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Section: UNIX Reference Manual (1) Updated: 1998 February 9
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makepasswd - generate and/or encrypt passwords  


makepasswd [ --chars N ] [ --clearfrom file ] [ --count N ] [ --crypt | --nocrypt | --crypt-md5 ] [ --cryptsalt N ] [ --help ] [ --maxchars N ] [ --minchars N ] [ --randomseed N ] [ --rerandom N ] [ --repeatpass N ] [ --string string ] [ --verbose | --noverbose ]  


makepasswd generates true random passwords by using the /dev/urandom feature of Linux, with the emphasis on security over pronounceability. It can also encrypt plaintext passwords given on the command line.  


--chars N
Generate passwords with exactly N characters (do not use with options --minchars and --maxchars).
--clearfrom FILE
Use password from FILE instead of generating passwords. Requires the --crypt or the --crypt-md5 options; may not be used with these options: --chars, --maxchars, --minchars, --count, --string, --nocrypt. Trailing newlines are removed but other white space is not.
--count N
Produce a total of N passwords (the default is one).
Produce encrypted passwords.
Produce encrypted passwords using the MD5 digest (hash) algorithm.
--cryptsalt N
Use crypt() salt N, a positive number <= 4096. If random seeds are desired, specify a zero value (the default).
Ignore other operands and produce only a help display.
--maxchars N
Generate passwords with at most N characters (default = 10).
--minchars N
Generate passwords with at least N characters (default = 8).
Do not encrypt the generated password(s) (the default).
Display no labels on output (the default).
--randomseed N
Use random number seed N, between 0 and 2^32 inclusive. A zero value results in a real-random seed. This generates much less secure passwords than the default; not only does it generate predictable passwords due to the fixed seed, but the range of available seeds is 32 bits rather than the default of 256 bits, and cannot be changed without breaking expectations of previous users of this option. If possible, do not use this option.
--rerandom N
Set the random seed value every N values used. Specify zero to use a single seed value (the default). Specify one to get true-random passwords, though note that doing this too frequently will deplete the supply of entropy available in Linux's entropy pool.
--repeatpass N
Use each password N times (4096 maximum, --crypt must be set and --cryptsalt may not be set).
--string STRING
Use the characters in STRING to generate random passwords.
Display labelling information on output.


makepasswd was originally part of the mkircconf program used to centrally administer the Linux Internet Support Cooperative IRC network. It may potentially be of use in any situation where passwords must be secure and need not be memorized by humans.

Colin Watson modified it to use OpenSSL's pseudo-random number generator.  


Copyright (c) 1997-1998 by lilo <>. All rights are reserved by the author. This program may be used under the terms of version 2 of the GNU Public License.  






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Time: 21:14:48 GMT, April 16, 2011