Slow extraction and improvements to Minerva analysis

[GeorgePantelakis]

Bug Report

Problem description

In the analysis for the Minerva / bit size attack, the confidence intervals for each bit size are calculated twice. This makes the analysis twice as slow for no reason. Also, the nonce extraction takes a lot of time, but then one extraction doesn't depend on the other, it could be run in parallel on multiple CPU cores to speed up the process. Moreover, the individual k-size folder creation probably can be parallelized in analysis.

Expected behavior

The extraction and analysis could be much faster.

Include errors or backtraces

...
[i] Wilcoxon signed-rank test done in 10.5s
[i] Calculating confidence intervals of central tendencies
Done: 100.00%, elapsed:  6m 58.66s, speed: 14.78 bootstraps/s, avg speed: 11.94 bootstraps/s, remaining:  0.00s, ETA: 12:59:44 08-01-2024              
[i] Confidence intervals of central tendencies done in 4.2e+02s
Creating graphs for k size 519...
[i] Graphing confidence interval plots
Done: 100.00%, elapsed:  6m 52.65s, speed: 14.93 bootstraps/s, avg speed: 12.12 bootstraps/s, remaining:  0.00s, ETA: 13:06:39 08-01-2024          
[i] Confidence interval plots done in 4.14e+02s
...

Additional context

Add any other context about the problem here.

[tomato42]

The measurements-invert.csv should also be processed when the test-tls13-minerva.py is executed (the analysis.py should still probably process one file at a time)

[GeorgePantelakis]

Other optimizations possible:

• Calculate how many samples will produce around 1ns CI and analyze only them.
• More advance method of not dividing by 0 in analysis
• In analysis be able to provide the measurements file name

[tomato42]

The other thing that we probably should do, is create a report.txt, similar to what the regular analysis does, i.e. one that includes:

• average, max and min p-values for the sign test and Wilcoxon signed rank test
• result of the Skillings-Mack test
• statistics for the 10-or-so biggest k-values: the p-test for sign test and Wilcoxon signed rank test, the 5% and 45% trimmed means and their confidence intervals
• layperson explanation of the result (side-channel possible, side-channel confirmed, or side-channel unlikely)

In general it should be fairly small (fit in 80-100 columns by 15-20 rows)

[GeorgePantelakis]

All the bugs and new features mentioned in this issue were done.

[tomato42]

@GeorgePantelakis are we analysing measurements-invert.csv by default in the TLS script now?