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Diffstat (limited to 'tests/include/test/bignum_helpers.h')
| -rw-r--r-- | tests/include/test/bignum_helpers.h | 98 |
1 files changed, 98 insertions, 0 deletions
diff --git a/tests/include/test/bignum_helpers.h b/tests/include/test/bignum_helpers.h new file mode 100644 index 00000000000..a5e49cbe576 --- /dev/null +++ b/tests/include/test/bignum_helpers.h @@ -0,0 +1,98 @@ +/** + * \file bignum_helpers.h + * + * \brief This file contains the prototypes of helper functions for + * bignum-related testing. + */ + +/* + * Copyright The Mbed TLS Contributors + * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later + */ + +#ifndef TEST_BIGNUM_HELPERS_H +#define TEST_BIGNUM_HELPERS_H + +#include <mbedtls/build_info.h> + +#if defined(MBEDTLS_BIGNUM_C) + +#include <mbedtls/bignum.h> +#include <bignum_mod.h> + +/** Allocate and populate a core MPI from a test case argument. + * + * This function allocates exactly as many limbs as necessary to fit + * the length of the input. In other words, it preserves leading zeros. + * + * The limb array is allocated with mbedtls_calloc() and must later be + * freed with mbedtls_free(). + * + * \param[in,out] pX The address where a pointer to the allocated limb + * array will be stored. + * \c *pX must be null on entry. + * On exit, \c *pX is null on error or if the number + * of limbs is 0. + * \param[out] plimbs The address where the number of limbs will be stored. + * \param[in] input The test argument to read. + * It is interpreted as a hexadecimal representation + * of a non-negative integer. + * + * \return \c 0 on success, an \c MBEDTLS_ERR_MPI_xxx error code otherwise. + */ +int mbedtls_test_read_mpi_core(mbedtls_mpi_uint **pX, size_t *plimbs, + const char *input); + +/** Read a modulus from a hexadecimal string. + * + * This function allocates exactly as many limbs as necessary to fit + * the length of the input. In other words, it preserves leading zeros. + * + * The limb array is allocated with mbedtls_calloc() and must later be + * freed with mbedtls_free(). You can do that by calling + * mbedtls_test_mpi_mod_modulus_free_with_limbs(). + * + * \param[in,out] N A modulus structure. It must be initialized, but + * not set up. + * \param[in] s The null-terminated hexadecimal string to read from. + * \param int_rep The desired representation of residues. + * + * \return \c 0 on success, an \c MBEDTLS_ERR_MPI_xxx error code otherwise. + */ +int mbedtls_test_read_mpi_modulus(mbedtls_mpi_mod_modulus *N, + const char *s, + mbedtls_mpi_mod_rep_selector int_rep); + +/** Free a modulus and its limbs. + * + * \param[in] N A modulus structure such that there is no other + * reference to `N->p`. + */ +void mbedtls_test_mpi_mod_modulus_free_with_limbs(mbedtls_mpi_mod_modulus *N); + +/** Read an MPI from a hexadecimal string. + * + * Like mbedtls_mpi_read_string(), but with tighter guarantees around + * edge cases. + * + * - This function guarantees that if \p s begins with '-' then the sign + * bit of the result will be negative, even if the value is 0. + * When this function encounters such a "negative 0", it calls + * mbedtls_test_increment_case_uses_negative_0(). + * - The size of the result is exactly the minimum number of limbs needed to fit + * the digits in the input. In particular, this function constructs a bignum + * with 0 limbs for an empty string, and a bignum with leading 0 limbs if the + * string has sufficiently many leading 0 digits. This is important so that + * the "0 (null)" and "0 (1 limb)" and "leading zeros" test cases do what they + * claim. + * + * \param[out] X The MPI object to populate. It must be initialized. + * \param[in] s The null-terminated hexadecimal string to read from. + * + * \return \c 0 on success, an \c MBEDTLS_ERR_MPI_xxx error code otherwise. + */ +int mbedtls_test_read_mpi(mbedtls_mpi *X, const char *s); + +#endif /* MBEDTLS_BIGNUM_C */ + +#endif /* TEST_BIGNUM_HELPERS_H */ |