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nettle-pbkdf2(1)


NAME

   nettle-pbkdf2 - Command-line password-based key derivation tool.

SYNOPSIS

   nettle-pbkdf2 [OPTIONS] SALT

DESCRIPTION

   This  manual  page  documents  briefly the nettle-pbkdf2 command.  This
   manual page was written for the Debian GNU/Linux  distribution  because
   the original program does not have a manual page.

   nettle-pbkdf2  is  a  front-end for Nettle's PBKDF2 (Password-Based Key
   Derivation Function 2) implementation. PBKDF2 applies  a  pseudo-random
   function  to a passphrase together with a salt, producing a derived key
   of arbitrary length. By iterating the process many times,  feeding  the
   output  of each round as the input of the next, brute-force cracking of
   the password is made to take correspondingly longer time. The use of  a
   salt  makes  it  harder  to  use  dictionaries  or  rainbow  tables. As
   computers become  more  powerful,  the  number  of  iterations  can  be
   increased without changing the rest of the algorithm.

   The pseudo-random function used by this tool is currently HMAC-SHA256.

   The  password is read from standard input and the resulting derived key
   is written to standard output  in  groups  of  16  hexadecimal  digits,
   unless  the --raw option is used. The salt and number of iterations are
   not included in the output.

OPTIONS

   This program follows the usual  GNU  command  line  syntax,  with  long
   options  starting  with  two  dashes  (`-').   A  summary of options is
   included below.

   -l, --length=length
          Desired output length in octets.

   --raw  Output derived key in raw binary format.

   --hex-salt
          Specifies that SALT is provided in hexadecimal format.

   --help Show summary of options.

   -V, --version
          Show version of program.

SEE ALSO

   mkpasswd(1), https://en.wikipedia.org/wiki/PBKDF2

AUTHOR

   This  manual  page  was   originally   written   by   Magnus   Holmgren
   <holmgren@debian.org>, for the Debian GNU/Linux system (but may be used
   by others).



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