GPGV(1) GNU Privacy Guard 2.2 GPGV(1)
NAME
gpgv - Verify OpenPGP signatures
SYNOPSIS
gpgv [options] signed_files
DESCRIPTION
gpgv is an OpenPGP signature verification tool.
This program is actually a stripped-down version of gpg which is only
able to check signatures. It is somewhat smaller than the fully-blown
gpg and uses a different (and simpler) way to check that the public
keys used to make the signature are valid. There are no configuration
files and only a few options are implemented.
gpgv assumes that all keys in the keyring are trustworthy. That does
also mean that it does not check for expired or revoked keys.
If no --keyring option is given, gpgv looks for a ``default'' keyring
named 'trustedkeys.kbx' (preferred) or 'trustedkeys.gpg' in the home
directory of GnuPG, either the default home directory or the one set by
the --homedir option or the GNUPGHOME environment variable. If any
--keyring option is used, gpgv will not look for the default keyring.
The --keyring option may be used multiple times and all specified
keyrings will be used together.
RETURN VALUE
The program returns 0 if everything is fine, 1 if at least one signa-
ture was bad, and other error codes for fatal errors.
OPTIONS
gpgv recognizes these options:
--verbose
-v Gives more information during processing. If used twice, the in-
put data is listed in detail.
--quiet
-q Try to be as quiet as possible.
--keyring file
Add file to the list of keyrings. If 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
home-directory ("~/.gnupg" if --homedir is not used).
--output file
-o file
Write output to file; to write to stdout use -. This option can
be used to get the signed text from a cleartext or binary signa-
ture; it also works for detached signatures, but in that case
this option is in general not useful. Note that an existing
file will be overwritten.
--status-fd n
Write special status strings to the file descriptor n. See the
file DETAILS in the documentation for a listing of them.
--logger-fd n
Write log output to file descriptor n and not to stderr.
--log-file file
Same as --logger-fd, except the logger data is written to file
file. Use 'socket://' to log to socket.
--ignore-time-conflict
GnuPG normally checks that the timestamps associated with keys
and signatures have plausible values. However, sometimes a sig-
nature seems to be older than the key due to clock problems.
This option turns these checks into warnings.
--homedir dir
Set the name of the home directory to dir. If this option is not
used, the home directory defaults to '~/.gnupg'. It is only
recognized when given on the command line. It also overrides
any home directory stated through the environment variable
'GNUPGHOME' or (on Windows systems) by means of the Registry en-
try HKCU\Software\GNU\GnuPG:HomeDir.
On Windows systems it is possible to install GnuPG as a portable
application. In this case only this command line option is con-
sidered, all other ways to set a home directory are ignored.
To install GnuPG as a portable application under Windows, create
an empty file named 'gpgconf.ctl' in the same directory as the
tool 'gpgconf.exe'. The root of the installation is then that
directory; or, if 'gpgconf.exe' has been installed directly be-
low a directory named 'bin', its parent directory. You also
need to make sure that the following directories exist and are
writable: 'ROOT/home' for the GnuPG home and
'ROOT/var/cache/gnupg' for internal cache files.
--weak-digest name
Treat the specified digest algorithm as weak. Signatures made
over weak digests algorithms are normally rejected. This option
can be supplied multiple times if multiple algorithms should be
considered weak. MD5 is always considered weak, and does not
need to be listed explicitly.
--enable-special-filenames
This option enables a mode in which filenames of the form '-&n',
where n is a non-negative decimal number, refer to the file de-
scriptor n and not to a file with that name.
EXAMPLES
gpgv pgpfile
gpgv sigfile [datafile]
Verify the signature of the file. The second form is used for
detached signatures, where sigfile is the detached signature
(either ASCII-armored or binary) and datafile contains the
signed data; if datafile is "-" the signed data is expected on
stdin; if datafile is not given the name of the file holding the
signed data is constructed by cutting off the extension (".asc",
".sig" or ".sign") from sigfile.
FILES
~/.gnupg/trustedkeys.gpg
The default keyring with the allowed keys.
ENVIRONMENT
HOME Used to locate the default home directory.
GNUPGHOME
If set directory used instead of "~/.gnupg".
SEE ALSO
gpg(1)
The full documentation for this tool is maintained as a Texinfo manual.
If GnuPG and the info program are properly installed at your site, the
command
info gnupg
should give you access to the complete manual including a menu struc-
ture and an index.
GnuPG 2.2.20 2020-03-18 GPGV(1)