HELP, CRC32
 

I need someone skills here

if i got a CRC32 of $44AA4E6A

and i next a text string that crc32's to that
using only numbers and letters

how can i work it backwards?

if someone knows how, can they post some text...

thanks!

mitch

google for "CRC32" + "reversing" :D

Hey.....

That's my line. :D

Regards,

:D
AqHI0F20A631-UFO
58RJ87818080-UFO
Ngkr6CC75340-UFO
1V2kE87C7340-UFO
zmQi9CD75500-UFO
dQToB1F78D20-UFO
gKCu6AFDFB00-UFO
.
.
.
all these string CRC32=BB55B195

CRC32 is NOT a one-way HASH like MD5...etc...:)

I ofcourse googled!!!

i found the reversing... but was still at losss

I wrote a small vb ap, to randomly generate text strings
and CRC32 them...

figuring id get one soon.

it ran for 20 hours, nadda

FiNALSErAPH, can you make me a string for my crc32?

CRC32 = 44AA4E6A


mitch

20 hours? Are you sure your algorithm (or the random generator) is correct?

Long time ago, I wrote a bruteforcer for CRC32 (even before I calculated how to compute it directly :D) - and on Pentium 3 1.5 GHz is takes slighly over a minute to check the 2^32 possibilities.
It generates binary data (not just "numbers and letters")... but a simple algorithm that tries random texts should be about the same, i.e. getting the result in about half a time (in average).

1f1hBEFF6171-UFO
C3NQD2F41542-UFO
44lY10712D92-UFO
MBU120C3A3A3-UFO
5SXM733B9FD0-UFO
85Nr1D408CF0-UFO
syxb454ACB60-UFO
.
.
.
0xBB55B195 ^ 0xFFFFFFFF = 0x44AA4E6A

^_^

read this tut...

Title : CRC and how to Reverse it
Author : Anarchriz/DREAD
Release Date : 29 april 1999 (last modification 30 april 1999)
Difficulty : beginner to advanced
Target : CRC algorithm
Tools : QEdit 2.1 (the best!) & Wordpad & some CRC progs
Description : A CRC Tutorial & The c00l way to Reverse CRC


CRC and how to Reverse it
.
.
.

Knocked this out a while ago, and should do what you want, more or less.
It isn't base16 so you may want to adjust the src and recompile.

arz...

Thanks FiNALSErAPH


im not 100% sure what you mean by

0xBB55B195 ^ 0xFFFFFFFF = 0x44AA4E6A

yes that statement above is true

but why did u calculate bb55b195's strings 1 first time?

bear with me... for being blind here...

mitch