Re: FW: Re: rsa/oaep

I believe that what we agreed before is to fix SHA-1 for using with MGF.

The reason that the same hash function is suggested to be used in RSASSA-PSS 
signature scheme is to against the weak-hash fuction substitute attack where the attacker
could forge a new signature from the given signature by using a weak hash function acceptable by the verifier in MGF. This attack can also be addressed by fixing a 
strong hash function (e.g. SHA-1) for use. 

In any case, RSA-OAEP is an encryption scheme so this type of attack doesn't make sense here.

Jiandong Guo
Phaos Technology