AM2432: Encrypt and save private keys in flash

Andrea Politano

Part Number: AM2432

Hi,

I am using AM2432 with the Industrial SDK 11.00.00.08.

I’m receiving a private key and I need to store it securely in flash
I cannot save the value in flash without encrypting it, and I cannot use keys hardcoded in code.
How can I do this? Is there a value I can use that cannot be viewed externally by a possible attacker?

Thank you,

Best Regards,

Andrea

4 months ago

+1 Hong Guan64 4 months ago

TI__Guru* 76730 points

Here're some pointers on the security features in AM243x MCU+SDK package for your reference.
https://software-dl.ti.com/processor-industrial-sw/esd/ind_comms_sdk/am243x/11_00_00_08/mcu_plus_sdk/docs/api_guide_am243x/SECURE_BOOT.html
https://software-dl.ti.com/processor-industrial-sw/esd/ind_comms_sdk/am243x/11_00_00_08/mcu_plus_sdk/docs/api_guide_am243x/SECURITY_PAGE.html
Best,
-Hong

0 Andrea Politano 3 months ago in reply to Hong Guan64

Intellectual 310 points

Hello Hong,

thank you for your reply.

The first link was not useful to me because it talks about encrypting the firmware and not about a variable itself or the entire flash memory. However, from the second link, I took the example of AES CBC 128 via hardware.

Is there now a way to extract a unique secret value for each device produced to use as a key? At the moment, I have seen Get_SoC_UID from this answer, but I would need more than 256 bits for more encryptions.

Thank you,

Best Regards,

Andrea

+1 Hong Guan64 3 months ago in reply to Andrea Politano

TI__Guru* 76730 points

Hello Andrea,
Some pointers on the TIFS secure services for your reference.
- DKEK
https://software-dl.ti.com/tisci/esd/latest/6_topic_user_guides/dkek_management.html
- CSP
https://software-dl.ti.com/tisci/esd/latest/6_topic_user_guides/csp.html
Best,
-Hong

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AM2432: Encrypt and save private keys in flash