1 | /*
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2 | * The RSA public-key cryptosystem
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3 | *
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4 | * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
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5 | * SPDX-License-Identifier: Apache-2.0
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6 | *
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7 | * Licensed under the Apache License, Version 2.0 (the "License"); you may
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8 | * not use this file except in compliance with the License.
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9 | * You may obtain a copy of the License at
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10 | *
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11 | * http://www.apache.org/licenses/LICENSE-2.0
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12 | *
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13 | * Unless required by applicable law or agreed to in writing, software
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14 | * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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15 | * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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16 | * See the License for the specific language governing permissions and
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17 | * limitations under the License.
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18 | *
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19 | * This file is part of mbed TLS (https://tls.mbed.org)
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20 | */
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21 |
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22 | /*
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23 | * The following sources were referenced in the design of this implementation
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24 | * of the RSA algorithm:
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25 | *
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26 | * [1] A method for obtaining digital signatures and public-key cryptosystems
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27 | * R Rivest, A Shamir, and L Adleman
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28 | * http://people.csail.mit.edu/rivest/pubs.html#RSA78
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29 | *
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30 | * [2] Handbook of Applied Cryptography - 1997, Chapter 8
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31 | * Menezes, van Oorschot and Vanstone
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32 | *
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33 | * [3] Malware Guard Extension: Using SGX to Conceal Cache Attacks
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34 | * Michael Schwarz, Samuel Weiser, Daniel Gruss, Clémentine Maurice and
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35 | * Stefan Mangard
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36 | * https://arxiv.org/abs/1702.08719v2
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37 | *
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38 | */
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39 |
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40 | #if !defined(MBEDTLS_CONFIG_FILE)
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41 | #include "mbedtls/config.h"
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42 | #else
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43 | #include MBEDTLS_CONFIG_FILE
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44 | #endif
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45 |
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46 | #if defined(MBEDTLS_RSA_C)
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47 |
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48 | #include "mbedtls/rsa.h"
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49 | #include "mbedtls/rsa_internal.h"
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50 | #include "mbedtls/oid.h"
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51 | #include "mbedtls/platform_util.h"
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52 |
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53 | #include <string.h>
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54 |
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55 | #if defined(MBEDTLS_PKCS1_V21)
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56 | #include "mbedtls/md.h"
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57 | #endif
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58 |
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59 | #if defined(MBEDTLS_PKCS1_V15) && !defined(__OpenBSD__)
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60 | #include <stdlib.h>
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61 | #endif
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62 |
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63 | #if defined(MBEDTLS_PLATFORM_C)
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64 | #include "mbedtls/platform.h"
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65 | #else
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66 | #include <stdio.h>
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67 | #define mbedtls_printf printf
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68 | #define mbedtls_calloc calloc
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69 | #define mbedtls_free free
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70 | #endif
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71 |
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72 | #if !defined(MBEDTLS_RSA_ALT)
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73 |
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74 | /* Parameter validation macros */
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75 | #define RSA_VALIDATE_RET( cond ) \
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76 | MBEDTLS_INTERNAL_VALIDATE_RET( cond, MBEDTLS_ERR_RSA_BAD_INPUT_DATA )
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77 | #define RSA_VALIDATE( cond ) \
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78 | MBEDTLS_INTERNAL_VALIDATE( cond )
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79 |
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80 | #if defined(MBEDTLS_PKCS1_V15)
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81 | /* constant-time buffer comparison */
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82 | static inline int mbedtls_safer_memcmp( const void *a, const void *b, size_t n )
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83 | {
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84 | size_t i;
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85 | const unsigned char *A = (const unsigned char *) a;
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86 | const unsigned char *B = (const unsigned char *) b;
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87 | unsigned char diff = 0;
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88 |
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89 | for( i = 0; i < n; i++ )
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90 | diff |= A[i] ^ B[i];
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91 |
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92 | return( diff );
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93 | }
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94 | #endif /* MBEDTLS_PKCS1_V15 */
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95 |
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96 | int mbedtls_rsa_import( mbedtls_rsa_context *ctx,
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97 | const mbedtls_mpi *N,
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98 | const mbedtls_mpi *P, const mbedtls_mpi *Q,
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99 | const mbedtls_mpi *D, const mbedtls_mpi *E )
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100 | {
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101 | int ret;
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102 | RSA_VALIDATE_RET( ctx != NULL );
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103 |
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104 | if( ( N != NULL && ( ret = mbedtls_mpi_copy( &ctx->N, N ) ) != 0 ) ||
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105 | ( P != NULL && ( ret = mbedtls_mpi_copy( &ctx->P, P ) ) != 0 ) ||
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106 | ( Q != NULL && ( ret = mbedtls_mpi_copy( &ctx->Q, Q ) ) != 0 ) ||
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107 | ( D != NULL && ( ret = mbedtls_mpi_copy( &ctx->D, D ) ) != 0 ) ||
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108 | ( E != NULL && ( ret = mbedtls_mpi_copy( &ctx->E, E ) ) != 0 ) )
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109 | {
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110 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA + ret );
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111 | }
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112 |
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113 | if( N != NULL )
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114 | ctx->len = mbedtls_mpi_size( &ctx->N );
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115 |
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116 | return( 0 );
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117 | }
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118 |
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119 | int mbedtls_rsa_import_raw( mbedtls_rsa_context *ctx,
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120 | unsigned char const *N, size_t N_len,
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121 | unsigned char const *P, size_t P_len,
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122 | unsigned char const *Q, size_t Q_len,
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123 | unsigned char const *D, size_t D_len,
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124 | unsigned char const *E, size_t E_len )
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125 | {
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126 | int ret = 0;
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127 | RSA_VALIDATE_RET( ctx != NULL );
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128 |
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129 | if( N != NULL )
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130 | {
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131 | MBEDTLS_MPI_CHK( mbedtls_mpi_read_binary( &ctx->N, N, N_len ) );
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132 | ctx->len = mbedtls_mpi_size( &ctx->N );
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133 | }
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134 |
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135 | if( P != NULL )
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136 | MBEDTLS_MPI_CHK( mbedtls_mpi_read_binary( &ctx->P, P, P_len ) );
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137 |
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138 | if( Q != NULL )
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139 | MBEDTLS_MPI_CHK( mbedtls_mpi_read_binary( &ctx->Q, Q, Q_len ) );
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140 |
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141 | if( D != NULL )
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142 | MBEDTLS_MPI_CHK( mbedtls_mpi_read_binary( &ctx->D, D, D_len ) );
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143 |
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144 | if( E != NULL )
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145 | MBEDTLS_MPI_CHK( mbedtls_mpi_read_binary( &ctx->E, E, E_len ) );
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146 |
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147 | cleanup:
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148 |
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149 | if( ret != 0 )
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150 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA + ret );
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151 |
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152 | return( 0 );
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153 | }
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154 |
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155 | /*
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156 | * Checks whether the context fields are set in such a way
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157 | * that the RSA primitives will be able to execute without error.
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158 | * It does *not* make guarantees for consistency of the parameters.
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159 | */
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160 | static int rsa_check_context( mbedtls_rsa_context const *ctx, int is_priv,
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161 | int blinding_needed )
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162 | {
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163 | #if !defined(MBEDTLS_RSA_NO_CRT)
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164 | /* blinding_needed is only used for NO_CRT to decide whether
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165 | * P,Q need to be present or not. */
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166 | ((void) blinding_needed);
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167 | #endif
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168 |
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169 | if( ctx->len != mbedtls_mpi_size( &ctx->N ) ||
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170 | ctx->len > MBEDTLS_MPI_MAX_SIZE )
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171 | {
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172 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
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173 | }
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174 |
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175 | /*
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176 | * 1. Modular exponentiation needs positive, odd moduli.
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177 | */
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178 |
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179 | /* Modular exponentiation wrt. N is always used for
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180 | * RSA public key operations. */
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181 | if( mbedtls_mpi_cmp_int( &ctx->N, 0 ) <= 0 ||
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182 | mbedtls_mpi_get_bit( &ctx->N, 0 ) == 0 )
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183 | {
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184 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
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185 | }
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186 |
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187 | #if !defined(MBEDTLS_RSA_NO_CRT)
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188 | /* Modular exponentiation for P and Q is only
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189 | * used for private key operations and if CRT
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190 | * is used. */
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191 | if( is_priv &&
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192 | ( mbedtls_mpi_cmp_int( &ctx->P, 0 ) <= 0 ||
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193 | mbedtls_mpi_get_bit( &ctx->P, 0 ) == 0 ||
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194 | mbedtls_mpi_cmp_int( &ctx->Q, 0 ) <= 0 ||
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195 | mbedtls_mpi_get_bit( &ctx->Q, 0 ) == 0 ) )
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196 | {
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197 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
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198 | }
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199 | #endif /* !MBEDTLS_RSA_NO_CRT */
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200 |
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201 | /*
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202 | * 2. Exponents must be positive
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203 | */
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204 |
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205 | /* Always need E for public key operations */
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206 | if( mbedtls_mpi_cmp_int( &ctx->E, 0 ) <= 0 )
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207 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
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208 |
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209 | #if defined(MBEDTLS_RSA_NO_CRT)
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210 | /* For private key operations, use D or DP & DQ
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211 | * as (unblinded) exponents. */
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212 | if( is_priv && mbedtls_mpi_cmp_int( &ctx->D, 0 ) <= 0 )
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213 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
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214 | #else
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215 | if( is_priv &&
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216 | ( mbedtls_mpi_cmp_int( &ctx->DP, 0 ) <= 0 ||
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217 | mbedtls_mpi_cmp_int( &ctx->DQ, 0 ) <= 0 ) )
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218 | {
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219 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
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220 | }
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221 | #endif /* MBEDTLS_RSA_NO_CRT */
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222 |
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223 | /* Blinding shouldn't make exponents negative either,
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224 | * so check that P, Q >= 1 if that hasn't yet been
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225 | * done as part of 1. */
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226 | #if defined(MBEDTLS_RSA_NO_CRT)
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227 | if( is_priv && blinding_needed &&
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228 | ( mbedtls_mpi_cmp_int( &ctx->P, 0 ) <= 0 ||
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229 | mbedtls_mpi_cmp_int( &ctx->Q, 0 ) <= 0 ) )
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230 | {
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231 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
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232 | }
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233 | #endif
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234 |
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235 | /* It wouldn't lead to an error if it wasn't satisfied,
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236 | * but check for QP >= 1 nonetheless. */
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237 | #if !defined(MBEDTLS_RSA_NO_CRT)
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238 | if( is_priv &&
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239 | mbedtls_mpi_cmp_int( &ctx->QP, 0 ) <= 0 )
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240 | {
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241 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
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242 | }
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243 | #endif
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244 |
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245 | return( 0 );
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246 | }
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247 |
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248 | int mbedtls_rsa_complete( mbedtls_rsa_context *ctx )
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249 | {
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250 | int ret = 0;
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251 | int have_N, have_P, have_Q, have_D, have_E;
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252 | int n_missing, pq_missing, d_missing, is_pub, is_priv;
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253 |
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254 | RSA_VALIDATE_RET( ctx != NULL );
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255 |
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256 | have_N = ( mbedtls_mpi_cmp_int( &ctx->N, 0 ) != 0 );
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257 | have_P = ( mbedtls_mpi_cmp_int( &ctx->P, 0 ) != 0 );
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258 | have_Q = ( mbedtls_mpi_cmp_int( &ctx->Q, 0 ) != 0 );
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259 | have_D = ( mbedtls_mpi_cmp_int( &ctx->D, 0 ) != 0 );
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260 | have_E = ( mbedtls_mpi_cmp_int( &ctx->E, 0 ) != 0 );
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261 |
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262 | /*
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263 | * Check whether provided parameters are enough
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264 | * to deduce all others. The following incomplete
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265 | * parameter sets for private keys are supported:
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266 | *
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267 | * (1) P, Q missing.
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268 | * (2) D and potentially N missing.
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269 | *
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270 | */
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271 |
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272 | n_missing = have_P && have_Q && have_D && have_E;
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273 | pq_missing = have_N && !have_P && !have_Q && have_D && have_E;
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274 | d_missing = have_P && have_Q && !have_D && have_E;
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275 | is_pub = have_N && !have_P && !have_Q && !have_D && have_E;
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276 |
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277 | /* These three alternatives are mutually exclusive */
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278 | is_priv = n_missing || pq_missing || d_missing;
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279 |
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280 | if( !is_priv && !is_pub )
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281 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
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282 |
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283 | /*
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284 | * Step 1: Deduce N if P, Q are provided.
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285 | */
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286 |
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287 | if( !have_N && have_P && have_Q )
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288 | {
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289 | if( ( ret = mbedtls_mpi_mul_mpi( &ctx->N, &ctx->P,
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290 | &ctx->Q ) ) != 0 )
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291 | {
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292 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA + ret );
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293 | }
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294 |
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295 | ctx->len = mbedtls_mpi_size( &ctx->N );
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296 | }
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297 |
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298 | /*
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299 | * Step 2: Deduce and verify all remaining core parameters.
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300 | */
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301 |
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302 | if( pq_missing )
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303 | {
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304 | ret = mbedtls_rsa_deduce_primes( &ctx->N, &ctx->E, &ctx->D,
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305 | &ctx->P, &ctx->Q );
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306 | if( ret != 0 )
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307 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA + ret );
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308 |
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309 | }
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310 | else if( d_missing )
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311 | {
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312 | if( ( ret = mbedtls_rsa_deduce_private_exponent( &ctx->P,
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313 | &ctx->Q,
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314 | &ctx->E,
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315 | &ctx->D ) ) != 0 )
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316 | {
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317 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA + ret );
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318 | }
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319 | }
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320 |
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321 | /*
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322 | * Step 3: Deduce all additional parameters specific
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323 | * to our current RSA implementation.
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324 | */
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325 |
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326 | #if !defined(MBEDTLS_RSA_NO_CRT)
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327 | if( is_priv )
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328 | {
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329 | ret = mbedtls_rsa_deduce_crt( &ctx->P, &ctx->Q, &ctx->D,
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330 | &ctx->DP, &ctx->DQ, &ctx->QP );
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331 | if( ret != 0 )
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332 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA + ret );
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333 | }
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334 | #endif /* MBEDTLS_RSA_NO_CRT */
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335 |
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336 | /*
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337 | * Step 3: Basic sanity checks
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338 | */
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339 |
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340 | return( rsa_check_context( ctx, is_priv, 1 ) );
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341 | }
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342 |
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343 | int mbedtls_rsa_export_raw( const mbedtls_rsa_context *ctx,
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344 | unsigned char *N, size_t N_len,
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345 | unsigned char *P, size_t P_len,
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346 | unsigned char *Q, size_t Q_len,
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347 | unsigned char *D, size_t D_len,
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348 | unsigned char *E, size_t E_len )
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349 | {
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350 | int ret = 0;
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351 | int is_priv;
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352 | RSA_VALIDATE_RET( ctx != NULL );
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353 |
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354 | /* Check if key is private or public */
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355 | is_priv =
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356 | mbedtls_mpi_cmp_int( &ctx->N, 0 ) != 0 &&
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357 | mbedtls_mpi_cmp_int( &ctx->P, 0 ) != 0 &&
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358 | mbedtls_mpi_cmp_int( &ctx->Q, 0 ) != 0 &&
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359 | mbedtls_mpi_cmp_int( &ctx->D, 0 ) != 0 &&
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360 | mbedtls_mpi_cmp_int( &ctx->E, 0 ) != 0;
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361 |
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362 | if( !is_priv )
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363 | {
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364 | /* If we're trying to export private parameters for a public key,
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365 | * something must be wrong. */
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366 | if( P != NULL || Q != NULL || D != NULL )
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367 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
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368 |
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369 | }
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370 |
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371 | if( N != NULL )
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372 | MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary( &ctx->N, N, N_len ) );
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373 |
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374 | if( P != NULL )
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375 | MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary( &ctx->P, P, P_len ) );
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376 |
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377 | if( Q != NULL )
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378 | MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary( &ctx->Q, Q, Q_len ) );
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379 |
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380 | if( D != NULL )
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381 | MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary( &ctx->D, D, D_len ) );
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382 |
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383 | if( E != NULL )
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384 | MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary( &ctx->E, E, E_len ) );
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385 |
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386 | cleanup:
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387 |
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388 | return( ret );
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389 | }
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390 |
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391 | int mbedtls_rsa_export( const mbedtls_rsa_context *ctx,
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392 | mbedtls_mpi *N, mbedtls_mpi *P, mbedtls_mpi *Q,
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393 | mbedtls_mpi *D, mbedtls_mpi *E )
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394 | {
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395 | int ret;
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396 | int is_priv;
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397 | RSA_VALIDATE_RET( ctx != NULL );
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398 |
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399 | /* Check if key is private or public */
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400 | is_priv =
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401 | mbedtls_mpi_cmp_int( &ctx->N, 0 ) != 0 &&
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402 | mbedtls_mpi_cmp_int( &ctx->P, 0 ) != 0 &&
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403 | mbedtls_mpi_cmp_int( &ctx->Q, 0 ) != 0 &&
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404 | mbedtls_mpi_cmp_int( &ctx->D, 0 ) != 0 &&
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405 | mbedtls_mpi_cmp_int( &ctx->E, 0 ) != 0;
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406 |
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407 | if( !is_priv )
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408 | {
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409 | /* If we're trying to export private parameters for a public key,
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410 | * something must be wrong. */
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411 | if( P != NULL || Q != NULL || D != NULL )
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412 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
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413 |
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414 | }
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415 |
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416 | /* Export all requested core parameters. */
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417 |
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418 | if( ( N != NULL && ( ret = mbedtls_mpi_copy( N, &ctx->N ) ) != 0 ) ||
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419 | ( P != NULL && ( ret = mbedtls_mpi_copy( P, &ctx->P ) ) != 0 ) ||
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420 | ( Q != NULL && ( ret = mbedtls_mpi_copy( Q, &ctx->Q ) ) != 0 ) ||
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421 | ( D != NULL && ( ret = mbedtls_mpi_copy( D, &ctx->D ) ) != 0 ) ||
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422 | ( E != NULL && ( ret = mbedtls_mpi_copy( E, &ctx->E ) ) != 0 ) )
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423 | {
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424 | return( ret );
|
---|
425 | }
|
---|
426 |
|
---|
427 | return( 0 );
|
---|
428 | }
|
---|
429 |
|
---|
430 | /*
|
---|
431 | * Export CRT parameters
|
---|
432 | * This must also be implemented if CRT is not used, for being able to
|
---|
433 | * write DER encoded RSA keys. The helper function mbedtls_rsa_deduce_crt
|
---|
434 | * can be used in this case.
|
---|
435 | */
|
---|
436 | int mbedtls_rsa_export_crt( const mbedtls_rsa_context *ctx,
|
---|
437 | mbedtls_mpi *DP, mbedtls_mpi *DQ, mbedtls_mpi *QP )
|
---|
438 | {
|
---|
439 | int ret;
|
---|
440 | int is_priv;
|
---|
441 | RSA_VALIDATE_RET( ctx != NULL );
|
---|
442 |
|
---|
443 | /* Check if key is private or public */
|
---|
444 | is_priv =
|
---|
445 | mbedtls_mpi_cmp_int( &ctx->N, 0 ) != 0 &&
|
---|
446 | mbedtls_mpi_cmp_int( &ctx->P, 0 ) != 0 &&
|
---|
447 | mbedtls_mpi_cmp_int( &ctx->Q, 0 ) != 0 &&
|
---|
448 | mbedtls_mpi_cmp_int( &ctx->D, 0 ) != 0 &&
|
---|
449 | mbedtls_mpi_cmp_int( &ctx->E, 0 ) != 0;
|
---|
450 |
|
---|
451 | if( !is_priv )
|
---|
452 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
453 |
|
---|
454 | #if !defined(MBEDTLS_RSA_NO_CRT)
|
---|
455 | /* Export all requested blinding parameters. */
|
---|
456 | if( ( DP != NULL && ( ret = mbedtls_mpi_copy( DP, &ctx->DP ) ) != 0 ) ||
|
---|
457 | ( DQ != NULL && ( ret = mbedtls_mpi_copy( DQ, &ctx->DQ ) ) != 0 ) ||
|
---|
458 | ( QP != NULL && ( ret = mbedtls_mpi_copy( QP, &ctx->QP ) ) != 0 ) )
|
---|
459 | {
|
---|
460 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA + ret );
|
---|
461 | }
|
---|
462 | #else
|
---|
463 | if( ( ret = mbedtls_rsa_deduce_crt( &ctx->P, &ctx->Q, &ctx->D,
|
---|
464 | DP, DQ, QP ) ) != 0 )
|
---|
465 | {
|
---|
466 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA + ret );
|
---|
467 | }
|
---|
468 | #endif
|
---|
469 |
|
---|
470 | return( 0 );
|
---|
471 | }
|
---|
472 |
|
---|
473 | /*
|
---|
474 | * Initialize an RSA context
|
---|
475 | */
|
---|
476 | void mbedtls_rsa_init( mbedtls_rsa_context *ctx,
|
---|
477 | int padding,
|
---|
478 | int hash_id )
|
---|
479 | {
|
---|
480 | RSA_VALIDATE( ctx != NULL );
|
---|
481 | RSA_VALIDATE( padding == MBEDTLS_RSA_PKCS_V15 ||
|
---|
482 | padding == MBEDTLS_RSA_PKCS_V21 );
|
---|
483 |
|
---|
484 | memset( ctx, 0, sizeof( mbedtls_rsa_context ) );
|
---|
485 |
|
---|
486 | mbedtls_rsa_set_padding( ctx, padding, hash_id );
|
---|
487 |
|
---|
488 | #if defined(MBEDTLS_THREADING_C)
|
---|
489 | mbedtls_mutex_init( &ctx->mutex );
|
---|
490 | #endif
|
---|
491 | }
|
---|
492 |
|
---|
493 | /*
|
---|
494 | * Set padding for an existing RSA context
|
---|
495 | */
|
---|
496 | void mbedtls_rsa_set_padding( mbedtls_rsa_context *ctx, int padding,
|
---|
497 | int hash_id )
|
---|
498 | {
|
---|
499 | RSA_VALIDATE( ctx != NULL );
|
---|
500 | RSA_VALIDATE( padding == MBEDTLS_RSA_PKCS_V15 ||
|
---|
501 | padding == MBEDTLS_RSA_PKCS_V21 );
|
---|
502 |
|
---|
503 | ctx->padding = padding;
|
---|
504 | ctx->hash_id = hash_id;
|
---|
505 | }
|
---|
506 |
|
---|
507 | /*
|
---|
508 | * Get length in bytes of RSA modulus
|
---|
509 | */
|
---|
510 |
|
---|
511 | size_t mbedtls_rsa_get_len( const mbedtls_rsa_context *ctx )
|
---|
512 | {
|
---|
513 | return( ctx->len );
|
---|
514 | }
|
---|
515 |
|
---|
516 |
|
---|
517 | #if defined(MBEDTLS_GENPRIME)
|
---|
518 |
|
---|
519 | /*
|
---|
520 | * Generate an RSA keypair
|
---|
521 | *
|
---|
522 | * This generation method follows the RSA key pair generation procedure of
|
---|
523 | * FIPS 186-4 if 2^16 < exponent < 2^256 and nbits = 2048 or nbits = 3072.
|
---|
524 | */
|
---|
525 | int mbedtls_rsa_gen_key( mbedtls_rsa_context *ctx,
|
---|
526 | int (*f_rng)(void *, unsigned char *, size_t),
|
---|
527 | void *p_rng,
|
---|
528 | unsigned int nbits, int exponent )
|
---|
529 | {
|
---|
530 | int ret;
|
---|
531 | mbedtls_mpi H, G, L;
|
---|
532 | int prime_quality = 0;
|
---|
533 | RSA_VALIDATE_RET( ctx != NULL );
|
---|
534 | RSA_VALIDATE_RET( f_rng != NULL );
|
---|
535 |
|
---|
536 | if( nbits < 128 || exponent < 3 || nbits % 2 != 0 )
|
---|
537 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
538 |
|
---|
539 | /*
|
---|
540 | * If the modulus is 1024 bit long or shorter, then the security strength of
|
---|
541 | * the RSA algorithm is less than or equal to 80 bits and therefore an error
|
---|
542 | * rate of 2^-80 is sufficient.
|
---|
543 | */
|
---|
544 | if( nbits > 1024 )
|
---|
545 | prime_quality = MBEDTLS_MPI_GEN_PRIME_FLAG_LOW_ERR;
|
---|
546 |
|
---|
547 | mbedtls_mpi_init( &H );
|
---|
548 | mbedtls_mpi_init( &G );
|
---|
549 | mbedtls_mpi_init( &L );
|
---|
550 |
|
---|
551 | /*
|
---|
552 | * find primes P and Q with Q < P so that:
|
---|
553 | * 1. |P-Q| > 2^( nbits / 2 - 100 )
|
---|
554 | * 2. GCD( E, (P-1)*(Q-1) ) == 1
|
---|
555 | * 3. E^-1 mod LCM(P-1, Q-1) > 2^( nbits / 2 )
|
---|
556 | */
|
---|
557 | MBEDTLS_MPI_CHK( mbedtls_mpi_lset( &ctx->E, exponent ) );
|
---|
558 |
|
---|
559 | do
|
---|
560 | {
|
---|
561 | MBEDTLS_MPI_CHK( mbedtls_mpi_gen_prime( &ctx->P, nbits >> 1,
|
---|
562 | prime_quality, f_rng, p_rng ) );
|
---|
563 |
|
---|
564 | MBEDTLS_MPI_CHK( mbedtls_mpi_gen_prime( &ctx->Q, nbits >> 1,
|
---|
565 | prime_quality, f_rng, p_rng ) );
|
---|
566 |
|
---|
567 | /* make sure the difference between p and q is not too small (FIPS 186-4 §B.3.3 step 5.4) */
|
---|
568 | MBEDTLS_MPI_CHK( mbedtls_mpi_sub_mpi( &H, &ctx->P, &ctx->Q ) );
|
---|
569 | if( mbedtls_mpi_bitlen( &H ) <= ( ( nbits >= 200 ) ? ( ( nbits >> 1 ) - 99 ) : 0 ) )
|
---|
570 | continue;
|
---|
571 |
|
---|
572 | /* not required by any standards, but some users rely on the fact that P > Q */
|
---|
573 | if( H.s < 0 )
|
---|
574 | mbedtls_mpi_swap( &ctx->P, &ctx->Q );
|
---|
575 |
|
---|
576 | /* Temporarily replace P,Q by P-1, Q-1 */
|
---|
577 | MBEDTLS_MPI_CHK( mbedtls_mpi_sub_int( &ctx->P, &ctx->P, 1 ) );
|
---|
578 | MBEDTLS_MPI_CHK( mbedtls_mpi_sub_int( &ctx->Q, &ctx->Q, 1 ) );
|
---|
579 | MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &H, &ctx->P, &ctx->Q ) );
|
---|
580 |
|
---|
581 | /* check GCD( E, (P-1)*(Q-1) ) == 1 (FIPS 186-4 §B.3.1 criterion 2(a)) */
|
---|
582 | MBEDTLS_MPI_CHK( mbedtls_mpi_gcd( &G, &ctx->E, &H ) );
|
---|
583 | if( mbedtls_mpi_cmp_int( &G, 1 ) != 0 )
|
---|
584 | continue;
|
---|
585 |
|
---|
586 | /* compute smallest possible D = E^-1 mod LCM(P-1, Q-1) (FIPS 186-4 §B.3.1 criterion 3(b)) */
|
---|
587 | MBEDTLS_MPI_CHK( mbedtls_mpi_gcd( &G, &ctx->P, &ctx->Q ) );
|
---|
588 | MBEDTLS_MPI_CHK( mbedtls_mpi_div_mpi( &L, NULL, &H, &G ) );
|
---|
589 | MBEDTLS_MPI_CHK( mbedtls_mpi_inv_mod( &ctx->D, &ctx->E, &L ) );
|
---|
590 |
|
---|
591 | if( mbedtls_mpi_bitlen( &ctx->D ) <= ( ( nbits + 1 ) / 2 ) ) // (FIPS 186-4 §B.3.1 criterion 3(a))
|
---|
592 | continue;
|
---|
593 |
|
---|
594 | break;
|
---|
595 | }
|
---|
596 | while( 1 );
|
---|
597 |
|
---|
598 | /* Restore P,Q */
|
---|
599 | MBEDTLS_MPI_CHK( mbedtls_mpi_add_int( &ctx->P, &ctx->P, 1 ) );
|
---|
600 | MBEDTLS_MPI_CHK( mbedtls_mpi_add_int( &ctx->Q, &ctx->Q, 1 ) );
|
---|
601 |
|
---|
602 | MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &ctx->N, &ctx->P, &ctx->Q ) );
|
---|
603 |
|
---|
604 | ctx->len = mbedtls_mpi_size( &ctx->N );
|
---|
605 |
|
---|
606 | #if !defined(MBEDTLS_RSA_NO_CRT)
|
---|
607 | /*
|
---|
608 | * DP = D mod (P - 1)
|
---|
609 | * DQ = D mod (Q - 1)
|
---|
610 | * QP = Q^-1 mod P
|
---|
611 | */
|
---|
612 | MBEDTLS_MPI_CHK( mbedtls_rsa_deduce_crt( &ctx->P, &ctx->Q, &ctx->D,
|
---|
613 | &ctx->DP, &ctx->DQ, &ctx->QP ) );
|
---|
614 | #endif /* MBEDTLS_RSA_NO_CRT */
|
---|
615 |
|
---|
616 | /* Double-check */
|
---|
617 | MBEDTLS_MPI_CHK( mbedtls_rsa_check_privkey( ctx ) );
|
---|
618 |
|
---|
619 | cleanup:
|
---|
620 |
|
---|
621 | mbedtls_mpi_free( &H );
|
---|
622 | mbedtls_mpi_free( &G );
|
---|
623 | mbedtls_mpi_free( &L );
|
---|
624 |
|
---|
625 | if( ret != 0 )
|
---|
626 | {
|
---|
627 | mbedtls_rsa_free( ctx );
|
---|
628 | return( MBEDTLS_ERR_RSA_KEY_GEN_FAILED + ret );
|
---|
629 | }
|
---|
630 |
|
---|
631 | return( 0 );
|
---|
632 | }
|
---|
633 |
|
---|
634 | #endif /* MBEDTLS_GENPRIME */
|
---|
635 |
|
---|
636 | /*
|
---|
637 | * Check a public RSA key
|
---|
638 | */
|
---|
639 | int mbedtls_rsa_check_pubkey( const mbedtls_rsa_context *ctx )
|
---|
640 | {
|
---|
641 | RSA_VALIDATE_RET( ctx != NULL );
|
---|
642 |
|
---|
643 | if( rsa_check_context( ctx, 0 /* public */, 0 /* no blinding */ ) != 0 )
|
---|
644 | return( MBEDTLS_ERR_RSA_KEY_CHECK_FAILED );
|
---|
645 |
|
---|
646 | if( mbedtls_mpi_bitlen( &ctx->N ) < 128 )
|
---|
647 | {
|
---|
648 | return( MBEDTLS_ERR_RSA_KEY_CHECK_FAILED );
|
---|
649 | }
|
---|
650 |
|
---|
651 | if( mbedtls_mpi_get_bit( &ctx->E, 0 ) == 0 ||
|
---|
652 | mbedtls_mpi_bitlen( &ctx->E ) < 2 ||
|
---|
653 | mbedtls_mpi_cmp_mpi( &ctx->E, &ctx->N ) >= 0 )
|
---|
654 | {
|
---|
655 | return( MBEDTLS_ERR_RSA_KEY_CHECK_FAILED );
|
---|
656 | }
|
---|
657 |
|
---|
658 | return( 0 );
|
---|
659 | }
|
---|
660 |
|
---|
661 | /*
|
---|
662 | * Check for the consistency of all fields in an RSA private key context
|
---|
663 | */
|
---|
664 | int mbedtls_rsa_check_privkey( const mbedtls_rsa_context *ctx )
|
---|
665 | {
|
---|
666 | RSA_VALIDATE_RET( ctx != NULL );
|
---|
667 |
|
---|
668 | if( mbedtls_rsa_check_pubkey( ctx ) != 0 ||
|
---|
669 | rsa_check_context( ctx, 1 /* private */, 1 /* blinding */ ) != 0 )
|
---|
670 | {
|
---|
671 | return( MBEDTLS_ERR_RSA_KEY_CHECK_FAILED );
|
---|
672 | }
|
---|
673 |
|
---|
674 | if( mbedtls_rsa_validate_params( &ctx->N, &ctx->P, &ctx->Q,
|
---|
675 | &ctx->D, &ctx->E, NULL, NULL ) != 0 )
|
---|
676 | {
|
---|
677 | return( MBEDTLS_ERR_RSA_KEY_CHECK_FAILED );
|
---|
678 | }
|
---|
679 |
|
---|
680 | #if !defined(MBEDTLS_RSA_NO_CRT)
|
---|
681 | else if( mbedtls_rsa_validate_crt( &ctx->P, &ctx->Q, &ctx->D,
|
---|
682 | &ctx->DP, &ctx->DQ, &ctx->QP ) != 0 )
|
---|
683 | {
|
---|
684 | return( MBEDTLS_ERR_RSA_KEY_CHECK_FAILED );
|
---|
685 | }
|
---|
686 | #endif
|
---|
687 |
|
---|
688 | return( 0 );
|
---|
689 | }
|
---|
690 |
|
---|
691 | /*
|
---|
692 | * Check if contexts holding a public and private key match
|
---|
693 | */
|
---|
694 | int mbedtls_rsa_check_pub_priv( const mbedtls_rsa_context *pub,
|
---|
695 | const mbedtls_rsa_context *prv )
|
---|
696 | {
|
---|
697 | RSA_VALIDATE_RET( pub != NULL );
|
---|
698 | RSA_VALIDATE_RET( prv != NULL );
|
---|
699 |
|
---|
700 | if( mbedtls_rsa_check_pubkey( pub ) != 0 ||
|
---|
701 | mbedtls_rsa_check_privkey( prv ) != 0 )
|
---|
702 | {
|
---|
703 | return( MBEDTLS_ERR_RSA_KEY_CHECK_FAILED );
|
---|
704 | }
|
---|
705 |
|
---|
706 | if( mbedtls_mpi_cmp_mpi( &pub->N, &prv->N ) != 0 ||
|
---|
707 | mbedtls_mpi_cmp_mpi( &pub->E, &prv->E ) != 0 )
|
---|
708 | {
|
---|
709 | return( MBEDTLS_ERR_RSA_KEY_CHECK_FAILED );
|
---|
710 | }
|
---|
711 |
|
---|
712 | return( 0 );
|
---|
713 | }
|
---|
714 |
|
---|
715 | /*
|
---|
716 | * Do an RSA public key operation
|
---|
717 | */
|
---|
718 | int mbedtls_rsa_public( mbedtls_rsa_context *ctx,
|
---|
719 | const unsigned char *input,
|
---|
720 | unsigned char *output )
|
---|
721 | {
|
---|
722 | int ret;
|
---|
723 | size_t olen;
|
---|
724 | mbedtls_mpi T;
|
---|
725 | RSA_VALIDATE_RET( ctx != NULL );
|
---|
726 | RSA_VALIDATE_RET( input != NULL );
|
---|
727 | RSA_VALIDATE_RET( output != NULL );
|
---|
728 |
|
---|
729 | if( rsa_check_context( ctx, 0 /* public */, 0 /* no blinding */ ) )
|
---|
730 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
731 |
|
---|
732 | mbedtls_mpi_init( &T );
|
---|
733 |
|
---|
734 | #if defined(MBEDTLS_THREADING_C)
|
---|
735 | if( ( ret = mbedtls_mutex_lock( &ctx->mutex ) ) != 0 )
|
---|
736 | return( ret );
|
---|
737 | #endif
|
---|
738 |
|
---|
739 | MBEDTLS_MPI_CHK( mbedtls_mpi_read_binary( &T, input, ctx->len ) );
|
---|
740 |
|
---|
741 | if( mbedtls_mpi_cmp_mpi( &T, &ctx->N ) >= 0 )
|
---|
742 | {
|
---|
743 | ret = MBEDTLS_ERR_MPI_BAD_INPUT_DATA;
|
---|
744 | goto cleanup;
|
---|
745 | }
|
---|
746 |
|
---|
747 | olen = ctx->len;
|
---|
748 | MBEDTLS_MPI_CHK( mbedtls_mpi_exp_mod( &T, &T, &ctx->E, &ctx->N, &ctx->RN ) );
|
---|
749 | MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary( &T, output, olen ) );
|
---|
750 |
|
---|
751 | cleanup:
|
---|
752 | #if defined(MBEDTLS_THREADING_C)
|
---|
753 | if( mbedtls_mutex_unlock( &ctx->mutex ) != 0 )
|
---|
754 | return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
|
---|
755 | #endif
|
---|
756 |
|
---|
757 | mbedtls_mpi_free( &T );
|
---|
758 |
|
---|
759 | if( ret != 0 )
|
---|
760 | return( MBEDTLS_ERR_RSA_PUBLIC_FAILED + ret );
|
---|
761 |
|
---|
762 | return( 0 );
|
---|
763 | }
|
---|
764 |
|
---|
765 | /*
|
---|
766 | * Generate or update blinding values, see section 10 of:
|
---|
767 | * KOCHER, Paul C. Timing attacks on implementations of Diffie-Hellman, RSA,
|
---|
768 | * DSS, and other systems. In : Advances in Cryptology-CRYPTO'96. Springer
|
---|
769 | * Berlin Heidelberg, 1996. p. 104-113.
|
---|
770 | */
|
---|
771 | static int rsa_prepare_blinding( mbedtls_rsa_context *ctx,
|
---|
772 | int (*f_rng)(void *, unsigned char *, size_t), void *p_rng )
|
---|
773 | {
|
---|
774 | int ret, count = 0;
|
---|
775 |
|
---|
776 | if( ctx->Vf.p != NULL )
|
---|
777 | {
|
---|
778 | /* We already have blinding values, just update them by squaring */
|
---|
779 | MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &ctx->Vi, &ctx->Vi, &ctx->Vi ) );
|
---|
780 | MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &ctx->Vi, &ctx->Vi, &ctx->N ) );
|
---|
781 | MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &ctx->Vf, &ctx->Vf, &ctx->Vf ) );
|
---|
782 | MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &ctx->Vf, &ctx->Vf, &ctx->N ) );
|
---|
783 |
|
---|
784 | goto cleanup;
|
---|
785 | }
|
---|
786 |
|
---|
787 | /* Unblinding value: Vf = random number, invertible mod N */
|
---|
788 | do {
|
---|
789 | if( count++ > 10 )
|
---|
790 | return( MBEDTLS_ERR_RSA_RNG_FAILED );
|
---|
791 |
|
---|
792 | MBEDTLS_MPI_CHK( mbedtls_mpi_fill_random( &ctx->Vf, ctx->len - 1, f_rng, p_rng ) );
|
---|
793 | MBEDTLS_MPI_CHK( mbedtls_mpi_gcd( &ctx->Vi, &ctx->Vf, &ctx->N ) );
|
---|
794 | } while( mbedtls_mpi_cmp_int( &ctx->Vi, 1 ) != 0 );
|
---|
795 |
|
---|
796 | /* Blinding value: Vi = Vf^(-e) mod N */
|
---|
797 | MBEDTLS_MPI_CHK( mbedtls_mpi_inv_mod( &ctx->Vi, &ctx->Vf, &ctx->N ) );
|
---|
798 | MBEDTLS_MPI_CHK( mbedtls_mpi_exp_mod( &ctx->Vi, &ctx->Vi, &ctx->E, &ctx->N, &ctx->RN ) );
|
---|
799 |
|
---|
800 |
|
---|
801 | cleanup:
|
---|
802 | return( ret );
|
---|
803 | }
|
---|
804 |
|
---|
805 | /*
|
---|
806 | * Exponent blinding supposed to prevent side-channel attacks using multiple
|
---|
807 | * traces of measurements to recover the RSA key. The more collisions are there,
|
---|
808 | * the more bits of the key can be recovered. See [3].
|
---|
809 | *
|
---|
810 | * Collecting n collisions with m bit long blinding value requires 2^(m-m/n)
|
---|
811 | * observations on avarage.
|
---|
812 | *
|
---|
813 | * For example with 28 byte blinding to achieve 2 collisions the adversary has
|
---|
814 | * to make 2^112 observations on avarage.
|
---|
815 | *
|
---|
816 | * (With the currently (as of 2017 April) known best algorithms breaking 2048
|
---|
817 | * bit RSA requires approximately as much time as trying out 2^112 random keys.
|
---|
818 | * Thus in this sense with 28 byte blinding the security is not reduced by
|
---|
819 | * side-channel attacks like the one in [3])
|
---|
820 | *
|
---|
821 | * This countermeasure does not help if the key recovery is possible with a
|
---|
822 | * single trace.
|
---|
823 | */
|
---|
824 | #define RSA_EXPONENT_BLINDING 28
|
---|
825 |
|
---|
826 | /*
|
---|
827 | * Do an RSA private key operation
|
---|
828 | */
|
---|
829 | int mbedtls_rsa_private( mbedtls_rsa_context *ctx,
|
---|
830 | int (*f_rng)(void *, unsigned char *, size_t),
|
---|
831 | void *p_rng,
|
---|
832 | const unsigned char *input,
|
---|
833 | unsigned char *output )
|
---|
834 | {
|
---|
835 | int ret;
|
---|
836 | size_t olen;
|
---|
837 |
|
---|
838 | /* Temporary holding the result */
|
---|
839 | mbedtls_mpi T;
|
---|
840 |
|
---|
841 | /* Temporaries holding P-1, Q-1 and the
|
---|
842 | * exponent blinding factor, respectively. */
|
---|
843 | mbedtls_mpi P1, Q1, R;
|
---|
844 |
|
---|
845 | #if !defined(MBEDTLS_RSA_NO_CRT)
|
---|
846 | /* Temporaries holding the results mod p resp. mod q. */
|
---|
847 | mbedtls_mpi TP, TQ;
|
---|
848 |
|
---|
849 | /* Temporaries holding the blinded exponents for
|
---|
850 | * the mod p resp. mod q computation (if used). */
|
---|
851 | mbedtls_mpi DP_blind, DQ_blind;
|
---|
852 |
|
---|
853 | /* Pointers to actual exponents to be used - either the unblinded
|
---|
854 | * or the blinded ones, depending on the presence of a PRNG. */
|
---|
855 | mbedtls_mpi *DP = &ctx->DP;
|
---|
856 | mbedtls_mpi *DQ = &ctx->DQ;
|
---|
857 | #else
|
---|
858 | /* Temporary holding the blinded exponent (if used). */
|
---|
859 | mbedtls_mpi D_blind;
|
---|
860 |
|
---|
861 | /* Pointer to actual exponent to be used - either the unblinded
|
---|
862 | * or the blinded one, depending on the presence of a PRNG. */
|
---|
863 | mbedtls_mpi *D = &ctx->D;
|
---|
864 | #endif /* MBEDTLS_RSA_NO_CRT */
|
---|
865 |
|
---|
866 | /* Temporaries holding the initial input and the double
|
---|
867 | * checked result; should be the same in the end. */
|
---|
868 | mbedtls_mpi I, C;
|
---|
869 |
|
---|
870 | RSA_VALIDATE_RET( ctx != NULL );
|
---|
871 | RSA_VALIDATE_RET( input != NULL );
|
---|
872 | RSA_VALIDATE_RET( output != NULL );
|
---|
873 |
|
---|
874 | if( rsa_check_context( ctx, 1 /* private key checks */,
|
---|
875 | f_rng != NULL /* blinding y/n */ ) != 0 )
|
---|
876 | {
|
---|
877 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
878 | }
|
---|
879 |
|
---|
880 | #if defined(MBEDTLS_THREADING_C)
|
---|
881 | if( ( ret = mbedtls_mutex_lock( &ctx->mutex ) ) != 0 )
|
---|
882 | return( ret );
|
---|
883 | #endif
|
---|
884 |
|
---|
885 | /* MPI Initialization */
|
---|
886 | mbedtls_mpi_init( &T );
|
---|
887 |
|
---|
888 | mbedtls_mpi_init( &P1 );
|
---|
889 | mbedtls_mpi_init( &Q1 );
|
---|
890 | mbedtls_mpi_init( &R );
|
---|
891 |
|
---|
892 | if( f_rng != NULL )
|
---|
893 | {
|
---|
894 | #if defined(MBEDTLS_RSA_NO_CRT)
|
---|
895 | mbedtls_mpi_init( &D_blind );
|
---|
896 | #else
|
---|
897 | mbedtls_mpi_init( &DP_blind );
|
---|
898 | mbedtls_mpi_init( &DQ_blind );
|
---|
899 | #endif
|
---|
900 | }
|
---|
901 |
|
---|
902 | #if !defined(MBEDTLS_RSA_NO_CRT)
|
---|
903 | mbedtls_mpi_init( &TP ); mbedtls_mpi_init( &TQ );
|
---|
904 | #endif
|
---|
905 |
|
---|
906 | mbedtls_mpi_init( &I );
|
---|
907 | mbedtls_mpi_init( &C );
|
---|
908 |
|
---|
909 | /* End of MPI initialization */
|
---|
910 |
|
---|
911 | MBEDTLS_MPI_CHK( mbedtls_mpi_read_binary( &T, input, ctx->len ) );
|
---|
912 | if( mbedtls_mpi_cmp_mpi( &T, &ctx->N ) >= 0 )
|
---|
913 | {
|
---|
914 | ret = MBEDTLS_ERR_MPI_BAD_INPUT_DATA;
|
---|
915 | goto cleanup;
|
---|
916 | }
|
---|
917 |
|
---|
918 | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &I, &T ) );
|
---|
919 |
|
---|
920 | if( f_rng != NULL )
|
---|
921 | {
|
---|
922 | /*
|
---|
923 | * Blinding
|
---|
924 | * T = T * Vi mod N
|
---|
925 | */
|
---|
926 | MBEDTLS_MPI_CHK( rsa_prepare_blinding( ctx, f_rng, p_rng ) );
|
---|
927 | MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &T, &T, &ctx->Vi ) );
|
---|
928 | MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &T, &T, &ctx->N ) );
|
---|
929 |
|
---|
930 | /*
|
---|
931 | * Exponent blinding
|
---|
932 | */
|
---|
933 | MBEDTLS_MPI_CHK( mbedtls_mpi_sub_int( &P1, &ctx->P, 1 ) );
|
---|
934 | MBEDTLS_MPI_CHK( mbedtls_mpi_sub_int( &Q1, &ctx->Q, 1 ) );
|
---|
935 |
|
---|
936 | #if defined(MBEDTLS_RSA_NO_CRT)
|
---|
937 | /*
|
---|
938 | * D_blind = ( P - 1 ) * ( Q - 1 ) * R + D
|
---|
939 | */
|
---|
940 | MBEDTLS_MPI_CHK( mbedtls_mpi_fill_random( &R, RSA_EXPONENT_BLINDING,
|
---|
941 | f_rng, p_rng ) );
|
---|
942 | MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &D_blind, &P1, &Q1 ) );
|
---|
943 | MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &D_blind, &D_blind, &R ) );
|
---|
944 | MBEDTLS_MPI_CHK( mbedtls_mpi_add_mpi( &D_blind, &D_blind, &ctx->D ) );
|
---|
945 |
|
---|
946 | D = &D_blind;
|
---|
947 | #else
|
---|
948 | /*
|
---|
949 | * DP_blind = ( P - 1 ) * R + DP
|
---|
950 | */
|
---|
951 | MBEDTLS_MPI_CHK( mbedtls_mpi_fill_random( &R, RSA_EXPONENT_BLINDING,
|
---|
952 | f_rng, p_rng ) );
|
---|
953 | MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &DP_blind, &P1, &R ) );
|
---|
954 | MBEDTLS_MPI_CHK( mbedtls_mpi_add_mpi( &DP_blind, &DP_blind,
|
---|
955 | &ctx->DP ) );
|
---|
956 |
|
---|
957 | DP = &DP_blind;
|
---|
958 |
|
---|
959 | /*
|
---|
960 | * DQ_blind = ( Q - 1 ) * R + DQ
|
---|
961 | */
|
---|
962 | MBEDTLS_MPI_CHK( mbedtls_mpi_fill_random( &R, RSA_EXPONENT_BLINDING,
|
---|
963 | f_rng, p_rng ) );
|
---|
964 | MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &DQ_blind, &Q1, &R ) );
|
---|
965 | MBEDTLS_MPI_CHK( mbedtls_mpi_add_mpi( &DQ_blind, &DQ_blind,
|
---|
966 | &ctx->DQ ) );
|
---|
967 |
|
---|
968 | DQ = &DQ_blind;
|
---|
969 | #endif /* MBEDTLS_RSA_NO_CRT */
|
---|
970 | }
|
---|
971 |
|
---|
972 | #if defined(MBEDTLS_RSA_NO_CRT)
|
---|
973 | MBEDTLS_MPI_CHK( mbedtls_mpi_exp_mod( &T, &T, D, &ctx->N, &ctx->RN ) );
|
---|
974 | #else
|
---|
975 | /*
|
---|
976 | * Faster decryption using the CRT
|
---|
977 | *
|
---|
978 | * TP = input ^ dP mod P
|
---|
979 | * TQ = input ^ dQ mod Q
|
---|
980 | */
|
---|
981 |
|
---|
982 | MBEDTLS_MPI_CHK( mbedtls_mpi_exp_mod( &TP, &T, DP, &ctx->P, &ctx->RP ) );
|
---|
983 | MBEDTLS_MPI_CHK( mbedtls_mpi_exp_mod( &TQ, &T, DQ, &ctx->Q, &ctx->RQ ) );
|
---|
984 |
|
---|
985 | /*
|
---|
986 | * T = (TP - TQ) * (Q^-1 mod P) mod P
|
---|
987 | */
|
---|
988 | MBEDTLS_MPI_CHK( mbedtls_mpi_sub_mpi( &T, &TP, &TQ ) );
|
---|
989 | MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &TP, &T, &ctx->QP ) );
|
---|
990 | MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &T, &TP, &ctx->P ) );
|
---|
991 |
|
---|
992 | /*
|
---|
993 | * T = TQ + T * Q
|
---|
994 | */
|
---|
995 | MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &TP, &T, &ctx->Q ) );
|
---|
996 | MBEDTLS_MPI_CHK( mbedtls_mpi_add_mpi( &T, &TQ, &TP ) );
|
---|
997 | #endif /* MBEDTLS_RSA_NO_CRT */
|
---|
998 |
|
---|
999 | if( f_rng != NULL )
|
---|
1000 | {
|
---|
1001 | /*
|
---|
1002 | * Unblind
|
---|
1003 | * T = T * Vf mod N
|
---|
1004 | */
|
---|
1005 | MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &T, &T, &ctx->Vf ) );
|
---|
1006 | MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &T, &T, &ctx->N ) );
|
---|
1007 | }
|
---|
1008 |
|
---|
1009 | /* Verify the result to prevent glitching attacks. */
|
---|
1010 | MBEDTLS_MPI_CHK( mbedtls_mpi_exp_mod( &C, &T, &ctx->E,
|
---|
1011 | &ctx->N, &ctx->RN ) );
|
---|
1012 | if( mbedtls_mpi_cmp_mpi( &C, &I ) != 0 )
|
---|
1013 | {
|
---|
1014 | ret = MBEDTLS_ERR_RSA_VERIFY_FAILED;
|
---|
1015 | goto cleanup;
|
---|
1016 | }
|
---|
1017 |
|
---|
1018 | olen = ctx->len;
|
---|
1019 | MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary( &T, output, olen ) );
|
---|
1020 |
|
---|
1021 | cleanup:
|
---|
1022 | #if defined(MBEDTLS_THREADING_C)
|
---|
1023 | if( mbedtls_mutex_unlock( &ctx->mutex ) != 0 )
|
---|
1024 | return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
|
---|
1025 | #endif
|
---|
1026 |
|
---|
1027 | mbedtls_mpi_free( &P1 );
|
---|
1028 | mbedtls_mpi_free( &Q1 );
|
---|
1029 | mbedtls_mpi_free( &R );
|
---|
1030 |
|
---|
1031 | if( f_rng != NULL )
|
---|
1032 | {
|
---|
1033 | #if defined(MBEDTLS_RSA_NO_CRT)
|
---|
1034 | mbedtls_mpi_free( &D_blind );
|
---|
1035 | #else
|
---|
1036 | mbedtls_mpi_free( &DP_blind );
|
---|
1037 | mbedtls_mpi_free( &DQ_blind );
|
---|
1038 | #endif
|
---|
1039 | }
|
---|
1040 |
|
---|
1041 | mbedtls_mpi_free( &T );
|
---|
1042 |
|
---|
1043 | #if !defined(MBEDTLS_RSA_NO_CRT)
|
---|
1044 | mbedtls_mpi_free( &TP ); mbedtls_mpi_free( &TQ );
|
---|
1045 | #endif
|
---|
1046 |
|
---|
1047 | mbedtls_mpi_free( &C );
|
---|
1048 | mbedtls_mpi_free( &I );
|
---|
1049 |
|
---|
1050 | if( ret != 0 )
|
---|
1051 | return( MBEDTLS_ERR_RSA_PRIVATE_FAILED + ret );
|
---|
1052 |
|
---|
1053 | return( 0 );
|
---|
1054 | }
|
---|
1055 |
|
---|
1056 | #if defined(MBEDTLS_PKCS1_V21)
|
---|
1057 | /**
|
---|
1058 | * Generate and apply the MGF1 operation (from PKCS#1 v2.1) to a buffer.
|
---|
1059 | *
|
---|
1060 | * \param dst buffer to mask
|
---|
1061 | * \param dlen length of destination buffer
|
---|
1062 | * \param src source of the mask generation
|
---|
1063 | * \param slen length of the source buffer
|
---|
1064 | * \param md_ctx message digest context to use
|
---|
1065 | */
|
---|
1066 | static int mgf_mask( unsigned char *dst, size_t dlen, unsigned char *src,
|
---|
1067 | size_t slen, mbedtls_md_context_t *md_ctx )
|
---|
1068 | {
|
---|
1069 | unsigned char mask[MBEDTLS_MD_MAX_SIZE];
|
---|
1070 | unsigned char counter[4];
|
---|
1071 | unsigned char *p;
|
---|
1072 | unsigned int hlen;
|
---|
1073 | size_t i, use_len;
|
---|
1074 | int ret = 0;
|
---|
1075 |
|
---|
1076 | memset( mask, 0, MBEDTLS_MD_MAX_SIZE );
|
---|
1077 | memset( counter, 0, 4 );
|
---|
1078 |
|
---|
1079 | hlen = mbedtls_md_get_size( md_ctx->md_info );
|
---|
1080 |
|
---|
1081 | /* Generate and apply dbMask */
|
---|
1082 | p = dst;
|
---|
1083 |
|
---|
1084 | while( dlen > 0 )
|
---|
1085 | {
|
---|
1086 | use_len = hlen;
|
---|
1087 | if( dlen < hlen )
|
---|
1088 | use_len = dlen;
|
---|
1089 |
|
---|
1090 | if( ( ret = mbedtls_md_starts( md_ctx ) ) != 0 )
|
---|
1091 | goto exit;
|
---|
1092 | if( ( ret = mbedtls_md_update( md_ctx, src, slen ) ) != 0 )
|
---|
1093 | goto exit;
|
---|
1094 | if( ( ret = mbedtls_md_update( md_ctx, counter, 4 ) ) != 0 )
|
---|
1095 | goto exit;
|
---|
1096 | if( ( ret = mbedtls_md_finish( md_ctx, mask ) ) != 0 )
|
---|
1097 | goto exit;
|
---|
1098 |
|
---|
1099 | for( i = 0; i < use_len; ++i )
|
---|
1100 | *p++ ^= mask[i];
|
---|
1101 |
|
---|
1102 | counter[3]++;
|
---|
1103 |
|
---|
1104 | dlen -= use_len;
|
---|
1105 | }
|
---|
1106 |
|
---|
1107 | exit:
|
---|
1108 | mbedtls_platform_zeroize( mask, sizeof( mask ) );
|
---|
1109 |
|
---|
1110 | return( ret );
|
---|
1111 | }
|
---|
1112 | #endif /* MBEDTLS_PKCS1_V21 */
|
---|
1113 |
|
---|
1114 | #if defined(MBEDTLS_PKCS1_V21)
|
---|
1115 | /*
|
---|
1116 | * Implementation of the PKCS#1 v2.1 RSAES-OAEP-ENCRYPT function
|
---|
1117 | */
|
---|
1118 | int mbedtls_rsa_rsaes_oaep_encrypt( mbedtls_rsa_context *ctx,
|
---|
1119 | int (*f_rng)(void *, unsigned char *, size_t),
|
---|
1120 | void *p_rng,
|
---|
1121 | int mode,
|
---|
1122 | const unsigned char *label, size_t label_len,
|
---|
1123 | size_t ilen,
|
---|
1124 | const unsigned char *input,
|
---|
1125 | unsigned char *output )
|
---|
1126 | {
|
---|
1127 | size_t olen;
|
---|
1128 | int ret;
|
---|
1129 | unsigned char *p = output;
|
---|
1130 | unsigned int hlen;
|
---|
1131 | const mbedtls_md_info_t *md_info;
|
---|
1132 | mbedtls_md_context_t md_ctx;
|
---|
1133 |
|
---|
1134 | RSA_VALIDATE_RET( ctx != NULL );
|
---|
1135 | RSA_VALIDATE_RET( mode == MBEDTLS_RSA_PRIVATE ||
|
---|
1136 | mode == MBEDTLS_RSA_PUBLIC );
|
---|
1137 | RSA_VALIDATE_RET( output != NULL );
|
---|
1138 | RSA_VALIDATE_RET( input != NULL );
|
---|
1139 | RSA_VALIDATE_RET( label_len == 0 || label != NULL );
|
---|
1140 |
|
---|
1141 | if( mode == MBEDTLS_RSA_PRIVATE && ctx->padding != MBEDTLS_RSA_PKCS_V21 )
|
---|
1142 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
1143 |
|
---|
1144 | if( f_rng == NULL )
|
---|
1145 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
1146 |
|
---|
1147 | md_info = mbedtls_md_info_from_type( (mbedtls_md_type_t) ctx->hash_id );
|
---|
1148 | if( md_info == NULL )
|
---|
1149 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
1150 |
|
---|
1151 | olen = ctx->len;
|
---|
1152 | hlen = mbedtls_md_get_size( md_info );
|
---|
1153 |
|
---|
1154 | /* first comparison checks for overflow */
|
---|
1155 | if( ilen + 2 * hlen + 2 < ilen || olen < ilen + 2 * hlen + 2 )
|
---|
1156 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
1157 |
|
---|
1158 | memset( output, 0, olen );
|
---|
1159 |
|
---|
1160 | *p++ = 0;
|
---|
1161 |
|
---|
1162 | /* Generate a random octet string seed */
|
---|
1163 | if( ( ret = f_rng( p_rng, p, hlen ) ) != 0 )
|
---|
1164 | return( MBEDTLS_ERR_RSA_RNG_FAILED + ret );
|
---|
1165 |
|
---|
1166 | p += hlen;
|
---|
1167 |
|
---|
1168 | /* Construct DB */
|
---|
1169 | if( ( ret = mbedtls_md( md_info, label, label_len, p ) ) != 0 )
|
---|
1170 | return( ret );
|
---|
1171 | p += hlen;
|
---|
1172 | p += olen - 2 * hlen - 2 - ilen;
|
---|
1173 | *p++ = 1;
|
---|
1174 | memcpy( p, input, ilen );
|
---|
1175 |
|
---|
1176 | mbedtls_md_init( &md_ctx );
|
---|
1177 | if( ( ret = mbedtls_md_setup( &md_ctx, md_info, 0 ) ) != 0 )
|
---|
1178 | goto exit;
|
---|
1179 |
|
---|
1180 | /* maskedDB: Apply dbMask to DB */
|
---|
1181 | if( ( ret = mgf_mask( output + hlen + 1, olen - hlen - 1, output + 1, hlen,
|
---|
1182 | &md_ctx ) ) != 0 )
|
---|
1183 | goto exit;
|
---|
1184 |
|
---|
1185 | /* maskedSeed: Apply seedMask to seed */
|
---|
1186 | if( ( ret = mgf_mask( output + 1, hlen, output + hlen + 1, olen - hlen - 1,
|
---|
1187 | &md_ctx ) ) != 0 )
|
---|
1188 | goto exit;
|
---|
1189 |
|
---|
1190 | exit:
|
---|
1191 | mbedtls_md_free( &md_ctx );
|
---|
1192 |
|
---|
1193 | if( ret != 0 )
|
---|
1194 | return( ret );
|
---|
1195 |
|
---|
1196 | return( ( mode == MBEDTLS_RSA_PUBLIC )
|
---|
1197 | ? mbedtls_rsa_public( ctx, output, output )
|
---|
1198 | : mbedtls_rsa_private( ctx, f_rng, p_rng, output, output ) );
|
---|
1199 | }
|
---|
1200 | #endif /* MBEDTLS_PKCS1_V21 */
|
---|
1201 |
|
---|
1202 | #if defined(MBEDTLS_PKCS1_V15)
|
---|
1203 | /*
|
---|
1204 | * Implementation of the PKCS#1 v2.1 RSAES-PKCS1-V1_5-ENCRYPT function
|
---|
1205 | */
|
---|
1206 | int mbedtls_rsa_rsaes_pkcs1_v15_encrypt( mbedtls_rsa_context *ctx,
|
---|
1207 | int (*f_rng)(void *, unsigned char *, size_t),
|
---|
1208 | void *p_rng,
|
---|
1209 | int mode, size_t ilen,
|
---|
1210 | const unsigned char *input,
|
---|
1211 | unsigned char *output )
|
---|
1212 | {
|
---|
1213 | size_t nb_pad, olen;
|
---|
1214 | int ret;
|
---|
1215 | unsigned char *p = output;
|
---|
1216 |
|
---|
1217 | RSA_VALIDATE_RET( ctx != NULL );
|
---|
1218 | RSA_VALIDATE_RET( mode == MBEDTLS_RSA_PRIVATE ||
|
---|
1219 | mode == MBEDTLS_RSA_PUBLIC );
|
---|
1220 | RSA_VALIDATE_RET( output != NULL );
|
---|
1221 | RSA_VALIDATE_RET( input != NULL );
|
---|
1222 |
|
---|
1223 | if( mode == MBEDTLS_RSA_PRIVATE && ctx->padding != MBEDTLS_RSA_PKCS_V15 )
|
---|
1224 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
1225 |
|
---|
1226 | olen = ctx->len;
|
---|
1227 |
|
---|
1228 | /* first comparison checks for overflow */
|
---|
1229 | if( ilen + 11 < ilen || olen < ilen + 11 )
|
---|
1230 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
1231 |
|
---|
1232 | nb_pad = olen - 3 - ilen;
|
---|
1233 |
|
---|
1234 | *p++ = 0;
|
---|
1235 | if( mode == MBEDTLS_RSA_PUBLIC )
|
---|
1236 | {
|
---|
1237 | if( f_rng == NULL )
|
---|
1238 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
1239 |
|
---|
1240 | *p++ = MBEDTLS_RSA_CRYPT;
|
---|
1241 |
|
---|
1242 | while( nb_pad-- > 0 )
|
---|
1243 | {
|
---|
1244 | int rng_dl = 100;
|
---|
1245 |
|
---|
1246 | do {
|
---|
1247 | ret = f_rng( p_rng, p, 1 );
|
---|
1248 | } while( *p == 0 && --rng_dl && ret == 0 );
|
---|
1249 |
|
---|
1250 | /* Check if RNG failed to generate data */
|
---|
1251 | if( rng_dl == 0 || ret != 0 )
|
---|
1252 | return( MBEDTLS_ERR_RSA_RNG_FAILED + ret );
|
---|
1253 |
|
---|
1254 | p++;
|
---|
1255 | }
|
---|
1256 | }
|
---|
1257 | else
|
---|
1258 | {
|
---|
1259 | *p++ = MBEDTLS_RSA_SIGN;
|
---|
1260 |
|
---|
1261 | while( nb_pad-- > 0 )
|
---|
1262 | *p++ = 0xFF;
|
---|
1263 | }
|
---|
1264 |
|
---|
1265 | *p++ = 0;
|
---|
1266 | memcpy( p, input, ilen );
|
---|
1267 |
|
---|
1268 | return( ( mode == MBEDTLS_RSA_PUBLIC )
|
---|
1269 | ? mbedtls_rsa_public( ctx, output, output )
|
---|
1270 | : mbedtls_rsa_private( ctx, f_rng, p_rng, output, output ) );
|
---|
1271 | }
|
---|
1272 | #endif /* MBEDTLS_PKCS1_V15 */
|
---|
1273 |
|
---|
1274 | /*
|
---|
1275 | * Add the message padding, then do an RSA operation
|
---|
1276 | */
|
---|
1277 | int mbedtls_rsa_pkcs1_encrypt( mbedtls_rsa_context *ctx,
|
---|
1278 | int (*f_rng)(void *, unsigned char *, size_t),
|
---|
1279 | void *p_rng,
|
---|
1280 | int mode, size_t ilen,
|
---|
1281 | const unsigned char *input,
|
---|
1282 | unsigned char *output )
|
---|
1283 | {
|
---|
1284 | RSA_VALIDATE_RET( ctx != NULL );
|
---|
1285 | RSA_VALIDATE_RET( mode == MBEDTLS_RSA_PRIVATE ||
|
---|
1286 | mode == MBEDTLS_RSA_PUBLIC );
|
---|
1287 | RSA_VALIDATE_RET( output != NULL );
|
---|
1288 | RSA_VALIDATE_RET( input != NULL );
|
---|
1289 |
|
---|
1290 | switch( ctx->padding )
|
---|
1291 | {
|
---|
1292 | #if defined(MBEDTLS_PKCS1_V15)
|
---|
1293 | case MBEDTLS_RSA_PKCS_V15:
|
---|
1294 | return mbedtls_rsa_rsaes_pkcs1_v15_encrypt( ctx, f_rng, p_rng, mode, ilen,
|
---|
1295 | input, output );
|
---|
1296 | #endif
|
---|
1297 |
|
---|
1298 | #if defined(MBEDTLS_PKCS1_V21)
|
---|
1299 | case MBEDTLS_RSA_PKCS_V21:
|
---|
1300 | return mbedtls_rsa_rsaes_oaep_encrypt( ctx, f_rng, p_rng, mode, NULL, 0,
|
---|
1301 | ilen, input, output );
|
---|
1302 | #endif
|
---|
1303 |
|
---|
1304 | default:
|
---|
1305 | return( MBEDTLS_ERR_RSA_INVALID_PADDING );
|
---|
1306 | }
|
---|
1307 | }
|
---|
1308 |
|
---|
1309 | #if defined(MBEDTLS_PKCS1_V21)
|
---|
1310 | /*
|
---|
1311 | * Implementation of the PKCS#1 v2.1 RSAES-OAEP-DECRYPT function
|
---|
1312 | */
|
---|
1313 | int mbedtls_rsa_rsaes_oaep_decrypt( mbedtls_rsa_context *ctx,
|
---|
1314 | int (*f_rng)(void *, unsigned char *, size_t),
|
---|
1315 | void *p_rng,
|
---|
1316 | int mode,
|
---|
1317 | const unsigned char *label, size_t label_len,
|
---|
1318 | size_t *olen,
|
---|
1319 | const unsigned char *input,
|
---|
1320 | unsigned char *output,
|
---|
1321 | size_t output_max_len )
|
---|
1322 | {
|
---|
1323 | int ret;
|
---|
1324 | size_t ilen, i, pad_len;
|
---|
1325 | unsigned char *p, bad, pad_done;
|
---|
1326 | unsigned char buf[MBEDTLS_MPI_MAX_SIZE];
|
---|
1327 | unsigned char lhash[MBEDTLS_MD_MAX_SIZE];
|
---|
1328 | unsigned int hlen;
|
---|
1329 | const mbedtls_md_info_t *md_info;
|
---|
1330 | mbedtls_md_context_t md_ctx;
|
---|
1331 |
|
---|
1332 | RSA_VALIDATE_RET( ctx != NULL );
|
---|
1333 | RSA_VALIDATE_RET( mode == MBEDTLS_RSA_PRIVATE ||
|
---|
1334 | mode == MBEDTLS_RSA_PUBLIC );
|
---|
1335 | RSA_VALIDATE_RET( output_max_len == 0 || output != NULL );
|
---|
1336 | RSA_VALIDATE_RET( label_len == 0 || label != NULL );
|
---|
1337 | RSA_VALIDATE_RET( input != NULL );
|
---|
1338 | RSA_VALIDATE_RET( olen != NULL );
|
---|
1339 |
|
---|
1340 | /*
|
---|
1341 | * Parameters sanity checks
|
---|
1342 | */
|
---|
1343 | if( mode == MBEDTLS_RSA_PRIVATE && ctx->padding != MBEDTLS_RSA_PKCS_V21 )
|
---|
1344 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
1345 |
|
---|
1346 | ilen = ctx->len;
|
---|
1347 |
|
---|
1348 | if( ilen < 16 || ilen > sizeof( buf ) )
|
---|
1349 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
1350 |
|
---|
1351 | md_info = mbedtls_md_info_from_type( (mbedtls_md_type_t) ctx->hash_id );
|
---|
1352 | if( md_info == NULL )
|
---|
1353 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
1354 |
|
---|
1355 | hlen = mbedtls_md_get_size( md_info );
|
---|
1356 |
|
---|
1357 | // checking for integer underflow
|
---|
1358 | if( 2 * hlen + 2 > ilen )
|
---|
1359 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
1360 |
|
---|
1361 | /*
|
---|
1362 | * RSA operation
|
---|
1363 | */
|
---|
1364 | ret = ( mode == MBEDTLS_RSA_PUBLIC )
|
---|
1365 | ? mbedtls_rsa_public( ctx, input, buf )
|
---|
1366 | : mbedtls_rsa_private( ctx, f_rng, p_rng, input, buf );
|
---|
1367 |
|
---|
1368 | if( ret != 0 )
|
---|
1369 | goto cleanup;
|
---|
1370 |
|
---|
1371 | /*
|
---|
1372 | * Unmask data and generate lHash
|
---|
1373 | */
|
---|
1374 | mbedtls_md_init( &md_ctx );
|
---|
1375 | if( ( ret = mbedtls_md_setup( &md_ctx, md_info, 0 ) ) != 0 )
|
---|
1376 | {
|
---|
1377 | mbedtls_md_free( &md_ctx );
|
---|
1378 | goto cleanup;
|
---|
1379 | }
|
---|
1380 |
|
---|
1381 | /* seed: Apply seedMask to maskedSeed */
|
---|
1382 | if( ( ret = mgf_mask( buf + 1, hlen, buf + hlen + 1, ilen - hlen - 1,
|
---|
1383 | &md_ctx ) ) != 0 ||
|
---|
1384 | /* DB: Apply dbMask to maskedDB */
|
---|
1385 | ( ret = mgf_mask( buf + hlen + 1, ilen - hlen - 1, buf + 1, hlen,
|
---|
1386 | &md_ctx ) ) != 0 )
|
---|
1387 | {
|
---|
1388 | mbedtls_md_free( &md_ctx );
|
---|
1389 | goto cleanup;
|
---|
1390 | }
|
---|
1391 |
|
---|
1392 | mbedtls_md_free( &md_ctx );
|
---|
1393 |
|
---|
1394 | /* Generate lHash */
|
---|
1395 | if( ( ret = mbedtls_md( md_info, label, label_len, lhash ) ) != 0 )
|
---|
1396 | goto cleanup;
|
---|
1397 |
|
---|
1398 | /*
|
---|
1399 | * Check contents, in "constant-time"
|
---|
1400 | */
|
---|
1401 | p = buf;
|
---|
1402 | bad = 0;
|
---|
1403 |
|
---|
1404 | bad |= *p++; /* First byte must be 0 */
|
---|
1405 |
|
---|
1406 | p += hlen; /* Skip seed */
|
---|
1407 |
|
---|
1408 | /* Check lHash */
|
---|
1409 | for( i = 0; i < hlen; i++ )
|
---|
1410 | bad |= lhash[i] ^ *p++;
|
---|
1411 |
|
---|
1412 | /* Get zero-padding len, but always read till end of buffer
|
---|
1413 | * (minus one, for the 01 byte) */
|
---|
1414 | pad_len = 0;
|
---|
1415 | pad_done = 0;
|
---|
1416 | for( i = 0; i < ilen - 2 * hlen - 2; i++ )
|
---|
1417 | {
|
---|
1418 | pad_done |= p[i];
|
---|
1419 | pad_len += ((pad_done | (unsigned char)-pad_done) >> 7) ^ 1;
|
---|
1420 | }
|
---|
1421 |
|
---|
1422 | p += pad_len;
|
---|
1423 | bad |= *p++ ^ 0x01;
|
---|
1424 |
|
---|
1425 | /*
|
---|
1426 | * The only information "leaked" is whether the padding was correct or not
|
---|
1427 | * (eg, no data is copied if it was not correct). This meets the
|
---|
1428 | * recommendations in PKCS#1 v2.2: an opponent cannot distinguish between
|
---|
1429 | * the different error conditions.
|
---|
1430 | */
|
---|
1431 | if( bad != 0 )
|
---|
1432 | {
|
---|
1433 | ret = MBEDTLS_ERR_RSA_INVALID_PADDING;
|
---|
1434 | goto cleanup;
|
---|
1435 | }
|
---|
1436 |
|
---|
1437 | if( ilen - ( p - buf ) > output_max_len )
|
---|
1438 | {
|
---|
1439 | ret = MBEDTLS_ERR_RSA_OUTPUT_TOO_LARGE;
|
---|
1440 | goto cleanup;
|
---|
1441 | }
|
---|
1442 |
|
---|
1443 | *olen = ilen - (p - buf);
|
---|
1444 | memcpy( output, p, *olen );
|
---|
1445 | ret = 0;
|
---|
1446 |
|
---|
1447 | cleanup:
|
---|
1448 | mbedtls_platform_zeroize( buf, sizeof( buf ) );
|
---|
1449 | mbedtls_platform_zeroize( lhash, sizeof( lhash ) );
|
---|
1450 |
|
---|
1451 | return( ret );
|
---|
1452 | }
|
---|
1453 | #endif /* MBEDTLS_PKCS1_V21 */
|
---|
1454 |
|
---|
1455 | #if defined(MBEDTLS_PKCS1_V15)
|
---|
1456 | /** Turn zero-or-nonzero into zero-or-all-bits-one, without branches.
|
---|
1457 | *
|
---|
1458 | * \param value The value to analyze.
|
---|
1459 | * \return Zero if \p value is zero, otherwise all-bits-one.
|
---|
1460 | */
|
---|
1461 | static unsigned all_or_nothing_int( unsigned value )
|
---|
1462 | {
|
---|
1463 | /* MSVC has a warning about unary minus on unsigned, but this is
|
---|
1464 | * well-defined and precisely what we want to do here */
|
---|
1465 | #if defined(_MSC_VER)
|
---|
1466 | #pragma warning( push )
|
---|
1467 | #pragma warning( disable : 4146 )
|
---|
1468 | #endif
|
---|
1469 | return( - ( ( value | - value ) >> ( sizeof( value ) * 8 - 1 ) ) );
|
---|
1470 | #if defined(_MSC_VER)
|
---|
1471 | #pragma warning( pop )
|
---|
1472 | #endif
|
---|
1473 | }
|
---|
1474 |
|
---|
1475 | /** Check whether a size is out of bounds, without branches.
|
---|
1476 | *
|
---|
1477 | * This is equivalent to `size > max`, but is likely to be compiled to
|
---|
1478 | * to code using bitwise operation rather than a branch.
|
---|
1479 | *
|
---|
1480 | * \param size Size to check.
|
---|
1481 | * \param max Maximum desired value for \p size.
|
---|
1482 | * \return \c 0 if `size <= max`.
|
---|
1483 | * \return \c 1 if `size > max`.
|
---|
1484 | */
|
---|
1485 | static unsigned size_greater_than( size_t size, size_t max )
|
---|
1486 | {
|
---|
1487 | /* Return the sign bit (1 for negative) of (max - size). */
|
---|
1488 | return( ( max - size ) >> ( sizeof( size_t ) * 8 - 1 ) );
|
---|
1489 | }
|
---|
1490 |
|
---|
1491 | /** Choose between two integer values, without branches.
|
---|
1492 | *
|
---|
1493 | * This is equivalent to `cond ? if1 : if0`, but is likely to be compiled
|
---|
1494 | * to code using bitwise operation rather than a branch.
|
---|
1495 | *
|
---|
1496 | * \param cond Condition to test.
|
---|
1497 | * \param if1 Value to use if \p cond is nonzero.
|
---|
1498 | * \param if0 Value to use if \p cond is zero.
|
---|
1499 | * \return \c if1 if \p cond is nonzero, otherwise \c if0.
|
---|
1500 | */
|
---|
1501 | static unsigned if_int( unsigned cond, unsigned if1, unsigned if0 )
|
---|
1502 | {
|
---|
1503 | unsigned mask = all_or_nothing_int( cond );
|
---|
1504 | return( ( mask & if1 ) | (~mask & if0 ) );
|
---|
1505 | }
|
---|
1506 |
|
---|
1507 | /** Shift some data towards the left inside a buffer without leaking
|
---|
1508 | * the length of the data through side channels.
|
---|
1509 | *
|
---|
1510 | * `mem_move_to_left(start, total, offset)` is functionally equivalent to
|
---|
1511 | * ```
|
---|
1512 | * memmove(start, start + offset, total - offset);
|
---|
1513 | * memset(start + offset, 0, total - offset);
|
---|
1514 | * ```
|
---|
1515 | * but it strives to use a memory access pattern (and thus total timing)
|
---|
1516 | * that does not depend on \p offset. This timing independence comes at
|
---|
1517 | * the expense of performance.
|
---|
1518 | *
|
---|
1519 | * \param start Pointer to the start of the buffer.
|
---|
1520 | * \param total Total size of the buffer.
|
---|
1521 | * \param offset Offset from which to copy \p total - \p offset bytes.
|
---|
1522 | */
|
---|
1523 | static void mem_move_to_left( void *start,
|
---|
1524 | size_t total,
|
---|
1525 | size_t offset )
|
---|
1526 | {
|
---|
1527 | volatile unsigned char *buf = start;
|
---|
1528 | size_t i, n;
|
---|
1529 | if( total == 0 )
|
---|
1530 | return;
|
---|
1531 | for( i = 0; i < total; i++ )
|
---|
1532 | {
|
---|
1533 | unsigned no_op = size_greater_than( total - offset, i );
|
---|
1534 | /* The first `total - offset` passes are a no-op. The last
|
---|
1535 | * `offset` passes shift the data one byte to the left and
|
---|
1536 | * zero out the last byte. */
|
---|
1537 | for( n = 0; n < total - 1; n++ )
|
---|
1538 | {
|
---|
1539 | unsigned char current = buf[n];
|
---|
1540 | unsigned char next = buf[n+1];
|
---|
1541 | buf[n] = if_int( no_op, current, next );
|
---|
1542 | }
|
---|
1543 | buf[total-1] = if_int( no_op, buf[total-1], 0 );
|
---|
1544 | }
|
---|
1545 | }
|
---|
1546 |
|
---|
1547 | /*
|
---|
1548 | * Implementation of the PKCS#1 v2.1 RSAES-PKCS1-V1_5-DECRYPT function
|
---|
1549 | */
|
---|
1550 | int mbedtls_rsa_rsaes_pkcs1_v15_decrypt( mbedtls_rsa_context *ctx,
|
---|
1551 | int (*f_rng)(void *, unsigned char *, size_t),
|
---|
1552 | void *p_rng,
|
---|
1553 | int mode, size_t *olen,
|
---|
1554 | const unsigned char *input,
|
---|
1555 | unsigned char *output,
|
---|
1556 | size_t output_max_len )
|
---|
1557 | {
|
---|
1558 | int ret;
|
---|
1559 | size_t ilen, i, plaintext_max_size;
|
---|
1560 | unsigned char buf[MBEDTLS_MPI_MAX_SIZE];
|
---|
1561 | /* The following variables take sensitive values: their value must
|
---|
1562 | * not leak into the observable behavior of the function other than
|
---|
1563 | * the designated outputs (output, olen, return value). Otherwise
|
---|
1564 | * this would open the execution of the function to
|
---|
1565 | * side-channel-based variants of the Bleichenbacher padding oracle
|
---|
1566 | * attack. Potential side channels include overall timing, memory
|
---|
1567 | * access patterns (especially visible to an adversary who has access
|
---|
1568 | * to a shared memory cache), and branches (especially visible to
|
---|
1569 | * an adversary who has access to a shared code cache or to a shared
|
---|
1570 | * branch predictor). */
|
---|
1571 | size_t pad_count = 0;
|
---|
1572 | unsigned bad = 0;
|
---|
1573 | unsigned char pad_done = 0;
|
---|
1574 | size_t plaintext_size = 0;
|
---|
1575 | unsigned output_too_large;
|
---|
1576 |
|
---|
1577 | RSA_VALIDATE_RET( ctx != NULL );
|
---|
1578 | RSA_VALIDATE_RET( mode == MBEDTLS_RSA_PRIVATE ||
|
---|
1579 | mode == MBEDTLS_RSA_PUBLIC );
|
---|
1580 | RSA_VALIDATE_RET( output_max_len == 0 || output != NULL );
|
---|
1581 | RSA_VALIDATE_RET( input != NULL );
|
---|
1582 | RSA_VALIDATE_RET( olen != NULL );
|
---|
1583 |
|
---|
1584 | ilen = ctx->len;
|
---|
1585 | plaintext_max_size = ( output_max_len > ilen - 11 ?
|
---|
1586 | ilen - 11 :
|
---|
1587 | output_max_len );
|
---|
1588 |
|
---|
1589 | if( mode == MBEDTLS_RSA_PRIVATE && ctx->padding != MBEDTLS_RSA_PKCS_V15 )
|
---|
1590 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
1591 |
|
---|
1592 | if( ilen < 16 || ilen > sizeof( buf ) )
|
---|
1593 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
1594 |
|
---|
1595 | ret = ( mode == MBEDTLS_RSA_PUBLIC )
|
---|
1596 | ? mbedtls_rsa_public( ctx, input, buf )
|
---|
1597 | : mbedtls_rsa_private( ctx, f_rng, p_rng, input, buf );
|
---|
1598 |
|
---|
1599 | if( ret != 0 )
|
---|
1600 | goto cleanup;
|
---|
1601 |
|
---|
1602 | /* Check and get padding length in constant time and constant
|
---|
1603 | * memory trace. The first byte must be 0. */
|
---|
1604 | bad |= buf[0];
|
---|
1605 |
|
---|
1606 | if( mode == MBEDTLS_RSA_PRIVATE )
|
---|
1607 | {
|
---|
1608 | /* Decode EME-PKCS1-v1_5 padding: 0x00 || 0x02 || PS || 0x00
|
---|
1609 | * where PS must be at least 8 nonzero bytes. */
|
---|
1610 | bad |= buf[1] ^ MBEDTLS_RSA_CRYPT;
|
---|
1611 |
|
---|
1612 | /* Read the whole buffer. Set pad_done to nonzero if we find
|
---|
1613 | * the 0x00 byte and remember the padding length in pad_count. */
|
---|
1614 | for( i = 2; i < ilen; i++ )
|
---|
1615 | {
|
---|
1616 | pad_done |= ((buf[i] | (unsigned char)-buf[i]) >> 7) ^ 1;
|
---|
1617 | pad_count += ((pad_done | (unsigned char)-pad_done) >> 7) ^ 1;
|
---|
1618 | }
|
---|
1619 | }
|
---|
1620 | else
|
---|
1621 | {
|
---|
1622 | /* Decode EMSA-PKCS1-v1_5 padding: 0x00 || 0x01 || PS || 0x00
|
---|
1623 | * where PS must be at least 8 bytes with the value 0xFF. */
|
---|
1624 | bad |= buf[1] ^ MBEDTLS_RSA_SIGN;
|
---|
1625 |
|
---|
1626 | /* Read the whole buffer. Set pad_done to nonzero if we find
|
---|
1627 | * the 0x00 byte and remember the padding length in pad_count.
|
---|
1628 | * If there's a non-0xff byte in the padding, the padding is bad. */
|
---|
1629 | for( i = 2; i < ilen; i++ )
|
---|
1630 | {
|
---|
1631 | pad_done |= if_int( buf[i], 0, 1 );
|
---|
1632 | pad_count += if_int( pad_done, 0, 1 );
|
---|
1633 | bad |= if_int( pad_done, 0, buf[i] ^ 0xFF );
|
---|
1634 | }
|
---|
1635 | }
|
---|
1636 |
|
---|
1637 | /* If pad_done is still zero, there's no data, only unfinished padding. */
|
---|
1638 | bad |= if_int( pad_done, 0, 1 );
|
---|
1639 |
|
---|
1640 | /* There must be at least 8 bytes of padding. */
|
---|
1641 | bad |= size_greater_than( 8, pad_count );
|
---|
1642 |
|
---|
1643 | /* If the padding is valid, set plaintext_size to the number of
|
---|
1644 | * remaining bytes after stripping the padding. If the padding
|
---|
1645 | * is invalid, avoid leaking this fact through the size of the
|
---|
1646 | * output: use the maximum message size that fits in the output
|
---|
1647 | * buffer. Do it without branches to avoid leaking the padding
|
---|
1648 | * validity through timing. RSA keys are small enough that all the
|
---|
1649 | * size_t values involved fit in unsigned int. */
|
---|
1650 | plaintext_size = if_int( bad,
|
---|
1651 | (unsigned) plaintext_max_size,
|
---|
1652 | (unsigned) ( ilen - pad_count - 3 ) );
|
---|
1653 |
|
---|
1654 | /* Set output_too_large to 0 if the plaintext fits in the output
|
---|
1655 | * buffer and to 1 otherwise. */
|
---|
1656 | output_too_large = size_greater_than( plaintext_size,
|
---|
1657 | plaintext_max_size );
|
---|
1658 |
|
---|
1659 | /* Set ret without branches to avoid timing attacks. Return:
|
---|
1660 | * - INVALID_PADDING if the padding is bad (bad != 0).
|
---|
1661 | * - OUTPUT_TOO_LARGE if the padding is good but the decrypted
|
---|
1662 | * plaintext does not fit in the output buffer.
|
---|
1663 | * - 0 if the padding is correct. */
|
---|
1664 | ret = - (int) if_int( bad, - MBEDTLS_ERR_RSA_INVALID_PADDING,
|
---|
1665 | if_int( output_too_large, - MBEDTLS_ERR_RSA_OUTPUT_TOO_LARGE,
|
---|
1666 | 0 ) );
|
---|
1667 |
|
---|
1668 | /* If the padding is bad or the plaintext is too large, zero the
|
---|
1669 | * data that we're about to copy to the output buffer.
|
---|
1670 | * We need to copy the same amount of data
|
---|
1671 | * from the same buffer whether the padding is good or not to
|
---|
1672 | * avoid leaking the padding validity through overall timing or
|
---|
1673 | * through memory or cache access patterns. */
|
---|
1674 | bad = all_or_nothing_int( bad | output_too_large );
|
---|
1675 | for( i = 11; i < ilen; i++ )
|
---|
1676 | buf[i] &= ~bad;
|
---|
1677 |
|
---|
1678 | /* If the plaintext is too large, truncate it to the buffer size.
|
---|
1679 | * Copy anyway to avoid revealing the length through timing, because
|
---|
1680 | * revealing the length is as bad as revealing the padding validity
|
---|
1681 | * for a Bleichenbacher attack. */
|
---|
1682 | plaintext_size = if_int( output_too_large,
|
---|
1683 | (unsigned) plaintext_max_size,
|
---|
1684 | (unsigned) plaintext_size );
|
---|
1685 |
|
---|
1686 | /* Move the plaintext to the leftmost position where it can start in
|
---|
1687 | * the working buffer, i.e. make it start plaintext_max_size from
|
---|
1688 | * the end of the buffer. Do this with a memory access trace that
|
---|
1689 | * does not depend on the plaintext size. After this move, the
|
---|
1690 | * starting location of the plaintext is no longer sensitive
|
---|
1691 | * information. */
|
---|
1692 | mem_move_to_left( buf + ilen - plaintext_max_size,
|
---|
1693 | plaintext_max_size,
|
---|
1694 | plaintext_max_size - plaintext_size );
|
---|
1695 |
|
---|
1696 | /* Finally copy the decrypted plaintext plus trailing zeros
|
---|
1697 | * into the output buffer. */
|
---|
1698 | memcpy( output, buf + ilen - plaintext_max_size, plaintext_max_size );
|
---|
1699 |
|
---|
1700 | /* Report the amount of data we copied to the output buffer. In case
|
---|
1701 | * of errors (bad padding or output too large), the value of *olen
|
---|
1702 | * when this function returns is not specified. Making it equivalent
|
---|
1703 | * to the good case limits the risks of leaking the padding validity. */
|
---|
1704 | *olen = plaintext_size;
|
---|
1705 |
|
---|
1706 | cleanup:
|
---|
1707 | mbedtls_platform_zeroize( buf, sizeof( buf ) );
|
---|
1708 |
|
---|
1709 | return( ret );
|
---|
1710 | }
|
---|
1711 | #endif /* MBEDTLS_PKCS1_V15 */
|
---|
1712 |
|
---|
1713 | /*
|
---|
1714 | * Do an RSA operation, then remove the message padding
|
---|
1715 | */
|
---|
1716 | int mbedtls_rsa_pkcs1_decrypt( mbedtls_rsa_context *ctx,
|
---|
1717 | int (*f_rng)(void *, unsigned char *, size_t),
|
---|
1718 | void *p_rng,
|
---|
1719 | int mode, size_t *olen,
|
---|
1720 | const unsigned char *input,
|
---|
1721 | unsigned char *output,
|
---|
1722 | size_t output_max_len)
|
---|
1723 | {
|
---|
1724 | RSA_VALIDATE_RET( ctx != NULL );
|
---|
1725 | RSA_VALIDATE_RET( mode == MBEDTLS_RSA_PRIVATE ||
|
---|
1726 | mode == MBEDTLS_RSA_PUBLIC );
|
---|
1727 | RSA_VALIDATE_RET( output_max_len == 0 || output != NULL );
|
---|
1728 | RSA_VALIDATE_RET( input != NULL );
|
---|
1729 | RSA_VALIDATE_RET( olen != NULL );
|
---|
1730 |
|
---|
1731 | switch( ctx->padding )
|
---|
1732 | {
|
---|
1733 | #if defined(MBEDTLS_PKCS1_V15)
|
---|
1734 | case MBEDTLS_RSA_PKCS_V15:
|
---|
1735 | return mbedtls_rsa_rsaes_pkcs1_v15_decrypt( ctx, f_rng, p_rng, mode, olen,
|
---|
1736 | input, output, output_max_len );
|
---|
1737 | #endif
|
---|
1738 |
|
---|
1739 | #if defined(MBEDTLS_PKCS1_V21)
|
---|
1740 | case MBEDTLS_RSA_PKCS_V21:
|
---|
1741 | return mbedtls_rsa_rsaes_oaep_decrypt( ctx, f_rng, p_rng, mode, NULL, 0,
|
---|
1742 | olen, input, output,
|
---|
1743 | output_max_len );
|
---|
1744 | #endif
|
---|
1745 |
|
---|
1746 | default:
|
---|
1747 | return( MBEDTLS_ERR_RSA_INVALID_PADDING );
|
---|
1748 | }
|
---|
1749 | }
|
---|
1750 |
|
---|
1751 | #if defined(MBEDTLS_PKCS1_V21)
|
---|
1752 | /*
|
---|
1753 | * Implementation of the PKCS#1 v2.1 RSASSA-PSS-SIGN function
|
---|
1754 | */
|
---|
1755 | int mbedtls_rsa_rsassa_pss_sign( mbedtls_rsa_context *ctx,
|
---|
1756 | int (*f_rng)(void *, unsigned char *, size_t),
|
---|
1757 | void *p_rng,
|
---|
1758 | int mode,
|
---|
1759 | mbedtls_md_type_t md_alg,
|
---|
1760 | unsigned int hashlen,
|
---|
1761 | const unsigned char *hash,
|
---|
1762 | unsigned char *sig )
|
---|
1763 | {
|
---|
1764 | size_t olen;
|
---|
1765 | unsigned char *p = sig;
|
---|
1766 | unsigned char salt[MBEDTLS_MD_MAX_SIZE];
|
---|
1767 | size_t slen, min_slen, hlen, offset = 0;
|
---|
1768 | int ret;
|
---|
1769 | size_t msb;
|
---|
1770 | const mbedtls_md_info_t *md_info;
|
---|
1771 | mbedtls_md_context_t md_ctx;
|
---|
1772 | RSA_VALIDATE_RET( ctx != NULL );
|
---|
1773 | RSA_VALIDATE_RET( mode == MBEDTLS_RSA_PRIVATE ||
|
---|
1774 | mode == MBEDTLS_RSA_PUBLIC );
|
---|
1775 | RSA_VALIDATE_RET( ( md_alg == MBEDTLS_MD_NONE &&
|
---|
1776 | hashlen == 0 ) ||
|
---|
1777 | hash != NULL );
|
---|
1778 | RSA_VALIDATE_RET( sig != NULL );
|
---|
1779 |
|
---|
1780 | if( mode == MBEDTLS_RSA_PRIVATE && ctx->padding != MBEDTLS_RSA_PKCS_V21 )
|
---|
1781 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
1782 |
|
---|
1783 | if( f_rng == NULL )
|
---|
1784 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
1785 |
|
---|
1786 | olen = ctx->len;
|
---|
1787 |
|
---|
1788 | if( md_alg != MBEDTLS_MD_NONE )
|
---|
1789 | {
|
---|
1790 | /* Gather length of hash to sign */
|
---|
1791 | md_info = mbedtls_md_info_from_type( md_alg );
|
---|
1792 | if( md_info == NULL )
|
---|
1793 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
1794 |
|
---|
1795 | hashlen = mbedtls_md_get_size( md_info );
|
---|
1796 | }
|
---|
1797 |
|
---|
1798 | md_info = mbedtls_md_info_from_type( (mbedtls_md_type_t) ctx->hash_id );
|
---|
1799 | if( md_info == NULL )
|
---|
1800 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
1801 |
|
---|
1802 | hlen = mbedtls_md_get_size( md_info );
|
---|
1803 |
|
---|
1804 | /* Calculate the largest possible salt length. Normally this is the hash
|
---|
1805 | * length, which is the maximum length the salt can have. If there is not
|
---|
1806 | * enough room, use the maximum salt length that fits. The constraint is
|
---|
1807 | * that the hash length plus the salt length plus 2 bytes must be at most
|
---|
1808 | * the key length. This complies with FIPS 186-4 §5.5 (e) and RFC 8017
|
---|
1809 | * (PKCS#1 v2.2) §9.1.1 step 3. */
|
---|
1810 | min_slen = hlen - 2;
|
---|
1811 | if( olen < hlen + min_slen + 2 )
|
---|
1812 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
1813 | else if( olen >= hlen + hlen + 2 )
|
---|
1814 | slen = hlen;
|
---|
1815 | else
|
---|
1816 | slen = olen - hlen - 2;
|
---|
1817 |
|
---|
1818 | memset( sig, 0, olen );
|
---|
1819 |
|
---|
1820 | /* Generate salt of length slen */
|
---|
1821 | if( ( ret = f_rng( p_rng, salt, slen ) ) != 0 )
|
---|
1822 | return( MBEDTLS_ERR_RSA_RNG_FAILED + ret );
|
---|
1823 |
|
---|
1824 | /* Note: EMSA-PSS encoding is over the length of N - 1 bits */
|
---|
1825 | msb = mbedtls_mpi_bitlen( &ctx->N ) - 1;
|
---|
1826 | p += olen - hlen - slen - 2;
|
---|
1827 | *p++ = 0x01;
|
---|
1828 | memcpy( p, salt, slen );
|
---|
1829 | p += slen;
|
---|
1830 |
|
---|
1831 | mbedtls_md_init( &md_ctx );
|
---|
1832 | if( ( ret = mbedtls_md_setup( &md_ctx, md_info, 0 ) ) != 0 )
|
---|
1833 | goto exit;
|
---|
1834 |
|
---|
1835 | /* Generate H = Hash( M' ) */
|
---|
1836 | if( ( ret = mbedtls_md_starts( &md_ctx ) ) != 0 )
|
---|
1837 | goto exit;
|
---|
1838 | if( ( ret = mbedtls_md_update( &md_ctx, p, 8 ) ) != 0 )
|
---|
1839 | goto exit;
|
---|
1840 | if( ( ret = mbedtls_md_update( &md_ctx, hash, hashlen ) ) != 0 )
|
---|
1841 | goto exit;
|
---|
1842 | if( ( ret = mbedtls_md_update( &md_ctx, salt, slen ) ) != 0 )
|
---|
1843 | goto exit;
|
---|
1844 | if( ( ret = mbedtls_md_finish( &md_ctx, p ) ) != 0 )
|
---|
1845 | goto exit;
|
---|
1846 |
|
---|
1847 | /* Compensate for boundary condition when applying mask */
|
---|
1848 | if( msb % 8 == 0 )
|
---|
1849 | offset = 1;
|
---|
1850 |
|
---|
1851 | /* maskedDB: Apply dbMask to DB */
|
---|
1852 | if( ( ret = mgf_mask( sig + offset, olen - hlen - 1 - offset, p, hlen,
|
---|
1853 | &md_ctx ) ) != 0 )
|
---|
1854 | goto exit;
|
---|
1855 |
|
---|
1856 | msb = mbedtls_mpi_bitlen( &ctx->N ) - 1;
|
---|
1857 | sig[0] &= 0xFF >> ( olen * 8 - msb );
|
---|
1858 |
|
---|
1859 | p += hlen;
|
---|
1860 | *p++ = 0xBC;
|
---|
1861 |
|
---|
1862 | mbedtls_platform_zeroize( salt, sizeof( salt ) );
|
---|
1863 |
|
---|
1864 | exit:
|
---|
1865 | mbedtls_md_free( &md_ctx );
|
---|
1866 |
|
---|
1867 | if( ret != 0 )
|
---|
1868 | return( ret );
|
---|
1869 |
|
---|
1870 | return( ( mode == MBEDTLS_RSA_PUBLIC )
|
---|
1871 | ? mbedtls_rsa_public( ctx, sig, sig )
|
---|
1872 | : mbedtls_rsa_private( ctx, f_rng, p_rng, sig, sig ) );
|
---|
1873 | }
|
---|
1874 | #endif /* MBEDTLS_PKCS1_V21 */
|
---|
1875 |
|
---|
1876 | #if defined(MBEDTLS_PKCS1_V15)
|
---|
1877 | /*
|
---|
1878 | * Implementation of the PKCS#1 v2.1 RSASSA-PKCS1-V1_5-SIGN function
|
---|
1879 | */
|
---|
1880 |
|
---|
1881 | /* Construct a PKCS v1.5 encoding of a hashed message
|
---|
1882 | *
|
---|
1883 | * This is used both for signature generation and verification.
|
---|
1884 | *
|
---|
1885 | * Parameters:
|
---|
1886 | * - md_alg: Identifies the hash algorithm used to generate the given hash;
|
---|
1887 | * MBEDTLS_MD_NONE if raw data is signed.
|
---|
1888 | * - hashlen: Length of hash in case hashlen is MBEDTLS_MD_NONE.
|
---|
1889 | * - hash: Buffer containing the hashed message or the raw data.
|
---|
1890 | * - dst_len: Length of the encoded message.
|
---|
1891 | * - dst: Buffer to hold the encoded message.
|
---|
1892 | *
|
---|
1893 | * Assumptions:
|
---|
1894 | * - hash has size hashlen if md_alg == MBEDTLS_MD_NONE.
|
---|
1895 | * - hash has size corresponding to md_alg if md_alg != MBEDTLS_MD_NONE.
|
---|
1896 | * - dst points to a buffer of size at least dst_len.
|
---|
1897 | *
|
---|
1898 | */
|
---|
1899 | static int rsa_rsassa_pkcs1_v15_encode( mbedtls_md_type_t md_alg,
|
---|
1900 | unsigned int hashlen,
|
---|
1901 | const unsigned char *hash,
|
---|
1902 | size_t dst_len,
|
---|
1903 | unsigned char *dst )
|
---|
1904 | {
|
---|
1905 | size_t oid_size = 0;
|
---|
1906 | size_t nb_pad = dst_len;
|
---|
1907 | unsigned char *p = dst;
|
---|
1908 | const char *oid = NULL;
|
---|
1909 |
|
---|
1910 | /* Are we signing hashed or raw data? */
|
---|
1911 | if( md_alg != MBEDTLS_MD_NONE )
|
---|
1912 | {
|
---|
1913 | const mbedtls_md_info_t *md_info = mbedtls_md_info_from_type( md_alg );
|
---|
1914 | if( md_info == NULL )
|
---|
1915 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
1916 |
|
---|
1917 | if( mbedtls_oid_get_oid_by_md( md_alg, &oid, &oid_size ) != 0 )
|
---|
1918 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
1919 |
|
---|
1920 | hashlen = mbedtls_md_get_size( md_info );
|
---|
1921 |
|
---|
1922 | /* Double-check that 8 + hashlen + oid_size can be used as a
|
---|
1923 | * 1-byte ASN.1 length encoding and that there's no overflow. */
|
---|
1924 | if( 8 + hashlen + oid_size >= 0x80 ||
|
---|
1925 | 10 + hashlen < hashlen ||
|
---|
1926 | 10 + hashlen + oid_size < 10 + hashlen )
|
---|
1927 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
1928 |
|
---|
1929 | /*
|
---|
1930 | * Static bounds check:
|
---|
1931 | * - Need 10 bytes for five tag-length pairs.
|
---|
1932 | * (Insist on 1-byte length encodings to protect against variants of
|
---|
1933 | * Bleichenbacher's forgery attack against lax PKCS#1v1.5 verification)
|
---|
1934 | * - Need hashlen bytes for hash
|
---|
1935 | * - Need oid_size bytes for hash alg OID.
|
---|
1936 | */
|
---|
1937 | if( nb_pad < 10 + hashlen + oid_size )
|
---|
1938 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
1939 | nb_pad -= 10 + hashlen + oid_size;
|
---|
1940 | }
|
---|
1941 | else
|
---|
1942 | {
|
---|
1943 | if( nb_pad < hashlen )
|
---|
1944 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
1945 |
|
---|
1946 | nb_pad -= hashlen;
|
---|
1947 | }
|
---|
1948 |
|
---|
1949 | /* Need space for signature header and padding delimiter (3 bytes),
|
---|
1950 | * and 8 bytes for the minimal padding */
|
---|
1951 | if( nb_pad < 3 + 8 )
|
---|
1952 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
1953 | nb_pad -= 3;
|
---|
1954 |
|
---|
1955 | /* Now nb_pad is the amount of memory to be filled
|
---|
1956 | * with padding, and at least 8 bytes long. */
|
---|
1957 |
|
---|
1958 | /* Write signature header and padding */
|
---|
1959 | *p++ = 0;
|
---|
1960 | *p++ = MBEDTLS_RSA_SIGN;
|
---|
1961 | memset( p, 0xFF, nb_pad );
|
---|
1962 | p += nb_pad;
|
---|
1963 | *p++ = 0;
|
---|
1964 |
|
---|
1965 | /* Are we signing raw data? */
|
---|
1966 | if( md_alg == MBEDTLS_MD_NONE )
|
---|
1967 | {
|
---|
1968 | memcpy( p, hash, hashlen );
|
---|
1969 | return( 0 );
|
---|
1970 | }
|
---|
1971 |
|
---|
1972 | /* Signing hashed data, add corresponding ASN.1 structure
|
---|
1973 | *
|
---|
1974 | * DigestInfo ::= SEQUENCE {
|
---|
1975 | * digestAlgorithm DigestAlgorithmIdentifier,
|
---|
1976 | * digest Digest }
|
---|
1977 | * DigestAlgorithmIdentifier ::= AlgorithmIdentifier
|
---|
1978 | * Digest ::= OCTET STRING
|
---|
1979 | *
|
---|
1980 | * Schematic:
|
---|
1981 | * TAG-SEQ + LEN [ TAG-SEQ + LEN [ TAG-OID + LEN [ OID ]
|
---|
1982 | * TAG-NULL + LEN [ NULL ] ]
|
---|
1983 | * TAG-OCTET + LEN [ HASH ] ]
|
---|
1984 | */
|
---|
1985 | *p++ = MBEDTLS_ASN1_SEQUENCE | MBEDTLS_ASN1_CONSTRUCTED;
|
---|
1986 | *p++ = (unsigned char)( 0x08 + oid_size + hashlen );
|
---|
1987 | *p++ = MBEDTLS_ASN1_SEQUENCE | MBEDTLS_ASN1_CONSTRUCTED;
|
---|
1988 | *p++ = (unsigned char)( 0x04 + oid_size );
|
---|
1989 | *p++ = MBEDTLS_ASN1_OID;
|
---|
1990 | *p++ = (unsigned char) oid_size;
|
---|
1991 | memcpy( p, oid, oid_size );
|
---|
1992 | p += oid_size;
|
---|
1993 | *p++ = MBEDTLS_ASN1_NULL;
|
---|
1994 | *p++ = 0x00;
|
---|
1995 | *p++ = MBEDTLS_ASN1_OCTET_STRING;
|
---|
1996 | *p++ = (unsigned char) hashlen;
|
---|
1997 | memcpy( p, hash, hashlen );
|
---|
1998 | p += hashlen;
|
---|
1999 |
|
---|
2000 | /* Just a sanity-check, should be automatic
|
---|
2001 | * after the initial bounds check. */
|
---|
2002 | if( p != dst + dst_len )
|
---|
2003 | {
|
---|
2004 | mbedtls_platform_zeroize( dst, dst_len );
|
---|
2005 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
2006 | }
|
---|
2007 |
|
---|
2008 | return( 0 );
|
---|
2009 | }
|
---|
2010 |
|
---|
2011 | /*
|
---|
2012 | * Do an RSA operation to sign the message digest
|
---|
2013 | */
|
---|
2014 | int mbedtls_rsa_rsassa_pkcs1_v15_sign( mbedtls_rsa_context *ctx,
|
---|
2015 | int (*f_rng)(void *, unsigned char *, size_t),
|
---|
2016 | void *p_rng,
|
---|
2017 | int mode,
|
---|
2018 | mbedtls_md_type_t md_alg,
|
---|
2019 | unsigned int hashlen,
|
---|
2020 | const unsigned char *hash,
|
---|
2021 | unsigned char *sig )
|
---|
2022 | {
|
---|
2023 | int ret;
|
---|
2024 | unsigned char *sig_try = NULL, *verif = NULL;
|
---|
2025 |
|
---|
2026 | RSA_VALIDATE_RET( ctx != NULL );
|
---|
2027 | RSA_VALIDATE_RET( mode == MBEDTLS_RSA_PRIVATE ||
|
---|
2028 | mode == MBEDTLS_RSA_PUBLIC );
|
---|
2029 | RSA_VALIDATE_RET( ( md_alg == MBEDTLS_MD_NONE &&
|
---|
2030 | hashlen == 0 ) ||
|
---|
2031 | hash != NULL );
|
---|
2032 | RSA_VALIDATE_RET( sig != NULL );
|
---|
2033 |
|
---|
2034 | if( mode == MBEDTLS_RSA_PRIVATE && ctx->padding != MBEDTLS_RSA_PKCS_V15 )
|
---|
2035 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
2036 |
|
---|
2037 | /*
|
---|
2038 | * Prepare PKCS1-v1.5 encoding (padding and hash identifier)
|
---|
2039 | */
|
---|
2040 |
|
---|
2041 | if( ( ret = rsa_rsassa_pkcs1_v15_encode( md_alg, hashlen, hash,
|
---|
2042 | ctx->len, sig ) ) != 0 )
|
---|
2043 | return( ret );
|
---|
2044 |
|
---|
2045 | /*
|
---|
2046 | * Call respective RSA primitive
|
---|
2047 | */
|
---|
2048 |
|
---|
2049 | if( mode == MBEDTLS_RSA_PUBLIC )
|
---|
2050 | {
|
---|
2051 | /* Skip verification on a public key operation */
|
---|
2052 | return( mbedtls_rsa_public( ctx, sig, sig ) );
|
---|
2053 | }
|
---|
2054 |
|
---|
2055 | /* Private key operation
|
---|
2056 | *
|
---|
2057 | * In order to prevent Lenstra's attack, make the signature in a
|
---|
2058 | * temporary buffer and check it before returning it.
|
---|
2059 | */
|
---|
2060 |
|
---|
2061 | sig_try = mbedtls_calloc( 1, ctx->len );
|
---|
2062 | if( sig_try == NULL )
|
---|
2063 | return( MBEDTLS_ERR_MPI_ALLOC_FAILED );
|
---|
2064 |
|
---|
2065 | verif = mbedtls_calloc( 1, ctx->len );
|
---|
2066 | if( verif == NULL )
|
---|
2067 | {
|
---|
2068 | mbedtls_free( sig_try );
|
---|
2069 | return( MBEDTLS_ERR_MPI_ALLOC_FAILED );
|
---|
2070 | }
|
---|
2071 |
|
---|
2072 | MBEDTLS_MPI_CHK( mbedtls_rsa_private( ctx, f_rng, p_rng, sig, sig_try ) );
|
---|
2073 | MBEDTLS_MPI_CHK( mbedtls_rsa_public( ctx, sig_try, verif ) );
|
---|
2074 |
|
---|
2075 | if( mbedtls_safer_memcmp( verif, sig, ctx->len ) != 0 )
|
---|
2076 | {
|
---|
2077 | ret = MBEDTLS_ERR_RSA_PRIVATE_FAILED;
|
---|
2078 | goto cleanup;
|
---|
2079 | }
|
---|
2080 |
|
---|
2081 | memcpy( sig, sig_try, ctx->len );
|
---|
2082 |
|
---|
2083 | cleanup:
|
---|
2084 | mbedtls_free( sig_try );
|
---|
2085 | mbedtls_free( verif );
|
---|
2086 |
|
---|
2087 | return( ret );
|
---|
2088 | }
|
---|
2089 | #endif /* MBEDTLS_PKCS1_V15 */
|
---|
2090 |
|
---|
2091 | /*
|
---|
2092 | * Do an RSA operation to sign the message digest
|
---|
2093 | */
|
---|
2094 | int mbedtls_rsa_pkcs1_sign( mbedtls_rsa_context *ctx,
|
---|
2095 | int (*f_rng)(void *, unsigned char *, size_t),
|
---|
2096 | void *p_rng,
|
---|
2097 | int mode,
|
---|
2098 | mbedtls_md_type_t md_alg,
|
---|
2099 | unsigned int hashlen,
|
---|
2100 | const unsigned char *hash,
|
---|
2101 | unsigned char *sig )
|
---|
2102 | {
|
---|
2103 | RSA_VALIDATE_RET( ctx != NULL );
|
---|
2104 | RSA_VALIDATE_RET( mode == MBEDTLS_RSA_PRIVATE ||
|
---|
2105 | mode == MBEDTLS_RSA_PUBLIC );
|
---|
2106 | RSA_VALIDATE_RET( ( md_alg == MBEDTLS_MD_NONE &&
|
---|
2107 | hashlen == 0 ) ||
|
---|
2108 | hash != NULL );
|
---|
2109 | RSA_VALIDATE_RET( sig != NULL );
|
---|
2110 |
|
---|
2111 | switch( ctx->padding )
|
---|
2112 | {
|
---|
2113 | #if defined(MBEDTLS_PKCS1_V15)
|
---|
2114 | case MBEDTLS_RSA_PKCS_V15:
|
---|
2115 | return mbedtls_rsa_rsassa_pkcs1_v15_sign( ctx, f_rng, p_rng, mode, md_alg,
|
---|
2116 | hashlen, hash, sig );
|
---|
2117 | #endif
|
---|
2118 |
|
---|
2119 | #if defined(MBEDTLS_PKCS1_V21)
|
---|
2120 | case MBEDTLS_RSA_PKCS_V21:
|
---|
2121 | return mbedtls_rsa_rsassa_pss_sign( ctx, f_rng, p_rng, mode, md_alg,
|
---|
2122 | hashlen, hash, sig );
|
---|
2123 | #endif
|
---|
2124 |
|
---|
2125 | default:
|
---|
2126 | return( MBEDTLS_ERR_RSA_INVALID_PADDING );
|
---|
2127 | }
|
---|
2128 | }
|
---|
2129 |
|
---|
2130 | #if defined(MBEDTLS_PKCS1_V21)
|
---|
2131 | /*
|
---|
2132 | * Implementation of the PKCS#1 v2.1 RSASSA-PSS-VERIFY function
|
---|
2133 | */
|
---|
2134 | int mbedtls_rsa_rsassa_pss_verify_ext( mbedtls_rsa_context *ctx,
|
---|
2135 | int (*f_rng)(void *, unsigned char *, size_t),
|
---|
2136 | void *p_rng,
|
---|
2137 | int mode,
|
---|
2138 | mbedtls_md_type_t md_alg,
|
---|
2139 | unsigned int hashlen,
|
---|
2140 | const unsigned char *hash,
|
---|
2141 | mbedtls_md_type_t mgf1_hash_id,
|
---|
2142 | int expected_salt_len,
|
---|
2143 | const unsigned char *sig )
|
---|
2144 | {
|
---|
2145 | int ret;
|
---|
2146 | size_t siglen;
|
---|
2147 | unsigned char *p;
|
---|
2148 | unsigned char *hash_start;
|
---|
2149 | unsigned char result[MBEDTLS_MD_MAX_SIZE];
|
---|
2150 | unsigned char zeros[8];
|
---|
2151 | unsigned int hlen;
|
---|
2152 | size_t observed_salt_len, msb;
|
---|
2153 | const mbedtls_md_info_t *md_info;
|
---|
2154 | mbedtls_md_context_t md_ctx;
|
---|
2155 | unsigned char buf[MBEDTLS_MPI_MAX_SIZE];
|
---|
2156 |
|
---|
2157 | RSA_VALIDATE_RET( ctx != NULL );
|
---|
2158 | RSA_VALIDATE_RET( mode == MBEDTLS_RSA_PRIVATE ||
|
---|
2159 | mode == MBEDTLS_RSA_PUBLIC );
|
---|
2160 | RSA_VALIDATE_RET( sig != NULL );
|
---|
2161 | RSA_VALIDATE_RET( ( md_alg == MBEDTLS_MD_NONE &&
|
---|
2162 | hashlen == 0 ) ||
|
---|
2163 | hash != NULL );
|
---|
2164 |
|
---|
2165 | if( mode == MBEDTLS_RSA_PRIVATE && ctx->padding != MBEDTLS_RSA_PKCS_V21 )
|
---|
2166 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
2167 |
|
---|
2168 | siglen = ctx->len;
|
---|
2169 |
|
---|
2170 | if( siglen < 16 || siglen > sizeof( buf ) )
|
---|
2171 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
2172 |
|
---|
2173 | ret = ( mode == MBEDTLS_RSA_PUBLIC )
|
---|
2174 | ? mbedtls_rsa_public( ctx, sig, buf )
|
---|
2175 | : mbedtls_rsa_private( ctx, f_rng, p_rng, sig, buf );
|
---|
2176 |
|
---|
2177 | if( ret != 0 )
|
---|
2178 | return( ret );
|
---|
2179 |
|
---|
2180 | p = buf;
|
---|
2181 |
|
---|
2182 | if( buf[siglen - 1] != 0xBC )
|
---|
2183 | return( MBEDTLS_ERR_RSA_INVALID_PADDING );
|
---|
2184 |
|
---|
2185 | if( md_alg != MBEDTLS_MD_NONE )
|
---|
2186 | {
|
---|
2187 | /* Gather length of hash to sign */
|
---|
2188 | md_info = mbedtls_md_info_from_type( md_alg );
|
---|
2189 | if( md_info == NULL )
|
---|
2190 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
2191 |
|
---|
2192 | hashlen = mbedtls_md_get_size( md_info );
|
---|
2193 | }
|
---|
2194 |
|
---|
2195 | md_info = mbedtls_md_info_from_type( mgf1_hash_id );
|
---|
2196 | if( md_info == NULL )
|
---|
2197 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
2198 |
|
---|
2199 | hlen = mbedtls_md_get_size( md_info );
|
---|
2200 |
|
---|
2201 | memset( zeros, 0, 8 );
|
---|
2202 |
|
---|
2203 | /*
|
---|
2204 | * Note: EMSA-PSS verification is over the length of N - 1 bits
|
---|
2205 | */
|
---|
2206 | msb = mbedtls_mpi_bitlen( &ctx->N ) - 1;
|
---|
2207 |
|
---|
2208 | if( buf[0] >> ( 8 - siglen * 8 + msb ) )
|
---|
2209 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
2210 |
|
---|
2211 | /* Compensate for boundary condition when applying mask */
|
---|
2212 | if( msb % 8 == 0 )
|
---|
2213 | {
|
---|
2214 | p++;
|
---|
2215 | siglen -= 1;
|
---|
2216 | }
|
---|
2217 |
|
---|
2218 | if( siglen < hlen + 2 )
|
---|
2219 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
2220 | hash_start = p + siglen - hlen - 1;
|
---|
2221 |
|
---|
2222 | mbedtls_md_init( &md_ctx );
|
---|
2223 | if( ( ret = mbedtls_md_setup( &md_ctx, md_info, 0 ) ) != 0 )
|
---|
2224 | goto exit;
|
---|
2225 |
|
---|
2226 | ret = mgf_mask( p, siglen - hlen - 1, hash_start, hlen, &md_ctx );
|
---|
2227 | if( ret != 0 )
|
---|
2228 | goto exit;
|
---|
2229 |
|
---|
2230 | buf[0] &= 0xFF >> ( siglen * 8 - msb );
|
---|
2231 |
|
---|
2232 | while( p < hash_start - 1 && *p == 0 )
|
---|
2233 | p++;
|
---|
2234 |
|
---|
2235 | if( *p++ != 0x01 )
|
---|
2236 | {
|
---|
2237 | ret = MBEDTLS_ERR_RSA_INVALID_PADDING;
|
---|
2238 | goto exit;
|
---|
2239 | }
|
---|
2240 |
|
---|
2241 | observed_salt_len = hash_start - p;
|
---|
2242 |
|
---|
2243 | if( expected_salt_len != MBEDTLS_RSA_SALT_LEN_ANY &&
|
---|
2244 | observed_salt_len != (size_t) expected_salt_len )
|
---|
2245 | {
|
---|
2246 | ret = MBEDTLS_ERR_RSA_INVALID_PADDING;
|
---|
2247 | goto exit;
|
---|
2248 | }
|
---|
2249 |
|
---|
2250 | /*
|
---|
2251 | * Generate H = Hash( M' )
|
---|
2252 | */
|
---|
2253 | ret = mbedtls_md_starts( &md_ctx );
|
---|
2254 | if ( ret != 0 )
|
---|
2255 | goto exit;
|
---|
2256 | ret = mbedtls_md_update( &md_ctx, zeros, 8 );
|
---|
2257 | if ( ret != 0 )
|
---|
2258 | goto exit;
|
---|
2259 | ret = mbedtls_md_update( &md_ctx, hash, hashlen );
|
---|
2260 | if ( ret != 0 )
|
---|
2261 | goto exit;
|
---|
2262 | ret = mbedtls_md_update( &md_ctx, p, observed_salt_len );
|
---|
2263 | if ( ret != 0 )
|
---|
2264 | goto exit;
|
---|
2265 | ret = mbedtls_md_finish( &md_ctx, result );
|
---|
2266 | if ( ret != 0 )
|
---|
2267 | goto exit;
|
---|
2268 |
|
---|
2269 | if( memcmp( hash_start, result, hlen ) != 0 )
|
---|
2270 | {
|
---|
2271 | ret = MBEDTLS_ERR_RSA_VERIFY_FAILED;
|
---|
2272 | goto exit;
|
---|
2273 | }
|
---|
2274 |
|
---|
2275 | exit:
|
---|
2276 | mbedtls_md_free( &md_ctx );
|
---|
2277 |
|
---|
2278 | return( ret );
|
---|
2279 | }
|
---|
2280 |
|
---|
2281 | /*
|
---|
2282 | * Simplified PKCS#1 v2.1 RSASSA-PSS-VERIFY function
|
---|
2283 | */
|
---|
2284 | int mbedtls_rsa_rsassa_pss_verify( mbedtls_rsa_context *ctx,
|
---|
2285 | int (*f_rng)(void *, unsigned char *, size_t),
|
---|
2286 | void *p_rng,
|
---|
2287 | int mode,
|
---|
2288 | mbedtls_md_type_t md_alg,
|
---|
2289 | unsigned int hashlen,
|
---|
2290 | const unsigned char *hash,
|
---|
2291 | const unsigned char *sig )
|
---|
2292 | {
|
---|
2293 | mbedtls_md_type_t mgf1_hash_id;
|
---|
2294 | RSA_VALIDATE_RET( ctx != NULL );
|
---|
2295 | RSA_VALIDATE_RET( mode == MBEDTLS_RSA_PRIVATE ||
|
---|
2296 | mode == MBEDTLS_RSA_PUBLIC );
|
---|
2297 | RSA_VALIDATE_RET( sig != NULL );
|
---|
2298 | RSA_VALIDATE_RET( ( md_alg == MBEDTLS_MD_NONE &&
|
---|
2299 | hashlen == 0 ) ||
|
---|
2300 | hash != NULL );
|
---|
2301 |
|
---|
2302 | mgf1_hash_id = ( ctx->hash_id != MBEDTLS_MD_NONE )
|
---|
2303 | ? (mbedtls_md_type_t) ctx->hash_id
|
---|
2304 | : md_alg;
|
---|
2305 |
|
---|
2306 | return( mbedtls_rsa_rsassa_pss_verify_ext( ctx, f_rng, p_rng, mode,
|
---|
2307 | md_alg, hashlen, hash,
|
---|
2308 | mgf1_hash_id, MBEDTLS_RSA_SALT_LEN_ANY,
|
---|
2309 | sig ) );
|
---|
2310 |
|
---|
2311 | }
|
---|
2312 | #endif /* MBEDTLS_PKCS1_V21 */
|
---|
2313 |
|
---|
2314 | #if defined(MBEDTLS_PKCS1_V15)
|
---|
2315 | /*
|
---|
2316 | * Implementation of the PKCS#1 v2.1 RSASSA-PKCS1-v1_5-VERIFY function
|
---|
2317 | */
|
---|
2318 | int mbedtls_rsa_rsassa_pkcs1_v15_verify( mbedtls_rsa_context *ctx,
|
---|
2319 | int (*f_rng)(void *, unsigned char *, size_t),
|
---|
2320 | void *p_rng,
|
---|
2321 | int mode,
|
---|
2322 | mbedtls_md_type_t md_alg,
|
---|
2323 | unsigned int hashlen,
|
---|
2324 | const unsigned char *hash,
|
---|
2325 | const unsigned char *sig )
|
---|
2326 | {
|
---|
2327 | int ret = 0;
|
---|
2328 | size_t sig_len;
|
---|
2329 | unsigned char *encoded = NULL, *encoded_expected = NULL;
|
---|
2330 |
|
---|
2331 | RSA_VALIDATE_RET( ctx != NULL );
|
---|
2332 | RSA_VALIDATE_RET( mode == MBEDTLS_RSA_PRIVATE ||
|
---|
2333 | mode == MBEDTLS_RSA_PUBLIC );
|
---|
2334 | RSA_VALIDATE_RET( sig != NULL );
|
---|
2335 | RSA_VALIDATE_RET( ( md_alg == MBEDTLS_MD_NONE &&
|
---|
2336 | hashlen == 0 ) ||
|
---|
2337 | hash != NULL );
|
---|
2338 |
|
---|
2339 | sig_len = ctx->len;
|
---|
2340 |
|
---|
2341 | if( mode == MBEDTLS_RSA_PRIVATE && ctx->padding != MBEDTLS_RSA_PKCS_V15 )
|
---|
2342 | return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
|
---|
2343 |
|
---|
2344 | /*
|
---|
2345 | * Prepare expected PKCS1 v1.5 encoding of hash.
|
---|
2346 | */
|
---|
2347 |
|
---|
2348 | if( ( encoded = mbedtls_calloc( 1, sig_len ) ) == NULL ||
|
---|
2349 | ( encoded_expected = mbedtls_calloc( 1, sig_len ) ) == NULL )
|
---|
2350 | {
|
---|
2351 | ret = MBEDTLS_ERR_MPI_ALLOC_FAILED;
|
---|
2352 | goto cleanup;
|
---|
2353 | }
|
---|
2354 |
|
---|
2355 | if( ( ret = rsa_rsassa_pkcs1_v15_encode( md_alg, hashlen, hash, sig_len,
|
---|
2356 | encoded_expected ) ) != 0 )
|
---|
2357 | goto cleanup;
|
---|
2358 |
|
---|
2359 | /*
|
---|
2360 | * Apply RSA primitive to get what should be PKCS1 encoded hash.
|
---|
2361 | */
|
---|
2362 |
|
---|
2363 | ret = ( mode == MBEDTLS_RSA_PUBLIC )
|
---|
2364 | ? mbedtls_rsa_public( ctx, sig, encoded )
|
---|
2365 | : mbedtls_rsa_private( ctx, f_rng, p_rng, sig, encoded );
|
---|
2366 | if( ret != 0 )
|
---|
2367 | goto cleanup;
|
---|
2368 |
|
---|
2369 | /*
|
---|
2370 | * Compare
|
---|
2371 | */
|
---|
2372 |
|
---|
2373 | if( ( ret = mbedtls_safer_memcmp( encoded, encoded_expected,
|
---|
2374 | sig_len ) ) != 0 )
|
---|
2375 | {
|
---|
2376 | ret = MBEDTLS_ERR_RSA_VERIFY_FAILED;
|
---|
2377 | goto cleanup;
|
---|
2378 | }
|
---|
2379 |
|
---|
2380 | cleanup:
|
---|
2381 |
|
---|
2382 | if( encoded != NULL )
|
---|
2383 | {
|
---|
2384 | mbedtls_platform_zeroize( encoded, sig_len );
|
---|
2385 | mbedtls_free( encoded );
|
---|
2386 | }
|
---|
2387 |
|
---|
2388 | if( encoded_expected != NULL )
|
---|
2389 | {
|
---|
2390 | mbedtls_platform_zeroize( encoded_expected, sig_len );
|
---|
2391 | mbedtls_free( encoded_expected );
|
---|
2392 | }
|
---|
2393 |
|
---|
2394 | return( ret );
|
---|
2395 | }
|
---|
2396 | #endif /* MBEDTLS_PKCS1_V15 */
|
---|
2397 |
|
---|
2398 | /*
|
---|
2399 | * Do an RSA operation and check the message digest
|
---|
2400 | */
|
---|
2401 | int mbedtls_rsa_pkcs1_verify( mbedtls_rsa_context *ctx,
|
---|
2402 | int (*f_rng)(void *, unsigned char *, size_t),
|
---|
2403 | void *p_rng,
|
---|
2404 | int mode,
|
---|
2405 | mbedtls_md_type_t md_alg,
|
---|
2406 | unsigned int hashlen,
|
---|
2407 | const unsigned char *hash,
|
---|
2408 | const unsigned char *sig )
|
---|
2409 | {
|
---|
2410 | RSA_VALIDATE_RET( ctx != NULL );
|
---|
2411 | RSA_VALIDATE_RET( mode == MBEDTLS_RSA_PRIVATE ||
|
---|
2412 | mode == MBEDTLS_RSA_PUBLIC );
|
---|
2413 | RSA_VALIDATE_RET( sig != NULL );
|
---|
2414 | RSA_VALIDATE_RET( ( md_alg == MBEDTLS_MD_NONE &&
|
---|
2415 | hashlen == 0 ) ||
|
---|
2416 | hash != NULL );
|
---|
2417 |
|
---|
2418 | switch( ctx->padding )
|
---|
2419 | {
|
---|
2420 | #if defined(MBEDTLS_PKCS1_V15)
|
---|
2421 | case MBEDTLS_RSA_PKCS_V15:
|
---|
2422 | return mbedtls_rsa_rsassa_pkcs1_v15_verify( ctx, f_rng, p_rng, mode, md_alg,
|
---|
2423 | hashlen, hash, sig );
|
---|
2424 | #endif
|
---|
2425 |
|
---|
2426 | #if defined(MBEDTLS_PKCS1_V21)
|
---|
2427 | case MBEDTLS_RSA_PKCS_V21:
|
---|
2428 | return mbedtls_rsa_rsassa_pss_verify( ctx, f_rng, p_rng, mode, md_alg,
|
---|
2429 | hashlen, hash, sig );
|
---|
2430 | #endif
|
---|
2431 |
|
---|
2432 | default:
|
---|
2433 | return( MBEDTLS_ERR_RSA_INVALID_PADDING );
|
---|
2434 | }
|
---|
2435 | }
|
---|
2436 |
|
---|
2437 | /*
|
---|
2438 | * Copy the components of an RSA key
|
---|
2439 | */
|
---|
2440 | int mbedtls_rsa_copy( mbedtls_rsa_context *dst, const mbedtls_rsa_context *src )
|
---|
2441 | {
|
---|
2442 | int ret;
|
---|
2443 | RSA_VALIDATE_RET( dst != NULL );
|
---|
2444 | RSA_VALIDATE_RET( src != NULL );
|
---|
2445 |
|
---|
2446 | dst->ver = src->ver;
|
---|
2447 | dst->len = src->len;
|
---|
2448 |
|
---|
2449 | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->N, &src->N ) );
|
---|
2450 | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->E, &src->E ) );
|
---|
2451 |
|
---|
2452 | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->D, &src->D ) );
|
---|
2453 | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->P, &src->P ) );
|
---|
2454 | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->Q, &src->Q ) );
|
---|
2455 |
|
---|
2456 | #if !defined(MBEDTLS_RSA_NO_CRT)
|
---|
2457 | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->DP, &src->DP ) );
|
---|
2458 | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->DQ, &src->DQ ) );
|
---|
2459 | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->QP, &src->QP ) );
|
---|
2460 | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->RP, &src->RP ) );
|
---|
2461 | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->RQ, &src->RQ ) );
|
---|
2462 | #endif
|
---|
2463 |
|
---|
2464 | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->RN, &src->RN ) );
|
---|
2465 |
|
---|
2466 | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->Vi, &src->Vi ) );
|
---|
2467 | MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->Vf, &src->Vf ) );
|
---|
2468 |
|
---|
2469 | dst->padding = src->padding;
|
---|
2470 | dst->hash_id = src->hash_id;
|
---|
2471 |
|
---|
2472 | cleanup:
|
---|
2473 | if( ret != 0 )
|
---|
2474 | mbedtls_rsa_free( dst );
|
---|
2475 |
|
---|
2476 | return( ret );
|
---|
2477 | }
|
---|
2478 |
|
---|
2479 | /*
|
---|
2480 | * Free the components of an RSA key
|
---|
2481 | */
|
---|
2482 | void mbedtls_rsa_free( mbedtls_rsa_context *ctx )
|
---|
2483 | {
|
---|
2484 | if( ctx == NULL )
|
---|
2485 | return;
|
---|
2486 |
|
---|
2487 | mbedtls_mpi_free( &ctx->Vi );
|
---|
2488 | mbedtls_mpi_free( &ctx->Vf );
|
---|
2489 | mbedtls_mpi_free( &ctx->RN );
|
---|
2490 | mbedtls_mpi_free( &ctx->D );
|
---|
2491 | mbedtls_mpi_free( &ctx->Q );
|
---|
2492 | mbedtls_mpi_free( &ctx->P );
|
---|
2493 | mbedtls_mpi_free( &ctx->E );
|
---|
2494 | mbedtls_mpi_free( &ctx->N );
|
---|
2495 |
|
---|
2496 | #if !defined(MBEDTLS_RSA_NO_CRT)
|
---|
2497 | mbedtls_mpi_free( &ctx->RQ );
|
---|
2498 | mbedtls_mpi_free( &ctx->RP );
|
---|
2499 | mbedtls_mpi_free( &ctx->QP );
|
---|
2500 | mbedtls_mpi_free( &ctx->DQ );
|
---|
2501 | mbedtls_mpi_free( &ctx->DP );
|
---|
2502 | #endif /* MBEDTLS_RSA_NO_CRT */
|
---|
2503 |
|
---|
2504 | #if defined(MBEDTLS_THREADING_C)
|
---|
2505 | mbedtls_mutex_free( &ctx->mutex );
|
---|
2506 | #endif
|
---|
2507 | }
|
---|
2508 |
|
---|
2509 | #endif /* !MBEDTLS_RSA_ALT */
|
---|
2510 |
|
---|
2511 | #if defined(MBEDTLS_SELF_TEST)
|
---|
2512 |
|
---|
2513 | #include "mbedtls/sha1.h"
|
---|
2514 |
|
---|
2515 | /*
|
---|
2516 | * Example RSA-1024 keypair, for test purposes
|
---|
2517 | */
|
---|
2518 | #define KEY_LEN 128
|
---|
2519 |
|
---|
2520 | #define RSA_N "9292758453063D803DD603D5E777D788" \
|
---|
2521 | "8ED1D5BF35786190FA2F23EBC0848AEA" \
|
---|
2522 | "DDA92CA6C3D80B32C4D109BE0F36D6AE" \
|
---|
2523 | "7130B9CED7ACDF54CFC7555AC14EEBAB" \
|
---|
2524 | "93A89813FBF3C4F8066D2D800F7C38A8" \
|
---|
2525 | "1AE31942917403FF4946B0A83D3D3E05" \
|
---|
2526 | "EE57C6F5F5606FB5D4BC6CD34EE0801A" \
|
---|
2527 | "5E94BB77B07507233A0BC7BAC8F90F79"
|
---|
2528 |
|
---|
2529 | #define RSA_E "10001"
|
---|
2530 |
|
---|
2531 | #define RSA_D "24BF6185468786FDD303083D25E64EFC" \
|
---|
2532 | "66CA472BC44D253102F8B4A9D3BFA750" \
|
---|
2533 | "91386C0077937FE33FA3252D28855837" \
|
---|
2534 | "AE1B484A8A9A45F7EE8C0C634F99E8CD" \
|
---|
2535 | "DF79C5CE07EE72C7F123142198164234" \
|
---|
2536 | "CABB724CF78B8173B9F880FC86322407" \
|
---|
2537 | "AF1FEDFDDE2BEB674CA15F3E81A1521E" \
|
---|
2538 | "071513A1E85B5DFA031F21ECAE91A34D"
|
---|
2539 |
|
---|
2540 | #define RSA_P "C36D0EB7FCD285223CFB5AABA5BDA3D8" \
|
---|
2541 | "2C01CAD19EA484A87EA4377637E75500" \
|
---|
2542 | "FCB2005C5C7DD6EC4AC023CDA285D796" \
|
---|
2543 | "C3D9E75E1EFC42488BB4F1D13AC30A57"
|
---|
2544 |
|
---|
2545 | #define RSA_Q "C000DF51A7C77AE8D7C7370C1FF55B69" \
|
---|
2546 | "E211C2B9E5DB1ED0BF61D0D9899620F4" \
|
---|
2547 | "910E4168387E3C30AA1E00C339A79508" \
|
---|
2548 | "8452DD96A9A5EA5D9DCA68DA636032AF"
|
---|
2549 |
|
---|
2550 | #define PT_LEN 24
|
---|
2551 | #define RSA_PT "\xAA\xBB\xCC\x03\x02\x01\x00\xFF\xFF\xFF\xFF\xFF" \
|
---|
2552 | "\x11\x22\x33\x0A\x0B\x0C\xCC\xDD\xDD\xDD\xDD\xDD"
|
---|
2553 |
|
---|
2554 | #if defined(MBEDTLS_PKCS1_V15)
|
---|
2555 | static int myrand( void *rng_state, unsigned char *output, size_t len )
|
---|
2556 | {
|
---|
2557 | #if !defined(__OpenBSD__)
|
---|
2558 | size_t i;
|
---|
2559 |
|
---|
2560 | if( rng_state != NULL )
|
---|
2561 | rng_state = NULL;
|
---|
2562 |
|
---|
2563 | for( i = 0; i < len; ++i )
|
---|
2564 | output[i] = rand();
|
---|
2565 | #else
|
---|
2566 | if( rng_state != NULL )
|
---|
2567 | rng_state = NULL;
|
---|
2568 |
|
---|
2569 | arc4random_buf( output, len );
|
---|
2570 | #endif /* !OpenBSD */
|
---|
2571 |
|
---|
2572 | return( 0 );
|
---|
2573 | }
|
---|
2574 | #endif /* MBEDTLS_PKCS1_V15 */
|
---|
2575 |
|
---|
2576 | /*
|
---|
2577 | * Checkup routine
|
---|
2578 | */
|
---|
2579 | int mbedtls_rsa_self_test( int verbose )
|
---|
2580 | {
|
---|
2581 | int ret = 0;
|
---|
2582 | #if defined(MBEDTLS_PKCS1_V15)
|
---|
2583 | size_t len;
|
---|
2584 | mbedtls_rsa_context rsa;
|
---|
2585 | unsigned char rsa_plaintext[PT_LEN];
|
---|
2586 | unsigned char rsa_decrypted[PT_LEN];
|
---|
2587 | unsigned char rsa_ciphertext[KEY_LEN];
|
---|
2588 | #if defined(MBEDTLS_SHA1_C)
|
---|
2589 | unsigned char sha1sum[20];
|
---|
2590 | #endif
|
---|
2591 |
|
---|
2592 | mbedtls_mpi K;
|
---|
2593 |
|
---|
2594 | mbedtls_mpi_init( &K );
|
---|
2595 | mbedtls_rsa_init( &rsa, MBEDTLS_RSA_PKCS_V15, 0 );
|
---|
2596 |
|
---|
2597 | MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &K, 16, RSA_N ) );
|
---|
2598 | MBEDTLS_MPI_CHK( mbedtls_rsa_import( &rsa, &K, NULL, NULL, NULL, NULL ) );
|
---|
2599 | MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &K, 16, RSA_P ) );
|
---|
2600 | MBEDTLS_MPI_CHK( mbedtls_rsa_import( &rsa, NULL, &K, NULL, NULL, NULL ) );
|
---|
2601 | MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &K, 16, RSA_Q ) );
|
---|
2602 | MBEDTLS_MPI_CHK( mbedtls_rsa_import( &rsa, NULL, NULL, &K, NULL, NULL ) );
|
---|
2603 | MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &K, 16, RSA_D ) );
|
---|
2604 | MBEDTLS_MPI_CHK( mbedtls_rsa_import( &rsa, NULL, NULL, NULL, &K, NULL ) );
|
---|
2605 | MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &K, 16, RSA_E ) );
|
---|
2606 | MBEDTLS_MPI_CHK( mbedtls_rsa_import( &rsa, NULL, NULL, NULL, NULL, &K ) );
|
---|
2607 |
|
---|
2608 | MBEDTLS_MPI_CHK( mbedtls_rsa_complete( &rsa ) );
|
---|
2609 |
|
---|
2610 | if( verbose != 0 )
|
---|
2611 | mbedtls_printf( " RSA key validation: " );
|
---|
2612 |
|
---|
2613 | if( mbedtls_rsa_check_pubkey( &rsa ) != 0 ||
|
---|
2614 | mbedtls_rsa_check_privkey( &rsa ) != 0 )
|
---|
2615 | {
|
---|
2616 | if( verbose != 0 )
|
---|
2617 | mbedtls_printf( "failed\n" );
|
---|
2618 |
|
---|
2619 | ret = 1;
|
---|
2620 | goto cleanup;
|
---|
2621 | }
|
---|
2622 |
|
---|
2623 | if( verbose != 0 )
|
---|
2624 | mbedtls_printf( "passed\n PKCS#1 encryption : " );
|
---|
2625 |
|
---|
2626 | memcpy( rsa_plaintext, RSA_PT, PT_LEN );
|
---|
2627 |
|
---|
2628 | if( mbedtls_rsa_pkcs1_encrypt( &rsa, myrand, NULL, MBEDTLS_RSA_PUBLIC,
|
---|
2629 | PT_LEN, rsa_plaintext,
|
---|
2630 | rsa_ciphertext ) != 0 )
|
---|
2631 | {
|
---|
2632 | if( verbose != 0 )
|
---|
2633 | mbedtls_printf( "failed\n" );
|
---|
2634 |
|
---|
2635 | ret = 1;
|
---|
2636 | goto cleanup;
|
---|
2637 | }
|
---|
2638 |
|
---|
2639 | if( verbose != 0 )
|
---|
2640 | mbedtls_printf( "passed\n PKCS#1 decryption : " );
|
---|
2641 |
|
---|
2642 | if( mbedtls_rsa_pkcs1_decrypt( &rsa, myrand, NULL, MBEDTLS_RSA_PRIVATE,
|
---|
2643 | &len, rsa_ciphertext, rsa_decrypted,
|
---|
2644 | sizeof(rsa_decrypted) ) != 0 )
|
---|
2645 | {
|
---|
2646 | if( verbose != 0 )
|
---|
2647 | mbedtls_printf( "failed\n" );
|
---|
2648 |
|
---|
2649 | ret = 1;
|
---|
2650 | goto cleanup;
|
---|
2651 | }
|
---|
2652 |
|
---|
2653 | if( memcmp( rsa_decrypted, rsa_plaintext, len ) != 0 )
|
---|
2654 | {
|
---|
2655 | if( verbose != 0 )
|
---|
2656 | mbedtls_printf( "failed\n" );
|
---|
2657 |
|
---|
2658 | ret = 1;
|
---|
2659 | goto cleanup;
|
---|
2660 | }
|
---|
2661 |
|
---|
2662 | if( verbose != 0 )
|
---|
2663 | mbedtls_printf( "passed\n" );
|
---|
2664 |
|
---|
2665 | #if defined(MBEDTLS_SHA1_C)
|
---|
2666 | if( verbose != 0 )
|
---|
2667 | mbedtls_printf( " PKCS#1 data sign : " );
|
---|
2668 |
|
---|
2669 | if( mbedtls_sha1_ret( rsa_plaintext, PT_LEN, sha1sum ) != 0 )
|
---|
2670 | {
|
---|
2671 | if( verbose != 0 )
|
---|
2672 | mbedtls_printf( "failed\n" );
|
---|
2673 |
|
---|
2674 | return( 1 );
|
---|
2675 | }
|
---|
2676 |
|
---|
2677 | if( mbedtls_rsa_pkcs1_sign( &rsa, myrand, NULL,
|
---|
2678 | MBEDTLS_RSA_PRIVATE, MBEDTLS_MD_SHA1, 0,
|
---|
2679 | sha1sum, rsa_ciphertext ) != 0 )
|
---|
2680 | {
|
---|
2681 | if( verbose != 0 )
|
---|
2682 | mbedtls_printf( "failed\n" );
|
---|
2683 |
|
---|
2684 | ret = 1;
|
---|
2685 | goto cleanup;
|
---|
2686 | }
|
---|
2687 |
|
---|
2688 | if( verbose != 0 )
|
---|
2689 | mbedtls_printf( "passed\n PKCS#1 sig. verify: " );
|
---|
2690 |
|
---|
2691 | if( mbedtls_rsa_pkcs1_verify( &rsa, NULL, NULL,
|
---|
2692 | MBEDTLS_RSA_PUBLIC, MBEDTLS_MD_SHA1, 0,
|
---|
2693 | sha1sum, rsa_ciphertext ) != 0 )
|
---|
2694 | {
|
---|
2695 | if( verbose != 0 )
|
---|
2696 | mbedtls_printf( "failed\n" );
|
---|
2697 |
|
---|
2698 | ret = 1;
|
---|
2699 | goto cleanup;
|
---|
2700 | }
|
---|
2701 |
|
---|
2702 | if( verbose != 0 )
|
---|
2703 | mbedtls_printf( "passed\n" );
|
---|
2704 | #endif /* MBEDTLS_SHA1_C */
|
---|
2705 |
|
---|
2706 | if( verbose != 0 )
|
---|
2707 | mbedtls_printf( "\n" );
|
---|
2708 |
|
---|
2709 | cleanup:
|
---|
2710 | mbedtls_mpi_free( &K );
|
---|
2711 | mbedtls_rsa_free( &rsa );
|
---|
2712 | #else /* MBEDTLS_PKCS1_V15 */
|
---|
2713 | ((void) verbose);
|
---|
2714 | #endif /* MBEDTLS_PKCS1_V15 */
|
---|
2715 | return( ret );
|
---|
2716 | }
|
---|
2717 |
|
---|
2718 | #endif /* MBEDTLS_SELF_TEST */
|
---|
2719 |
|
---|
2720 | #endif /* MBEDTLS_RSA_C */
|
---|