Re: [pkcs11] CK_ULONG considered harmful?

[Valerie Anne Fenwick <valerie.fenwick@oracle.com>]

On 05/20/13 02:46 PM, Chris Zimman wrote:
> > I think the right thing to do here is for me to withdraw this comment (unless someone comes up with an actual problem encountered).
>
> I don't think withdrawing it is necessary -- it's just something that might be better left until 3.0.  Having non-exact specified types is bad, and it can lead to a wide variety of problematic situations.  The most simple example is where a token and interface disagree on the size of a CK_ULONG.  For example, a token that's internally 64 bit and can support 64 and 32 bit clients:  If the 64 bit client creates an object that contains an item with a 64 bit CK_ULONG value inside of it for whatever reason, there's no way for the 32 bit client to understand it since it may contain a value greater than 32 bits.  Both things have been operating legally.  Also, what is a 64 bit client supposed to do if it tries to submit a value to a 32 bit token in a CK_ULONG that exceeds 32 bits?  The token will have to reject it, but there aren't even error codes to handle all the cases.  Granted, most values fit into a 32 bit size, but that's more coincidence vs. good design.

I agree with this, and what Darren brought up earlier: in 3.0, let's
use explicit types from the get-go and save these heartaches later
on down the line.

Valerie
--
Valerie Fenwick, http://bubbva.blogspot.com/ @bubbva
Solaris Cryptographic Technologies, Manager, Oracle Corporation
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