APGD(8)

NAME
apgd - server that generates several random passwords

SYNOPSIS
apgd [-r dictfile] [-a algorithm] [-C] [-L] [-S] [-N] [-m min_pass_len] [-x max_pass_len] [-n num_of_pass]

DESCRIPTION
apgd program is a server that supports Password Generation Protocol described in RFC972. It uses several password generation algorithms (currently two) and a built-in pseudo random number generator.

apgd is normally invoked by the Internet superserver (see inetd (8)) for requests to connect to the pwdgen port (pwdgen port is 129 according to RFC1700 ) as indicated by the /etc/services file (see services (5)).

Default algorithm is pronounceable password generation algorithm designed 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 online, 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 password. 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 algorithm described in Appendix C of ANSI X9.17 or RFC1750 with exception that it uses CAST 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.

apgd also have the ability to check generated password quality using dictionary. You can use this ability if you specify command-line option -r dictfile where dictfile is dictionary file name. In that dictionary 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. This check is case sensitive. For example, if you want to reject word 'root', you should insert in dictfile words: root, Root, RoOt, ... , ROOT. It is not the easiest way to check password quality, but it is the most powerful way. In future releases I plan to implement some other techniques to check passwords just to make life easier.

apgd has the ability log user password generation activity and internal debug information. It does this using
facility = daemon
    priority = info for user password generation activity logging
    priority = debug for internal debug information
See the syslogd(8) and syslog.conf(5) man pages for information on how to configure your syslog daemon.

OPTIONS

-S  use special symbol set (for random character password generation algorithm only)

-N  use numeral symbol set

-C  use capital symbol set

-L  use small letters symbol set (always present if pronounceable password generation algorithm is used)

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

-r dictfile
    check generated passwords for their appearance in dictfile

-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 6.

-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 8.

DEFAULT OPTIONS
apgd -a 0 -N -C -L -n 6 -m 6 -x 8

EXIT CODE
On successful completion of its task, apgd will complete with exit code 0. An exit code of -1 indicates an error occurred. Textual errors are written to the syslogd (8).

DIAGNOSTICS
All textual info is written to the syslogd(8).

FILES
None.

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

SEE ALSO
apg(1)

AUTHOR
Adel I. Mirzazhanov, <a-del@iname.com>
Project home page: http://www.adel.nursat.kz/apg/