Thanks Nelson for explaining this. I also understand your worries regarding what to sign and I would be very dishonest if I said I have "solved" it. In fact, my design doesn't even address this issue (!) except that if of course builds on the assumption that at least the "viewer" works as expected.
Now, why don't I feel that this is a huge limitation? First a legal issue. Based on *actual* court cases you can indeed be convicted based on IP addresses if you are found downloading forbidden data. I.e. digital signatures are simply a stronger evidence. Then a practical issue. If a crooked site asks you to sign a form that in some way is camouflaged (using overlaid HTML) into something else, the question is really what the crooked site can do with that unless the crooked site actually is a genuine representative of your government, bank, or employer. That is, in spite of all the legal "trauma" associated with signatures, authentication is actually MUCH more critical because there is nothing to repudiate in the case somebody cracked your medical file etc. You may be interested (still awake?) knowing that payment operations in brick-and-mortar shops is ultimately the most important application for the suggested scheme. Since this list doesn't really work with payments, I won't bore you to death with how this is supposed to work, but it does! Anders If you really want to test Web Signing you can try this proxy setup http://upi-using-service.webpki.org/IncomeDeclaration use PIN 1234 :-) ----- Original Message ----- From: "Nelson Bolyard" <[EMAIL PROTECTED]> To: "mozilla's crypto code discussion list" <[email protected]> Sent: Thursday, November 20, 2008 00:07 Subject: Web signing? Eddy Nigg wrote: > On 11/19/2008 05:52 PM, Anders Rundgren: >> In the meantime, wouldn't it be of some value if Mozilla tried to >> satisfy a PKI- >> related activity that in number of users, already is much bigger than >> S/MIME, >> i.e. the concept of "Web Signing"? > > What is this supposed to be? Perhaps I missed it? I think this is a reference to the action historically called "form signing" (or more accurately "form post signing") in Mozilla. It's a way to sign the data being sent in to a web server with the user's private key, as the data is being sent. Mozilla implements this with a javascript extension known as "crypto.signtext". I think IE implements it with an ocx (an Active-X module). There doesn't seem to be any standard for a way make this work that is common to all browsers. NSS provides the necessary crypto code. What's missing is the definition of the way (syntax) by which to invoke it in the browser. If I recall correctly, Anders has proposed something for that purpose, and perhaps he has developed some software for that purpose. There are some fundamental issues with this stuff, such as, how does the user know what he's being asked to sign? How does he know that he's not being asked to sign a document conveying the deeds for all his real property to the web site owner? In some countries where digital signatures have the full force of law, just like a real signature, this could be a serious issue. I'm personally wary of efforts that push to make it possible for users to make such legally effective signatures without solving the problems of how to protect the user. _______________________________________________ dev-tech-crypto mailing list [email protected] https://lists.mozilla.org/listinfo/dev-tech-crypto _______________________________________________ dev-tech-crypto mailing list [email protected] https://lists.mozilla.org/listinfo/dev-tech-crypto
