|  | /** | 
|  | * \file ecp_internal.h | 
|  | * | 
|  | * \brief Function declarations for alternative implementation of elliptic curve | 
|  | * point arithmetic. | 
|  | */ | 
|  | /* | 
|  | *  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. | 
|  | */ | 
|  |  | 
|  | /* | 
|  | * References: | 
|  | * | 
|  | * [1] BERNSTEIN, Daniel J. Curve25519: new Diffie-Hellman speed records. | 
|  | *     <http://cr.yp.to/ecdh/curve25519-20060209.pdf> | 
|  | * | 
|  | * [2] CORON, Jean-S'ebastien. Resistance against differential power analysis | 
|  | *     for elliptic curve cryptosystems. In : Cryptographic Hardware and | 
|  | *     Embedded Systems. Springer Berlin Heidelberg, 1999. p. 292-302. | 
|  | *     <http://link.springer.com/chapter/10.1007/3-540-48059-5_25> | 
|  | * | 
|  | * [3] HEDABOU, Mustapha, PINEL, Pierre, et B'EN'ETEAU, Lucien. A comb method to | 
|  | *     render ECC resistant against Side Channel Attacks. IACR Cryptology | 
|  | *     ePrint Archive, 2004, vol. 2004, p. 342. | 
|  | *     <http://eprint.iacr.org/2004/342.pdf> | 
|  | * | 
|  | * [4] Certicom Research. SEC 2: Recommended Elliptic Curve Domain Parameters. | 
|  | *     <http://www.secg.org/sec2-v2.pdf> | 
|  | * | 
|  | * [5] HANKERSON, Darrel, MENEZES, Alfred J., VANSTONE, Scott. Guide to Elliptic | 
|  | *     Curve Cryptography. | 
|  | * | 
|  | * [6] Digital Signature Standard (DSS), FIPS 186-4. | 
|  | *     <http://nvlpubs.nist.gov/nistpubs/FIPS/NIST.FIPS.186-4.pdf> | 
|  | * | 
|  | * [7] Elliptic Curve Cryptography (ECC) Cipher Suites for Transport Layer | 
|  | *     Security (TLS), RFC 4492. | 
|  | *     <https://tools.ietf.org/search/rfc4492> | 
|  | * | 
|  | * [8] <http://www.hyperelliptic.org/EFD/g1p/auto-shortw-jacobian.html> | 
|  | * | 
|  | * [9] COHEN, Henri. A Course in Computational Algebraic Number Theory. | 
|  | *     Springer Science & Business Media, 1 Aug 2000 | 
|  | */ | 
|  |  | 
|  | #ifndef MBEDTLS_ECP_INTERNAL_H | 
|  | #define MBEDTLS_ECP_INTERNAL_H | 
|  |  | 
|  | #if !defined(MBEDTLS_CONFIG_FILE) | 
|  | #include "mbedtls/config.h" | 
|  | #else | 
|  | #include MBEDTLS_CONFIG_FILE | 
|  | #endif | 
|  |  | 
|  | #if defined(MBEDTLS_ECP_INTERNAL_ALT) | 
|  |  | 
|  | /** | 
|  | * \brief           Indicate if the Elliptic Curve Point module extension can | 
|  | *                  handle the group. | 
|  | * | 
|  | * \param grp       The pointer to the elliptic curve group that will be the | 
|  | *                  basis of the cryptographic computations. | 
|  | * | 
|  | * \return          Non-zero if successful. | 
|  | */ | 
|  | unsigned char mbedtls_internal_ecp_grp_capable( const mbedtls_ecp_group *grp ); | 
|  |  | 
|  | /** | 
|  | * \brief           Initialise the Elliptic Curve Point module extension. | 
|  | * | 
|  | *                  If mbedtls_internal_ecp_grp_capable returns true for a | 
|  | *                  group, this function has to be able to initialise the | 
|  | *                  module for it. | 
|  | * | 
|  | *                  This module can be a driver to a crypto hardware | 
|  | *                  accelerator, for which this could be an initialise function. | 
|  | * | 
|  | * \param grp       The pointer to the group the module needs to be | 
|  | *                  initialised for. | 
|  | * | 
|  | * \return          0 if successful. | 
|  | */ | 
|  | int mbedtls_internal_ecp_init( const mbedtls_ecp_group *grp ); | 
|  |  | 
|  | /** | 
|  | * \brief           Frees and deallocates the Elliptic Curve Point module | 
|  | *                  extension. | 
|  | * | 
|  | * \param grp       The pointer to the group the module was initialised for. | 
|  | */ | 
|  | void mbedtls_internal_ecp_free( const mbedtls_ecp_group *grp ); | 
|  |  | 
|  | #if defined(MBEDTLS_ECP_SHORT_WEIERSTRASS_ENABLED) | 
|  |  | 
|  | #if defined(MBEDTLS_ECP_RANDOMIZE_JAC_ALT) | 
|  | /** | 
|  | * \brief           Randomize jacobian coordinates: | 
|  | *                  (X, Y, Z) -> (l^2 X, l^3 Y, l Z) for random l. | 
|  | * | 
|  | * \param grp       Pointer to the group representing the curve. | 
|  | * | 
|  | * \param pt        The point on the curve to be randomised, given with Jacobian | 
|  | *                  coordinates. | 
|  | * | 
|  | * \param f_rng     A function pointer to the random number generator. | 
|  | * | 
|  | * \param p_rng     A pointer to the random number generator state. | 
|  | * | 
|  | * \return          0 if successful. | 
|  | */ | 
|  | int mbedtls_internal_ecp_randomize_jac( const mbedtls_ecp_group *grp, | 
|  | mbedtls_ecp_point *pt, int (*f_rng)(void *, unsigned char *, size_t), | 
|  | void *p_rng ); | 
|  | #endif | 
|  |  | 
|  | #if defined(MBEDTLS_ECP_ADD_MIXED_ALT) | 
|  | /** | 
|  | * \brief           Addition: R = P + Q, mixed affine-Jacobian coordinates. | 
|  | * | 
|  | *                  The coordinates of Q must be normalized (= affine), | 
|  | *                  but those of P don't need to. R is not normalized. | 
|  | * | 
|  | *                  This function is used only as a subrutine of | 
|  | *                  ecp_mul_comb(). | 
|  | * | 
|  | *                  Special cases: (1) P or Q is zero, (2) R is zero, | 
|  | *                      (3) P == Q. | 
|  | *                  None of these cases can happen as intermediate step in | 
|  | *                  ecp_mul_comb(): | 
|  | *                      - at each step, P, Q and R are multiples of the base | 
|  | *                      point, the factor being less than its order, so none of | 
|  | *                      them is zero; | 
|  | *                      - Q is an odd multiple of the base point, P an even | 
|  | *                      multiple, due to the choice of precomputed points in the | 
|  | *                      modified comb method. | 
|  | *                  So branches for these cases do not leak secret information. | 
|  | * | 
|  | *                  We accept Q->Z being unset (saving memory in tables) as | 
|  | *                  meaning 1. | 
|  | * | 
|  | *                  Cost in field operations if done by [5] 3.22: | 
|  | *                      1A := 8M + 3S | 
|  | * | 
|  | * \param grp       Pointer to the group representing the curve. | 
|  | * | 
|  | * \param R         Pointer to a point structure to hold the result. | 
|  | * | 
|  | * \param P         Pointer to the first summand, given with Jacobian | 
|  | *                  coordinates | 
|  | * | 
|  | * \param Q         Pointer to the second summand, given with affine | 
|  | *                  coordinates. | 
|  | * | 
|  | * \return          0 if successful. | 
|  | */ | 
|  | int mbedtls_internal_ecp_add_mixed( const mbedtls_ecp_group *grp, | 
|  | mbedtls_ecp_point *R, const mbedtls_ecp_point *P, | 
|  | const mbedtls_ecp_point *Q ); | 
|  | #endif | 
|  |  | 
|  | /** | 
|  | * \brief           Point doubling R = 2 P, Jacobian coordinates. | 
|  | * | 
|  | *                  Cost:   1D := 3M + 4S    (A ==  0) | 
|  | *                          4M + 4S          (A == -3) | 
|  | *                          3M + 6S + 1a     otherwise | 
|  | *                  when the implementation is based on the "dbl-1998-cmo-2" | 
|  | *                  doubling formulas in [8] and standard optimizations are | 
|  | *                  applied when curve parameter A is one of { 0, -3 }. | 
|  | * | 
|  | * \param grp       Pointer to the group representing the curve. | 
|  | * | 
|  | * \param R         Pointer to a point structure to hold the result. | 
|  | * | 
|  | * \param P         Pointer to the point that has to be doubled, given with | 
|  | *                  Jacobian coordinates. | 
|  | * | 
|  | * \return          0 if successful. | 
|  | */ | 
|  | #if defined(MBEDTLS_ECP_DOUBLE_JAC_ALT) | 
|  | int mbedtls_internal_ecp_double_jac( const mbedtls_ecp_group *grp, | 
|  | mbedtls_ecp_point *R, const mbedtls_ecp_point *P ); | 
|  | #endif | 
|  |  | 
|  | /** | 
|  | * \brief           Normalize jacobian coordinates of an array of (pointers to) | 
|  | *                  points. | 
|  | * | 
|  | *                  Using Montgomery's trick to perform only one inversion mod P | 
|  | *                  the cost is: | 
|  | *                      1N(t) := 1I + (6t - 3)M + 1S | 
|  | *                  (See for example Algorithm 10.3.4. in [9]) | 
|  | * | 
|  | *                  This function is used only as a subrutine of | 
|  | *                  ecp_mul_comb(). | 
|  | * | 
|  | *                  Warning: fails (returning an error) if one of the points is | 
|  | *                  zero! | 
|  | *                  This should never happen, see choice of w in ecp_mul_comb(). | 
|  | * | 
|  | * \param grp       Pointer to the group representing the curve. | 
|  | * | 
|  | * \param T         Array of pointers to the points to normalise. | 
|  | * | 
|  | * \param t_len     Number of elements in the array. | 
|  | * | 
|  | * \return          0 if successful, | 
|  | *                      an error if one of the points is zero. | 
|  | */ | 
|  | #if defined(MBEDTLS_ECP_NORMALIZE_JAC_MANY_ALT) | 
|  | int mbedtls_internal_ecp_normalize_jac_many( const mbedtls_ecp_group *grp, | 
|  | mbedtls_ecp_point *T[], size_t t_len ); | 
|  | #endif | 
|  |  | 
|  | /** | 
|  | * \brief           Normalize jacobian coordinates so that Z == 0 || Z == 1. | 
|  | * | 
|  | *                  Cost in field operations if done by [5] 3.2.1: | 
|  | *                      1N := 1I + 3M + 1S | 
|  | * | 
|  | * \param grp       Pointer to the group representing the curve. | 
|  | * | 
|  | * \param pt        pointer to the point to be normalised. This is an | 
|  | *                  input/output parameter. | 
|  | * | 
|  | * \return          0 if successful. | 
|  | */ | 
|  | #if defined(MBEDTLS_ECP_NORMALIZE_JAC_ALT) | 
|  | int mbedtls_internal_ecp_normalize_jac( const mbedtls_ecp_group *grp, | 
|  | mbedtls_ecp_point *pt ); | 
|  | #endif | 
|  |  | 
|  | #endif /* MBEDTLS_ECP_SHORT_WEIERSTRASS_ENABLED */ | 
|  |  | 
|  | #if defined(MBEDTLS_ECP_MONTGOMERY_ENABLED) | 
|  |  | 
|  | #if defined(MBEDTLS_ECP_DOUBLE_ADD_MXZ_ALT) | 
|  | int mbedtls_internal_ecp_double_add_mxz( const mbedtls_ecp_group *grp, | 
|  | mbedtls_ecp_point *R, mbedtls_ecp_point *S, const mbedtls_ecp_point *P, | 
|  | const mbedtls_ecp_point *Q, const mbedtls_mpi *d ); | 
|  | #endif | 
|  |  | 
|  | /** | 
|  | * \brief           Randomize projective x/z coordinates: | 
|  | *                      (X, Z) -> (l X, l Z) for random l | 
|  | * | 
|  | * \param grp       pointer to the group representing the curve | 
|  | * | 
|  | * \param P         the point on the curve to be randomised given with | 
|  | *                  projective coordinates. This is an input/output parameter. | 
|  | * | 
|  | * \param f_rng     a function pointer to the random number generator | 
|  | * | 
|  | * \param p_rng     a pointer to the random number generator state | 
|  | * | 
|  | * \return          0 if successful | 
|  | */ | 
|  | #if defined(MBEDTLS_ECP_RANDOMIZE_MXZ_ALT) | 
|  | int mbedtls_internal_ecp_randomize_mxz( const mbedtls_ecp_group *grp, | 
|  | mbedtls_ecp_point *P, int (*f_rng)(void *, unsigned char *, size_t), | 
|  | void *p_rng ); | 
|  | #endif | 
|  |  | 
|  | /** | 
|  | * \brief           Normalize Montgomery x/z coordinates: X = X/Z, Z = 1. | 
|  | * | 
|  | * \param grp       pointer to the group representing the curve | 
|  | * | 
|  | * \param P         pointer to the point to be normalised. This is an | 
|  | *                  input/output parameter. | 
|  | * | 
|  | * \return          0 if successful | 
|  | */ | 
|  | #if defined(MBEDTLS_ECP_NORMALIZE_MXZ_ALT) | 
|  | int mbedtls_internal_ecp_normalize_mxz( const mbedtls_ecp_group *grp, | 
|  | mbedtls_ecp_point *P ); | 
|  | #endif | 
|  |  | 
|  | #endif /* MBEDTLS_ECP_MONTGOMERY_ENABLED */ | 
|  |  | 
|  | #endif /* MBEDTLS_ECP_INTERNAL_ALT */ | 
|  |  | 
|  | #endif /* ecp_internal.h */ | 
|  |  |