use correct amount of M-R tests in dsa_make_params()

This commit is contained in:
Steffen Jaeckel 2017-06-14 16:57:27 +02:00
parent 7453eddae9
commit 26b57032e7

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@ -75,11 +75,23 @@ static int dsa_make_params(prng_state *prng, int wprng, int group_size, int modu
L = modulus_size * 8; L = modulus_size * 8;
N = group_size * 8; N = group_size * 8;
/* XXX-TODO no Lucas test */
#ifdef LTC_MPI_HAS_LUCAS_TEST
/* M-R tests (when followed by one Lucas test) according FIPS-186-4 - Appendix C.3 - table C.1 */ /* M-R tests (when followed by one Lucas test) according FIPS-186-4 - Appendix C.3 - table C.1 */
mr_tests_p = (L <= 2048) ? 3 : 2; mr_tests_p = (L <= 2048) ? 3 : 2;
if (N <= 160) { mr_tests_q = 19; } if (N <= 160) { mr_tests_q = 19; }
else if (N <= 224) { mr_tests_q = 24; } else if (N <= 224) { mr_tests_q = 24; }
else { mr_tests_q = 27; } else { mr_tests_q = 27; }
#else
/* M-R tests (without Lucas test) according FIPS-186-4 - Appendix C.3 - table C.1 */
if (L <= 1024) { mr_tests_p = 40; }
else if (L <= 2048) { mr_tests_p = 56; }
else { mr_tests_p = 64; }
if (N <= 160) { mr_tests_q = 40; }
else if (N <= 224) { mr_tests_q = 56; }
else { mr_tests_q = 64; }
#endif
if (N <= 256) { if (N <= 256) {
hash = register_hash(&sha256_desc); hash = register_hash(&sha256_desc);
@ -122,7 +134,7 @@ static int dsa_make_params(prng_state *prng, int wprng, int group_size, int modu
if ((err = mp_mod(U, t2N1, U)) != CRYPT_OK) { goto cleanup; } if ((err = mp_mod(U, t2N1, U)) != CRYPT_OK) { goto cleanup; }
if ((err = mp_add(t2N1, U, q)) != CRYPT_OK) { goto cleanup; } if ((err = mp_add(t2N1, U, q)) != CRYPT_OK) { goto cleanup; }
if (!mp_isodd(q)) mp_add_d(q, 1, q); if (!mp_isodd(q)) mp_add_d(q, 1, q);
if ((err = mp_prime_is_prime(q, mr_tests_q, &res)) != CRYPT_OK) { goto cleanup; } /* XXX-TODO rounds are ignored; no Lucas test */ if ((err = mp_prime_is_prime(q, mr_tests_q, &res)) != CRYPT_OK) { goto cleanup; }
if (res == LTC_MP_YES) found_q = 1; if (res == LTC_MP_YES) found_q = 1;
} }
@ -149,7 +161,7 @@ static int dsa_make_params(prng_state *prng, int wprng, int group_size, int modu
if ((err = mp_sub(X, p, p)) != CRYPT_OK) { goto cleanup; } if ((err = mp_sub(X, p, p)) != CRYPT_OK) { goto cleanup; }
if (mp_cmp(p, t2L1) != LTC_MP_LT) { if (mp_cmp(p, t2L1) != LTC_MP_LT) {
/* p >= 2^(L-1) */ /* p >= 2^(L-1) */
if ((err = mp_prime_is_prime(p, mr_tests_p, &res)) != CRYPT_OK) { goto cleanup; } /* XXX-TODO rounds are ignored; no Lucas test */ if ((err = mp_prime_is_prime(p, mr_tests_p, &res)) != CRYPT_OK) { goto cleanup; }
if (res == LTC_MP_YES) { if (res == LTC_MP_YES) {
found_p = 1; found_p = 1;
} }