Password Dictionary File/ Each Entry is 2 or 3 Words Concatenated?

Password Dictionary File/ Each Entry is 2 or 3 Words Concatenated?
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Password Dictionary File/ Each Entry is 2 or 3 Words Concatenated? poster3814 05-01-2007
Posted by Moe Trin on May 11, 2007, 3:50 pm
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On Fri, 11 May 2007, in the Usenet newsgroup comp.security.misc, in article


>> Have you etimated the size of your new dictionary? Just start with
>>100 000 words, that gives us 10 000 000 000 on a two word list and
>>1 000 000 000 000 000 for a three word list, just say a word is 8
>>letters long, that gives us a mean size of 24 letters so we need
>>approximatly 24 10^15 or 24 000 TeraBytes. And that's a big hard
>>drive ;-)
>
>The original posting imposed fairly strict limits on the total
>length of the concatenated word. The original posting also implied
>that the length limit was not through truncation -- that the two
>or three words together had to add up to at most the size limit.

The original post said:

Are there password dictionary files whose entries aren't just single
words but rather 2 or 3 words of maybe 6 letters or less concatenated?
For example, "they red solids" are 3 words of 6 letters or less that
concatenated would be "theyredsolids." Are there such dictionary files
downloadable, or is there a relatively easy way one could be created?

[compton ~]$ size.of.words /usr/local/share/dict/web2
Source /usr/local/share/dict/web2 has 235882 words
. 52 ........ 29988
.. 160 ......... 32403
... 1420 .......... 30878
.... 5272 ........... 26013
..... 10228 ............ 20462
...... 17705 more than 12 char 37432
....... 23869
[compton ~]$ echo "52+160+1420+5272+10228+17705" | bc
34837
[compton ~]$ echo "34837^3" | bc
42278760414253
[compton ~]$

That's still quite a few words to mash together ;-)

/usr/local/share/dict/web2 is the "Webster's Second International"
available through any search engine

Old guy

Posted by Benoit Leraillez on May 12, 2007, 3:00 pm
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> [compton ~]$ echo "34837^3" | bc
> 42 278 760 414 253

Si je ne m'abuse, on a là le nombre de possibilités. Il suffit
ensuite de multiplier le tout par la longueur moyenne d'une string
(mettons 12) et on obtiens : 507 345 124 971 036 octets soit un eu plus
d'un demi tera. Même s'il est vrai qu'on a pas intérêt à stocker tout ça
mais les strings et calculer les triplets à la volée, 42 * 10^12 cela
prend du temps à tester.

Si on est capable d'en tester un million à le seconde (il faut bien
une base) il faut quand même 42 millions de secondes pour y arriver et à
3600 secondes de l'heure cela nous fait pas loin d'une année et demi
pour arriver à bout. Maintenant il est vrai qu'on a une chance sur deux
de trouver le mot de passe en 250 jours ;-)

--
Les gens sans humour manquent de sérieux.

Posted by poster3814 on May 20, 2007, 6:36 pm
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Moe Trin wrote:
> On Fri, 11 May 2007, in the Usenet newsgroup comp.security.misc, in article
>
>
>>> Have you etimated the size of your new dictionary? Just start with
>>> 100 000 words, that gives us 10 000 000 000 on a two word list and
>>> 1 000 000 000 000 000 for a three word list, just say a word is 8
>>> letters long, that gives us a mean size of 24 letters so we need
>>> approximatly 24 10^15 or 24 000 TeraBytes. And that's a big hard
>>> drive ;-)
>> The original posting imposed fairly strict limits on the total
>> length of the concatenated word. The original posting also implied
>> that the length limit was not through truncation -- that the two
>> or three words together had to add up to at most the size limit.
>
> The original post said:
>
> Are there password dictionary files whose entries aren't just single
> words but rather 2 or 3 words of maybe 6 letters or less concatenated?
> For example, "they red solids" are 3 words of 6 letters or less that
> concatenated would be "theyredsolids." Are there such dictionary files
> downloadable, or is there a relatively easy way one could be created?
>
> [compton ~]$ size.of.words /usr/local/share/dict/web2
> Source /usr/local/share/dict/web2 has 235882 words
> . 52 ........ 29988
> .. 160 ......... 32403
> ... 1420 .......... 30878
> .... 5272 ........... 26013
> ..... 10228 ............ 20462
> ...... 17705 more than 12 char 37432
> ....... 23869
> [compton ~]$ echo "52+160+1420+5272+10228+17705" | bc
> 34837
> [compton ~]$ echo "34837^3" | bc
> 42278760414253
> [compton ~]$
>
> That's still quite a few words to mash together ;-)
>
> /usr/local/share/dict/web2 is the "Webster's Second International"
> available through any search engine
>
> Old guy

To be honest, I was thinking there might be a variety of dictionary
files out there of this type that aren't "complete" dictionaries. For
example, ones with only "everyday" words, so to speak, or ones with no
scientific terms, or no proper nouns, no numerals, etc. I thought it
feasible that such a file would be of a manageable size.

I was also thinking that if there were programs that do what I was
asking that perhaps the user could select criteria, such as only
concatenating 2 words of 5 letters each. Then the user could run it
again later concatenating 2 words of 4 letters each, etc.
--
Please respond to the newsgroup only. Email sent to this account goes
unread.

Posted by Moe Trin on May 21, 2007, 3:44 pm
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On Sun, 20 May 2007, in the Usenet newsgroup comp.security.misc, in article

>Moe Trin wrote:

>> [compton ~]$ size.of.words /usr/local/share/dict/web2
>> Source /usr/local/share/dict/web2 has 235882 words
>> . 52 ........ 29988
>> .. 160 ......... 32403
>> ... 1420 .......... 30878
>> .... 5272 ........... 26013
>> ..... 10228 ............ 20462
>> ...... 17705 more than 12 char 37432
>> ....... 23869
>> [compton ~]$ echo "52+160+1420+5272+10228+17705" | bc
>> 34837
>> [compton ~]$ echo "34837^3" | bc
>> 42278760414253
>> [compton ~]$
>>
>> That's still quite a few words to mash together ;-)
>>
>> /usr/local/share/dict/web2 is the "Webster's Second International"
>> available through any search engine

>To be honest, I was thinking there might be a variety of dictionary
>files out there of this type that aren't "complete" dictionaries. For
>example, ones with only "everyday" words, so to speak, or ones with no
>scientific terms, or no proper nouns, no numerals, etc. I thought it
>feasible that such a file would be of a manageable size.

The size of a dictionary is nearly always an advertising gimmick. I have
two paperback dictionaries on this desk with the number of definitions
prominently displayed as if more is better. A more commonly used
computer word list (not a dictionary, because it lacks definitions) has

[compton ~]$ size.of.words /usr/share/dict/words
Source /usr/share/dict/words has 45402 words
. 0 ...... 6175 ........... 3069
.. 49 ....... 7370 ............ 1881
... 536 ........ 7075 ............. 1136
.... 2238 ......... 6086 .............. 545
..... 4179 .......... 4592 15 or more char 471
[compton ~]$

which (assuming English is your original language) is more like what you
would be using in normal conversation. In the 1950s, international short
wave radio was an important tool used to exchange news, ideas and culture
among nations. The official USA service was The Voice Of America, which
(at the peak in the 1960s) had dozens of transmitters broadcasting 24/7
in dozens of languages. ONE OF those languages was called "Special English"
and used a vocabulary of just 1500 words, for people who used English as a
second or third language. While they did speak slower, even that limited
number of words didn't make the language seem out of place for a primary
English speaker.

>I was also thinking that if there were programs that do what I was
>asking that perhaps the user could select criteria, such as only
>concatenating 2 words of 5 letters each. Then the user could run it
>again later concatenating 2 words of 4 letters each, etc.

I don't know why one would be needed, as this is trivial to accomplish
using virtually any programming language from BASIC to perl to ruby to
you name it. Creating a dictionary of such combinations is pretty much a
waste of CPU cycles and disk-space. Using the word-list noted above, there
are 2238 words of four characters, and 4179 of five. Any two five letter
words, and you have about 4179^2 or 1.75e6 results. Ignoring case, and
using a 5 bit (Baudot) alphabet, storing those strings would require over
a hundred megabytes of space - closer to 180 megabyts using ASCII.

To what end? Do you want to make a book that takes these words and
creates a password hash for each one? For the normal UNIX 'crypt'
mechanism which adds two 'salt' characters to "spice up" (vary) the
hashing algorithm, those 1.75e6 passwords become 7.15e10 different
13 character result hashes which would take 930 Gigabytes to store in
ASCII. Allowing the password to contain upper and lower case multiplies
the storage space needed by several orders of magnitude.

Old guy

Posted by poster3814 on June 5, 2007, 3:48 pm
If you were  Registered and logged in, you could reply and use other advanced thread options
Moe Trin wrote:
> On Sun, 20 May 2007, in the Usenet newsgroup comp.security.misc, in article
>
>> Moe Trin wrote:
>
>>> [compton ~]$ size.of.words /usr/local/share/dict/web2
>>> Source /usr/local/share/dict/web2 has 235882 words
>>> . 52 ........ 29988
>>> .. 160 ......... 32403
>>> ... 1420 .......... 30878
>>> .... 5272 ........... 26013
>>> ..... 10228 ............ 20462
>>> ...... 17705 more than 12 char 37432
>>> ....... 23869
>>> [compton ~]$ echo "52+160+1420+5272+10228+17705" | bc
>>> 34837
>>> [compton ~]$ echo "34837^3" | bc
>>> 42278760414253
>>> [compton ~]$
>>>
>>> That's still quite a few words to mash together ;-)
>>>
>>> /usr/local/share/dict/web2 is the "Webster's Second International"
>>> available through any search engine
>
>> To be honest, I was thinking there might be a variety of dictionary
>> files out there of this type that aren't "complete" dictionaries. For
>> example, ones with only "everyday" words, so to speak, or ones with no
>> scientific terms, or no proper nouns, no numerals, etc. I thought it
>> feasible that such a file would be of a manageable size.
>
> The size of a dictionary is nearly always an advertising gimmick. I have
> two paperback dictionaries on this desk with the number of definitions
> prominently displayed as if more is better. A more commonly used
> computer word list (not a dictionary, because it lacks definitions) has
>
> [compton ~]$ size.of.words /usr/share/dict/words
> Source /usr/share/dict/words has 45402 words
> . 0 ...... 6175 ........... 3069
> .. 49 ....... 7370 ............ 1881
> ... 536 ........ 7075 ............. 1136
> .... 2238 ......... 6086 .............. 545
> ..... 4179 .......... 4592 15 or more char 471
> [compton ~]$
>
> which (assuming English is your original language) is more like what you
> would be using in normal conversation. In the 1950s, international short
> wave radio was an important tool used to exchange news, ideas and culture
> among nations. The official USA service was The Voice Of America, which
> (at the peak in the 1960s) had dozens of transmitters broadcasting 24/7
> in dozens of languages. ONE OF those languages was called "Special English"
> and used a vocabulary of just 1500 words, for people who used English as a
> second or third language. While they did speak slower, even that limited
> number of words didn't make the language seem out of place for a primary
> English speaker.
>
>> I was also thinking that if there were programs that do what I was
>> asking that perhaps the user could select criteria, such as only
>> concatenating 2 words of 5 letters each. Then the user could run it
>> again later concatenating 2 words of 4 letters each, etc.
>
> I don't know why one would be needed, as this is trivial to accomplish
> using virtually any programming language from BASIC to perl to ruby to
> you name it. Creating a dictionary of such combinations is pretty much a
> waste of CPU cycles and disk-space. Using the word-list noted above, there
> are 2238 words of four characters, and 4179 of five. Any two five letter
> words, and you have about 4179^2 or 1.75e6 results. Ignoring case, and
> using a 5 bit (Baudot) alphabet, storing those strings would require over
> a hundred megabytes of space - closer to 180 megabyts using ASCII.
>
> To what end? Do you want to make a book that takes these words and
> creates a password hash for each one? For the normal UNIX 'crypt'
> mechanism which adds two 'salt' characters to "spice up" (vary) the
> hashing algorithm, those 1.75e6 passwords become 7.15e10 different
> 13 character result hashes which would take 930 Gigabytes to store in
> ASCII. Allowing the password to contain upper and lower case multiplies
> the storage space needed by several orders of magnitude.
>
> Old guy

Eesh. That's a lot of data.

Your post seems to make a lot of sense, and I appreciate your time in
replying. As it seems the question I was wondering about would prove to
be a big mess of a solution, and it's really not that big a deal to me
anyway, I don't want to waste anyone's time further with it.

Thanks again for everyone's time and effort.
--
Please respond to the newsgroup only. Email sent to this account goes
unread.

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