sboot.bin Signatures and public key - GSM-Forum

adfree · 04-06-2018, 23:29

Hello.

Need help to understand where public key is...

To decrypt RSA 2048 Signatures inside sboot.bin Bootloader.
Exynos stuff... for instance.

I am able to find 256 Byte "blocks"...

Maybe good old GT-I9300 as example...

Found via Google:
https://www.dfrws.org/sites/default/...teria_mode.pdf

http://hexdetective.********.de/2017...t-getting.html

Please help to increase my little brain...

Maybe any pub key is leaked from any device... if dump or decryption is so tough...

Thanx in advance.

Best Regards

adfree · 04-06-2018, 23:55

https://kp-cdn.samsungknox.com/bb910...1f727b9593.pdf

https://de.slideshare.net/SamsungBus...mmies-59043192

According to these Documents...
Maybe I am searching for known:

Code:

Samsung Secure Boot Key (SSBK)

Quote:

The SSBK is an asymmetric key pair used to
sign Samsung-approved executables of boot components. The private part the SSBK is
used by Samsung to sign the secondary and application bootloaders. The public part of
the SSBK is stored in hardware one-time programmable fuses at manufacture time in
the Samsung factory. The Secure Boot process uses this public key to verify whether
each boot component it loads is approved.

Best Regards

adfree · 03-02-2023, 02:40

In Samsung Leak are funny things like key.xml

Code:

<?xml version="1.0"?> <KeyPair> <Modulus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odulus> <PublicExponent>00010001</PublicExponent> <PrivateExponent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rivateExponent> </KeyPair>

I found Signature to decrypt...

Looks again like RSA 2048 key...

Teegris related...

Somebody have an good idea what we can do with this?

Thanx in advance.

Best Regards

04-06-2018, 23:29	#1 (permalink)
adfree No Life Poster Join Date: Dec 2006 Location: yes Posts: 774 Member: 420658 Status: Offline Thanks Meter: 211	sboot.bin Signatures and public key Hello. Need help to understand where public key is... To decrypt RSA 2048 Signatures inside sboot.bin Bootloader. Exynos stuff... for instance. I am able to find 256 Byte "blocks"... Maybe good old GT-I9300 as example... Found via Google: https://www.dfrws.org/sites/default/...teria_mode.pdf http://hexdetective.********.de/2017...t-getting.html Please help to increase my little brain... Maybe any pub key is leaked from any device... if dump or decryption is so tough... Thanx in advance. Best Regards