Hi Joel
Can I check which version of Mbed TLS you were running your tests on?
The original commit you pointed to (76749aea78) is quite old, and the current code issues a single mbedtls_platform_zeroize() call (since 4cb56f83cb).
(I just want to make sure we are looking at the same code)
Thanks
Tom ________________________________ From: joel.petersson--- via mbed-tls mbed-tls@lists.trustedfirmware.org Sent: 23 August 2022 09:53 To: mbed-tls@lists.trustedfirmware.org mbed-tls@lists.trustedfirmware.org Subject: [mbed-tls] Re: Adding option to disable the zeroisation of internal buffers
Hi Ronald! Thank you for the suggestions. I have run some tests and have some numbers for you.
Hashing 100kb with sha256 on cortex-m7 board: 1. Current performance on master branch: ~5.2 million cycles 2. Removing call to mbedtls_platform_zeroize in mbedtls_internal_sha256_process_c: ~2.7 million cycles 3. Only calling mbedtls_platform_zeroize on the last block (by passing another argument to mbedtls_internal_sha256_process_c) : ~2.9 million cycles
Turns out I overestimated the slowdown in my original post, as it is closer to 50% - but with your suggestion we are back to almost the same numbers as before. // Joel -- mbed-tls mailing list -- mbed-tls@lists.trustedfirmware.org To unsubscribe send an email to mbed-tls-leave@lists.trustedfirmware.org