Re: crc32 - couriuos question

"obar2" <obar2@xxxxxxxxxxxxxx> writes:


U¿ytkownik "Scott Fluhrer" <sfluhrer@xxxxxxxxxxxxx> napisa³ w wiadomo¶ci
news:1177709397.823652@xxxxxxxxxxxxxxxxxxxxxxxxxxx

"obar2" <obar2@xxxxxxxxxxxxxx> wrote in message
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Hello, I have hipotetical question.

Assume I have CRC32 of unknow string (I don't know nothing about string
only
that is string) which is e.g. "a505df1b".

Is the way to discover what string matches to this checksum ?

Here is a similar problem: I know that the sum of a list of numbers is
100.
I don't know anything about the list of numbers other than the sum. Is
there a way to discover the numbers in the list?

To address your problem, it's easy to find lots of strings that have this
CRC32; however, you wouldn't know which one is the one you're looking for.

Checking in loop every char and extending string or sth ?

Thanks

yes, but i would rather to know all possible list of the numbers which gives
sum 100.

so in my case i would know most of the strings which gives me such crc32. if
there is a plenty of this i need to know most of them...


Since the number of strings is infinite, you will never know "most of
them".
A better analogy would have been " I would rather [like] to know all
possible list[s] of numbers which sum and difference to 100."

Even for strings only 80 characters long ( a line length) there are about
10^183 such strings, which is more strings -- many many more strings-- than
there are atoms in the universe. Where are you going to write all of them?

A hash is not invertible.

.

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