A89: RE: rom checksum
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A89: RE: rom checksum
Where can I find info on RSA, MD5, etc .
I would love to know what you are talking about !!
Bye
Javier
PD Why are you so happy, is MD5 easier to hack,why ??
-----Mensaje original-----
De: Robin Kirkman <misty@drrobin.yi.org>
Para: assembly-89@lists.ticalc.org <assembly-89@lists.ticalc.org>
Fecha: Miércoles 8 de Diciembre de 1999 21:06 p.m.
Asunto: A89: rom checksum
>
>The calculator uses MD5 to compute the ROM checksum when it recieves a
>ROM, right?
>The general opinion is that it uses RSA, but has TI verified this?
>There -are- MD5 romcalls, though...
>
>Well... MD5 is not a public/private key algorythm.
>MD5 is a hashing algorythm.
>With a single key. (Not public/private)
>Guess what that means...
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>It means the key is in the ROM already!
>You just have to step through it, find the routine in the boot loader
>that does the actual MD5 hashing, and the key will be there too!
>Hehe, this means free app signing... ;)
>
>A bit for the crypto nuts:
>MD5 produces a 128bit checksum, whereas the 89 is rumored to have a 512
>bit one.
>Well, what's to stop TI from having FOUR 128bit checksums? That comes
>out to 512.
>Sneaky, eh?
>
>Well, i'll be off to go look for code which resembles MD5.
>Anybody who wants to join, feel free!
>--robin
>
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