Are there sha 512 rainbow tables available for download or what kind of dimensions and processing power would be required to generate them?
closed as off-topic by Ayrx, TildalWave, Adi, Scott Pack, Iszi Oct 21 '13 at 15:43
This question appears to be off-topic. The users who voted to close gave this specific reason:
- "Questions seeking product recommendations are off-topic as they become obsolete quickly. Instead, describe your situation and the specific problem you're trying to solve." – Ayrx, TildalWave, Adi, Scott Pack
Possibly, but given their size - much more likely to download a generation tool and a word pattern list.
Rainbow tables are a carefully comprised collection of dictionary words and probable combinations in order to save on space.
A rainbow table sufficient for alphanumerical passwords of up to 9 characters is 864 GB in size. A rainbow table for this level entropy will be the size for any hash (MD5, SHA-1, SHA-512, etc) as rainbow tables are actually hashes hashed down to the entropy of the passwords (say, 254). The uniformity distribution requirement of the cryptographic hash makes this possible, but hashes with much larger bit space than the password entropy will have some collisions when hashed down to lower entropy level. Hence the "success rate" column of the rainbow table.
As 900 GB is tolerable for a determined hacker and as people that use alphanumeric passwords less than 10 characters exist, websites will use random salting to foil a rainbow table plus often use a slow key derivation function like PBKDF2 or scrypt.
None of these truly stop matching of a hash to password in a (much slower "sparse" meta-mega) rainbow table if the attacker got their hands on the server's user table. Which is why not using the same password across multiple sites is important.