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
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371 | * SSL module). For functions that accept a "restart context"
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372 | * argument, passing NULL disables restart and makes the
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373 | * function equivalent to the function with the same name
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374 | * with \c _restartable removed. For functions in the ECDH
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375 | * module, restart is disabled unless the function accepts
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376 | * an "ECDH context" argument and
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377 | * mbedtls_ecdh_enable_restart() was previously called on
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378 | * that context. For function in the SSL module, restart is
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379 | * only enabled for specific sides and key exchanges
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380 | * (currently only for clients and ECDHE-ECDSA).
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381 | *
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382 | * \param max_ops Maximum number of basic operations done in a row.
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383 | * Default: 0 (unlimited).
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384 | * Lower (non-zero) values mean ECC functions will block for
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385 | * a lesser maximum amount of time.
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386 | *
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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 |
|
---|
1096 | /**
|
---|
1097 | * \brief This function checks that the keypair objects
|
---|
1098 | * \p pub and \p prv have the same group and the
|
---|
1099 | * same public point, and that the private key in
|
---|
1100 | * \p prv is consistent with the public key.
|
---|
1101 | *
|
---|
1102 | * \param pub The keypair structure holding the public key. This
|
---|
1103 | * must be initialized. If it contains a private key, that
|
---|
1104 | * part is ignored.
|
---|
1105 | * \param prv The keypair structure holding the full keypair.
|
---|
1106 | * This must be initialized.
|
---|
1107 | *
|
---|
1108 | * \return \c 0 on success, meaning that the keys are valid and match.
|
---|
1109 | * \return #MBEDTLS_ERR_ECP_BAD_INPUT_DATA if the keys are invalid or do not match.
|
---|
1110 | * \return An \c MBEDTLS_ERR_ECP_XXX or an \c MBEDTLS_ERR_MPI_XXX
|
---|
1111 | * error code on calculation failure.
|
---|
1112 | */
|
---|
1113 | int mbedtls_ecp_check_pub_priv( const mbedtls_ecp_keypair *pub,
|
---|
1114 | const mbedtls_ecp_keypair *prv );
|
---|
1115 |
|
---|
1116 | #if defined(MBEDTLS_SELF_TEST)
|
---|
1117 |
|
---|
1118 | /**
|
---|
1119 | * \brief The ECP checkup routine.
|
---|
1120 | *
|
---|
1121 | * \return \c 0 on success.
|
---|
1122 | * \return \c 1 on failure.
|
---|
1123 | */
|
---|
1124 | int mbedtls_ecp_self_test( int verbose );
|
---|
1125 |
|
---|
1126 | #endif /* MBEDTLS_SELF_TEST */
|
---|
1127 |
|
---|
1128 | #ifdef __cplusplus
|
---|
1129 | }
|
---|
1130 | #endif
|
---|
1131 |
|
---|
1132 | #endif /* ecp.h */
|
---|