Re: DES key parity bits. What is the correct story?

On 11-03-06 11:33 AM, Tom St Denis wrote:
On Mar 6, 12:07 pm, g...@xxxxxxxxxxxxx (Greg Rose) wrote:

Actually, in today's terminology, it's the *top* 7
bits of each byte that determines the key, and the
parity bit is the LSB. So using ASCII characters
as a key even more drastically reduces the
keyspace than one might think.

Sort of thing PKCS #5 was invented for.

Well now that you mention PKCS #5 and are talking about handling user provided passphrases, I might seek forgiveness in advance for hijacking this thread.

I am concerned about accepting user passphrases in JavaScript. As I understand it, JS does not provide a mechanism for clearing strings from memory. So if the user entered passphrase is ever stored as a string it is easily recoverable by forcing a dump of the browser's (or whatever is running the JS)'s core.

As I see it, there are three possible "fixes"

(1) Maybe I am wrong about JavaScript memory management and that if the string is inside some object, then manipulating the object can be used to get JS to genuinely forget the string.

(2) Find a way to take user input directly into an array instead of it ever being a string.

(3) Don't use JavaScript.

I would really hope to find a solution among (1) and (2).



Jeffrey Goldberg
I rarely read HTML or poorly quoting posts
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