From b584737232c30e2cfa689b83561aa0c4e3d8e1ed Mon Sep 17 00:00:00 2001 From: tb Date: Tue, 9 May 2023 05:39:24 +0000 Subject: [PATCH] Add regress coverage for -1 modulus as well. --- regress/lib/libcrypto/bn/bn_mod_exp.c | 63 ++++++++++++++++----------- 1 file changed, 38 insertions(+), 25 deletions(-) diff --git a/regress/lib/libcrypto/bn/bn_mod_exp.c b/regress/lib/libcrypto/bn/bn_mod_exp.c index c20ad724427..14e18839797 100644 --- a/regress/lib/libcrypto/bn/bn_mod_exp.c +++ b/regress/lib/libcrypto/bn/bn_mod_exp.c @@ -1,4 +1,4 @@ -/* $OpenBSD: bn_mod_exp.c,v 1.37 2023/04/25 17:17:21 tb Exp $ */ +/* $OpenBSD: bn_mod_exp.c,v 1.38 2023/05/09 05:39:24 tb Exp $ */ /* * Copyright (c) 2022,2023 Theo Buehler @@ -86,19 +86,21 @@ bn_print(const char *name, const BIGNUM *bn) } static void -print_zero_test_failure(const BIGNUM *got, const BIGNUM *a, const char *name) +print_zero_test_failure(const BIGNUM *got, const BIGNUM *a, const BIGNUM *m, + const char *name) { fprintf(stderr, "%s() zero test failed:\n", name); bn_print("a", a); + bn_print("m", m); bn_print("got", got); } static int -bn_mod_exp_zero_test(const struct mod_exp_test *test, BN_CTX *ctx, int use_random) +bn_mod_exp_zero_test(const struct mod_exp_test *test, BN_CTX *ctx, + int neg_modulus, int random_base) { - const BIGNUM *one; - BIGNUM *a, *p, *got; + BIGNUM *a, *m, *p, *got; int mod_exp_ret; int failed = 1; @@ -106,24 +108,29 @@ bn_mod_exp_zero_test(const struct mod_exp_test *test, BN_CTX *ctx, int use_rando if ((a = BN_CTX_get(ctx)) == NULL) errx(1, "BN_CTX_get"); + if ((m = BN_CTX_get(ctx)) == NULL) + errx(1, "BN_CTX_get"); if ((p = BN_CTX_get(ctx)) == NULL) errx(1, "BN_CTX_get"); if ((got = BN_CTX_get(ctx)) == NULL) errx(1, "BN_CTX_get"); - one = BN_value_one(); + if (!BN_one(m)) + errx(1, "BN_one"); + if (neg_modulus) + BN_set_negative(m, 1); BN_zero(a); BN_zero(p); - if (use_random) { + if (random_base) { if (!BN_rand(a, 1024, BN_RAND_TOP_ANY, BN_RAND_BOTTOM_ANY)) errx(1, "BN_rand"); } if (test->mod_exp_fn != NULL) { - mod_exp_ret = test->mod_exp_fn(got, a, p, one, ctx); + mod_exp_ret = test->mod_exp_fn(got, a, p, m, ctx); } else { - mod_exp_ret = test->mod_exp_mont_fn(got, a, p, one, ctx, NULL); + mod_exp_ret = test->mod_exp_mont_fn(got, a, p, m, ctx, NULL); } if (!mod_exp_ret) { @@ -133,7 +140,7 @@ bn_mod_exp_zero_test(const struct mod_exp_test *test, BN_CTX *ctx, int use_rando } if (!BN_is_zero(got)) { - print_zero_test_failure(got, a, test->name); + print_zero_test_failure(got, a, m, test->name); goto err; } @@ -146,31 +153,35 @@ bn_mod_exp_zero_test(const struct mod_exp_test *test, BN_CTX *ctx, int use_rando } static int -bn_mod_exp_zero_word_test(BN_CTX *ctx) +bn_mod_exp_zero_word_test(BN_CTX *ctx, int neg_modulus) { const char *name = "BN_mod_exp_mont_word"; - const BIGNUM *one; - BIGNUM *p, *got; + BIGNUM *m, *p, *got; int failed = 1; BN_CTX_start(ctx); + if ((m = BN_CTX_get(ctx)) == NULL) + errx(1, "BN_CTX_get"); if ((p = BN_CTX_get(ctx)) == NULL) errx(1, "BN_CTX_get"); if ((got = BN_CTX_get(ctx)) == NULL) errx(1, "BN_CTX_get"); - one = BN_value_one(); + if (!BN_one(m)) + errx(1, "BN_one"); + if (neg_modulus) + BN_set_negative(m, neg_modulus); BN_zero(p); - if (!BN_mod_exp_mont_word(got, 1, p, one, ctx, NULL)) { + if (!BN_mod_exp_mont_word(got, 1, p, m, ctx, NULL)) { fprintf(stderr, "%s failed\n", name); ERR_print_errors_fp(stderr); goto err; } if (!BN_is_zero(got)) { - print_zero_test_failure(got, one, name); + print_zero_test_failure(got, p, m, name); goto err; } @@ -186,22 +197,24 @@ static int test_bn_mod_exp_zero(void) { BN_CTX *ctx; - size_t i; - int use_random; + size_t i, j; int failed = 0; if ((ctx = BN_CTX_new()) == NULL) errx(1, "BN_CTX_new"); - use_random = 1; - for (i = 0; i < N_MOD_EXP_FN; i++) - failed |= bn_mod_exp_zero_test(&mod_exp_fn[i], ctx, use_random); + for (i = 0; i < N_MOD_EXP_FN; i++) { + for (j = 0; j < 4; j++) { + int neg_modulus = (j >> 0) & 1; + int random_base = (j >> 1) & 1; - use_random = 0; - for (i = 0; i < N_MOD_EXP_FN; i++) - failed |= bn_mod_exp_zero_test(&mod_exp_fn[i], ctx, use_random); + failed |= bn_mod_exp_zero_test(&mod_exp_fn[i], ctx, + neg_modulus, random_base); + } + } - failed |= bn_mod_exp_zero_word_test(ctx); + failed |= bn_mod_exp_zero_word_test(ctx, 0); + failed |= bn_mod_exp_zero_word_test(ctx, 1); BN_CTX_free(ctx); -- 2.20.1