4 ms·
Not all operations are reversible, which makes it difficult to work out a simple inverse. Of course you could work backwards to find out which inputs could lead
by contravariant 10y ago
Not all operations are reversible, which makes it difficult to work out a simple inverse. Of course you could work backwards to find out which inputs could lead to a particular result, but this set of possible inputs would grow rapidly as you work your way back through the algorithm, making it nigh impossible to work out the original message, even if you have some idea what it's supposed to look like.
Of course this is assuming that the hash algorithm doesn't have any weaknesses you could exploit.
- dorfsmay 10y ago> Of course you could work backwards to find out which inputs could lead to a particular result AKA rainbow tables, which explains why it is important not to use just a single word from the dictionary as a password. https://en.wikipedia.org/wiki/Rainbow_table https://en.wikipedia.org/wiki/Rainbow_table
- jessaustin 10y agoAs explained in your link, rainbow tables make salts important. Imposing arbitrary requirements on users is misguided.