godot/thirdparty/mbedtls/library/bignum_internal.h

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/**
* Low level bignum functions
*
* Copyright The Mbed TLS Contributors
* SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
*/
#ifndef MBEDTLS_BIGNUM_INTERNAL_H
#define MBEDTLS_BIGNUM_INTERNAL_H
#include "mbedtls/bignum.h"
/**
* \brief Calculate the square of the Montgomery constant. (Needed
* for conversion and operations in Montgomery form.)
*
* \param[out] X A pointer to the result of the calculation of
* the square of the Montgomery constant:
* 2^{2*n*biL} mod N.
* \param[in] N Little-endian presentation of the modulus, which must be odd.
*
* \return 0 if successful.
* \return #MBEDTLS_ERR_MPI_ALLOC_FAILED if there is not enough space
* to store the value of Montgomery constant squared.
* \return #MBEDTLS_ERR_MPI_DIVISION_BY_ZERO if \p N modulus is zero.
* \return #MBEDTLS_ERR_MPI_NEGATIVE_VALUE if \p N modulus is negative.
*/
int mbedtls_mpi_get_mont_r2_unsafe(mbedtls_mpi *X,
const mbedtls_mpi *N);
/**
* \brief Calculate initialisation value for fast Montgomery modular
* multiplication
*
* \param[in] N Little-endian presentation of the modulus. This must have
* at least one limb.
*
* \return The initialisation value for fast Montgomery modular multiplication
*/
mbedtls_mpi_uint mbedtls_mpi_montmul_init(const mbedtls_mpi_uint *N);
/** Montgomery multiplication: A = A * B * R^-1 mod N (HAC 14.36)
*
* \param[in,out] A One of the numbers to multiply.
* It must have at least as many limbs as N
* (A->n >= N->n), and any limbs beyond n are ignored.
* On successful completion, A contains the result of
* the multiplication A * B * R^-1 mod N where
* R = (2^ciL)^n.
* \param[in] B One of the numbers to multiply.
* It must be nonzero and must not have more limbs than N
* (B->n <= N->n).
* \param[in] N The modulo. N must be odd.
* \param mm The value calculated by
* `mbedtls_mpi_montg_init(&mm, N)`.
* This is -N^-1 mod 2^ciL.
* \param[in,out] T A bignum for temporary storage.
* It must be at least twice the limb size of N plus 2
* (T->n >= 2 * (N->n + 1)).
* Its initial content is unused and
* its final content is indeterminate.
* Note that unlike the usual convention in the library
* for `const mbedtls_mpi*`, the content of T can change.
*/
void mbedtls_mpi_montmul(mbedtls_mpi *A,
const mbedtls_mpi *B,
const mbedtls_mpi *N,
mbedtls_mpi_uint mm,
const mbedtls_mpi *T);
#endif /* MBEDTLS_BIGNUM_INTERNAL_H */