On 6/12/05, Ian G <[EMAIL PROTECTED]> wrote: > I'd like to take a password and expand it into > several keys. It seems like a fairly simple operation > of hashing the concatonatonation of the password > with each key name in turn to get each key. > > Are there any 'gotchas' with that? > > iang >
I guess you should use some scheme like PKCS #5 PBKDF2 scheme (password based key derivation function). The only difference between your idea and PBKDF2 is that the latter does a lot of hash rounds and is salted (I guess you pick key name to be static and not random, so they are not used as salts). Salting helps a bit against static precomputed hashes and techniques like rainbow tables. Ondrej Mikle --------------------------------------------------------------------- The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to [EMAIL PROTECTED]