


      CCCCRRRRYYYYPPPPTTTT((((1111))))                    ((((UUUUNNNNIIIIXXXX 5555....0000))))                   CCCCRRRRYYYYPPPPTTTT((((1111))))



      NNNNAAAAMMMMEEEE
           crypt - encode/decode

      SSSSYYYYNNNNTTTTAAAAXXXX
           ccccrrrryyyypppptttt [ password ]

      DDDDEEEESSSSCCCCRRRRIIIIPPPPTTTTIIIIOOOONNNN
           CCCCrrrryyyypppptttt encrypts and decrypts files according to a password.

           CCCCrrrryyyypppptttt reads from the standard input and writes on the
           standard output.

           The _p_a_s_s_w_o_r_d is a key that selects a particular
           transformation.  If no _p_a_s_s_w_o_r_d is given, _c_r_y_p_t demands a
           key from the terminal and turns off printing while the key
           is being typed in.  _C_r_y_p_t encrypts and decrypts with the
           same key:

                crypt key <clear >cypher
                crypt key <cypher | pr

           will print the clear.

           Files encrypted by _c_r_y_p_t are compatible with those treated
           by the editor _e_d in encryption mode.

           The security of encrypted files depends on three factors:
           the fundamental method must be hard to solve; direct search
           of the key space must be infeasible; ``sneak paths'' by
           which keys or clear text can become visible must be
           minimized.

           _C_r_y_p_t implements a one-rotor machine designed along the
           lines of the German Enigma, but with a 256-element rotor.
           Methods of attack on such machines are known, but not
           widely; moreover the amount of work required is likely to be
           large.

           To discourage a spy from trying all combination of keywords
           to read your file, the transformation of files is
           deliberately slow.  But a keyword of three lowercase
           characters would be quite easy to crack in a short time, so
           make your keywords longer.

           To prevent your keyword from showing up in the command field
           of the ps(1) output, ccccrrrryyyypppptttt destroys the record of the
           keyword immediately upon execution.

           The choice of keys and key security are the most vulnerable
           aspect of _c_r_y_p_t.

           You may encryt a file twice, with two different keywords.



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      CCCCRRRRYYYYPPPPTTTT((((1111))))                    ((((UUUUNNNNIIIIXXXX 5555....0000))))                   CCCCRRRRYYYYPPPPTTTT((((1111))))



           According to federal export regulations, ccccrrrryyyypppptttt is not
           available in the International versions of the Ridge
           Operating System.

      FFFFIIIILLLLEEEESSSS
           /dev/tty  for typed key

      SSSSEEEEEEEE AAAALLLLSSSSOOOO
           ed(1), makekey(1).

      BBBBUUUUGGGGSSSS
           If output is piped to _n_r_o_f_f and the encryption key is _n_o_t
           given on the command line, _c_r_y_p_t can leave terminal modes in
           a strange state (see _s_t_t_y(1)).
           If two or more files encrypted with the same key are
           concatenated and an attempt is made to decrypt the result,
           only the contents of the first of the original files will be
           decrypted correctly.





































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