[fpc-pascal] MD5 decryption?

[silvioprog]

2013/12/11 Ewald <ewald at yellowcouch.org>

>  Once upon a time, silvioprog said:
>
>  2013/12/11 Ewald <ewald at yellowcouch.org>
>
>  Go to: http://md5decryption.com
> In "Please input the MD5 hash that you would like to be decrypted:" field,
> put: 7db4a8dae498d1b4686ebd1f79326602
> See the result in "Decrypted Text:" field.
>
> Yes, I've seen the  site, what they probably do is a reverse lookup in a
> table, but it cannot be called `decryption`. Encryption is two way: an
> output can be converted back to the original input. This is not the case
> with a hashing function. Take for example a very simple function that xor's
> all input bytes together (with MD5 it boils down to the same, albeit a bit
> more complex). If I give you the output $F0, how do you know what was the
> original input? The answer is you don't. It could be [$80 $70] as well as
> it could have been [$C0 $FF $30 $FF]...
>
> While both algorithm types (encryption and hashing) are related (the above
> xor example classified as a checksum, whereas xor encryption also exists),
> they are definitly not the same.
>
> --
> Ewald
>
>
Nice explanation, thanks! (y)

-- 
Silvio Clécio
My public projects - github.com/silvioprog
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