Test of uniformity of BN_rand_range output. (5d2f3e4a) · Commits · CYBER - Cyber Security / TS 103 523 MSP / TLMSP / TLMSP OpenSSL

INSTALL

+5 −0

Original line number	Diff line number	Diff line
		@@ -1200,6 +1200,11 @@

		$ make TESTS='[89]? -90'

		To stochastically verify that the algorithm that produces uniformly distributed
		random numbers is operating correctly (with a false positive rate of 0.01%):

		$ ./util/shlib_wrap.sh test/bntest -stochastic

		Note on multi-threading
		-----------------------

test/bn_rand_range.h

0 → 100644

+58 −0

Original line number	Diff line number	Diff line
		/*
		* WARNING: do not edit!
		* Generated by statistics/bn_rand_range.py in the OpenSSL tool repository.
		*
		* Copyright 2019 The OpenSSL Project Authors. All Rights Reserved.
		*
		* Licensed under the Apache License 2.0 (the "License"). You may not use
		* this file except in compliance with the License. You can obtain a copy
		* in the file LICENSE in the source distribution or at
		* https://www.openssl.org/source/license.html
		*/

		static const struct {
		unsigned int range;
		unsigned int iterations;
		double critical;
		} rand_range_cases[] = {
		{ 2, 200, 3.841459 },
		{ 3, 300, 5.991465 },
		{ 4, 400, 7.814728 },
		{ 5, 500, 9.487729 },
		{ 6, 600, 11.070498 },
		{ 7, 700, 12.591587 },
		{ 8, 800, 14.067140 },
		{ 9, 900, 15.507313 },
		{ 10, 1000, 16.918978 },
		{ 11, 1100, 18.307038 },
		{ 12, 1200, 19.675138 },
		{ 13, 1300, 21.026070 },
		{ 14, 1400, 22.362032 },
		{ 15, 1500, 23.684791 },
		{ 16, 1600, 24.995790 },
		{ 17, 1700, 26.296228 },
		{ 18, 1800, 27.587112 },
		{ 19, 1900, 28.869299 },
		{ 20, 2000, 30.143527 },
		{ 30, 3000, 42.556968 },
		{ 40, 4000, 54.572228 },
		{ 50, 5000, 66.338649 },
		{ 60, 6000, 77.930524 },
		{ 70, 7000, 89.391208 },
		{ 80, 8000, 100.748619 },
		{ 90, 9000, 112.021986 },
		{ 100, 10000, 123.225221 },
		{ 1000, 10000, 1073.642651 },
		{ 2000, 20000, 2104.128222 },
		{ 3000, 30000, 3127.515432 },
		{ 4000, 40000, 4147.230012 },
		{ 5000, 50000, 5164.598069 },
		{ 6000, 60000, 6180.299514 },
		{ 7000, 70000, 7194.738181 },
		{ 8000, 80000, 8208.177159 },
		{ 9000, 90000, 9220.799176 },
		{ 10000, 100000, 10232.737266 },
		};

		static const int binomial_critical = 29;

test/bntest.c

+60 −24

Original line number	Diff line number	Diff line
		@@ -1956,25 +1956,27 @@ static int test_rand(void)

		/*
		* Run some statistical tests to provide a degree confidence that the
		* BN_rand_range() function works as expected. The critical value
		* is computed using the R statistical suite:
		* BN_rand_range() function works as expected. The test cases and
		* critical values are generated by the bn_rand_range script.
		*
		* qchisq(alpha, df=iterations - 1)
		* Each individual test is a Chi^2 goodness of fit for a specified number
		* of samples and range. The samples are assumed to be independent and
		* that they are from a discrete uniform distribution.
		*
		* where alpha is the significance level (0.95 is used here) and iterations
		* is the number of samples being drawn.
		* Some of these individual tests are expected to fail, the success/failure
		* of each is an independent Bernoulli trial. The number of such successes
		* will form a binomial distribution. The count of the successes is compared
		* against a precomputed critical value to determine the overall outcome.
		*/
		static const struct {
		struct rand_range_case {
		unsigned int range;
		unsigned int iterations;
		double critical;
		} rand_range_cases[] = {
		{ 2, 100, 123.2252 /* = qchisq(.95, df=99) */ },
		{ 12, 1000, 1073.643 /* = qchisq(.95, df=999) */ },
		{ 1023, 100000, 100735.7 /* = qchisq(.95, df=99999) */ },
		};

		static int test_rand_range(int n)
		#include "bn_rand_range.h"

		static int test_rand_range_single(size_t n)
		{
		const unsigned int range = rand_range_cases[n].range;
		const unsigned int iterations = rand_range_cases[n].iterations;
		@@ -1998,21 +2000,19 @@ static int test_rand_range(int n)
		counts[v]++;
		}

		TEST_note("range %u iterations %u critical %.4f", range, iterations,
		critical);
		if (range < 20) {
		TEST_note("frequencies (expected %.2f)", expected);
		for (i = 0; i < range; i++)
		TEST_note(" %2u %6zu", i, counts[i]);
		}
		for (i = 0; i < range; i++) {
		const double delta = counts[i] - expected;
		sum += delta * delta;
		}
		sum /= expected;
		TEST_note("test statistic %.4f", sum);

		if (TEST_double_lt(sum, critical))
		if (sum > critical) {
		TEST_info("Chi^2 test negative %.4f > %4.f", sum, critical);
		TEST_note("test case %zu range %u iterations %u", n + 1, range,
		iterations);
		goto err;
		}

		res = 1;
		err:
		BN_free(rng);
		@@ -2021,6 +2021,19 @@ err:
		return res;
		}

		static int test_rand_range(void)
		{
		int n_success = 0;
		size_t i;

		for (i = 0; i < OSSL_NELEM(rand_range_cases); i++)
		n_success += test_rand_range_single(i);
		if (TEST_int_ge(n_success, binomial_critical))
		return 1;
		TEST_note("This test is expeced to fail by chance 0.01%% of the time.");
		return 0;
		}

		static int test_negzero(void)
		{
		BIGNUM a = NULL, b = NULL, c = NULL, d = NULL;
		@@ -2448,11 +2461,18 @@ static int run_file_tests(int i)
		return c == 0;
		}

		typedef enum OPTION_choice {
		OPT_ERR = -1,
		OPT_EOF = 0,
		OPT_STOCHASTIC_TESTS,
		OPT_TEST_ENUM
		} OPTION_CHOICE;

		const OPTIONS *test_get_options(void)
		{
		enum { OPT_TEST_ENUM };
		static const OPTIONS test_options[] = {
		OPT_TEST_OPTIONS_WITH_EXTRA_USAGE("[file...]\n"),
		{ "stochastic", OPT_STOCHASTIC_TESTS, '-', "Run stochastic tests" },
		{ OPT_HELP_STR, 1, '-',
		"file\tFile to run tests on. Normal tests are not run\n" },
		{ NULL }
		@@ -2462,7 +2482,22 @@ const OPTIONS *test_get_options(void)

		int setup_tests(void)
		{
		int n = test_get_argument_count();
		OPTION_CHOICE o;
		int n, stochastic = 0;

		while ((o = opt_next()) != OPT_EOF) {
		switch (o) {
		case OPT_STOCHASTIC_TESTS:
		stochastic = 1;
		break;
		case OPT_TEST_CASES:
		break;
		default:
		case OPT_ERR:
		return 0;
		}
		}
		n = test_get_argument_count();

		if (!TEST_ptr(ctx = BN_CTX_new()))
		return 0;
		@@ -2499,7 +2534,8 @@ int setup_tests(void)
		#endif
		ADD_ALL_TESTS(test_is_prime, (int)OSSL_NELEM(primes));
		ADD_ALL_TESTS(test_not_prime, (int)OSSL_NELEM(not_primes));
		ADD_ALL_TESTS(test_rand_range, OSSL_NELEM(rand_range_cases));
		if (stochastic)
		ADD_TEST(test_rand_range);
		} else {
		ADD_ALL_TESTS(run_file_tests, n);
		}