man 8 cryptsetup-bitlkDump

CRYPTSETUP-BITLKDUMP(8)      Maintenance Commands      CRYPTSETUP-BITLKDUMP(8)

NAME
       cryptsetup-bitlkDump - dump the header information of a BITLK
       (BitLocker compatible) device

SYNOPSIS
       cryptsetup bitlkDump [<options>] <device> 

DESCRIPTION
       Dump the header information of a BITLK (BitLocker compatible) device.

       If the --dump-volume-key option is used, the BITLK device volume key is
       dumped instead of header information. You have to provide password or
       keyfile to dump volume key.

       Beware that the volume key can be used to decrypt the data stored in
       the container without a passphrase. This means that if the volume key
       is compromised, the whole device has to be erased to prevent further
       access. Use this option carefully.

       <options> can be [--dump-volume-key, --volume-key-file, --key-file,
       --keyfile-offset, --keyfile-size, --timeout].

OPTIONS
       --batch-mode, -q
           Suppresses all confirmation questions. Use with care!

           If the --verify-passphrase option is not specified, this option
           also switches off the passphrase verification.

       --debug or --debug-json
           Run in debug mode with full diagnostic logs. Debug output lines are
           always prefixed by #.

           If --debug-json is used, additional LUKS2 JSON data structures are
           printed.

       --dump-volume-key, --dump-master-key (OBSOLETE alias)
           Print the volume key in the displayed information. Use with care,
           as the volume key can be used to bypass the passphrases, see also
           option --volume-key-file.

       --help, -?
           Show help text and default parameters.

       --key-file, -d name
           Read the passphrase from file.

           If the name given is "-", then the passphrase will be read from
           stdin. In this case, reading will not stop at newline characters.

           See section NOTES ON PASSPHRASE PROCESSING in cryptsetup(8) for
           more information.

       --keyfile-offset value
           Skip value bytes at the beginning of the key file.

       --keyfile-size, -l value
           Read a maximum of value bytes from the key file. The default is to
           read the whole file up to the compiled-in maximum that can be
           queried with --help. Supplying more data than the compiled-in
           maximum aborts the operation.

           This option is useful to cut trailing newlines, for example. If
           --keyfile-offset is also given, the size count starts after the
           offset.

       --timeout, -t <number of seconds> 
           The number of seconds to wait before timeout on passphrase input
           via terminal. It is relevant every time a passphrase is asked. It
           has no effect if used in conjunction with --key-file.

           This option is useful when the system should not stall if the user
           does not input a passphrase, e.g. during boot. The default is a
           value of 0 seconds, which means to wait forever.

       --usage
           Show short option help.

       --version, -V
           Show the program version.

       --volume-key-file, --master-key-file (OBSOLETE alias)
           Use a volume key stored in a file. The volume key is stored in a
           file instead of being printed out to standard output.

REPORTING BUGS
       Report bugs at cryptsetup mailing list <cryptsetup@lists.linux.dev> or
       in Issues project section
       <https://gitlab.com/cryptsetup/cryptsetup/-/issues/new>.

       Please attach output of the failed command with --debug option added.

SEE ALSO
       Cryptsetup FAQ
       <https://gitlab.com/cryptsetup/cryptsetup/wikis/FrequentlyAskedQuestions> 

       cryptsetup(8), integritysetup(8) and veritysetup(8)

CRYPTSETUP
       Part of cryptsetup project <https://gitlab.com/cryptsetup/cryptsetup/>.

cryptsetup 2.7.2                  2025-06-13           CRYPTSETUP-BITLKDUMP(8)