[xmlsec] Key Requirements

[Wouter]

Hi all,

I'm (still) working on some initial code that should start a full MS
Crypto API support package (unofrtunately the last 2 weeks I had a lot of
distractions :( .

While implementing signing support, I came across a function
(xmlSecMSCryptoSignatureSetKeyReq), its a xmlSecTransformSetKeyReqMethod,
that sets a xmlSecKeyReqPtr. The funcion is used in the signing process.
When creating a signature I can understand that a key is set, to create
the signature with, however this key requirements info I don't understand
exactly. What's it for and why is it set in the signing process?

Regards, Wouter