766 lines
30 KiB
C
Executable file
766 lines
30 KiB
C
Executable file
/**
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* \file ecp.h
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*
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* \brief This file provides an API for Elliptic Curves over GF(P) (ECP).
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*
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* The use of ECP in cryptography and TLS is defined in
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* <em>Standards for Efficient Cryptography Group (SECG): SEC1
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* Elliptic Curve Cryptography</em> and
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* <em>RFC-4492: Elliptic Curve Cryptography (ECC) Cipher Suites
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* for Transport Layer Security (TLS)</em>.
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*
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* <em>RFC-2409: The Internet Key Exchange (IKE)</em> defines ECP
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* group types.
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*
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*/
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/*
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* Copyright (C) 2006-2018, Arm Limited (or its affiliates), All Rights Reserved
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* SPDX-License-Identifier: GPL-2.0
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License along
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* with this program; if not, write to the Free Software Foundation, Inc.,
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* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
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*
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* This file is part of Mbed TLS (https://tls.mbed.org)
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*/
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#ifndef MBEDTLS_ECP_H
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#define MBEDTLS_ECP_H
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#include "bignum.h"
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/*
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* ECP error codes
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*/
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#define MBEDTLS_ERR_ECP_BAD_INPUT_DATA -0x4F80 /**< Bad input parameters to function. */
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#define MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL -0x4F00 /**< The buffer is too small to write to. */
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#define MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE -0x4E80 /**< The requested feature is not available, for example, the requested curve is not supported. */
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#define MBEDTLS_ERR_ECP_VERIFY_FAILED -0x4E00 /**< The signature is not valid. */
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#define MBEDTLS_ERR_ECP_ALLOC_FAILED -0x4D80 /**< Memory allocation failed. */
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#define MBEDTLS_ERR_ECP_RANDOM_FAILED -0x4D00 /**< Generation of random value, such as ephemeral key, failed. */
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#define MBEDTLS_ERR_ECP_INVALID_KEY -0x4C80 /**< Invalid private or public key. */
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#define MBEDTLS_ERR_ECP_SIG_LEN_MISMATCH -0x4C00 /**< The buffer contains a valid signature followed by more data. */
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#define MBEDTLS_ERR_ECP_HW_ACCEL_FAILED -0x4B80 /**< The ECP hardware accelerator failed. */
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#ifdef __cplusplus
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extern "C" {
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#endif
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/**
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* Domain-parameter identifiers: curve, subgroup, and generator.
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*
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* \note Only curves over prime fields are supported.
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*
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* \warning This library does not support validation of arbitrary domain
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* parameters. Therefore, only standardized domain parameters from trusted
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* sources should be used. See mbedtls_ecp_group_load().
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*/
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typedef enum
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{
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MBEDTLS_ECP_DP_NONE = 0, /*!< Curve not defined. */
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MBEDTLS_ECP_DP_SECP192R1, /*!< Domain parameters for the 192-bit curve defined by FIPS 186-4 and SEC1. */
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MBEDTLS_ECP_DP_SECP224R1, /*!< Domain parameters for the 224-bit curve defined by FIPS 186-4 and SEC1. */
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MBEDTLS_ECP_DP_SECP256R1, /*!< Domain parameters for the 256-bit curve defined by FIPS 186-4 and SEC1. */
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MBEDTLS_ECP_DP_SECP384R1, /*!< Domain parameters for the 384-bit curve defined by FIPS 186-4 and SEC1. */
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MBEDTLS_ECP_DP_SECP521R1, /*!< Domain parameters for the 521-bit curve defined by FIPS 186-4 and SEC1. */
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MBEDTLS_ECP_DP_BP256R1, /*!< Domain parameters for 256-bit Brainpool curve. */
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MBEDTLS_ECP_DP_BP384R1, /*!< Domain parameters for 384-bit Brainpool curve. */
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MBEDTLS_ECP_DP_BP512R1, /*!< Domain parameters for 512-bit Brainpool curve. */
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MBEDTLS_ECP_DP_CURVE25519, /*!< Domain parameters for Curve25519. */
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MBEDTLS_ECP_DP_SECP192K1, /*!< Domain parameters for 192-bit "Koblitz" curve. */
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MBEDTLS_ECP_DP_SECP224K1, /*!< Domain parameters for 224-bit "Koblitz" curve. */
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MBEDTLS_ECP_DP_SECP256K1, /*!< Domain parameters for 256-bit "Koblitz" curve. */
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MBEDTLS_ECP_DP_CURVE448, /*!< Domain parameters for Curve448. */
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} mbedtls_ecp_group_id;
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/**
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* The number of supported curves, plus one for #MBEDTLS_ECP_DP_NONE.
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*
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* \note Montgomery curves are currently excluded.
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*/
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#define MBEDTLS_ECP_DP_MAX 12
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/**
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* Curve information, for use by other modules.
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*/
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typedef struct
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{
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mbedtls_ecp_group_id grp_id; /*!< An internal identifier. */
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uint16_t tls_id; /*!< The TLS NamedCurve identifier. */
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uint16_t bit_size; /*!< The curve size in bits. */
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const char *name; /*!< A human-friendly name. */
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} mbedtls_ecp_curve_info;
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/**
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* \brief The ECP point structure, in Jacobian coordinates.
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*
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* \note All functions expect and return points satisfying
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* the following condition: <code>Z == 0</code> or
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* <code>Z == 1</code>. Other values of \p Z are
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* used only by internal functions.
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* The point is zero, or "at infinity", if <code>Z == 0</code>.
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* Otherwise, \p X and \p Y are its standard (affine)
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* coordinates.
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*/
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typedef struct
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{
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mbedtls_mpi X; /*!< The X coordinate of the ECP point. */
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mbedtls_mpi Y; /*!< The Y coordinate of the ECP point. */
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mbedtls_mpi Z; /*!< The Z coordinate of the ECP point. */
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}
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mbedtls_ecp_point;
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#if !defined(MBEDTLS_ECP_ALT)
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/*
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* default mbed TLS elliptic curve arithmetic implementation
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*
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* (in case MBEDTLS_ECP_ALT is defined then the developer has to provide an
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* alternative implementation for the whole module and it will replace this
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* one.)
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*/
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/**
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* \brief The ECP group structure.
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*
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* We consider two types of curve equations:
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* <ul><li>Short Weierstrass: <code>y^2 = x^3 + A x + B mod P</code>
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* (SEC1 + RFC-4492)</li>
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* <li>Montgomery: <code>y^2 = x^3 + A x^2 + x mod P</code> (Curve25519,
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* Curve448)</li></ul>
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* In both cases, the generator (\p G) for a prime-order subgroup is fixed.
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*
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* For Short Weierstrass, this subgroup is the whole curve, and its
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* cardinality is denoted by \p N. Our code requires that \p N is an
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* odd prime as mbedtls_ecp_mul() requires an odd number, and
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* mbedtls_ecdsa_sign() requires that it is prime for blinding purposes.
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*
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* For Montgomery curves, we do not store \p A, but <code>(A + 2) / 4</code>,
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* which is the quantity used in the formulas. Additionally, \p nbits is
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* not the size of \p N but the required size for private keys.
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*
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* If \p modp is NULL, reduction modulo \p P is done using a generic algorithm.
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* Otherwise, \p modp must point to a function that takes an \p mbedtls_mpi in the
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* range of <code>0..2^(2*pbits)-1</code>, and transforms it in-place to an integer
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* which is congruent mod \p P to the given MPI, and is close enough to \p pbits
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* in size, so that it may be efficiently brought in the 0..P-1 range by a few
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* additions or subtractions. Therefore, it is only an approximative modular
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* reduction. It must return 0 on success and non-zero on failure.
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*
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*/
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typedef struct
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{
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mbedtls_ecp_group_id id; /*!< An internal group identifier. */
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mbedtls_mpi P; /*!< The prime modulus of the base field. */
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mbedtls_mpi A; /*!< For Short Weierstrass: \p A in the equation. For
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Montgomery curves: <code>(A + 2) / 4</code>. */
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mbedtls_mpi B; /*!< For Short Weierstrass: \p B in the equation.
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For Montgomery curves: unused. */
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mbedtls_ecp_point G; /*!< The generator of the subgroup used. */
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mbedtls_mpi N; /*!< The order of \p G. */
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size_t pbits; /*!< The number of bits in \p P.*/
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size_t nbits; /*!< For Short Weierstrass: The number of bits in \p P.
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For Montgomery curves: the number of bits in the
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private keys. */
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unsigned int h; /*!< \internal 1 if the constants are static. */
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int (*modp)(mbedtls_mpi *); /*!< The function for fast pseudo-reduction
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mod \p P (see above).*/
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int (*t_pre)(mbedtls_ecp_point *, void *); /*!< Unused. */
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int (*t_post)(mbedtls_ecp_point *, void *); /*!< Unused. */
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void *t_data; /*!< Unused. */
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mbedtls_ecp_point *T; /*!< Pre-computed points for ecp_mul_comb(). */
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size_t T_size; /*!< The number of pre-computed points. */
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}
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mbedtls_ecp_group;
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/**
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* \name SECTION: Module settings
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*
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* The configuration options you can set for this module are in this section.
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* Either change them in config.h, or define them using the compiler command line.
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* \{
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*/
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#if !defined(MBEDTLS_ECP_MAX_BITS)
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/**
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* The maximum size of the groups, that is, of \c N and \c P.
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*/
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#define MBEDTLS_ECP_MAX_BITS 521 /**< The maximum size of groups, in bits. */
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#endif
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#define MBEDTLS_ECP_MAX_BYTES ( ( MBEDTLS_ECP_MAX_BITS + 7 ) / 8 )
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#define MBEDTLS_ECP_MAX_PT_LEN ( 2 * MBEDTLS_ECP_MAX_BYTES + 1 )
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#if !defined(MBEDTLS_ECP_WINDOW_SIZE)
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/*
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* Maximum "window" size used for point multiplication.
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* Default: 6.
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* Minimum value: 2. Maximum value: 7.
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*
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* Result is an array of at most ( 1 << ( MBEDTLS_ECP_WINDOW_SIZE - 1 ) )
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* points used for point multiplication. This value is directly tied to EC
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* peak memory usage, so decreasing it by one should roughly cut memory usage
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* by two (if large curves are in use).
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*
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* Reduction in size may reduce speed, but larger curves are impacted first.
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* Sample performances (in ECDHE handshakes/s, with FIXED_POINT_OPTIM = 1):
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* w-size: 6 5 4 3 2
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* 521 145 141 135 120 97
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* 384 214 209 198 177 146
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* 256 320 320 303 262 226
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* 224 475 475 453 398 342
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* 192 640 640 633 587 476
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*/
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#define MBEDTLS_ECP_WINDOW_SIZE 6 /**< The maximum window size used. */
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#endif /* MBEDTLS_ECP_WINDOW_SIZE */
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#if !defined(MBEDTLS_ECP_FIXED_POINT_OPTIM)
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/*
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* Trade memory for speed on fixed-point multiplication.
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*
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* This speeds up repeated multiplication of the generator (that is, the
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* multiplication in ECDSA signatures, and half of the multiplications in
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* ECDSA verification and ECDHE) by a factor roughly 3 to 4.
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*
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* The cost is increasing EC peak memory usage by a factor roughly 2.
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*
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* Change this value to 0 to reduce peak memory usage.
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*/
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#define MBEDTLS_ECP_FIXED_POINT_OPTIM 1 /**< Enable fixed-point speed-up. */
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#endif /* MBEDTLS_ECP_FIXED_POINT_OPTIM */
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/* \} name SECTION: Module settings */
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#else /* MBEDTLS_ECP_ALT */
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#include "ecp_alt.h"
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#endif /* MBEDTLS_ECP_ALT */
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/**
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* \brief The ECP key-pair structure.
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*
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* A generic key-pair that may be used for ECDSA and fixed ECDH, for example.
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*
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* \note Members are deliberately in the same order as in the
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* ::mbedtls_ecdsa_context structure.
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*/
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typedef struct
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{
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mbedtls_ecp_group grp; /*!< Elliptic curve and base point */
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mbedtls_mpi d; /*!< our secret value */
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mbedtls_ecp_point Q; /*!< our public value */
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}
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mbedtls_ecp_keypair;
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/*
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* Point formats, from RFC 4492's enum ECPointFormat
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*/
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#define MBEDTLS_ECP_PF_UNCOMPRESSED 0 /**< Uncompressed point format. */
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#define MBEDTLS_ECP_PF_COMPRESSED 1 /**< Compressed point format. */
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/*
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* Some other constants from RFC 4492
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*/
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#define MBEDTLS_ECP_TLS_NAMED_CURVE 3 /**< The named_curve of ECCurveType. */
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/**
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* \brief This function retrieves the information defined in
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* mbedtls_ecp_curve_info() for all supported curves in order
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* of preference.
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*
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* \return A statically allocated array. The last entry is 0.
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*/
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const mbedtls_ecp_curve_info *mbedtls_ecp_curve_list( void );
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/**
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* \brief This function retrieves the list of internal group
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* identifiers of all supported curves in the order of
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* preference.
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*
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* \return A statically allocated array,
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* terminated with MBEDTLS_ECP_DP_NONE.
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*/
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const mbedtls_ecp_group_id *mbedtls_ecp_grp_id_list( void );
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/**
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* \brief This function retrieves curve information from an internal
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* group identifier.
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*
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* \param grp_id An \c MBEDTLS_ECP_DP_XXX value.
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*
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* \return The associated curve information on success.
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* \return NULL on failure.
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*/
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const mbedtls_ecp_curve_info *mbedtls_ecp_curve_info_from_grp_id( mbedtls_ecp_group_id grp_id );
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/**
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* \brief This function retrieves curve information from a TLS
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* NamedCurve value.
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*
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* \param tls_id An \c MBEDTLS_ECP_DP_XXX value.
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*
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* \return The associated curve information on success.
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* \return NULL on failure.
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*/
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const mbedtls_ecp_curve_info *mbedtls_ecp_curve_info_from_tls_id( uint16_t tls_id );
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/**
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* \brief This function retrieves curve information from a
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* human-readable name.
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*
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* \param name The human-readable name.
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*
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* \return The associated curve information on success.
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* \return NULL on failure.
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*/
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const mbedtls_ecp_curve_info *mbedtls_ecp_curve_info_from_name( const char *name );
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/**
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* \brief This function initializes a point as zero.
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*
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* \param pt The point to initialize.
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*/
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void mbedtls_ecp_point_init( mbedtls_ecp_point *pt );
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/**
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* \brief This function initializes an ECP group context
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* without loading any domain parameters.
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*
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* \note After this function is called, domain parameters
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* for various ECP groups can be loaded through the
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* mbedtls_ecp_load() or mbedtls_ecp_tls_read_group()
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* functions.
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*/
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void mbedtls_ecp_group_init( mbedtls_ecp_group *grp );
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/**
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* \brief This function initializes a key pair as an invalid one.
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*
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* \param key The key pair to initialize.
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*/
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void mbedtls_ecp_keypair_init( mbedtls_ecp_keypair *key );
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/**
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* \brief This function frees the components of a point.
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*
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* \param pt The point to free.
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*/
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void mbedtls_ecp_point_free( mbedtls_ecp_point *pt );
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/**
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* \brief This function frees the components of an ECP group.
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* \param grp The group to free.
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*/
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void mbedtls_ecp_group_free( mbedtls_ecp_group *grp );
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/**
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* \brief This function frees the components of a key pair.
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* \param key The key pair to free.
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*/
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void mbedtls_ecp_keypair_free( mbedtls_ecp_keypair *key );
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/**
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* \brief This function copies the contents of point \p Q into
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* point \p P.
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*
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* \param P The destination point.
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* \param Q The source point.
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*
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* \return \c 0 on success.
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* \return #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure.
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*/
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int mbedtls_ecp_copy( mbedtls_ecp_point *P, const mbedtls_ecp_point *Q );
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/**
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* \brief This function copies the contents of group \p src into
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* group \p dst.
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*
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* \param dst The destination group.
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* \param src The source group.
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*
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* \return \c 0 on success.
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* \return #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure.
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*/
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int mbedtls_ecp_group_copy( mbedtls_ecp_group *dst, const mbedtls_ecp_group *src );
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/**
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* \brief This function sets a point to zero.
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*
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* \param pt The point to set.
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*
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* \return \c 0 on success.
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* \return #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure.
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*/
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int mbedtls_ecp_set_zero( mbedtls_ecp_point *pt );
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/**
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* \brief This function checks if a point is zero.
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*
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* \param pt The point to test.
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*
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* \return \c 1 if the point is zero.
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* \return \c 0 if the point is non-zero.
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*/
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int mbedtls_ecp_is_zero( mbedtls_ecp_point *pt );
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/**
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* \brief This function compares two points.
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*
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* \note This assumes that the points are normalized. Otherwise,
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* they may compare as "not equal" even if they are.
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*
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* \param P The first point to compare.
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* \param Q The second point to compare.
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*
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* \return \c 0 if the points are equal.
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* \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if the points are not equal.
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*/
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int mbedtls_ecp_point_cmp( const mbedtls_ecp_point *P,
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const mbedtls_ecp_point *Q );
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/**
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* \brief This function imports a non-zero point from two ASCII
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* strings.
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*
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* \param P The destination point.
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* \param radix The numeric base of the input.
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* \param x The first affine coordinate, as a null-terminated string.
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* \param y The second affine coordinate, as a null-terminated string.
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*
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* \return \c 0 on success.
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* \return An \c MBEDTLS_ERR_MPI_XXX error code on failure.
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*/
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int mbedtls_ecp_point_read_string( mbedtls_ecp_point *P, int radix,
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const char *x, const char *y );
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/**
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* \brief This function exports a point into unsigned binary data.
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*
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* \param grp The group to which the point should belong.
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* \param P The point to export.
|
|
* \param format The point format. Should be an \c MBEDTLS_ECP_PF_XXX macro.
|
|
* \param olen The length of the output.
|
|
* \param buf The output buffer.
|
|
* \param buflen The length of the output buffer.
|
|
*
|
|
* \return \c 0 on success.
|
|
* \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA
|
|
* or #MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL on failure.
|
|
*/
|
|
int mbedtls_ecp_point_write_binary( const mbedtls_ecp_group *grp, const mbedtls_ecp_point *P,
|
|
int format, size_t *olen,
|
|
unsigned char *buf, size_t buflen );
|
|
|
|
/**
|
|
* \brief This function imports a point from unsigned binary data.
|
|
*
|
|
* \note This function does not check that the point actually
|
|
* belongs to the given group, see mbedtls_ecp_check_pubkey()
|
|
* for that.
|
|
*
|
|
* \param grp The group to which the point should belong.
|
|
* \param P The point to import.
|
|
* \param buf The input buffer.
|
|
* \param ilen The length of the input.
|
|
*
|
|
* \return \c 0 on success.
|
|
* \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if input is invalid.
|
|
* \return #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure.
|
|
* \return #MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE if the point format
|
|
* is not implemented.
|
|
*
|
|
*/
|
|
int mbedtls_ecp_point_read_binary( const mbedtls_ecp_group *grp, mbedtls_ecp_point *P,
|
|
const unsigned char *buf, size_t ilen );
|
|
|
|
/**
|
|
* \brief This function imports a point from a TLS ECPoint record.
|
|
*
|
|
* \note On function return, \p buf is updated to point to immediately
|
|
* after the ECPoint record.
|
|
*
|
|
* \param grp The ECP group used.
|
|
* \param pt The destination point.
|
|
* \param buf The address of the pointer to the start of the input buffer.
|
|
* \param len The length of the buffer.
|
|
*
|
|
* \return \c 0 on success.
|
|
* \return An \c MBEDTLS_ERR_MPI_XXX error code on initialization failure.
|
|
* \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if input is invalid.
|
|
*/
|
|
int mbedtls_ecp_tls_read_point( const mbedtls_ecp_group *grp, mbedtls_ecp_point *pt,
|
|
const unsigned char **buf, size_t len );
|
|
|
|
/**
|
|
* \brief This function exports a point as a TLS ECPoint record.
|
|
*
|
|
* \param grp The ECP group used.
|
|
* \param pt The point format to export to. The point format is an
|
|
* \c MBEDTLS_ECP_PF_XXX constant.
|
|
* \param format The export format.
|
|
* \param olen The length of the data written.
|
|
* \param buf The buffer to write to.
|
|
* \param blen The length of the buffer.
|
|
*
|
|
* \return \c 0 on success.
|
|
* \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA or
|
|
* #MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL on failure.
|
|
*/
|
|
int mbedtls_ecp_tls_write_point( const mbedtls_ecp_group *grp, const mbedtls_ecp_point *pt,
|
|
int format, size_t *olen,
|
|
unsigned char *buf, size_t blen );
|
|
|
|
/**
|
|
* \brief This function sets a group using standardized domain parameters.
|
|
*
|
|
* \note The index should be a value of the NamedCurve enum,
|
|
* as defined in <em>RFC-4492: Elliptic Curve Cryptography
|
|
* (ECC) Cipher Suites for Transport Layer Security (TLS)</em>,
|
|
* usually in the form of an \c MBEDTLS_ECP_DP_XXX macro.
|
|
*
|
|
* \param grp The destination group.
|
|
* \param id The identifier of the domain parameter set to load.
|
|
*
|
|
* \return \c 0 on success,
|
|
* \return An \c MBEDTLS_ERR_MPI_XXX error code on initialization failure.
|
|
* \return #MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE for unkownn groups.
|
|
|
|
*/
|
|
int mbedtls_ecp_group_load( mbedtls_ecp_group *grp, mbedtls_ecp_group_id id );
|
|
|
|
/**
|
|
* \brief This function sets a group from a TLS ECParameters record.
|
|
*
|
|
* \note \p buf is updated to point right after the ECParameters record
|
|
* on exit.
|
|
*
|
|
* \param grp The destination group.
|
|
* \param buf The address of the pointer to the start of the input buffer.
|
|
* \param len The length of the buffer.
|
|
*
|
|
* \return \c 0 on success.
|
|
* \return An \c MBEDTLS_ERR_MPI_XXX error code on initialization failure.
|
|
* \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if input is invalid.
|
|
*/
|
|
int mbedtls_ecp_tls_read_group( mbedtls_ecp_group *grp, const unsigned char **buf, size_t len );
|
|
|
|
/**
|
|
* \brief This function writes the TLS ECParameters record for a group.
|
|
*
|
|
* \param grp The ECP group used.
|
|
* \param olen The number of Bytes written.
|
|
* \param buf The buffer to write to.
|
|
* \param blen The length of the buffer.
|
|
*
|
|
* \return \c 0 on success.
|
|
* \return #MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL on failure.
|
|
*/
|
|
int mbedtls_ecp_tls_write_group( const mbedtls_ecp_group *grp, size_t *olen,
|
|
unsigned char *buf, size_t blen );
|
|
|
|
/**
|
|
* \brief This function performs multiplication of a point by
|
|
* an integer: \p R = \p m * \p P.
|
|
*
|
|
* It is not thread-safe to use same group in multiple threads.
|
|
*
|
|
* \note To prevent timing attacks, this function
|
|
* executes the exact same sequence of base-field
|
|
* operations for any valid \p m. It avoids any if-branch or
|
|
* array index depending on the value of \p m.
|
|
*
|
|
* \note If \p f_rng is not NULL, it is used to randomize
|
|
* intermediate results to prevent potential timing attacks
|
|
* targeting these results. We recommend always providing
|
|
* a non-NULL \p f_rng. The overhead is negligible.
|
|
*
|
|
* \param grp The ECP group.
|
|
* \param R The destination point.
|
|
* \param m The integer by which to multiply.
|
|
* \param P The point to multiply.
|
|
* \param f_rng The RNG function.
|
|
* \param p_rng The RNG context.
|
|
*
|
|
* \return \c 0 on success.
|
|
* \return #MBEDTLS_ERR_ECP_INVALID_KEY if \p m is not a valid private
|
|
* key, or \p P is not a valid public key.
|
|
* \return #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure.
|
|
*/
|
|
int mbedtls_ecp_mul( mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
|
|
const mbedtls_mpi *m, const mbedtls_ecp_point *P,
|
|
int (*f_rng)(void *, unsigned char *, size_t), void *p_rng );
|
|
|
|
/**
|
|
* \brief This function performs multiplication and addition of two
|
|
* points by integers: \p R = \p m * \p P + \p n * \p Q
|
|
*
|
|
* It is not thread-safe to use same group in multiple threads.
|
|
*
|
|
* \note In contrast to mbedtls_ecp_mul(), this function does not
|
|
* guarantee a constant execution flow and timing.
|
|
*
|
|
* \param grp The ECP group.
|
|
* \param R The destination point.
|
|
* \param m The integer by which to multiply \p P.
|
|
* \param P The point to multiply by \p m.
|
|
* \param n The integer by which to multiply \p Q.
|
|
* \param Q The point to be multiplied by \p n.
|
|
*
|
|
* \return \c 0 on success.
|
|
* \return #MBEDTLS_ERR_ECP_INVALID_KEY if \p m or \p n are not
|
|
* valid private keys, or \p P or \p Q are not valid public
|
|
* keys.
|
|
* \return #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure.
|
|
*/
|
|
int mbedtls_ecp_muladd( mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
|
|
const mbedtls_mpi *m, const mbedtls_ecp_point *P,
|
|
const mbedtls_mpi *n, const mbedtls_ecp_point *Q );
|
|
|
|
/**
|
|
* \brief This function checks that a point is a valid public key
|
|
* on this curve.
|
|
*
|
|
* It only checks that the point is non-zero, has
|
|
* valid coordinates and lies on the curve. It does not verify
|
|
* that it is indeed a multiple of \p G. This additional
|
|
* check is computationally more expensive, is not required
|
|
* by standards, and should not be necessary if the group
|
|
* used has a small cofactor. In particular, it is useless for
|
|
* the NIST groups which all have a cofactor of 1.
|
|
*
|
|
* \note This function uses bare components rather than an
|
|
* ::mbedtls_ecp_keypair structure, to ease use with other
|
|
* structures, such as ::mbedtls_ecdh_context or
|
|
* ::mbedtls_ecdsa_context.
|
|
*
|
|
* \param grp The curve the point should lie on.
|
|
* \param pt The point to check.
|
|
*
|
|
* \return \c 0 if the point is a valid public key.
|
|
* \return #MBEDTLS_ERR_ECP_INVALID_KEY on failure.
|
|
*/
|
|
int mbedtls_ecp_check_pubkey( const mbedtls_ecp_group *grp, const mbedtls_ecp_point *pt );
|
|
|
|
/**
|
|
* \brief This function checks that an \p mbedtls_mpi is a valid private
|
|
* key for this curve.
|
|
*
|
|
* \note This function uses bare components rather than an
|
|
* ::mbedtls_ecp_keypair structure to ease use with other
|
|
* structures, such as ::mbedtls_ecdh_context or
|
|
* ::mbedtls_ecdsa_context.
|
|
*
|
|
* \param grp The group used.
|
|
* \param d The integer to check.
|
|
*
|
|
* \return \c 0 if the point is a valid private key.
|
|
* \return #MBEDTLS_ERR_ECP_INVALID_KEY on failure.
|
|
*/
|
|
int mbedtls_ecp_check_privkey( const mbedtls_ecp_group *grp, const mbedtls_mpi *d );
|
|
|
|
/**
|
|
* \brief This function generates a keypair with a configurable base
|
|
* point.
|
|
*
|
|
* \note This function uses bare components rather than an
|
|
* ::mbedtls_ecp_keypair structure to ease use with other
|
|
* structures, such as ::mbedtls_ecdh_context or
|
|
* ::mbedtls_ecdsa_context.
|
|
*
|
|
* \param grp The ECP group.
|
|
* \param G The chosen base point.
|
|
* \param d The destination MPI (secret part).
|
|
* \param Q The destination point (public part).
|
|
* \param f_rng The RNG function.
|
|
* \param p_rng The RNG context.
|
|
*
|
|
* \return \c 0 on success.
|
|
* \return An \c MBEDTLS_ERR_ECP_XXX or \c MBEDTLS_MPI_XXX error code
|
|
* on failure.
|
|
*/
|
|
int mbedtls_ecp_gen_keypair_base( mbedtls_ecp_group *grp,
|
|
const mbedtls_ecp_point *G,
|
|
mbedtls_mpi *d, mbedtls_ecp_point *Q,
|
|
int (*f_rng)(void *, unsigned char *, size_t),
|
|
void *p_rng );
|
|
|
|
/**
|
|
* \brief This function generates an ECP keypair.
|
|
*
|
|
* \note This function uses bare components rather than an
|
|
* ::mbedtls_ecp_keypair structure to ease use with other
|
|
* structures, such as ::mbedtls_ecdh_context or
|
|
* ::mbedtls_ecdsa_context.
|
|
*
|
|
* \param grp The ECP group.
|
|
* \param d The destination MPI (secret part).
|
|
* \param Q The destination point (public part).
|
|
* \param f_rng The RNG function.
|
|
* \param p_rng The RNG context.
|
|
*
|
|
* \return \c 0 on success.
|
|
* \return An \c MBEDTLS_ERR_ECP_XXX or \c MBEDTLS_MPI_XXX error code
|
|
* on failure.
|
|
*/
|
|
int mbedtls_ecp_gen_keypair( mbedtls_ecp_group *grp, mbedtls_mpi *d, mbedtls_ecp_point *Q,
|
|
int (*f_rng)(void *, unsigned char *, size_t),
|
|
void *p_rng );
|
|
|
|
/**
|
|
* \brief This function generates an ECP key.
|
|
*
|
|
* \param grp_id The ECP group identifier.
|
|
* \param key The destination key.
|
|
* \param f_rng The RNG function.
|
|
* \param p_rng The RNG context.
|
|
*
|
|
* \return \c 0 on success.
|
|
* \return An \c MBEDTLS_ERR_ECP_XXX or \c MBEDTLS_MPI_XXX error code
|
|
* on failure.
|
|
*/
|
|
int mbedtls_ecp_gen_key( mbedtls_ecp_group_id grp_id, mbedtls_ecp_keypair *key,
|
|
int (*f_rng)(void *, unsigned char *, size_t), void *p_rng );
|
|
|
|
/**
|
|
* \brief This function checks that the keypair objects
|
|
* \p pub and \p prv have the same group and the
|
|
* same public point, and that the private key in
|
|
* \p prv is consistent with the public key.
|
|
*
|
|
* \param pub The keypair structure holding the public key.
|
|
* If it contains a private key, that part is ignored.
|
|
* \param prv The keypair structure holding the full keypair.
|
|
*
|
|
* \return \c 0 on success, meaning that the keys are valid and match.
|
|
* \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if the keys are invalid or do not match.
|
|
* \return An \c MBEDTLS_ERR_ECP_XXX or an \c MBEDTLS_ERR_MPI_XXX
|
|
* error code on calculation failure.
|
|
*/
|
|
int mbedtls_ecp_check_pub_priv( const mbedtls_ecp_keypair *pub, const mbedtls_ecp_keypair *prv );
|
|
|
|
#if defined(MBEDTLS_SELF_TEST)
|
|
|
|
/**
|
|
* \brief The ECP checkup routine.
|
|
*
|
|
* \return \c 0 on success.
|
|
* \return \c 1 on failure.
|
|
*/
|
|
int mbedtls_ecp_self_test( int verbose );
|
|
|
|
#endif /* MBEDTLS_SELF_TEST */
|
|
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif
|
|
|
|
#endif /* ecp.h */
|