1APGBFM(1) User Manual APGBFM(1)
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6 apgbfm - APG Bloom filter management program
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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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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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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
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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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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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100 None.
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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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108 apgd(8), apg(1)
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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)