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Disabling the RFID in the New U.S. Passports
slashchuck writes "Along with the usual Jargonwatch and Wired/Tired articles, the January issue of Wired offers a drastic method for taking care of that RFID chip in your passport. They say it's legal ... if a bit blunt. From the article: 'The best approach? Hammer time. Hitting the chip with a blunt, hard object should disable it. A nonworking RFID doesn't invalidate the passport, so you can still use it.' "
What technology would you suggest to use to do this broadcasting? The contactless smart card chip in the passport won't do the job very effectively because:
Perhaps you could photocopy the information page and post flyers? Or just walk around holding your passport open so that any would-be passport cloner can see the MRZ data? If you *really* want to use the passport's contactless chip to distribute the data, I guess you could print your name, birthdate and passport number on a sign, hang it around your neck, and then stick your passport to it so it's held open. Given the name, birthdate and passport number, an attacker will be able to guess the MRZ fairly quickly. If you want to make them work for it a little, you could leave out the birthdate and passport number and let them guess those values. Be sure to give them your name, though, otherwise it'll take too long, because the chip just doesn't report the failed authentication attempts fast enough. There's also the small issue of the communication range of the contactless chip, but perhaps there's an area of the airport that is nicely EM-shielded so that the attacker's lab-grade transciever and signal processing equipment can talk to your passport at a reasonable range. Or perhaps you could just let the attacker give you a booster device that you could hold near your passport.
All in all, it seems like a rather ineffective way to broadcast your data. I'd go with the flyers.
Removing toungue from cheek, it's a pretty ineffective way for an attacker to try to get your data, too. There are many other approaches that are much, much easier.
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From the US State Department FAQ on electronic passports
What will happen if my Electronic passport fails at a port-of-entry?
The chip in the passport is just one of the many security features of the new passport. If the chip fails, the passport remains a valid travel document until its expiration date. The bearer will continue to processed by the port-of-entry officer as if he/she had a passport without a chip.
So unless they are going to recall all non-chipped passports, they'll have to wait quite a while to make it a requirement.
Also: Alteration or mutilation of passport: This passport must not be altered or mutilated in any way. Alteration may make it INVALID, and, if willful, may subject you to prosecution. (Title 18, U.S. Code, Section 1543)
I like your Macs, but I don't like your Mac users. (with apologies to Gandhi)
the shielding in the passport cover hold the chip incommunicado unless the passport is open
That's true if your definition of "open" is anything not held tightly closed.
It has already been demonstrated that the faraday cage effect of the shielding is negated if the passport is only open a centimeter or so, as could easily happen with a passport carried in a handbag, or pretty much anywhere there is not much pressure to hold it closed.
So, while you may not be able to crack the data from the RFID, you can certainly talk to it under conditions that are reasonably common in the field.
it requires execution of a cryptographic authentication protocol using an AES key derived from data printed inside the passport cover (called the MRZ)before it will divulge anything; and
Doesn't this strike anyone as ironic? The RFID is of no value for official use without first having to read something printed on the inside. So much for any improvement in convenience or ease of use over the previous implementation. Seems like an RFID manufacturer (patent holder?) hired a really good lobbyist.
When information is power, privacy is freedom.
Not only can the old-generation passive RFID tags be read more than "a few inches away" (to claim 1 meter="a few inches" you'd have to count the way the Congressional Budget Office does)*, but it's been more than a year since passive RFID tags which can be read anywhere from 4-8 meters away have been on the market.
... http://www.idesco.fi/library/documents/PassiveRFID -Ifsecseminar2005.pdf/
Here's a nice little marketing presentation to get you started on the capabilities of passive RFID using Ultra-High Frequency
*Yes, I know its only "1 meter" under near-ideal conditions but average street conditions still don't degrade the range to "a few inches".
I do this stuff (among other things) for a living. ...
Passive tags (like the one in the passport) can only be read a few inches away and someone with even a basic knowledge of physics knows that the power requirement to maintain an adequate magnetic field increases exponentially with distance.
While you may "do" it for a living, it sounds like you don't hack it for a living. It takes a whole different mindset to look for vulnerabilities to exploit.
Even the State Department admits the RFIDs used in the passports can be read from at least 10 feet away. NIST says they've been able to do 30 feet and are working on clever ways to get beyond even that. These numbers are for ISO 14443 RFIDs which seem to be the type used in US passports.
one has to remember that tags operating on the same frequency will tend to interfere with each other, reducing the chance of getting a good read.
There are plenty of situations in which just knowing that the RFID and associated passport are present are trouble enough. The classic example being the bomb with an "american detector" - left out in a public area it only needs to get enough of a signal fingerprint to differentiate american passports from others in order to make that passport's owner very unhappy. Put one of those into the doorframe of a mcdonalds somewhere and you don't even need to worry about long-range fancy-smancy stuff.
When information is power, privacy is freedom.
Not if they're set up to read the data when you're at the passport-scanning station.
Here's how it would work:
1) The customs official asks you for your passport.
2) You pull it out of your tinfoil sleeve and hand it over.
3) Customs official opens the front cover and scans the front page so his computer has all of the information for the security key. (It's not used for encryption. It's just a plaintext password.)
4) Customs official's station broadcasts the security key.
5) The RFID tag in your passport broadcasts your passport data.
If I have a sensitive enough high gain antenna pointed at that customs station, I now have both your security key AND all of the information in your passport.
The broadcasts in steps 4 and 5 are OMNI-DIRECTIONAL. They're relatively low-power, because according to the design, the passport's supposed to be only a few cm away from the reader.. But that's why you need a high-gain antenna.
Perhaps I'm simply naive here but if the RFID tag requires information printed inside the passport be entered into a computer then why have RFID at all?
It's an anti-forgery mechanism. A forger doesn't want to duplicate a passport, a forger wants to create a passport with the bogus holder's photo, plus some either real or real-looking but innocuous identification data. The thing the RFID's copy of the data has that the printed page doesn't have is digital signatures. A forger may be able to print a perfect-looking passport, and embed a chip loaded with all of the corresponding data, but he won't have access to the private keys necessary to apply the proper digital signature to the data. This makes the new passports essentially impossible to forge, assuming RSA remains unbroken and assuming the private key is well-protected.
There's no need to use a contactless method unless someone is picturing a scenario where customs will be something that you just walk through with your passport in your pocket or just have it tapped on a reader.
Not true. The engineers who created the passport chip specification for ICAO wanted to use off-the-shelf technology, rather than inventing and debugging something entirely new. Given how much trouble the various vendors have had making the off-the-shelf technology interoperate correctly, this was a wise choice. But off-the-shelf contact smart card technology has some fundamental limitations for this application.
First, where on a passport do you put the chip and how do you insert it? Obviously, you can't use off-the-shelf smart card readers, because the passport is the wrong shape and size. Further, passports aren't rigid enough to guarantee that the contacts will correctly land on the regions of the smart card contact plate. Using a contact chip would have required adding some card-shaped rigid plastic "page" to the passport, which would have complicated manufacturing, made the passports more fragile and probably also increased the time required for Immigration officials to insert the card.
Second, and more importantly, contact smart cards are too slow. Due to a quirk of history, contact smart cards are limited to a maximum data rate of 115kbps. Because of the inefficiency built into the ISO 7816 T=0 and T=1 protocols, that means you get about 8KiBps (note: kbps = 10^3 bits per second, KiBps = 2^10 bytes per second) throughput, *max*. And, in practice, you only get that speed by carefully matching and testing cards and readers. In the smart card world, we expect real-world transfer rates of 1-2KiBps. The ICAO data set sizes are in the range of 30-40KiB. Contactless cards, however, are either 400kbps or 800kbps. Even at the slower speed, that produces a transfer rate of over 30KiBps. You can see that a contact card's best case is around four seconds to move the data set, and a more realistic common case is 10-15 seconds. A contactless card's worst case is about 1.3s, and the best case is about 300ms.
Add to that the fact that contactless is more forgiving of passport placement accuracy than contact, and you have a really significant difference in per-person processing time. Five seconds per traveler, per agent adds up to another full-time position or two at each major airport.
All of this could have been addressed by designing a new contact interface and protocol, of course. The custom contact plate could have been much larger so the individual contact areas were much bigger, solving most of the issues. But they wanted off-the-shelf, both in the interest of development time and in the interest of cost. By using standard parts, the passport issuers and immigration agencies benefit from economies of scale that they wouldn't get with custom components.
Finally, there was really no reason *not* to go contactless. Privacy wasn't traditionally part of the security issues that passport agencies were concerned about and, in any case, the MRZ-based encryption seemed to addr
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