Secret keys protection method for microcontrollers, based on special hardware blocks using

2018;
: pp. 3 - 7
1
Lviv Polytechnic National University, Computer Engineering Department

The proposed article demonstrates how to protect some memory areas in STM microcontrollers, what could be used for secret cypher keys storing, by using special hardware block “Firewall”. This method provides access to predefined microcontroller’s memory areas form configured in “Firewall” address space and blocks access from another program memory space. Since, STM microcontrollers provides connection to external Flash and SRAM for address space expanding, memory protection with “Firewall” was investigated when unauthorized code from external memory tries to get access to protected memory areas.

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