| /** |
| * Modular bignum functions |
| * |
| * This module implements operations on integers modulo some fixed modulus. |
| */ |
| |
| /* |
| * Copyright The Mbed TLS Contributors |
| * SPDX-License-Identifier: Apache-2.0 |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); you may |
| * not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT |
| * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #ifndef MBEDTLS_BIGNUM_MOD_H |
| #define MBEDTLS_BIGNUM_MOD_H |
| |
| #include "common.h" |
| |
| #if defined(MBEDTLS_BIGNUM_C) |
| #include "mbedtls/bignum.h" |
| #endif |
| |
| /* Skip 1 as it is slightly easier to accidentally pass to functions. */ |
| typedef enum |
| { |
| MBEDTLS_MPI_MOD_REP_INVALID = 0, |
| MBEDTLS_MPI_MOD_REP_MONTGOMERY = 2, |
| MBEDTLS_MPI_MOD_REP_OPT_RED |
| } mbedtls_mpi_mod_rep_selector; |
| |
| /* Make mbedtls_mpi_mod_rep_selector and mbedtls_mpi_mod_ext_rep disjoint to |
| * make it easier to catch when they are accidentally swapped. */ |
| typedef enum |
| { |
| MBEDTLS_MPI_MOD_EXT_REP_INVALID = 0, |
| MBEDTLS_MPI_MOD_EXT_REP_LE = 8, |
| MBEDTLS_MPI_MOD_EXT_REP_BE |
| } mbedtls_mpi_mod_ext_rep; |
| |
| typedef struct |
| { |
| mbedtls_mpi_uint *p; |
| size_t limbs; |
| } mbedtls_mpi_mod_residue; |
| |
| typedef struct { |
| mbedtls_mpi_uint const *rr; /* The residue for 2^{2*n*biL} mod N */ |
| mbedtls_mpi_uint mm; /* Montgomery const for -N^{-1} mod 2^{ciL} */ |
| } mbedtls_mpi_mont_struct; |
| |
| typedef void *mbedtls_mpi_opt_red_struct; |
| |
| typedef struct { |
| const mbedtls_mpi_uint *p; |
| size_t limbs; // number of limbs |
| size_t bits; // bitlen of p |
| mbedtls_mpi_mod_rep_selector int_rep; // selector to signal the active member of the union |
| union rep |
| { |
| mbedtls_mpi_mont_struct mont; |
| mbedtls_mpi_opt_red_struct ored; |
| } rep; |
| } mbedtls_mpi_mod_modulus; |
| |
| /** Setup a residue structure. |
| * |
| * The residue will be set up with the buffer \p p and modulus \p m. |
| * |
| * The memory pointed to by \p p will be used by the resulting residue structure. |
| * The value at the pointed-to memory will be the initial value of \p r and must |
| * hold a value that is less than the modulus. This value will be used as-is |
| * and interpreted according to the value of the `m->int_rep` field. |
| * |
| * The modulus \p m will be the modulus associated with \p r. The residue \p r |
| * should only be used in operations where the modulus is \p m. |
| * |
| * \param[out] r The address of the residue to setup. |
| * \param[in] m The address of the modulus related to \p r. |
| * \param[in] p The address of the limb array containing the value of \p r. |
| * The memory pointed to by \p p will be used by \p r and must |
| * not be modified in any way until after |
| * mbedtls_mpi_mod_residue_release() is called. The data |
| * pointed to by \p p must be less than the modulus (the value |
| * pointed to by `m->p`) and already in the representation |
| * indicated by `m->int_rep`. |
| * \param p_limbs The number of limbs of \p p. Must be the same as the number |
| * of limbs in the modulus \p m. |
| * |
| * \return \c 0 if successful. |
| * \return #MBEDTLS_ERR_MPI_BAD_INPUT_DATA if \p p_limbs is less than the |
| * limbs in \p m or if \p p is not less than \p m. |
| */ |
| int mbedtls_mpi_mod_residue_setup( mbedtls_mpi_mod_residue *r, |
| const mbedtls_mpi_mod_modulus *m, |
| mbedtls_mpi_uint *p, |
| size_t p_limbs ); |
| |
| /** Unbind elements of a residue structure. |
| * |
| * This function removes the reference to the limb array that was passed to |
| * mbedtls_mpi_mod_residue_setup() to make it safe to free or use again. |
| * |
| * This function invalidates \p r and it must not be used until after |
| * mbedtls_mpi_mod_residue_setup() is called on it again. |
| * |
| * \param[out] r The address of residue to release. |
| */ |
| void mbedtls_mpi_mod_residue_release( mbedtls_mpi_mod_residue *r ); |
| |
| /** Initialize a modulus structure. |
| * |
| * \param[out] m The address of the modulus structure to initialize. |
| */ |
| void mbedtls_mpi_mod_modulus_init( mbedtls_mpi_mod_modulus *m ); |
| |
| /** Setup a modulus structure. |
| * |
| * \param[out] m The address of the modulus structure to populate. |
| * \param[in] p The address of the limb array storing the value of \p m. |
| * The memory pointed to by \p p will be used by \p m and must |
| * not be modified in any way until after |
| * mbedtls_mpi_mod_modulus_free() is called. |
| * \param p_limbs The number of limbs of \p p. |
| * \param int_rep The internal representation to be used for residues |
| * associated with \p m (see #mbedtls_mpi_mod_rep_selector). |
| * |
| * \return \c 0 if successful. |
| * \return #MBEDTLS_ERR_MPI_BAD_INPUT_DATA if \p int_rep is invalid. |
| */ |
| int mbedtls_mpi_mod_modulus_setup( mbedtls_mpi_mod_modulus *m, |
| const mbedtls_mpi_uint *p, |
| size_t p_limbs, |
| mbedtls_mpi_mod_rep_selector int_rep ); |
| |
| /** Free elements of a modulus structure. |
| * |
| * This function frees any memory allocated by mbedtls_mpi_mod_modulus_setup(). |
| * |
| * \warning This function does not free the limb array passed to |
| * mbedtls_mpi_mod_modulus_setup() only removes the reference to it, |
| * making it safe to free or to use it again. |
| * |
| * \param[in,out] m The address of the modulus structure to free. |
| */ |
| void mbedtls_mpi_mod_modulus_free( mbedtls_mpi_mod_modulus *m ); |
| |
| /* BEGIN MERGE SLOT 1 */ |
| |
| /* END MERGE SLOT 1 */ |
| |
| /* BEGIN MERGE SLOT 2 */ |
| |
| /* END MERGE SLOT 2 */ |
| |
| /* BEGIN MERGE SLOT 3 */ |
| /** |
| * \brief Perform a fixed-size modular subtraction. |
| * |
| * Calculate `A - B modulo N`. |
| * |
| * \p A, \p B and \p X must all have the same number of limbs as \p N. |
| * |
| * \p X may be aliased to \p A or \p B, or even both, but may not overlap |
| * either otherwise. |
| * |
| * \note This function does not check that \p A or \p B are in canonical |
| * form (that is, are < \p N) - that will have been done by |
| * mbedtls_mpi_mod_residue_setup(). |
| * |
| * \param[out] X The address of the result MPI. Must be initialized. |
| * Must have the same number of limbs as the modulus \p N. |
| * \param[in] A The address of the first MPI. |
| * \param[in] B The address of the second MPI. |
| * \param[in] N The address of the modulus. Used to perform a modulo |
| * operation on the result of the subtraction. |
| * |
| * \return \c 0 if successful. |
| * \return #MBEDTLS_ERR_MPI_BAD_INPUT_DATA if the given MPIs do not |
| * have the correct number of limbs. |
| */ |
| int mbedtls_mpi_mod_sub( mbedtls_mpi_mod_residue *X, |
| const mbedtls_mpi_mod_residue *A, |
| const mbedtls_mpi_mod_residue *B, |
| const mbedtls_mpi_mod_modulus *N ); |
| /* END MERGE SLOT 3 */ |
| |
| /* BEGIN MERGE SLOT 4 */ |
| |
| /* END MERGE SLOT 4 */ |
| |
| /* BEGIN MERGE SLOT 5 */ |
| /** |
| * \brief Perform a fixed-size modular addition. |
| * |
| * Calculate `A + B modulo N`. |
| * |
| * \p A, \p B and \p X must all have the same number of limbs as \p N. |
| * |
| * \p X may be aliased to \p A or \p B, or even both, but may not overlap |
| * either otherwise. |
| * |
| * \note This function does not check that \p A or \p B are in canonical |
| * form (that is, are < \p N) - that will have been done by |
| * mbedtls_mpi_mod_residue_setup(). |
| * |
| * \param[out] X The address of the result MPI. Must be initialized. |
| * Must have the same number of limbs as the modulus \p N. |
| * \param[in] A The address of the first MPI. |
| * \param[in] B The address of the second MPI. |
| * \param[in] N The address of the modulus. Used to perform a modulo |
| * operation on the result of the addition. |
| * |
| * \return \c 0 if successful. |
| * \return #MBEDTLS_ERR_MPI_BAD_INPUT_DATA if the given MPIs do not |
| * have the correct number of limbs. |
| */ |
| int mbedtls_mpi_mod_add( mbedtls_mpi_mod_residue *X, |
| const mbedtls_mpi_mod_residue *A, |
| const mbedtls_mpi_mod_residue *B, |
| const mbedtls_mpi_mod_modulus *N ); |
| /* END MERGE SLOT 5 */ |
| |
| /* BEGIN MERGE SLOT 6 */ |
| |
| /* END MERGE SLOT 6 */ |
| |
| /* BEGIN MERGE SLOT 7 */ |
| /** Read a residue from a byte buffer. |
| * |
| * The residue will be automatically converted to the internal representation |
| * based on the value of the `m->int_rep` field. |
| * |
| * The modulus \p m will be the modulus associated with \p r. The residue \p r |
| * should only be used in operations where the modulus is \p m or a modulus |
| * equivalent to \p m (in the sense that all their fields or memory pointed by |
| * their fields hold the same value). |
| * |
| * \param[out] r The address of the residue. It must have exactly the same |
| * number of limbs as the modulus \p m. |
| * \param[in] m The address of the modulus. |
| * \param[in] buf The input buffer to import from. |
| * \param buflen The length in bytes of \p buf. |
| * \param ext_rep The endianness of the number in the input buffer. |
| * |
| * \return \c 0 if successful. |
| * \return #MBEDTLS_ERR_MPI_BUFFER_TOO_SMALL if \p r isn't |
| * large enough to hold the value in \p buf. |
| * \return #MBEDTLS_ERR_MPI_BAD_INPUT_DATA if \p ext_rep |
| * is invalid or the value in the buffer is not less than \p m. |
| */ |
| int mbedtls_mpi_mod_read( mbedtls_mpi_mod_residue *r, |
| const mbedtls_mpi_mod_modulus *m, |
| const unsigned char *buf, |
| size_t buflen, |
| mbedtls_mpi_mod_ext_rep ext_rep ); |
| |
| /** Write a residue into a byte buffer. |
| * |
| * The modulus \p m must be the modulus associated with \p r (see |
| * mbedtls_mpi_mod_residue_setup() and mbedtls_mpi_mod_read()). |
| * |
| * The residue will be automatically converted from the internal representation |
| * based on the value of `m->int_rep` field. |
| * |
| * \warning If the buffer is smaller than `m->bits`, the number of |
| * leading zeroes is leaked through timing. If \p r is |
| * secret, the caller must ensure that \p buflen is at least |
| * (`m->bits`+7)/8. |
| * |
| * \param[in] r The address of the residue. It must have the same number of |
| * limbs as the modulus \p m. (\p r is an input parameter, but |
| * its value will be modified during execution and restored |
| * before the function returns.) |
| * \param[in] m The address of the modulus associated with \r. |
| * \param[out] buf The output buffer to export to. |
| * \param buflen The length in bytes of \p buf. |
| * \param ext_rep The endianness in which the number should be written into |
| * the output buffer. |
| * |
| * \return \c 0 if successful. |
| * \return #MBEDTLS_ERR_MPI_BUFFER_TOO_SMALL if \p buf isn't |
| * large enough to hold the value of \p r (without leading |
| * zeroes). |
| * \return #MBEDTLS_ERR_MPI_BAD_INPUT_DATA if \p ext_rep is invalid. |
| * \return #MBEDTLS_ERR_MPI_ALLOC_FAILED if couldn't allocate enough |
| * memory for conversion. Can occur only for moduli with |
| * MBEDTLS_MPI_MOD_REP_MONTGOMERY. |
| */ |
| int mbedtls_mpi_mod_write( const mbedtls_mpi_mod_residue *r, |
| const mbedtls_mpi_mod_modulus *m, |
| unsigned char *buf, |
| size_t buflen, |
| mbedtls_mpi_mod_ext_rep ext_rep ); |
| /* END MERGE SLOT 7 */ |
| |
| /* BEGIN MERGE SLOT 8 */ |
| |
| /* END MERGE SLOT 8 */ |
| |
| /* BEGIN MERGE SLOT 9 */ |
| |
| /* END MERGE SLOT 9 */ |
| |
| /* BEGIN MERGE SLOT 10 */ |
| |
| /* END MERGE SLOT 10 */ |
| |
| #endif /* MBEDTLS_BIGNUM_MOD_H */ |
