Hey, here's something interesting you may want to take a look at:
<bertrik> there appears to be some kind of certificate at the end of both the osos and aupd part, has anyone ever tried to parse those? <taylor_> hmm <taylor_> no <taylor_> where? <taylor_> what offset? <bertrik> 0x4ae00 in osos.fw <bertrik> possibly it starts a little earlier on at 0x4adf0 <taylor_> ok <taylor_> I will take a look in a while <bertrik> 0xa4adf0 I mean <taylor_> What exactly is this anyways? <bertrik> as far as I know certificates, it contains a public key so you can verify other derived certificates <taylor_> hmm <taylor_> interesting <taylor_> something for you to also mention to #rockbox ;) * bertrik wonders what's at https://www.apple.com/appleca/0 <taylor_> :) <bertrik> this is probably not going to help hack anything, but it just might be interesting to see what's in it <bertrik> some pdf seems to suggest that apple uses x.509 certificates <bertrik> I wonder if you could verify the firmware image (a hash of it) using this certificate <taylor_> I'll check that out in a minute <bertrik> I wasn't referring to you specifically, just in general <taylor_> yeah I know. :) <bertrik> I think the numbers 0xa4a570 and 0xa4a5f0 in the header refer to the file signature and the certificate respectively <bertrik> if you add 0x800 to those offsets (start of firmware data), it matches with the location of the certificate <bertrik> the difference between those numbers is 0x80, or 128, which is probably the size of the signature <taylor_> Could this be useful for any type of decryption? <bertrik> I'm not sure. I think it helps to establish that the firmware is authentic, but might not have anything to do with the encryption itself _______________________________________________ Linux4nano-dev mailing list [email protected] https://mail.gna.org/listinfo/linux4nano-dev http://www.linux4nano.org
