I am running a Zephyr OS, and I am using the mbedtls APIs to do my cryptographic operations using the Cryptocell as my backend. My question is should I be using a mutex of some sort around mbedtls API calls, or is that being done at a lower level. I am wondering if it is possible that a different thread that also uses the cryptocell could try to access it at the same time and cause an issue.
So for example on this set of functions should I implement a mutex to protect the Cryptocell from other threads doing similar function calls, or is that being handled for me. I can't see the source below this level, its just your library.
mbedtls_aes_context aes;
mbedtls_aes_init(&aes);
mbedtls_aes_setkey_enc(&aes, key, DB_KEY_SIZE * 8); // key size in bits
mbedtls_aes_crypt_ctr(&aes, crypt_size, &nc_off, iv, stream_block, input, output);
mbedtls_aes_free(&aes);
