Ubuntu Manpage: Crack, Reporter - programs to break password files

NAME

       Crack, Reporter - programs to break password files

SYNOPSIS

       Crack [options] [-fmt format] [file ...]
       Crack-Reporter [-quiet] [-html]

DESCRIPTION

       This  manual  page  documents briefly the Crack, and Crack-Reporter commands.  This manual
       page was written for the Debian GNU/Linux distribution because the original  program  does
       not   have   a   manual   page.    Instead,  there  is  some  documentation  available  at
       /usr/share/doc/crack which you are encouraged to read

       Crack is not a program designed to break the password of every user in the file.   Rather,
       it  is  designed  to  find  weak  passwords  in  the file, by attacking those sorts of bad
       passwords which are most likely to be used, in the order in which they would  most  easily
       be found (ie: are most likely to be used by a moronic user).

       Crack  is  not  designed  to break user passwords; it is designed to break password files.
       This is a subtle but important distinction.

       Crack-Reporter will show what passwords have been cracked, as well  as  view  errors  that
       have been detected in the source password files, etc.  Guesses are listed chronologically,
       so users who wish to see incremental changes in the output as Crack continues to run  over
       a  course  of  days  or  weeks,  are encouraged to wrap invocations of Crack-Reporter in a
       script with diff.

OPTIONS

A summary of options are included below. For Crack:

-makedict
Creates and compresses the dictionaries Crack will use

-makeonly
Compiles the binaries for Crack (not necessary for Debian GNU/Linux since they are
already provided)

-debug Lets you see what the Crack script is doing.

-recover
Used when restarting an abnormally-terminated run; suppresses rebuild of the gecos-
derived dictionaries.

-fgnd Runs the password cracker in the foreground, with stdin, stdout and stderr attached
to the usual places.

-fmt format
Specifies the input file format.

-from N
Starts password cracking from rule number "N".

-keep Prevents deletion of the temporary file used to store the password cracker's input.

-mail E-Mail a warning message to anyone whose password is cracked. See the script
nastygram.

-network
Runs the password cracker in network mode.

-nice N
Runs the password cracker at a reduced priority, so that other jobs can take
priority over the CPU.

-kill filename

-remote
Internal options used to support networking.

For Crack-Reporter -html Produces output in a fairly basic HTML-readable format.
-quiet Suppresses the reporting of errors in the password file (corrupt entries,
etc)

EXAMPLES

       To run Crack

          # Crack -nice 10 /etc/passwd

       If a Crack session is killed accidentally, it can be restarted with moderate efficiency by
       doing:

           mv run/Dhostname.N run/tempfilename
           Crack -recover -fmt spf run/tempfilename

       However if all you wish to do is start cracking passwords from some specific rule  number,
       or to restart a run whilst skipping over a few rulesets, try:

           Crack [-recover] -from N filename ...

       ...where N is the number of the rule to start working from.

FILES

       /usr/share/Crack  Location of the Crack program and scripts.  /var/lib/Crack/ Location for
       the temporary files used by Crack.

AUTHOR

       This  manual  page was written by Javier Fernández-Sanguino Peña <jfs@debian.org>, for the
       Debian GNU/Linux system (but may be used by others).

       Crack and Crack-Reporter  (originally  called  Reporter)  were  written  by  Alec  Muffett
       <Alec.Muffett@UK.Sun.COM>

                                                                                         CRACK(8)