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Wireless Networking Programming Hardware IT Technology

Reverse Engineered 802.11b+ Drivers 272

orv writes "When Andreas Mohr found that his new wireless networking card wasn't supported under Linux rather than returning the card and getting himself a supported one, he decided to set up a project to write his own drivers instead - http://acx100.sourceforge.net. Companies such as D-Link had initially promised to release linux drivers for these cards but later backed down from that promise and announced that Linux would not be supported and that customers should not hold on to the cards in the hope of getting them working, as shown on their current FAQ. Texas Instruments, the makers of the chipsets upon which these 802.11b+ cards are based refused to release code or specifications for the cards, no doubt for similar reasons that were recently discussed here. The fact that the current alpha release is certainly as good, and in some areas better, than the binary drivers that escaped from one of the card manufactureres speaks volumes for the quality and determination of the team to create their own drivers."
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Reverse Engineered 802.11b+ Drivers

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  • by kotj.mf ( 645325 ) on Monday July 21, 2003 @08:11AM (#6489564)
    This'll probably be at least tangentally addressed later, but what chipsets actually work in Linux? Understand I don't know nuthin about WiFi, other than some vague idea that I should get an Orinco-based card.

    Only reason I'm asking is that the salesdrone at OfficeDepot didn't know what the integrated wireless on the Averatec [averatec.com] 3150P was based on yesterday, and I'm not keen on paying an extra hundred bucks for the feature if it won't work in my OS of choice. Then again, I could save myself the dough and get the model w/o the integrated 802.11b, but still...

  • Re:Wha? (Score:3, Informative)

    by beezly ( 197427 ) on Monday July 21, 2003 @08:14AM (#6489586)
    Well, it's one way of doing reverse engineering.

    More generally, reverse engineering is (stolen from FOLDOC)...

    The process of analysing an existing system to identify its
    components and their interrelationships and create
    representations of the system in another form or at a higher
    level of abstraction. Reverse engineering is usually
    undertaken in order to redesign the system for better
    maintainability or to produce a copy of a system without
    access to the design from which it was originally produced.

    For example, one might take the {executable} code of a
    computer program, run it to study how it behaved with
    different input and then attempt to write a program oneself
    which behaved identially (or better). An {integrated circuit}
    might also be reverse engineered by an unscrupulous company
    wishing to make unlicensed copies of a popular chip.
  • Re:Wha? (Score:3, Informative)

    by Libor Vanek ( 248963 ) <libor.vanek@g[ ]l.com ['mai' in gap]> on Monday July 21, 2003 @08:15AM (#6489592) Homepage
    Some vendors (Promise D-Link 520+ etc.) are using their own 802.11b standard (WiFi) called 802.11b++ but they doesn't provide Linux drivers. Since this card should have 22 Mbit/s insted of standard 11 Mbit/s ppl want to use it in routers etc. but there are no Linux drivers. So some hackers (not crackers!) looked how does Windows drivers (or any other) control and use (when I call this card does this) this card and tries to implement it in Linux.
  • by orv ( 398342 ) on Monday July 21, 2003 @08:15AM (#6489596) Homepage
    Take a look at:- Jean_Tourrilhes [hp.com] howto for useful info on driver status.
  • by DaveHowe ( 51510 ) on Monday July 21, 2003 @08:27AM (#6489655)
    The problem is - some of the unsupported cards using this chipset used to use a different (eg Orinoco or Prism) chipset and have not updated the name of the card so that you think you are buying a supported card (as listed in many howtos) but in fact are getting a newer model with no available linux driver.
  • Re:DCMA Anyone? (Score:4, Informative)

    by gilesjuk ( 604902 ) <<giles.jones> <at> <zen.co.uk>> on Monday July 21, 2003 @08:35AM (#6489683)
    It'll probably happen, some stupid chip makers don't like details of registers in their products leaking out. They somehow think a competitor knowing the interface to one of their chips will help the competitor.
  • by BlowChunx ( 168122 ) on Monday July 21, 2003 @08:38AM (#6489697)
    Last I checked my Lucent chips were pretty much fully supported under Linux. It's mostly newer hardware chips that are not.

    This is not surprising, as Linux hardware support always lags a little. The same experience can be had with motherboard chipsets...(this is not a flame, just current reality).
  • Re:DCMA Anyone? (Score:1, Informative)

    by Anonymous Coward on Monday July 21, 2003 @08:43AM (#6489724)
    Skylarov came to the US. No one went to Russia to extradite him. And it wasn't the RIAA or MPAA. And your regexp is wrong, or at least very odd.
  • by Anonymous Coward on Monday July 21, 2003 @08:57AM (#6489795)
    [uh oh, we did make it to /. after all... ;)]

    Yep, that's a very bad thing indeed.

    So bad that we decided to dedicate a major part of the README file to it:

    ::::::

    --- AND FINALLY... ---

    Let me mention that we REALLY dislike the way very stupid hardware vendors
    name their cards containing DIFFERENT chipsets!!

    One of these vendors is SpeedStream/Siemens: a card that uses the same
    name "SS1021" is available in both Orinoco chip and ACX100 chip versions.

    Another one is D-Link: they have "DWL-650" and "DWL-650+".
    "DWL-650+" is simply an improved version of the "DWL-650", right?
    WRONG!
    The standard versions use Prism2.5, whereas the "+" versions use ACX100
    chipset. Good luck in finding a (correct) driver!!
    And it's even WORSE: I just found out that there is some newer
    version of the "DWL-650" out that also contains the ACX100
    (it uses the same hardware as the "+" versions).
    This BRAINDEAD STUPIDITY in device naming easily entitles D-Link
    for the "Most Braindead Hardware Vendor 2003" award. And of course
    they were also talking about developing another Linux driver for some time,
    without any results (although I guess that's because they wanted to
    develop it, but were not allowed to, unfortunately, so it's understandable).

    IF you dare to release cards with a different incompatible chipset
    that doesn't even have proper driver support for a popular alternative OS,
    then AT LEAST change the card name in order to let people know and discern
    which hardware to avoid like the plague, for heaven's sake!
    This is such a [CENSORED], I could [OUCH, CENSORED!]...

    ::::::

    It's one thing to decide to not release Linux drivers and/or specs for a popular chipset (and frankly, we sort of have to respect such a decision, even though it hurts a lot), but it's an ENTIRELY DIFFERENT (and much worse!) thing to release cards with DIFFERENT chipsets using the SAME card name as older, well-supported chipsets.
    That's a capital crime which should by punished by revoking any and all hardware development rights and/or licenses of the relevant company ;)
    (heck, or maybe I should have removed that smiley after all, since it IS a very infuriating action after all ;)

    But I think I should stop now since I already wrote most of that in the README file paragraph pasted above ;)

    Anyway, let me also mention that I'm glad how well the development process of our driver is coming along. We are fixing many bugs (and implementing many improvements!) on a daily basis, and the team work is definitely great!

    Also, we had several users donate money and/or hardware (access points!) to the main developers,
    which is very astonishing to me, but that's not to say that I don't like that :)
    In fact the access point that has been donated to me arrived today :))

    Finally, let's hope that we might even attract proper driver and spec support by Texas Instruments, by showing that a really good driver IS possible.
    (admittedly we're still "a bit" far off from a perfect driver, but we're definitely working on it :)

    That's it. Have fun using our driver! :)

    Andreas Mohr
  • Re:DCMA Anyone? (Score:5, Informative)

    by radon28 ( 593565 ) on Monday July 21, 2003 @08:58AM (#6489806)
    The DMCA isn't just a blanket law covering all instances of reverse engineering, regardless of the context. The DMCA covers reverse engineering in cases where it is being used for copyright circumvention, which driver hackers aren't trying to do. MOST Linux drivers have to be written this way. Don't get me wrong, the DMCA is still a pile of hot garbage. I just hate it when people are scared to do ANYTHING that might be useful because of the DMCA.
  • by orv ( 398342 ) on Monday July 21, 2003 @09:12AM (#6489879) Homepage
    Basically most work was done by disassembling a linux binary module for the chipset that leaked from one of the manufacturers.
    Additionally the behaviour of the card and correct initialisation process was determined by analysing the ARM disassembly of the firmware and watching the traffic that goes between the access point board and its embedded PCcard.
  • by Anonymous Coward on Monday July 21, 2003 @09:27AM (#6489948)
    I didn't see this posted anywhere, but if you read a little more about the topic, you would have found the probable reason for why the manufacturers aren't releasing drivers. It ISN'T some MS scheme to screw linux users. The manufactureres are affraid that releasing drivers will get them in trouble with the US government. Apparantley the card can be reconfigured to transmit on military/police/other "forbidden" frequencies. The manufacturers don't want to have to deal with the repercussions of releasing such a "weapon". Pretty stupid really, considering theres already an effort out there, with some success I hear, at reverse engineering the windoze driver, in order to reconfigure the transmit frequency.
  • Re:DCMA Anyone? (Score:4, Informative)

    by Monopolist ( 178137 ) on Monday July 21, 2003 @09:41AM (#6490045) Homepage
    IANAL, but I believe the DMCA explicitly *allows* reverse engineering when the goal is interoperability. Since the official FAQ for these cards says linux isn't supported, it seems to me the interoperability argument would hold.

  • Re:DCMA Anyone? (Score:3, Informative)

    by arkanes ( 521690 ) <<arkanes> <at> <gmail.com>> on Monday July 21, 2003 @09:44AM (#6490057) Homepage
    They'll claim that the firmware is copyrighted and that not releasing the specs is an access control mechanism, just like the people who're using the DMCA to sue about printer cartridges and garage door openers.
  • by Ed Bugg ( 2024 ) on Monday July 21, 2003 @10:07AM (#6490141)
    check out linux-bcom4301.sourceforge.net
  • by operagost ( 62405 ) on Monday July 21, 2003 @10:34AM (#6490342) Homepage Journal
    Linksys is guilty of the same crime with their 100baseT cards. They actually have used five different chipsets in a card called the LNE100TX. You have to pull the card and look at photos of the chips on their web site to figure out what driver to use. The lengths these cock-gobblers will go to, to save from having too many SKUs ...
  • Re:DCMA Anyone? (Score:3, Informative)

    by Gonarat ( 177568 ) * on Monday July 21, 2003 @10:50AM (#6490441)

    You are mostly right, except for Nr. 3. Skylarov came to the U.S. to give a talk on his program at Defcon, and was detained (captured) by the FBI in Las Vegas as he was getting ready to leave his Hotel and go to the airport. He ended up in San Francisco after being flown/driven several different locations. He was stuck in San Fran for several months before he was finally allowed to go home to Russia until the trial.

  • by Tackhead ( 54550 ) on Monday July 21, 2003 @10:54AM (#6490461)
    > Another one is D-Link: they have "DWL-650" and "DWL-650+". "DWL-650+" is simply an improved version of the "DWL-650", right? WRONG! The standard versions use Prism2.5, whereas the "+" versions use ACX100 chipset. Good luck in finding a (correct) driver!! And it's even WORSE: I just found out that there is some newer version of the "DWL-650" out that also contains the ACX100 (it uses the same hardware as the "+" versions). This BRAINDEAD STUPIDITY in device naming easily entitles D-Link for the "Most Braindead Hardware Vendor 2003" award

    To phrase this in language that even suits can understand:

    This is poor businss practice, not just it's difficult for anyone deploying these devices to know what they've bought (because who gives a fuck once you've got their money, right?), but because it adds to your support costs because when half of your DWL-650 doesn't work, and the guy deploying them calls your support drones - even at $1.99/h in India - it's a waste of your money to have them spend 20 minutes figuring out whether it's a chipset/driver problem that makes the difference between the working and non-working units.

    Your current way of screwing the customer is cutting into your margins because it increases your support costs. Find a more profitable way of screwing the customer. I think you could screw them more profitably by using different product names on different products.

  • by 0x0d0a ( 568518 ) on Monday July 21, 2003 @11:23AM (#6490667) Journal
    More than likely it was "It would be cool for all these countries to have wireless laptops" with absolutely 0 knowledge on the details of such an idea.

    I'm still a little dubious as to the actual value of laptops, much less with wireless support.

    Such things are very convenient, and certainly popular in offices, but I'm dubious that desktops don't provide much of the same benefit. Sure, some work may get done on the road, but some not (and the increasing availability of Internet access means that companies can decrease travel and save costs). Some work that might not have gotten done otherwise might get done at home, but honestly, most folks don't want to go home and then work more, and I think that most don't actually do that much at home (as an addition to work at work, not as a replacement). You can carry laptops to meetings, but honestly, about half the people where I work just use a notepad (partly because quick sketches are currently easier on paper). You usually aren't transcribing vast amounts of text, just jotting down names or some points to remember. So most of the benefits of laptops seem to be less big than one would thing.

    The downsides are significant. Laptops (with the notable exception of hard drives) tend to be less durable than desktops, and tend to get rougher treatment. This tends towards producing shorter lifespans. Laptops are a major target of theft, especially in the developing countries where they want to deploy these. Laptops are more expensive than desktops to produce, and manufacturers are still making higher profit margins on laptops. Most laptop manufacturers are big name (first world) companies, given the far greater engineering work required to put together a laptop. So it makes it harder to keep the funds spent *in* those developing countries when making purchases.

    Wireless networking is cute, but it costs a *lot* to deploy the thing all over as opposed to just the offices and conference rooms where you'd put wired Ethernet. If you just slap it in those two places, wired can be more expensive, but installation of wires can be done by local contractors, which keeps funds in country and produces jobs. Most people that I see doing actual work on their laptops tend to work in either meeting rooms or their offices. Usually, this translates to just meaning that they don't have to plug in a cable. Somewhat convenient, but possibly (especially given security and performance issues) not cost-effective. Wireless is still a bit of a luxury item.

    This wireless laptop initiative seems more based around what a laptop *company* would like to see happening than what's best for developing countries, IMHO.
  • by orv ( 398342 ) on Monday July 21, 2003 @03:08PM (#6492863) Homepage
    Indeed you discovered the link to the leaked binary drivers. However when the sourceforge project was started there were no binary drivers at all. Indeed it is a non-trivial task to decompile those drivers, and that was what was done to assist the development of the oss drivers. As you will note Dlink aren't providing or supporting those binary drivers you discovered either they've simply got fed up of all their customers asking them how to get their hardware running on linux and so added the link onto their FAQ.
    So no wash.

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