Chapter 5
“Where is everyone?” Susan wondered as she crossed
the deserted Crypto floor. Some emergency.
Although
most NSA departments were fully staffed seven days a week, Crypto was generally
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 too
valuable a commodity at the
NSA to risk losing them to burnout.
As Susan traversed the floor,
TRANSLTR loomed to her right.
The sound of the generators eight stories below sounded
oddly ominous today. Susan never liked being
in Crypto during off hours. It was like being trapped alone in a cage with some grand, futuristic beast. She quickly
made her way toward the commander’s office.
Strathmore’s glass-walled workstation, nicknamed “the fishbowl” for its appearance when the drapes were open, stood
high atop a set of catwalk stairs on the back wall of Crypto.
As Susan climbed the grated steps, she gazed upward at Strathmore’s thick, oak door. It bore the NSA seal–a bald eagle fiercely
clutching an ancient skeleton key. Behind that door sat one of the greatest
men she’d ever met.
Commander
Strathmore, the fifty-six-year-old deputy director
of operations, was like a father to Susan. He was the one who’d hired her, and he was the one who’d made the NSA her home. When Susan joined the NSA over a decade ago, Strathmore was heading the Crypto Development Division–a training ground for new cryptographers–new male cryptographers. Although Strathmore never tolerated
the hazing of anyone,
he was especially protective of his sole female
staff member. When accused of favoritism, he simply replied with the truth: Susan Fletcher
was one of the brightest
young recruits he’d ever seen, and he had no intention
of losing her to sexual
harassment. One of the cryptographers foolishly decided to test Strathmore’s 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 only panties.
As it turned out, one of the cryptographers had digitally scanned a photo from a pornographic magazine
and edited Susan’s head
onto someone else’s body. The effect had been quite convincing.
Unfortunately for the cryptographer responsible, Commander Strathmore did not find the stunt
even remotely amusing. Two hours
later, a landmark memo went out:
EMPLOYEE CARL AUSTIN TERMINATED FOR INAPPROPRIATE CONDUCT.
From that day on, nobody
messed with her; Susan Fletcher was Commander
Strathmore’s golden girl.
But Strathmore’s 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 number of unorthodox and highly successful intelligence 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 surrounding the NSA’s difficult decisions and to act
without remorse in the interest
of the common good.
There was no doubt in anyone’s
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 Susan’s
arrival at the NSA, Strathmore had skyrocketed from head of Crypto Development to second-in-command of the entire NSA. Now only one man outranked Commander Strathmore there–Director Leland Fontaine, the mythical
overlord of the Puzzle
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 among giants, but Strathmore didn’t seem to care. He argued
his ideas to the director with all the restraint of an impassioned boxer. Not even the President of the United States dared challenge Fontaine the way Strathmore did. One needed political
immunity to do that–or,
in Strathmore’s case, political
indifference.
* * *
Susan arrived
at the top of the stairs. Before she could knock, Strathmore’s 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 hard-nosed efficiency and demand for perfection. His gray eyes usually suggested a confidence and discretion
born from experience, but
today they looked wild and unsettled.
“You look beat,” Susan said.
“I’ve been better.” Strathmore sighed.
I’ll say, she thought.
Strathmore looked as bad as Susan had ever seen him. His thinning
gray hair was disheveled, and even in the room’s crisp air-conditioning, his forehead
was beaded with sweat. He looked like he’d slept in his suit. He was sitting behind a modern desk with two recessed
keypads and a computer
monitor at one end. It was strewn
with computer printouts and looked like some sort of alien cockpit
propped there in the center of his curtained chamber.
“Tough week?” she
inquired.
Strathmore shrugged. “The usual. The
EFF’s all over me
about civilian privacy rights
again.”
Susan chuckled.
The EFF, or Electronics Frontier Foundation, was a worldwide coalition of computer
users who had founded a powerful
civil liberties coalition aimed at supporting
free speech on-line and educating others 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 Strathmore’s
side.
“Sounds
like business as usual,” she said. “So what’s this big emergency you got me out of the tub for?”
Strathmore sat a moment, absently
fingering the computer trackball embedded in his desktop. After a long silence, he caught Susan’s
gaze and held it. “What’s the longest
you’ve ever seen TRANSLTR
take to break a code?”
The question caught Susan entirely off guard.
It seemed meaningless. This is what he called
me in for?
“Well…”
She hesitated. “We hit a COMINT intercept a few months ago that took about an hour, but it had a ridiculously long key–ten thousand bits or something like that.”
Strathmore grunted. “An hour, huh? What about some of
the boundary probes we’ve
run?” Susan shrugged. “Well, if
you include diagnostics, it’s obviously longer.”
“How much longer?”
Susan couldn’t
imagine what Strathmore was getting at. “Well, sir, I tried an algorithm last March with a segmented million-bit key. Illegal looping
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 job for the last three years had been 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. “TRANSLTR’s 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. “It’s an outside file.”
Susan waited
for the punch line, but it never came. “An outside file? You’re
joking, right?” “I wish. I queued
it last night around eleven
thirty. It hasn’t broken yet.”
Susan’s
jaw dropped. She looked at her watch and then back at Strathmore. “It’s still going?
Over fifteen hours?”
Strathmore leaned forward and rotated his monitor toward Susan. The screen
was black except for
a small, yellow text
box
blinking in the middle.
TIME
ELAPSED: 15:09:33
AWAITING KEY:
Susan stared in amazement. It appeared TRANSLTR had been working on one code for over fifteen
hours. She knew the computer’s processors auditioned thirty
million keys per second–one hundred billion per hour. If
TRANSLTR was still
counting, that meant the
key had to be enormous– over
ten billion digits long. It was absolute
insanity.
“It’s impossible!” she declared.
“Have you checked
for error flags? Maybe TRANSLTR hit a glitch
and–”
“The run’s clean.”
“But the
pass-key must be huge!”
Strathmore shook his head. “Standard commercial algorithm. I’m guessing 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. “There’s got
to be some explanation.” Strathmore
nodded. “There is. You’re not going to like it.”
Susan looked
uneasy. “Is TRANSLTR malfunctioning?” “TRANSLTR’s 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 couldn’t
break in under an hour. Usually the cleartext
was delivered to Strathmore’s printout module within minutes.
She glanced at the high-speed printer behind his desk. It
was empty.
“Susan,”
Strathmore said quietly.
“This is going to be hard to accept at first, but just listen a minute.” He chewed his lip. “This code
that TRANSLTR’s working
on–it’s unique. It’s
like nothing we’ve ever seen before.” Strathmore paused, as if the words 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 code’s unbreakable,” he
repeated flatly.
Unbreakable? Susan couldn’t believe the word had been uttered
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 Strathmore’s inspiration for
building TRANSLTR. The principle clearly
stated that if a computer tried enough keys, it was mathematically guaranteed to find the right one. A code’s security was not that its pass-key
was unfindable but rather that most people
didn’t have the
time or equipment to try.
Strathmore shook his head. “This code’s
different.”
“Different?” Susan eyed him askance.
An unbreakable code is a mathematical impossibility!
He knows that!
Strathmore ran a hand across his sweaty scalp.
“This code is the product
of a brand-new encryption
algorithm–one we’ve never seen before.”
Now Susan was even more doubtful.
Encryption algorithms were just mathematical formulas, recipes for scrambling text into code. Mathematicians and programmers 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 don’t understand,” she argued. “We’re not talking
about reverse-engineering
some complex function,
we’re talking brute force. PGP, Lucifer,
DSA–it doesn’t matter. The algorithm
generates a key it thinks is secure, and TRANSLTR
keeps guessing until it finds it.”
Strathmore’s reply had the controlled patience of a good teacher. “Yes, Susan,
TRANSLTR will
always
find the key–even if it’s huge.” He paused
a long moment. “Unless…”
Susan wanted
to speak, but it was clear
Strathmore was about to drop his bomb. Unless what?
“Unless the computer doesn’t know when
it’s broken the code.”
Susan almost fell out of her chair. “What!”
“Unless
the computer guesses
the correct key but just keeps guessing
because it doesn’t realize it found the right key.” Strathmore looked
bleak. “I think this algorithm has got a rotating
cleartext.”
Susan gaped.
The notion of a rotating cleartext function was first put forth 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 ensure 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 commander’s response was slow.
“A public sector programmer wrote it.”
“What?” Susan collapsed back in her chair. “We’ve
got the best programmers in the world downstairs! All of us working together have never even come close to writing a rotating
cleartext function.
Are
you trying to tell me
some punk with a
PC figured out how to do it?”
Strathmore lowered his voice in an apparent effort
to calm her. “I wouldn’t call this guy a punk.”
Susan wasn’t 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 brilliant
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.
“I’m sure you can guess.”
Strathmore said. “He’s 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.”
Susan’s face
was blank only an instant
before going white. “Oh
my
God…”
Strathmore nodded. “He’s been bragging all year about his work on a brute-force–resistant algorithm.”
“B-but…” Susan stammered. “I thought he was bluffing.
He actually did it?” “He did. The ultimate unbreakable code-writer.”
Susan was
silent a long moment. “But… that
means…”
Strathmore looked her dead in the eye. “Yes. Ensei Tankado just made TRANSLTR
obsolete.”
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