lukechilds/lightning - lightning - Gitea: Git with a cup of tea

Author	SHA1	Message	Date
Rusty Russell	5e3e2f4e17	run-secret_eq_consttime: try harder. This will never be reliable under high load, without making it unable to detect real errors. But the test is useful because if we don't have this test we'll never notice if we break the const-timedness of our implementation. So, move the calloc out of the test loop (which seems to make it more reliable), and then after we've run it, check the 1-minute load average. Too high, we don't complain about results. It's not perfect, but it's better. Running 100 times (-O3) serially gave 100 successes with the following results: Constant: Within 5% 562-926(832.89+/-73)/1000 times Non-constant: More than 5% slower 860-990(956.35+/-26)/1000 times More importantly, if we swap the const and non-const tests, we get the expected 100 failures: Non-constant: Within 5% 14-79(41.17+/-14)/1000 times Constant: More than 5% slower 44-231(111.89+/-33)/1000 times Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>	5 years ago
Rusty Russell	f73ae3c198	test: make run-secret_eq_consttime more robust. This is more reliable under load now: shorten the times so it is likely to run in a single timeslice, and add a nanosleep so it's likely to be at the start of the timeslice. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>	5 years ago
Rusty Russell	664916e815	bitcoin/test: fix up constant time test for secret_eq. We check that memcmp isn't constant time, but that's only true under -O2 or above: __OPTIMIZE__ doesn't distinguish. So we need a finer-grained test. Also reduce verbosity by default. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>	6 years ago
Rusty Russell	8340d8c070	secret_eq: remove in favor of constant time variant. To be safe, we should never memcmp secrets. We don't do this currently outside tests, but we're about to. The tests to prove this as constant time are the tricky bit. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>	6 years ago