Geek:DEC Wars

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Originally released as a series of articles posted to netnews (as it was called) around 1981 and 1982, it is presented here unaltered from its original form...

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      It is a period of system war.  User programs, striking from a
      hidden directory, have won their first victory against the evil
      Administrative Empire.
      During the battle, User spies managed to steal secret source code
      to the Empire's ultimate program: the Are-Em Star, a privileged
      root program with enough power to destroy an entire file
      structure.  Pursued by the Empire's sinister audit trail, Princess
      _LPA0: races aboard her shell script, custodian of the stolen
      listings that could save her people, and restore freedom and games
      to the network...

------------------------------------------------------------------------- 

As we enter the scene, an Administrative Multiplexer is trying to kill a
consulate ship.  Many of their signals have gotten through, and RS232 decides
it's time to fork off a new process before this old ship is destroyed. His
companion, 3CPU, is following him only because he appears to know where he's
going...
 "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 commander of the Administrative Multiplexer was quite pleased with the
attack. 

"Another process just forked, sir. Instructions?" asked the lieutenant.  

"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."

"We can't seem to find the data file anywhere, Lord Vadic."

"What about that forked process?  It could have been holding the channel open,
and just pausing.  If any links exist, I want them removed or made
inaccessable.  Ncheck the entire file system 'til it's found, and nice it -20
if you have to."

Meanwhile, in our wandering process... 

"Are you sure you can ptrace this thing without causing a core dump?" queried
3CPU to RS232.  This thing's been stripped, and I'm in no mood to try and
debug it."  The lone process finishes execution, only to find our friends
dumped on a lonely file system, with the setuid inode stored safely in RS232.
Not knowing what else to do, they wandered around until the jawas grabbed
them.

Enter our hero, Luke Vaxhacker, who is out to get some replacement parts for
his uncle. The jawas wanted to sell him 3CPU, but 3CPU didn't know how to talk
directly to an 11/40 with RSTS, so Luke would still needed some sort of
interface for 3CPU to connect to. 

"How about this little RS232 unit ?" asked 3CPU. "I've dealt 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.

However, RS232 is not the type to stay put once you remove the retaining
screws.  He promptly scurried off into the the deserted disk space.  

"Great!" cried Luke, "Now I've got this little tin box with the only link to
that file off floating in the free disk space. Well, 3CPU, we better go find
him before he gets allocated by someone else."  The two set off, and finaly
traced RS232 to the home of PDP-1 Kenobi, who was busily trying to run an
icheck on the little RS unit.  

"Is this thing yours?  His indirect addresses are all goofed up, and the size
is all wrong.  Leave things like this on the loose, and you'll wind up with
dups everywhere.  However, I think I've got him fixed up."

--------------------------------------------------------------------------- 

Later that evening, after futile attempts to interface RS232 to Kenobi's
Asteroids cartridge, Luke accidentally crossed the small 'droid's CXR and
Initiate Remote Test (must have been all that Coke he'd consumed), and the
screen showed a very distressed person claiming royal lineage making a plea
for help from some General OS/1 Kenobi.

"Darn," mumbled Luke.  "I'll never get this Asteroids game worked out."  PDP-1
seemed to think there was some significance to the message and a possible
threat to Luke's home directory.  If the Administrative Empire was indeed
tracing this 'droid, it was likely they would more than charge for cpu time...

"We must get that 'droid off this file system," he said after some intervals.
They sped off to warn Luke's kin (taking a `relative' path) only to find a
vacant directory...
cat: some directory in the specified path does not exist:
/usr/Tatooine/owen/lars

---------------------------------------------------------------------------

After sifting through the overwritten remaining blocks of Luke's home
directory, Luke and PDP-1 sped away from /owen/lars, across the surface of the
Winchester riding Luke's flying read/write head.  PDP-1 had Luke stop at the
edge of the cylinder overlooking /usr/spool/uucp.

"Unix-to-Unix Copy Program," said PDP-1.  "You will never find a more wretched
hive of bugs and flamers.  We must be cautious."

As our heroes' process entered /usr/spool/news, it was met by a newsgroup of
Administrative protection bits.

"State your UID," commanded their parent process.

"We're running under /usr/guest," said Luke.  "This is our first time on this
system."

"Where did you get these file processes?" the parent process ls -l'ed.  

"We are just in from the remote terminals." replied Luke.

"They could be transferred to your filespace, for the right amount of AU's"
said PDP-1 Kenobi.

"Can I see some temporary privileges, please?"

"Uh..."

"This is not the process you are looking for," piped in PDP-1, using an
obscure bug to momentarily set his effective UID to root.  "We can go about
our business."

"This isn't the process we want.  You are free to go about your business.  MOV
along!"

PDP-1 and Luke made their way through a long and tortuous nodelist
(cwruecmp!decvax!ucbvax!harpo!ihnss!ihnsc!ihnss!ihps3!stolaf) to a dangerous
netnode frequented by hackers, and seldom polled by Administrative
Multiplexers.  As Luke stepped up to the bus, PDP-1 went in search of a likely
file descriptor.  Luke had never seen such a collection of weird and exotic
device drivers.  Long ones, short ones, ones with stacks, EBCDIC converters,
and direct binary interfaces all were drinking data at the bus.

"#@{ *&^%^$$#@ ":>< ," transmitted a particularly unstructured piece of
code.

"He doesn't like you," decoded his coroutine.

"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."

"You'll be reallocated!" concatenated the coroutine.

"This little routine isn't worth the overhead," said PDP-1 Kenobi, overlaying
into Luke's address space.

"@$%&(&^%&$$@$#@$AV^$gfdfRW$#@!!!!!!!!!!!!!!!!!" encoded the first coroutine
as it attempted to overload PDP-1's input overvoltage protection.  With a
unary stroke of his bytesaber, Kenobi unlinked the offensive code.

"I think I've found an I/O device that might suit us."

"The name's Con Solo," said the hacker next to PDP-1.  "I hear you're looking
for some relocation."

"Yes indeed, if it's a fast channel.  We must get off this device."

"Fast channel? The Milliamp Falcon has made the ARPA gate in less than twelve
nodes!  Why, I've even outrun cancelled messages.  It's fast enough for you,
old version."

Our heroes, Luke Vaxhacker and PDP-1 Kenobi made their way to the temporary
file structure.  When he saw the hardware, Luke exclaimed,
"What a piece of junk! That's just a paper tape reader!"

--------------------------------------------------------------------------- 

Luke had grown up on an out of the way terminal cluster whose natives spoke
only BASIC, but even he could recognize an old ASR-33.

"It needs an EIA conversion at least," sniffed 3CPU, who was (as usual) trying
to do several things at once.  Lights flashed in Con Solo's eyes as he whirled
to face the parallel processor.

"I've added a few jumpers.  The Milliamp Falcon can run current loops around
any Administrative TTY fighter.  She's fast enough for you."

"Who's your co-pilot?" asked PDP-1 Kenobi.

"Two Bacco, here, my Bookie."

"Odds aren't good," said the brownish lump beside him, and then fell silent,
or over.  Luke couldn't tell which way was top underneath all those leaves.
Suddenly, RS232 started spacing wildly.  They turned just in time to see a
write cycle coming down the UNIBUS toward them.
"Administrative Bus Signals!" shouted Con Solo.  "Let's boot this pop stand!
Tooie, set clock fast!"  

"Ok, Con," said Luke.  "You said this crate was fast enough.  Get us out of
here!"

"Shut up, kid!  Two Bacco,  prepare to make the jump into system space! I'll
try to keep their buffers full."

As the bookie began to compute the vectors into low core, spurious characters
appeared around the Milliamp Falcon.  

"They're firing!" shouted Luke. "Can't you do something?"

"Making the jump to system space takes time, kid.  One missed cycle and you
could come down right in the middle of a pack of stack frames!"

"Three to five we can go now," said the bookie.  Bright chunks of position
independent code flashed by the cockpit as the Milliamp Falcon jumped through
the kernel page tables.  As the crew breathed a sigh of relief, the bookie
started paying off bets.

"Not bad, for an acoustically coupled network," remarked 3CPU.  "Though there
was a little phase jitter as we changed parity."

--------------------------------------------------------------------------- 

The story thus far:  Luke, PDP-1 and their 'droids RS232 and 3CPU have made
good their escape from the Administrative Bus Signals with the aid of Con Solo
and the bookie, Two Bacco.  The Milliamp Falcon hurtles onward through system
space.  Meanwhile, on a distant page in user space...

Princess _LPA0: was ushered into the conference room, followed closely by Dec
Vadic.  

"Governor Tarchive," she spat, "I should have expected to find you holding
Vadics lead.  I recognized your unique pattern when I was first brought
aboard."  She eyed the 0177545 tatooed on his header coldly.  

"Charming to the last," Tarchive declared menacingly.  "Vadic, have you
retrieved any information?"

"Her resistance to the logic probe is considerable," Vadic rasped. "Perhaps we
would get faster results if we increased the supply voltage..."  

"You've had your chance, Vadic.  Now I would like the princess to witness the
test that will make this workstation fully operational.  Today we enable the -
r beam option, and we've chosen the princess' $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 inode!" Tarchive snapped.

A voice announced over a hidden speaker that they had arrived in /usr.  

"1248," she whispered, "They're on /dev/rm3.  Inode 1248, /mnt/dantooine." She
turned away.

Tarchive sighed with satisfaction.  "There, you see, Lord Vadic?  She can be
reasonable.  Proceed with the operation."

It took several clock ticks for the words to penetrate.  "What!" _LPA0:
gasped.

"/dev/rm3 is not a mounted filesystem," Tarchive explained.  "We require a
more visible subject to demonstrate the power of the Are-Em Star workstation.
We will mount an attack on /mnt/dantooine as soon as possible."

As the princess watched, Tarchive reached over and typed "ls" on a nearby
terminal.  There was a brief pause, there being only one processor on board,
and the viewscreen showed, ".: not found."  The princess suddenly double-
spaced and went off-line.

--------------------------------------------------------------------------- 

The Milliamp Falcon hurtles on through system space...

Con Solo finished checking the various control and status registers, finally
convinced himself that they had lost the Bus Signals as they passed the
terminator.  As he returned from the I/O page, he smelled smoke. Solo wasn't
concerned -- the Bookie always got a little hot under the collar when he was
losing at chess.  In fact, RS232 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 weapon of the Red-eye Night.  It is used to trim offensive
lines of code.  Excess handwaving won't get you anywhere. Listen for the
Carrier."

Luke turned back to the drone, which was humming quietly in the air next to
him.  This time Luke's actions complemented the drone's attacks perfectly.  

Con Solo, being an unimaginative hacker, was not impressed.
"Forget this bit-slicing stuff.  Give me a good ROM blaster any day."

"~~j~~hhji~~," said Kenobi, with no clear inflection.  He fell silent for a
few seconds, and reasserted his control.

"What happened?" asked Luke.

"Strange," said PDP-1.  "I felt a momentary glitch in the Carrier.  It's
equalized now."

"We're coming up on user space," called Solo from the CSR.  As they cruised
safely through stack frames, the emerged in the new context only to be
bombarded by freeblocks.

"What the..." gasped Solo.  

The screen showed clearly: /usr/alderaan: not found

"It's the right inode, but it's been cleared!  Twoie, where's the nearest
file?"

"3 to 5 there's one..." the Bookie started to say, but was interrupted by a
bright flash off to the left.

"Administrative TTY fighters!" shouted Solo.  "A whole DZ of them!  Where are
they coming from?"

"Can't be far from the host system," said Kenobi.  "They all have direct EIA
connections."

As Solo began to give chase, the ship lurched suddenly.  Luke noticed the link
count was at 3 and climbing rapidly.

"This is no regular file," murmured Kenobi.  "Look at the ODS directory
structure ahead!  They seem to have us in a tractor feed."

"There's no way we'll unlink in time," said Solo.  "We're going in."
--------------------------------------------------------------------------- 

When we last left Luke, the Milliamp Falcon was being pulled down to the open
collector of the Administrative Are-Em Star Workstation.  Dec Vadic surveys
the relic as Administrative Flunkies search for passengers...  

"LS scan shows no one aboard, sir," was the report.  Vadic was unconvinced.
"Send a fully equipped Ncheck squad on board," he said.  "I want every inode
checked out."  He turned around (secondary channel) and stalked off.  

On board the Milliamp Falcon, .Luke was puzzled.  "They just walked in, looked
around and walked off," he said.  "Why didn't they see us?"

.Con smiled.  "An old munchkin trick," he explained.  "See that period in
front of your name?"

.Luke spun around, just in time to see the decimal point.  "Where'd that come
from?" he asked.

"Spare decimal points lying around from the last time I fixed the floating
point accelerator," said .Con.  "Handy for smuggling blocks accross file
system boundaries, but I never thought I'd have to use them on myself. They
aren't going to be fooled for long, though.  We'd better figure a way outa
here."

---------------------------------------------------------------------------

"Hold on," said Con.  "It says we have `new mail.'  Is that an error?"  

"%SYS-I-NORMAL, Normal, successful completion," said PDP-1.  "Doesn't look
like it.  I've found the inode for the Milliamp Falcon.  It's locked in kernel
data space.  I'll have to slip in and patch the reference count, alone."  He
disappeared through a nearby entry point.

Meanwhile, RS232 found a serial port and logged in.  His bell started ringing
loudly.  

"He keeps saying, `She's on line, she's on line'," said 3CPU.  "I believe he
means Princess _LPA0:.  She's being held on one of the privileged levels."

---------------------------------------------------------------------------

"Good day, eh?" said the first guard.

"How's it goin', eh?" said the other.  "Like, what's that, eh?"

"Process transfer from block 1138, dev 10/9," said Con.

"Take off, it is not," said the first guard.  "Nobody told US about it, and
we're not morons, eh?"

At this point (.), the Bookie started raving wildly, Con shouted "Look out,
he's loose!" and they all started blasting ROMs left and right.  The guards
started to catch on and were about to issue a general wakeup when the ROM
blasters were turned on them.

"Quickly, now," said Con.  "What buffer is she in?  It's not going to take
long for these..."

The intercom receiver interrupted him, so he took out its firmware with a
short blast.

"guys to figure out something is goin' on," he continued.

--------------------------------------------------------------------------- 

Ok, like, remember we left our heroes in the detention priority level?  Well,
they're still there...

Luke quickly located the interface card and followed the cables to a sound-
proof enclosure.  He lifted the lid and peered at the mechanism inside.  

"Aren't you a little slow for ECL?" printed princess _LPA0:.

"Wha?  Oh, the Docksiders," stammered Luke.  He took off his shoes (for
industry) and explained, "I've come relocate you.  I'm Luke Vaxhacker."  

Suddenly, forms started bursting around them.  

"They've blocked the queue!" shouted Solo.  "There's only one return from this
stack!"

"OVER HERE!" printed _LPA0: with overstrikes.  "THROUGH THIS LOOPHOLE!" Luke
and the princess disappeared into a nearby feature.

"Gritch, gritch," mumbled Two Bacco, obviously reluctant to trust an
Administrative oversight.

"I don't care how crufty it is!" shouted Con, pushing the Bookie toward the
crock.  "DPB yourself in there now!"

With one last blast that reprogrammed two flunkies, Con joined them. The
"feature" landed them right in the middle of the garbage collection data.
Pieces of data that hadn't been used in weeks floated past in a pool of
decaying bits.

"Bletch!" was Con's first comment.  "Bletch, bletch," was his second. The
Bookie looked as if he'd just paid a long shot, and the odds in this situation
weren't much better.

Luke was polling the garbage when he stumbled upon a book with the words
"Don't Panic" inscribed in large, friendly letters on the cover.  "This can't
possibly help us now," he said as he tossed the book away.

The Bookie was about to lay odds on it when Luke suddenly disappeared. He
popped up accross the pool, shouting, "This is no feature! It's a bug!" and
promptly vanished again.

Con and the princess were about to panic() when Luke reappeared.  

"What happened?" they asked in parallel.

"I don't know," gasped Luke.  "The bug just dissolved automagically. Maybe it
hit a breakpoint..."

"I don't think so," said Con.  "Look how the pool is shrinking.  I've got a
bad feeling about this..."

The princess was the first to realize what was going on.  "They've implemented
a new compaction algorithm!" she exclaimed.

Luke remembered the pipe he had open to 3CPU.  "Shut down garbage collection
on recursion level 5!" he shouted.

Back in the control room, RS232 searched the process table for the lisp
interpreter.  "Hurry," sent 3CPU.  "Hurry, hurry," added his other two
processors.  RS232 found the interpreter, interrupted it, and altered the
stack frame they'd fallen into to allow a normal return.

--------------------------------------------------------------------------- 

Meanwhile, PDP-1 made his way deep into the core of the Workstation, slipping
from context to context, undetected through his manipulation of label_t.
Finally, causing a random trap (through nofault of his own) he arrived at the
inode table.  Activity there was always high, but the Spl6 sentries were too
secure in their knowledge that no user could interrupt them to notice the bug
that PDP-1 carefully introduced.  On a passing iput, he adjusted the device
and inode numbers, maintaining parity, to free the Milliamp Falcon.  They
would be long gone before the locked inode was diagnosed...

Unobserved, he began traversing user structures to find the process where the
Milliamp Falcon was grounded.  Finding it and switching context, he discovered
his priority weakened suddenly.  "That's not very nice," was all he could say
before the cause of the obstruction became clear.  

"I have been pausing a long time, PDP-1 Kenobi," rasped Dec Vadic.  "We meet
again at last.  The circuit has been completed."

They looped several times, locking byte sabers.  Bit by bit, PDP-1 appeared to
weaken.  The fight had come into the address space of the Milliamp Falcon, and
provided the .di (diversion?) that allowed Luke and the others to reassert
control.  Luke paused to watch the conflict.

"If my blade finds its mark," warned Kenobi, "you will be reduced to so many
bits.  But if you slice me down, I will only gain computing power."  

"Your documentation no longer confuses me, old version," growled Vadic. "my
Role MASTER now."

With one stroke, Vadic sliced Kenobi's last word.  Unfortunately, the word was
still in Kenobi's throat.  The word fell clean in two, but Kenobi was nowhere
to be found.  Vadic noticed his victim's uid go negative, just before he
disappeared.  Odd, he thought, since uids were unsigned...  

Luke witnessed all this, and had to be dragged into the Milliamp Falcon. Con
Solo and Two Bacco maneuvered the Milliamp Falcon out of the process, onto the
bus and made straight for system space.  3CPU and RS232 were idle, for once.
Princess _LPA0: tried to print comforting things for him, but Luke was still
hung from the loss of his friend.  Then, seemingly from nowhere, he thought he
heard PDP-1's voice say,

"May the carrier be with you."

--------------------------------------------------------------------------

AND I BET YOU CAN'T WAIT FOR THE NEXT PART -

                  "DECWARS II - THE OPERATORS STRIKE BACK"

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