FC: More on Rep. Boucher's nastygram and copy-protected CDs

From: Declan McCullagh (declanat_private)
Date: Mon Jan 07 2002 - 22:01:46 PST

  • Next message: Declan McCullagh: "FC: U.S. Supreme Court won't hear toiletcam lawsuit"

    Thanks, all, for the replies. The breadth of legal and technical knowledge 
    among Politech readers is always impressive.
    
    Previous message:
    
    "Rep. Boucher sends nastygram to music firms re: copy-protected CDs"
    http://www.politechbot.com/p-02997.html
    
    -Declan
    
    *********
    
    Date: Mon, 07 Jan 2002 12:26:21 -0500
    To: declanat_private
    From: Jon Zittrain <zittrainat_private>
    Subject: Re: FC: Rep. Boucher sends nastygram to music firms re: 
    copy-protected CDs
    In-Reply-To: <5.1.0.14.0.20020107103428.029e6990at_private>
    
    I wholeheartedly agree with the spirit of the idea that new technical copy 
    protection schemes could upset the balance, such as it is, struck by 
    copyright law.  Copyright law's protectable property rights are by no means 
    absolute, as others have pointed out with such examples as limited temporal 
    term, fair use exceptions, and the first sale doctrine, which says that 
    after I buy a book the seller/publisher has no business telling me that I 
    can't lend it or resell it to someone.
    
    But the Audio Home Recording Act was drafted by the publishers -- I don't 
    see how anyone reading it could readily find it to say that it prohibits 
    private, technical copy protection schemes that, to be sure, trample 
    copyright's balance.  Similarly, the royalties owed publishers on things 
    like DAT unit and blank tape sales (an extraordinary law!), don't seem to 
    be conditioned on the devices' incorporating an ability to make 
    noncommercial copies..  Congress would do well to go ahead and pass such a 
    law regarding mass publishers' "copyduty" -- and I'm hoping today that the 
    Supreme Court will announce that it's taking the case of Eldred v. 
    Ashcroft, which challenges the Sonny Bono Copyright Term Extension Act of 
    '98 as an unconstitutional retroactive extension of "limited terms."  But I 
    don't think a "copyduty" law is already on the books.  Perhaps the next 
    step would be for Rep. Boucher to get a hearing going on what a copyduty 
    law might look like.  The publishers would come out of the woodwork to 
    fight it.
    
    Here's the provision in question: 
    <http://caselaw.lp.findlaw.com/casecode/uscodes/17/chapters/10/subchapters/d/sections/section_1008.html> 
    -- it just says that the record companies can't sue over people making 
    certain kinds of copies, not that they have to allow those copies to be made.
    
    Title 17, Section 1008. Prohibition on certain infringement actions
    
           No action may be brought under this title alleging infringement
         of copyright based on the manufacture, importation, or distribution
         of a digital audio recording device, a digital audio recording
         medium, an analog recording device, or an analog recording medium,
         or based on the noncommercial use by a consumer of such a device or
         medium for making digital musical recordings or analog musical
         recordings.
    
    ...JZ
    
    
    Jon Zittrain
    Harvard Law School
    Jack N. & Lillian R. Berkman Assistant Professor of Entrepreneurial Legal 
    Studies
    Faculty Co-Director, Berkman Center for Internet & Society
    <http://cyber.law.harvard.edu>
    
    *********
    
    Date: Mon, 7 Jan 2002 12:19:05 -0500
    To: declanat_private
    From: Marc Rotenberg <rotenbergat_private>
    Subject: Re: FC: Rep. Boucher sends nastygram to music firms re:
      copy-protected CDs
    Cc: hoofnagleat_private
    
    There is a new page today up at the EPIC site
    (epic.org) on Digital Rights Management. It's
    very extensive.
    
    Marc.
    
    *********
    
    Subject: Re: FC: Rep. Boucher sends nastygram to music firms re:
             copy-protected CDs
    From: Christopher Cramer <chris.cramerat_private>
    To: declanat_private
    Date: 07 Jan 2002 13:05:45 -0500
    
    Declan,
    
    There are a handful of different/competing copy protection mechanisms.
    They all involve writing CDs in ways they weren't meant to be written
    and most take advantage of the fact that CD players are dumb while CDROM
    drives are more intelligent.  For example, one mechanism writes bad
    checksums for some of the good blocks of audio data.  Most CD players
    will go ahead and play right through it.  A CDROM drive will see the bad
    checksum and return no data to the program.  This will result in static
    on a ripped or copied CD.  Other mechanisms involve writing bad table of
    contents information.  There is a discription of one of the copy
    protection mechanisms (SunnComm's Digital Content Cloaking Technology)
    at the URL:  http://uk.eurorights.org/issues/cd/charley_pride.shtml
    
    Hope this helps.
    
    -Chris
    
    --
    Christopher E. Cramer, Ph.D.
    Information Technology Security Officer
    Duke University,  Office of Information Technology
    253A North Building, Box 90132, Durham, NC  27708-0291
    PH: 919-660-7003  FAX: 919-660-7076  email: chris.cramerat_private
    
    *********
    
    From: "Aaron Miller" <amillerat_private>
    To: <declanat_private>, <politechat_private>
    References: <5.1.0.14.0.20020107103428.029e6990at_private>
    Subject: Re: Rep. Boucher sends nastygram to music firms re: copy-protected CDs
    Date: Mon, 7 Jan 2002 12:32:36 -0500
    
    Hi Declan -
    
     > [Does anyone have a pointer to a detailed technical description of how the
     > copy protection mechanism works? --Declan]
    
    http://www.cdrfaq.org/
    
    Section 2-4... is an excellent place to start - I will continue to scour my
    resources and see if I can find a more techincal explanation of how the
    technology actually works.
    
    Be well -
    
    Aaron Miller
    
    *********
    
    Date: Mon, 7 Jan 2002 14:02:26 -0500 (EST)
    From: "J.D. Abolins" <jda-irat_private>
    To: Declan McCullagh <declanat_private>
    Subject: Re: FC: Rep. Boucher sends nastygram to music firms re: 
    copy-protected CDs
    
    FWIW: Some URLs I found in a quick check for audio CD copy protection
    techniques (unevaluated):
    
    MacroVision's Audio Protection Info Page
    http://www.macrovision.com/solutions/newtech/safeaudio.php3
    
    Article about the MacroVision method may have already been cracked
    (mentions a Dutch hacker site; no URL given)
    http://www.audiorevolution.com/news/0701/24.safeaudio.shtml
    
    Quick Overview of some types of CD copy protection from a UK CD tech site
    http://www.disctronics.co.uk/technology/cdaudio/cdaud_copyprot.htm
    
    MidBar Tech (mfg of one copy protection scheme; technology link provides
    brief overview)
    http://www.midbartech.com/
    
    IEEE article on why Copy Protection is Doomed. (I don't have member
    access)
    http://www.computer.org/computer/co2001/rx048abs.htm
    
    CD-ROM Guide Site (general info clearinghouse)
    http://www.cdrom-guide.com/
    
    Article about the trouble brewing over CD copy protection (seems to be
    full of useful pointers to other sites)
    http://www.computertracker.com/2001/7-Aug/page30.html
    
    CD Burner 2002 Software (claims to work past various copy protection
    schemes)
    http://www.cybercitysoftware.com/cdbur20prof.html
    
    J.D. Abolins
    Meyda Online -- Infosec & Privacy Studies
    New Website: http://www.MeydaOnline.com
    
    *********
    
    Date: Mon, 7 Jan 2002 17:14:57 +0000 (GMT)
    From: Martin Keegan <mk270at_private>
    To: Declan McCullagh <declanat_private>
    cc: jimat_private
    Subject: Re: FC: Rep. Boucher sends nastygram to music firms re: 
    copy-protected  CDs
    
    On Mon, 7 Jan 2002, Declan McCullagh wrote:
    
     > [Does anyone have a pointer to a detailed technical description of how the
     > copy protection mechanism works? --Declan]
    
    Try the link "Dan Ackroyd's in-depth investigation of the Charlie Pride
    CD's copy-protection" and some of the others on this page:
    
    http://uk.eurorights.org/issues/cd/docs/
    
    Mk
    
    *********
    
    From: "D McOwen" <dmcowenat_private>
    To: <declanat_private>
    Subject: RE: Rep. Boucher sends nastygram to music firms re: 
    copy-protected  CDs
    Date: Mon, 7 Jan 2002 12:31:38 -0500
    
    Declan,
    
    I will look for the white papers for you. In the mean time the main
    difference between consumer music only CD players and players in computers
    is that the computer players have error correction software built in while
    music only players do not. So the RIAA is obviously using that built in
    normally good feature and turning it into a bad feature by purposly burning
    the discs in a way that the standard error correction software would see the
    disc as so bad it cannot be played. To get just a little more technical
    without the white paper in hand, for example the music only CD player simply
    has a time out, only after a certain standardized long period that it cannot
    read bits from the disc would it actually error out. A music only CD player
    would actually display ERROR on the display at that point and no longer play
    any tracks or music until you open the CD door, re-seat the disc and let the
    player read all the track info, basically starting over manually. A computer
    player would attempt to restart on it's own.
    
    David McOwen
    
    *********
    
    Subject: RE: Rep. Boucher sends nastygram to music firms re: copy-protected CDs
    Date: Mon, 7 Jan 2002 09:38:13 -0800
    From: "Scott Neugroschl" <sneugroschlat_private>
    To: <declanat_private>
    
     > -----Original Message-----
     > From: Declan McCullagh [mailto:declanat_private]
     > Sent: Monday, 07 January, 2002 7:53 AM
     > To: politechat_private
     > Subject: FC: Rep. Boucher sends nastygram to music firms re:
     > copy-protected CDs
     >
     >
     > [Does anyone have a pointer to a detailed technical
     > description of how the
     > copy protection mechanism works? --Declan]
    
    Declan,
    
    I believe that the CD in question (Universal's soundtrack for
    "The Fast and the Furious") used Cactus Data Shield.  Check
    out http://www.midbartech.com.
    
    There have also been many discussions of this over on slashdot
    (http://slashdot.org).
    
    
    Scott
    -- My opinions are my own and do not purport to reflect those of my employer
    
    *********
    
    From: Jason Thomas <jthomasat_private>
    To: "'declanat_private'" <declanat_private>
    Subject: RE: Rep. Boucher sends nastygram to music firms re: copy-protected CDs
    Date: Mon, 7 Jan 2002 12:39:05 -0500
    
    Declan,
    
    Usually I am very skeptical of fair use claims from public domain advocates
    in that they attempt to take a defense against infringement and turn it into
    a positive right.  However, in this instance I believe Rep. Boucher is
    correct to highlight the way copy protection infringes on the fair use
    rights implicit to the '92 AHRA.
    
    What seemed, at passage, to be a way to collect royalties for simply
    acknowledging reality has turned into a legal obstacle.  It is a shame that
    this perfectly defensible attempt to guard against unauthorized reproduction
    may not be legal, but the industry has brought it on itself.  By demanding
    that government socialize the costs of time-shifting reproduction through
    the AHRA, the RIAA welcomed this type of scrutiny.  Contrast this situation
    to Microsoft Windows XP, which prevents multiple installations and other
    fair use(s).  Microsoft is well within its legal rights to prevent
    unauthorized reproduction because its collects no royalties from blank
    diskette and CD-ROM sales.
    
    While public domain advocates may decry both practices, this distinction is
    not marginal.
    
    --------------------------------------------
    Jason M. Thomas
    Economic Policy Analyst
    Citizens for a Sound Economy
    1250 H Street NW, Suite 700
    Washington, DC 20005-3908
    phone: (202) 942-7621, fax: (202) 783-4687
    www.cse.org
    
    *********
    
    Date: Mon, 07 Jan 2002 13:49:03 -0500
    From: Alan Ritzert <juggalo1at_private>
    To: declanat_private
    Subject: Re: FC: Rep. Boucher sends nastygram to music firms re: 
    copy-protected  CDs
    
    1. A list of current known "corrupt CDs" can be obtained at 
    http://www.fatchucks.com/corruptcds/corrupt.html
    
    2. This isn't exactly detailed or too technical, but it's a link describing 
    various methods of cd corruption. 
    http://uk.eurorights.org/issues/cd/overview.shtml
    
    *********
    
    Date: Mon, 7 Jan 2002 19:04:56 +0000
    To: Declan McCullagh <declanat_private>
    Cc: Martin Keegan <mk270at_private>
    Subject: Re: FC: Rep. Boucher sends nastygram to music firms re: 
    copy-protected  CDs
    Message-ID: <20020107190456.A32513at_private>
    References: <5.1.0.14.0.20020107103428.029e6990at_private> 
    <Pine.GSO.3.96.1020107171352.26534P-100000at_private>
    Mime-Version: 1.0
    Content-Type: text/plain; charset=iso-8859-1
    Content-Disposition: inline
    Content-Transfer-Encoding: 8bit
    From: Jim Peters <jimat_private>
    X-UIDL: d8ae2c02042ad1e688dc8afc3d200713
    
    Martin Keegan wrote:
     > On Mon, 7 Jan 2002, Declan McCullagh wrote:
     >
     > > [Does anyone have a pointer to a detailed technical description of how 
    the
     > > copy protection mechanism works? --Declan]
     >
     > Try the link "Dan Ackroyd's in-depth investigation of the Charlie Pride
     > CD's copy-protection" and some of the others on this page:
     >
     > http://uk.eurorights.org/issues/cd/docs/
    
    Also check out my article on that page.  About half-way down you'll
    find some links to NewScientist Online.  These are by Barry Fox, and
    give good technical info.  Although one of these was withdrawn under
    pressure from Midbar, the original patent is still viewable here:
    
       http://164.195.100.11/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=/netahtml/srchnum.htm&r=1&f=G&l=50&s1=%276208598%27.WKU.&OS=PN/6208598&RS=PN/6208598
    
    Here's a quote:
    
     > Thus, during playback, the substituted audio data portion 58 is
     > provided to the digital-to-analog converter as normal data,
     > resulting in audio distortion and POTENTIALLY DAMAGING THE OUTPUT
     > CIRCUITRY.
    
    What fun !
    
    I should probably put that link into the article.  (Okay, done).
    
    Cheers -
    
    Jim
    
    -- 
      Jim Peters                  (_)/=\~/_(_)                        Uazú
                               (_)  /=\  ~/_  (_)
      jim@                  (_)    /=\    ~/_    (_)                  www.
      uazu.net           (_) ____ /=\ ____ ~/_ ____ (_)           uazu.net
    
    
    *********
    
    Date: Mon, 7 Jan 2002 22:46:41 +0000
    From: John Eisenschmidt <jweisenat_private>
    To: Declan McCullagh <declanat_private>
    Subject: Re: FC: Rep. Boucher sends nastygram to music firms re: 
    copy-protected CDs
    Message-ID: <20020107224641.C4171at_private>
    References: <5.1.0.14.0.20020107103428.029e6990at_private>
    Mime-Version: 1.0
    Content-Type: multipart/signed; micalg=pgp-md5;
             protocol="application/pgp-signature"; boundary="i7F3eY7HS/tUJxUd"
    Content-Disposition: inline
    
    Declan,
    
    CNET did a pretty good writeup in November:
    
    http://news.cnet.com/news/0-1005-200-7852921.html
    
    I saw this on Saturday on ZDNet, and I immediately wrote my Representative 
    (Jim Moran) and asked him to join with Rep. Boucher and make the recording 
    industry accountable for this.
    
    I've been extracted my CDs to MP3 since 1996, and I follow not only the 
    letter of the law but the spirit. As soon as I get a CD it's extracted so I 
    can listen at home, at work, in the car, and on my Rio. I don't have to 
    carry hundreds of CDs with me everywhere, and I don't share my MP3s and I 
    don't download copywrited music from the internet.
    
    Copywrited CDs stop me from enjoying the music I buy legally not only in 
    preventing me from extracting them, but they don't play correctly in some 
    CDROMs as well, meaning I can't listen to them anywhere.
    
    Sites like Fat Chucks http://fatchucks.mycool.com are trying to make people 
    awar
    e that the recording industry is trying to slip this under the rug. You 
    can't even return these CDs as defective, because most places only let you 
    exchange defective music and videos for the same title (which is also 
    "defective").
    
    John Eisenschmidt
    
    *********
    
    From: "D McOwen" <dmcowenat_private>
    To: "Declan" <declanat_private>
    Subject: So easy to put computer CD players in perpetual Error mode
    Date: Tue, 8 Jan 2002 00:20:58 -0500
    Message-ID: <NCBBLLCKEFIGAFOKNBDLEEDPCIAA.dmcowenat_private>
    MIME-Version: 1.0
    Content-Type: multipart/alternative;
             boundary="----=_NextPart_000_0002_01C197DA.58796520"
    X-Priority: 3 (Normal)
    X-MSMail-Priority: Normal
    
    Declan,
    
    It's so easy it's not funny. It is just as I thought. You simply put the CD 
    in perpetual Error Mode for a Computer type CD player by purposely burning 
    a track error in. That is just outright mean. I put in BOLD (continue the 
    pattern) down below where the intentional errors would affect a computer 
    player but not a music only player.
    
    <http://www.ee.washington.edu/conselec/CE/reports/Group.1/matt_page_individual/subcode.html>http://www.ee.washington.edu/conselec/CE/reports/Group.1/matt_page_individual/subcode.html
    
    
    
    SUBCODE ON THE COMPACT DISK
    
    
    Did you ever wonder just how a CD player new exactly where it was on the 
    disk at all times, even if it skipped? Did you ever think about how some CD 
    players know the name of the disk before you even play a song? These and 
    other similar little tricks are done with a portion of the CD's data called 
    subcode. Out of every 291 bits of data that come off the disk, 8 of them 
    are devoted to this subcode. The 8 bits are given letters designating their 
    usage: P, Q, R, S, T, U, V and W. Most players actually only use the Q bit.
    
    
    The Q bit
    
    You might be wondering how much usefull information can be derived from 
    just one bit? Well, the CD player gets around this apparantly small amount 
    of data by waiting until 98 of these bits have been received and then 
    decoding the information. It would be like you sending a letter to your 
    friend one character at a time. This all happens so quickly though that an 
    entire 98 bit block (called a subcode block) is available 75 times every 
    second. It doesn't seem like such a small amount of data now, does it?
    
    Within the Q channel (or the Q subcode block) there are basically 4 types 
    of information: Data, Control, Address, and some Error Detection Code. The 
    format of the Q channel is seen in the diagam below:
    
    figure 3.30
    
    There are 4 bits devoted to control information. The first bit tells the CD 
    player whether the CD has 2 or 4 audio channels. Although no CD player I've 
    seen has 4 channels output, it might be the next advance in the technology. 
    Imagine listening to a live concert with all the real depth and sound 
    surrounding you. Currently the closest thing to this is to use DSP to delay 
    a copy of the 2 channel signal (along with some fancy processing) and send 
    it to the rear speakers. Using all four channels of the CD as it is capable 
    of would sound much more realistic. The second bit isn't defined. The third 
    bit is used for a sort of copy protection. If the bit is set, it tells a 
    digital recorder listening to the data not to record. This is why a DAT 
    wont record all of your CD's so you can take them back and not have to pay 
    for them. Record companies thought about this in advance... The fourth bit 
    of the control is to indicate whether or not the CD was recorded using 
    pre-emphasis. Pre-emphasis in CD players works a lot like the original 
    dolby noise reduction techniques used to get better quality recordings on 
    analog tapes. The process stems from the idea that most of the noise in a 
    recording occurs in the high end of the frequency spectrum. The master 
    recording (usually a tape) is assumed to be without noise or distortion. 
    The high frequencies are amplified and then recorded onto the CD disk. The 
    recording process introduces a little noise in the high end, which would be 
    the same amount whether or not the original signal was amplified. The CD 
    player playing the recorded disk reads off the music and attenuates the 
    high end frequencies, reducing the noise from the recording process greatly 
    and returning the signal back to its proper level of amplification. If the 
    manufacturer of the disk used this pre-emphasis process, the fourth bit of 
    the control would be set to 1, telling the CD player to turn on the 
    de-emphasis circuit to perform the attenuation.
    
    After the control information in the Q channel comes 4 bits of address 
    information. These 4 bits tell the CD player what to look for in the next 
    block in the Q channel (the Data block). There are 3 different varieties of 
    Data blocks, mode 1, mode2 and mode3. The 4 bits of address indicate which 
    of the three types the Data block is.
    
    
    Data block mode 1
    
    The information in the Data block when it is in mode 1 is different 
    depending upon whether or not you are in the "lead-in" area. The lead-in 
    area is the first area on a disk and gives such information as the table of 
    contents for a disk. The format of the Data block when it is in mode 1 is 
    shown below:
    
    figure 3.31
    
    The lead-in area is indicated by the first TNO field being 8 bits of zeros. 
    When in the lead-in area, the Point field specifies a track number, from 0 
    to 99. The Min, Sec and Frame fields give the absolute starting time of 
    that track from the end of the lead in area in Minutes, Seconds and Frames 
    respectively (there are 75 frames in a second). If the Point field has the 
    hexadecimal number A0 in it, the Min field contains the number of the first 
    track, with the Sec and Frame fields set to zero. If it contains and A1, 
    the Min field contains the number of the last track on the disk. Finally, 
    if the Point field has an A2, the Min, Sec and Frame fields give the 
    absolute time of the end of the music (which would indicate total disk play 
    time). The Q-channel in the lead-in area is repeated 3 times for every 
    entry in the table of contents to introduce redundancy in case of errors. 
    The Q-channels as they come of the disk would give data like this:
    
    Track 1 start time, Track 1 start time, Track 1 start time, Track 2 start 
    time, Track 2 start time, Track 2 start time ...
    
    ... Track 99 start time, Track A0 info, Track A0 info, Track A0 info, Track 
    A1 info ...
    
    and so on.
    
    When the disk is in the program area, that is when it's playing songs, the 
    data area in mode 1 contains the current track number, the amount of time 
    since the beginning of the track, the amount of time from the beginning of 
    the CD, and 8 bits which can be used to indicate indexes in the track, like 
    bookmarks. Up to 99 indexes can be encoded in each track. Using this data, 
    your CD player gives you a readout on the display of how many seconds have 
    elapsed, what track you're on etc. Because this information is encoded 
    right along with the music, you can skip the CD to a completely new area, 
    and it will always tell you exactly where it is on the CD.
    
    
    Data block mode 2 and mode 3
    
    When the Data block is in mode 2 or 3 (indicated by a 2 or 3 in the 4 bits 
    of address in the Q channel), different information can be obtained, as can 
    be seen in the breakdown of the Q-channel below:
    
    []
    
    The data in mode 2 contains a sort of bar-code for the disk. It's a catalog 
    number which uniquely identifies the disk and it remains constant for every 
    mode 2 data block. This is how some CD players know the name of the disk. 
    They read the disk to get the catalog number and looks it up in a table 
    which maps catalog number to name of disk. The table is usually built by 
    the user. All the user has to do is to type in what the disk should be 
    referred to the first time it gets put into the CD player. Other usefull 
    things can arise from the catalog nuber besides disk names, one can program 
    in their favorite songs and put that in memory as well. When one plays the 
    disk again, all the favorites are ready to go.
    
    Mode 3 (if present) has a little more detail about the origin of the disk. 
    It contains a code for the recording which indicates the country, owner, 
    year of recording and a serial code. This data can change from track to 
    track as the information refers to the particular song and not necessarily 
    to the whole disk.
    
    
    
    
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