Or just take one of the open sourced recoveries and add a password
prompt to it. (Partial solution - it won't affect odin..)

Just need to make sure the recovery doesn't start adb or anything else
before getting a correct password.

On Thu, Aug 23, 2012 at 7:21 PM, Pau Oliva Fora <[email protected]> wrote:
> You'll have to implement this in the bootloader, which in most cases is
> closed source, so roughly you'll have to:
>
> - find the binary blob of the bootloader, probably in a factory image or
> dump it from the device
> - find the base address of the bootloader blob and disassemble it properly
> (use IDA pro)
> - find a place -big enough- where you can inject your own code for the
> password prompt
> - find a place in the early stages of device boot where you can place a jump
> instruction and branch to your code, this should be right after the
> bootloader code detects if the fastboot or odin button combinations are
> pressed.
>
> I'll suggest to write your code in C unless you are an arm assembly guru,
> and try to make it the smallest possible... if the password is correct, then
> it should jump back to the place right after where the execution was
> interrupted with your initial jump and continue with the normal bootloader
> process.
>
> Also, I wouldn't do the tests by flashing your patched bootloader directly
> into the phone (replacing the phone's stock bootloader), as a small mistake
> in your patches can totally brick the device. To properly test your patches,
> you'll need to find a way to place the bootloader in RAM (from Android) and
> jump into it, and to do this you'll need to disable interrupts, invalidate
> CPU caches, reset MMU, and continue execution from physical address space
> where you've copied the bootloader in RAM, this will simulate a reboot from
> bootloader but using your patched one in RAM instead of the stock one in
> NAND, not an easy task I guess... but if you have some progress, let us know
> :D
>
> Cheers,
>
>         pof
>
>
>
> On 08/23/2012 09:59 PM, Muddy Water wrote:
>>
>> This may be a redundant topic but I was wondering if anyone could point
>> me in the direction to begin to be able to implement an on screen
>> password before getting into recovery and odin. I've gotten my boot logs
>> off to see where to begin. Just wondering if anyone can assist.
>>
>> **Points I have already heard: it is pointless because it is recovery
>> etc...**
>>
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