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.

   By default a keyring named 'trustedkeys.kbx' is used; if that does  not
   exist  a  keyring named 'trustedkeys.gpg' is used.  The default keyring
   is assumed to be in the home directory of  GnuPG,  either  the  default
   home  directory or the one set by an option or an environment variable.
   The option --keyring may be used to specify a different keyring or even
   multiple keyrings.

RETURN VALUE

   The  program  returns  0  if  everything  is  fine,  1  if at least one
   signature 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
          input 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).

   --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.

   --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 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
          entry 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
          considered, all other ways to set a home directory are ignored.

          To install GnuPG as a portable application under Windows, create
          an empty file name 'gpgconf.ctl' in the same  directory  as  the
          tool  'gpgconf.exe'.   The root of the installation is than that
          directory; or, if  'gpgconf.exe'  has  been  installed  directly
          below  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.

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

   gpg2(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
   structure and an index.

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