secret8gent

^^^ that's sorta what i was saying regarding copying.
(there is significant risk without detailed knowledge of the flash)
https://www.rx8club.com/showpost.php...9&postcount=62

to me, the utility of flashing the ecu and software to edit/tune a flash are really two separate things.

ECU flash tuning solution providers bundle the two actions together with their products. Perhaps they are relying on some implicit security by tying together both mechanisms, but unless they are modifying the system to no longer be J2534 compliant (which COBB does?), there has always been the risk that another conforming flasher/reader could manipulate (copy, overwrite) their output. (this was one of lola's concerns, i think)

I suppose a provider of a flash editor could simply disable the READ logic to protect from copying, and leave the WRITE part to make the ECU flash a one-way device. That way you could always flash it back to stock and start over. (I don't know how feasible it is to do - there could be some significant drawbacks)

Now that i think about it for a second, personally i am more drawn to a standard compliant flasher/reader, and standalone editor combination - i guess part of me doesn't like my ecu being locked down completely.

This leads me to a hypothetical question:
What if my COBB AP breaks or is stolen, is my ECU stuck in the same state forever? (someone says the dealer cannot reflash it...)

Hymee

iTrader: (1)

If you have no way to read the ECU, then how can you keep a copy of your stock flash???

You can't make the flash "non passthrough compliant". It will just not be compliant with the factory tool.

(Food for thought. I've got it all covered in my mind, and product for that matter )

Cheers,
Hymee.

CnnmnSchnpps

iTrader: (1)

Good point. Unless they have a backdoor for getting in...

NaarLeven

Well **** it took me approx 5 sec with a translator, so are you saying in about 500 seconds I could do this myself?

r0tor

iTrader: (1)

they have great customer service

secret8gent

well you would copy it to your computer before you upload a flash that locks out reading. or you could download the appropriate stock flash from the dealer tech net. Or perhaps when flashing is more prevalent in the future, the rx8club could have such a resource available.

The physical flash memory itself would always be accessible (write-able/read-able), but it could create the need to open up the unit and wire to the memory directly; unless you're saying that the pass-through read/write interface is already directly connected to the memory and not handled (or abstracted) by the software running on the ECU (which could be modified to create the scenario i described).
If that's the case I don't know how COBB is locking others flashers out - are they only locking the dealer out (because the standard dealer tool has some behavior they're exploiting - version checks or something) ?

My idea might not even be possible because read access could be required for the action of writing (checksums or safety checks or responses, etc)

if there is some method to bypass their marriage lockout, then that would seem to be the case.

I don't doubt that~
though i am curious about what 'other' changes occur when you marry the AP besides the tune.

--

thanks for the replies!

Hymee

iTrader: (1)

You picked the right encoding, which wasn't hard that hard was it? Should I post another one?

Cheers,
Hymee.

CnnmnSchnpps

iTrader: (1)

Do it do it! I missed the first one

chariotdriver

This leads me to a hypothetical question:
What if my COBB AP breaks or is stolen, is my ECU stuck in the same state forever? (someone says the dealer cannot reflash it...)[/QUOTE]

It will be locked until you acquire a second re-flasher from the same company. Once the ECU is locked out, the factory tool can neither read or write the ECU Flash memory via the OBD-II connector. The diagnostic and OBD functions of the ECU still work.

secret8gent

i think i need to read up on exactly what the encrypted flash does.

can encrypted files be read back out? (in an encrypted state - or do you have supply decrypt key to read it, or can they not be read at all?)

that might give me the answers i'm looking for.

lolachampcar

I think data goes on and off the PCM unencrypted (Mazda's firmware which by copy write really should not be changed). I am guessing the encryption happens on the tool or PC side.

The real road block is changing the PCM security so that only the tool that did the deed knows how to get back in.

Hymee

iTrader: (1)

Cheers Hymee.

secret8gent

that's sort've what i was getting at with one of my earlier posts in this thread.

I think at this point, I'll wait for a bit and see.