1APGBFM(1)                         User Manual                        APGBFM(1)
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NAME

6       apgbfm - APG Bloom filter management program
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SYNOPSIS

10       apgbfm -f filter -n numofwords [-q] [-s]
11       apgbfm -f filter -d dictfile [-q] [-s]
12       apgbfm -f filter -a word [-q]
13       apgbfm -f filter -A dictfile [-q]
14       apgbfm -f filter -c word [-q]
15       apgbfm -f filter -C dictfile [-q]
16       apgbfm -i filter
17       apgbfm [-v] [-h]
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DESCRIPTION

20       apgbfm is used to manage Bloom filter that is used to restrict password
21       generation in APG pasword generation software. Usage of the Bloom  fil‐
22       ter  allows  to  speed up password check for large dictionaries and has
23       some other benefits.
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25       The idea to use Bloom filter for that purpose is came from the descrip‐
26       tion  of the OPUS project OPUS: Preventing Weak Password Choices Purdue
27       Technical Report CSD-TR 92-028 writen by Eugene H. Spafford.
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29       You can obtain this article from:
30       http://www.cerias.purdue.edu/homes/spaf/tech-reps/9128.ps
31       It has very nice description of Bloom filter and  it's  advantages  for
32       password checking systems.
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34       In simple words, apgbfm generates n hash values for every word and sets
35       corresponding bits in filter file to 1. To check the word apgbfm gener‐
36       ates  the  same hash functions for that word and if all n corresponding
37       bits in filter file are set to 1 then it suppose that  word  exists  in
38       dicionary.  apgbfm uses SHA-1 as a hash function.
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40       apgbfm can be used as standalone utility, not only with apg, or apgd.
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42       WARNING !!!
43              Filter  file  format  can  be changed in the future. I'll try to
44              make file formats compatible but i can not guaranty this.
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46       WARNING !!!
47              apgbfm may slow down your computer during filter creation.
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OPTIONS

50       -f filter
51              use filter as the name for Bloom filter filename.
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53       -i filter
54              print information about filter.
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56       -n numofwords
57              create new empty filter for numofwords number of  words.  Useful
58              when you want to fill filter dynamicaly.
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60       -d dictfile
61              create  new  filter  from dictfile. It may take a lot of time to
62              generate filter from a big dictionary. In  that  dictionary  you
63              may  place words (one per line) that should not appear as gener‐
64              ated passwords.  For example: user names common words, etc.  You
65              even  can  use one of the dictionaries that come with dictionary
66              password crackers.  This check is case sensitive.  For  example,
67              if you want to reject word 'root', you should insert in dictfile
68              words: root, Root, RoOt, ... , ROOT.  To indicate  that  program
69              is  working  apgbfm prints dot for every 100 words added in dic‐
70              tionary.
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72       -a word
73              add word to the filter.
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75       -A dictfile
76              add all words from dictfile to the filter. To indicate that pro‐
77              gram  is  working apgbfm prints dot for every 100 words added in
78              dictionary.
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80       -c word
81              check word for appearance in the filter.
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83       -C dictfile
84              check every word from dictfile for appearance in the filter.
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86       -q     quiet mode.
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88       -s     create new filter in case-insensitive mode.
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90       -v     print version information.
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92       -h     print help information.
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EXIT CODE

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

100       None.
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BUGS

103       None.  If you've found one, please send bug description to the author.
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105       This man page is Alpha too.
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SEE ALSO

108       apgd(8), apg(1)
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AUTHOR

111       Adel I. Mirzazhanov, <a-del@iname.com>
112       Project home page: http://www.adel.nursat.kz/apg/
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116Automated Password Generator      2003 Jun 19                        APGBFM(1)
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