Need to restore zeroed file

Roland Haeder roland at mxchange.org
Thu Jul 9 19:00:30 UTC 2015


Hello all,

bad news: One of my files in my storage got zeroed and I don't have the
old (working) URI or up-to-date backup (only from 2013).

I have currently written a brute-forcer which currently *should* test
all possibilities. Sure this needs massive improvement.

So I need to know something:

1) Is this URL pattern valid:

http://127.0.0.1:3456/file/URI%3ACHK%3A<key1>%3A<key2>%3A3%3A10%3A<num>/@@named=/<filename>

by:
<key1> = 26 Byte long character consisting of a BASE32 checksum
<key2> = 52 Byte long character consisting of a BASE32 checksum
<num>  = Random number from 0 to 99999
<filename> = The file's name without path

2) Is z_base_32_alphabet or rfc3548_alphabet taken as an alphabet?

3) Do I calculate this correctly?

26 length, each can have 32 different characters (key1)

This means 1*32^26 =
1361129467683753853853498429727072845824

possibilities?

And
1852673427797059126777135760139006525652319754650249024631321344126610074238976

possibilities for key2?

3) Do I *really* have to brute-force them all to find the correct URI?
Or can someone (I don't like to paste brute-forcer publicly) improve the
search algorithm?

Regards,
Roland

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