Backport 2.1: More robust timing tests #1223
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The POSIX/Unix implementation of mbedtls_set_alarm did not set the mbedtls_timing_alarmed flag when called with 0, which was inconsistent with what the documentation implied and with the Windows behavior.
mbedtls_timing_get_timer with reset=1 is called both to initialize a timer object and to reset an already-initialized object. In an initial call, the content of the data structure is indeterminate, so the code should not read from it. This could crash if signed overflows trap, for example. As a consequence, on reset, we can't return the previously elapsed time as was previously done on Windows. Return 0 as was done on Unix.
Print some not-very-nice-looking but helpful diagnosis information if the timing selftest fails. Since the failures tend to be due to heavy system load that's hard to reproduce, this information is necessary to understand what's going on.
No behavior change.
If given command line arguments, interpret them as test names and only run those tests.
E.g. "selftest -x timing" runs all the self-tests except timing.
mbedtls_timing_self_test fails annoyingly often when running on a busy machine such as can be expected of a continous integration system. Increase the tolerances in the delay test, to reduce the chance of failures that are only due to missing a deadline on a busy machine.
Increase the duration of the self test, otherwise it tends to fail on a busy machine even with the recently upped tolerance. But run the loop only once, it's enough for a simple smoke test.
We don't need to test multiple delays in a self-test. Save 5s of busy-wait.
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mpg
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Dec 21, 2017
mpg
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Dec 21, 2017
Include stdlib.h for EXIT_FAILURE.
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@mpg In the development branch, there's |
mpg
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This is a partial backport of #1136 . Included:
mbedtls_timing_get_timeron Windows (internal ref: IOTSSL-1822)mbedtls_set_alarm(0)on Unix/POSIX.selftestprogram, support running a subset of the tests with command line arguments.Not included:
Internal ref: IOTSSL-1798