Very interesting, and something I'd never considered before.
Instead of going to the effort of making the function run in a constant time, might adding a small random delay before it returns also mitigate against this type of attack?
Instead of going to the effort of making the function run in a constant time, might adding a small random delay before it returns also mitigate against this type of attack?
Noise technically mitigates, but it's like covering your unlocked safe with a cardboard box.