NAME

       canlock - CLI frontend for libcanlock library

SYNOPSIS

       canlock -h | -v

       canlock [-q] -o

       canlock [-a scheme] -l [uid]mid

       canlock [-a scheme] -k [uid]mid

       canlock [-q] -c key,lock

DESCRIPTION

       Command line utility for Netnews Cancel-Lock authentication scheme.

       canlock  can  be  used  to create <c-lock> and <c-key> elements according to RFC8315.  The
       secret data is read from standard input (using EOF for termination).

       canlock also provides a verify interface with the -c option.  An external header parser is
       required to extract the <c-key> and <c-lock> elements from the article headers.
       The command line utilities canlock-mhp(1) and canlock-hfp(1) can be used for this purpose.

OPTIONS

       The following options are supported:

       -a scheme                Use the hash algorithm specified by <scheme>.
                                Supported values for <scheme> (by version 3.0.0 of canlock):
                                sha1, sha224, sha256, sha384, sha512

                                If  this  option  is not present, sha256 is used as default value
                                (because this is the mandatory algorithm defined by RFC8315).

       -l [uid]mid              Generate Cancel-Lock for Message-ID <mid>.
                                The Message-ID can be prepended with an optional User-ID <uid>.

                                The result is a <c-lock> element.

       -k [uid]mid              Generate Cancel-Key for Message-ID <mid>.
                                The Message-ID can be prepended with an optional User-ID <uid>.

                                The result is a <c-key> element.

       -c c-key,c-lock          Verify whether <c-key> element of a cancel or  supersede  matches
                                the <c-lock> element of a target article.

       -q                       Write no result to standard output.

                                Only valid if specified before -c and -o options.

       -h                       Print help message, then exit.

       -o                       Print  whether  libcanlock reports support for overwriting secret
                                data in memory.

                                The exit status is zero if cl_clear_secret(3) returned zero.

       -v                       Print version and compile time options, then exit.

EXIT STATUS

       Zero on success or regular exit respectively.
       All other values indicate an error.

AUTHORS

       Michael Baeuerle

REPORTING BUGS

       Report bugs to <mailto:michael.baeuerle@gmx.net>.

STANDARDS

       canlock tries to comply with the following standards:

       RFC5537, RFC6234, RFC8315

SEE ALSO

       canlock-hfp(1),   canlock-mhp(1),   cl_clear_secret(3),   cl_get_lock(3),   cl_get_key(3),
       cl_split(3), cl_verify(3)
       http://en.wikipedia.org/wiki/Usenet