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APG(1)				  User Manual				APG(1)

       apg - generates several random passwords

       apg  [-a	 algorithm]  [-M  mode]	 [-E char_string] [-n num_of_pass] [-m
       min_pass_len] [-x max_pass_len]	[-r  dictfile]	[-b  filter_file]  [-p
       min_substr_len]	[-s]  [-c  cl_seed] [-d] [-y] [-l] [-t]	[-k] [-q] [-h]

       apg generates several random passwords. It uses several password	gener-
       ation  algorithms  (currently  two) and a built-in pseudo random	number

       Default algorithm is pronounceable password  generation	algorithm  de-
       signed  by  Morrie  Gasser and described	in A Random Word Generator For
       Pronounceable Passwords National	Technical Information  Service	(NTIS)
       AD-A-017676.  The original paper	is very	old and	had never been put on-
       line, so	I have to use NIST implementation described in FIPS-181.

       Another algorithm is simple random character generation algorithm,  but
       it  uses	 four  user-defined symbol sets	to produce random password. It
       means that user can choose type of symbols that should appear in	 pass-
       word.  Symbol  sets are:	numeric	symbol set (0,...,9) , capital letters
       symbol set (A,...,Z) , small letters symbol set (a,...,z)  and  special
       symbols symbol set (#,@,!,...).

       Built-in	 pseudo	 random	number generator is an implementation of algo-
       rithm described in Appendix C of	ANSI X9.17 or RFC1750  with  exception
       that  it	 uses CAST or SHA-1 instead of Triple DES.  It uses local time
       with precision of microseconds (see  gettimeofday(2))  and  /dev/random
       (if available) to produce initial random	seed.

       apg  also  have	the  ability to	check generated	password quality using
       dictionary. You can use this ability if you  specify  command-line  op-
       tions  -r  dictfile  or	-b filtername where dictfile is	the dictionary
       file name and filtername	is the name of Bloom filter file. In that dic-
       tionary	you  may  place	words (one per line) that should not appear as
       generated passwords. For	example: user names, common  words,  etc.  You
       even can	use one	of the dictionaries that come with dictionary password
       crackers.  Bloom	filter file should be created with  apgbfm(1)  utility
       included	 in  apg  distribution.	In future releases I plan to implement
       some other techniques to	check passwords	(like pattern check)  just  to
       make life easier.

   Password generation modes options
       -a algorithm
	      use algorithm for	password generation.
	      0	- (default) pronounceable password generation
	      1	- random character password generation

       -n num_of_pass
	      generate num_of_pass number of passwords.	Default	is 6.

       -m min_pass_len
	      generate	 password   with   minimum  length  min_pass_len.   If
	      min_pass_len > max_pass_len then	max_pass_len  =	 min_pass_len.
	      Default minimum password length is 8.

       -x max_pass_len
	      generate	 password   with   maximum  length  max_pass_len.   If
	      min_pass_len > max_pass_len then	max_pass_len  =	 min_pass_len.
	      Default maximum password length is 10.

       -M mode
	      Use  symbolsets  specified  with	mode  for password generation.
	      mode is a	text string consisting of characters S,	s, N, n, C, c,
	      L, l. Where:

	      S	     generator must use	special	symbol set for every generated

	      s	     generator should use special symbol set for password gen-

	      N	     generator must use	numeral	symbol set for every generated

	      n	     generator should use numeral symbol set for password gen-

	      C	     generator must use	capital	symbol set for every generated

	      c	     generator should use capital symbol set for password gen-

	      L	     generator	must  use  small  letters symbol set for every
		     generated password	(always	present	if pronounceable pass-
		     word generation algorithm is used).

	      l	     generator	should	use small letters symbol set for pass-
		     word generation.

	      R,r    not supported any more. Use  -E  char_string  option  in-
	      mode can not be more than	4 characters in	length.

	      Usage of L, S, N,	C will slow down password generation process.

	      -M sncl or -M SNCL or -M Cn

       -E char_string
	      exclude  characters  in  char_string  from  password  generation
	      process (in pronounceable	password generation mode you  can  not
	      exclude  small  letters).	To include special symbols that	can be
	      recognized by shell (apostrophe, quotes, dollar sign,  etc.)  in
	      char_string use the backslashed versions.


	      Command  apg -a 1	-M n -n	3 -m 8 -E 23456789 will	generate a set
	      of passwords that	will look like this

	      Command apg -a 1 -M nc -n	3 -m 26	-E  GHIJKLMNOPQRSTUVWXYZ  will
	      generate a set of	passwords that will look like this

   Password quality control options
       -k     check every generated password using cracklib. To	use this abil-
	      ity you must enable cracklib support during programm building.

       -r dictfile
	      check generated passwords	for their appearance in	dictfile

       -b filter_file
	      check generated passwords	for their appearance  in  filter_file.
	      filter_file should be created with apgbfm(1) utility.

       -p min_substr_len
	      this  option tells apg(1)	to check every substring of the	gener-
	      ated password for	appearance in filter_file. If any of such sub-
	      strings  would  be found in the filter_file then generated pass-
	      word would be rejected and apg(1)	 will  generate	 another  one.
	      min_substr_len  specifies	 minimum  substring  length  to	check.
	      This option is active only if -b option is defined.

   Pseudo random number	generator options
       -s     ask user for random sequence for password	generation

       -c cl_seed
	      use cl_seed as a random seed for password	generation. I  use  it
	      when i have to generate passwords	in a shell script.

   Password output options
       -d     do  NOT use any delimiters between generated passwords. I	use it
	      when i have to generate passwords	in a shell script.

       -y     print  generated	passwords  and	crypted	 passwords  (see   man

       -q     quiet mode (do not print warnings)

       -l     spell  generated	passwords. Useful when you want	to read	gener-
	      ated password by telephone.
	      WARNING: Think twice before read your password by	phone.

       -t     print pronunciation for generated	pronounceable password

       -h     print help information and exit

       -v     print version information	and exit

       apg -a 0	-M sncl	-n 6 -x	10 -m 8	(new style)

       If you want to generate really secure passwords,	you should use	option
       -s.  To simplify	apg usage, you can write a small shell script. For ex-
       /usr/local/bin/apg -m 8 -x 12 -s
       [ end ]---->

       On successful completion	of its task, apg will complete with exit  code
       0.  An exit code	of -1 indicates	an error occurred.  Textual errors are
       written to the standard error stream.

       If /dev/random is not available,	apg will display a message about it.


       None.  If you've	found one, please send bug description to the author.

       apgd(8),	apgbfm(1)

       Adel I. Mirzazhanov, <>
       Project home page:

Automated Password Generator	  2003 Aug 04				APG(1)


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