At 06:51 PM 11/16/96 -0800, Tim May wrote:

And sabotaging the GAK scheme in more devious ways remains an option.

I see several "leverage" points here: The cards can use either a "dongle" model, similar to that used in ordinary copy protection, which has to date been a big failure - or they can use an "on-card processor" model, where the card does the actual crypto processing. This will be tough to break using the traditional cracking techniques, but will also be expensive. And card distribution can be either weak or strict; if it's a weak model (e.g., cards are sold at Fry's or 7-11 :) or are otherwise easy to come by) it'll be tough to control their distribution and export. It's a little easier to control the export of chips than to control the export of software, but neither is easy. And strict distribution will cost an enormous amount of time and money as some agency or another is deputized or created to check credentials, keep records, issue keycards, charge fees, and so forth. If cards are easy to come by, requiring them won't be much of a deterrent to the use of strong crypto; the people the government is supposedly trying to keep from using crypto (terrorists, spies, etc) are already accustomed to keeping and purchasing things which are forbidden. If cards are difficult to come by, that's a big hole waiting for someone to fill with software crypto, or software tricks to get around the hardware requirements. One bug/feature I suspect we'll see will be the inclusion of the keycard's ID in every message that it signs, facilitating detection of unauthorized use and traffic analysis. Without this, the scheme seems entirely futile. (Which is not to say that the US Government hasn't done some futile things :), but ..) Another likely feature is an expiration date, such that the cards stop working after X months and the owner must go to the Bureau of Crypto Control and show his/her credentials and exchange the old card for a new one. Of course, if you've got outstanding warrants or haven't filed your taxes or are in arrears for child support or are a "foreign person" or have been saying illegal/controversial things with your crypto card, well, perhaps you won't feel like going down to the BCC after all. So they're going to have to find a way to make the cards easy/cheap enough to get that many people will adopt them; but they have to be expensive/difficult enough to get that people won't want to "lose" them, lest they fall into the hands of the wrong people. And that seems like a difficult task, especially if opponents of the scheme continue to provide cheap/free software-only solutions. And, as always, folks not subject to the US export regulations won't need to fuss with all of this regulatory bullshit, and can produce strong software-only crypto, or drop-in replacements for the "policy chips" which are distributed without government control. -- Greg Broiles | US crypto export control policy in a nutshell: gbroiles@netbox.com | http://www.io.com/~gbroiles | Export jobs, not crypto. |