Remove Bias and clarify use of TRNG #6
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`build.yml` is directly from the action's example, except targeting release (not dev). https://github.com/marketplace/actions/build-flipper-application-package-fap
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Fixes #2
Tested and works.
Remove existing bias towards characters earlier in the allowed alphabet. This is done by dynamically determining the maximum integral multiple value in a
char, and excluding TRNG data that is outside the range.Avoids calls to
rand()because that is (normally) not cryptographically random.No new memory allocations are used.
Every call to
furi_hal_random_get()takes a semaphore and re-initializes the TRNG hardware. This is inefficient and slower than usingfuri_hal_random_fill_buf().Iteratively call
furi_hal_random_fill_buf()until the required password length is filled with valid (unbiased) characters.Overwrite password buffer when free'ing state. Again ... just good security hygiene.
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