[398] | 1 | /**
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| 2 | * \file ecp.h
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| 3 | *
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| 4 | * \brief This file provides an API for Elliptic Curves over GF(P) (ECP).
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| 5 | *
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| 6 | * The use of ECP in cryptography and TLS is defined in
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| 7 | * <em>Standards for Efficient Cryptography Group (SECG): SEC1
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| 8 | * Elliptic Curve Cryptography</em> and
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| 9 | * <em>RFC-4492: Elliptic Curve Cryptography (ECC) Cipher Suites
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| 10 | * for Transport Layer Security (TLS)</em>.
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| 11 | *
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| 12 | * <em>RFC-2409: The Internet Key Exchange (IKE)</em> defines ECP
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| 13 | * group types.
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| 14 | *
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| 15 | */
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| 16 |
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| 17 | /*
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| 18 | * Copyright (C) 2006-2018, Arm Limited (or its affiliates), All Rights Reserved
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| 19 | * SPDX-License-Identifier: Apache-2.0
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| 20 | *
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| 21 | * Licensed under the Apache License, Version 2.0 (the "License"); you may
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| 22 | * not use this file except in compliance with the License.
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| 23 | * You may obtain a copy of the License at
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| 24 | *
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| 25 | * http://www.apache.org/licenses/LICENSE-2.0
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| 26 | *
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| 27 | * Unless required by applicable law or agreed to in writing, software
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| 28 | * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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| 29 | * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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| 30 | * See the License for the specific language governing permissions and
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| 31 | * limitations under the License.
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| 32 | *
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| 33 | * This file is part of Mbed TLS (https://tls.mbed.org)
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| 34 | */
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| 35 |
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| 36 | #ifndef MBEDTLS_ECP_H
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| 37 | #define MBEDTLS_ECP_H
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| 38 |
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| 39 | #if !defined(MBEDTLS_CONFIG_FILE)
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| 40 | #include "config.h"
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| 41 | #else
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| 42 | #include MBEDTLS_CONFIG_FILE
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| 43 | #endif
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| 44 |
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| 45 | #include "bignum.h"
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| 46 |
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| 47 | /*
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| 48 | * ECP error codes
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| 49 | */
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| 50 | #define MBEDTLS_ERR_ECP_BAD_INPUT_DATA -0x4F80 /**< Bad input parameters to function. */
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| 51 | #define MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL -0x4F00 /**< The buffer is too small to write to. */
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| 52 | #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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| 53 | #define MBEDTLS_ERR_ECP_VERIFY_FAILED -0x4E00 /**< The signature is not valid. */
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| 54 | #define MBEDTLS_ERR_ECP_ALLOC_FAILED -0x4D80 /**< Memory allocation failed. */
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| 55 | #define MBEDTLS_ERR_ECP_RANDOM_FAILED -0x4D00 /**< Generation of random value, such as ephemeral key, failed. */
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| 56 | #define MBEDTLS_ERR_ECP_INVALID_KEY -0x4C80 /**< Invalid private or public key. */
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| 57 | #define MBEDTLS_ERR_ECP_SIG_LEN_MISMATCH -0x4C00 /**< The buffer contains a valid signature followed by more data. */
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| 58 |
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| 59 | /* MBEDTLS_ERR_ECP_HW_ACCEL_FAILED is deprecated and should not be used. */
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| 60 | #define MBEDTLS_ERR_ECP_HW_ACCEL_FAILED -0x4B80 /**< The ECP hardware accelerator failed. */
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| 61 |
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| 62 | #define MBEDTLS_ERR_ECP_IN_PROGRESS -0x4B00 /**< Operation in progress, call again with the same parameters to continue. */
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| 63 |
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| 64 | #ifdef __cplusplus
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| 65 | extern "C" {
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| 66 | #endif
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| 67 |
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| 68 | /**
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| 69 | * Domain-parameter identifiers: curve, subgroup, and generator.
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| 70 | *
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| 71 | * \note Only curves over prime fields are supported.
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| 72 | *
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| 73 | * \warning This library does not support validation of arbitrary domain
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| 74 | * parameters. Therefore, only standardized domain parameters from trusted
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| 75 | * sources should be used. See mbedtls_ecp_group_load().
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| 76 | */
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| 77 | typedef enum
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| 78 | {
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| 79 | MBEDTLS_ECP_DP_NONE = 0, /*!< Curve not defined. */
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| 80 | MBEDTLS_ECP_DP_SECP192R1, /*!< Domain parameters for the 192-bit curve defined by FIPS 186-4 and SEC1. */
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| 81 | MBEDTLS_ECP_DP_SECP224R1, /*!< Domain parameters for the 224-bit curve defined by FIPS 186-4 and SEC1. */
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| 82 | MBEDTLS_ECP_DP_SECP256R1, /*!< Domain parameters for the 256-bit curve defined by FIPS 186-4 and SEC1. */
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| 83 | MBEDTLS_ECP_DP_SECP384R1, /*!< Domain parameters for the 384-bit curve defined by FIPS 186-4 and SEC1. */
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| 84 | MBEDTLS_ECP_DP_SECP521R1, /*!< Domain parameters for the 521-bit curve defined by FIPS 186-4 and SEC1. */
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| 85 | MBEDTLS_ECP_DP_BP256R1, /*!< Domain parameters for 256-bit Brainpool curve. */
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| 86 | MBEDTLS_ECP_DP_BP384R1, /*!< Domain parameters for 384-bit Brainpool curve. */
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| 87 | MBEDTLS_ECP_DP_BP512R1, /*!< Domain parameters for 512-bit Brainpool curve. */
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| 88 | MBEDTLS_ECP_DP_CURVE25519, /*!< Domain parameters for Curve25519. */
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| 89 | MBEDTLS_ECP_DP_SECP192K1, /*!< Domain parameters for 192-bit "Koblitz" curve. */
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| 90 | MBEDTLS_ECP_DP_SECP224K1, /*!< Domain parameters for 224-bit "Koblitz" curve. */
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| 91 | MBEDTLS_ECP_DP_SECP256K1, /*!< Domain parameters for 256-bit "Koblitz" curve. */
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| 92 | MBEDTLS_ECP_DP_CURVE448, /*!< Domain parameters for Curve448. */
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| 93 | } mbedtls_ecp_group_id;
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| 94 |
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| 95 | /**
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| 96 | * The number of supported curves, plus one for #MBEDTLS_ECP_DP_NONE.
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| 97 | *
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| 98 | * \note Montgomery curves are currently excluded.
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| 99 | */
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| 100 | #define MBEDTLS_ECP_DP_MAX 12
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| 101 |
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| 102 | /**
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| 103 | * Curve information, for use by other modules.
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| 104 | */
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| 105 | typedef struct mbedtls_ecp_curve_info
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| 106 | {
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| 107 | mbedtls_ecp_group_id grp_id; /*!< An internal identifier. */
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| 108 | uint16_t tls_id; /*!< The TLS NamedCurve identifier. */
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| 109 | uint16_t bit_size; /*!< The curve size in bits. */
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| 110 | const char *name; /*!< A human-friendly name. */
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| 111 | } mbedtls_ecp_curve_info;
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| 112 |
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| 113 | /**
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| 114 | * \brief The ECP point structure, in Jacobian coordinates.
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| 115 | *
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| 116 | * \note All functions expect and return points satisfying
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| 117 | * the following condition: <code>Z == 0</code> or
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| 118 | * <code>Z == 1</code>. Other values of \p Z are
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| 119 | * used only by internal functions.
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| 120 | * The point is zero, or "at infinity", if <code>Z == 0</code>.
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| 121 | * Otherwise, \p X and \p Y are its standard (affine)
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| 122 | * coordinates.
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| 123 | */
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| 124 | typedef struct mbedtls_ecp_point
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| 125 | {
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| 126 | mbedtls_mpi X; /*!< The X coordinate of the ECP point. */
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| 127 | mbedtls_mpi Y; /*!< The Y coordinate of the ECP point. */
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| 128 | mbedtls_mpi Z; /*!< The Z coordinate of the ECP point. */
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| 129 | }
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| 130 | mbedtls_ecp_point;
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| 131 |
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| 132 | #if !defined(MBEDTLS_ECP_ALT)
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| 133 | /*
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| 134 | * default mbed TLS elliptic curve arithmetic implementation
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| 135 | *
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| 136 | * (in case MBEDTLS_ECP_ALT is defined then the developer has to provide an
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| 137 | * alternative implementation for the whole module and it will replace this
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| 138 | * one.)
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| 139 | */
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| 140 |
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| 141 | /**
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| 142 | * \brief The ECP group structure.
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| 143 | *
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| 144 | * We consider two types of curve equations:
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| 145 | * <ul><li>Short Weierstrass: <code>y^2 = x^3 + A x + B mod P</code>
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| 146 | * (SEC1 + RFC-4492)</li>
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| 147 | * <li>Montgomery: <code>y^2 = x^3 + A x^2 + x mod P</code> (Curve25519,
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| 148 | * Curve448)</li></ul>
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| 149 | * In both cases, the generator (\p G) for a prime-order subgroup is fixed.
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| 150 | *
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| 151 | * For Short Weierstrass, this subgroup is the whole curve, and its
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| 152 | * cardinality is denoted by \p N. Our code requires that \p N is an
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| 153 | * odd prime as mbedtls_ecp_mul() requires an odd number, and
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| 154 | * mbedtls_ecdsa_sign() requires that it is prime for blinding purposes.
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| 155 | *
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| 156 | * For Montgomery curves, we do not store \p A, but <code>(A + 2) / 4</code>,
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| 157 | * which is the quantity used in the formulas. Additionally, \p nbits is
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| 158 | * not the size of \p N but the required size for private keys.
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| 159 | *
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| 160 | * If \p modp is NULL, reduction modulo \p P is done using a generic algorithm.
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| 161 | * Otherwise, \p modp must point to a function that takes an \p mbedtls_mpi in the
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| 162 | * range of <code>0..2^(2*pbits)-1</code>, and transforms it in-place to an integer
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| 163 | * which is congruent mod \p P to the given MPI, and is close enough to \p pbits
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| 164 | * in size, so that it may be efficiently brought in the 0..P-1 range by a few
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| 165 | * additions or subtractions. Therefore, it is only an approximative modular
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| 166 | * reduction. It must return 0 on success and non-zero on failure.
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| 167 | *
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| 168 | * \note Alternative implementations must keep the group IDs distinct. If
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| 169 | * two group structures have the same ID, then they must be
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| 170 | * identical.
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| 171 | *
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| 172 | */
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| 173 | typedef struct mbedtls_ecp_group
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| 174 | {
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| 175 | mbedtls_ecp_group_id id; /*!< An internal group identifier. */
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| 176 | mbedtls_mpi P; /*!< The prime modulus of the base field. */
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| 177 | mbedtls_mpi A; /*!< For Short Weierstrass: \p A in the equation. For
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| 178 | Montgomery curves: <code>(A + 2) / 4</code>. */
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| 179 | mbedtls_mpi B; /*!< For Short Weierstrass: \p B in the equation.
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| 180 | For Montgomery curves: unused. */
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| 181 | mbedtls_ecp_point G; /*!< The generator of the subgroup used. */
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| 182 | mbedtls_mpi N; /*!< The order of \p G. */
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| 183 | size_t pbits; /*!< The number of bits in \p P.*/
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| 184 | size_t nbits; /*!< For Short Weierstrass: The number of bits in \p P.
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| 185 | For Montgomery curves: the number of bits in the
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| 186 | private keys. */
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| 187 | unsigned int h; /*!< \internal 1 if the constants are static. */
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| 188 | int (*modp)(mbedtls_mpi *); /*!< The function for fast pseudo-reduction
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| 189 | mod \p P (see above).*/
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| 190 | int (*t_pre)(mbedtls_ecp_point *, void *); /*!< Unused. */
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| 191 | int (*t_post)(mbedtls_ecp_point *, void *); /*!< Unused. */
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| 192 | void *t_data; /*!< Unused. */
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| 193 | mbedtls_ecp_point *T; /*!< Pre-computed points for ecp_mul_comb(). */
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| 194 | size_t T_size; /*!< The number of pre-computed points. */
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| 195 | }
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| 196 | mbedtls_ecp_group;
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| 197 |
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| 198 | /**
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| 199 | * \name SECTION: Module settings
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| 200 | *
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| 201 | * The configuration options you can set for this module are in this section.
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| 202 | * Either change them in config.h, or define them using the compiler command line.
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| 203 | * \{
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| 204 | */
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| 205 |
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| 206 | #if !defined(MBEDTLS_ECP_MAX_BITS)
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| 207 | /**
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| 208 | * The maximum size of the groups, that is, of \c N and \c P.
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| 209 | */
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| 210 | #define MBEDTLS_ECP_MAX_BITS 521 /**< The maximum size of groups, in bits. */
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| 211 | #endif
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| 212 |
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| 213 | #define MBEDTLS_ECP_MAX_BYTES ( ( MBEDTLS_ECP_MAX_BITS + 7 ) / 8 )
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| 214 | #define MBEDTLS_ECP_MAX_PT_LEN ( 2 * MBEDTLS_ECP_MAX_BYTES + 1 )
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| 215 |
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| 216 | #if !defined(MBEDTLS_ECP_WINDOW_SIZE)
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| 217 | /*
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| 218 | * Maximum "window" size used for point multiplication.
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| 219 | * Default: 6.
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| 220 | * Minimum value: 2. Maximum value: 7.
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| 221 | *
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| 222 | * Result is an array of at most ( 1 << ( MBEDTLS_ECP_WINDOW_SIZE - 1 ) )
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| 223 | * points used for point multiplication. This value is directly tied to EC
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| 224 | * peak memory usage, so decreasing it by one should roughly cut memory usage
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| 225 | * by two (if large curves are in use).
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| 226 | *
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| 227 | * Reduction in size may reduce speed, but larger curves are impacted first.
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| 228 | * Sample performances (in ECDHE handshakes/s, with FIXED_POINT_OPTIM = 1):
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| 229 | * w-size: 6 5 4 3 2
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| 230 | * 521 145 141 135 120 97
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| 231 | * 384 214 209 198 177 146
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| 232 | * 256 320 320 303 262 226
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| 233 | * 224 475 475 453 398 342
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| 234 | * 192 640 640 633 587 476
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| 235 | */
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| 236 | #define MBEDTLS_ECP_WINDOW_SIZE 6 /**< The maximum window size used. */
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| 237 | #endif /* MBEDTLS_ECP_WINDOW_SIZE */
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| 238 |
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| 239 | #if !defined(MBEDTLS_ECP_FIXED_POINT_OPTIM)
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| 240 | /*
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| 241 | * Trade memory for speed on fixed-point multiplication.
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| 242 | *
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| 243 | * This speeds up repeated multiplication of the generator (that is, the
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| 244 | * multiplication in ECDSA signatures, and half of the multiplications in
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| 245 | * ECDSA verification and ECDHE) by a factor roughly 3 to 4.
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| 246 | *
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| 247 | * The cost is increasing EC peak memory usage by a factor roughly 2.
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| 248 | *
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| 249 | * Change this value to 0 to reduce peak memory usage.
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| 250 | */
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| 251 | #define MBEDTLS_ECP_FIXED_POINT_OPTIM 1 /**< Enable fixed-point speed-up. */
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| 252 | #endif /* MBEDTLS_ECP_FIXED_POINT_OPTIM */
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| 253 |
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| 254 | /* \} name SECTION: Module settings */
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| 255 |
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| 256 | #else /* MBEDTLS_ECP_ALT */
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| 257 | #include "ecp_alt.h"
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| 258 | #endif /* MBEDTLS_ECP_ALT */
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| 259 |
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| 260 | #if defined(MBEDTLS_ECP_RESTARTABLE)
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| 261 |
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| 262 | /**
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| 263 | * \brief Internal restart context for multiplication
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| 264 | *
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| 265 | * \note Opaque struct
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| 266 | */
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| 267 | typedef struct mbedtls_ecp_restart_mul mbedtls_ecp_restart_mul_ctx;
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| 268 |
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| 269 | /**
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| 270 | * \brief Internal restart context for ecp_muladd()
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| 271 | *
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| 272 | * \note Opaque struct
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| 273 | */
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| 274 | typedef struct mbedtls_ecp_restart_muladd mbedtls_ecp_restart_muladd_ctx;
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| 275 |
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| 276 | /**
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| 277 | * \brief General context for resuming ECC operations
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| 278 | */
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| 279 | typedef struct
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| 280 | {
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| 281 | unsigned ops_done; /*!< current ops count */
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| 282 | unsigned depth; /*!< call depth (0 = top-level) */
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| 283 | mbedtls_ecp_restart_mul_ctx *rsm; /*!< ecp_mul_comb() sub-context */
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| 284 | mbedtls_ecp_restart_muladd_ctx *ma; /*!< ecp_muladd() sub-context */
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| 285 | } mbedtls_ecp_restart_ctx;
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| 286 |
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| 287 | /*
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| 288 | * Operation counts for restartable functions
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| 289 | */
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| 290 | #define MBEDTLS_ECP_OPS_CHK 3 /*!< basic ops count for ecp_check_pubkey() */
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| 291 | #define MBEDTLS_ECP_OPS_DBL 8 /*!< basic ops count for ecp_double_jac() */
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| 292 | #define MBEDTLS_ECP_OPS_ADD 11 /*!< basic ops count for see ecp_add_mixed() */
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| 293 | #define MBEDTLS_ECP_OPS_INV 120 /*!< empirical equivalent for mpi_mod_inv() */
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| 294 |
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| 295 | /**
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| 296 | * \brief Internal; for restartable functions in other modules.
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| 297 | * Check and update basic ops budget.
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| 298 | *
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| 299 | * \param grp Group structure
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| 300 | * \param rs_ctx Restart context
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| 301 | * \param ops Number of basic ops to do
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| 302 | *
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| 303 | * \return \c 0 if doing \p ops basic ops is still allowed,
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| 304 | * \return #MBEDTLS_ERR_ECP_IN_PROGRESS otherwise.
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| 305 | */
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| 306 | int mbedtls_ecp_check_budget( const mbedtls_ecp_group *grp,
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| 307 | mbedtls_ecp_restart_ctx *rs_ctx,
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| 308 | unsigned ops );
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| 309 |
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| 310 | /* Utility macro for checking and updating ops budget */
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| 311 | #define MBEDTLS_ECP_BUDGET( ops ) \
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| 312 | MBEDTLS_MPI_CHK( mbedtls_ecp_check_budget( grp, rs_ctx, \
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| 313 | (unsigned) (ops) ) );
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| 314 |
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| 315 | #else /* MBEDTLS_ECP_RESTARTABLE */
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| 316 |
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| 317 | #define MBEDTLS_ECP_BUDGET( ops ) /* no-op; for compatibility */
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| 318 |
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| 319 | /* We want to declare restartable versions of existing functions anyway */
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| 320 | typedef void mbedtls_ecp_restart_ctx;
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| 321 |
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| 322 | #endif /* MBEDTLS_ECP_RESTARTABLE */
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| 323 |
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| 324 | /**
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| 325 | * \brief The ECP key-pair structure.
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| 326 | *
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| 327 | * A generic key-pair that may be used for ECDSA and fixed ECDH, for example.
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| 328 | *
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| 329 | * \note Members are deliberately in the same order as in the
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| 330 | * ::mbedtls_ecdsa_context structure.
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| 331 | */
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| 332 | typedef struct mbedtls_ecp_keypair
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| 333 | {
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| 334 | mbedtls_ecp_group grp; /*!< Elliptic curve and base point */
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| 335 | mbedtls_mpi d; /*!< our secret value */
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| 336 | mbedtls_ecp_point Q; /*!< our public value */
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| 337 | }
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| 338 | mbedtls_ecp_keypair;
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| 339 |
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| 340 | /*
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| 341 | * Point formats, from RFC 4492's enum ECPointFormat
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| 342 | */
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| 343 | #define MBEDTLS_ECP_PF_UNCOMPRESSED 0 /**< Uncompressed point format. */
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| 344 | #define MBEDTLS_ECP_PF_COMPRESSED 1 /**< Compressed point format. */
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| 345 |
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| 346 | /*
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| 347 | * Some other constants from RFC 4492
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| 348 | */
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| 349 | #define MBEDTLS_ECP_TLS_NAMED_CURVE 3 /**< The named_curve of ECCurveType. */
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| 350 |
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| 351 | #if defined(MBEDTLS_ECP_RESTARTABLE)
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| 352 | /**
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| 353 | * \brief Set the maximum number of basic operations done in a row.
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| 354 | *
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| 355 | * If more operations are needed to complete a computation,
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| 356 | * #MBEDTLS_ERR_ECP_IN_PROGRESS will be returned by the
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| 357 | * function performing the computation. It is then the
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| 358 | * caller's responsibility to either call again with the same
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| 359 | * parameters until it returns 0 or an error code; or to free
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| 360 | * the restart context if the operation is to be aborted.
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| 361 | *
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| 362 | * It is strictly required that all input parameters and the
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| 363 | * restart context be the same on successive calls for the
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| 364 | * same operation, but output parameters need not be the
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| 365 | * same; they must not be used until the function finally
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| 366 | * returns 0.
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| 367 | *
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| 368 | * This only applies to functions whose documentation
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| 369 | * mentions they may return #MBEDTLS_ERR_ECP_IN_PROGRESS (or
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| 370 | * #MBEDTLS_ERR_SSL_CRYPTO_IN_PROGRESS for functions in the
|
---|
| 371 | * SSL module). For functions that accept a "restart context"
|
---|
| 372 | * argument, passing NULL disables restart and makes the
|
---|
| 373 | * function equivalent to the function with the same name
|
---|
| 374 | * with \c _restartable removed. For functions in the ECDH
|
---|
| 375 | * module, restart is disabled unless the function accepts
|
---|
| 376 | * an "ECDH context" argument and
|
---|
| 377 | * mbedtls_ecdh_enable_restart() was previously called on
|
---|
| 378 | * that context. For function in the SSL module, restart is
|
---|
| 379 | * only enabled for specific sides and key exchanges
|
---|
| 380 | * (currently only for clients and ECDHE-ECDSA).
|
---|
| 381 | *
|
---|
| 382 | * \param max_ops Maximum number of basic operations done in a row.
|
---|
| 383 | * Default: 0 (unlimited).
|
---|
| 384 | * Lower (non-zero) values mean ECC functions will block for
|
---|
| 385 | * a lesser maximum amount of time.
|
---|
| 386 | *
|
---|
| 387 | * \note A "basic operation" is defined as a rough equivalent of a
|
---|
| 388 | * multiplication in GF(p) for the NIST P-256 curve.
|
---|
| 389 | * As an indication, with default settings, a scalar
|
---|
| 390 | * multiplication (full run of \c mbedtls_ecp_mul()) is:
|
---|
| 391 | * - about 3300 basic operations for P-256
|
---|
| 392 | * - about 9400 basic operations for P-384
|
---|
| 393 | *
|
---|
| 394 | * \note Very low values are not always respected: sometimes
|
---|
| 395 | * functions need to block for a minimum number of
|
---|
| 396 | * operations, and will do so even if max_ops is set to a
|
---|
| 397 | * lower value. That minimum depends on the curve size, and
|
---|
| 398 | * can be made lower by decreasing the value of
|
---|
| 399 | * \c MBEDTLS_ECP_WINDOW_SIZE. As an indication, here is the
|
---|
| 400 | * lowest effective value for various curves and values of
|
---|
| 401 | * that parameter (w for short):
|
---|
| 402 | * w=6 w=5 w=4 w=3 w=2
|
---|
| 403 | * P-256 208 208 160 136 124
|
---|
| 404 | * P-384 682 416 320 272 248
|
---|
| 405 | * P-521 1364 832 640 544 496
|
---|
| 406 | *
|
---|
| 407 | * \note This setting is currently ignored by Curve25519.
|
---|
| 408 | */
|
---|
| 409 | void mbedtls_ecp_set_max_ops( unsigned max_ops );
|
---|
| 410 |
|
---|
| 411 | /**
|
---|
| 412 | * \brief Check if restart is enabled (max_ops != 0)
|
---|
| 413 | *
|
---|
| 414 | * \return \c 0 if \c max_ops == 0 (restart disabled)
|
---|
| 415 | * \return \c 1 otherwise (restart enabled)
|
---|
| 416 | */
|
---|
| 417 | int mbedtls_ecp_restart_is_enabled( void );
|
---|
| 418 | #endif /* MBEDTLS_ECP_RESTARTABLE */
|
---|
| 419 |
|
---|
| 420 | /**
|
---|
| 421 | * \brief This function retrieves the information defined in
|
---|
| 422 | * mbedtls_ecp_curve_info() for all supported curves in order
|
---|
| 423 | * of preference.
|
---|
| 424 | *
|
---|
| 425 | * \return A statically allocated array. The last entry is 0.
|
---|
| 426 | */
|
---|
| 427 | const mbedtls_ecp_curve_info *mbedtls_ecp_curve_list( void );
|
---|
| 428 |
|
---|
| 429 | /**
|
---|
| 430 | * \brief This function retrieves the list of internal group
|
---|
| 431 | * identifiers of all supported curves in the order of
|
---|
| 432 | * preference.
|
---|
| 433 | *
|
---|
| 434 | * \return A statically allocated array,
|
---|
| 435 | * terminated with MBEDTLS_ECP_DP_NONE.
|
---|
| 436 | */
|
---|
| 437 | const mbedtls_ecp_group_id *mbedtls_ecp_grp_id_list( void );
|
---|
| 438 |
|
---|
| 439 | /**
|
---|
| 440 | * \brief This function retrieves curve information from an internal
|
---|
| 441 | * group identifier.
|
---|
| 442 | *
|
---|
| 443 | * \param grp_id An \c MBEDTLS_ECP_DP_XXX value.
|
---|
| 444 | *
|
---|
| 445 | * \return The associated curve information on success.
|
---|
| 446 | * \return NULL on failure.
|
---|
| 447 | */
|
---|
| 448 | const mbedtls_ecp_curve_info *mbedtls_ecp_curve_info_from_grp_id( mbedtls_ecp_group_id grp_id );
|
---|
| 449 |
|
---|
| 450 | /**
|
---|
| 451 | * \brief This function retrieves curve information from a TLS
|
---|
| 452 | * NamedCurve value.
|
---|
| 453 | *
|
---|
| 454 | * \param tls_id An \c MBEDTLS_ECP_DP_XXX value.
|
---|
| 455 | *
|
---|
| 456 | * \return The associated curve information on success.
|
---|
| 457 | * \return NULL on failure.
|
---|
| 458 | */
|
---|
| 459 | const mbedtls_ecp_curve_info *mbedtls_ecp_curve_info_from_tls_id( uint16_t tls_id );
|
---|
| 460 |
|
---|
| 461 | /**
|
---|
| 462 | * \brief This function retrieves curve information from a
|
---|
| 463 | * human-readable name.
|
---|
| 464 | *
|
---|
| 465 | * \param name The human-readable name.
|
---|
| 466 | *
|
---|
| 467 | * \return The associated curve information on success.
|
---|
| 468 | * \return NULL on failure.
|
---|
| 469 | */
|
---|
| 470 | const mbedtls_ecp_curve_info *mbedtls_ecp_curve_info_from_name( const char *name );
|
---|
| 471 |
|
---|
| 472 | /**
|
---|
| 473 | * \brief This function initializes a point as zero.
|
---|
| 474 | *
|
---|
| 475 | * \param pt The point to initialize.
|
---|
| 476 | */
|
---|
| 477 | void mbedtls_ecp_point_init( mbedtls_ecp_point *pt );
|
---|
| 478 |
|
---|
| 479 | /**
|
---|
| 480 | * \brief This function initializes an ECP group context
|
---|
| 481 | * without loading any domain parameters.
|
---|
| 482 | *
|
---|
| 483 | * \note After this function is called, domain parameters
|
---|
| 484 | * for various ECP groups can be loaded through the
|
---|
| 485 | * mbedtls_ecp_load() or mbedtls_ecp_tls_read_group()
|
---|
| 486 | * functions.
|
---|
| 487 | */
|
---|
| 488 | void mbedtls_ecp_group_init( mbedtls_ecp_group *grp );
|
---|
| 489 |
|
---|
| 490 | /**
|
---|
| 491 | * \brief This function initializes a key pair as an invalid one.
|
---|
| 492 | *
|
---|
| 493 | * \param key The key pair to initialize.
|
---|
| 494 | */
|
---|
| 495 | void mbedtls_ecp_keypair_init( mbedtls_ecp_keypair *key );
|
---|
| 496 |
|
---|
| 497 | /**
|
---|
| 498 | * \brief This function frees the components of a point.
|
---|
| 499 | *
|
---|
| 500 | * \param pt The point to free.
|
---|
| 501 | */
|
---|
| 502 | void mbedtls_ecp_point_free( mbedtls_ecp_point *pt );
|
---|
| 503 |
|
---|
| 504 | /**
|
---|
| 505 | * \brief This function frees the components of an ECP group.
|
---|
| 506 | *
|
---|
| 507 | * \param grp The group to free. This may be \c NULL, in which
|
---|
| 508 | * case this function returns immediately. If it is not
|
---|
| 509 | * \c NULL, it must point to an initialized ECP group.
|
---|
| 510 | */
|
---|
| 511 | void mbedtls_ecp_group_free( mbedtls_ecp_group *grp );
|
---|
| 512 |
|
---|
| 513 | /**
|
---|
| 514 | * \brief This function frees the components of a key pair.
|
---|
| 515 | *
|
---|
| 516 | * \param key The key pair to free. This may be \c NULL, in which
|
---|
| 517 | * case this function returns immediately. If it is not
|
---|
| 518 | * \c NULL, it must point to an initialized ECP key pair.
|
---|
| 519 | */
|
---|
| 520 | void mbedtls_ecp_keypair_free( mbedtls_ecp_keypair *key );
|
---|
| 521 |
|
---|
| 522 | #if defined(MBEDTLS_ECP_RESTARTABLE)
|
---|
| 523 | /**
|
---|
| 524 | * \brief Initialize a restart context.
|
---|
| 525 | *
|
---|
| 526 | * \param ctx The restart context to initialize. This must
|
---|
| 527 | * not be \c NULL.
|
---|
| 528 | */
|
---|
| 529 | void mbedtls_ecp_restart_init( mbedtls_ecp_restart_ctx *ctx );
|
---|
| 530 |
|
---|
| 531 | /**
|
---|
| 532 | * \brief Free the components of a restart context.
|
---|
| 533 | *
|
---|
| 534 | * \param ctx The restart context to free. This may be \c NULL, in which
|
---|
| 535 | * case this function returns immediately. If it is not
|
---|
| 536 | * \c NULL, it must point to an initialized restart context.
|
---|
| 537 | */
|
---|
| 538 | void mbedtls_ecp_restart_free( mbedtls_ecp_restart_ctx *ctx );
|
---|
| 539 | #endif /* MBEDTLS_ECP_RESTARTABLE */
|
---|
| 540 |
|
---|
| 541 | /**
|
---|
| 542 | * \brief This function copies the contents of point \p Q into
|
---|
| 543 | * point \p P.
|
---|
| 544 | *
|
---|
| 545 | * \param P The destination point. This must be initialized.
|
---|
| 546 | * \param Q The source point. This must be initialized.
|
---|
| 547 | *
|
---|
| 548 | * \return \c 0 on success.
|
---|
| 549 | * \return #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure.
|
---|
| 550 | * \return Another negative error code for other kinds of failure.
|
---|
| 551 | */
|
---|
| 552 | int mbedtls_ecp_copy( mbedtls_ecp_point *P, const mbedtls_ecp_point *Q );
|
---|
| 553 |
|
---|
| 554 | /**
|
---|
| 555 | * \brief This function copies the contents of group \p src into
|
---|
| 556 | * group \p dst.
|
---|
| 557 | *
|
---|
| 558 | * \param dst The destination group. This must be initialized.
|
---|
| 559 | * \param src The source group. This must be initialized.
|
---|
| 560 | *
|
---|
| 561 | * \return \c 0 on success.
|
---|
| 562 | * \return #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure.
|
---|
| 563 | * \return Another negative error code on other kinds of failure.
|
---|
| 564 | */
|
---|
| 565 | int mbedtls_ecp_group_copy( mbedtls_ecp_group *dst,
|
---|
| 566 | const mbedtls_ecp_group *src );
|
---|
| 567 |
|
---|
| 568 | /**
|
---|
| 569 | * \brief This function sets a point to the point at infinity.
|
---|
| 570 | *
|
---|
| 571 | * \param pt The point to set. This must be initialized.
|
---|
| 572 | *
|
---|
| 573 | * \return \c 0 on success.
|
---|
| 574 | * \return #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure.
|
---|
| 575 | * \return Another negative error code on other kinds of failure.
|
---|
| 576 | */
|
---|
| 577 | int mbedtls_ecp_set_zero( mbedtls_ecp_point *pt );
|
---|
| 578 |
|
---|
| 579 | /**
|
---|
| 580 | * \brief This function checks if a point is the point at infinity.
|
---|
| 581 | *
|
---|
| 582 | * \param pt The point to test. This must be initialized.
|
---|
| 583 | *
|
---|
| 584 | * \return \c 1 if the point is zero.
|
---|
| 585 | * \return \c 0 if the point is non-zero.
|
---|
| 586 | * \return A negative error code on failure.
|
---|
| 587 | */
|
---|
| 588 | int mbedtls_ecp_is_zero( mbedtls_ecp_point *pt );
|
---|
| 589 |
|
---|
| 590 | /**
|
---|
| 591 | * \brief This function compares two points.
|
---|
| 592 | *
|
---|
| 593 | * \note This assumes that the points are normalized. Otherwise,
|
---|
| 594 | * they may compare as "not equal" even if they are.
|
---|
| 595 | *
|
---|
| 596 | * \param P The first point to compare. This must be initialized.
|
---|
| 597 | * \param Q The second point to compare. This must be initialized.
|
---|
| 598 | *
|
---|
| 599 | * \return \c 0 if the points are equal.
|
---|
| 600 | * \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if the points are not equal.
|
---|
| 601 | */
|
---|
| 602 | int mbedtls_ecp_point_cmp( const mbedtls_ecp_point *P,
|
---|
| 603 | const mbedtls_ecp_point *Q );
|
---|
| 604 |
|
---|
| 605 | /**
|
---|
| 606 | * \brief This function imports a non-zero point from two ASCII
|
---|
| 607 | * strings.
|
---|
| 608 | *
|
---|
| 609 | * \param P The destination point. This must be initialized.
|
---|
| 610 | * \param radix The numeric base of the input.
|
---|
| 611 | * \param x The first affine coordinate, as a null-terminated string.
|
---|
| 612 | * \param y The second affine coordinate, as a null-terminated string.
|
---|
| 613 | *
|
---|
| 614 | * \return \c 0 on success.
|
---|
| 615 | * \return An \c MBEDTLS_ERR_MPI_XXX error code on failure.
|
---|
| 616 | */
|
---|
| 617 | int mbedtls_ecp_point_read_string( mbedtls_ecp_point *P, int radix,
|
---|
| 618 | const char *x, const char *y );
|
---|
| 619 |
|
---|
| 620 | /**
|
---|
| 621 | * \brief This function exports a point into unsigned binary data.
|
---|
| 622 | *
|
---|
| 623 | * \param grp The group to which the point should belong.
|
---|
| 624 | * This must be initialized and have group parameters
|
---|
| 625 | * set, for example through mbedtls_ecp_group_load().
|
---|
| 626 | * \param P The point to export. This must be initialized.
|
---|
| 627 | * \param format The point format. This must be either
|
---|
| 628 | * #MBEDTLS_ECP_PF_COMPRESSED or #MBEDTLS_ECP_PF_UNCOMPRESSED.
|
---|
| 629 | * \param olen The address at which to store the length of
|
---|
| 630 | * the output in Bytes. This must not be \c NULL.
|
---|
| 631 | * \param buf The output buffer. This must be a writable buffer
|
---|
| 632 | * of length \p buflen Bytes.
|
---|
| 633 | * \param buflen The length of the output buffer \p buf in Bytes.
|
---|
| 634 | *
|
---|
| 635 | * \return \c 0 on success.
|
---|
| 636 | * \return #MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL if the output buffer
|
---|
| 637 | * is too small to hold the point.
|
---|
| 638 | * \return Another negative error code on other kinds of failure.
|
---|
| 639 | */
|
---|
| 640 | int mbedtls_ecp_point_write_binary( const mbedtls_ecp_group *grp, const mbedtls_ecp_point *P,
|
---|
| 641 | int format, size_t *olen,
|
---|
| 642 | unsigned char *buf, size_t buflen );
|
---|
| 643 |
|
---|
| 644 | /**
|
---|
| 645 | * \brief This function imports a point from unsigned binary data.
|
---|
| 646 | *
|
---|
| 647 | * \note This function does not check that the point actually
|
---|
| 648 | * belongs to the given group, see mbedtls_ecp_check_pubkey()
|
---|
| 649 | * for that.
|
---|
| 650 | *
|
---|
| 651 | * \param grp The group to which the point should belong.
|
---|
| 652 | * This must be initialized and have group parameters
|
---|
| 653 | * set, for example through mbedtls_ecp_group_load().
|
---|
| 654 | * \param P The destination context to import the point to.
|
---|
| 655 | * This must be initialized.
|
---|
| 656 | * \param buf The input buffer. This must be a readable buffer
|
---|
| 657 | * of length \p ilen Bytes.
|
---|
| 658 | * \param ilen The length of the input buffer \p buf in Bytes.
|
---|
| 659 | *
|
---|
| 660 | * \return \c 0 on success.
|
---|
| 661 | * \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if the input is invalid.
|
---|
| 662 | * \return #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure.
|
---|
| 663 | * \return #MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE if the point format
|
---|
| 664 | * is not implemented.
|
---|
| 665 | */
|
---|
| 666 | int mbedtls_ecp_point_read_binary( const mbedtls_ecp_group *grp,
|
---|
| 667 | mbedtls_ecp_point *P,
|
---|
| 668 | const unsigned char *buf, size_t ilen );
|
---|
| 669 |
|
---|
| 670 | /**
|
---|
| 671 | * \brief This function imports a point from a TLS ECPoint record.
|
---|
| 672 | *
|
---|
| 673 | * \note On function return, \p *buf is updated to point immediately
|
---|
| 674 | * after the ECPoint record.
|
---|
| 675 | *
|
---|
| 676 | * \param grp The ECP group to use.
|
---|
| 677 | * This must be initialized and have group parameters
|
---|
| 678 | * set, for example through mbedtls_ecp_group_load().
|
---|
| 679 | * \param pt The destination point.
|
---|
| 680 | * \param buf The address of the pointer to the start of the input buffer.
|
---|
| 681 | * \param len The length of the buffer.
|
---|
| 682 | *
|
---|
| 683 | * \return \c 0 on success.
|
---|
| 684 | * \return An \c MBEDTLS_ERR_MPI_XXX error code on initialization
|
---|
| 685 | * failure.
|
---|
| 686 | * \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if input is invalid.
|
---|
| 687 | */
|
---|
| 688 | int mbedtls_ecp_tls_read_point( const mbedtls_ecp_group *grp,
|
---|
| 689 | mbedtls_ecp_point *pt,
|
---|
| 690 | const unsigned char **buf, size_t len );
|
---|
| 691 |
|
---|
| 692 | /**
|
---|
| 693 | * \brief This function exports a point as a TLS ECPoint record
|
---|
| 694 | * defined in RFC 4492, Section 5.4.
|
---|
| 695 | *
|
---|
| 696 | * \param grp The ECP group to use.
|
---|
| 697 | * This must be initialized and have group parameters
|
---|
| 698 | * set, for example through mbedtls_ecp_group_load().
|
---|
| 699 | * \param pt The point to be exported. This must be initialized.
|
---|
| 700 | * \param format The point format to use. This must be either
|
---|
| 701 | * #MBEDTLS_ECP_PF_COMPRESSED or #MBEDTLS_ECP_PF_UNCOMPRESSED.
|
---|
| 702 | * \param olen The address at which to store the length in Bytes
|
---|
| 703 | * of the data written.
|
---|
| 704 | * \param buf The target buffer. This must be a writable buffer of
|
---|
| 705 | * length \p blen Bytes.
|
---|
| 706 | * \param blen The length of the target buffer \p buf in Bytes.
|
---|
| 707 | *
|
---|
| 708 | * \return \c 0 on success.
|
---|
| 709 | * \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if the input is invalid.
|
---|
| 710 | * \return #MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL if the target buffer
|
---|
| 711 | * is too small to hold the exported point.
|
---|
| 712 | * \return Another negative error code on other kinds of failure.
|
---|
| 713 | */
|
---|
| 714 | int mbedtls_ecp_tls_write_point( const mbedtls_ecp_group *grp,
|
---|
| 715 | const mbedtls_ecp_point *pt,
|
---|
| 716 | int format, size_t *olen,
|
---|
| 717 | unsigned char *buf, size_t blen );
|
---|
| 718 |
|
---|
| 719 | /**
|
---|
| 720 | * \brief This function sets up an ECP group context
|
---|
| 721 | * from a standardized set of domain parameters.
|
---|
| 722 | *
|
---|
| 723 | * \note The index should be a value of the NamedCurve enum,
|
---|
| 724 | * as defined in <em>RFC-4492: Elliptic Curve Cryptography
|
---|
| 725 | * (ECC) Cipher Suites for Transport Layer Security (TLS)</em>,
|
---|
| 726 | * usually in the form of an \c MBEDTLS_ECP_DP_XXX macro.
|
---|
| 727 | *
|
---|
| 728 | * \param grp The group context to setup. This must be initialized.
|
---|
| 729 | * \param id The identifier of the domain parameter set to load.
|
---|
| 730 | *
|
---|
| 731 | * \return \c 0 on success.
|
---|
| 732 | * \return #MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE if \p id doesn't
|
---|
| 733 | * correspond to a known group.
|
---|
| 734 | * \return Another negative error code on other kinds of failure.
|
---|
| 735 | */
|
---|
| 736 | int mbedtls_ecp_group_load( mbedtls_ecp_group *grp, mbedtls_ecp_group_id id );
|
---|
| 737 |
|
---|
| 738 | /**
|
---|
| 739 | * \brief This function sets up an ECP group context from a TLS
|
---|
| 740 | * ECParameters record as defined in RFC 4492, Section 5.4.
|
---|
| 741 | *
|
---|
| 742 | * \note The read pointer \p buf is updated to point right after
|
---|
| 743 | * the ECParameters record on exit.
|
---|
| 744 | *
|
---|
| 745 | * \param grp The group context to setup. This must be initialized.
|
---|
| 746 | * \param buf The address of the pointer to the start of the input buffer.
|
---|
| 747 | * \param len The length of the input buffer \c *buf in Bytes.
|
---|
| 748 | *
|
---|
| 749 | * \return \c 0 on success.
|
---|
| 750 | * \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if input is invalid.
|
---|
| 751 | * \return #MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE if the group is not
|
---|
| 752 | * recognized.
|
---|
| 753 | * \return Another negative error code on other kinds of failure.
|
---|
| 754 | */
|
---|
| 755 | int mbedtls_ecp_tls_read_group( mbedtls_ecp_group *grp,
|
---|
| 756 | const unsigned char **buf, size_t len );
|
---|
| 757 |
|
---|
| 758 | /**
|
---|
| 759 | * \brief This function extracts an elliptic curve group ID from a
|
---|
| 760 | * TLS ECParameters record as defined in RFC 4492, Section 5.4.
|
---|
| 761 | *
|
---|
| 762 | * \note The read pointer \p buf is updated to point right after
|
---|
| 763 | * the ECParameters record on exit.
|
---|
| 764 | *
|
---|
| 765 | * \param grp The address at which to store the group id.
|
---|
| 766 | * This must not be \c NULL.
|
---|
| 767 | * \param buf The address of the pointer to the start of the input buffer.
|
---|
| 768 | * \param len The length of the input buffer \c *buf in Bytes.
|
---|
| 769 | *
|
---|
| 770 | * \return \c 0 on success.
|
---|
| 771 | * \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if input is invalid.
|
---|
| 772 | * \return #MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE if the group is not
|
---|
| 773 | * recognized.
|
---|
| 774 | * \return Another negative error code on other kinds of failure.
|
---|
| 775 | */
|
---|
| 776 | int mbedtls_ecp_tls_read_group_id( mbedtls_ecp_group_id *grp,
|
---|
| 777 | const unsigned char **buf,
|
---|
| 778 | size_t len );
|
---|
| 779 | /**
|
---|
| 780 | * \brief This function exports an elliptic curve as a TLS
|
---|
| 781 | * ECParameters record as defined in RFC 4492, Section 5.4.
|
---|
| 782 | *
|
---|
| 783 | * \param grp The ECP group to be exported.
|
---|
| 784 | * This must be initialized and have group parameters
|
---|
| 785 | * set, for example through mbedtls_ecp_group_load().
|
---|
| 786 | * \param olen The address at which to store the number of Bytes written.
|
---|
| 787 | * This must not be \c NULL.
|
---|
| 788 | * \param buf The buffer to write to. This must be a writable buffer
|
---|
| 789 | * of length \p blen Bytes.
|
---|
| 790 | * \param blen The length of the output buffer \p buf in Bytes.
|
---|
| 791 | *
|
---|
| 792 | * \return \c 0 on success.
|
---|
| 793 | * \return #MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL if the output
|
---|
| 794 | * buffer is too small to hold the exported group.
|
---|
| 795 | * \return Another negative error code on other kinds of failure.
|
---|
| 796 | */
|
---|
| 797 | int mbedtls_ecp_tls_write_group( const mbedtls_ecp_group *grp,
|
---|
| 798 | size_t *olen,
|
---|
| 799 | unsigned char *buf, size_t blen );
|
---|
| 800 |
|
---|
| 801 | /**
|
---|
| 802 | * \brief This function performs a scalar multiplication of a point
|
---|
| 803 | * by an integer: \p R = \p m * \p P.
|
---|
| 804 | *
|
---|
| 805 | * It is not thread-safe to use same group in multiple threads.
|
---|
| 806 | *
|
---|
| 807 | * \note To prevent timing attacks, this function
|
---|
| 808 | * executes the exact same sequence of base-field
|
---|
| 809 | * operations for any valid \p m. It avoids any if-branch or
|
---|
| 810 | * array index depending on the value of \p m.
|
---|
| 811 | *
|
---|
| 812 | * \note If \p f_rng is not NULL, it is used to randomize
|
---|
| 813 | * intermediate results to prevent potential timing attacks
|
---|
| 814 | * targeting these results. We recommend always providing
|
---|
| 815 | * a non-NULL \p f_rng. The overhead is negligible.
|
---|
| 816 | *
|
---|
| 817 | * \param grp The ECP group to use.
|
---|
| 818 | * This must be initialized and have group parameters
|
---|
| 819 | * set, for example through mbedtls_ecp_group_load().
|
---|
| 820 | * \param R The point in which to store the result of the calculation.
|
---|
| 821 | * This must be initialized.
|
---|
| 822 | * \param m The integer by which to multiply. This must be initialized.
|
---|
| 823 | * \param P The point to multiply. This must be initialized.
|
---|
| 824 | * \param f_rng The RNG function. This may be \c NULL if randomization
|
---|
| 825 | * of intermediate results isn't desired (discouraged).
|
---|
| 826 | * \param p_rng The RNG context to be passed to \p p_rng.
|
---|
| 827 | *
|
---|
| 828 | * \return \c 0 on success.
|
---|
| 829 | * \return #MBEDTLS_ERR_ECP_INVALID_KEY if \p m is not a valid private
|
---|
| 830 | * key, or \p P is not a valid public key.
|
---|
| 831 | * \return #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure.
|
---|
| 832 | * \return Another negative error code on other kinds of failure.
|
---|
| 833 | */
|
---|
| 834 | int mbedtls_ecp_mul( mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
|
---|
| 835 | const mbedtls_mpi *m, const mbedtls_ecp_point *P,
|
---|
| 836 | int (*f_rng)(void *, unsigned char *, size_t), void *p_rng );
|
---|
| 837 |
|
---|
| 838 | /**
|
---|
| 839 | * \brief This function performs multiplication of a point by
|
---|
| 840 | * an integer: \p R = \p m * \p P in a restartable way.
|
---|
| 841 | *
|
---|
| 842 | * \see mbedtls_ecp_mul()
|
---|
| 843 | *
|
---|
| 844 | * \note This function does the same as \c mbedtls_ecp_mul(), but
|
---|
| 845 | * it can return early and restart according to the limit set
|
---|
| 846 | * with \c mbedtls_ecp_set_max_ops() to reduce blocking.
|
---|
| 847 | *
|
---|
| 848 | * \param grp The ECP group to use.
|
---|
| 849 | * This must be initialized and have group parameters
|
---|
| 850 | * set, for example through mbedtls_ecp_group_load().
|
---|
| 851 | * \param R The point in which to store the result of the calculation.
|
---|
| 852 | * This must be initialized.
|
---|
| 853 | * \param m The integer by which to multiply. This must be initialized.
|
---|
| 854 | * \param P The point to multiply. This must be initialized.
|
---|
| 855 | * \param f_rng The RNG function. This may be \c NULL if randomization
|
---|
| 856 | * of intermediate results isn't desired (discouraged).
|
---|
| 857 | * \param p_rng The RNG context to be passed to \p p_rng.
|
---|
| 858 | * \param rs_ctx The restart context (NULL disables restart).
|
---|
| 859 | *
|
---|
| 860 | * \return \c 0 on success.
|
---|
| 861 | * \return #MBEDTLS_ERR_ECP_INVALID_KEY if \p m is not a valid private
|
---|
| 862 | * key, or \p P is not a valid public key.
|
---|
| 863 | * \return #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure.
|
---|
| 864 | * \return #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of
|
---|
| 865 | * operations was reached: see \c mbedtls_ecp_set_max_ops().
|
---|
| 866 | * \return Another negative error code on other kinds of failure.
|
---|
| 867 | */
|
---|
| 868 | int mbedtls_ecp_mul_restartable( mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
|
---|
| 869 | const mbedtls_mpi *m, const mbedtls_ecp_point *P,
|
---|
| 870 | int (*f_rng)(void *, unsigned char *, size_t), void *p_rng,
|
---|
| 871 | mbedtls_ecp_restart_ctx *rs_ctx );
|
---|
| 872 |
|
---|
| 873 | /**
|
---|
| 874 | * \brief This function performs multiplication and addition of two
|
---|
| 875 | * points by integers: \p R = \p m * \p P + \p n * \p Q
|
---|
| 876 | *
|
---|
| 877 | * It is not thread-safe to use same group in multiple threads.
|
---|
| 878 | *
|
---|
| 879 | * \note In contrast to mbedtls_ecp_mul(), this function does not
|
---|
| 880 | * guarantee a constant execution flow and timing.
|
---|
| 881 | *
|
---|
| 882 | * \param grp The ECP group to use.
|
---|
| 883 | * This must be initialized and have group parameters
|
---|
| 884 | * set, for example through mbedtls_ecp_group_load().
|
---|
| 885 | * \param R The point in which to store the result of the calculation.
|
---|
| 886 | * This must be initialized.
|
---|
| 887 | * \param m The integer by which to multiply \p P.
|
---|
| 888 | * This must be initialized.
|
---|
| 889 | * \param P The point to multiply by \p m. This must be initialized.
|
---|
| 890 | * \param n The integer by which to multiply \p Q.
|
---|
| 891 | * This must be initialized.
|
---|
| 892 | * \param Q The point to be multiplied by \p n.
|
---|
| 893 | * This must be initialized.
|
---|
| 894 | *
|
---|
| 895 | * \return \c 0 on success.
|
---|
| 896 | * \return #MBEDTLS_ERR_ECP_INVALID_KEY if \p m or \p n are not
|
---|
| 897 | * valid private keys, or \p P or \p Q are not valid public
|
---|
| 898 | * keys.
|
---|
| 899 | * \return #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure.
|
---|
| 900 | * \return Another negative error code on other kinds of failure.
|
---|
| 901 | */
|
---|
| 902 | int mbedtls_ecp_muladd( mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
|
---|
| 903 | const mbedtls_mpi *m, const mbedtls_ecp_point *P,
|
---|
| 904 | const mbedtls_mpi *n, const mbedtls_ecp_point *Q );
|
---|
| 905 |
|
---|
| 906 | /**
|
---|
| 907 | * \brief This function performs multiplication and addition of two
|
---|
| 908 | * points by integers: \p R = \p m * \p P + \p n * \p Q in a
|
---|
| 909 | * restartable way.
|
---|
| 910 | *
|
---|
| 911 | * \see \c mbedtls_ecp_muladd()
|
---|
| 912 | *
|
---|
| 913 | * \note This function works the same as \c mbedtls_ecp_muladd(),
|
---|
| 914 | * but it can return early and restart according to the limit
|
---|
| 915 | * set with \c mbedtls_ecp_set_max_ops() to reduce blocking.
|
---|
| 916 | *
|
---|
| 917 | * \param grp The ECP group to use.
|
---|
| 918 | * This must be initialized and have group parameters
|
---|
| 919 | * set, for example through mbedtls_ecp_group_load().
|
---|
| 920 | * \param R The point in which to store the result of the calculation.
|
---|
| 921 | * This must be initialized.
|
---|
| 922 | * \param m The integer by which to multiply \p P.
|
---|
| 923 | * This must be initialized.
|
---|
| 924 | * \param P The point to multiply by \p m. This must be initialized.
|
---|
| 925 | * \param n The integer by which to multiply \p Q.
|
---|
| 926 | * This must be initialized.
|
---|
| 927 | * \param Q The point to be multiplied by \p n.
|
---|
| 928 | * This must be initialized.
|
---|
| 929 | * \param rs_ctx The restart context (NULL disables restart).
|
---|
| 930 | *
|
---|
| 931 | * \return \c 0 on success.
|
---|
| 932 | * \return #MBEDTLS_ERR_ECP_INVALID_KEY if \p m or \p n are not
|
---|
| 933 | * valid private keys, or \p P or \p Q are not valid public
|
---|
| 934 | * keys.
|
---|
| 935 | * \return #MBEDTLS_ERR_MPI_ALLOC_FAILED on memory-allocation failure.
|
---|
| 936 | * \return #MBEDTLS_ERR_ECP_IN_PROGRESS if maximum number of
|
---|
| 937 | * operations was reached: see \c mbedtls_ecp_set_max_ops().
|
---|
| 938 | * \return Another negative error code on other kinds of failure.
|
---|
| 939 | */
|
---|
| 940 | int mbedtls_ecp_muladd_restartable(
|
---|
| 941 | mbedtls_ecp_group *grp, mbedtls_ecp_point *R,
|
---|
| 942 | const mbedtls_mpi *m, const mbedtls_ecp_point *P,
|
---|
| 943 | const mbedtls_mpi *n, const mbedtls_ecp_point *Q,
|
---|
| 944 | mbedtls_ecp_restart_ctx *rs_ctx );
|
---|
| 945 |
|
---|
| 946 | /**
|
---|
| 947 | * \brief This function checks that a point is a valid public key
|
---|
| 948 | * on this curve.
|
---|
| 949 | *
|
---|
| 950 | * It only checks that the point is non-zero, has
|
---|
| 951 | * valid coordinates and lies on the curve. It does not verify
|
---|
| 952 | * that it is indeed a multiple of \p G. This additional
|
---|
| 953 | * check is computationally more expensive, is not required
|
---|
| 954 | * by standards, and should not be necessary if the group
|
---|
| 955 | * used has a small cofactor. In particular, it is useless for
|
---|
| 956 | * the NIST groups which all have a cofactor of 1.
|
---|
| 957 | *
|
---|
| 958 | * \note This function uses bare components rather than an
|
---|
| 959 | * ::mbedtls_ecp_keypair structure, to ease use with other
|
---|
| 960 | * structures, such as ::mbedtls_ecdh_context or
|
---|
| 961 | * ::mbedtls_ecdsa_context.
|
---|
| 962 | *
|
---|
| 963 | * \param grp The ECP group the point should belong to.
|
---|
| 964 | * This must be initialized and have group parameters
|
---|
| 965 | * set, for example through mbedtls_ecp_group_load().
|
---|
| 966 | * \param pt The point to check. This must be initialized.
|
---|
| 967 | *
|
---|
| 968 | * \return \c 0 if the point is a valid public key.
|
---|
| 969 | * \return #MBEDTLS_ERR_ECP_INVALID_KEY if the point is not
|
---|
| 970 | * a valid public key for the given curve.
|
---|
| 971 | * \return Another negative error code on other kinds of failure.
|
---|
| 972 | */
|
---|
| 973 | int mbedtls_ecp_check_pubkey( const mbedtls_ecp_group *grp,
|
---|
| 974 | const mbedtls_ecp_point *pt );
|
---|
| 975 |
|
---|
| 976 | /**
|
---|
| 977 | * \brief This function checks that an \p mbedtls_mpi is a
|
---|
| 978 | * valid private key for this curve.
|
---|
| 979 | *
|
---|
| 980 | * \note This function uses bare components rather than an
|
---|
| 981 | * ::mbedtls_ecp_keypair structure to ease use with other
|
---|
| 982 | * structures, such as ::mbedtls_ecdh_context or
|
---|
| 983 | * ::mbedtls_ecdsa_context.
|
---|
| 984 | *
|
---|
| 985 | * \param grp The ECP group the private key should belong to.
|
---|
| 986 | * This must be initialized and have group parameters
|
---|
| 987 | * set, for example through mbedtls_ecp_group_load().
|
---|
| 988 | * \param d The integer to check. This must be initialized.
|
---|
| 989 | *
|
---|
| 990 | * \return \c 0 if the point is a valid private key.
|
---|
| 991 | * \return #MBEDTLS_ERR_ECP_INVALID_KEY if the point is not a valid
|
---|
| 992 | * private key for the given curve.
|
---|
| 993 | * \return Another negative error code on other kinds of failure.
|
---|
| 994 | */
|
---|
| 995 | int mbedtls_ecp_check_privkey( const mbedtls_ecp_group *grp,
|
---|
| 996 | const mbedtls_mpi *d );
|
---|
| 997 |
|
---|
| 998 | /**
|
---|
| 999 | * \brief This function generates a private key.
|
---|
| 1000 | *
|
---|
| 1001 | * \param grp The ECP group to generate a private key for.
|
---|
| 1002 | * This must be initialized and have group parameters
|
---|
| 1003 | * set, for example through mbedtls_ecp_group_load().
|
---|
| 1004 | * \param d The destination MPI (secret part). This must be initialized.
|
---|
| 1005 | * \param f_rng The RNG function. This must not be \c NULL.
|
---|
| 1006 | * \param p_rng The RNG parameter to be passed to \p f_rng. This may be
|
---|
| 1007 | * \c NULL if \p f_rng doesn't need a context argument.
|
---|
| 1008 | *
|
---|
| 1009 | * \return \c 0 on success.
|
---|
| 1010 | * \return An \c MBEDTLS_ERR_ECP_XXX or \c MBEDTLS_MPI_XXX error code
|
---|
| 1011 | * on failure.
|
---|
| 1012 | */
|
---|
| 1013 | int mbedtls_ecp_gen_privkey( const mbedtls_ecp_group *grp,
|
---|
| 1014 | mbedtls_mpi *d,
|
---|
| 1015 | int (*f_rng)(void *, unsigned char *, size_t),
|
---|
| 1016 | void *p_rng );
|
---|
| 1017 |
|
---|
| 1018 | /**
|
---|
| 1019 | * \brief This function generates a keypair with a configurable base
|
---|
| 1020 | * point.
|
---|
| 1021 | *
|
---|
| 1022 | * \note This function uses bare components rather than an
|
---|
| 1023 | * ::mbedtls_ecp_keypair structure to ease use with other
|
---|
| 1024 | * structures, such as ::mbedtls_ecdh_context or
|
---|
| 1025 | * ::mbedtls_ecdsa_context.
|
---|
| 1026 | *
|
---|
| 1027 | * \param grp The ECP group to generate a key pair for.
|
---|
| 1028 | * This must be initialized and have group parameters
|
---|
| 1029 | * set, for example through mbedtls_ecp_group_load().
|
---|
| 1030 | * \param G The base point to use. This must be initialized
|
---|
| 1031 | * and belong to \p grp. It replaces the default base
|
---|
| 1032 | * point \c grp->G used by mbedtls_ecp_gen_keypair().
|
---|
| 1033 | * \param d The destination MPI (secret part).
|
---|
| 1034 | * This must be initialized.
|
---|
| 1035 | * \param Q The destination point (public part).
|
---|
| 1036 | * This must be initialized.
|
---|
| 1037 | * \param f_rng The RNG function. This must not be \c NULL.
|
---|
| 1038 | * \param p_rng The RNG context to be passed to \p f_rng. This may
|
---|
| 1039 | * be \c NULL if \p f_rng doesn't need a context argument.
|
---|
| 1040 | *
|
---|
| 1041 | * \return \c 0 on success.
|
---|
| 1042 | * \return An \c MBEDTLS_ERR_ECP_XXX or \c MBEDTLS_MPI_XXX error code
|
---|
| 1043 | * on failure.
|
---|
| 1044 | */
|
---|
| 1045 | int mbedtls_ecp_gen_keypair_base( mbedtls_ecp_group *grp,
|
---|
| 1046 | const mbedtls_ecp_point *G,
|
---|
| 1047 | mbedtls_mpi *d, mbedtls_ecp_point *Q,
|
---|
| 1048 | int (*f_rng)(void *, unsigned char *, size_t),
|
---|
| 1049 | void *p_rng );
|
---|
| 1050 |
|
---|
| 1051 | /**
|
---|
| 1052 | * \brief This function generates an ECP keypair.
|
---|
| 1053 | *
|
---|
| 1054 | * \note This function uses bare components rather than an
|
---|
| 1055 | * ::mbedtls_ecp_keypair structure to ease use with other
|
---|
| 1056 | * structures, such as ::mbedtls_ecdh_context or
|
---|
| 1057 | * ::mbedtls_ecdsa_context.
|
---|
| 1058 | *
|
---|
| 1059 | * \param grp The ECP group to generate a key pair for.
|
---|
| 1060 | * This must be initialized and have group parameters
|
---|
| 1061 | * set, for example through mbedtls_ecp_group_load().
|
---|
| 1062 | * \param d The destination MPI (secret part).
|
---|
| 1063 | * This must be initialized.
|
---|
| 1064 | * \param Q The destination point (public part).
|
---|
| 1065 | * This must be initialized.
|
---|
| 1066 | * \param f_rng The RNG function. This must not be \c NULL.
|
---|
| 1067 | * \param p_rng The RNG context to be passed to \p f_rng. This may
|
---|
| 1068 | * be \c NULL if \p f_rng doesn't need a context argument.
|
---|
| 1069 | *
|
---|
| 1070 | * \return \c 0 on success.
|
---|
| 1071 | * \return An \c MBEDTLS_ERR_ECP_XXX or \c MBEDTLS_MPI_XXX error code
|
---|
| 1072 | * on failure.
|
---|
| 1073 | */
|
---|
| 1074 | int mbedtls_ecp_gen_keypair( mbedtls_ecp_group *grp, mbedtls_mpi *d,
|
---|
| 1075 | mbedtls_ecp_point *Q,
|
---|
| 1076 | int (*f_rng)(void *, unsigned char *, size_t),
|
---|
| 1077 | void *p_rng );
|
---|
| 1078 |
|
---|
| 1079 | /**
|
---|
| 1080 | * \brief This function generates an ECP key.
|
---|
| 1081 | *
|
---|
| 1082 | * \param grp_id The ECP group identifier.
|
---|
| 1083 | * \param key The destination key. This must be initialized.
|
---|
| 1084 | * \param f_rng The RNG function to use. This must not be \c NULL.
|
---|
| 1085 | * \param p_rng The RNG context to be passed to \p f_rng. This may
|
---|
| 1086 | * be \c NULL if \p f_rng doesn't need a context argument.
|
---|
| 1087 | *
|
---|
| 1088 | * \return \c 0 on success.
|
---|
| 1089 | * \return An \c MBEDTLS_ERR_ECP_XXX or \c MBEDTLS_MPI_XXX error code
|
---|
| 1090 | * on failure.
|
---|
| 1091 | */
|
---|
| 1092 | int mbedtls_ecp_gen_key( mbedtls_ecp_group_id grp_id, mbedtls_ecp_keypair *key,
|
---|
| 1093 | int (*f_rng)(void *, unsigned char *, size_t),
|
---|
| 1094 | void *p_rng );
|
---|
| 1095 |
|
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| 1096 | /**
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| 1097 | * \brief This function checks that the keypair objects
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| 1098 | * \p pub and \p prv have the same group and the
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| 1099 | * same public point, and that the private key in
|
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| 1100 | * \p prv is consistent with the public key.
|
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| 1101 | *
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| 1102 | * \param pub The keypair structure holding the public key. This
|
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| 1103 | * must be initialized. If it contains a private key, that
|
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| 1104 | * part is ignored.
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| 1105 | * \param prv The keypair structure holding the full keypair.
|
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| 1106 | * This must be initialized.
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| 1107 | *
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| 1108 | * \return \c 0 on success, meaning that the keys are valid and match.
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| 1109 | * \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if the keys are invalid or do not match.
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| 1110 | * \return An \c MBEDTLS_ERR_ECP_XXX or an \c MBEDTLS_ERR_MPI_XXX
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| 1111 | * error code on calculation failure.
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| 1112 | */
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| 1113 | int mbedtls_ecp_check_pub_priv( const mbedtls_ecp_keypair *pub,
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| 1114 | const mbedtls_ecp_keypair *prv );
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| 1115 |
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| 1116 | #if defined(MBEDTLS_SELF_TEST)
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| 1117 |
|
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| 1118 | /**
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| 1119 | * \brief The ECP checkup routine.
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| 1120 | *
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| 1121 | * \return \c 0 on success.
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| 1122 | * \return \c 1 on failure.
|
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| 1123 | */
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| 1124 | int mbedtls_ecp_self_test( int verbose );
|
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| 1125 |
|
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| 1126 | #endif /* MBEDTLS_SELF_TEST */
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| 1127 |
|
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| 1128 | #ifdef __cplusplus
|
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| 1129 | }
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| 1130 | #endif
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| 1131 |
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| 1132 | #endif /* ecp.h */
|
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