microcontrollers

The article compares the performance and memory requirements of AES-GCM and ChaCha20Poly1305 AED encryption solutions for typical 8/16/32-bit embedded low-end processors in the Internet of Things device with different approaches to providing tolerance to Timing Attacks and Simple Power Analysis Attacks. Particular attention is given to the low-level multiplication implementation in GF(2128) with constant execution time as a key GCM operation, since low-end processors do not have ready instructions for carry-less multiplication.

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.