On Thu, Nov 08, 2012 at 03:22:24PM -0800, Morlock Elloi wrote:
However, if you use asymmetric crypto (say, 1024 or 2048-bit RSA), give
only public key(s) to encrypting flows, and reserve the secret key(s) for
modules that need the actual plaintext access (a rare situation in
practice), then:

Do you do any padding?  If not you might be vulnerable to multiplication
because:

RSA(a)*RSA(b) == RSA(a*b)

and if you are doing padding (eg with random inputs if any seeded by the
plaintext and a fixed secrete seed), then you need rigorously verify the
padding on decrypt or the padding may not defend against multiplication.

Adam
_______________________________________________
cryptography mailing list
[email protected]
http://lists.randombit.net/mailman/listinfo/cryptography

Reply via email to