He had showed respect for procedure by calling Sula by her code name, though because they’d trained together he knew her real name perfectly well, just as she knew his despite the fact that, as head of Action Group Blanche, she should refer to him as “Blanche.” Awarding code names had come rather late in the training, and by that time they’d all got used to one another’s genuine identities. Another aspect, Sula realized now, of the amateurishness with which this operation had been set up.
“You’re based in a Terran neighborhood,” said Lord Octavius. “If you were living with Naxids, you might have cause to worry, but your neighbors will have no reason to betray you.”
“How about money or favor?” Sula said as she stirred more honey into her tea. “What if the Naxids offer a cash reward for turning us in?”
Hong gave her a stern look. “Loyal citizens—” he began.
“I want backup identities for my whole team,” she said, stirring. “And everyone else in your group should get them, too.” She raised her spoon and licked it, the flavor of warm clover honey bursting on the tip of her tongue.
For the first time in their acquaintance Hong’s face displayed a moment of doubt. “I’m not sure that’s in the budget,” he said cautiously.
Sula raised her cup of tea to her lips. “Oh, for all’s sake, Blanche,” she said. “Our side coins the money.”
Hong’s decisive look returned. “I’ll push a memorial up to higher authority, shall I?”
“I’ll do the work myself,” Sula said. It was an offer, and also a decision.
She still had her special warrant from the lord governor. Sula used one of the cameras with which the Intelligence Section had equipped Team 491 to take pictures of herself and her group, then put on her uniform and took the funicular to the High City. She flashed her warrant in the Records Office and took advantage of a slight ambiguity in its wording—“require cooperation in the matter of records”—to get herself a desk and the passwords necessary to do her job.
The passwords, strings of long numbers, she recorded with her sleeve camera while no one was looking.
Thus enabled, her task was simple enough that once she had her three backup identities, she saw no reason to stop. By the time the office closed at the end of day, each member of Action Team 491 had four false identities, counting the ones they’d started with.
Sula collected the last of these, the heavy plastic card still warm from the thermo printer, the seal of the government embossed on its surface.
That evening, she memorized the codes she’d printed, destroyed the printout, and thought, I must remember to use these powers only for good.
She told Hong that joke at their next meeting. He frowned, brows knitting. “You’ll do well to remember, Four-nine-one,” he said, “that in the military, irony proceeds from the top.”
Sula straightened. “Very good, my lord.”
“Don’t call me that here.”
“That’s all right. It was irony.”
Hong grunted, eyes fixed on his plate. As was his custom, he had chopped his pastry up into several pieces, which he now commenced to eat with military efficiency, last of all sweeping up the crumbs and devouring those as well.
The day was rainy and he and Sula met indoors. The café was crowded and smelled of damp wool, and the door banged loudly whenever anyone went in and out.
“Still,” Hong admitted, “that’s a good use of initiative, I suppose. You’ll have to give me a list of those names, of course.”
“No,” Sula said. “Absolutely not.”
Hong looked at her in surprise. “What do you mean, no?”
“You don’t need to know our backup identities. We’ll have secure means of communication no matter what names we’re using, so the only people inconvenienced will be the Naxids, when they arrest you and interrogate you and you can’t tell them where to find us.”
Hong didn’t seem annoyed, which Sula might have understood, but rather deeply and sincerely concerned, as if he’d just learned she’d come down with a serious illness.
“Are you all right about this?” he asked. “You’re not having second thoughts about our assignment, are you?”
“None whatsoever,” she said flatly, and held his eyes until he dropped them.
Second thoughts about you, she said to herself, are another matter.
That evening, out of more than merely idle curiosity, Sula used the display and touch-keypad in the surface of the old desk in a corner of her apartment’s front room, and logged onto the archives at the Records Office to see if her passwords still worked. They did.
But she knew they wouldn’t work much longer: passwords of this sort were changed frequently as a matter of routine, and when the Naxids arrived they might well demand exclusive control of the system.
“Ada,” she said to Engineer/1st Spence, calling her by the cover name assigned her by the Fleet. “I can use your advice.”
Spence brought a chair to where Sula worked, and sat. She was a short, sturdy woman of around thirty, with short straw hair and a pug nose. “What do you need?”
“I’m in the Records Office data system. And what I’d like is to make certain that I can keep my access even after they change the passwords.”
Spence was surprised. “Is that legal?”
Sula suppressed a laugh. “I have a warrant,” she said, and hoped her face was straight. “The problem is that the Naxids aren’t going to honor it.”
Spence considered the display. “Can you get into the directory?”
Sula gave the command, and a long list, thousands of files, began rolling across the desktop.
“Apparently I can,” Sula said.
“System: halt,” Spence ordered. “System: find file Executive.”
Two file names glowed in Sula’s display, one a backup of the other.
“There you are,” said Spence. “You want to rewrite the executive file to give you permanent access.”
“Will it let me?”
“I don’t know. Whose passwords are you using?”
“Lady Arkat,” Sula said. “She’s the head of System Security.”
Spence laughed. “You’d think the head of security would have thought to change her passwords the second you were out the door.”
“She’s rather old. Maybe she’s a creature of habit.”
“Or maybe she’s, well, on our side.”
Sula thought that the elderly Torminel was not as sympathetic as all that, but conceded she might be wrong.
“System,” she ordered, “open file Executive.”
The file sprawled out before her, thousands upon thousands of if/then statements. Sula gave a low whistle.
“How good are you at programming?” she asked.
“I use computers,” Spence said, “I don’t program them.”
“My programming courses were a while ago,” Sula said. Though she did some programming now and again, her skills were hardly first-class.
“Back up everything,” Spence advised, “go very slowly, and make use of any help files.”
“Right,” Sula said, and backed up the executive file first thing, both onto the Records Office computer and into the system in her desk. She made herself a pot of strong, sweet tea and prepared for a long night.
“I’m very good at puzzles,” she reminded herself.
It was the copy on her desk that she worked with. Fortunately the actual changes that she wanted to make were minor, even though they had far-reaching implications. Whenever you change the password, send me a copy. How complicated could such an order be?
She told the computer to send the copy to her hand comm, the one she carried with her. After a few catastrophic syntax errors, the program seemed to run, at least in Sula’s desk.
Sula took a deep breath and scrubbed her palms on her thighs, drying any hypothetical sweat. She would now have to load her altered program back into the computer at the Records Office. She pictured the thousand consequences of this attempt goin
g wrong, Hong’s fury at one of his secret team being exposed, official reprimand, scathing reports in her file.
She sent her altered program to the Records Office and held her breath. Nothing happened.
Sula slowly let her breath out, then reached for her tea. It had turned cold, and the thick liquid was like a stripe of molasses on her tongue. She went to the kitchen for a few moments to reheat her tea, and when she came back, nothing had changed.
She sent herself some simple mail—“hello”—using the Records Office computer, and opened her hand comm to discover the mail waiting for her.
The next test was to see if she could create a set of identification. If she succeeded, she could simply mail the documents to herself here at the apartment. She began work, but stopped when an incoming message icon blinked onto her hand comm. She triggered it, and a text message appeared on the small screen.
My Lady Arkat,
We have detected an attempt to rewrite the Executive File of the main computer at the Records Office. This attempt occurred at 01:15:16. We will erase the corrupt copy and reload the Executive File from backups.
You have been assigned a new, temporary password: 19328467592.
Please change your temporary password to a permanent password of your choice as soon as you arrive at your desk in the morning.
In service to the Praxis,
Ynagarh, CN5, Assistant Data Administrator
Words leapt to Sula’s lips, words that would disconnect her at once from the Records Office computer.
She didn’t utter them.
Instead she tried to work out what had just happened. Though the intrusion had been detected almost ten minutes ago, she was still inside the computer. If the administrators had bothered to check to see who was connected remotely, they would have found her to be Lady Arkat, their own chief, a fact that would have made them reluctant to disconnect her.
Whatever the case, she still had access to the Records Office computer. She had Lady Arkat’s temporary password, which would be good for the next few hours, until Lady Arkat arrived at the office and changed it. But after that Sula would be frozen out, because the executive file that Sula had ordered to send copies of the new password had been erased.
As long as Sula stayed connected to the computer, she was still able to make changes, at least as long as she avoided whatever error it was that had caused her altered program to be detected in the first place.
She took another sip of her tea, jasmine and citrus honey gone tepid, and wondered what her error could have been.
Sula looked again at the error message. 01:15:16. They had her intrusion down to the second.
That gave her the first clue. Some rummaging in administration files revealed no less than six automated messages that had been sent toAssistantAdministratorYnagarh, each stating that the executive file had been replaced by one of a later date.
“Ah. Hah,” Sula said.
It had been the file’s date that had given her away. But in that case, why six messages, and not one?
The automated system had sent six messages because she had been detected in no less than six different ways. A second mentioned that the file size had changed. The other four informed Ynagarh that a change in the “hash signature” had been detected.
What the hell are those? Sula wondered. She turned to ask Spence if she knew, but Spence had long since gone to bed.
First things first, Sula decided. Dates were something she understood.
She checked the date on the executive file that had been loaded over her altered file, and found that it had last been changed nine years before. Nine years. The file itself had been created over six thousand years ago. It was obviously stable and required very little tweaking. No wonder her executive file had set alarm bells ringing.
Sula reheated her tea again and drank a cup while she contemplated the problem. Could the answer be as simple as changing the date on her file? She had the very high privileges that came with Lady Arkat’s account, and found that it wasn’t a problem: she changed the date on the file to nine years before, and when she made a backup file onto her own computer, the altered date didn’t change back to the real one.
And a message would go to the administrators if the file’s size changed: that was clear from Ynagarh’s messages. The program that she loaded into the Records Office computer would have to be the exact same size as the one there now.
She clenched her fists in a cold frenzy. Now she was going to have to go through the program line by line in hopes she could pare out enough redundant programming to make up for the lines she’d added. This was maddening…
Rather than even contemplate this task, she dug for a frantic hour through Lady Arkat’s help files and searched through the program’s architecture, and in time discovered what a hash signature was.
The ancient executive file was compiled into a binary form that, in addition to performing its various tasks, was itself an integer. By performing a calculation that was very easy to do in one direction, but difficult to backtrack—say dividing by pi and using the first thousand digits of the remainder—the resulting arithmetical signature—the “hash”—could identify even tiny changes in the file’s size.
Sula opened the file again and let the lines of code scroll in front of her bewildered eyes. She was too tired to think properly. She rose from her chair, stretched, and flapped her arms in hope of bringing a surge of blood into her weary mind. She stepped to the window and gazed down at the street below, the busy life of day much subdued now, the haunt of street cleaners and Torminel.
Sula’s eyes lifted to the eastern horizon, soon to turn pale green with rising of Shaamah. She had bare hours in which to perform her calculations. Somehow, she had to reverse-engineer the calculation that produced no less than four wildly different hash signatures, without knowing what the algorithms were or where they could be found.
She dragged her weary feet back to her desk. The executive file was ancient, she thought. It was so old it might have been written by the Shaa…
And then she stopped dead, as she remembered the fondness of the Shaa for prime numbers…
All weariness sizzled away as she made a galvanic leap into her chair. A list of prime numbers was available in a public database, and she disregarded the first thousand as too small, then seized the next nine thousand and ran them against all values in the executive file.
One…The first match appeared in the display.
Two…
Three…
Four.
All the hash numbers were located in the same part of the program, which was clearly the part of the program having to do with alarms and security. She couldn’t have found the alarm program with a month of random searching.
The Shaa weren’t so damned smart, she concluded.
Sula scanned the program with great interest. There were the access codes, which were the key, and the alarm files, which were the lock, and there were the log files that recorded all changes in the system, which was a record of which key went with which lock, and when.
What she had to do, it turned out, was change both the lock and the key. And then the records had to be changed to read, This has always been the lock, and This has always been the key.
In the next hour Sula added extra code to the executive file. In order, this set permissions on the log files to unwritable, which would prevent her manipulations from being detected, deleted the last line of the log file, which otherwise would have included her previous command, sent a copy of any new password to Sula’s comm, and then set permissions on the log file back to writable, which returned everything to normal
She prepared all the hashes for the alarm files.
Then Sula created a new program that would load her own executive file into the computer at the Records Office, something that would manage the whole procedure a lot faster than could Sula by giving orders or typing commands.
The program had a number of familiar commands, and some that were new:
it set permissions on the log files to unwritable, deleted the last line of the log file, engaged all diagnostic programs, updated size and hash information on all alarms, copied her executive file over the old one, altered the dates of creation and modification on her new file to those of the old one, then ended all diagnostic programs and reset permissions on the log files to writable.
She tested the operation several times in her own computer. Then, holding her breath, she triggered her new program.
Sweat prickled on her forehead as she looked at Assistant Administrator Ynagarh’s messages, and saw no message alerting him to anything amiss with his computer.
She let out a long breath. It seemed that she’d got away with it.
Dawn was greening in the east. Sula made a last, obsessive scan of everything once more, just to make certain the file was as she left it, and then broke the connection. She told the apartment’s system to wake her in the morning just before the Records Office opened for business, so that she could be sure to get into the computer on Lady Arkat’s temporary password before it was changed.
As she prepared for bed Sula looked at herself in the mirror and was appalled. Her eyes had deep shadows under them, her hair was stringy, and there were blooms of sweat under her arms. She couldn’t abide sleeping in such condition, so she took a thorough shower. She went into the bedroom she shared with Spence, groped her way to her bed, and fell into it.
For once, oblivion did not take long to reach her mind.
It seemed as if she took only a few breaths before the alarm chimed her awake, and she threw on clothing and ran to the desk. It was broad, brilliant daylight. Spence was making herself breakfast, and Macnamara had already left on his morning errands—as the team’s courier, his task was to check certain public places to find if any messages had been left for the team, and he’d been provided with a two-wheeled vehicle for the purpose.
Sula called the Records Office and used Lady Arkat’s temporary password to gain access to the main computer. Spence silently brought to her desk a cup of heavily sweetened coffee, shortly followed by a toasted muffin and a pot of jam.
The Sundering Page 30
