259 lines
9.3 KiB
C
259 lines
9.3 KiB
C
/**
|
|
* 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 or a modulus
|
|
* equivalent to \p m (in the sense that all their fields or memory pointed to by
|
|
* their fields hold the same value).
|
|
*
|
|
* \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 */
|
|
|
|
/* END MERGE SLOT 3 */
|
|
|
|
/* BEGIN MERGE SLOT 4 */
|
|
|
|
/* END MERGE SLOT 4 */
|
|
|
|
/* BEGIN MERGE SLOT 5 */
|
|
|
|
/* 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 r The address of the residue. It must have exactly the same
|
|
* number of limbs as the modulus \p m.
|
|
* \param m The address of the modulus.
|
|
* \param 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 side channels. If \p r is
|
|
* secret, the caller must ensure that \p buflen is at least
|
|
* (`m->bits`+7)/8.
|
|
*
|
|
* \param r The address of the residue. It must have as many limbs as
|
|
* the modulus \p m.
|
|
* \param m The address of the modulus associated with \r.
|
|
* \param 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.
|
|
*/
|
|
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 */
|