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[mkgmap-dev] address search problem due to required "State" value

From Steve Hosgood steve at tallyho.bc.nu on Sat Aug 29 00:10:39 BST 2009

Florian and Gert wrote in reply to my appeal:
> On Fri, Aug 28, 2009 at 03:45:28PM +0100, Steve Hosgood wrote:
>> Detectives wanted!
>> Some or maybe all of the global index is in the .MDR file.
All suggestions are welcome, but I don't have cGPSmapper nor a workable 
copy of MapSource.

So if you guys can try out your ideas and post observations here, or add 
to the information on the wiki it will all be very welcome. There is 
some information embedded in Steve Ratcliffe's well-known (and ancient) 
.java program that partly decodes .mdr files, not all of this is in the 
wiki yet. Specifically, Ratcliffe seems to have deciphered some way into 
the MDR10/11 blocks that allegedly contain POI lists and indexes - that 
stuff isn't on the wiki yet. Someone better than I at reading .java 
files might do it better and quicker (hint, hint!). I'm a C/C++ 
programmer myself.

Other attack vectors would include decompiling MapSource and/or running 
it under a debugger to see what it does.

To be sure we will expect to be playing "Mastermind" with .MDR files for 
quite a while I suspect, tweaking known-good Garmin versions and seeing 
what happens when you try and load Garmin GPS units with the tampered 

It's all good fun.
But seriously - the more the merrier. There's a *lot* of work here.


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