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       Crack, Reporter - programs to break password files


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


       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.


       A summary of options are included below.  For Crack:

              Creates and compresses the dictionaries Crack will use

              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.

              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.

              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

              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)


       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.


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


       You  will  find  more  documentation  about  Crack  in  the  text files
       available in  /usr/share/doc/crack-common  Documentation  includes  the
       program’s  Manual (in HTML and Text files), the User’s Frequently Asked
       Questions (FAQ), examples, articles and even some humour.


       This   manual   page   was   written   by   Javier   Fernandez-Sanguino
       <>,  for  the Debian GNU/Linux system (but may be used by

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