Dr Stephen Henson wrote:
EKR wrote:
Dr Stephen Henson
<shenson(_at_)drh-consultancy(_dot_)demon(_dot_)co(_dot_)uk> writes:
I propose this option not because its the best but because its what the
two versions I've tested use: viz Netscape Messenger and Microsoft
Outlook.
Representatives from both companies are here. It seems to me best
to see what their opinions are.
As I've said before. I know they use X/8 on send. I'm not expecting
anyone to just take my word for it. I can demonstrate this to anyone who
doubts it.
In our S/MIME version 2 implementation we use X/8 on send, and accept physical
keys of any length on receive (up to the RC-2 limit). Early version of our
products did not accept the longer keys, but some S/MIME 2 implementations
generated them.
My personal preference would be to use an out of band way of communicating the
length if the wrapping mechanism did not implicitly include the length (perhaps
as a parameter to the wrapping mechanism). This helps me abstract way cipher
specific stuff from the PKCS 7 parsing code. Failing that either of the other
proposals (effective key size or fixed key size) are acceptable. both entail
about the same amount of cipher specific code.
bob
bob