2015-10-27 11:25 AM
Hi,
I've just douwnloaded the software from this page : http://www.st.com/web/en/catalog/tools/FM147/CL1794/SC961/SS1743/LN1734/PF257935 Its release_notes file deals withAN4024 ''STM32 secure firmware upgrade (SFU)''
. But I can't find this document anywhere. Do anybody have it or can tell me where it can be found ? Regards Julien #an40242015-10-27 11:32 AM
Call and speak to your local ST sales rep or FAE.
2015-10-28 03:06 AM
Hi Julien,
As suggested by Clive1, please contact your local distributor or FAE to get the application note document.-Syrine-2015-10-28 04:09 AM
It's interesting though why it's not available to general public. Security through obscurity? If the method's security depends on the information in that document then the method is not secure, otherwise, why isn't the document available?
As for the case, it's really easy for somebody who understand cryptography to create secure firmware update functionality (with authentication) using asymmetric encryption like elliptic curves (for authentication and block cipher key encryption) and any decent block cipher like AES. But if you don't understand cryptography, you will make mistakes.2015-10-28 04:17 AM
It's more probably a business/control issue, or to meet regulatory requirements.