the --list-sigs or --check-sigs listings as well -as when verifying a signature with a policy URL in it. These options -are deprecated. Use `--list-options [no-]show-policy-url' and/or -`--verify-options [no-]show-policy-url' instead. - -@item --sig-keyserver-url @code{string} -Use @code{string} as a preferred keyserver URL for data signatures. If -you prefix it with an exclamation mark, the keyserver URL packet will -be flagged as critical. - -The same %-expandos used for notation data are available here as well. - -@item --set-filename @code{string} -Use @code{string} as the filename which is stored inside messages. -This overrides the default, which is to use the actual filename of the -file being encrypted. - -@item --for-your-eyes-only -@itemx --no-for-your-eyes-only -Set the `for your eyes only' flag in the message. This causes GnuPG -to refuse to save the file unless the --output option is given, and -PGP to use the "secure viewer" with a Tempest-resistant font to -display the message. This option overrides --set-filename. ---no-for-your-eyes-only disables this option. - -@item --use-embedded-filename -@itemx --no-use-embedded-filename -Try to create a file with a name as embedded in the data. This can be -a dangerous option as it allows to overwrite files. Defaults to no. - -@item --completes-needed @code{n} -Number of completely trusted users to introduce a new -key signer (defaults to 1). - -@item --marginals-needed @code{n} -Number of marginally trusted users to introduce a new -key signer (defaults to 3) - -@item --max-cert-depth @code{n} -Maximum depth of a certification chain (default is 5). - -@item --cipher-algo @code{name} -Use @code{name} as cipher algorithm. Running the program with the -command --version yields a list of supported algorithms. If this is -not used the cipher algorithm is selected from the preferences stored -with the key. In general, you do not want to use this option as it -allows you to violate the OpenPGP standard. ---personal-cipher-preferences is the safe way to accomplish the same -thing. - -@item --digest-algo @code{name} -Use @code{name} as the message digest algorithm. Running the program -with the command --version yields a list of supported algorithms. In -general, you do not want to use this option as it allows you to -violate the OpenPGP standard. --personal-digest-preferences is the -safe way to accomplish the same thing. - -@item --compress-algo @code{name} -Use compression algorithm @code{name}. "zlib" is RFC-1950 ZLIB -compression. "zip" is RFC-1951 ZIP compression which is used by PGP. -"bzip2" is a more modern compression scheme that can compress some -things better than zip or zlib, but at the cost of more memory used -during compression and decompression. "uncompressed" or "none" -disables compression. If this option is not used, the default -behavior is to examine the recipient key preferences to see which -algorithms the recipient supports. If all else fails, ZIP is used for -maximum compatibility. - -ZLIB may give better compression results than ZIP, as the compression -window size is not limited to 8k. BZIP2 may give even better -compression results than that, but will use a significantly larger -amount of memory while compressing and decompressing. This may be -significant in low memory situations. Note, however, that PGP (all -versions) only supports ZIP compression. Using any algorithm other -than ZIP or "none" will make the message unreadable with PGP. In -general, you do not want to use this option as it allows you to -violate the OpenPGP standard. --personal-compress-preferences is the -safe way to accomplish the same thing. - -@item --cert-digest-algo @code{name} -Use @code{name} as the message digest algorithm used when signing a -key. Running the program with the command --version yields a list of -supported algorithms. Be aware that if you choose an algorithm that -GnuPG supports but other OpenPGP implementations do not, then some -users will not be able to use the key signatures you make, or quite -possibly your entire key. - -@item --s2k-cipher-algo @code{name} -Use @code{name} as the cipher algorithm used to protect secret keys. -The default cipher is CAST5. This cipher is also used for -conventional encryption if --personal-cipher-preferences and ---cipher-algo is not given. - -@item --s2k-digest-algo @code{name} -Use @code{name} as the digest algorithm used to mangle the passphrases. -The default algorithm is SHA-1. - -@item --s2k-mode @code{n} -Selects how passphrases are mangled. If @code{n} is 0 a plain -passphrase (which is not recommended) will be used, a 1 adds a salt to -the passphrase and a 3 (the default) iterates the whole process a -couple of times. Unless --rfc1991 is used, this mode is also used for -conventional encryption. - -@item --simple-sk-checksum -Secret keys are integrity protected by using a SHA-1 checksum. This -method is part of the upcoming enhanced OpenPGP specification but -GnuPG already uses it as a countermeasure against certain attacks. -Old applications don't understand this new format, so this option may -be used to switch back to the old behaviour. Using this option bears -a security risk. Note that using this option only takes effect when -the secret key is encrypted - the simplest way to make this happen is -to change the passphrase on the key (even changing it to the same -value is acceptable). - -@item --disable-cipher-algo @code{name} -Never allow the use of @code{name} as cipher algorithm. -The given name will not be checked so that a later loaded algorithm -will still get disabled. - -@item --disable-pubkey-algo @code{name} -Never allow the use of @code{name} as public key algorithm. -The given name will not be checked so that a later loaded algorithm -will still get disabled. - -@item --no-sig-cache -Do not cache the verification status of key signatures. -Caching gives a much better performance in key listings. However, if -you suspect that your public keyring is not save against write -modifications, you can use this option to disable the caching. It -probably does not make sense to disable it because all kind of damage -can be done if someone else has write access to your public keyring. - -@item --no-sig-create-check -GnuPG normally verifies each signature right after creation to protect -against bugs and hardware malfunctions which could leak out bits from -the secret key. This extra verification needs some time (about 115% -for DSA keys), and so this option can be used to disable it. -However, due to the fact that the signature creation needs manual -interaction, this performance penalty does not matter in most settings. - -@item --auto-check-trustdb -@itemx --no-auto-check-trustdb -If GnuPG feels that its information about the Web of Trust has to be -updated, it automatically runs the --check-trustdb command internally. -This may be a time consuming process. --no-auto-check-trustdb -disables this option. - -@item --throw-keyids -@itemx --no-throw-keyids -Do not put the recipient key IDs into encrypted messages. This helps -to hide the receivers of the message and is a limited countermeasure -against traffic analysis. On the receiving side, it may slow down the -decryption process because all available secret keys must be tried. ---no-throw-keyids disables this option. This option is essentially -the same as using --hidden-recipient for all recipients. - -@item --not-dash-escaped -This option changes the behavior of cleartext signatures -so that they can be used for patch files. You should not -send such an armored file via email because all spaces -and line endings are hashed too. You can not use this -option for data which has 5 dashes at the beginning of a -line, patch files don't have this. A special armor header -line tells GnuPG about this cleartext signature option. - -@item --escape-from-lines -@itemx --no-escape-from-lines -Because some mailers change lines starting with "From " to ">From -" it is good to handle such lines in a special way when creating -cleartext signatures to prevent the mail system from breaking the -signature. Note that all other PGP versions do it this way too. -Enabled by default. --no-escape-from-lines disables this option. - -@item --passphrase-fd @code{n} -Read the passphrase from file descriptor @code{n}. Only the first line -will be read from file descriptor @code{n}. If you use 0 for @code{n}, -the passphrase will be read from stdin. This can only be used if only -one passphrase is supplied. - -@item --passphrase-file @code{file} -Read the passphrase from file @code{file}. Only the first line will -be read from file @code{file}. This can only be used if only one -passphrase is supplied. Obviously, a passphrase stored in a file is -of questionable security if other users can read this file. Don't use -this option if you can avoid it. - -@item --passphrase @code{string} -Use @code{string} as the passphrase. This can only be used if only one -passphrase is supplied. Obviously, this is of very questionable -security on a multi-user system. Don't use this option if you can -avoid it. - -@item --command-fd @code{n} -This is a replacement for the deprecated shared-memory IPC mode. -If this option is enabled, user input on questions is not expected -from the TTY but from the given file descriptor. It should be used -together with --status-fd. See the file doc/DETAILS in the source -distribution for details on how to use it. - -@item --command-file @code{file} -Same as --command-fd, except the commands are read out of file -@code{file} - -@item --use-agent -@itemx --no-use-agent -Try to use the GnuPG-Agent. Please note that this agent is still under -development. With this option, GnuPG first tries to connect to the -agent before it asks for a passphrase. --no-use-agent disables this -option. - -@item --gpg-agent-info -Override the value of the environment variable -@samp{GPG_AGENT_INFO}. This is only used when --use-agent has been given - -@item Compliance options -These options control what GnuPG is compliant to. Only one of these -options may be active at a time. Note that the default setting of -this is nearly always the correct one. See the INTEROPERABILITY WITH -OTHER OPENPGP PROGRAMS section below before using one of these -options. - -@table @asis - -@item --gnupg -Use standard GnuPG behavior. This is essentially OpenPGP behavior -(see --openpgp), but with some additional workarounds for common -compatibility problems in different versions of PGP. This is the -default option, so it is not generally needed, but it may be useful to -override a different compliance option in the gpg.conf file. - -@item --openpgp -Reset all packet, cipher and digest options to strict OpenPGP -behavior. Use this option to reset all previous options like ---rfc1991, --force-v3-sigs, --s2k-*, --cipher-algo, --digest-algo and ---compress-algo to OpenPGP compliant values. All PGP workarounds are -disabled. - -@item --rfc2440 -Reset all packet, cipher and digest options to strict RFC-2440 -behavior. Note that this is currently the same thing as --openpgp. - -@item --rfc1991 -Try to be more RFC-1991 (PGP 2.x) compliant. - -@item --pgp2 -Set up all options to be as PGP 2.x compliant as possible, and warn if -an action is taken (e.g. encrypting to a non-RSA key) that will create -a message that PGP 2.x will not be able to handle. Note that `PGP -2.x' here means `MIT PGP 2.6.2'. There are other versions of PGP 2.x -available, but the MIT release is a good common baseline. - -This option implies `--rfc1991 --disable-mdc --no-force-v4-certs ---no-sk-comment --escape-from-lines --force-v3-sigs ---no-ask-sig-expire --no-ask-cert-expire --cipher-algo IDEA ---digest-algo MD5 --compress-algo 1'. It also disables --textmode -when encrypting. - -@item --pgp6 -Set up all options to be as PGP 6 compliant as possible. This -restricts you to the ciphers IDEA (if the IDEA plugin is installed), -3DES, and CAST5, the hashes MD5, SHA1 and RIPEMD160, and the -compression algorithms none and ZIP. This also disables ---throw-keyids, and making signatures with signing subkeys as PGP 6 -does not understand signatures made by signing subkeys. - -This option implies `--disable-mdc --no-sk-comment --escape-from-lines ---force-v3-sigs --no-ask-sig-expire' - -@item --pgp7 -Set up all options to be as PGP 7 compliant as possible. This is -identical to --pgp6 except that MDCs are not disabled, and the list of -allowable ciphers is expanded to add AES128, AES192, AES256, and -TWOFISH. - -@item --pgp8 -Set up all options to be as PGP 8 compliant as possible. PGP 8 is a -lot closer to the OpenPGP standard than previous versions of PGP, so -all this does is disable --throw-keyids and set --escape-from-lines. -All algorithms are allowed except for the SHA224, SHA384, and SHA512 -digests. -@end table - -@item --force-v3-sigs -@itemx --no-force-v3-sigs -OpenPGP states that an implementation should generate v4 signatures -but PGP versions 5 through 7 only recognize v4 signatures on key -material. This option forces v3 signatures for signatures on data. -Note that this option overrides --ask-sig-expire, as v3 signatures -cannot have expiration dates. --no-force-v3-sigs disables this -option. - -@item --force-v4-certs -@itemx --no-force-v4-certs -Always use v4 key signatures even on v3 keys. This option also -changes the default hash algorithm for v3 RSA keys from MD5 to SHA-1. ---no-force-v4-certs disables this option. - -@item --force-mdc -Force the use of encryption with a modification detection code. This -is always used with the newer ciphers (those with a blocksize greater -than 64 bits), or if all of the recipient keys indicate MDC support in -their feature flags. - -@item --disable-mdc -Disable the use of the modification detection code. Note that by -using this option, the encrypted message becomes vulnerable to a -message modification attack. - -@item --allow-non-selfsigned-uid -@itemx --no-allow-non-selfsigned-uid -Allow the import and use of keys with user IDs which are not -self-signed. This is not recommended, as a non self-signed user ID is -trivial to forge. --no-allow-non-selfsigned-uid disables. - -@item --allow-freeform-uid -Disable all checks on the form of the user ID while generating a new -one. This option should only be used in very special environments as -it does not ensure the de-facto standard format of user IDs. - -@item --ignore-time-conflict -GnuPG normally checks that the timestamps associated with keys and -signatures have plausible values. However, sometimes a signature -seems to be older than the key due to clock problems. This option -makes these checks just a warning. See also --ignore-valid-from for -timestamp issues on subkeys. - -@item --ignore-valid-from -GnuPG normally does not select and use subkeys created in the future. -This option allows the use of such keys and thus exhibits the -pre-1.0.7 behaviour. You should not use this option unless you there -is some clock problem. See also --ignore-time-conflict for timestamp -issues with signatures. - -@item --ignore-crc-error -The ASCII armor used by OpenPGP is protected by a CRC checksum against -transmission errors. Occasionally the CRC gets mangled somewhere on -the transmission channel but the actual content (which is protected by -the OpenPGP protocol anyway) is still okay. This option allows GnuPG -to ignore CRC errors. - -@item --ignore-mdc-error -This option changes a MDC integrity protection failure into a warning. -This can be useful if a message is partially corrupt, but it is -necessary to get as much data as possible out of the corrupt message. -However, be aware that a MDC protection failure may also mean that the -message was tampered with intentionally by an attacker. - -@item --lock-once -Lock the databases the first time a lock is requested -and do not release the lock until the process -terminates. - -@item --lock-multiple -Release the locks every time a lock is no longer -needed. Use this to override a previous --lock-once -from a config file. - -@item --lock-never -Disable locking entirely. This option should be used only in very -special environments, where it can be assured that only one process -is accessing those files. A bootable floppy with a stand-alone -encryption system will probably use this. Improper usage of this -option may lead to data and key corruption. - -@item --exit-on-status-write-error -This option will cause write errors on the status FD to immediately -terminate the process. That should in fact be the default but it -never worked this way and thus we need an option to enable this, so -that the change won't break applications which close their end of a -status fd connected pipe too early. Using this option along with ---enable-progress-filter may be used to cleanly cancel long running -gpg operations. - -@item --limit-card-insert-tries @code{n} -With @code{n} greater than 0 the number of prompts asking to insert a -smartcard gets limited to N-1. Thus with a value of 1 gpg won't at -all ask to insert a card if none has been inserted at startup. This -option is useful in the configuration file in case an application does -not know about the smartcard support and waits ad infinitum for an -inserted card. - -@item --no-random-seed-file -GnuPG uses a file to store its internal random pool over invocations. -This makes random generation faster; however sometimes write operations -are not desired. This option can be used to achieve that with the cost of -slower random generation. - -@item --no-verbose -Reset verbose level to 0. - -@item --no-greeting -Suppress the initial copyright message. - -@item --no-secmem-warning -Suppress the warning about "using insecure memory". - -@item --no-permission-warning -Suppress the warning about unsafe file and home directory (--homedir) -permissions. Note that the permission checks that GnuPG performs are -not intended to be authoritative, but rather they simply warn about -certain common permission problems. Do not assume that the lack of a -warning means that your system is secure. - -Note that the warning for unsafe --homedir permissions cannot be -suppressed in the gpg.conf file, as this would allow an attacker to -place an unsafe gpg.conf file in place, and use this file to suppress -warnings about itself. The --homedir permissions warning may only be -suppressed on the command line. - -@item --no-mdc-warning -Suppress the warning about missing MDC integrity protection. - -@item --require-secmem -@itemx --no-require-secmem -Refuse to run if GnuPG cannot get secure memory. Defaults to no -(i.e. run, but give a warning). - -@item --no-armor -Assume the input data is not in ASCII armored format. - -@item --no-default-keyring -Do not add the default keyrings to the list of keyrings. Note that -GnuPG will not operate without any keyrings, so if you use this option -and do not provide alternate keyrings via --keyring or ---secret-keyring, then GnuPG will still use the default public or -secret keyrings. - -@item --skip-verify -Skip the signature verification step. This may be -used to make the decryption faster if the signature -verification is not needed. - -@item --with-colons -Print key listings delimited by colons. Note that the output will be -encoded in UTF-8 regardless of any --display-charset setting. This -format is useful when GnuPG is called from scripts and other programs -as it is easily machine parsed. The details of this format are -documented in the file doc/DETAILS, which is included in the GnuPG -source distribution. - -@item --with-key-data -Print key listings delimited by colons (like --with-colons) and print the public key data. - -@item --with-fingerprint -Same as the command --fingerprint but changes only the format of the output -and may be used together with another command. - -@item --fast-list-mode -Changes the output of the list commands to work faster; this is achieved -by leaving some parts empty. Some applications don't need the user ID and -the trust information given in the listings. By using this options they -can get a faster listing. The exact behaviour of this option may change -in future versions. - -@item --fixed-list-mode -Do not merge primary user ID and primary key in --with-colon listing -mode and print all timestamps as seconds since 1970-01-01. - -@item --list-only -Changes the behaviour of some commands. This is like --dry-run but -different in some cases. The semantic of this command may be extended in -the future. Currently it only skips the actual decryption pass and -therefore enables a fast listing of the encryption keys. - -@item --no-literal -This is not for normal use. Use the source to see for what it might be useful. - -@item --set-filesize -This is not for normal use. Use the source to see for what it might be useful. - -@item --show-session-key -Display the session key used for one message. See --override-session-key -for the counterpart of this option. - -We think that Key Escrow is a Bad Thing; however the user should have -the freedom to decide whether to go to prison or to reveal the content -of one specific message without compromising all messages ever -encrypted for one secret key. DON'T USE IT UNLESS YOU ARE REALLY -FORCED TO DO SO. - -@item --override-session-key @code{string} -Don't use the public key but the session key @code{string}. The format of this -string is the same as the one printed by --show-session-key. This option -is normally not used but comes handy in case someone forces you to reveal the -content of an encrypted message; using this option you can do this without -handing out the secret key. - -@item --require-cross-certification -@itemx --no-require-certification -When verifying a signature made from a subkey, ensure that the cross -certification "back signature" on the subkey is present and valid. -This protects against a subtle attack against subkeys that can sign. -Currently defaults to --no-require-cross-certification, but will be -changed to --require-cross-certification in the future. - -@item --ask-sig-expire -@itemx --no-ask-sig-expire -When making a data signature, prompt for an expiration time. If this -option is not specified, the expiration time set via ---default-sig-expire is used. --no-ask-sig-expire disables this -option. Note that by default, --force-v3-sigs is set which also -disables this option. If you want signature expiration, you must set ---no-force-v3-sigs as well as turning --ask-sig-expire on. - -@item --default-sig-expire -The default expiration time to use for signature expiration. Valid -values are "0" for no expiration, a number followed by the letter d -(for days), w (for weeks), m (for months), or y (for years) (for -example "2m" for two months, or "5y" for five years), or an absolute -date in the form YYYY-MM-DD. Defaults to "0". - -@item --ask-cert-expire -@itemx --no-ask-cert-expire -When making a key signature, prompt for an expiration time. If this -option is not specified, the expiration time set via ---default-cert-expire is used. --no-ask-cert-expire disables this -option. - -@item --default-cert-expire -The default expiration time to use for key signature expiration. -Valid values are "0" for no expiration, a number followed by the -letter d (for days), w (for weeks), m (for months), or y (for years) -(for example "2m" for two months, or "5y" for five years), or an -absolute date in the form YYYY-MM-DD. Defaults to "0". - -@item --expert -@itemx --no-expert -Allow the user to do certain nonsensical or "silly" things like -signing an expired or revoked key, or certain potentially incompatible -things like generating unusual key types. This also disables certain -warning messages about potentially incompatible actions. As the name -implies, this option is for experts only. If you don't fully -understand the implications of what it allows you to do, leave this -off. --no-expert disables this option. - -@item --allow-secret-key-import -This is an obsolete option and is not used anywhere. - -@item --try-all-secrets -Don't look at the key ID as stored in the message but try all secret -keys in turn to find the right decryption key. This option forces the -behaviour as used by anonymous recipients (created by using ---throw-keyids) and might come handy in case where an encrypted -message contains a bogus key ID. - -@item --allow-multisig-verification -Allow verification of concatenated signed messages. This will run a -signature verification for each data+signature block. There are some -security issues with this option and thus it is off by default. Note -that versions of GPG prior to version 1.4.3 implicitly allowed this. - -@item --enable-special-filenames -This options enables a mode in which filenames of the form -@file{-&n}, where n is a non-negative decimal number, -refer to the file descriptor n and not to a file with that name. - -@item --no-expensive-trust-checks -Experimental use only. - -@item --group @code{name=value1 } -Sets up a named group, which is similar to aliases in email programs. -Any time the group name is a recipient (-r or --recipient), it will be -expanded to the values specified. Multiple groups with the same name -are automatically merged into a single group. - -The values are @code{key IDs} or fingerprints, but any key description -is accepted. Note that a value with spaces in it will be treated as -two different values. Note also there is only one level of expansion -- you cannot make an group that points to another group. When used -from the command line, it may be necessary to quote the argument to -this option to prevent the shell from treating it as multiple -arguments. - -@item --ungroup @code{name} -Remove a given entry from the --group list. - -@item --no-groups -Remove all entries from the --group list. - -@item --preserve-permissions -Don't change the permissions of a secret keyring back to user -read/write only. Use this option only if you really know what you are doing. - -@item --personal-cipher-preferences @code{string} -Set the list of personal cipher preferences to @code{string}, this list -should be a string similar to the one printed by the command "pref" in -the edit menu. This allows the user to factor in their own preferred -algorithms when algorithms are chosen via recipient key preferences. -The most highly ranked cipher in this list is also used for the ---symmetric encryption command. - -@item --personal-digest-preferences @code{string} -Set the list of personal digest preferences to @code{string}, this list -should be a string similar to the one printed by the command "pref" in -the edit menu. This allows the user to factor in their own preferred -algorithms when algorithms are chosen via recipient key preferences. -The most highly ranked digest algorithm in this list is algo used when -signing without encryption (e.g. --clearsign or --sign). The default -value is SHA-1. - -@item --personal-compress-preferences @code{string} -Set the list of personal compression preferences to @code{string}, this -list should be a string similar to the one printed by the command -"pref" in the edit menu. This allows the user to factor in their own -preferred algorithms when algorithms are chosen via recipient key -preferences. The most highly ranked algorithm in this list is also -used when there are no recipient keys to consider (e.g. --symmetric). - -@item --default-preference-list @code{string} -Set the list of default preferences to @code{string}. This preference -list is used for new keys and becomes the default for "setpref" in the -edit menu. - -@item --default-keyserver-url @code{name} -Set the default keyserver URL to @code{name}. This keyserver will be -used as the keyserver URL when writing a new self-signature on a key, -which includes key generation and changing preferences. - -@item --list-config -Display various internal configuration parameters of GnuPG. This -option is intended for external programs that call GnuPG to perform -tasks, and is thus not generally useful. See the file -@file{doc/DETAILS} in the source distribution for the -details of which configuration items may be listed. --list-config is -only usable with --with-colons set. -@end table -@chapheading How to specify a user ID - -There are different ways to specify a user ID to GnuPG; here are some -examples: - -@table @asis - -@item - -@item 234567C4 -@itemx 0F34E556E -@itemx 01347A56A -@itemx 0xAB123456 -Here the key ID is given in the usual short form. - -@item 234AABBCC34567C4 -@itemx 0F323456784E56EAB -@itemx 01AB3FED1347A5612 -@itemx 0x234AABBCC34567C4 -Here the key ID is given in the long form as used by OpenPGP -(you can get the long key ID using the option --with-colons). - -@item 1234343434343434C434343434343434 -@itemx 123434343434343C3434343434343734349A3434 -@itemx 0E12343434343434343434EAB3484343434343434 -@itemx 0xE12343434343434343434EAB3484343434343434 -The best way to specify a key ID is by using the fingerprint of -the key. This avoids any ambiguities in case that there are duplicated -key IDs (which are really rare for the long key IDs). - -@item =Heinrich Heine <heinrichh@@uni-duesseldorf.de> -Using an exact to match string. The equal sign indicates this. - -@item <heinrichh@@uni-duesseldorf.de> -Using the email address part which must match exactly. The left angle bracket -indicates this email address mode. - -@item @@heinrichh -Match within the <email.address> part of a user ID. The at sign -indicates this email address mode. - -@item Heine -@itemx *Heine -By case insensitive substring matching. This is the default mode but -applications may want to explicitly indicate this by putting the asterisk -in front. -@end table - -Note that you can append an exclamation mark (!) to key IDs or -fingerprints. This flag tells GnuPG to use the specified primary or -secondary key and not to try and calculate which primary or secondary -key to use. -@chapheading RETURN VALUE - -The program returns 0 if everything was fine, 1 if at least -a signature was bad, and other error codes for fatal errors. -@chapheading EXAMPLES - -@table @asis - -@item gpg -se -r @code{Bob} @code{file} -sign and encrypt for user Bob - -@item gpg --clearsign @code{file} -make a clear text signature - -@item gpg -sb @code{file} -make a detached signature - -@item gpg --list-keys @code{user_ID} -show keys - -@item gpg --fingerprint @code{user_ID} -show fingerprint - -@item gpg --verify @code{pgpfile} -@itemx gpg --verify @code{sigfile} -Verify the signature of the file but do not output the data. The -second form is used for detached signatures, where @code{sigfile} -is the detached signature (either ASCII armored or binary) and -are the signed data; if this is not given, the name of -the file holding the signed data is constructed by cutting off the -extension (".asc" or ".sig") of @code{sigfile} or by asking the -user for the filename. -@end table -@chapheading ENVIRONMENT - -@table @asis - -@item HOME -Used to locate the default home directory. - -@item GNUPGHOME -If set directory used instead of "~/.gnupg". - -@item GPG_AGENT_INFO -Used to locate the gpg-agent; only honored when ---use-agent is set. The value consists of 3 colon delimited fields: -The first is the path to the Unix Domain Socket, the second the PID of -the gpg-agent and the protocol version which should be set to 1. When -starting the gpg-agent as described in its documentation, this -variable is set to the correct value. The option --gpg-agent-info can -be used to override it. - -@item COLUMNS -@itemx LINES -Used to size some displays to the full size of the screen. -@end table -@chapheading FILES - -@table @asis - -@item ~/.gnupg/secring.gpg -The secret keyring - -@item ~/.gnupg/secring.gpg.lock -and the lock file - -@item ~/.gnupg/pubring.gpg -The public keyring - -@item ~/.gnupg/pubring.gpg.lock -and the lock file - -@item ~/.gnupg/trustdb.gpg -The trust database - -@item ~/.gnupg/trustdb.gpg.lock -and the lock file - -@item ~/.gnupg/random_seed -used to preserve the internal random pool - -@item ~/.gnupg/gpg.conf -Default configuration file - -@item ~/.gnupg/options -Old style configuration file; only used when gpg.conf -is not found - -@item /usr[/local]/share/gnupg/options.skel -Skeleton options file - -@item /usr[/local]/lib/gnupg/ -Default location for extensions -@end table -@chapheading WARNINGS - -Use a *good* password for your user account and a *good* passphrase -to protect your secret key. This passphrase is the weakest part of the -whole system. Programs to do dictionary attacks on your secret keyring -are very easy to write and so you should protect your "~/.gnupg/" -directory very well. - -Keep in mind that, if this program is used over a network (telnet), it -is *very* easy to spy out your passphrase! - -If you are going to verify detached signatures, make sure that the -program knows about it; either give both filenames on the command line -or use @samp{-} to specify stdin. -@chapheading INTEROPERABILITY WITH OTHER OPENPGP PROGRAMS - -GnuPG tries to be a very flexible implementation of the OpenPGP -standard. In particular, GnuPG implements many of the optional parts -of the standard, such as the SHA-512 hash, and the ZLIB and BZIP2 -compression algorithms. It is important to be aware that not all -OpenPGP programs implement these optional algorithms and that by -forcing their use via the --cipher-algo, --digest-algo, ---cert-digest-algo, or --compress-algo options in GnuPG, it is -possible to create a perfectly valid OpenPGP message, but one that -cannot be read by the intended recipient. - -There are dozens of variations of OpenPGP programs available, and each -supports a slightly different subset of these optional algorithms. -For example, until recently, no (unhacked) version of PGP supported -the BLOWFISH cipher algorithm. A message using BLOWFISH simply could -not be read by a PGP user. By default, GnuPG uses the standard -OpenPGP preferences system that will always do the right thing and -create messages that are usable by all recipients, regardless of which -OpenPGP program they use. Only override this safe default if you -really know what you are doing. - -If you absolutely must override the safe default, or if the -preferences on a given key are invalid for some reason, you are far -better off using the --pgp6, --pgp7, or --pgp8 options. These options -are safe as they do not force any particular algorithms in violation -of OpenPGP, but rather reduce the available algorithms to a "PGP-safe" -list. -@chapheading BUGS - -On many systems this program should be installed as setuid(root). This -is necessary to lock memory pages. Locking memory pages prevents the -operating system from writing memory pages (which may contain -passphrases or other sensitive material) to disk. If you get no -warning message about insecure memory your operating system supports -locking without being root. The program drops root privileges as soon -as locked memory is allocated. - -@bye |