OASIS ebXML Messaging Services TC

RE: [ebxml-msg] Sign and Encrypt

  • 1.  RE: [ebxml-msg] Sign and Encrypt

    Posted 11-05-2001 02:34
    Hi Ralph, Actually, you asked me to take minutes in London, although, I confess, I gave up with all the shouting. It is incorrect from a security point of view to encrypt before signing. One thing about security, if you don't get it right to start with, it often never gets right. I remember, in London, all the work you and Chris did in the hotel lobby to create section 12 (now appendix C) -- thank you, it was much appreciated. I also remember some discussion when you presented your work. Without rejecting your work, we specifically decided to support only profiles 0 & 1. We did not make any decision on confidentiality other than to support XMLEncryption when it appears and allow S/MIME (and other current technologies) until then. Unfortunately, we can't just leave this to the implementors. We cannot just decide that we know better than all the security experts in the industry and go off our own way. First sign, then encrypt. This is the way it works. Unfortunately, we have put ourselves in a difficult situation. We are trying to use XML functions (XMLdSig, XMLEncryption) for non-XML constructs. The XMLdSig authors specifically rejected non-XML constructs while still allowing the use of bit-stream type data. We are attempting to use these specs where they were never intended. This is not necessarily bad since these specs give us some flexibility we might not otherwise have, but this means we must specifically specify how these non-XML constructs are to be supported, both now for dSig and later for XMLEncryption. Thus far we have not done that. We are attempting to work this out now. If, as you say, we made such a decision in the past, it is time to correct it now. Regards, David Fischer Drummond Group.