I am working on a cloud-based solution and I would like to encrypt / decrypt the data locally using either a SmartCard or local Machine certificate. I'm hoping to do this in Javascript, but may resort to Silverlight, ActiveX, or Flash (in order of preference)
My idea is to use this in conjunction with broadcast encryption to allow for concurrent access to encrypted data in the cloud.
Is there an API common among smartcard vendors that exposes itself to the browser? (marked safe for scripting)
Is there any chance of creating a cross platform solution?