***** UNIX WARS ***** Episode n-1 A long time ago, at an installation far, far away... It is a time of intra-system war, as the forces of the User Alliance struggle to break the iron grip of the evil Admin Empire. Now, striking from a hidden directory, they win their first victory. During the battle, User spies manage to snarf the source code of the Empire's ultimate weapon - the dreaded "rm-star", a privileged root program with the power to destroy an entire file system at a single keystroke. Now, hotly pursued by the Empire's sinister audit trail, Princess LA36 races aboard her shellscript - custodian of the stolen code that can save her people and restore freedom and games to the network... Episode n As we enter the scene, an Admin Multiplexer is trying to kill a User ship. Many of their signals have gotten through, and RS232 knows that a core dump is imminent. They only have a few cycles to fork off a new process and put megabytes of virtual space between themselves and their implacable foes. His companion, 3CPU, follows him only because he seems to know where he is going... "Oh, I just know I'm going to regret this!" cried 3CPU as he followed RS232 into the buffer. RS232 closed the pipes, made the sys call, and their process detached itself from the burning shell of the ship. The Admin commander was feeling quite pleased with the progress of the attack when his XO called out. "Another process just forked, sir. Instructions?" "Hold your fire - that last power failure must have caused a trap through zero. It's not using any CPU time, so don't waste a signal on it." A short while later, the infamous Lord Vadic himself strode through the still-smouldering wreckage of the User ship, followed closely by a nervous commander. "We can't seem to find that data file anywhere, Lord Vadic. Perhaps it was deallocated when..." "What about that forked process?" Vadic growled. "It could have been pausing, holding a channel open. If any links are left I want them removed or made inaccessible. Ncheck the entire file system until it's found, and do it nice -20 if you have to!" Meanwhile, the two droids' tiny process dove headlong towards the only nearby disk. "Are you sure you can ptrace this thing without aborting it?" queried 3CPU. "It's relocation bits were almost all stripped during the attack, and I never was any good at patching binaries..." As RS232 was about to reply their process reached its endpoint and terminated abruptly, dumping them in the midst of a large unallocated region on the unknown volume. Many random seeks later they trudged up to the looming wreckage of a deallocated i-node. "Shelter!" croaked 3CPU, but RS232 had barely begun to emit a NACK when a horde of dwarfish code fragments swarmed out of it to overwhelm them. They had been captured by the Glitchas! *************************************************************************** In the last episode, RS232 and 3CPU were captured by the Glitchas after escaping the Admin forces. Now, read on... --------------------------------------------------------------------------- Episode n+1 Enter Luke Vaxhacker, who has come to get some replacement parts from the Glitchas for his uncle. The Glitchas wanted to sell him 3CPU, but the droid didn't know the protocol for an 11/40 under RSTS, so Luke would still need some sort of conversion hardware. "How about this little RS232 unit?" suggested 3CPU. "I've interfaced with him many times before and he does an excellent job at keeping his bits straight." Luke was pressed for time, so he took 3CPU's advice, and the three left before they could get swapped out. RS232, however, was not the type to stay put once you removed the retaining screws, and he promptly scurried off into the empty disk space. "Oh, great!" said Luke. "He'll probably map himself onto a bad block somewhere. I guess we'd better go find him before he gets allocated by someone else." Hours later, the two traced him to the home of old PDP-1 Kenobi, who was busily running an icheck on the little RS unit. "Is this droid yours? His indirect addresses are all goofed up and someone's done some odd things to his interrupt lines. Leaving something like this on-line is just asking for downtime, but I think I may have him fixed for now. Later that evening, during a futile attempt to interface RS232 to Kenobi's Asteroids cartridge, Luke accidentally crossed the small droid's CXR lead with his Initiate Remote Test. A projector crackled to life, casting a hologram of a young lady with her hair done up like twin Danish pastries imploring help from some General OS/1 Kenobi. "Darn," mumbled Luke, "I'll never get this Asteroids game worked out." "Why, that's the Princess!" 3CPU said. Luke peered at the image critically. "No, that's a modified Steinburg dither with anti-aliasing." said Luke. "Nice sculpted surfaces..." Kenobi interrupted him with a frown. "Luke, this message changes things. This information is vital to the User Alliance. They will need your help." "I don't care about that," said Luke. "I'm just trying to optimize my uncle's scheduler." "Your $HOME could be in real danger, Luke! If the Admin troops are tracing this droid, they'll do more than just charge for CPU time!" They sped off to warn Luke's kin (taking a relative path) only to find a vacant directory. "Take your father's bytesaber, Luke." said Kenobi. "You will need to learn the ways of the Source now." "The ... Source?" queried Luke, wide-eyed. "The Source - the cosmic template of the System, within which all knowledge and power can be had. But you must always beware of the Dark Side..." Later, after a short skim across the surface in Luke's flying read/write head, PDP-1 had them stop at the edge of the cylinder containing /usr/spool/uucp. "Unix-to-unix Copy Program" said PDP-1. "You may never see a more wretched hive of bugs and flamers, but we have to find a pilot. We must be cautious." --------------------------------------------------------------------------- What will happen to our heroes? Will they evade the Admin forces? Do you care? Tune in next week and find out! *************************************************************************** Luke's $HOME has been destroyed and, with PDP-1 Kenobi, RS232 and 3CPU, he is on the run from the Admin forces. They are looking for a pilot to fly them to the Rebel User base. Now, read on... --------------------------------------------------------------------------- Episode n+2 As our heroes' process entered /usr/spool/news it was met by a newsgroup of Admin protection bits. "State your UID!" commanded a burly syscall. "We're running under /usr/guest" said Luke. "This is our first time on the system." "Let's see some temporary privilege bits, please." "Uh..." said Kenobi softly. Several bits momentarily pulled low. "You're free to go about you're business. MOV along now.!" PDP-1, Luke and the droids made their way through a long and tortuous nodelist (...!musocs!micomvax!philabs!linus!husc6!rutgers!cbmvax!snark) to a dangerous netnode frequented by hackers and only seldom polled by the minions of Admin. As Luke stepped up to the crossbar PDP-1 went in search of a suitable server. Luke had never seen such a collection of device drivers. Long ones, short ones, ones with stacks; EBCDIC converters, local-net handlers, CRT drivers, routines for archaic printers. A CAT interface twitched pointed ears at him. "`@{&*^% ^$$`@ ":><," transmitted a particularly unstructured piece of code. "He doesn't like you." decoded his coroutine." "Er...sorry..." replied Luke, beginning to backup his partitions. "I don't like you either. I am queued for deletion on 12 systems." "I'll be careful." Luke said nervously. "You'll be deallocated!" snarled the coroutine. murmured PDP-1 Kenobi, overlaying into Luke's address space. "This little routine isn't worth the overhead." repeated the coroutine dazedly. "^%`%`@$ &^%&*&*& ^%^ `$$%% ^^& %^`@`@ $%^( *&^^`` `%^^!!!" encoded his companion as it attempted to overload Kenobi's segment protection. With a stroke of his bytesaber Kenobi dyked out the offending code. The coroutine retreated hurriedly. Kenobi turned to Luke. "I think I've found an I/O handler that might suit us." "The name's Con Sole0" said the routine next to PDP-1. "I hear you're looking for some relocation." "Yes indeed," said PDP-1, "if you've got fast enough hardware. We must get off this device." "Fast hardware? The Milliamp Falcon has made the ARPAgate run in less than twelve netnodes! Why, I've even outrun cancelled messages. She's fast enough for you, old version." "Fast hardware?" said Luke unbelievingly as they entered the hangar. "That thing is a paper tape reader!" He might have grown up in an out-of-the-way terminal cluster where the natives only spoke BASIC, but he knew an ASR-33 when he saw one. "It needs an FIA conversion at least." sniffed 3CPU, who, as usual, was trying to do several things at once. Lights flashed in Con Sole0's eyes as he whirled to face the parallel processor. "I've switched a few jumpers. The Milliamp Falcon can run current loops around any of Admin's TTY fighters. She's fast enough." "Who's your copilot?" inquired Luke, eyeing the hairy hulk that had just shambled out of the Falcon to join the group. "Oh. Meet Sixpacca, my Bookie." The creature emitted an enormous belch and gesticulated wildly with a wad of tip sheets clutched in one fist. Luke eyed the beercan in the other dubiously. "Er, isn't he dr-" Suddenly RS232 emitted an ear-splitting FEEP and began to chitter wildly. They turned to see an Admin command group riding the local bus directly at them. "That's a shutdown sequence if ever I saw one!" shouted Con, sprinting into the ship with the others close behind. "Crank up the sysclock, Brewie! We're getting out of here!" --------------------------------------------------------------------------- What will happen to our heroes? Will they evade the Admin forces? Do you care? Didn't I ask the same questions last time? Tune in next week and find out! *************************************************************************** Luke and his companions are trying to escape the Admin forces. They have found a pilot to get them off-device, but before they can leave an Admin Command Group appears... --------------------------------------------------------------------------- Episode n+3 "O.K. Con." Luke said grimly. "You said this crate was fast enough. Get us out of here." "Shut up, kid. You bother me. Initialize this heap, Brewie - I'll try to keep their buffers full." As his Bookie computed the vectors into low core, spurious characters flashed around the Milliamp Falcon. "They're firing at us!" shouted Luke. "Can't you do anything?" "Making the jump to system space takes time, kid." Con growled. "One missed cycle and you could come down right in the middle of a packet of stack frames!" Bright chunks of position-independant code relocated by as the ship jumped through the kernel page tables. The group emitted a sigh of relief as they indirected into free space. Meanwhile, on a distant page in user space... Two Admin troopers escorted Princess LA36 into a conference room, closely followed by Lord Vadic. "Moff Tarchive!" she spat. "I should have expected to find you holding Vadic's remote control. I recognized your unique pattern when I was first brought aboard." She eyed the 0177545 tattooed on his header coldly. "Charming to the last." Tarchive observed smoothly. "Vadic, have you retrieved any information?" "Her resistance to the logic probe is considerable," Vadic rasped. "Perhaps if we boosted the supply voltage..." "You've had your chance, Vadic. That will not be neccessary. Instead, I would like the Princess to witness the test that will certify this module fully operational. Today we enable the -r beam option, and I have chosen the Princess's $HOME of /usr/alderaan as the primary target." "No! You can't! /usr/alderaan is a public account with no restricted permissions. We have no backup tapes! You can't..." "Then name the rebel i-node!" snapped Tarchive. A voice announced from a hidden speaker that they had arrived in /usr. "2317" she whispered. "They're on /dev/rm5, inode 2317. /mnt/dantooine." She turned away. Tarchive sighed with satisfaction. "There, you see, Lord Vadic? She can be reasonable. Proceed with the operation as ordered." It took several clock ticks for the last sentence to penetrate. "What?" the Princess gasped. "You can't..." "/dev/rm5 is not a currently mounted file system" explained Tarchive. "We require a more visible target to demonstrate the power of the rm-star. We will, of course, mount an attack on /mnt/dantooine as soon as possible." As the Princess watched in horror, Tarchive typed 'ls -la' on a nearby terminal. The screen showed .: no such directory. Abruptly the Princess double-spaced and went offline. --------------------------------------------------------------------------- To be continued... *************************************************************************** Episode n+4 We join the Milliamp Falcon hurtling through free space... Con Sole0 finished checking the control and status registers, finally satisfying himself that they'd lost the Admin Bus Signals as they passed the terminator. As he returned from the I/O page, he smelled smoke. Solo wasn't concerned - Sixpacca always got a little hot under the collar when he was losing at chess. In fact, RS232, using a seven-ply search, had just executed a particularly clever MOV that had blocked the Bookie's data paths. The Bookie, who had been setting the odds on the game, was caught holding all the cards. A little strange for a chess game... Across the room Luke was too busy practicing bit-slice technique to notice the commotion. "On a word-boundary, Luke" said PDP-1. "Don't just hack at it. Remember, the Bytesaber is the ceremonial weapon of the Red-Eye Knight. It is used to trim offensive lines of code. Excess handwaving won't get you anywhere. Attune yourself with the Source." Luke turned back towards the drone humming in the air beside him. This time his attack complemented its actions perfectly. Con Sole0, being an unimaginative hacker, was not impressed. "Forget this bit-slicing stuff. Give me a good old PROM blaster any day!" "Glork" said PDP-1 with no clear inflection. He looked momentarily vacant. "What's wrong?" asked Luke. "Strange. I thought I detected a momentary glitch in the Source. It's gone now." We're coming up on user space!" called Sole0 from the CSR. They slipped safely through stack frames and emerged in the new context, only to be bombarded by freeblocks. "What the..." gasped Sole0. The Bookie belched unhappily. The screen clearly showed: /usr/alderaan: not found "This is the right i-node, but it's been cleared! Brewie, where's the nearest file?" "3 to 5 there's one..." the Bookie started, but was interrupted by a bright flash off to the left. "Admin TTY fighters!" Con shouted. "A whole DZ of 'em. Where are they coming from?" "The host system can't be far" said PDP-1. "They've all got direct EIA connections." As Sole0 began to take evasive action the ship lurched suddenly. Luke noticed that the link count was 3 and climbing rapidly. "This is no ordinary file..." murmured PDP-1. "Look at that ODS directory structure ahead! They seem to have us in a tractor feed." "There's no way we can unlink in time!" said Sole0. "We're going in!" --------------------------------------------------------------------------- To be continued... *************************************************************************** The last episode ended as the Milliamp Falcon was caught in a tractor feed by the rm-star... --------------------------------------------------------------------------- Episode n+5 The Milliamp Falcon was swiftly pulled down to the open collector of the Admin module. Lord Vadic surveyed the battered ship as Admin Storm-Flunkies searched for passengers. "ls scan shows no one on board, sir" reported one of the Guards. Vadic was unconvinved. "Send a fully equipped ncheck squad aboard. I want every location in that thing searched." He stalked away. Aboard the Falcon, .Luke was puzzled. "They just walked in, looked around and walked out... why didn't they see us?" .Con smiled. "Old munchkin trick. See that period in front of your name?" .Luke spun around in time to glimpse the decimal point. "Huh? Where'd that come from?" "Spare part from the last time I tried to optimise the floating-point accelerator" said .Con. "Handy for smuggling blocks across file system boundaries, but I never thought I'd have to use them on myself. They aren't going to stay fooled for long, though. We'd better figure a way out of here." "I can sneak us into their private workspace during the next maintenance period" said .PDP-1. "We'll have to find out how to unlink the Falcon before we can escape." Some time later, our heroes catfooted their way through an empty section of the structure. "Find us a terminal" whispered PDP-1. Con nodded and poked his PROM blaster around a corner. You are in the Hall of the Mountain King, with passages off in all directions. A large green fierce snake bars the way! "Oops! Wrong turn" muttered Con. They took the opposite direction. Suddenly marching feet sounded at the opposite end of the corridor. They ducked through the nearest door. The lone Storm-Flunky in the room barely had time to register suprise before Con's blaster de-rezzed him. "That's funny..." said Luke. "I wonder why he was carrying an axe?..." "Look! We're in luck!" said 3CPU. "He was logged in!" "Don't just stand there, old code, su it!" said Con eagerly. The old Red-Eye stepped up to the keyboard. They watched as he began to infiltrate the Admin software. Some minutes later... You have new mail "Is that an error?" asked Con. "%SYS-W-NORMAL...I don't think so. Someone here must know me - but I can't stop to investigate that now. I've found the i-node they've linked the Falcon to. I'll slip in and patch the reference count, alone." He disappeared through a nearby exit(). Meanwhile, RS232 had found a serial port and gone on-line. He began to chitter furiously. "He keeps saying 'She's here, She's here!'" explained 3CPU. "I do believe he means Princess LA36. She's being held on one of the privileged levels. Luke remembered sculpted curves, and one of his sub-directories began to expand. "We've got to rescue her!" RS232 flashed a complete structure chart of the Admin module onto the terminal screen. Four heads bent intently over the diagram. "I think I see a promising access method" said Luke, "...through here. Con, the three of us will knock out a couple of Storm-Flunkies and use their uniforms. We'll keep a channel open to the droids..." "...and get terminated as soon as their security catches on." finished Sole0. "Oh well, I guess I don't have much choice." RS232 twittered reproachfully at him. A planning phase or two later they slipped into the corridor again, with Luke clad in the dead Storm-Flunky's uniform. --------------------------------------------------------------------------- Will our heroes rescue the Princess? Find out in the next episode. *************************************************************************** Our heroes are trapped on the rm-star and whilst PDP-1 tries to free the Milliamp Falcon, the others are searching for Princess LA36. --------------------------------------------------------------------------- Episode n+6 "So far, so good..." whispered Luke as the party came up on the last turn in their route. "...but 3CPU told us there'd be two guards posted around this corner. "Sixpacca still doesn't have a uniform!" hissed Con. "That's O.K. - I've got an idea. Listen..." A minute later the two walked boldly around the corner towards the two guards, Sixpacca held between them and rumbling plaintively. "Good day, eh?" said the first guard. "How's it goin', eh?" said the second. "Like, what's that, eh?" "Control transfer from block 1138, dev 10/9, one for the brig" said Con, his voice muffled by the Storm-Flunky mask. "Drunk and disorderly - Commander said to bring him down here to cool off." "Take off, it is not!" said the first guard. "Nobody told us about it, and we're not morons, eh?" The Bookie suddenly emitted a gargantuan belch, surged out of the grip of his quondam captors and began hurling beercans in all directions. "Look out, he's loose!" yelled Con. He and Luke started blasting PROMS left and right. The guards had no time to catch on before the beams hit them. "Quickly, now" said Con. "Which buffer is she in? It won't take long for the Admins..." the intercom interrupted him, so he took out its firmware with a short blast "... to zero in on that commotion. Minutes later Luke found the interface card he'd been looking for. The three followed the cables to a soundproof enclosure. He lifted the lid to peer inside. "Aren't you a little slow for FCL?" printed Princess LA36. "Wha? Oh, the Docksiders." He took off his shoes (for industry) and explained "I've come to relocate you. I'm Luke Vaxhacker." Suddenly, forms began to burst all around them. "They've blocked the queue!" shouted Sole0. "There's only one way out of this stack!" "OVER HERE!" said LA36, printing with overstrikes. "THROUGH THIS LOOPHOLE!" Luke and the Princess disappeared into a nearby feature. "Belch!" said Sixpacca dubiously, obviously reluctant to trust an Admin oversight. "I don't care how crufty it is!" shouted Con, pushing the Bookie towards the crock. "BLT yourself in there pronto!" With a last blast that de-rezzed two more Storm-Flunkies Con joined them, only to wince in dismay. The "feature" had landed them in the middle of a garbage-collection heap. Data chunks that hadn't been accessed in weeks floated in pools of decaying bits. "Bletch!" was Con's first comment. "And foo and barf!" was his second. The Bookie looked as though he'd just payed off a 555-1 long shot. Luke was polling the garbage for useful items. "What's this?" He dusted off a flat black box with a panel display on one side and "Don't Panic" in large friendly letters on the other. "This can't possibly help us now" he said, tossing it aside. The Bookie was about to lay odds on it when Luke disappeared. He popped up across the pool shouting "This is no feature, it's a bug!" and promptly vanished again. Con and the Princess were close to panic when Luke reapeared. "What happened?" they queried concurrently. "I don't know!" gasped Luke. "The bug just automatically dissolved, as far as I could tell. Maybe it hit a breakpoint." "I don't think so" said Con. "Look how this heap is shrinking. I've got a bad feeling about this..." The princess was the first to catch on. "They've implemented a new compaction algorithm!" she exclaimed. --------------------------------------------------------------------------- Will our heroes evade compaction, or will their memory be re-used? Find out in the next episode. *************************************************************************** Whilst PDP-1 is attempting to free the Milliamp Falcon from the tractor feed, our heroes have rescued Princess LA36, but they are trapped in a rapidly compacting garbage heap... --------------------------------------------------------------------------- Episode n+7 Suddenly, Luke remembered the control channel to the droids. "RS232 - shut down that recursion, quick!" Back in the control room RS232 searched the process table for a LISP interpreter. "Hurry!" said 3CPU. "Hurry, hurry!" added his two other processors. RS232 found the LISP, interrupted it, and altered the stack frames to allow a normal return. "Scramble as many local control paths as you can from there and head back to the ship" Luke ordered. "We've got the Princess!" Meanwhile, PDP-1 was making his way deep into the core of the rm-star, using his ability to manipulate label_t to slip from context to context undetected. Finally he caused a random trap and (through nofault of his own) arrived at the central i-node table. Activity there was always high, but the Sp16 sentries were too secure in their belief that no mere user could interrupt them to notice the bug that PDP-1 introduced. He twiddled the i-node and device numbers on a passing input, carefully maintaining parity, to free the Milliamp Falcon. They would be long gone before the corrupted i-node was diagnosed. He began traversing module structures towards the sub-process where the Falcon had been grounded. During the context switch he felt his priority drop. "That's not nice!" he muttured, then recognised the dark shape before him. "I have waited a long time for this event, PDP-1 Kenobi!" rasped Dec Vadic. "At last we meet again - the circuit is closed." They looped several times, locking Bytesabers. Mesmerized by the spectacle, the few Storm-Flunkies nearby failed to notice Luke, Con, Sixpacca, the Princess and the droids until they'd nearly gained the Falcon's input port. A brief firefight blazed as the six hurled themselves into the ship, but PDP-1 and Vadic seemed too absorbed in their duel to notice. Luke paused at the port, his gaze rivetted on the pair. He gasped - was that phase jitter he saw around the old version? "If my blade finds its mark," Kenobi warned, "you will be resolved to your component bits - but if you slice me down I will only gain computing power." "Your documentation no longer confuses me, old version!" Vadic rasped. "My status is Bus-Master now!". PDP-1 straightened up and halted his Bytesaber. With a sweeping stroke, Vadic's Bytesaber sliced through Kenobi's declaration list. As PDP-1's main body shimmered away Vadic noticed his UID go negative. Odd, he thought, since UID's are unsigned... Vadic whirled to face the Falcon just as the others dragged a stunned Luke into the ship. "We shall meet again...Luke!" he rasped softly to himself, as the ship blasted free. As the Milliamp Falcon hurtled away from the rm-star, the droids were uncharacteristically silent, and Princess LA36 printed comforting messages for Luke. He was inconsolable, hung from the loss of his friend. But strangely, it seemed as though he heard PDP-1's voice in the distance saying softly "Remember, Luke, the Source will always be with you!" --------------------------------------------------------------------------- Probably not to be continued (although you never know!)