670 lines
25 KiB
C
670 lines
25 KiB
C
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/**
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* \file ecp.h
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*
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* \brief Elliptic curves over GF(p)
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*
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* Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
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* SPDX-License-Identifier: Apache-2.0
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*
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* Licensed under the Apache License, Version 2.0 (the "License"); you may
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* not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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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 /**< Requested curve not available. */
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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 /**< Signature is valid but shorter than the user-supplied length. */
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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 parameters (curve, subgroup and generator) identifiers.
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*
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* 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 well-known 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,
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MBEDTLS_ECP_DP_SECP192R1, /*!< 192-bits NIST curve */
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MBEDTLS_ECP_DP_SECP224R1, /*!< 224-bits NIST curve */
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MBEDTLS_ECP_DP_SECP256R1, /*!< 256-bits NIST curve */
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MBEDTLS_ECP_DP_SECP384R1, /*!< 384-bits NIST curve */
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MBEDTLS_ECP_DP_SECP521R1, /*!< 521-bits NIST curve */
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MBEDTLS_ECP_DP_BP256R1, /*!< 256-bits Brainpool curve */
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MBEDTLS_ECP_DP_BP384R1, /*!< 384-bits Brainpool curve */
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MBEDTLS_ECP_DP_BP512R1, /*!< 512-bits Brainpool curve */
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MBEDTLS_ECP_DP_CURVE25519, /*!< Curve25519 */
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MBEDTLS_ECP_DP_SECP192K1, /*!< 192-bits "Koblitz" curve */
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MBEDTLS_ECP_DP_SECP224K1, /*!< 224-bits "Koblitz" curve */
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MBEDTLS_ECP_DP_SECP256K1, /*!< 256-bits "Koblitz" curve */
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} mbedtls_ecp_group_id;
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/**
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* Number of supported curves (plus one for NONE).
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*
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* (Montgomery curves excluded for now.)
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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; /*!< Internal identifier */
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uint16_t tls_id; /*!< TLS NamedCurve identifier */
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uint16_t bit_size; /*!< Curve size in bits */
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const char *name; /*!< Human-friendly name */
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} mbedtls_ecp_curve_info;
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/**
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* \brief ECP point structure (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: Z == 0 or Z == 1. (Other
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* values of Z are used by internal functions only.)
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* The point is zero, or "at infinity", if Z == 0.
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* Otherwise, X and Y are its standard (affine) coordinates.
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*/
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typedef struct
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{
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mbedtls_mpi X; /*!< the point's X coordinate */
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mbedtls_mpi Y; /*!< the point's Y coordinate */
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mbedtls_mpi Z; /*!< the point's Z coordinate */
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}
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mbedtls_ecp_point;
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/**
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* \brief ECP group structure
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*
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* We consider two types of curves equations:
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* 1. Short Weierstrass y^2 = x^3 + A x + B mod P (SEC1 + RFC 4492)
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* 2. Montgomery, y^2 = x^3 + A x^2 + x mod P (Curve25519 + draft)
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* In both cases, a generator G for a prime-order subgroup is fixed. In the
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* short weierstrass, this subgroup is actually the whole curve, and its
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* cardinal is denoted by N.
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*
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* In the case of Short Weierstrass curves, our code requires that N is an odd
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* prime. (Use odd in mbedtls_ecp_mul() and prime in mbedtls_ecdsa_sign() for blinding.)
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*
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* In the case of Montgomery curves, we don't store A but (A + 2) / 4 which is
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* the quantity actually used in the formulas. Also, nbits is not the size of N
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* but the required size for private keys.
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*
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* If modp is NULL, reduction modulo P is done using a generic algorithm.
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* Otherwise, it must point to a function that takes an mbedtls_mpi in the range
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* 0..2^(2*pbits)-1 and transforms it in-place in an integer of little more
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* than pbits, so that the integer may be efficiently brought in the 0..P-1
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* range by a few additions or substractions. It must return 0 on success and
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* non-zero on failure.
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*/
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typedef struct
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{
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mbedtls_ecp_group_id id; /*!< internal group identifier */
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mbedtls_mpi P; /*!< prime modulus of the base field */
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mbedtls_mpi A; /*!< 1. A in the equation, or 2. (A + 2) / 4 */
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mbedtls_mpi B; /*!< 1. B in the equation, or 2. unused */
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mbedtls_ecp_point G; /*!< generator of the (sub)group used */
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mbedtls_mpi N; /*!< 1. the order of G, or 2. unused */
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size_t pbits; /*!< number of bits in P */
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size_t nbits; /*!< number of bits in 1. P, or 2. private keys */
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unsigned int h; /*!< internal: 1 if the constants are static */
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int (*modp)(mbedtls_mpi *); /*!< function for fast reduction mod P */
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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; /*!< number for pre-computed points */
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}
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mbedtls_ecp_group;
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/**
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* \brief ECP key pair structure
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*
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* A generic key pair that could be used for ECDSA, fixed ECDH, etc.
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*
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* \note Members purposefully in the same order as struc mbedtls_ecdsa_context.
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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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* \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 on 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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* Maximum size of the groups (that is, of N and P)
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*/
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#define MBEDTLS_ECP_MAX_BITS 521 /**< Maximum bit size of groups */
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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 /**< 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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/*
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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 /**< ECCurveType's named_curve */
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/**
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* \brief Get the list of supported curves in order of preferrence
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* (full information)
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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 Get the list of supported curves in order of preferrence
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* (grp_id only)
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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 Get curve information from an internal group identifier
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*
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* \param grp_id A MBEDTLS_ECP_DP_XXX value
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*
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* \return The associated curve information or NULL
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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 Get curve information from a TLS NamedCurve value
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*
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* \param tls_id A MBEDTLS_ECP_DP_XXX value
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*
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* \return The associated curve information or NULL
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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 Get curve information from a human-readable name
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*
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* \param name The name
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*
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* \return The associated curve information or NULL
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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 Initialize a point (as zero)
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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 Initialize a group (to something meaningless)
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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 Initialize a key pair (as an invalid one)
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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 Free the components of a point
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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 Free the components of an ECP group
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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 Free the components of a key pair
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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 Copy the contents of point Q into P
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*
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* \param P Destination point
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* \param Q Source point
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*
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* \return 0 if successful,
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* MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed
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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 Copy the contents of a group object
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*
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* \param dst Destination group
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* \param src Source group
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*
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* \return 0 if successful,
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* MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed
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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 Set a point to zero
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*
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* \param pt Destination point
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*
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* \return 0 if successful,
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* MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed
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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 Tell if a point is zero
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*
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* \param pt Point to test
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*
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* \return 1 if point is zero, 0 otherwise
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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 Compare two points
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*
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* \note This assumes 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 First point to compare
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* \param Q Second point to compare
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*
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* \return 0 if the points are equal,
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* MBEDTLS_ERR_ECP_BAD_INPUT_DATA otherwise
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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 Import a non-zero point from two ASCII strings
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*
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* \param P Destination point
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* \param radix Input numeric base
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* \param x First affine coordinate as a null-terminated string
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* \param y Second affine coordinate as a null-terminated string
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*
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* \return 0 if successful, or a MBEDTLS_ERR_MPI_XXX error code
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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 Export a point into unsigned binary data
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*
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* \param grp Group to which the point should belong
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* \param P Point to export
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* \param format Point format, should be a MBEDTLS_ECP_PF_XXX macro
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* \param olen Length of the actual output
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* \param buf Output buffer
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* \param buflen Length of the output buffer
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*
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* \return 0 if successful,
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* or MBEDTLS_ERR_ECP_BAD_INPUT_DATA
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* or MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL
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*/
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int mbedtls_ecp_point_write_binary( const mbedtls_ecp_group *grp, const mbedtls_ecp_point *P,
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int format, size_t *olen,
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unsigned char *buf, size_t buflen );
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/**
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* \brief Import a point from unsigned binary data
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*
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* \param grp Group to which the point should belong
|
||
|
* \param P Point to import
|
||
|
* \param buf Input buffer
|
||
|
* \param ilen Actual length of input
|
||
|
*
|
||
|
* \return 0 if successful,
|
||
|
* MBEDTLS_ERR_ECP_BAD_INPUT_DATA if input is invalid,
|
||
|
* MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed,
|
||
|
* MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE if the point format
|
||
|
* is not implemented.
|
||
|
*
|
||
|
* \note This function does NOT check that the point actually
|
||
|
* belongs to the given group, see mbedtls_ecp_check_pubkey() for
|
||
|
* that.
|
||
|
*/
|
||
|
int mbedtls_ecp_point_read_binary( const mbedtls_ecp_group *grp, mbedtls_ecp_point *P,
|
||
|
const unsigned char *buf, size_t ilen );
|
||
|
|
||
|
/**
|
||
|
* \brief Import a point from a TLS ECPoint record
|
||
|
*
|
||
|
* \param grp ECP group used
|
||
|
* \param pt Destination point
|
||
|
* \param buf $(Start of input buffer)
|
||
|
* \param len Buffer length
|
||
|
*
|
||
|
* \note buf is updated to point right after the ECPoint on exit
|
||
|
*
|
||
|
* \return 0 if successful,
|
||
|
* MBEDTLS_ERR_MPI_XXX if initialization failed
|
||
|
* 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 Export a point as a TLS ECPoint record
|
||
|
*
|
||
|
* \param grp ECP group used
|
||
|
* \param pt Point to export
|
||
|
* \param format Export format
|
||
|
* \param olen length of data written
|
||
|
* \param buf Buffer to write to
|
||
|
* \param blen Buffer length
|
||
|
*
|
||
|
* \return 0 if successful,
|
||
|
* or MBEDTLS_ERR_ECP_BAD_INPUT_DATA
|
||
|
* or MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL
|
||
|
*/
|
||
|
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 Set a group using well-known domain parameters
|
||
|
*
|
||
|
* \param grp Destination group
|
||
|
* \param index Index in the list of well-known domain parameters
|
||
|
*
|
||
|
* \return 0 if successful,
|
||
|
* MBEDTLS_ERR_MPI_XXX if initialization failed
|
||
|
* MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE for unkownn groups
|
||
|
*
|
||
|
* \note Index should be a value of RFC 4492's enum NamedCurve,
|
||
|
* usually in the form of a MBEDTLS_ECP_DP_XXX macro.
|
||
|
*/
|
||
|
int mbedtls_ecp_group_load( mbedtls_ecp_group *grp, mbedtls_ecp_group_id index );
|
||
|
|
||
|
/**
|
||
|
* \brief Set a group from a TLS ECParameters record
|
||
|
*
|
||
|
* \param grp Destination group
|
||
|
* \param buf &(Start of input buffer)
|
||
|
* \param len Buffer length
|
||
|
*
|
||
|
* \note buf is updated to point right after ECParameters on exit
|
||
|
*
|
||
|
* \return 0 if successful,
|
||
|
* MBEDTLS_ERR_MPI_XXX if initialization failed
|
||
|
* 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 Write the TLS ECParameters record for a group
|
||
|
*
|
||
|
* \param grp ECP group used
|
||
|
* \param olen Number of bytes actually written
|
||
|
* \param buf Buffer to write to
|
||
|
* \param blen Buffer length
|
||
|
*
|
||
|
* \return 0 if successful,
|
||
|
* or MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL
|
||
|
*/
|
||
|
int mbedtls_ecp_tls_write_group( const mbedtls_ecp_group *grp, size_t *olen,
|
||
|
unsigned char *buf, size_t blen );
|
||
|
|
||
|
/**
|
||
|
* \brief Multiplication by an integer: R = m * P
|
||
|
* (Not thread-safe to use same group in multiple threads)
|
||
|
*
|
||
|
* \note In order to prevent timing attacks, this function
|
||
|
* executes the exact same sequence of (base field)
|
||
|
* operations for any valid m. It avoids any if-branch or
|
||
|
* array index depending on the value of m.
|
||
|
*
|
||
|
* \note If f_rng is not NULL, it is used to randomize intermediate
|
||
|
* results in order to prevent potential timing attacks
|
||
|
* targeting these results. It is recommended to always
|
||
|
* provide a non-NULL f_rng (the overhead is negligible).
|
||
|
*
|
||
|
* \param grp ECP group
|
||
|
* \param R Destination point
|
||
|
* \param m Integer by which to multiply
|
||
|
* \param P Point to multiply
|
||
|
* \param f_rng RNG function (see notes)
|
||
|
* \param p_rng RNG parameter
|
||
|
*
|
||
|
* \return 0 if successful,
|
||
|
* MBEDTLS_ERR_ECP_INVALID_KEY if m is not a valid privkey
|
||
|
* or P is not a valid pubkey,
|
||
|
* MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed
|
||
|
*/
|
||
|
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 Multiplication and addition of two points by integers:
|
||
|
* R = m * P + n * Q
|
||
|
* (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 ECP group
|
||
|
* \param R Destination point
|
||
|
* \param m Integer by which to multiply P
|
||
|
* \param P Point to multiply by m
|
||
|
* \param n Integer by which to multiply Q
|
||
|
* \param Q Point to be multiplied by n
|
||
|
*
|
||
|
* \return 0 if successful,
|
||
|
* MBEDTLS_ERR_ECP_INVALID_KEY if m or n is not a valid privkey
|
||
|
* or P or Q is not a valid pubkey,
|
||
|
* MBEDTLS_ERR_MPI_ALLOC_FAILED if memory allocation failed
|
||
|
*/
|
||
|
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 Check that a point is a valid public key on this curve
|
||
|
*
|
||
|
* \param grp Curve/group the point should belong to
|
||
|
* \param pt Point to check
|
||
|
*
|
||
|
* \return 0 if point is a valid public key,
|
||
|
* MBEDTLS_ERR_ECP_INVALID_KEY otherwise.
|
||
|
*
|
||
|
* \note This function only checks the point is non-zero, has valid
|
||
|
* coordinates and lies on the curve, but not that it is
|
||
|
* indeed a multiple of G. This is additional check is more
|
||
|
* expensive, isn't required by standards, and shouldn't 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 Uses bare components rather than an mbedtls_ecp_keypair structure
|
||
|
* in order to ease use with other structures such as
|
||
|
* mbedtls_ecdh_context of mbedtls_ecdsa_context.
|
||
|
*/
|
||
|
int mbedtls_ecp_check_pubkey( const mbedtls_ecp_group *grp, const mbedtls_ecp_point *pt );
|
||
|
|
||
|
/**
|
||
|
* \brief Check that an mbedtls_mpi is a valid private key for this curve
|
||
|
*
|
||
|
* \param grp Group used
|
||
|
* \param d Integer to check
|
||
|
*
|
||
|
* \return 0 if point is a valid private key,
|
||
|
* MBEDTLS_ERR_ECP_INVALID_KEY otherwise.
|
||
|
*
|
||
|
* \note Uses bare components rather than an mbedtls_ecp_keypair structure
|
||
|
* in order to ease use with other structures such as
|
||
|
* mbedtls_ecdh_context of mbedtls_ecdsa_context.
|
||
|
*/
|
||
|
int mbedtls_ecp_check_privkey( const mbedtls_ecp_group *grp, const mbedtls_mpi *d );
|
||
|
|
||
|
/**
|
||
|
* \brief Generate a keypair with configurable base point
|
||
|
*
|
||
|
* \param grp ECP group
|
||
|
* \param G Chosen base point
|
||
|
* \param d Destination MPI (secret part)
|
||
|
* \param Q Destination point (public part)
|
||
|
* \param f_rng RNG function
|
||
|
* \param p_rng RNG parameter
|
||
|
*
|
||
|
* \return 0 if successful,
|
||
|
* or a MBEDTLS_ERR_ECP_XXX or MBEDTLS_MPI_XXX error code
|
||
|
*
|
||
|
* \note Uses bare components rather than an mbedtls_ecp_keypair structure
|
||
|
* in order to ease use with other structures such as
|
||
|
* mbedtls_ecdh_context of mbedtls_ecdsa_context.
|
||
|
*/
|
||
|
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 Generate a keypair
|
||
|
*
|
||
|
* \param grp ECP group
|
||
|
* \param d Destination MPI (secret part)
|
||
|
* \param Q Destination point (public part)
|
||
|
* \param f_rng RNG function
|
||
|
* \param p_rng RNG parameter
|
||
|
*
|
||
|
* \return 0 if successful,
|
||
|
* or a MBEDTLS_ERR_ECP_XXX or MBEDTLS_MPI_XXX error code
|
||
|
*
|
||
|
* \note Uses bare components rather than an mbedtls_ecp_keypair structure
|
||
|
* in order to ease use with other structures such as
|
||
|
* mbedtls_ecdh_context of mbedtls_ecdsa_context.
|
||
|
*/
|
||
|
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 Generate a keypair
|
||
|
*
|
||
|
* \param grp_id ECP group identifier
|
||
|
* \param key Destination keypair
|
||
|
* \param f_rng RNG function
|
||
|
* \param p_rng RNG parameter
|
||
|
*
|
||
|
* \return 0 if successful,
|
||
|
* or a MBEDTLS_ERR_ECP_XXX or MBEDTLS_MPI_XXX error code
|
||
|
*/
|
||
|
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 Check a public-private key pair
|
||
|
*
|
||
|
* \param pub Keypair structure holding a public key
|
||
|
* \param prv Keypair structure holding a private (plus public) key
|
||
|
*
|
||
|
* \return 0 if successful (keys are valid and match), or
|
||
|
* MBEDTLS_ERR_ECP_BAD_INPUT_DATA, or
|
||
|
* a MBEDTLS_ERR_ECP_XXX or MBEDTLS_ERR_MPI_XXX code.
|
||
|
*/
|
||
|
int mbedtls_ecp_check_pub_priv( const mbedtls_ecp_keypair *pub, const mbedtls_ecp_keypair *prv );
|
||
|
|
||
|
#if defined(MBEDTLS_SELF_TEST)
|
||
|
/**
|
||
|
* \brief Checkup routine
|
||
|
*
|
||
|
* \return 0 if successful, or 1 if a test failed
|
||
|
*/
|
||
|
int mbedtls_ecp_self_test( int verbose );
|
||
|
#endif
|
||
|
|
||
|
#ifdef __cplusplus
|
||
|
}
|
||
|
#endif
|
||
|
|
||
|
#endif /* ecp.h */
|