Digital Fortress Chapter 5

Where is everyone? Susan wondered as she crossed the deserted Crypto floor. whatsoever requisite.Although intimately NSA departments were fully staffed seven days a week, Crypto was gener aloney quiet on Saturdays. Cryptographic mathematicians were by nature high-strung workaholics, and there existed an unwritten rule that they take Saturdays off except in emergencies. Code-breakers were as well valuable a commodity at the NSA to risk losing them to burnout.As Susan traversed the floor, TRANSLTR loomed to her discipline. The sound of the generators eight stories below sounded specially ominous today. Susan never liked being in Crypto during off hours. It was like being trapped but in a cage with some grand, futuristic beast. She quickly made her way toward the commanders office.Strathmores glass-walled workstation, nicknamed the fishbowl for its look when the drapes were open, stood high atop a set of catwalk stairs on the back wall of Crypto. As Susan climbed the grated step s, she gazed up at Strathmores thick, oak access. It bore the NSA seal-a bald eagle fiercely clutching an ancient skeleton identify. Behind that door sat one of the greatest men shed ever met.Commander Strathmore, the fifty-six-year-old deputy director of operations, was like a father to Susan. He was the one whod hired her, and he was the one whod made the NSA her home. When Susan joined the NSA over a decade ago, Strathmore was dealering the Crypto Development Division-a training ground for new cryptographers-new male cryptographers. Although Strathmore never tolerated the hazing of anyone, he was curiously protective of his sole female staff member. When accused of favoritism, he simply replied with the truth Susan Fletcher was one of the brightest preadolescent recruits hed ever seen, and he had no intention of losing her to sexual harassment. whizz of the cryptographers foolishly decided to test Strathmores resolve.One morning during her first year, Susan dropped by the new cryptographers lounge to get some paperwork. As she left, she noticed a picture of herself on the bulletin board. She almost fainted in embarrassment. There she was, reclining on a bed and wearing away only panties.As it turned out, one of the cryptographers had digitally s ordurened a photo from a pornographic duration and edited Susans head onto someone elses body. The effect had been quite convincing.Unfortunately for the cryptographer responsible, Commander Strathmore did not begin the stunt even remotely amusing. Two hours ulterior, a landmark memo went outEMPLOYEE CARL AUSTIN alter FOR INAPPROPRIATE CONDUCT.From that day on, nobody messed with her Susan Fletcher was Commander Strathmores golden girl.But Strathmores young cryptographers were not the only ones who learned to respect him early in his career Strathmore made his presence known to his superiors by proposing a trope of unorthodox and highly successful tidings operations. As he moved up the ranks, Trevor Strathmore became known for his cogent, reductive analyses of highly complex situations. He seemed to have an uncanny ability to see past the moral perplexities contact the NSAs difficult decisions and to act without remorse in the interest of the common good.There was no doubt in anyones mind that Strathmore loved his country. He was known to his colleagues as a patriot and a visionary a decent man in a world of lies.In the years since Susans arrival at the NSA, Strathmore had skyrocketed from head of Crypto Development to second-in-command of the entire NSA. right away only one man outranked Commander Strathmore there-Director Leland Fontaine, the mythical overlord of the bunk Palace-never seen, occasionally heard, and eternally feared. He and Strathmore seldom saw eye to eye, and when they met, it was like the clash of the titans. Fontaine was a giant star among giants, but Strathmore didnt seem to care. He argued his ideas to the director with all the restraint of an impassi oned boxer. Not even the electric chair of the United States dared challenge Fontaine the way Strathmore did. One needed political immunity to do that-or, in Strathmores case, political indifference.Susan arrived at the top of the stairs. Before she could knock, Strathmores electronic door lock buzzed. The door swung open, and the commander waved her in.Thanks for coming, Susan. I owe you one.Not at all. She smiled as she sat opposite his desk.Strathmore was a rangy, thick-fleshed man whose muted features somehow disguised his impenetrable-nosed efficiency and demand for perfection. His gray eyes usually suggested a confidence and judgement born from experience, but today they looked wild and unsettled.You look beat, Susan said.Ive been better. Strathmore sighed.Ill say, she thought.Strathmore looked as bad as Susan had ever seen him. His cutting off gray hair was disheveled, and even in the rooms crisp air-conditioning, his forehead was beaded with sweat. He looked like hed sl ept in his suit. He was sitting behind a modern desk with two recessed keypads and a computer supervise at one end. It was strewn with computer printouts and looked like some sort of alien cockpit propped there in the plaza of his curtained chamber.Tough week? she inquired.Strathmore shrugged. The usual. The pairs all over me intimately civilian privacy rights again.Susan chuckled. The EFF, or Electronics line Foundation, was a worldwide coalition of computer users who had embeded a powerful civil liberties coalition aimed at backup free speech on-line and educating differents to the realities and dangers of living in an electronic world. They were constantly lobbying against what they called the Orwellian eavesdropping capabilities of government agencies-particularly the NSA. The EFF was a perpetual thorn in Strathmores side.Sounds like business as usual, she said. So whats this big emergency you got me out of the tub for?Strathmore sat a moment, absently fingering the comp uter trackball embedded in his desktop. subsequently a broad silence, he caught Susans gaze and held it. Whats the longest youve ever seen TRANSLTR take to break a computer code?The question caught Susan entirely off guard. It seemed meaningless. This is what he called me in for?Well She hesitated. We stumble a COMINT intercede a few months ago that took about an hour, but it had a ridiculously long key-ten thousand bits or some liaison like that.Strathmore grunted. An hour, huh? What about some of the boundary probes weve run?Susan shrugged. Well, if you include diagnostics, its obviously longer.How much longer?Susan couldnt cipher what Strathmore was getting at. Well, sir, I tried an algorithm last March with a segmented million-bit key. Illegal loop functions, cellular automata, the works. TRANSLTR still broke it.How long?Three hours.Strathmore arched his eyebrows. Three hours? That long?Susan frowned, mildly offended. Her business concern for the last trio years had bee n to fine-tune the most secret computer in the world most of the programming that made TRANSLTR so fast was hers. A million-bit key was hardly a realistic scenario.Okay, Strathmore said. So even in extreme conditions, the longest a code has ever survived inside TRANSLTR is about three hours?Susan nodded. Yeah. More or less.Strathmore paused as if afraid to say something he might regret. Finally he looked up. TRANSLTRs hit something He stopped.Susan waited. More than three hours?Strathmore nodded.She looked unconcerned. A new diagnostic? Something from the Sys-Sec Department?Strathmore shook his head. Its an outside file.Susan waited for the stop up line, but it never came. An outside file? Youre joking, right?I wish. I queued it last night well-nigh eleven thirty. It hasnt broken yet.Susans jaw dropped. She looked at her watch and then back at Strathmore. Its still spill? Over fifteen hours?Strathmore leaned forward and rotated his monitor toward Susan. The screen was black except for a small, yellowish text box blinking in the middle.TIME ELAPSED 150933 AWAITING KEY ________Susan stared in amazement. It appeared TRANSLTR had been working on one code for over fifteen hours. She knew the computers processors auditioned thirty million keys per second-one hundred cardinal per hour. If TRANSLTR was still counting, that meant the key had to be enormous-over ten billion digits long. It was absolute insanity.Its impossible she declared. Have you checked for misapprehension flags? Maybe TRANSLTR hit a glitch and-The runs clean.But the pass-key must be hugeStrathmore shook his head. model commercial algorithm. Im opine a sixty-four-bit key.Mystified, Susan looked out the window at TRANSLTR below. She knew from experience that it could locate a sixty-four-bit key in under ten minutes. Theres got to be some explanation.Strathmore nodded. There is. Youre not going to like it.Susan looked uneasy. Is TRANSLTR malfunction?TRANSLTRs fine.Have we got a virus?Strathmore shook his head. No virus. Just hear me out.Susan was flabbergasted. TRANSLTR had never hit a code it couldnt break in under an hour. Usually the cleartext was delivered to Strathmores printout module within minutes. She glanced at the high-speed newswriter behind his desk. It was empty.Susan, Strathmore said quietly. This is going to be hard to accept at first, but just discover a minute. He chewed his lip. This code that TRANSLTRs working on-its unique. Its like nothing weve ever seen before. Strathmore paused, as if the countersignatures were hard for him to say. This code is unbreakable.Susan stared at him and almost laughed. Unbreakable? What was THAT supposed to mean? There was no such thing as an unbreakable code-some took longer than others, but every code was breakable. It was mathematically guaranteed that sooner or later TRANSLTR would guess the right key. I beg your pardon?The codes unbreakable, he repeated flatly.Unbreakable? Susan couldnt believe the word had been u ttered by a man with twenty-seven years of code analysis experience.Unbreakable, sir? she said uneasily. What about the Bergofsky Principle?Susan had learned about the Bergofsky Principle early in her career. It was a cornerstone of brute-force technology. It was also Strathmores fervor for building TRANSLTR. The principle clearly stated that if a computer tried enough keys, it was mathematically guaranteed to puzzle the right one. A codes security was not that its pass-key was unfindable but rather that most people didnt have the time or equipment to try.Strathmore shook his head. This codes different.Different? Susan eyed him askance. An unbreakable code is a mathematical impossibility He knows thatStrathmore ran a hand across his sweaty scalp. This code is the product of a brand-new encoding algorithm-one weve never seen before.Now Susan was even more doubtful. Encryption algorithms were just mathematical formulas, recipes for scrambling text into code. Mathematicians and prog rammers created new algorithms every day. There were hundreds of them on the market-PGP, Diffie-Hellman, ZIP, IDEA, El Gamal. TRANSLTR broke all of their codes every day, no problem. To TRANSLTR all codes looked identical, regardless of which algorithm wrote them.I dont understand, she argued. Were not talking about reverse-engineering some complex function, were talking brute force. PGP, Lucifer, DSA-it doesnt matter. The algorithm generates a key it thinks is secure, and TRANSLTR keeps guessing until it finds it.Strathmores reply had the controlled patience of a good teacher. Yes, Susan, TRANSLTR will always find the key-even if its huge. He paused a long moment. UnlessSusan wanted to speak, but it was clear Strathmore was about to drop his bomb. Unless what?Unless the computer doesnt know when its broken the code.Susan almost set down out of her chair. WhatUnless the computer guesses the correct key but just keeps guessing because it doesnt realize it found the right key. Strath more looked bleak. I think this algorithm has got a rotating cleartext.Susan gaped.The notion of a rotating cleartext function was first put away in an obscure, 1987 paper by a Hungarian mathematician, Josef Harne. Because brute-force computers broke codes by examining cleartext for identifiable word patterns, Harne proposed an encryption algorithm that, in addition to encrypting, shifted decrypted cleartext over a time variant. In theory, the perpetual mutation would go over that the attacking computer would never locate recognizable word patterns and thus never know when it had found the proper key. The concept was somewhat like the idea of colonizing Mars-fathomable on an intellectual level, but, at present, well beyond human ability.Where did you get this thing? she demanded.The commanders response was slow. A public sector programmer wrote it.What? Susan collapsed back in her chair. Weve got the best programmers in the world downstairs All of us working together have never ev en come close to writing a rotating cleartext function. Are you trying to tell me some poser with a PC figured out how to do it?Strathmore lowered his voice in an apparent lawsuit to calm her. I wouldnt call this guy a punk.Susan wasnt listening. She was convinced there had to be some other explanation A glitch. A virus. Anything was more likely than an unbreakable code.Strathmore eyed her sternly. One of the most hopeful cryptographic minds of all time wrote this algorithm.Susan was more doubtful than ever the most brilliant cryptographic minds of all time were in her department, and she certainly would have heard about an algorithm like this.Who? she demanded.Im sure you can guess. Strathmore said. Hes not too fond of the NSA.Well, that narrows it down she snapped sarcastically.He worked on the TRANSLTR project. He broke the rules. Almost caused an intelligence nightmare. I deported him.Susans face was blank only an instant before going white. Oh my GodStrathmore nodded. Hes be en bragging all year about his work on a brute-force-resistant algorithm.B-but Susan stammered. I thought he was bluffing. He truly did it?He did. The ultimate unbreakable code-writer.Susan was silent a long moment. But that meansStrathmore looked her dead in the eye. Yes. Ensei Tankado just made TRANSLTR obsolete.