Re: Another $17.4 Billion WASTED

Dave Head <rally2xs@xxxxxxx> wrote in
news:2ptpl4d9l3d85r3meles9nc09ge6dvqdjl@xxxxxxx:

On Wed, 31 Dec 2008 18:59:51 -0600, axiom <axiom@xxxxxxxxxxxxxx>
wrote:

On Wed, 31 Dec 2008 19:14:50 +0000, Eeyore wrote:

Scott in SoCal wrote:

Eeyore <rabbitsfriendsandrelations@xxxxxxxxxxx> wrote:
krw wrote:

Those outside vendors may assemble the parts but the IP in the
ECM is owned by the auto company.

And if they're not around to assert their IP ?

Then in 5 years when you get done reverse engineering their code
and producing your close they won't sue you.

Pathetically simple. Do-able in a week or less. Just change a few
lines or procedures. The IP's fucked.
http://en.wikipedia.org/wiki/Decompilation

Decompilers produce the equivalent of shrouded code (code in which
meaningful names of variables and functions have been replaced with
nondescriptive letters and numbers). Reverse-engineering a nontrivial
program from shrouded code is anything but "pathetically simple". It's
so difficult that many high-end midframe and mainframe applications
are distributed as shrouded source. (Distributing source instead of
binaries allows it to be compiled for the particular system it's being
run on, perhaps with user-selected features and compiler
optimizations).

Without ever having seen a decompiler work, I concluded that this
would have to be the case, since the compiler can have no knowledge of
the programmer's intent of the code.

WRT engine controllers,the code is going to interrogate input ports,compare
to data tables,or send instructions to output ports.
That's how engine modifiers have been able to develop "chips" and black
boxes to adjust the parameters for higher performance.
It's not as complex and secret as you believe.I suspect the skills are
already present in many of those aftermarket manufacturers.Companies like
AMG,Hondata,Superchips.(AMG gets info FROM Mercedes;their cars are sold
THRU Merc dealers,serviced and -warranteed- by the dealers.)

and once a company goes under,the code isn't proprietary anymore.


Hell, uncommented code from a programmer that is using
partially-descriptive choices of variable names and function /
procedure names can _still_ be a bitch to figure out. The shrouded
code could _still_ take 5 years fo decode a significant program,
especially if there are proprietary algorithms in use that you've
never seen before, and the programmer that wrote it was just following
the detailed software design document put together by the PHD that
invented the algorithm.

Its possible that you may never figure it out, if its a company trade
secret, and sufficiently complex.

Writing the code from scratch might be easier. 5 years, or 5
"man-years" is not at all unreasonable, I'd think.


A decompiler is the name given to a computer program that performs
the reverse operation to that of a compiler. That is, it translates
a file containing information at a relatively low level of
abstraction (usually designed to be computer readable rather than
human readable) into a form having a higher level of abstraction
(usually designed to be human readable).


For many years now micro-controllers designed for consumer products
have been designed to protect the ROM contents against being read and
disassembled or de-compiled. These devices are heavily integrated with
ROM, RAM, the CPU, I/O ports, and A/D and D/A converters all built
in. External data/address buses are implemented as serial ports from
which you do NOT have access to the internal data or address bus.
Where extra RAM is needed outside the chip, a good programmer will
still use the internal RAM for strategic variables and data.

And for this reason, building new ECC code from scratch might be the
_only_ reasonable alternative. And, that would likely be too
expensive, make your replacement ECC cost $2500, and turn your
otherwise $24,000 vehicle into a $0 lawn ornament, on which you still
owe $19,000.

All of this is not to be confused with the ROMS you can swap out that
tailor a vehicle's behavior to suit local emissions laws and fuel
quality or to improve racing performance. Those just contain data
tables and variable settings, and are not sufficient in themselves to
duplicate the car's computer.


HOW do you think they develop those ROMs?
They have to know how the computer is using the data.

--
Jim Yanik
jyanik
at
kua.net
.

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