trezor-firmware

Commit Graph

Author	SHA1	Message	Date
Saleem Rashid	b4eaf7dbaf	timer: Fix non-critical integer overflow (#129 ) Every 4294967295 milliseconds (2 ^ 32 - 1), system_millis will overflow. This means that every 49.71 days, system_millis will reset to zero. Comparisons like `system_millis < (system_millis + 1)` would fail if the latter had overflown and the former had not. This is non-critical because the worst case is that one second could be skipped or the screen could lock early. This poses no threat to the exponential backoff used for protection against brute force.	8 years ago
Saleem Rashid	0ec32a6146	timer: Replace screen timeout with SysTick This provides an incredibly accurate screen timeout and removes the superfluous screen timeout counter	8 years ago
Saleem Rashid	25b9bfd97b	timer: Use Cortex-M3 SysTick timers Removed `usbDelay(uint32_t cycles)`, added `usbSleep(uint32_t millis)` The same method signature could cause silent code breakage at runtime, as opposed to noisy code breakage at compile time which is the better kind.	8 years ago

Author

SHA1

Message

Date

Saleem Rashid

b4eaf7dbaf

timer: Fix non-critical integer overflow (#129 )

Every 4294967295 milliseconds (2 ^ 32 - 1), system_millis will overflow.
This means that every 49.71 days, system_millis will reset to zero.
Comparisons like `system_millis < (system_millis + 1)` would fail if the
latter had overflown and the former had not.

This is non-critical because the worst case is that one second could be
skipped or the screen could lock early.

This poses no threat to the exponential backoff used for protection
against brute force.

Saleem Rashid

0ec32a6146

timer: Replace screen timeout with SysTick

This provides an incredibly accurate screen timeout and removes the
superfluous screen timeout counter

Saleem Rashid

25b9bfd97b

timer: Use Cortex-M3 SysTick timers

Removed `usbDelay(uint32_t cycles)`, added `usbSleep(uint32_t millis)`

The same method signature could cause silent code breakage at runtime,
as opposed to noisy code breakage at compile time which is the better
kind.

3 Commits (1943d840e3a2ec531075dca1d82de3924a87166e)