RSA on ES series ES7500

[user644]

I have ES7500 smart-TV. Firmware names: T-ECPDEUC ****.**. Unpacking exe file.
Each file in firmvare has RSA(?) signature in small files *.cs(256 bytes), *.vs(256 bytes), *.cmac(132 bytes).
I can unpack and decrypt them with samygo perl script, i can encrypt back them, but tv is not updating with repacked firmware. Repacked firmware is newer, than existing, CRC count is right.

What are the small files? Is this RSA sigs? If it is true, where is public key? And how to repack T-ECPDEUC firmware and install it on ES7500-series smartTV


ES7500=ES8000

[arris69]

...where is public key?

in exeDSP, just for completition: the private key is in korea...

And how to repack T-ECPDEUC firmware and install it on ES7500-series smartTV

you have to encrypt and sign it with the private key...

[user644]

ok, i got 188 bytes public key in PEM format. Which of .vs, .cs, .cmac files are signatures? Or signature is in the end of .sec file? From which data? All .img.sec file, or file without salt?

[arris69]

ok, i got 188 bytes public key in PEM format. Which of .vs, .cs, .cmac files are signatures?

i guess neither...

Or signature is in the end of .sec file?

yes

From which data? All .img.sec file, or file without salt?

from the decrypted *.img file

[user644]

Thanks. Testing this.
And what are .vs, cs, cmac files for each sec.img?