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Hidden Codes in Printers Cracked

Posted by CmdrTaco on Tue Oct 18, 2005 07:50 AM
from the big-brother-pwnz-you dept.
r84x writes "A research team led by the Electronic Frontier Foundation (EFF) recently broke the code behind tiny tracking dots that some color laser printers secretly hide in every document. The U.S. Secret Service admitted that the tracking information is part of a deal struck with selected color laser printer manufacturers, ostensibly to identify counterfeiters. However, the nature of the private information encoded in each document was not previously known. "We've found that the dots from at least one line of printers encode the date and time your document was printed, as well as the serial number of the printer," said EFF Staff Technologist Seth David Schoen."
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[+] Hardware: Secret Printer ID Codes May Be Illegal In the EU 229 comments
I Don't Believe in Imaginary Property writes "In response to a query from a member of the EU Parliament, an EU commissioner issued an official statement (.DOC) saying that, while they do not violate any laws, secret printer tracking dot codes may violate the human right to privacy guaranteed by the EU's Convention of Human Rights and Fundamental Freedoms. If you don't remember what these are, Slashdot has discussed the issue before. In short, most color printers print small yellow dots on every sheet in a code that identifies the printer and, potentially, its owner. The EFF is running an awareness campaign, and a couple of years back made a start on deciphering the yellow dot code."
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  • by suso (153703) * on Tuesday October 18 2005, @07:51AM (#13816210) Homepage Journal
    Its a good thing that I can't print [suso.org]. [warning: experimental music made from printer noises]
  • by OctoberSky (888619) on Tuesday October 18 2005, @07:53AM (#13816226)
    Anyone have a printer friendly version? On second thought.... nevermind. //Tin foil hat on
    • by Smidge204 (605297) on Tuesday October 18 2005, @08:18AM (#13816406)
      Forget the tinfoil hats! Everything I print from now on will be on foil-backed paper!

      =Smidge=
        • by SB5 (165464) <freebirdpat@@@hotmail...com> on Tuesday October 18 2005, @08:47AM (#13816633)
          Hell, it's not like anyone actually cares what you print unless you're doing something illegal that would warrent them spending a lot of time and money to try and find you.


          That is true in an uncorrupted system. The question remains what would happen if someone did use their power like J. Edgar Hoover did, and others in history that have got away with abuse of power in such a manner.

          And there is the case of just because something is illegal, that doesn't mean that something is a wrong thing to do.
          • by Analogy Man (601298) on Tuesday October 18 2005, @10:07AM (#13817364)
            Where do we stop using intrusive technologies.

            • Felonious use of technology (e.g. counterfieter)
            • Legal use by felon (e.g. mail from murderer)
            • Illegal use as civil disobediance (e.g. printing document that is improperly classified secret for political reasons)
            • Constitutionally protected but anti-establishment use (e.g. hand distribution of fliers of "Top 10 Reasons to Impeach Congressman Blowhard")

            The "if you have nothing to hide" apologists for elimination of freedoms is a slippery slope to totalitarianism. Orwell would snicker!

              • by quarkscat (697644) on Tuesday October 18 2005, @03:13PM (#13820255)
                "There seem to be a lot of people who confuse *freedom* with *freedom to do antisocial stuff and remain anonymous*."

                Ahh. Spoken like a true facist. You are taking the right of free expression in a democratic society and chaining it to the dungeon wall with the use of another as yet to be defined term, "antisocial stuff". Would that be "antisocial" as defined by the ruling political party, whichever religious sect is currently in vogue, or perhaps as determined by a public poll?

                "Free speech is not free *anonymous* speech."

                What a crock! One of the basic rights any citizen of a democracy has is the right to vote, PRIVATELY. No other person, group of persons, or government entity is granted the right to know how an individual votes -- without such privacy protections the entire foundation of democracy is open to the social, political or financial pressure to vote a particular way.

                And only in a democracy falling to the continued pressures of fascist stateism would the government redefine the ephemeral and undefined term "free press" only as persons engaged in journalistic activities employed by corporate media moguls.

                I would suggest that you spend a few years in the "new and improved" fascist USSR, being run by an ex-KGB general, and experience the fruits of your specious argument firsthand.
        • by nolife (233813) on Tuesday October 18 2005, @08:55AM (#13816711) Homepage Journal
          Hell, it's not like anyone actually cares what you print unless you're doing something illegal that would warrent them spending a lot of time and money to try and find you.
          The people that do not want their houses randomly searched must be hiding something, after all, why would they not want searched? I know, point taken to the extreme but where do you draw the line?
            • by LearnToSpell (694184) on Tuesday October 18 2005, @10:12AM (#13817418) Homepage
              Not if they search your house when you're not home! No inconvenience for anyone! In fact, you might not even know they've been there. Everybody wins.
              • by tha_mink (518151) on Tuesday October 18 2005, @12:03PM (#13818363)
                Actually, it could cause a lot of inconvenience. Suppose a dirty printer head leads to the code being misprinted. A printed document, with the incorrect information, is involved in a murder or child rape investigation. Suddenly you become a suspect, even though you had no involvement, and the problem was with the printer. You could potentially be stuck defending yourself against baseless charges. That can take a massive financial toll, not to mention ruin your reputation. Hardly without inconvenience, indeed.

                Or even worse...you buy and register a printer, and six months later sell it to some registered sex offender. It's a cash deal with no records. Six months and one day later that printer is used for some kidnapping randsom note or some shit. Who would believe it wasn't you? Your mom?
        • Hell, it's not like anyone actually cares what you print unless you're doing something illegal that would warrent them spending a lot of time and money to try and find you.
          Don't ever think it won't happen to you for no reason. If you do, one day, I'll guarantee you'll be for a very rude awakening.

          Just wait until you get your ass hauled-in by an overzealous cop while you were doing something perfectly innocent or legal (like photographing old buses at a busy intersection - I know, it happenned to me. Two hours of vacation down the drain because some shit-brained bitch thought I was a terrorist - no, don't ask what happenned in her sorry neurons to think that).

          Cops think they are above normal civilians and do not hesitate to abuse their powers. For them, making a lowly civilian life hell is just what swatting a fly for you.

          The easier it is to abuse their power (like finding out where one photocopy was made), the more likely they will do it.

          Now that the EFF has published the "secret" code, everyone can do it, including that jealous spouse, screwey boss or suspicious business associate.).

          Cops think they are above normal civilians and do not hesitate to abuse their powers. For them, making a lowly civilian life hell is just what swatting a fly for you.

          The easier it is to abuse their power (like finding out where one photocopy was made), the more likely they will do it.

          Now that the EFF has published the "secret" code, everyone can do it, including that jealous spouse, screwey boss or suspicious business associate.

            • by pla (258480) on Tuesday October 18 2005, @11:58AM (#13818312) Journal
              They deal with people who are abusing their kids;

              ...Or take that job upon themselves with creative use of the ever-popular "resisting arrest" claim. Clumsy kids, always going around breaking their own ribs while locked alone in a jail cell.


              or acting indignent because they got pulled over for speeding;

              Or driving while black. Or a personal favorite, driving on the wrong side of the road - On a lineless back road barely wide enough for a single car (the sort where you literally stop and one car pulls totally off the road if you meet another car coming the opposite way).


              or drunk and screaming obscenities in public places;

              Or ordered to step outside a bar, given a sobriety test, and charged with public drunkenness.


              or involved in horrible accidents and shootings.

              You mean like when a cop panics over a 2YO kid with a cap gun, and ventilates him? Or when they zealously chase a gas station drive-off at 110mph leading to three deaths over $30 in fuel?


              It's even more unlikely that the government is going to use this against you, unless you do something to draw the attention of say, the FBI.

              You mean like anonymously distributing a (legal) pamphlet critical of the wrong politician, who wants revenge and has convenient connections?



              I appreciate what police do. They keep a bunch of unruly domesticated primates from killing one another.

              But don't glorify them - They chose that job because they get to act the most like unruly domesticated primates, and justify it as part of the job. Politicians chose their job because they like power (or money, or both). WE all need to do our part to keep the police, and the government in general, in check.
  • Before... (Score:5, Insightful)

    by trevordactyl (908770) on Tuesday October 18 2005, @07:53AM (#13816227)
    Before anyone has a conniption, consider this: do you really think that "they" have a database they could reference to find out what printer serial number goes to what citizen? I don't. I know they could, but I choose to believe (most likely for good reason) that they don't.

    Just realize that 99.9% of the world doesn't give a shit about anything you do, and all that paranoia just slips away. That's what I did.
    • Re:Before... (Score:5, Informative)

      by Anonymous Coward on Tuesday October 18 2005, @07:58AM (#13816251)
      do you really think that "they" have a database they could reference to find out what printer serial number goes to what citizen?

      Most laser printers are rather expensive items. If you paid with a credit card, then yes, they have it in a database. (All stores record the serial number of high-ticket items they sell. I've actually gotten recall notices this way, so I know the store shares it with the manufactorer.) Even if you paid in cash, if you filled in the warranty card, they have it. Got a mail-in rebate? On file. Ever had to have it serviced? You're on file.
      • Re:Before... (Score:4, Insightful)

        by Itchy Rich (818896) on Tuesday October 18 2005, @08:33AM (#13816512)

        If you paid with a credit card, then yes, they have it in a database.

        The retailer or manufacturer may have it in a database, but whatever shadowy organisations the parent was alluding to probably doesn't. Government agencies have enough trouble keeping track of where people live without having to track their posessions too.

        • Re:Before... (Score:5, Insightful)

          by panthro (552708) <mavrinacNO@SPAMgmail.com> on Tuesday October 18 2005, @08:53AM (#13816683) Homepage
          The Shadowy Organization probably doesn't have all that information on file directly, but clearly the idea behind setting up this "deal" with the printer manufacturers is that they can obtain the information from them when they need it (say, when they find a fake twenty with the dot pattern embedded).

          Who's to say what it takes for them to obtain this information and how they use it? I'm personally not satisfied to just think "they'll only obtain it when they need it, and they will only use it for a Good Cause". It's not paranoia, it's like Murphy's law: if it can be abused, it probably will be.
        • Re:Before... (Score:5, Insightful)

          by Hans Lehmann (571625) on Tuesday October 18 2005, @08:58AM (#13816729)
          The CIA/FBI doesn't need to keep the information in a database, they have the manufacturers & retailers to do that for them. If they find a printed paper that's of "interest", they contact the manufacturer of the printer. The manufacturer knows which retailer the printer was sold to. The retailer, not wanting to question on their patriotism, rolls over & hands them your credit card information. Presto, you've vanished to behind barbed wire on some Carribean island.
        • Re:Before... (Score:5, Interesting)

          by xappax (876447) on Tuesday October 18 2005, @09:08AM (#13816831)
          God bless the PATRIOT Act, which among many other things, grants law enforcement agencies broad privileges to private corporate information in the name of investigating "terrorism". Fact is, neither the FBI nor Xerox would have to (or in Xerox's case, be allowed to) tell you that they had shared their serial number database with the government.

          I hear the argument over and over again that "just because they're allowed to, the government doesn't have time to spy on little old you, so quit being paranoid". This is true, and the government realizes it, which is why they are striving for "Total Information Awareness". The idea is that all the information the feds could ever desire is already collected in outrageous detail by private organizations like the phone company, ISPs, bookstores, etc. - so why not just pass laws granting the Feds unrestricted, secret access to this info? That way, the government doesn't have to have been spying on you your whole life. The moment you get caught up in some "suspicious" incident like looking around too much on the subway or criticizing the American government while in an American airport, your whole history is at the government's fingertips (including, now, what documents you printed!), and believe me, they'll find reasons for suspicion.

          God bless the PATRIOT Act, my friend.
    • Re:Before... (Score:5, Insightful)

      by Alchemar (720449) on Tuesday October 18 2005, @08:01AM (#13816275)
      What do you think all the registration cards that are "required" for warrenty are about. It is utterly amazing how much junk they store on individuals in the name of marketing. I will agree that no one will care about most people, but not caring and not having the information in a database are two different things. I have a very unique name derived from a misspelling on a birth certificate. The only two people in the world with my name is me and my father, but I still pull up over 500 hits if I enter it in google. Most of them some kind of goverment or school entery. No one cares about me or my father now, but the information is still there if that ever changes.
    • Re:Before... (Score:5, Interesting)

      by Anonymous Coward on Tuesday October 18 2005, @08:02AM (#13816276)
      do you really think that "they" have a database they could reference to find out what printer serial number goes to what citizen?

      Yes, they must, otherwise this tracking information is useless, right? They can't be that dumb. And most high-end color printers are sold to businesses and often have service contracts. It's not that hard. How many people buy a printer for cash?

      And many networked printers "phone home" to the manufacturer via email or web. My Xerox phaser 7750 (great printer, btw) tries to send an email every month to Xerox. They're blocked now.

      Just realize that 99.9% of the world doesn't give a shit about anything you do, and all that paranoia just slips away.

      I know that. But I prefer that my printer doesn't track what I print.
      • Re:Before... (Score:4, Insightful)

        by WeeLad (588414) on Tuesday October 18 2005, @08:46AM (#13816629) Journal
        Yes, they must, otherwise this tracking information is useless, right?

        I don't know that the lack of a database would make the information useless. It may work like running ballistics tests on a shell casing found at a crime scene and matching it to a weapon seized from a suspect.

        Even if there ability to find a suspect is limited, they may have the ability to prove, within a court of law, that a document came from the printer in your basement.

    • by sisina (849900) on Tuesday October 18 2005, @08:03AM (#13816288)
      Holy crap! 600,000 people are watching every move I make? Where's my Xanax??
    • Re:Before... (Score:5, Interesting)

      by aug24 (38229) on Tuesday October 18 2005, @08:14AM (#13816378) Homepage
      Yeah, I reckon they do. I work implementing such systems. Read on...

      Modern asset tracking systems use the serial number of each big-ticket item to track it (if it is serialised - most expensive kit is). The asset, whatever it is, is tracked from entry to the system through to exit - with an EPOS transaction being recorded against it as it leaves if sold.

      It is pretty damn easy for a database coder to write a bit of SQL to say 'give me the credit card number that bought this item'. I could do it in minutes.

      Provided the Feds wanted to track a given machine, and it had been bought with plastic, there's no reason they shouldn't be able to find that info very easily, given the cooperation of the vendors. Your last para relies on you not being someone the Feds are interested in - and that relies on you assuming they won't be interested in people who haven't broken the law. I hope you are right, but recent events suggest otherwise to me...

      Justin.
    • Re:Before... (Score:5, Insightful)

      by rbochan (827946) on Tuesday October 18 2005, @08:22AM (#13816434) Homepage
      Yep, and Americans in the 1930's and 1940's didn't think the cute guy/girl they dated for a couple of months in college were any big deal. They didn't think writing a book report for a class was any big deal.

      Then along came Senator Joseph McCarthy...

    • Re:Before... (Score:5, Insightful)

      by DjReagan (143826) on Tuesday October 18 2005, @09:35AM (#13817080)
      "Just realize that 99.9% of the world doesn't give a shit about anything you do, and all that paranoia just slips away"

      Oh, so there's only 0.1% of the world who is interested in what I'm doing?

      I'm glad it works out for you, but 6 million people snooping around in my private life doesn't make my paranoia go away.
      • Re:Before... (Score:5, Interesting)

        by Anonymous Coward on Tuesday October 18 2005, @08:09AM (#13816343)
        I don't know about the USA, but in the UK the only barcode that gets scanned is the 13-digit EAN product code which does not contain any kind of unique serial number.

        Buy a printer and fail to send the warranty card in and there is no entry in any list.

        The reason they have this stuff is so that they can match the printer to the document in the courtroom after they catch you. It's not a tracking system.
        • Re:Er, huh? (Score:4, Informative)

          by sphealey (2855) on Tuesday October 18 2005, @08:29AM (#13816485)
          Do you know anything baout barcodes? Barcodes do not have serial numbers encoded on them. Every printer of the same brand and model has the same barcode. Any other system would increase the cost of printing boxes tenfold.
          Every one of the 5,000 or so pieces of computer equipment I have unpacked over the last 10 years has had the serial number barcoded on the outside of the shipping carton.

          And yes, stores can be required to scan those S/Ns if the feds so desire, and it can be made to stick. Bank tellers don't get paid all that much more than Best Buy clerks, but the threat of 20 years in the federal pen gives them a bit of incentive to follow the money-laundering reporting procedures. Heck, I heard a discussion between two entry-level postal clerks the other day about how much fun they had spotting drug dealers and reporting them.

          sPh

            • Re:Er, huh? (Score:5, Informative)

              by Teilo (91279) on Tuesday October 18 2005, @10:26AM (#13817541) Homepage
              Quite frankly, you have no idea what you are talking about. I work in high-end color, and all of our toner devices have this encoding technology. I have talked to plenty of people in the industry, who sell these machines. They are required, by law, to record the serial number and purchaser of every such device. Furthermore, they are required by law to record the sale of any electronic part used in these devices, and yes, all the boards are individually keyed to the serial number of the device. Swap boards with another device, and the machine stops functioning.

              This is also true of the mid-range color laser printers you purchase at your local Best Buy or Micro Center. In fact, if you open your eyes at the checkout and actually pay attention, you would notice that after they scan the bar-code, their register prompts them to either scan the serial number bar-code, or hand-key in the serial number. Now, they may not be required to record your name and address, but they most certainly can trace it back to your credit card.

              The whole point of this is to catch counterfeiters. It's useless to know the serial-number of a device if you don't know where it was sold.
            • by CharlieHedlin (102121) on Tuesday October 18 2005, @08:58AM (#13816745)
              If I buy a $50 DVD player at wallmart, the register prompts the clerk to scan the serial number barcode. Last year I had a few clerks look very confused. One said "I don't want to type that" and I pointed out that they could use their barcode scanner.

              If they track it, everyone does. Everything I mail order has the barcode scanned and printed on the packing slip.

              Get a clue.
  • more links (Score:5, Informative)

    by morcheeba (260908) * on Tuesday October 18 2005, @07:54AM (#13816233) Journal
    For those interested in a quick summary, the docucolor example [eff.org] is the best place to look. (it has pictures!)

    More information can be found on the EFF's printer-privacy webpage. [eff.org]

    Also interesting is Andrew Bunnie's flat bed page scanner mod [bunniestudios.com] to use blue light instead of white. This made the yellow tracking dots easier to see, and the whole page could be seen at once to determine the pattern they made.
    • by Animaether (411575) on Tuesday October 18 2005, @08:06AM (#13816313) Journal
      You'd think it would be easier to...

      A1. scan as normal
      A2. separate the channels into CMYK in Photoshop/whathaveyou
      A3. inspect the Yellow channel.

      B1. scan as normal
      B2. separate the channels into RGB in GIMP/whathaveyou
      B3. do a difference matte between the channels
      B4. inspect the result

      C1. replace the yellow toner cartridge with a black one
      C2a. stock the other holders with empty cartridges
      C2b. or if that causes a printer error/warning, block the cartridges' output
      C3. print

      D1. get a sheet of blue filter plastic
      D2. scan through that

      But I guess the array of blue LEDs with soldering involved is a lot more geeky :)
    • by meringuoid (568297) on Tuesday October 18 2005, @08:08AM (#13816327)
      Also interesting is Andrew Bunnie's flat bed page scanner mod to use blue light instead of white. This made the yellow tracking dots easier to see, and the whole page could be seen at once to determine the pattern they made.

      Right. So now, in order to ensure that we remain safe from terrorists, paedophiles, and liberals, we need to compel scanner manufacturers to make sure their products will refuse to show the secret codes we already compelled the printer manufacturers to install.

      Don't worry, citizen. We have it all under control.

  • by GroeFaZ (850443) on Tuesday October 18 2005, @07:58AM (#13816256)
    "If you can read this, you are about to be busted"
  • by Anonymous Coward on Tuesday October 18 2005, @07:58AM (#13816259)
    I bet most people's printers will print "Jan-01 1980 12:00" in little blinking dots.
  • Conspiracy math (Score:5, Insightful)

    by zappepcs (820751) on Tuesday October 18 2005, @07:59AM (#13816264) Journal
    I love conspiracy math: Lets see, conservative estimate of 400 million printers in North America alone, and no method of tracking serial number to location or owner past the original purchase, assuming cash was not used. So, hmmmm a data base with 400 million records, tied to dubious information... yeah, that's useful, but on second thought, it would allow police to figure out if the printer that counterfit documents were created with was in North America or Europe... that would be helpful, but not really worth putting on the tin foil hats.

    Anyway, so the government requires each printer manufacturer to maintain a database of all printers sold, so that if needed, they can subpeona the records? No wonder printer ink costs so much :)

    I'm thinking that this would only go so far, and not be much more useful than a database of gun rifling marks?
    • Re:Conspiracy math (Score:5, Informative)

      by photon317 (208409) on Tuesday October 18 2005, @08:18AM (#13816405)

      Even if all the database can tell them reliably is that HP ColorLaserJet Model 55 Serial Number 89928798734 was distributed to a certain Best Buy store, that goes a long way. When the Secret Service finds counterfeit bills, they know from the serial what store it was originally purchased in. Chances are it didn't move far, and chances are that Best Buy's records can lead to a very short list of potential buyers. Even if it was resold by one of them, the investigation becomes fairly trivial at that point.

      But perhaps more importantly, even if you can't use it (embedded serial numbers in documents) as a primary method of tracking down the counterfeiter, you can certainly use it as court evidence once you do catch them by other means. It's pretty damning evidence if they can show that they seized a printer with serial number 89928798734 at your home address, and they can also show conterfiet currency or documents with the same serial number embedded that showed up elsewhere.
    • Quit being clueless. (Score:5, Interesting)

      by cnelzie (451984) on Tuesday October 18 2005, @08:26AM (#13816463) Homepage
      Let's assume you purchase your color laser printer with cash.

          Let's assume you take that home and hook it up to your Windows XP Home Edition printer.

          Now, that printer is installed and it requests you "Register" the printer. You decline to do so.

          During the normal course of use, a little dialog box pops up stating that there is an update to download from your color laser printer manufacturer's website and the printer application will be more then happy to do so.

          How does your application know that it needs to be updated? Well, it checked with a central server.

          If that application checks with a central server, would it be difficult to imagine that the central server would be able to obtain the following?

          IP Address, Printer Serial number, timestamp of communication.

          With just the timestamp and the IP Address your PC used to communicate with the central server, you can be easily traced. It's easier if you are on broadband, slightly more difficult if you are on a service like AOL or MSN.

          I am not being a tinfoil hat wearer here. I am just pointing out that it is actually easier to track down a user of a particular printer then you believe it to be.

          The only way to be more anonymous with such a cash paid color laser printer purchase would be to never connect it to a PC that has Internet Access.
  • by doublem (118724) on Tuesday October 18 2005, @08:03AM (#13816290) Homepage Journal
    In Soviet Russia, anyone who owned a typewriter was required to send a sample page to the government.

    The theory of course being that they would use it to try and track down any subversive content.

    And now the US government has made it quick, easy and automated to do the same.

    I want to know who the bastards are that are adding this technology to their printers so I can avoid them like the plague.

    Yes, I know I could just not send in the registration card, but what if the government decided to crack down on those who critisize the war? Suddenly when they confiscate my printer, they can find out if any of the documents they've declared subversive came from my printer.

    This is too Big Brother for my tastes.
  • by Junior J. Junior III (192702) on Tuesday October 18 2005, @08:07AM (#13816319) Homepage
    Just send in the little round yellow guy to eat some of the dots and confuse the feds. No more paranoia!
  • by Albanach (527650) on Tuesday October 18 2005, @08:07AM (#13816325) Homepage
    How much of this is encoded in the printer driver? In other words, are OSS drivers partially immune?

    I can only imagine the time and date are passed from the host PC - most printers don't know what time/date it is - at least on those I jsut glanced at I can't set it myself. Of course the network attached ones could have an NTP client but that'd be easily blocked at the firewall.

    At least if you can make every printout say it happened three decades ago you don't need to worry about proving you were not in the office at the time the printout was made.

    • by molo (94384) on Tuesday October 18 2005, @08:24AM (#13816447) Journal
      This is for color lasers. The EFF tests to generate sample pages were done with postscript that gets fed directly to the printers. You might be able to hack the firmware, the encoded data gets added by either the postscript rasterizer or the actual bitmapped layout engine.

      My bet is on the rasterizer.

      -molo
    • by ebuck (585470) on Tuesday October 18 2005, @08:36AM (#13816544)
      Past disccussions have indicated that this information is programmed into the printer control circuits themselves, no software is required or even aware of the "extra" dots.

      If that is true, then no amount of dirver manipulation will help, with the possible exception of a driver that "adds" extra dots to make the message meaningless. In theory, you could add extra dots, but in practice it would be ineffective unless you could gurantee perfect alignment (or the extra dots would be easy to filter out). Since some dots would come from software, and others come from hardware control programs, it's not a simple task to gurantee alignment.
    • by morcheeba (260908) * on Tuesday October 18 2005, @08:47AM (#13816635) Journal
      I forgot to link to Bunnie's printer disassembly [bunniestudios.com] [via [hackaday.com]]

      The basic conclusion is that many of the watermarked printers share a Canon print engine -- he suspects it is this engine that is doing the watermarking. The US Government just had to convince the critical-equipment supplier to add the tracking - not all the printer companies. He also notes that the Tek Phaser printers don't have this because they were developed before the Canon engine. (Oh, how I longed for a phaser back in the day!)
  • by G4from128k (686170) on Tuesday October 18 2005, @08:11AM (#13816353)
    Once the code is cracked, anyone can add a pattern of yellow dots that say anything. Assuming someone can tweeze the overlapping codes, they would discover that the document was printed 10/10/05 by printer 2721272 or 5/8/05 by printer 8798798 or 11/2/05 by printer 9813982, etc. If one can get the alignment right, one could even fill-in the printer's native dot pattern so that all pages are printed on FF/FF/FF by printer FFFFFFF.
  • by maetenloch (181291) on Tuesday October 18 2005, @08:22AM (#13816439)
    here [bunniestudios.com] a guy opened up his HP printer and looked at the chips involved. It appears that all the printers with hidden codes use the Canon print engine board. Changing the pattern might be as easy as reflashing an eeprom.
    • by RubberDogBone (851604) * on Tuesday October 18 2005, @09:50AM (#13817207)
      Speaking as a trained Xerox Docu* operator who can recite his DEEZEROCEE serials in his sleep.....

      The DocuColor printers in question are very high end printer/copiers that are installed and maintained by trained technicians known by Xerox as Customer Service Engineers or CSEs. When it breaks or needs parts, you call your CSE. Think "on-site support" but on steroids. You pay a ton for this.

      The system clock is set by the installer CSE and possibly updated as needed on subsequent service calls, and there are MANY of those as DocuColors require frequent maintenance and upkeep. It is not uncommon to have service once a week for some models. Or worse. They can be touchy beasts. The machines, I mean. The CSEs can be your pal or your worst nightmare. I like the ones my bosses hate. Go fig.

      So what is the clock for? Among other things, time stamps are used by the printshop for tracking when every single print was made including which operator made it. So no more late night "free copies" for your pals. Xerox also uses the logs for all sorts of legit reasons. Nothing evil there.

      So what about resetting the clock? First you'd have to get the machine open. This is not like a computer with handy access panels and common PCBs, er, that's PWBs in Xerox-speak. You'd have to know the machine inside-out, have the tools and the skill to take it apart (God help you), and hope that the battery is resettable rather that buried inside a chip. Xerox is very, very aware of people trying to cheat the machine meters to make free copies so stuff like counters and clocks are already armored and protected from prying hands.

      Assuming you managed to do all those things and got the machine back together, then it has to be recalibrated because taking it apart will have wrecked the system setup. So you have to call your CSE, who resets the clock straight away, probably by pushing the keys with the bones he removed from your hands for messing with his machine. If you're still alive at this point, you are right back where you started!

      Side notes: the vast majority of DocuColors are leased out by Xerox rather than sold, so the machine is normally Xerox property from assembly to reman to reman to reman to junkyard. Why? Some of them can cost half a million and up for new, less for used, but either way these are not something people "buy" when they can simply lease. GE Credit is happy to finance the leases and end users find it much cheaper and they don't end up stuck with obsolete machines.

      Many of the older machines can and do end up on the sale market and it is possible to buy one and own it, but it will still require service (lots for an old machine), toner, supplies, parts, and preventive maintenance. Xerox controls almost all the DocuColor parts, supplies, ink, and most of the trained CSEs so you pretty much have no choice but to sign on for a Xerox service contract even when you own the thing free and clear.

      Yes, there ARE trained key operators who can get in and do SOME maintenance chores but only Xerox can get parts and has the technical knowledge to use them.