When I got home, I read that a group of parents was suing the school board over the surveillance cameras in the classrooms, but that they’d already lost their bid to get a preliminary injunction against them.
I don’t know who came up with the name Xnet, but it stuck. You’d hear people talking about it on the Muni. Van called me up to ask me if I’d heard of it and I nearly choked once I figured out what she was talking about: the discs I’d started distributing last week had been sneakernetted and copied all the way to Oakland in the space of two weeks. It made me look over my shoulder—like I’d broken a rule and now the DHS would come and take me away forever.
They’d been hard weeks. The BART had completely abandoned cash fares now, switching them for arphid “contactless” cards that you waved at the turnstiles to go through. They were cool and convenient, but every time I used one, I thought about how I was being tracked. Someone on Xnet posted a link to an Electronic Frontier Foundation white paper on the ways that these things could be used to track people, and the paper had tiny stories about little groups of people that had protested at the BART stations.
I used the Xnet for almost everything now. I’d set up a fake email address through the Pirate Party, a Swedish political party that hated Internet surveillance and promised to keep their mail accounts a secret from everyone, even the cops. I accessed it strictly via Xnet, hopping from one neighbor’s Internet connection to the next, staying anonymous—I hoped—all the way to Sweden. I wasn’t using w1n5t0n anymore. If Benson could figure it out, anyone could. My new handle, come up with on the spur of the moment, was M1k3y, and I got a lot of email from people who heard in chat rooms and message boards that I could help them troubleshoot their Xnet configurations and connections.
I missed Harajuku Fun Madness. The company had suspended the game indefinitely. They said that for “security reasons” they didn’t think it would be a good idea to hide things and then send people off to find them. What if someone thought it was a bomb? What if someone put a bomb in the same spot?
What if I got hit by lightning while walking with an umbrella? Ban umbrellas! Fight the menace of lightning!
I kept on using my laptop, though I got a skin-crawly feeling when I used it. Whoever had wiretapped it would wonder why I didn’t use it. I figured I’d just do some random surfing with it every day, a little less each day, so that anyone watching would see me slowly changing my habits, not doing a sudden reversal. Mostly I read those creepy obits—all those thousands of my friends and neighbors dead at the bottom of the Bay.
Truth be told, I was doing less and less homework every day. I had business elsewhere. I burned new stacks of ParanoidXbox every day, fifty or sixty, and took them around the city to people I’d heard were willing to burn sixty of their own and hand them out to their friends.
I wasn’t too worried about getting caught doing this, because I had good crypto on my side. Crypto is cryptography, or “secret writing,” and it’s been around since Roman times (literally: Augustus Caesar was a big fan and liked to invent his own codes, some of which we use today for scrambling joke punch lines in email).
Crypto is math. Hard math. I’m not going to try to explain it in detail because I don’t have the math to really get my head around it, either—look it up on Wikipedia if you really want.
But here’s the Cliff’s Notes version: Some kinds of mathematical functions are really easy to do in one direction and really hard to do in the other direction. It’s easy to multiply two big prime numbers together and make a giant number. It’s really, really hard to take any given giant number and figure out which primes multiply together to give you that number.
That means that if you can come up with a way of scrambling something based on multiplying large primes, unscrambling it without knowing those primes will be hard. Wicked hard. Like, a trillion years of all the computers ever invented working 24/7 won’t be able to do it.
There are four parts to any crypto message: the original message, called the “cleartext.” The scrambled message, called the “ciphertext.” The scrambling system, called the “cipher.” And finally there’s the key: secret stuff you feed into the cipher along with the cleartext to make ciphertext.
It used to be that crypto people tried to keep all of this a secret. Every agency and government had its own ciphers and its own keys. The Nazis and the Allies didn’t want the other guys to know how they scrambled their messages, let alone the keys that they could use to descramble them. That sounds like a good idea, right?
Wrong.
The first time anyone told me about all this prime factoring stuff, I immediately said, “No way, that’s BS. I mean, sure it’s hard to do this prime factorization stuff, whatever you say it is. But it used to be impossible to fly or go to the moon or get a hard drive with more than a few kilobytes of storage. Someone must have invented a way of descrambling the messages.” I had visions of a hollow mountain full of National Security Agency mathematicians reading every email in the world and snickering.
In fact, that’s pretty much what happened during World War II. That’s the reason that life isn’t more like Castle Wolfenstein, where I’ve spent many days hunting Nazis.
The thing is, ciphers are hard to keep secret. There’s a lot of math that goes into one, and if they’re widely used, then everyone who uses them has to keep them a secret, too, and if someone changes sides, you have to find a new cipher.
The Nazi cipher was called Enigma, and they used a little mechanical computer called an Enigma Machine to scramble and unscramble the messages they got. Every sub and boat and station needed one of these, so it was inevitable that eventually the Allies would get their hands on one.
When they did, they cracked it. That work was led by my personal all-time hero, a guy named Alan Turing, who pretty much invented computers as we know them today. Unfortunately for him, he was gay, so after the war ended, the stupid British government forced him to get shot up with hormones to “cure” his homosexuality and he killed himself. Darryl gave me a biography of Turing for my fourteenth birthday—wrapped in twenty layers of paper and in a recycled Batmobile toy, he was like that with presents—and I’ve been a Turing junkie ever since.
Now the Allies had the Enigma Machine, and they could intercept lots of Nazi radio messages, which shouldn’t have been that big a deal, since every captain had his own secret key. Since the Allies didn’t have the keys, having the machine shouldn’t have helped.
Here’s where secrecy hurts crypto. The Enigma cipher was flawed. Once Turing looked hard at it, he figured out that the Nazi cryptographers had made a mathematical mistake. By getting his hands on an Enigma Machine, Turing could figure out how to crack any Nazi message, no matter what key it used.
That cost the Nazis the war. I mean, don’t get me wrong. That’s good news. Take it from a Castle Wolfenstein veteran. You wouldn’t want the Nazis running the country.
After the war, cryptographers spent a lot of time thinking about this. The problem had been that Turing was smarter than the guy who thought up Enigma. Any time you had a cipher, you were vulnerable to someone smarter than you coming up with a way of breaking it.
And the more they thought about it, the more they realized that anyone can come up with a security system that he can’t figure out how to break. But no one can figure out what a smarter person might do.
You have to publish a cipher to know that it works. You have to tell as many people as possible how it works, so that they can thwack on it with everything they have, testing its security. The longer you go without anyone finding a flaw, the more secure you are.
Which is how it stands today. If you want to be safe, you don’t use crypto that some genius thought of last week. You use the stuff that people have been using for as long as possible without anyone figuring out how to break them. Whether you’re a bank, a terrorist, a government or a teenager, you use the same ciphers.
If you tried to use your own cipher, there’d be the chance that someone out there had
found a flaw you missed and was doing a Turing on your butt, deciphering all your “secret” messages and chuckling at your dumb gossip, financial transactions and military secrets.
So I knew that crypto would keep me safe from eavesdroppers, but I wasn’t ready to deal with histograms.
I got off the BART and waved my card over the turnstile as I headed up to the 24th Street station. As usual, there were lots of weirdos hanging out in the station, drunks and Jesus freaks and intense Mexican men staring at the ground and a few gang kids. I looked straight past them as I hit the stairs and jogged up to the surface. My bag was empty now, no longer bulging with the ParanoidXbox discs I’d been distributing, and it made my shoulders feel light and put a spring in my step as I came up the street. The preachers were at work still, exhorting in Spanish and English about Jesus and so on.
The counterfeit sunglass sellers were gone, but they’d been replaced by guys selling robot dogs that barked the national anthem and would lift their legs if you showed them a picture of Osama bin Laden. There was probably some cool stuff going on in their little brains and I made a mental note to pick a couple of them up and take them apart later. Face-recognition was pretty new in toys, having only recently made the leap from the military to casinos trying to find cheats to law enforcement.
I started down 24th Street toward Potrero Hill and home, rolling my shoulders and smelling the burrito smells wafting out of the restaurants and thinking about dinner.
I don’t know why I happened to glance back over my shoulder, but I did. Maybe it was a little bit of subconscious sixth sense stuff. I knew I was being followed.
They were two beefy white guys with little mustaches that made me think of either cops or the gay bikers who rode up and down the Castro, but gay guys usually had better haircuts. They had on windbreakers the color of old cement and blue jeans, with their waistbands concealed. I thought of all the things a cop might wear on his waistband, of the utility belt that DHS guy in the truck had worn. Both guys were wearing Bluetooth headsets.
I kept walking, my heart thumping in my chest. I’d been expecting this since I started. I’d been expecting the DHS to figure out what I was doing. I took every precaution, but severe haircut lady had told me that she’d be watching me. She’d told me I was a marked man. I realized that I’d been waiting to get picked up and taken back to jail. Why not? Why should Darryl be in jail and not me? What did I have going for me? I hadn’t even had the guts to tell my parents—or his—what had really happened to us.
I quickened my step and took a mental inventory. I didn’t have anything incriminating in my bag. Not too incriminating, anyway. My SchoolBook was running the crack that let me IM and stuff, but half the people in school had that. I’d changed the way I encrypted the stuff on my phone—now I did have a fake partition that I could turn back into cleartext with one password, but all the good stuff was hidden, and needed another password to open up. That hidden section looked just like random junk—when you encrypt data, it becomes indistinguishable from random noise—and they’d never even know it was there.
There were no discs in my bag. My laptop was free of incriminating evidence. Of course, if they thought to look hard at my Xbox, it was game over. So to speak.
I stopped where I was standing. I’d done as good a job as I could of covering myself. It was time to face my fate. I stepped into the nearest burrito joint and ordered one with carnitas—shredded pork—and extra salsa. Might as well go down with a full stomach. I got a bucket of horchata, too, an ice-cold rice drink that’s like watery, semisweet rice pudding (better than it sounds).
I sat down to eat, and a profound calm fell over me. I was about to go to jail for my “crimes,” or I wasn’t. My freedom since they’d taken me in had been just a temporary holiday. My country was not my friend anymore: we were now on different sides and I’d known I could never win.
The two guys came into the restaurant as I was finishing the burrito and going up to order some churros—deep-fried dough with cinnamon sugar—for dessert. I guess they’d been waiting outside and got tired of my dawdling.
They stood behind me at the counter, boxing me in. I took my churro from the pretty granny and paid her, taking a couple of quick bites of the dough before I turned around. I wanted to eat at least a little of my dessert. It might be the last dessert I got for a long, long time.
Then I turned around. They were both so close I could see the zit on the cheek of the one on the left, the little booger up the nose of the other.
“’Scuse me,” I said, trying to push past them. The one with the booger moved to block me.
“Sir,” he said, “can you step over here with us?” He gestured toward the restaurant’s door.
“Sorry, I’m eating,” I said and moved again. This time he put his hand on my chest. He was breathing fast through his nose, making the booger wiggle. I think I was breathing hard, too, but it was hard to tell over the hammering of my heart.
The other one flipped down a flap on the front of his wind-breaker to reveal a SFPD insignia. “Police,” he said. “Please come with us.”
“Let me just get my stuff,” I said.
“We’ll take care of that,” he said. The booger one stepped right up close to me, his foot on the inside of mine. You do that in some martial arts, too. It lets you feel if the other guy is shifting his weight, getting ready to move.
I wasn’t going to run, though. I knew I couldn’t outrun fate.
Chapter 7
They took me outside and around the corner to a waiting unmarked police car. It wasn’t like anyone in that neighborhood would have had a hard time figuring out that it was a cop car, though. Only police drove big Crown Victorias now that gas had hit seven bucks a gallon. What’s more, only cops could double-park in the middle of Van Ness Street without getting towed by the schools of predatory tow operators that circled endlessly, ready to enforce San Francisco’s incomprehensible parking regulations and collect a bounty for kidnapping your car.
Booger blew his nose. I was sitting in the back seat, and so was he. His partner was sitting in the front, typing with one finger on an ancient, ruggedized laptop that looked like Fred Flint-stone had been its original owner.
Booger looked closely at my ID again. “We just want to ask you a few routine questions.”
“Can I see your badges?” I said. These guys were clearly cops, but it couldn’t hurt to let them know I knew my rights.
Booger flashed his badge at me too fast for me to get a good look at it, but Zit in the front seat gave me a long look at his. I got their division number and memorized the four-digit badge number. It was easy: 1337 is also the way hackers write “leet,” or “elite.”
They were both being very polite and neither of them was trying to intimidate me the way that the DHS had done when I was in their custody.
“Am I under arrest?”
“You’ve been momentarily detained so that we can ensure your safety and the general public safety,” Booger said.
He passed my driver’s license to Zit, who pecked it slowly into his computer. I saw him make a typo and almost corrected him, but figured it was better to just keep my mouth shut.
“Is there anything you want to tell me, Marcus? Do they call you Marc?”
“Marcus is fine,” I said. Booger looked like he might be a nice guy. Except for the part about kidnapping me into his car, of course.
“Marcus. Anything you want to tell me?”
“Like what? Am I under arrest?”
“You’re not under arrest right now,” Booger said. “Would you like to be?”
“No,” I said.
“Good. We’ve been watching you since you left the BART. Your Fast Pass says that you’ve been riding to a lot of strange places at a lot of funny hours.”
I felt something let go inside my chest. This wasn’t about the Xnet at all, then, not really. They’d been watching my subway use and wanted to know why it had been so freaky lately. How totally stupid.
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“So you guys follow everyone who comes out of the BART station with a funny ride history? You must be busy.”
“Not everyone, Marcus. We get an alert when anyone with an uncommon ride profile comes out and that helps us assess whether we want to investigate. In your case, we came along because we wanted to know why a smart-looking kid like you had such a funny ride profile.”
Now that I knew I wasn’t about to go to jail, I was getting pissed. These guys had no business spying on me—Christ, the BART had no business helping them to spy on me. Where the hell did my subway pass get off on finking me out for having a “nonstandard ride pattern”?
“I think I’d like to be arrested now,” I said.
Booger sat back and raised his eyebrow at me.
“Really? On what charge?”
“Oh, you mean riding public transit in a nonstandard way isn’t a crime?”
Zit closed his eyes and scrubbed them with his thumbs.
Booger sighed a put-upon sigh. “Look, Marcus, we’re on your side here. We use this system to catch bad guys. To catch terrorists and drug dealers. Maybe you’re a drug dealer yourself. Pretty good way to get around the city, a Fast Pass. Anonymous.”
“What’s wrong with anonymous? It was good enough for Thomas Jefferson. And by the way, am I under arrest?”
“Let’s take him home,” Zit said. “We can talk to his parents.”
“I think that’s a great idea,” I said. “I’m sure my parents will be anxious to hear how their tax dollars are being spent—”
I’d pushed it too far. Booger had been reaching for the door handle but now he whirled on me, all Hulked out and throbbing veins. “Why don’t you shut up right now, while it’s still an option? After everything that’s happened in the past two weeks, it wouldn’t kill you to cooperate with us. You know what, maybe we should arrest you. You can spend a day or two in jail while your lawyer looks for you. A lot can happen in that time. A lot. How’d you like that?”