The Burglar Who Knew Lisp

Dr. Dobb's Journal September, 2004

"You're dressed for success, Bernie," I told myself, first because my name is Bernie and second because I was, in fact, outfitted with everything the successful 21st century B&E artist needs for a night's work. B&E: That's breaking and entering, a hobby of mine. How does the successful B&E artist outfit him- (or her-; don't want to be sexist) self these days? De rigueur is plastic film gloves, flushable in an emergency, and a penlight flashlight of the sort that anyone might carry. I add a perfectly ordinary Palm handheld with a not-so ordinary program, four inches of two-strand insulated copper wire under the leather label on the beltline of my jeans, and something that looks like a credit card if you overlook the electrical contacts on the edge.

In jeans, T-shirt, and hightops, I could pass for a jogger, say, or a programmer. From where I dropped off the car three blocks away, I was that jogger, taking advantage of the cool night air. Standing in front of the door at Blindside Enterprises, fitting my card in the slot, I was the programmer arriving for his 2am stint, obsessively tapping away at his Palm even as he unlocked the door.

The door clicked open and I slipped inside, returning card, wire, and Palm to their respective homes. I had officially entered the magic kingdom of Felonyland.

I wasn't sure how much time I had, so I didn't bother with corporate data as I shuffled through the CEO's desk and hard disk files. For personal data, e-mail and browser history are obvious places to check, as well as cookies from sites your target has visited. I had my hand in the cookie jar, so to speak, when things got all too personal.

"Hey! What are you doing in here?"

I forced my heart back down out of my nasal cavity and sized him up. In his sweatshirt, floppy hippie pants, and sandals with socks, I suspected that he was not the CEO, nor was he likely to be security. Still, he was brandishing a cell phone in an ominous way.

"I'm a burglar," I said. "I'm going through the boss's files to get some dirt on him."

He blinked twice and didn't press any buttons on the phone. Good so far.

"Don't you want to know how I got past the security system?" I didn't wait for an answer. "If you call it a security system. I've hacked way better card systems than this outfit's, let me tell you."

His pupils contracted. I had engaged his professional attention.

"Before you turn me in, maybe you'd like to know how I hacked it? You know that the security guard and the cops aren't going to be able to understand what I'm saying."

"Yeah. You better tell me all about it." He pointed at me sternly with his phone hand and sat down on the arm of a chair.

I showed him the card, the wire, and the Palm, and how they worked. He slid into the chair and started to launch the key program, but I stopped him.

"You're a hacker, I can see that," I said, and saw the look of pride he tried to conceal. "You know what I mean if I say this is Mission Impossible code?"

"You mean self destructing?"

"Affirmative." I thought that sounded Mission Impossiblish.

"So there's a password, right?"

I gave it to him.

It took him a few seconds to tire of trying out the program and then he was into the source code.

Source code. On a Palm.

"This is Lisp," he said incredulously. "You're running a Lisp interpreter on this thing."

"No other language could do what I want on this platform." I set the hook and prepared to tug it. "You know Paul Graham and Robert Morris wrote the first e-commerce toolkit in Lisp."

I could see the jolt as he took the hook. "Robert Morris? The legendary hacker?"

It took another 10 minutes to get safely out the back door, but I was really home free when he said that. Home free—but without any revealing facts about the guy who had bought Foo Bar. What was I going to tell Swaine?

Continued next month.