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Eprom lock? — Parallax Forums

Eprom lock?

TJHJTJHJ Posts: 243
edited 2008-07-25 21:18 in Propeller 1
I cant seem to see it anywhere is there a ability to lock the eprom to prevent code theft for commercial use? Similar to a Pic Eprom lock, given enough motivation someone can get it but it stops the average person from taking it. So that not just any techie can touch two wires to the eprom and get what has taken who knows how long to develop.

Comments

  • Mike GreenMike Green Posts: 23,101
    edited 2008-07-25 15:18
    You don't see it because it isn't really there. There are all sorts of ways to make it hard to "make sense" of the contents of an EEPROM, but there's no built-in lock mechanism to prevent the contents from being downloaded. There have been many long forum discussions on this topic with many different suggestions. A lot depends on how much effort you want to go into to prevent theft. The easiest would be to use something like the SpinStamp that doesn't bring the EEPROM leads to the outside and pot it in some kind of epoxy compound that would make it difficult to probe the EEPROM chip without a lot of work. You could also make your own module that does the same sort of thing limiting physical access to the EEPROM. If you use a leadless (DFN) package for the EEPROM and the Propeller (QFN) and bury the EEPROM clock and data leads inside a multilayer board with the feedthroughs under the packages, that would make it quite difficult for the amateur thief once the thing was potted.
  • MarkSMarkS Posts: 342
    edited 2008-07-25 15:56
    I have to ask...

    While the Prop is powerful, what could anyone possibly do with the Prop that couldn't be reversed engineered in a matter of hours by a skilled hobbyist? Seriously, the code is just not going to be that complicated, which is, oddly, one of the strengths of the Prop. Locking it is just plain silly. If I wanted to, all I'd need to do is take a look at the board and play around with the device to get a pretty good idea of what to write. My code wont be 100% the same, but it will do the same, which is ultimately the same as downloading your code.

    I'd be more concerned that a less skilled hobbyist might reprogram the EEPROM and screw something up.
  • Mike GreenMike Green Posts: 23,101
    edited 2008-07-25 16:13
    This really has been discussed ad nauseum. The PIC (and other microcontroller) flash memory locks are fairly easily broken with the right professional equipment. They protect against the casual hobbyist and casual industrial thief and give a false sense of security, that's about all.
  • MarkSMarkS Posts: 342
    edited 2008-07-25 16:30
    Mike Green said...
    This really has been discussed ad nauseum. The PIC (and other microcontroller) flash memory locks are fairly easily broken with the right professional equipment. They protect against the casual hobbyist and casual industrial thief and give a false sense of security, that's about all.

    Exactly.

    Look at the Prop. The SPIN interpreter was encrypted and that was cracked, albeit with Parallax' blessing. It's ultimately a waste of time and resources.
  • hippyhippy Posts: 1,981
    edited 2008-07-25 16:32
    MarkS said...
    Seriously, the code is just not going to be that complicated, which is, oddly, one of the strengths of the Prop. Locking it is just plain silly.

    How do you know how complicated the code is or, more importantly, how valuable it is in terms of business ?

    One could create a market for a product which is nothing more than a pre-programmed SpinStamp selling at $500 per unit, but it's a non-starter if people realise they can buy their own SpinStamp and copy the Eeprom over. The business would likely collapse from end-users doing that and others offering the exact same product cloned at a cheaper price.

    I wouldn't call it at all silly to lock code to secure business profitability. It's not how complicated the code is but what it can be sold for.

    MarkS said...
    If I wanted to, all I'd need to do is take a look at the board and play around with the device to get a pretty good idea of what to write. My code wont be 100% the same, but it will do the same, which is ultimately the same as downloading your code.

    I'm afraid that is usually easier said than done, but if you are prepared to put the time and effort into it as the originally developer did and have the necessary skills then good luck to yourself. While it may ultimately be the same there's a significant difference between that effort and cloning an Eeprom which even a trained monkey could do.
    MarkS said...
    Look at the Prop. The SPIN interpreter was encrypted and that was cracked, albeit with Parallax' blessing. It's ultimately a waste of time and resources.

    Knowing that all locks can be broken doesn't mean that we don't fit locks to cars, houses and other property.

    No lock is infallible but it doesn't mean it's not worthwhile fitting them.

    Post Edited (hippy) : 7/25/2008 4:38:59 PM GMT
  • MarkSMarkS Posts: 342
    edited 2008-07-25 16:40
    And there are legal options that can be taken at that point. I believe that reverse engineering is still illegal and cloning an EEPROM is at the least a violation of copyright. Any individual or company that is willing to take those steps is probably willing to go further.

    My point is that if someone wants it bad enough, they'll get it. Locking your code deters the casual hacker/hobbyist and they're probably not going to be a threat anyway. The threat comes from those that have the time, resources and financial motivation to crack the lock and steal your code.
  • hippyhippy Posts: 1,981
    edited 2008-07-25 17:01
    Sure, if people want it bad enough they do it, and nothing can prevent that. I think we all recognise that, but it was the notion that it was "silly" to consider any deterrence which I don't accept.

    I lock my car not to stop it being stolen but to make it harder to do so. I expect the manufacturer put the key-code ignition system in place for the same reason.

    Would you buy a car which didn't have a lock and just a push-to-start button ? What would you say to a manufacturer who said you didn't need a key or lock because it wouldn't stop a determined thief taking it anyway ?

    I'm not trying to re-run the should it shouldn't it have some protection mechanism for the Propeller, just addressing the notion of security which I don't think can be so quickly dismissed.
  • MarkSMarkS Posts: 342
    edited 2008-07-25 17:11
    I understand the reason for locks in the real world. However, we all here are speaking from a rather highly technical background, and thus, our views are biased. What we do, what we make, is near magic to the rest of the world. Any idiot can smash a window, jab a screwdriver into the ignition and steal a car. From a real world perspective, it takes a great amount of skill and knowledge to clone an EEPROM. If you understand what "cloning an EEPROM" means, you probably have the technical expertise to crack an EEPROM lock or the ability to quickly learn.
  • VIRANDVIRAND Posts: 656
    edited 2008-07-25 18:29
    MarkS said...
    I believe that reverse engineering is still illegal

    In what country? I don't believe it ever was illegal. I disagree with EULAs.

    IP is only patent or copyrighted. You may still disassemble it.
  • hippyhippy Posts: 1,981
    edited 2008-07-25 20:10
    MarkS said...
    From a real world perspective, it takes a great amount of skill and knowledge to clone an EEPROM. If you understand what "cloning an EEPROM" means, you probably have the technical expertise to crack an EEPROM lock or the ability to quickly learn.

    This is where I disagree. One's a case of having the tool to copy the Eprom and being able to follow the instructions, the other requires real ability. It's like people running software to unlock phones, bootleg music, video and software and strip out DRM. That they can use the tools doesn't mean they have the capabilities to create that software themselves. All most know is; do this and it works.
  • TJHJTJHJ Posts: 243
    edited 2008-07-25 21:18
    Sorry didnt mean to create an issue, but In my opinion it all comes back to the honest thief. The person who really is not a bad person but takes something because it is there, causing those a headache and not considering it. But the real thief will be able to get it no matter what.
    Eg Having a motorcycle and leaving it outside with the keys in it, its bound to be taken, but if someone really wants to steal it, it does not matter how many locks, bolts, extra securities I place on it, the real thief will get it. I once had a trunk lid stolen off a car, the car was locked, they took the trunk off with out placing a scratch anywhere. It was like a professional body shop had just removed it. It turns out there was later a large "Ring" of thief's taking trunk lids for the spoilers to resell them and were professionals. IMO there was nothing that could be done.

    So that being said the Pic's false sense of security is to stop the honest thief, and I would love to see that ability in the prop. We all know we cant stop some one who really wants it, but we would like to stop the average guy from taking it.

    TJ

    Edit* It still is magic most days.
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