ARMmbed/mbedtls
1
0
Fork 0
mirror of https://github.com/ARMmbed/mbedtls.git synced 2025-10-18 17:43:06 +08:00
Code Issues Releases Wiki Activity

Improve testing of mbedtls_mpi_gcd() and mbedtls_mpi_inv_mod()

Browse Source 
Signed-off-by: Felix Conway <felix.conway@arm.com>
This commit is contained in:
Felix Conway
2025-07-24 15:25:00 +01:00
parent 8f4779c6fa
commit 9646537e94
3 changed files with 47 additions and 12 deletions
Download Patch File Download Diff File Expand all files Collapse all files

7
include/mbedtls/bignum.h
View File

@@ -988,10 +988,13 @@ int mbedtls_mpi_gcd(mbedtls_mpi *G, const mbedtls_mpi *A,
* \brief Compute the modular inverse: X = A^-1 mod N
*
* \param X The destination MPI. This must point to an initialized MPI.
* The value returned on success will be between [1, N-1].
* \param A The MPI to calculate the modular inverse of. This must point
* to an initialized MPI.
* to an initialized MPI. This value can be negative, in which
* case a positive answer will still be returned in \p X.
* \param N The base of the modular inversion. This must point to an
* initialized MPI.
* initialized MPI. If this points to the same MPI as \p X,
* then the value returned in \p X will be incorrect.
*
* \return \c 0 if successful.
* \return #MBEDTLS_ERR_MPI_ALLOC_FAILED if a memory allocation failed.

49
tests/suites/test_suite_bignum.function
View File

@@ -390,12 +390,23 @@ void mpi_gcd(char *input_X, char *input_Y,
mbedtls_mpi A, X, Y, Z;
mbedtls_mpi_init(&A); mbedtls_mpi_init(&X); mbedtls_mpi_init(&Y); mbedtls_mpi_init(&Z);
TEST_ASSERT(mbedtls_test_read_mpi(&X, input_X) == 0);
TEST_ASSERT(mbedtls_test_read_mpi(&Y, input_Y) == 0);
TEST_ASSERT(mbedtls_test_read_mpi(&A, input_A) == 0);
TEST_ASSERT(mbedtls_mpi_gcd(&Z, &X, &Y) == 0);
TEST_EQUAL(mbedtls_test_read_mpi(&X, input_X), 0);
TEST_EQUAL(mbedtls_test_read_mpi(&Y, input_Y), 0);
TEST_EQUAL(mbedtls_test_read_mpi(&A, input_A), 0);
TEST_EQUAL(mbedtls_mpi_gcd(&Z, &X, &Y), 0);
TEST_ASSERT(sign_is_valid(&Z));
TEST_ASSERT(mbedtls_mpi_cmp_mpi(&Z, &A) == 0);
TEST_EQUAL(mbedtls_mpi_cmp_mpi(&Z, &A), 0);
mbedtls_mpi *Z_alias_X = &X;
TEST_EQUAL(mbedtls_mpi_gcd(Z_alias_X, &X, &Y), 0);
TEST_ASSERT(sign_is_valid(Z_alias_X));
TEST_EQUAL(mbedtls_mpi_cmp_mpi(Z_alias_X, &A), 0);
mbedtls_mpi *Z_alias_Y = &Y;
TEST_EQUAL(mbedtls_mpi_gcd(Z_alias_Y, &X, &Y), 0);
TEST_ASSERT(sign_is_valid(Z_alias_Y));
TEST_EQUAL(mbedtls_mpi_cmp_mpi(Z_alias_Y, &A), 0);
exit:
mbedtls_mpi_free(&A); mbedtls_mpi_free(&X); mbedtls_mpi_free(&Y); mbedtls_mpi_free(&Z);
@@ -1134,14 +1145,32 @@ void mpi_inv_mod(char *input_X, char *input_Y,
int res;
mbedtls_mpi_init(&X); mbedtls_mpi_init(&Y); mbedtls_mpi_init(&Z); mbedtls_mpi_init(&A);
TEST_ASSERT(mbedtls_test_read_mpi(&X, input_X) == 0);
TEST_ASSERT(mbedtls_test_read_mpi(&Y, input_Y) == 0);
TEST_ASSERT(mbedtls_test_read_mpi(&A, input_A) == 0);
TEST_EQUAL(mbedtls_test_read_mpi(&X, input_X), 0);
TEST_EQUAL(mbedtls_test_read_mpi(&Y, input_Y), 0);
TEST_EQUAL(mbedtls_test_read_mpi(&A, input_A), 0);
res = mbedtls_mpi_inv_mod(&Z, &X, &Y);
TEST_ASSERT(res == div_result);
TEST_EQUAL(res, div_result);
if (res == 0) {
TEST_ASSERT(sign_is_valid(&Z));
TEST_ASSERT(mbedtls_mpi_cmp_mpi(&Z, &A) == 0);
TEST_EQUAL(mbedtls_mpi_cmp_mpi(&Z, &A), 0);
}
mbedtls_mpi *Z_alias_X = &X;
res = mbedtls_mpi_inv_mod(Z_alias_X, &X, &Y);
TEST_EQUAL(res, div_result);
if (res == 0) {
TEST_ASSERT(sign_is_valid(Z_alias_X));
TEST_EQUAL(mbedtls_mpi_cmp_mpi(Z_alias_X, &A), 0);
}
/* When Z is an alias of Y, the answer returned in Z is normally incorrect. */
mbedtls_mpi *Z_alias_Y = &Y;
res = mbedtls_mpi_inv_mod(Z_alias_Y, &X, &Y);
TEST_EQUAL(res, div_result);
if (res == 0) {
TEST_ASSERT(sign_is_valid(Z_alias_Y));
/* Testing if Z_alias_Y == &A is not useful as it is true sometimes, but is
often false. */
}
exit:

3
tests/suites/test_suite_bignum.misc.data
View File

@@ -1504,6 +1504,9 @@ mpi_gcd:"136154c5dee27c04d296c5e29a32ad9fb923d66f5ce20ecab875aff2a8de964e668cc3e
Test GCD: 0 < A = B
mpi_gcd:"109fe45714866e56fdd4ad9b6b686df27224afb7868cf4f0cbb794526932853cbf0beea61594166654d13cd9fe0d9da594a97ee20230f12fb5434de73fb4f8102725a01622b31b1ea42e3a265019039ac1df31869bd97930d792fb72cdaa971d8a8015af":"109fe45714866e56fdd4ad9b6b686df27224afb7868cf4f0cbb794526932853cbf0beea61594166654d13cd9fe0d9da594a97ee20230f12fb5434de73fb4f8102725a01622b31b1ea42e3a265019039ac1df31869bd97930d792fb72cdaa971d8a8015af":"109fe45714866e56fdd4ad9b6b686df27224afb7868cf4f0cbb794526932853cbf0beea61594166654d13cd9fe0d9da594a97ee20230f12fb5434de73fb4f8102725a01622b31b1ea42e3a265019039ac1df31869bd97930d792fb72cdaa971d8a8015af"
Test GCD: A = B < 0
mpi_gcd:"-9986dabb54d13cd9fe0d9da594a97e8372ab26ed98ff622b31b1ea42e3a265019039ac1df31869bd97930d792fb72cdaa971d8a8015af":"-9986dabb54d13cd9fe0d9da594a97e8372ab26ed98ff622b31b1ea42e3a265019039ac1df31869bd97930d792fb72cdaa971d8a8015af":"9986dabb54d13cd9fe0d9da594a97e8372ab26ed98ff622b31b1ea42e3a265019039ac1df31869bd97930d792fb72cdaa971d8a8015af"
Base test mbedtls_mpi_inv_mod #1
mpi_inv_mod:"3":"b":"4":0