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Tech Policy Challenges for the Obama Administration

January 20, 2009 by

[Princeton’s Woodrow Wilson School asked me to write a short essay on information technology challenges facing the Obama Administration, as part of the School’s Inaugural activities. Here is my essay.]

Digital technologies can make government more effective, open and transparent, and can make the economy as a whole more flexible and efficient. They can also endanger privacy, disrupt markets, and open the door to cyberterrorism and cyberespionage. In this crowded field of risks and opportunities, it makes sense for the Obama administration to focus on four main challenges.

The first challenge is cybersecurity. Government must safeguard its own mission critical systems, and it must protect privately owned critical infrastructures such as the power grid and communications network. But it won’t be enough to focus only on a few high priority, centralized systems. Much of digital technology’s value—and, today, many of the threats—come from ordinary home and office systems. Government can use its purchasing power to nudge the private sector toward products that are more secure and reliable; it can convene standards discussions; and it can educate the public about basic cybersecurity practices.

The second challenge is transparency. We can harness the potential of digital technology to make government more open, leading toward a better informed and more participatory civic life. Some parts of government are already making exciting progress, and need high-level support; others need to be pushed in the right direction. One key is to ensure that data is published in ways that foster reuse, to support an active marketplace of ideas in which companies, nonprofits, and individuals can find the best ways to analyze, visualize, and “mash up” government information.

The third challenge is to maintain and increase America’s global lead in information technology, which is vital to our prosperity and our role in the world. While recommitting to our traditional strengths, we must work to broaden the reach of technology. We must bring broadband Internet connections to more Americans, by encouraging private-sector investment in high-speed network infrastructure. We must provide better education in information technology, no less than in science or math, to all students. Government cannot solve these problems alone, but can be a catalyst for progress.

The final challenge is to close the culture gap between politicians and technology leaders. The time for humorous anecdotes about politicians who “don’t get” technology, or engineers who are blind to the subtleties of Washington, is over. Working together, we can translate technological progress into smarter government and a more vibrant, dynamic private sector.

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Debugging the Zune Blackout

January 12, 2009 by

On December 31, some models of the Zune, Microsoft’s portable music player, went dark. The devices were unusable until the following day. Failures like this are sometimes caused by complex chains of mishaps, but this particular one is due to a single programming error that is reasonably easy to understand. Let’s take a look.

Here is the offending code (reformatted slightly), in the part of the Zune’s software that handles dates and times:

year = 1980;

while (days > 365) {
    if (IsLeapYear(year))  {
        if (days > 366)  {
            days -= 366;
            year += 1;
        }
     } else {
        days -= 365;
        year += 1;
    }
}

At the beginning of this code, the variable days is the number of days that have elapsed since January 1, 1980. Given this information, the code is supposed to figure out (a) what year it is, and (b) how many days have elapsed since January 1 of the current year. (Footnote for pedants: here “elapsed since” actually means “elapsed including”, so that days=1 on January 1, 1980.)

On December 31, 2008, days was equal to 10592. That is, 10592 days had passed since January 1, 1980. It follows that 10226 days had passed since January 1, 1981. (Why? Because there were 366 days in 1980, and 10592 minus 366 is 10226.) Applying the same logic repeatedly, we can figure out how many days had passed since January 1 of each subsequent year. We can stop doing this when the number of remaining days is less than a year — then we’ll know which year it is, and which day within that year.

This is the method used by the Zune code quoted above. The code keeps two variables, days and year, and it maintains the rule that days days have passed since January 1 of year. The procedure continues as long as there are more than 365 days remaining (“while (days > 365)“). If the current year is a leap year (“if (IsLeapYear(year))“), it subtracts 366 from days and adds one to year; otherwise it subtracts 365 from days and adds one to year.

On December 31, 2008, starting with days=10592 and years=1980, the code would eventually reach the point where days=366 and year=2008, which means (correctly) that 366 days had elapsed since January 1, 2008. To put it another way, it was the 366th day of 2008.

This is where things went horribly wrong. The code decided it wasn’t time to stop yet, because days was more than 365. (“while (days > 365)”) It then asked whether year was a leap year, concluding correctly that 2008 was a leap year. (“if (IsLeapYear(year))”) It next determined that days was not greater than 366 (“if (days > 366)“), so that no arithmetic should be performed. The code had gotten stuck: it couldn’t stop, because days was greater than 365, but it couldn’t make progress, because days was not greater than 366. This section of code would keep running forever — leaving the Zune seemingly dead in the water.

The only way out of this mess was to wait until the next day, when the computation would go differently. Fortunately, the same problem would not occur again until December 31, 2012 (the last day of the next leap year), and Microsoft has ample time to patch the Zune code by then.

What lessons can we learn from this? First, even seemingly simple computations can be hard to get right. Microsoft’s quality control process, which is pretty good by industry standards, failed to catch the problem in this simple code. How many more errors like this are lurking in popular software products? Second, errors in seemingly harmless parts of a program can have serious consequences. Here, a problem computing dates caused the entire system to be unusable for a day.

This story might help to illustrate why experienced engineers assume that any large software program will contain errors, and why they distrust anyone who claims otherwise. Getting a big program to run at all is an impressive feat of engineering. Making it error-free is too much to hope for. For the foreseeable future, software errors will be a fact of life.

[Hat tip: “itsnotabigtruck” at ZuneBoards.]

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Predictions for 2009

January 7, 2009 by

Here are our predictions for 2009. These are based on input from Andrew Appel, Joe Calandrino, Will Clarkson, Ari Feldman, Ed Felten, Alex Halderman, Joseph Lorenzo Hall, Tim Lee, Paul Ohm, David Robinson, Dan Wallach, Harlan Yu, and Bill Zeller. Please note that individual contributors (including me) don’t necessarily agree with all of these predictions.

(1) DRM technology will still fail to prevent widespread infringement. In a related development, pigs will still fail to fly.

(2) Patent reform legislation will come closer to passage in this Congress, but will ultimately fail as policymakers wait to determine the impact of the Bilski case’s apparent narrowing of business model patentability.

(3) As lawful downloading of music and movies continues to grow, consumer satisfaction with lossy formats will decline, and higher-priced options that offer higher fidelity will begin to predominate. At least one major online music service will begin to offer music in a lossless format.

(4) The RIAA’s “graduated response” initiative will sputter and die because ISPs are unwilling to cut off users based on unrebutted accusations. Lawsuits against individual end-user infringers will quietly continue.

(5) The DOJ will bring criminal actions against big-time individual copyright infringers based on data culled from the server logs of a large “private” BitTorrent community.

(6) Questions over the enforceability of free / open source software licenses will move closer to resolution.

(7) NebuAd and the regional ISPs recently sued for deploying NebuAd’s advertising system will settle with the class action plantiffs for an undisclosed sum. At least in part because of the lawsuit and settlement, no U.S. ISP will deploy a new NebuAd/Phorm-like system in 2009. Meanwhile, Phorm will continue to be successful with privacy regulators in the UK and will sign up reluctant ISPs there who are facing competitive pressure. Activists will raise strong objections to no avail.

(8) The federal Court of Appeals for the Ninth Circuit will hear oral argument in the case of U.S. v. Lori Drew, the Megan Meier/MySpace prosecution. By year’s end, the Ninth Circuit panel still will not have issued a decision, although after oral argument, the pundits will predict a 3-0 or 2-1 reversal of the conviction.

(9) As a result of the jury’s guilty verdict in U.S. v. Lori Drew, dozens of plaintiffs will file civil lawsuits in 2009 alleging violations of the federal Computer Fraud and Abuse Act premised on the theory that one can “exceed authorized access” or act “in excess of authorization” by violating Terms of Service. Thankfully, the Department of Justice won’t bring any other criminal cases premised on this theory, at least not until it sees how the Ninth Circuit rules.

(10) The Computer Fraud and Abuse Act (CFAA) will be the new DMCA. Many will argue that the law needs to be reformed, but this argument will struggle to gain traction with the lay public, notwithstanding the fact that lay users face potential liability for routine behaviors due to CFAA overbreadth.

(11) An academic security researcher will face prosecution under the CFAA, anti wire tapping laws, or other computer intrusion statutes for violations that occurred in the process of research.

(12) An affirmative action lawsuit will be filed against a university, challenging the use of a software algorithm used in evaluating applicants.

(13) There will be lots of talk about net neutrality but no new legislation, as everyone waits to see how the Comcast/BitTorrent issue plays out in the courts.

(14) The Obama administration will bring an atmosphere of antitrust enforcement to the IT industry, but no major cases will be brought in 2009.

(15) The new administration will be seen as trying to “reboot” the FCC.

(16) One of the major American voting system manufacturers (Diebold/Premier, Sequoia, ES&S, or Hart InterCivic) will go out of business or be absorbed into one of its rivals.

(17) The federal voting machine certification regime will increasingly be seen as a failure. States will strengthen their own certification processes, and at least one major state will stop requiring federal certification. The failure of the federal process to certify systems or software patches in a timely fashion will be cited as a reason for this move.

(18) Estonia and other countries will continue experimenting in real elections with online or mobile phone voting. They will claim that these trials are successful because “nothing went wrong.” Security analysts will continue to claim that these systems are fundamentally flawed and will continue to be ignored. Exactly the same thing will continue to happen with U.S. overseas and military voters.

(19) We’ll see the first clear-cut evidence of a malicious attack on a voting system fielded in a state or local election. This attack will exploit known flaws in a “toe in the water” test and vendors will say they fixed the flaw years ago and the new version is in the certification pipeline.

(20) U.S. federal government computers will suffer from at least one high-profile compromise by a foreign entity, leaking a substantial amount of classified or highly sensitive information abroad.

(21) There will be one or more major Internet outages attributed to attacks on DNS, BGP, or other Internet plumbing that is immediately labeled an act of “cyber-warfare” or “cyber-terrorism.” The actual cause will be found to be the action of spammers or other professional Internet miscreants.

(22) Present flaws in the web’s Certification Authority process, such as the MD5 issue or the leniency of some CAs in issuing certificates, will lead to regulation of the CA process. Among other things, there will be calls for restrictions on which CAs can issue certs for which Top Level Domains.

(23) One or more major Internet services or top-tier network providers will experience prolonged failures and/or unrecoverable data severe enough that the company’s president ends up testifying before Congress about it.

(24) Shortly after the start of the new administration, the TSA will quietly phase out the ban on flying with liquids or stop enforcing it in practice. The color-coded national caution levels (which have remained at “orange” forever) will be phased out.

(25) All 20 of the top 20 U.S. newspapers by circulation will experience net reductions in their newsroom headcounts in 2009. At least 15 of the 20 will see weekday circulation decline by 15% or more over the course of the year. By the end of the year, at least one major U.S. city will lack a daily newspaper.

(26) Advertising spending in older media will plummet, but online ad spending will be roughly level, as advertisers warm to online ads whose performance is more easily measured. Traditional media will be forced to offer advertisers fire sale prices, and the ratio of content to advertising in many traditional media outlets will increase.

(27) An embarrassing leak of personal data will emerge from one or more of the social networking firms (e.g., Facebook), leading Congress to consider legislation that probably won’t solve the problem and will never actually reach the floor for a vote.

(28) Facebook will be sold for $4 billion and Mark Zuckerberg will step down as CEO.

(29) Web 2.0 startups will not be hammered by the economic downtown. In fact, web 2.0 innovation may prove to be countercyclical. Costs are controllable: today’s workstyles don’t require lavish office space, marketing can be viral, and pay-as-you-go computing services eliminate the need for big upfront investments in infrastructure. Laid off big-company workers and refugees from the financial world will keep skilled wages low. The surge in innovation will be real, but its effects will mostly be felt in future years.

(30) The Blu-ray format will increasingly be seen as a failure as customers rely more on online streaming.

(31) Emboldened by Viacom’s example against Time Warner, TV network owners will increasingly demand higher payments from cable companies with the threat of moving content online instead. Cable companies will attempt to more heavily limit the content that network owners can host on Hulu and other sites.

(32) The present proliferation of incompatible set-top boxes that aim to connect your TV to the Internet will lead to the establishment of a huge industry consortium with players from three major interest groups (box builders, content providers, software providers), reminiscent of the now-defunct SDMI consortium, and with many of the same members. In 2009, they will generate a variety of press releases but will accomplish nothing.

(33) A hot Christmas item will be a cheap set-top box that allows normal people to download, organize, and view video and audio podcasts in their own living rooms. This product will work with all of the major free online sources of audio and video, and a few of the paid sources.

(34) Internet Explorer’s usage share will fall below 50 percent for the first time in a decade, spurred by continued growth of Firefox and Safari and deals with OEMs to pre-load Google Chrome.

(35) Somebody besides Apple will sell an iPod clone that’s a drop-in replacement for a real iPod, complete with support for iTunes DRM, video playback, and so forth. Apple will sue (or threaten to sue), but won’t be able to stop distribution of this product.

(36) Apple will release a netbook, which will be a souped-up iPhone with an 8″ screen and folding keyboard. It will sell for $899.

(37) No white space devices will be approved for use by the FCC. Submitted spectrum sensing devices will fare well in both laboratory and field tests, but approval will be delayed politically by the anti-white space lobby.

(38) More and more Internet traffic will encrypted, as concern grows about eavesdropping, content modification, filtering, and security attacks.

Feel free to offer your own predictions in the comments.

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2008 Predictions Scorecard

January 6, 2009 by

As usual, we’ll kick off the new year by reviewing the predictions we made for the previous year. Here now, our 2008 predictions, in italics, with hindsight in ordinary type.

(1) DRM technology will still fail to prevent widespread infringement. In a related development, pigs will still fail to fly.

We predict this every year, and it’s always right. This prediction is so obvious that it’s almost unfair to count it. Verdict: right.

(2) Copyright issues will still be gridlocked in Congress.

We could predict this every year, and it would almost always be right. History teaches that it usually takes a long time to build consensus for any copyright changes. Verdict: right.

(3) No patent reform bill will be passed. Baby steps toward a deal between the infotech and biotech industries won’t lead anywhere.

Verdict: right.

(4) DRM-free sales will become standard in the music business. The movie studios will flirt with the idea of DRM-free sales but won’t take the plunge, yet.

This was basically right. DRM-free music sales are much more common than before. Whether they’re “standard” is a matter for debate. The movie studios haven’t followed the record industry, yet. Verdict: mostly right.

(5) The 2008 elections will not see an e-voting meltdown of Florida 2000 proportions, but a bevy of smaller problems will be reported, further fueling the trend toward reform.

As predicted, there was no meltdown but we did see a bevy of smaller problems. Whether this fueled the trend toward reform is debatable. The problems that did occur tended to be ignored because the presidential election wasn’t close. Verdict: mostly right.

(6) E-voting lawsuits will abound, with voters suing officials, officials suing other officials, and officials suing vendors (or vice versa).

There were some lawsuits, but they didn’t “abound”. Verdict: mostly wrong.

(7) Second Life will jump the shark and the cool kids will start moving elsewhere; but virtual worlds generally will lumber on.

Second Life seems to have lost its cool factor, but then so have virtual worlds generally. Still, they’re lumbering on. Verdict: mostly right.

(8) MySpace will begin its long decline, losing customers for the first time.

I haven’t seen data to confirm or refute this one. (Here’s one source.) Comscore said that Facebook passed MySpace in user share, but that doesn’t imply that MySpace decreased. Verdict: unknown.

(9) The trend toward open cellular data networks will continue, but not as quickly as optimists had hoped.

This one is hard to call. The growth of Android and iPhone unlocking would seem to be steps toward open cellular data networks, but the movement has not been rapid. Verdict: mostly right.

(10) If a Democrat wins the White House, we’ll hear talk about reinvigorated antitrust enforcement in the tech industries. (But of course it will all be talk, as the new administration won’t take office until 2009.)

Verdict: right.

(11) A Facebook application will cause a big privacy to-do.

There were Facebook privacy issues, but mostly about non-application issues. Overall, interest in Facebook apps declined during the year. Verdict: mostly wrong.

(12) There will be calls for legislation to create a sort of Web 2.0 user’s bill of rights, giving users rights to access and extract information held by sites; but no action will be taken.

Verdict: right.

(13) An epidemic of news stories about teenage webcam exhibitionism will lead to calls for regulation.

Verdict: wrong.

(14) Somebody will get Skype or a similar VoIP client running on an Apple iPhone and it will, at least initially, operate over AT&T’s cellular phone network. AT&T and/or Apple will go out of their way to break this, either by filtering the network traffic or by locking down the iPhone.

Various VoIP clients did run on the iPhone. Apple said they would allow this over conventional WiFi networks but intended to prevent it on the cellular network, presumably by banning from the iPhone App Store any application that provided VoIP on the cell network. Verdict: right.

Our final scorecard: six right, four mostly right, two mostly wrong, one wrong, one unknown.

Stay tuned for our 2009 predictions.

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Researchers Show How to Forge Site Certificates

December 30, 2008 by

Today at the Chaos Computing Congress, a group of researchers (Alex Sotirov, Marc Stevens, Jake Appelbaum, Arjen Lenstra, Benne de Weger, and David Molnar) announced that they have found a way to forge website certificates that will be accepted as valid by most browsers. This means that they can successfully impersonate any website, even for secure connections.

Let me unpack that for non-experts.

One of the cornerstones of web security is the use of secure connections. When your browser makes a secure connection to (say) Amazon and gets a page to display, the browser displays in its address bar a URL like “https://www.amazon.com”. The “https” indicates that the secure (https) protocol was used, and the browser also displays a happy blue lock or key icon to tell you the connection was secured.

The browser cooperates with Amazon’s web server to secure the connection via a two-step process. First, the two computers negotiate a shared secret key that they can use to communicate privately, using crypto tricks that I won’t describe here. Second, your browser authenticates Amazon’s web server, that is, it assures itself that the party on the other end of the connection is the genuine Amazon.com server.

Amazon has a digital certificate that it sends to your browser, as part of proving its identity. The certificate is issued by a party called a certification authority or CA. Your browser comes pre-programmed with a list of CAs its trusts; you can change the list but hardly anyone does. If your browser makes an encrypted connection to “amazon.com”, and the party on the other end of the connection owns a certificate for the name “amazon.com”, and that certificate was issued by a CA that your browser trusts, then your browser will conclude that it has a secure connection to amazon.com.

Now we can understand what the researchers accomplished: they showed how to forge a certificate corresponding to any address on the Web. For example, they can forge a certificate that allows themselves, or you, or me, or anybody, to impersonate amazon.com, or freedom-to-tinker.com, or maybe even fbi.gov. That is supposed to be impossible, for obvious reasons.

The forged certificates will say they were issued by a CA called “Equifax Secure Global eBusiness”, which is trusted by the major browsers. The forged certificates will be perfectly valid; but they will have been made by forgers, not by the Equifax CA.

To do this, the researchers exploited a cryptographic weakness in one of the digital signature methods, “MD5 with RSA”, supported by the Equifax CA. The first step in this digital signature method is to compute the hash (strictly speaking, the cryptographic hash) of the certificate contents.

The hash is a short (128-bit) code that is supposed to be a kind of unique digest of the certificate contents. To be secure, the hash method has to have several properties, one of which is that it should be infeasible to find a collision, that is, to find two values A and B which have the same hash.

It was already known how to find collisions in MD5, but the researchers improved the existing collision-finding methods, so that they can now find two values R and F that have the same hash, where R is a “real” certificate that the CA will be willing to sign, and F is a forged certificate. This is deadly, because it means that a digital signature on R will also be a valid signature on F — so the attacker can ask the CA to sign the real certificate R, then copy the resulting signature onto F — putting a valid CA signature onto a certificate that the CA would never voluntarily sign.

To demonstrate this, the researchers created a forged certificate signed by the Equifax CA. For safety, they made the forged certificate expire in the past and point to a harmless site. But it’s clear from their description that they can forge a certificate for any site they want.

Whose fault is this? Partly it’s a consequence of problems with the MD5 hash method. It’s been known for a few years that MD5 is in the process of melting down, so prudent designers have been moving away from MD5, replacing it with newer, better hash methods. Similarly, prudent CAs should not be signing certificates that use MD5-based signature methods; instead they should insist on signature methods involving stronger hashes. The Equifax CA did not follow this precaution.

The problem can be fixed, for now, by having CAs refuse to create new MD5-based signatures. But this is a sobering reminder that the certification process that underlies web site authentication — a mechanism we all rely upon daily — is far from bulletproof.

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