Denislam Valeev / Mbed OS Nucleo_rtos_basic

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mbed-os/features/mbedtls/src/rsa.c@0:e056ac8fecf8, 2018-03-13 (annotated)

Committer:
valeyev
Date:
Tue Mar 13 07:17:50 2018 +0000
Revision:
0:e056ac8fecf8
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Who changed what in which revision?

UserRevisionLine numberNew contents of line
valeyev 0:e056ac8fecf8 1 /*
valeyev 0:e056ac8fecf8 2 * The RSA public-key cryptosystem
valeyev 0:e056ac8fecf8 3 *
valeyev 0:e056ac8fecf8 4 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
valeyev 0:e056ac8fecf8 5 * SPDX-License-Identifier: Apache-2.0
valeyev 0:e056ac8fecf8 6 *
valeyev 0:e056ac8fecf8 7 * Licensed under the Apache License, Version 2.0 (the "License"); you may
valeyev 0:e056ac8fecf8 8 * not use this file except in compliance with the License.
valeyev 0:e056ac8fecf8 9 * You may obtain a copy of the License at
valeyev 0:e056ac8fecf8 10 *
valeyev 0:e056ac8fecf8 11 * http://www.apache.org/licenses/LICENSE-2.0
valeyev 0:e056ac8fecf8 12 *
valeyev 0:e056ac8fecf8 13 * Unless required by applicable law or agreed to in writing, software
valeyev 0:e056ac8fecf8 14 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
valeyev 0:e056ac8fecf8 15 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
valeyev 0:e056ac8fecf8 16 * See the License for the specific language governing permissions and
valeyev 0:e056ac8fecf8 17 * limitations under the License.
valeyev 0:e056ac8fecf8 18 *
valeyev 0:e056ac8fecf8 19 * This file is part of mbed TLS (https://tls.mbed.org)
valeyev 0:e056ac8fecf8 20 */
valeyev 0:e056ac8fecf8 21
valeyev 0:e056ac8fecf8 22 /*
valeyev 0:e056ac8fecf8 23 * The following sources were referenced in the design of this implementation
valeyev 0:e056ac8fecf8 24 * of the RSA algorithm:
valeyev 0:e056ac8fecf8 25 *
valeyev 0:e056ac8fecf8 26 * [1] A method for obtaining digital signatures and public-key cryptosystems
valeyev 0:e056ac8fecf8 27 * R Rivest, A Shamir, and L Adleman
valeyev 0:e056ac8fecf8 28 * http://people.csail.mit.edu/rivest/pubs.html#RSA78
valeyev 0:e056ac8fecf8 29 *
valeyev 0:e056ac8fecf8 30 * [2] Handbook of Applied Cryptography - 1997, Chapter 8
valeyev 0:e056ac8fecf8 31 * Menezes, van Oorschot and Vanstone
valeyev 0:e056ac8fecf8 32 *
valeyev 0:e056ac8fecf8 33 * [3] Malware Guard Extension: Using SGX to Conceal Cache Attacks
valeyev 0:e056ac8fecf8 34 * Michael Schwarz, Samuel Weiser, Daniel Gruss, Clémentine Maurice and
valeyev 0:e056ac8fecf8 35 * Stefan Mangard
valeyev 0:e056ac8fecf8 36 * https://arxiv.org/abs/1702.08719v2
valeyev 0:e056ac8fecf8 37 *
valeyev 0:e056ac8fecf8 38 */
valeyev 0:e056ac8fecf8 39
valeyev 0:e056ac8fecf8 40 #if !defined(MBEDTLS_CONFIG_FILE)
valeyev 0:e056ac8fecf8 41 #include "mbedtls/config.h"
valeyev 0:e056ac8fecf8 42 #else
valeyev 0:e056ac8fecf8 43 #include MBEDTLS_CONFIG_FILE
valeyev 0:e056ac8fecf8 44 #endif
valeyev 0:e056ac8fecf8 45
valeyev 0:e056ac8fecf8 46 #if defined(MBEDTLS_RSA_C)
valeyev 0:e056ac8fecf8 47
valeyev 0:e056ac8fecf8 48 #include "mbedtls/rsa.h"
valeyev 0:e056ac8fecf8 49 #include "mbedtls/rsa_internal.h"
valeyev 0:e056ac8fecf8 50 #include "mbedtls/oid.h"
valeyev 0:e056ac8fecf8 51
valeyev 0:e056ac8fecf8 52 #include <string.h>
valeyev 0:e056ac8fecf8 53
valeyev 0:e056ac8fecf8 54 #if defined(MBEDTLS_PKCS1_V21)
valeyev 0:e056ac8fecf8 55 #include "mbedtls/md.h"
valeyev 0:e056ac8fecf8 56 #endif
valeyev 0:e056ac8fecf8 57
valeyev 0:e056ac8fecf8 58 #if defined(MBEDTLS_PKCS1_V15) && !defined(__OpenBSD__)
valeyev 0:e056ac8fecf8 59 #include <stdlib.h>
valeyev 0:e056ac8fecf8 60 #endif
valeyev 0:e056ac8fecf8 61
valeyev 0:e056ac8fecf8 62 #if defined(MBEDTLS_PLATFORM_C)
valeyev 0:e056ac8fecf8 63 #include "mbedtls/platform.h"
valeyev 0:e056ac8fecf8 64 #else
valeyev 0:e056ac8fecf8 65 #include <stdio.h>
valeyev 0:e056ac8fecf8 66 #define mbedtls_printf printf
valeyev 0:e056ac8fecf8 67 #define mbedtls_calloc calloc
valeyev 0:e056ac8fecf8 68 #define mbedtls_free free
valeyev 0:e056ac8fecf8 69 #endif
valeyev 0:e056ac8fecf8 70
valeyev 0:e056ac8fecf8 71 #if !defined(MBEDTLS_RSA_ALT)
valeyev 0:e056ac8fecf8 72
valeyev 0:e056ac8fecf8 73 /* Implementation that should never be optimized out by the compiler */
valeyev 0:e056ac8fecf8 74 static void mbedtls_zeroize( void *v, size_t n ) {
valeyev 0:e056ac8fecf8 75 volatile unsigned char *p = (unsigned char*)v; while( n-- ) *p++ = 0;
valeyev 0:e056ac8fecf8 76 }
valeyev 0:e056ac8fecf8 77
valeyev 0:e056ac8fecf8 78 /* constant-time buffer comparison */
valeyev 0:e056ac8fecf8 79 static inline int mbedtls_safer_memcmp( const void *a, const void *b, size_t n )
valeyev 0:e056ac8fecf8 80 {
valeyev 0:e056ac8fecf8 81 size_t i;
valeyev 0:e056ac8fecf8 82 const unsigned char *A = (const unsigned char *) a;
valeyev 0:e056ac8fecf8 83 const unsigned char *B = (const unsigned char *) b;
valeyev 0:e056ac8fecf8 84 unsigned char diff = 0;
valeyev 0:e056ac8fecf8 85
valeyev 0:e056ac8fecf8 86 for( i = 0; i < n; i++ )
valeyev 0:e056ac8fecf8 87 diff |= A[i] ^ B[i];
valeyev 0:e056ac8fecf8 88
valeyev 0:e056ac8fecf8 89 return( diff );
valeyev 0:e056ac8fecf8 90 }
valeyev 0:e056ac8fecf8 91
valeyev 0:e056ac8fecf8 92 int mbedtls_rsa_import( mbedtls_rsa_context *ctx,
valeyev 0:e056ac8fecf8 93 const mbedtls_mpi *N,
valeyev 0:e056ac8fecf8 94 const mbedtls_mpi *P, const mbedtls_mpi *Q,
valeyev 0:e056ac8fecf8 95 const mbedtls_mpi *D, const mbedtls_mpi *E )
valeyev 0:e056ac8fecf8 96 {
valeyev 0:e056ac8fecf8 97 int ret;
valeyev 0:e056ac8fecf8 98
valeyev 0:e056ac8fecf8 99 if( ( N != NULL && ( ret = mbedtls_mpi_copy( &ctx->N, N ) ) != 0 ) ||
valeyev 0:e056ac8fecf8 100 ( P != NULL && ( ret = mbedtls_mpi_copy( &ctx->P, P ) ) != 0 ) ||
valeyev 0:e056ac8fecf8 101 ( Q != NULL && ( ret = mbedtls_mpi_copy( &ctx->Q, Q ) ) != 0 ) ||
valeyev 0:e056ac8fecf8 102 ( D != NULL && ( ret = mbedtls_mpi_copy( &ctx->D, D ) ) != 0 ) ||
valeyev 0:e056ac8fecf8 103 ( E != NULL && ( ret = mbedtls_mpi_copy( &ctx->E, E ) ) != 0 ) )
valeyev 0:e056ac8fecf8 104 {
valeyev 0:e056ac8fecf8 105 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA + ret );
valeyev 0:e056ac8fecf8 106 }
valeyev 0:e056ac8fecf8 107
valeyev 0:e056ac8fecf8 108 if( N != NULL )
valeyev 0:e056ac8fecf8 109 ctx->len = mbedtls_mpi_size( &ctx->N );
valeyev 0:e056ac8fecf8 110
valeyev 0:e056ac8fecf8 111 return( 0 );
valeyev 0:e056ac8fecf8 112 }
valeyev 0:e056ac8fecf8 113
valeyev 0:e056ac8fecf8 114 int mbedtls_rsa_import_raw( mbedtls_rsa_context *ctx,
valeyev 0:e056ac8fecf8 115 unsigned char const *N, size_t N_len,
valeyev 0:e056ac8fecf8 116 unsigned char const *P, size_t P_len,
valeyev 0:e056ac8fecf8 117 unsigned char const *Q, size_t Q_len,
valeyev 0:e056ac8fecf8 118 unsigned char const *D, size_t D_len,
valeyev 0:e056ac8fecf8 119 unsigned char const *E, size_t E_len )
valeyev 0:e056ac8fecf8 120 {
valeyev 0:e056ac8fecf8 121 int ret = 0;
valeyev 0:e056ac8fecf8 122
valeyev 0:e056ac8fecf8 123 if( N != NULL )
valeyev 0:e056ac8fecf8 124 {
valeyev 0:e056ac8fecf8 125 MBEDTLS_MPI_CHK( mbedtls_mpi_read_binary( &ctx->N, N, N_len ) );
valeyev 0:e056ac8fecf8 126 ctx->len = mbedtls_mpi_size( &ctx->N );
valeyev 0:e056ac8fecf8 127 }
valeyev 0:e056ac8fecf8 128
valeyev 0:e056ac8fecf8 129 if( P != NULL )
valeyev 0:e056ac8fecf8 130 MBEDTLS_MPI_CHK( mbedtls_mpi_read_binary( &ctx->P, P, P_len ) );
valeyev 0:e056ac8fecf8 131
valeyev 0:e056ac8fecf8 132 if( Q != NULL )
valeyev 0:e056ac8fecf8 133 MBEDTLS_MPI_CHK( mbedtls_mpi_read_binary( &ctx->Q, Q, Q_len ) );
valeyev 0:e056ac8fecf8 134
valeyev 0:e056ac8fecf8 135 if( D != NULL )
valeyev 0:e056ac8fecf8 136 MBEDTLS_MPI_CHK( mbedtls_mpi_read_binary( &ctx->D, D, D_len ) );
valeyev 0:e056ac8fecf8 137
valeyev 0:e056ac8fecf8 138 if( E != NULL )
valeyev 0:e056ac8fecf8 139 MBEDTLS_MPI_CHK( mbedtls_mpi_read_binary( &ctx->E, E, E_len ) );
valeyev 0:e056ac8fecf8 140
valeyev 0:e056ac8fecf8 141 cleanup:
valeyev 0:e056ac8fecf8 142
valeyev 0:e056ac8fecf8 143 if( ret != 0 )
valeyev 0:e056ac8fecf8 144 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA + ret );
valeyev 0:e056ac8fecf8 145
valeyev 0:e056ac8fecf8 146 return( 0 );
valeyev 0:e056ac8fecf8 147 }
valeyev 0:e056ac8fecf8 148
valeyev 0:e056ac8fecf8 149 /*
valeyev 0:e056ac8fecf8 150 * Checks whether the context fields are set in such a way
valeyev 0:e056ac8fecf8 151 * that the RSA primitives will be able to execute without error.
valeyev 0:e056ac8fecf8 152 * It does *not* make guarantees for consistency of the parameters.
valeyev 0:e056ac8fecf8 153 */
valeyev 0:e056ac8fecf8 154 static int rsa_check_context( mbedtls_rsa_context const *ctx, int is_priv,
valeyev 0:e056ac8fecf8 155 int blinding_needed )
valeyev 0:e056ac8fecf8 156 {
valeyev 0:e056ac8fecf8 157 #if !defined(MBEDTLS_RSA_NO_CRT)
valeyev 0:e056ac8fecf8 158 /* blinding_needed is only used for NO_CRT to decide whether
valeyev 0:e056ac8fecf8 159 * P,Q need to be present or not. */
valeyev 0:e056ac8fecf8 160 ((void) blinding_needed);
valeyev 0:e056ac8fecf8 161 #endif
valeyev 0:e056ac8fecf8 162
valeyev 0:e056ac8fecf8 163 if( ctx->len != mbedtls_mpi_size( &ctx->N ) ||
valeyev 0:e056ac8fecf8 164 ctx->len > MBEDTLS_MPI_MAX_SIZE )
valeyev 0:e056ac8fecf8 165 {
valeyev 0:e056ac8fecf8 166 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 167 }
valeyev 0:e056ac8fecf8 168
valeyev 0:e056ac8fecf8 169 /*
valeyev 0:e056ac8fecf8 170 * 1. Modular exponentiation needs positive, odd moduli.
valeyev 0:e056ac8fecf8 171 */
valeyev 0:e056ac8fecf8 172
valeyev 0:e056ac8fecf8 173 /* Modular exponentiation wrt. N is always used for
valeyev 0:e056ac8fecf8 174 * RSA public key operations. */
valeyev 0:e056ac8fecf8 175 if( mbedtls_mpi_cmp_int( &ctx->N, 0 ) <= 0 ||
valeyev 0:e056ac8fecf8 176 mbedtls_mpi_get_bit( &ctx->N, 0 ) == 0 )
valeyev 0:e056ac8fecf8 177 {
valeyev 0:e056ac8fecf8 178 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 179 }
valeyev 0:e056ac8fecf8 180
valeyev 0:e056ac8fecf8 181 #if !defined(MBEDTLS_RSA_NO_CRT)
valeyev 0:e056ac8fecf8 182 /* Modular exponentiation for P and Q is only
valeyev 0:e056ac8fecf8 183 * used for private key operations and if CRT
valeyev 0:e056ac8fecf8 184 * is used. */
valeyev 0:e056ac8fecf8 185 if( is_priv &&
valeyev 0:e056ac8fecf8 186 ( mbedtls_mpi_cmp_int( &ctx->P, 0 ) <= 0 ||
valeyev 0:e056ac8fecf8 187 mbedtls_mpi_get_bit( &ctx->P, 0 ) == 0 ||
valeyev 0:e056ac8fecf8 188 mbedtls_mpi_cmp_int( &ctx->Q, 0 ) <= 0 ||
valeyev 0:e056ac8fecf8 189 mbedtls_mpi_get_bit( &ctx->Q, 0 ) == 0 ) )
valeyev 0:e056ac8fecf8 190 {
valeyev 0:e056ac8fecf8 191 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 192 }
valeyev 0:e056ac8fecf8 193 #endif /* !MBEDTLS_RSA_NO_CRT */
valeyev 0:e056ac8fecf8 194
valeyev 0:e056ac8fecf8 195 /*
valeyev 0:e056ac8fecf8 196 * 2. Exponents must be positive
valeyev 0:e056ac8fecf8 197 */
valeyev 0:e056ac8fecf8 198
valeyev 0:e056ac8fecf8 199 /* Always need E for public key operations */
valeyev 0:e056ac8fecf8 200 if( mbedtls_mpi_cmp_int( &ctx->E, 0 ) <= 0 )
valeyev 0:e056ac8fecf8 201 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 202
valeyev 0:e056ac8fecf8 203 #if defined(MBEDTLS_RSA_NO_CRT)
valeyev 0:e056ac8fecf8 204 /* For private key operations, use D or DP & DQ
valeyev 0:e056ac8fecf8 205 * as (unblinded) exponents. */
valeyev 0:e056ac8fecf8 206 if( is_priv && mbedtls_mpi_cmp_int( &ctx->D, 0 ) <= 0 )
valeyev 0:e056ac8fecf8 207 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 208 #else
valeyev 0:e056ac8fecf8 209 if( is_priv &&
valeyev 0:e056ac8fecf8 210 ( mbedtls_mpi_cmp_int( &ctx->DP, 0 ) <= 0 ||
valeyev 0:e056ac8fecf8 211 mbedtls_mpi_cmp_int( &ctx->DQ, 0 ) <= 0 ) )
valeyev 0:e056ac8fecf8 212 {
valeyev 0:e056ac8fecf8 213 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 214 }
valeyev 0:e056ac8fecf8 215 #endif /* MBEDTLS_RSA_NO_CRT */
valeyev 0:e056ac8fecf8 216
valeyev 0:e056ac8fecf8 217 /* Blinding shouldn't make exponents negative either,
valeyev 0:e056ac8fecf8 218 * so check that P, Q >= 1 if that hasn't yet been
valeyev 0:e056ac8fecf8 219 * done as part of 1. */
valeyev 0:e056ac8fecf8 220 #if defined(MBEDTLS_RSA_NO_CRT)
valeyev 0:e056ac8fecf8 221 if( is_priv && blinding_needed &&
valeyev 0:e056ac8fecf8 222 ( mbedtls_mpi_cmp_int( &ctx->P, 0 ) <= 0 ||
valeyev 0:e056ac8fecf8 223 mbedtls_mpi_cmp_int( &ctx->Q, 0 ) <= 0 ) )
valeyev 0:e056ac8fecf8 224 {
valeyev 0:e056ac8fecf8 225 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 226 }
valeyev 0:e056ac8fecf8 227 #endif
valeyev 0:e056ac8fecf8 228
valeyev 0:e056ac8fecf8 229 /* It wouldn't lead to an error if it wasn't satisfied,
valeyev 0:e056ac8fecf8 230 * but check for QP >= 1 nonetheless. */
valeyev 0:e056ac8fecf8 231 #if !defined(MBEDTLS_RSA_NO_CRT)
valeyev 0:e056ac8fecf8 232 if( is_priv &&
valeyev 0:e056ac8fecf8 233 mbedtls_mpi_cmp_int( &ctx->QP, 0 ) <= 0 )
valeyev 0:e056ac8fecf8 234 {
valeyev 0:e056ac8fecf8 235 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 236 }
valeyev 0:e056ac8fecf8 237 #endif
valeyev 0:e056ac8fecf8 238
valeyev 0:e056ac8fecf8 239 return( 0 );
valeyev 0:e056ac8fecf8 240 }
valeyev 0:e056ac8fecf8 241
valeyev 0:e056ac8fecf8 242 int mbedtls_rsa_complete( mbedtls_rsa_context *ctx )
valeyev 0:e056ac8fecf8 243 {
valeyev 0:e056ac8fecf8 244 int ret = 0;
valeyev 0:e056ac8fecf8 245
valeyev 0:e056ac8fecf8 246 const int have_N = ( mbedtls_mpi_cmp_int( &ctx->N, 0 ) != 0 );
valeyev 0:e056ac8fecf8 247 const int have_P = ( mbedtls_mpi_cmp_int( &ctx->P, 0 ) != 0 );
valeyev 0:e056ac8fecf8 248 const int have_Q = ( mbedtls_mpi_cmp_int( &ctx->Q, 0 ) != 0 );
valeyev 0:e056ac8fecf8 249 const int have_D = ( mbedtls_mpi_cmp_int( &ctx->D, 0 ) != 0 );
valeyev 0:e056ac8fecf8 250 const int have_E = ( mbedtls_mpi_cmp_int( &ctx->E, 0 ) != 0 );
valeyev 0:e056ac8fecf8 251
valeyev 0:e056ac8fecf8 252 /*
valeyev 0:e056ac8fecf8 253 * Check whether provided parameters are enough
valeyev 0:e056ac8fecf8 254 * to deduce all others. The following incomplete
valeyev 0:e056ac8fecf8 255 * parameter sets for private keys are supported:
valeyev 0:e056ac8fecf8 256 *
valeyev 0:e056ac8fecf8 257 * (1) P, Q missing.
valeyev 0:e056ac8fecf8 258 * (2) D and potentially N missing.
valeyev 0:e056ac8fecf8 259 *
valeyev 0:e056ac8fecf8 260 */
valeyev 0:e056ac8fecf8 261
valeyev 0:e056ac8fecf8 262 const int n_missing = have_P && have_Q && have_D && have_E;
valeyev 0:e056ac8fecf8 263 const int pq_missing = have_N && !have_P && !have_Q && have_D && have_E;
valeyev 0:e056ac8fecf8 264 const int d_missing = have_P && have_Q && !have_D && have_E;
valeyev 0:e056ac8fecf8 265 const int is_pub = have_N && !have_P && !have_Q && !have_D && have_E;
valeyev 0:e056ac8fecf8 266
valeyev 0:e056ac8fecf8 267 /* These three alternatives are mutually exclusive */
valeyev 0:e056ac8fecf8 268 const int is_priv = n_missing || pq_missing || d_missing;
valeyev 0:e056ac8fecf8 269
valeyev 0:e056ac8fecf8 270 if( !is_priv && !is_pub )
valeyev 0:e056ac8fecf8 271 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 272
valeyev 0:e056ac8fecf8 273 /*
valeyev 0:e056ac8fecf8 274 * Step 1: Deduce N if P, Q are provided.
valeyev 0:e056ac8fecf8 275 */
valeyev 0:e056ac8fecf8 276
valeyev 0:e056ac8fecf8 277 if( !have_N && have_P && have_Q )
valeyev 0:e056ac8fecf8 278 {
valeyev 0:e056ac8fecf8 279 if( ( ret = mbedtls_mpi_mul_mpi( &ctx->N, &ctx->P,
valeyev 0:e056ac8fecf8 280 &ctx->Q ) ) != 0 )
valeyev 0:e056ac8fecf8 281 {
valeyev 0:e056ac8fecf8 282 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA + ret );
valeyev 0:e056ac8fecf8 283 }
valeyev 0:e056ac8fecf8 284
valeyev 0:e056ac8fecf8 285 ctx->len = mbedtls_mpi_size( &ctx->N );
valeyev 0:e056ac8fecf8 286 }
valeyev 0:e056ac8fecf8 287
valeyev 0:e056ac8fecf8 288 /*
valeyev 0:e056ac8fecf8 289 * Step 2: Deduce and verify all remaining core parameters.
valeyev 0:e056ac8fecf8 290 */
valeyev 0:e056ac8fecf8 291
valeyev 0:e056ac8fecf8 292 if( pq_missing )
valeyev 0:e056ac8fecf8 293 {
valeyev 0:e056ac8fecf8 294 ret = mbedtls_rsa_deduce_primes( &ctx->N, &ctx->E, &ctx->D,
valeyev 0:e056ac8fecf8 295 &ctx->P, &ctx->Q );
valeyev 0:e056ac8fecf8 296 if( ret != 0 )
valeyev 0:e056ac8fecf8 297 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA + ret );
valeyev 0:e056ac8fecf8 298
valeyev 0:e056ac8fecf8 299 }
valeyev 0:e056ac8fecf8 300 else if( d_missing )
valeyev 0:e056ac8fecf8 301 {
valeyev 0:e056ac8fecf8 302 if( ( ret = mbedtls_rsa_deduce_private_exponent( &ctx->P,
valeyev 0:e056ac8fecf8 303 &ctx->Q,
valeyev 0:e056ac8fecf8 304 &ctx->E,
valeyev 0:e056ac8fecf8 305 &ctx->D ) ) != 0 )
valeyev 0:e056ac8fecf8 306 {
valeyev 0:e056ac8fecf8 307 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA + ret );
valeyev 0:e056ac8fecf8 308 }
valeyev 0:e056ac8fecf8 309 }
valeyev 0:e056ac8fecf8 310
valeyev 0:e056ac8fecf8 311 /*
valeyev 0:e056ac8fecf8 312 * Step 3: Deduce all additional parameters specific
valeyev 0:e056ac8fecf8 313 * to our current RSA implementation.
valeyev 0:e056ac8fecf8 314 */
valeyev 0:e056ac8fecf8 315
valeyev 0:e056ac8fecf8 316 #if !defined(MBEDTLS_RSA_NO_CRT)
valeyev 0:e056ac8fecf8 317 if( is_priv )
valeyev 0:e056ac8fecf8 318 {
valeyev 0:e056ac8fecf8 319 ret = mbedtls_rsa_deduce_crt( &ctx->P, &ctx->Q, &ctx->D,
valeyev 0:e056ac8fecf8 320 &ctx->DP, &ctx->DQ, &ctx->QP );
valeyev 0:e056ac8fecf8 321 if( ret != 0 )
valeyev 0:e056ac8fecf8 322 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA + ret );
valeyev 0:e056ac8fecf8 323 }
valeyev 0:e056ac8fecf8 324 #endif /* MBEDTLS_RSA_NO_CRT */
valeyev 0:e056ac8fecf8 325
valeyev 0:e056ac8fecf8 326 /*
valeyev 0:e056ac8fecf8 327 * Step 3: Basic sanity checks
valeyev 0:e056ac8fecf8 328 */
valeyev 0:e056ac8fecf8 329
valeyev 0:e056ac8fecf8 330 return( rsa_check_context( ctx, is_priv, 1 ) );
valeyev 0:e056ac8fecf8 331 }
valeyev 0:e056ac8fecf8 332
valeyev 0:e056ac8fecf8 333 int mbedtls_rsa_export_raw( const mbedtls_rsa_context *ctx,
valeyev 0:e056ac8fecf8 334 unsigned char *N, size_t N_len,
valeyev 0:e056ac8fecf8 335 unsigned char *P, size_t P_len,
valeyev 0:e056ac8fecf8 336 unsigned char *Q, size_t Q_len,
valeyev 0:e056ac8fecf8 337 unsigned char *D, size_t D_len,
valeyev 0:e056ac8fecf8 338 unsigned char *E, size_t E_len )
valeyev 0:e056ac8fecf8 339 {
valeyev 0:e056ac8fecf8 340 int ret = 0;
valeyev 0:e056ac8fecf8 341
valeyev 0:e056ac8fecf8 342 /* Check if key is private or public */
valeyev 0:e056ac8fecf8 343 const int is_priv =
valeyev 0:e056ac8fecf8 344 mbedtls_mpi_cmp_int( &ctx->N, 0 ) != 0 &&
valeyev 0:e056ac8fecf8 345 mbedtls_mpi_cmp_int( &ctx->P, 0 ) != 0 &&
valeyev 0:e056ac8fecf8 346 mbedtls_mpi_cmp_int( &ctx->Q, 0 ) != 0 &&
valeyev 0:e056ac8fecf8 347 mbedtls_mpi_cmp_int( &ctx->D, 0 ) != 0 &&
valeyev 0:e056ac8fecf8 348 mbedtls_mpi_cmp_int( &ctx->E, 0 ) != 0;
valeyev 0:e056ac8fecf8 349
valeyev 0:e056ac8fecf8 350 if( !is_priv )
valeyev 0:e056ac8fecf8 351 {
valeyev 0:e056ac8fecf8 352 /* If we're trying to export private parameters for a public key,
valeyev 0:e056ac8fecf8 353 * something must be wrong. */
valeyev 0:e056ac8fecf8 354 if( P != NULL || Q != NULL || D != NULL )
valeyev 0:e056ac8fecf8 355 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 356
valeyev 0:e056ac8fecf8 357 }
valeyev 0:e056ac8fecf8 358
valeyev 0:e056ac8fecf8 359 if( N != NULL )
valeyev 0:e056ac8fecf8 360 MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary( &ctx->N, N, N_len ) );
valeyev 0:e056ac8fecf8 361
valeyev 0:e056ac8fecf8 362 if( P != NULL )
valeyev 0:e056ac8fecf8 363 MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary( &ctx->P, P, P_len ) );
valeyev 0:e056ac8fecf8 364
valeyev 0:e056ac8fecf8 365 if( Q != NULL )
valeyev 0:e056ac8fecf8 366 MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary( &ctx->Q, Q, Q_len ) );
valeyev 0:e056ac8fecf8 367
valeyev 0:e056ac8fecf8 368 if( D != NULL )
valeyev 0:e056ac8fecf8 369 MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary( &ctx->D, D, D_len ) );
valeyev 0:e056ac8fecf8 370
valeyev 0:e056ac8fecf8 371 if( E != NULL )
valeyev 0:e056ac8fecf8 372 MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary( &ctx->E, E, E_len ) );
valeyev 0:e056ac8fecf8 373
valeyev 0:e056ac8fecf8 374 cleanup:
valeyev 0:e056ac8fecf8 375
valeyev 0:e056ac8fecf8 376 return( ret );
valeyev 0:e056ac8fecf8 377 }
valeyev 0:e056ac8fecf8 378
valeyev 0:e056ac8fecf8 379 int mbedtls_rsa_export( const mbedtls_rsa_context *ctx,
valeyev 0:e056ac8fecf8 380 mbedtls_mpi *N, mbedtls_mpi *P, mbedtls_mpi *Q,
valeyev 0:e056ac8fecf8 381 mbedtls_mpi *D, mbedtls_mpi *E )
valeyev 0:e056ac8fecf8 382 {
valeyev 0:e056ac8fecf8 383 int ret;
valeyev 0:e056ac8fecf8 384
valeyev 0:e056ac8fecf8 385 /* Check if key is private or public */
valeyev 0:e056ac8fecf8 386 int is_priv =
valeyev 0:e056ac8fecf8 387 mbedtls_mpi_cmp_int( &ctx->N, 0 ) != 0 &&
valeyev 0:e056ac8fecf8 388 mbedtls_mpi_cmp_int( &ctx->P, 0 ) != 0 &&
valeyev 0:e056ac8fecf8 389 mbedtls_mpi_cmp_int( &ctx->Q, 0 ) != 0 &&
valeyev 0:e056ac8fecf8 390 mbedtls_mpi_cmp_int( &ctx->D, 0 ) != 0 &&
valeyev 0:e056ac8fecf8 391 mbedtls_mpi_cmp_int( &ctx->E, 0 ) != 0;
valeyev 0:e056ac8fecf8 392
valeyev 0:e056ac8fecf8 393 if( !is_priv )
valeyev 0:e056ac8fecf8 394 {
valeyev 0:e056ac8fecf8 395 /* If we're trying to export private parameters for a public key,
valeyev 0:e056ac8fecf8 396 * something must be wrong. */
valeyev 0:e056ac8fecf8 397 if( P != NULL || Q != NULL || D != NULL )
valeyev 0:e056ac8fecf8 398 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 399
valeyev 0:e056ac8fecf8 400 }
valeyev 0:e056ac8fecf8 401
valeyev 0:e056ac8fecf8 402 /* Export all requested core parameters. */
valeyev 0:e056ac8fecf8 403
valeyev 0:e056ac8fecf8 404 if( ( N != NULL && ( ret = mbedtls_mpi_copy( N, &ctx->N ) ) != 0 ) ||
valeyev 0:e056ac8fecf8 405 ( P != NULL && ( ret = mbedtls_mpi_copy( P, &ctx->P ) ) != 0 ) ||
valeyev 0:e056ac8fecf8 406 ( Q != NULL && ( ret = mbedtls_mpi_copy( Q, &ctx->Q ) ) != 0 ) ||
valeyev 0:e056ac8fecf8 407 ( D != NULL && ( ret = mbedtls_mpi_copy( D, &ctx->D ) ) != 0 ) ||
valeyev 0:e056ac8fecf8 408 ( E != NULL && ( ret = mbedtls_mpi_copy( E, &ctx->E ) ) != 0 ) )
valeyev 0:e056ac8fecf8 409 {
valeyev 0:e056ac8fecf8 410 return( ret );
valeyev 0:e056ac8fecf8 411 }
valeyev 0:e056ac8fecf8 412
valeyev 0:e056ac8fecf8 413 return( 0 );
valeyev 0:e056ac8fecf8 414 }
valeyev 0:e056ac8fecf8 415
valeyev 0:e056ac8fecf8 416 /*
valeyev 0:e056ac8fecf8 417 * Export CRT parameters
valeyev 0:e056ac8fecf8 418 * This must also be implemented if CRT is not used, for being able to
valeyev 0:e056ac8fecf8 419 * write DER encoded RSA keys. The helper function mbedtls_rsa_deduce_crt
valeyev 0:e056ac8fecf8 420 * can be used in this case.
valeyev 0:e056ac8fecf8 421 */
valeyev 0:e056ac8fecf8 422 int mbedtls_rsa_export_crt( const mbedtls_rsa_context *ctx,
valeyev 0:e056ac8fecf8 423 mbedtls_mpi *DP, mbedtls_mpi *DQ, mbedtls_mpi *QP )
valeyev 0:e056ac8fecf8 424 {
valeyev 0:e056ac8fecf8 425 int ret;
valeyev 0:e056ac8fecf8 426
valeyev 0:e056ac8fecf8 427 /* Check if key is private or public */
valeyev 0:e056ac8fecf8 428 int is_priv =
valeyev 0:e056ac8fecf8 429 mbedtls_mpi_cmp_int( &ctx->N, 0 ) != 0 &&
valeyev 0:e056ac8fecf8 430 mbedtls_mpi_cmp_int( &ctx->P, 0 ) != 0 &&
valeyev 0:e056ac8fecf8 431 mbedtls_mpi_cmp_int( &ctx->Q, 0 ) != 0 &&
valeyev 0:e056ac8fecf8 432 mbedtls_mpi_cmp_int( &ctx->D, 0 ) != 0 &&
valeyev 0:e056ac8fecf8 433 mbedtls_mpi_cmp_int( &ctx->E, 0 ) != 0;
valeyev 0:e056ac8fecf8 434
valeyev 0:e056ac8fecf8 435 if( !is_priv )
valeyev 0:e056ac8fecf8 436 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 437
valeyev 0:e056ac8fecf8 438 #if !defined(MBEDTLS_RSA_NO_CRT)
valeyev 0:e056ac8fecf8 439 /* Export all requested blinding parameters. */
valeyev 0:e056ac8fecf8 440 if( ( DP != NULL && ( ret = mbedtls_mpi_copy( DP, &ctx->DP ) ) != 0 ) ||
valeyev 0:e056ac8fecf8 441 ( DQ != NULL && ( ret = mbedtls_mpi_copy( DQ, &ctx->DQ ) ) != 0 ) ||
valeyev 0:e056ac8fecf8 442 ( QP != NULL && ( ret = mbedtls_mpi_copy( QP, &ctx->QP ) ) != 0 ) )
valeyev 0:e056ac8fecf8 443 {
valeyev 0:e056ac8fecf8 444 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA + ret );
valeyev 0:e056ac8fecf8 445 }
valeyev 0:e056ac8fecf8 446 #else
valeyev 0:e056ac8fecf8 447 if( ( ret = mbedtls_rsa_deduce_crt( &ctx->P, &ctx->Q, &ctx->D,
valeyev 0:e056ac8fecf8 448 DP, DQ, QP ) ) != 0 )
valeyev 0:e056ac8fecf8 449 {
valeyev 0:e056ac8fecf8 450 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA + ret );
valeyev 0:e056ac8fecf8 451 }
valeyev 0:e056ac8fecf8 452 #endif
valeyev 0:e056ac8fecf8 453
valeyev 0:e056ac8fecf8 454 return( 0 );
valeyev 0:e056ac8fecf8 455 }
valeyev 0:e056ac8fecf8 456
valeyev 0:e056ac8fecf8 457 /*
valeyev 0:e056ac8fecf8 458 * Initialize an RSA context
valeyev 0:e056ac8fecf8 459 */
valeyev 0:e056ac8fecf8 460 void mbedtls_rsa_init( mbedtls_rsa_context *ctx,
valeyev 0:e056ac8fecf8 461 int padding,
valeyev 0:e056ac8fecf8 462 int hash_id )
valeyev 0:e056ac8fecf8 463 {
valeyev 0:e056ac8fecf8 464 memset( ctx, 0, sizeof( mbedtls_rsa_context ) );
valeyev 0:e056ac8fecf8 465
valeyev 0:e056ac8fecf8 466 mbedtls_rsa_set_padding( ctx, padding, hash_id );
valeyev 0:e056ac8fecf8 467
valeyev 0:e056ac8fecf8 468 #if defined(MBEDTLS_THREADING_C)
valeyev 0:e056ac8fecf8 469 mbedtls_mutex_init( &ctx->mutex );
valeyev 0:e056ac8fecf8 470 #endif
valeyev 0:e056ac8fecf8 471 }
valeyev 0:e056ac8fecf8 472
valeyev 0:e056ac8fecf8 473 /*
valeyev 0:e056ac8fecf8 474 * Set padding for an existing RSA context
valeyev 0:e056ac8fecf8 475 */
valeyev 0:e056ac8fecf8 476 void mbedtls_rsa_set_padding( mbedtls_rsa_context *ctx, int padding, int hash_id )
valeyev 0:e056ac8fecf8 477 {
valeyev 0:e056ac8fecf8 478 ctx->padding = padding;
valeyev 0:e056ac8fecf8 479 ctx->hash_id = hash_id;
valeyev 0:e056ac8fecf8 480 }
valeyev 0:e056ac8fecf8 481
valeyev 0:e056ac8fecf8 482 /*
valeyev 0:e056ac8fecf8 483 * Get length in bytes of RSA modulus
valeyev 0:e056ac8fecf8 484 */
valeyev 0:e056ac8fecf8 485
valeyev 0:e056ac8fecf8 486 size_t mbedtls_rsa_get_len( const mbedtls_rsa_context *ctx )
valeyev 0:e056ac8fecf8 487 {
valeyev 0:e056ac8fecf8 488 return( ctx->len );
valeyev 0:e056ac8fecf8 489 }
valeyev 0:e056ac8fecf8 490
valeyev 0:e056ac8fecf8 491
valeyev 0:e056ac8fecf8 492 #if defined(MBEDTLS_GENPRIME)
valeyev 0:e056ac8fecf8 493
valeyev 0:e056ac8fecf8 494 /*
valeyev 0:e056ac8fecf8 495 * Generate an RSA keypair
valeyev 0:e056ac8fecf8 496 */
valeyev 0:e056ac8fecf8 497 int mbedtls_rsa_gen_key( mbedtls_rsa_context *ctx,
valeyev 0:e056ac8fecf8 498 int (*f_rng)(void *, unsigned char *, size_t),
valeyev 0:e056ac8fecf8 499 void *p_rng,
valeyev 0:e056ac8fecf8 500 unsigned int nbits, int exponent )
valeyev 0:e056ac8fecf8 501 {
valeyev 0:e056ac8fecf8 502 int ret;
valeyev 0:e056ac8fecf8 503 mbedtls_mpi H, G;
valeyev 0:e056ac8fecf8 504
valeyev 0:e056ac8fecf8 505 if( f_rng == NULL || nbits < 128 || exponent < 3 )
valeyev 0:e056ac8fecf8 506 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 507
valeyev 0:e056ac8fecf8 508 if( nbits % 2 )
valeyev 0:e056ac8fecf8 509 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 510
valeyev 0:e056ac8fecf8 511 mbedtls_mpi_init( &H );
valeyev 0:e056ac8fecf8 512 mbedtls_mpi_init( &G );
valeyev 0:e056ac8fecf8 513
valeyev 0:e056ac8fecf8 514 /*
valeyev 0:e056ac8fecf8 515 * find primes P and Q with Q < P so that:
valeyev 0:e056ac8fecf8 516 * GCD( E, (P-1)*(Q-1) ) == 1
valeyev 0:e056ac8fecf8 517 */
valeyev 0:e056ac8fecf8 518 MBEDTLS_MPI_CHK( mbedtls_mpi_lset( &ctx->E, exponent ) );
valeyev 0:e056ac8fecf8 519
valeyev 0:e056ac8fecf8 520 do
valeyev 0:e056ac8fecf8 521 {
valeyev 0:e056ac8fecf8 522 MBEDTLS_MPI_CHK( mbedtls_mpi_gen_prime( &ctx->P, nbits >> 1, 0,
valeyev 0:e056ac8fecf8 523 f_rng, p_rng ) );
valeyev 0:e056ac8fecf8 524
valeyev 0:e056ac8fecf8 525 MBEDTLS_MPI_CHK( mbedtls_mpi_gen_prime( &ctx->Q, nbits >> 1, 0,
valeyev 0:e056ac8fecf8 526 f_rng, p_rng ) );
valeyev 0:e056ac8fecf8 527
valeyev 0:e056ac8fecf8 528 if( mbedtls_mpi_cmp_mpi( &ctx->P, &ctx->Q ) == 0 )
valeyev 0:e056ac8fecf8 529 continue;
valeyev 0:e056ac8fecf8 530
valeyev 0:e056ac8fecf8 531 MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &ctx->N, &ctx->P, &ctx->Q ) );
valeyev 0:e056ac8fecf8 532 if( mbedtls_mpi_bitlen( &ctx->N ) != nbits )
valeyev 0:e056ac8fecf8 533 continue;
valeyev 0:e056ac8fecf8 534
valeyev 0:e056ac8fecf8 535 if( mbedtls_mpi_cmp_mpi( &ctx->P, &ctx->Q ) < 0 )
valeyev 0:e056ac8fecf8 536 mbedtls_mpi_swap( &ctx->P, &ctx->Q );
valeyev 0:e056ac8fecf8 537
valeyev 0:e056ac8fecf8 538 /* Temporarily replace P,Q by P-1, Q-1 */
valeyev 0:e056ac8fecf8 539 MBEDTLS_MPI_CHK( mbedtls_mpi_sub_int( &ctx->P, &ctx->P, 1 ) );
valeyev 0:e056ac8fecf8 540 MBEDTLS_MPI_CHK( mbedtls_mpi_sub_int( &ctx->Q, &ctx->Q, 1 ) );
valeyev 0:e056ac8fecf8 541 MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &H, &ctx->P, &ctx->Q ) );
valeyev 0:e056ac8fecf8 542 MBEDTLS_MPI_CHK( mbedtls_mpi_gcd( &G, &ctx->E, &H ) );
valeyev 0:e056ac8fecf8 543 }
valeyev 0:e056ac8fecf8 544 while( mbedtls_mpi_cmp_int( &G, 1 ) != 0 );
valeyev 0:e056ac8fecf8 545
valeyev 0:e056ac8fecf8 546 /* Restore P,Q */
valeyev 0:e056ac8fecf8 547 MBEDTLS_MPI_CHK( mbedtls_mpi_add_int( &ctx->P, &ctx->P, 1 ) );
valeyev 0:e056ac8fecf8 548 MBEDTLS_MPI_CHK( mbedtls_mpi_add_int( &ctx->Q, &ctx->Q, 1 ) );
valeyev 0:e056ac8fecf8 549
valeyev 0:e056ac8fecf8 550 ctx->len = mbedtls_mpi_size( &ctx->N );
valeyev 0:e056ac8fecf8 551
valeyev 0:e056ac8fecf8 552 /*
valeyev 0:e056ac8fecf8 553 * D = E^-1 mod ((P-1)*(Q-1))
valeyev 0:e056ac8fecf8 554 * DP = D mod (P - 1)
valeyev 0:e056ac8fecf8 555 * DQ = D mod (Q - 1)
valeyev 0:e056ac8fecf8 556 * QP = Q^-1 mod P
valeyev 0:e056ac8fecf8 557 */
valeyev 0:e056ac8fecf8 558
valeyev 0:e056ac8fecf8 559 MBEDTLS_MPI_CHK( mbedtls_mpi_inv_mod( &ctx->D, &ctx->E, &H ) );
valeyev 0:e056ac8fecf8 560
valeyev 0:e056ac8fecf8 561 #if !defined(MBEDTLS_RSA_NO_CRT)
valeyev 0:e056ac8fecf8 562 MBEDTLS_MPI_CHK( mbedtls_rsa_deduce_crt( &ctx->P, &ctx->Q, &ctx->D,
valeyev 0:e056ac8fecf8 563 &ctx->DP, &ctx->DQ, &ctx->QP ) );
valeyev 0:e056ac8fecf8 564 #endif /* MBEDTLS_RSA_NO_CRT */
valeyev 0:e056ac8fecf8 565
valeyev 0:e056ac8fecf8 566 /* Double-check */
valeyev 0:e056ac8fecf8 567 MBEDTLS_MPI_CHK( mbedtls_rsa_check_privkey( ctx ) );
valeyev 0:e056ac8fecf8 568
valeyev 0:e056ac8fecf8 569 cleanup:
valeyev 0:e056ac8fecf8 570
valeyev 0:e056ac8fecf8 571 mbedtls_mpi_free( &H );
valeyev 0:e056ac8fecf8 572 mbedtls_mpi_free( &G );
valeyev 0:e056ac8fecf8 573
valeyev 0:e056ac8fecf8 574 if( ret != 0 )
valeyev 0:e056ac8fecf8 575 {
valeyev 0:e056ac8fecf8 576 mbedtls_rsa_free( ctx );
valeyev 0:e056ac8fecf8 577 return( MBEDTLS_ERR_RSA_KEY_GEN_FAILED + ret );
valeyev 0:e056ac8fecf8 578 }
valeyev 0:e056ac8fecf8 579
valeyev 0:e056ac8fecf8 580 return( 0 );
valeyev 0:e056ac8fecf8 581 }
valeyev 0:e056ac8fecf8 582
valeyev 0:e056ac8fecf8 583 #endif /* MBEDTLS_GENPRIME */
valeyev 0:e056ac8fecf8 584
valeyev 0:e056ac8fecf8 585 /*
valeyev 0:e056ac8fecf8 586 * Check a public RSA key
valeyev 0:e056ac8fecf8 587 */
valeyev 0:e056ac8fecf8 588 int mbedtls_rsa_check_pubkey( const mbedtls_rsa_context *ctx )
valeyev 0:e056ac8fecf8 589 {
valeyev 0:e056ac8fecf8 590 if( rsa_check_context( ctx, 0 /* public */, 0 /* no blinding */ ) != 0 )
valeyev 0:e056ac8fecf8 591 return( MBEDTLS_ERR_RSA_KEY_CHECK_FAILED );
valeyev 0:e056ac8fecf8 592
valeyev 0:e056ac8fecf8 593 if( mbedtls_mpi_bitlen( &ctx->N ) < 128 )
valeyev 0:e056ac8fecf8 594 {
valeyev 0:e056ac8fecf8 595 return( MBEDTLS_ERR_RSA_KEY_CHECK_FAILED );
valeyev 0:e056ac8fecf8 596 }
valeyev 0:e056ac8fecf8 597
valeyev 0:e056ac8fecf8 598 if( mbedtls_mpi_get_bit( &ctx->E, 0 ) == 0 ||
valeyev 0:e056ac8fecf8 599 mbedtls_mpi_bitlen( &ctx->E ) < 2 ||
valeyev 0:e056ac8fecf8 600 mbedtls_mpi_cmp_mpi( &ctx->E, &ctx->N ) >= 0 )
valeyev 0:e056ac8fecf8 601 {
valeyev 0:e056ac8fecf8 602 return( MBEDTLS_ERR_RSA_KEY_CHECK_FAILED );
valeyev 0:e056ac8fecf8 603 }
valeyev 0:e056ac8fecf8 604
valeyev 0:e056ac8fecf8 605 return( 0 );
valeyev 0:e056ac8fecf8 606 }
valeyev 0:e056ac8fecf8 607
valeyev 0:e056ac8fecf8 608 /*
valeyev 0:e056ac8fecf8 609 * Check for the consistency of all fields in an RSA private key context
valeyev 0:e056ac8fecf8 610 */
valeyev 0:e056ac8fecf8 611 int mbedtls_rsa_check_privkey( const mbedtls_rsa_context *ctx )
valeyev 0:e056ac8fecf8 612 {
valeyev 0:e056ac8fecf8 613 if( mbedtls_rsa_check_pubkey( ctx ) != 0 ||
valeyev 0:e056ac8fecf8 614 rsa_check_context( ctx, 1 /* private */, 1 /* blinding */ ) != 0 )
valeyev 0:e056ac8fecf8 615 {
valeyev 0:e056ac8fecf8 616 return( MBEDTLS_ERR_RSA_KEY_CHECK_FAILED );
valeyev 0:e056ac8fecf8 617 }
valeyev 0:e056ac8fecf8 618
valeyev 0:e056ac8fecf8 619 if( mbedtls_rsa_validate_params( &ctx->N, &ctx->P, &ctx->Q,
valeyev 0:e056ac8fecf8 620 &ctx->D, &ctx->E, NULL, NULL ) != 0 )
valeyev 0:e056ac8fecf8 621 {
valeyev 0:e056ac8fecf8 622 return( MBEDTLS_ERR_RSA_KEY_CHECK_FAILED );
valeyev 0:e056ac8fecf8 623 }
valeyev 0:e056ac8fecf8 624
valeyev 0:e056ac8fecf8 625 #if !defined(MBEDTLS_RSA_NO_CRT)
valeyev 0:e056ac8fecf8 626 else if( mbedtls_rsa_validate_crt( &ctx->P, &ctx->Q, &ctx->D,
valeyev 0:e056ac8fecf8 627 &ctx->DP, &ctx->DQ, &ctx->QP ) != 0 )
valeyev 0:e056ac8fecf8 628 {
valeyev 0:e056ac8fecf8 629 return( MBEDTLS_ERR_RSA_KEY_CHECK_FAILED );
valeyev 0:e056ac8fecf8 630 }
valeyev 0:e056ac8fecf8 631 #endif
valeyev 0:e056ac8fecf8 632
valeyev 0:e056ac8fecf8 633 return( 0 );
valeyev 0:e056ac8fecf8 634 }
valeyev 0:e056ac8fecf8 635
valeyev 0:e056ac8fecf8 636 /*
valeyev 0:e056ac8fecf8 637 * Check if contexts holding a public and private key match
valeyev 0:e056ac8fecf8 638 */
valeyev 0:e056ac8fecf8 639 int mbedtls_rsa_check_pub_priv( const mbedtls_rsa_context *pub,
valeyev 0:e056ac8fecf8 640 const mbedtls_rsa_context *prv )
valeyev 0:e056ac8fecf8 641 {
valeyev 0:e056ac8fecf8 642 if( mbedtls_rsa_check_pubkey( pub ) != 0 ||
valeyev 0:e056ac8fecf8 643 mbedtls_rsa_check_privkey( prv ) != 0 )
valeyev 0:e056ac8fecf8 644 {
valeyev 0:e056ac8fecf8 645 return( MBEDTLS_ERR_RSA_KEY_CHECK_FAILED );
valeyev 0:e056ac8fecf8 646 }
valeyev 0:e056ac8fecf8 647
valeyev 0:e056ac8fecf8 648 if( mbedtls_mpi_cmp_mpi( &pub->N, &prv->N ) != 0 ||
valeyev 0:e056ac8fecf8 649 mbedtls_mpi_cmp_mpi( &pub->E, &prv->E ) != 0 )
valeyev 0:e056ac8fecf8 650 {
valeyev 0:e056ac8fecf8 651 return( MBEDTLS_ERR_RSA_KEY_CHECK_FAILED );
valeyev 0:e056ac8fecf8 652 }
valeyev 0:e056ac8fecf8 653
valeyev 0:e056ac8fecf8 654 return( 0 );
valeyev 0:e056ac8fecf8 655 }
valeyev 0:e056ac8fecf8 656
valeyev 0:e056ac8fecf8 657 /*
valeyev 0:e056ac8fecf8 658 * Do an RSA public key operation
valeyev 0:e056ac8fecf8 659 */
valeyev 0:e056ac8fecf8 660 int mbedtls_rsa_public( mbedtls_rsa_context *ctx,
valeyev 0:e056ac8fecf8 661 const unsigned char *input,
valeyev 0:e056ac8fecf8 662 unsigned char *output )
valeyev 0:e056ac8fecf8 663 {
valeyev 0:e056ac8fecf8 664 int ret;
valeyev 0:e056ac8fecf8 665 size_t olen;
valeyev 0:e056ac8fecf8 666 mbedtls_mpi T;
valeyev 0:e056ac8fecf8 667
valeyev 0:e056ac8fecf8 668 if( rsa_check_context( ctx, 0 /* public */, 0 /* no blinding */ ) )
valeyev 0:e056ac8fecf8 669 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 670
valeyev 0:e056ac8fecf8 671 mbedtls_mpi_init( &T );
valeyev 0:e056ac8fecf8 672
valeyev 0:e056ac8fecf8 673 #if defined(MBEDTLS_THREADING_C)
valeyev 0:e056ac8fecf8 674 if( ( ret = mbedtls_mutex_lock( &ctx->mutex ) ) != 0 )
valeyev 0:e056ac8fecf8 675 return( ret );
valeyev 0:e056ac8fecf8 676 #endif
valeyev 0:e056ac8fecf8 677
valeyev 0:e056ac8fecf8 678 MBEDTLS_MPI_CHK( mbedtls_mpi_read_binary( &T, input, ctx->len ) );
valeyev 0:e056ac8fecf8 679
valeyev 0:e056ac8fecf8 680 if( mbedtls_mpi_cmp_mpi( &T, &ctx->N ) >= 0 )
valeyev 0:e056ac8fecf8 681 {
valeyev 0:e056ac8fecf8 682 ret = MBEDTLS_ERR_MPI_BAD_INPUT_DATA;
valeyev 0:e056ac8fecf8 683 goto cleanup;
valeyev 0:e056ac8fecf8 684 }
valeyev 0:e056ac8fecf8 685
valeyev 0:e056ac8fecf8 686 olen = ctx->len;
valeyev 0:e056ac8fecf8 687 MBEDTLS_MPI_CHK( mbedtls_mpi_exp_mod( &T, &T, &ctx->E, &ctx->N, &ctx->RN ) );
valeyev 0:e056ac8fecf8 688 MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary( &T, output, olen ) );
valeyev 0:e056ac8fecf8 689
valeyev 0:e056ac8fecf8 690 cleanup:
valeyev 0:e056ac8fecf8 691 #if defined(MBEDTLS_THREADING_C)
valeyev 0:e056ac8fecf8 692 if( mbedtls_mutex_unlock( &ctx->mutex ) != 0 )
valeyev 0:e056ac8fecf8 693 return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
valeyev 0:e056ac8fecf8 694 #endif
valeyev 0:e056ac8fecf8 695
valeyev 0:e056ac8fecf8 696 mbedtls_mpi_free( &T );
valeyev 0:e056ac8fecf8 697
valeyev 0:e056ac8fecf8 698 if( ret != 0 )
valeyev 0:e056ac8fecf8 699 return( MBEDTLS_ERR_RSA_PUBLIC_FAILED + ret );
valeyev 0:e056ac8fecf8 700
valeyev 0:e056ac8fecf8 701 return( 0 );
valeyev 0:e056ac8fecf8 702 }
valeyev 0:e056ac8fecf8 703
valeyev 0:e056ac8fecf8 704 /*
valeyev 0:e056ac8fecf8 705 * Generate or update blinding values, see section 10 of:
valeyev 0:e056ac8fecf8 706 * KOCHER, Paul C. Timing attacks on implementations of Diffie-Hellman, RSA,
valeyev 0:e056ac8fecf8 707 * DSS, and other systems. In : Advances in Cryptology-CRYPTO'96. Springer
valeyev 0:e056ac8fecf8 708 * Berlin Heidelberg, 1996. p. 104-113.
valeyev 0:e056ac8fecf8 709 */
valeyev 0:e056ac8fecf8 710 static int rsa_prepare_blinding( mbedtls_rsa_context *ctx,
valeyev 0:e056ac8fecf8 711 int (*f_rng)(void *, unsigned char *, size_t), void *p_rng )
valeyev 0:e056ac8fecf8 712 {
valeyev 0:e056ac8fecf8 713 int ret, count = 0;
valeyev 0:e056ac8fecf8 714
valeyev 0:e056ac8fecf8 715 if( ctx->Vf.p != NULL )
valeyev 0:e056ac8fecf8 716 {
valeyev 0:e056ac8fecf8 717 /* We already have blinding values, just update them by squaring */
valeyev 0:e056ac8fecf8 718 MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &ctx->Vi, &ctx->Vi, &ctx->Vi ) );
valeyev 0:e056ac8fecf8 719 MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &ctx->Vi, &ctx->Vi, &ctx->N ) );
valeyev 0:e056ac8fecf8 720 MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &ctx->Vf, &ctx->Vf, &ctx->Vf ) );
valeyev 0:e056ac8fecf8 721 MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &ctx->Vf, &ctx->Vf, &ctx->N ) );
valeyev 0:e056ac8fecf8 722
valeyev 0:e056ac8fecf8 723 goto cleanup;
valeyev 0:e056ac8fecf8 724 }
valeyev 0:e056ac8fecf8 725
valeyev 0:e056ac8fecf8 726 /* Unblinding value: Vf = random number, invertible mod N */
valeyev 0:e056ac8fecf8 727 do {
valeyev 0:e056ac8fecf8 728 if( count++ > 10 )
valeyev 0:e056ac8fecf8 729 return( MBEDTLS_ERR_RSA_RNG_FAILED );
valeyev 0:e056ac8fecf8 730
valeyev 0:e056ac8fecf8 731 MBEDTLS_MPI_CHK( mbedtls_mpi_fill_random( &ctx->Vf, ctx->len - 1, f_rng, p_rng ) );
valeyev 0:e056ac8fecf8 732 MBEDTLS_MPI_CHK( mbedtls_mpi_gcd( &ctx->Vi, &ctx->Vf, &ctx->N ) );
valeyev 0:e056ac8fecf8 733 } while( mbedtls_mpi_cmp_int( &ctx->Vi, 1 ) != 0 );
valeyev 0:e056ac8fecf8 734
valeyev 0:e056ac8fecf8 735 /* Blinding value: Vi = Vf^(-e) mod N */
valeyev 0:e056ac8fecf8 736 MBEDTLS_MPI_CHK( mbedtls_mpi_inv_mod( &ctx->Vi, &ctx->Vf, &ctx->N ) );
valeyev 0:e056ac8fecf8 737 MBEDTLS_MPI_CHK( mbedtls_mpi_exp_mod( &ctx->Vi, &ctx->Vi, &ctx->E, &ctx->N, &ctx->RN ) );
valeyev 0:e056ac8fecf8 738
valeyev 0:e056ac8fecf8 739
valeyev 0:e056ac8fecf8 740 cleanup:
valeyev 0:e056ac8fecf8 741 return( ret );
valeyev 0:e056ac8fecf8 742 }
valeyev 0:e056ac8fecf8 743
valeyev 0:e056ac8fecf8 744 /*
valeyev 0:e056ac8fecf8 745 * Exponent blinding supposed to prevent side-channel attacks using multiple
valeyev 0:e056ac8fecf8 746 * traces of measurements to recover the RSA key. The more collisions are there,
valeyev 0:e056ac8fecf8 747 * the more bits of the key can be recovered. See [3].
valeyev 0:e056ac8fecf8 748 *
valeyev 0:e056ac8fecf8 749 * Collecting n collisions with m bit long blinding value requires 2^(m-m/n)
valeyev 0:e056ac8fecf8 750 * observations on avarage.
valeyev 0:e056ac8fecf8 751 *
valeyev 0:e056ac8fecf8 752 * For example with 28 byte blinding to achieve 2 collisions the adversary has
valeyev 0:e056ac8fecf8 753 * to make 2^112 observations on avarage.
valeyev 0:e056ac8fecf8 754 *
valeyev 0:e056ac8fecf8 755 * (With the currently (as of 2017 April) known best algorithms breaking 2048
valeyev 0:e056ac8fecf8 756 * bit RSA requires approximately as much time as trying out 2^112 random keys.
valeyev 0:e056ac8fecf8 757 * Thus in this sense with 28 byte blinding the security is not reduced by
valeyev 0:e056ac8fecf8 758 * side-channel attacks like the one in [3])
valeyev 0:e056ac8fecf8 759 *
valeyev 0:e056ac8fecf8 760 * This countermeasure does not help if the key recovery is possible with a
valeyev 0:e056ac8fecf8 761 * single trace.
valeyev 0:e056ac8fecf8 762 */
valeyev 0:e056ac8fecf8 763 #define RSA_EXPONENT_BLINDING 28
valeyev 0:e056ac8fecf8 764
valeyev 0:e056ac8fecf8 765 /*
valeyev 0:e056ac8fecf8 766 * Do an RSA private key operation
valeyev 0:e056ac8fecf8 767 */
valeyev 0:e056ac8fecf8 768 int mbedtls_rsa_private( mbedtls_rsa_context *ctx,
valeyev 0:e056ac8fecf8 769 int (*f_rng)(void *, unsigned char *, size_t),
valeyev 0:e056ac8fecf8 770 void *p_rng,
valeyev 0:e056ac8fecf8 771 const unsigned char *input,
valeyev 0:e056ac8fecf8 772 unsigned char *output )
valeyev 0:e056ac8fecf8 773 {
valeyev 0:e056ac8fecf8 774 int ret;
valeyev 0:e056ac8fecf8 775 size_t olen;
valeyev 0:e056ac8fecf8 776 mbedtls_mpi T, T1, T2;
valeyev 0:e056ac8fecf8 777 mbedtls_mpi P1, Q1, R;
valeyev 0:e056ac8fecf8 778 #if defined(MBEDTLS_RSA_NO_CRT)
valeyev 0:e056ac8fecf8 779 mbedtls_mpi D_blind;
valeyev 0:e056ac8fecf8 780 mbedtls_mpi *D = &ctx->D;
valeyev 0:e056ac8fecf8 781 #else
valeyev 0:e056ac8fecf8 782 mbedtls_mpi DP_blind, DQ_blind;
valeyev 0:e056ac8fecf8 783 mbedtls_mpi *DP = &ctx->DP;
valeyev 0:e056ac8fecf8 784 mbedtls_mpi *DQ = &ctx->DQ;
valeyev 0:e056ac8fecf8 785 #endif
valeyev 0:e056ac8fecf8 786
valeyev 0:e056ac8fecf8 787 if( rsa_check_context( ctx, 1 /* private key checks */,
valeyev 0:e056ac8fecf8 788 f_rng != NULL /* blinding y/n */ ) != 0 )
valeyev 0:e056ac8fecf8 789 {
valeyev 0:e056ac8fecf8 790 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 791 }
valeyev 0:e056ac8fecf8 792
valeyev 0:e056ac8fecf8 793 mbedtls_mpi_init( &T ); mbedtls_mpi_init( &T1 ); mbedtls_mpi_init( &T2 );
valeyev 0:e056ac8fecf8 794 mbedtls_mpi_init( &P1 ); mbedtls_mpi_init( &Q1 ); mbedtls_mpi_init( &R );
valeyev 0:e056ac8fecf8 795
valeyev 0:e056ac8fecf8 796 if( f_rng != NULL )
valeyev 0:e056ac8fecf8 797 {
valeyev 0:e056ac8fecf8 798 #if defined(MBEDTLS_RSA_NO_CRT)
valeyev 0:e056ac8fecf8 799 mbedtls_mpi_init( &D_blind );
valeyev 0:e056ac8fecf8 800 #else
valeyev 0:e056ac8fecf8 801 mbedtls_mpi_init( &DP_blind );
valeyev 0:e056ac8fecf8 802 mbedtls_mpi_init( &DQ_blind );
valeyev 0:e056ac8fecf8 803 #endif
valeyev 0:e056ac8fecf8 804 }
valeyev 0:e056ac8fecf8 805
valeyev 0:e056ac8fecf8 806
valeyev 0:e056ac8fecf8 807 #if defined(MBEDTLS_THREADING_C)
valeyev 0:e056ac8fecf8 808 if( ( ret = mbedtls_mutex_lock( &ctx->mutex ) ) != 0 )
valeyev 0:e056ac8fecf8 809 return( ret );
valeyev 0:e056ac8fecf8 810 #endif
valeyev 0:e056ac8fecf8 811
valeyev 0:e056ac8fecf8 812 MBEDTLS_MPI_CHK( mbedtls_mpi_read_binary( &T, input, ctx->len ) );
valeyev 0:e056ac8fecf8 813 if( mbedtls_mpi_cmp_mpi( &T, &ctx->N ) >= 0 )
valeyev 0:e056ac8fecf8 814 {
valeyev 0:e056ac8fecf8 815 ret = MBEDTLS_ERR_MPI_BAD_INPUT_DATA;
valeyev 0:e056ac8fecf8 816 goto cleanup;
valeyev 0:e056ac8fecf8 817 }
valeyev 0:e056ac8fecf8 818
valeyev 0:e056ac8fecf8 819 if( f_rng != NULL )
valeyev 0:e056ac8fecf8 820 {
valeyev 0:e056ac8fecf8 821 /*
valeyev 0:e056ac8fecf8 822 * Blinding
valeyev 0:e056ac8fecf8 823 * T = T * Vi mod N
valeyev 0:e056ac8fecf8 824 */
valeyev 0:e056ac8fecf8 825 MBEDTLS_MPI_CHK( rsa_prepare_blinding( ctx, f_rng, p_rng ) );
valeyev 0:e056ac8fecf8 826 MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &T, &T, &ctx->Vi ) );
valeyev 0:e056ac8fecf8 827 MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &T, &T, &ctx->N ) );
valeyev 0:e056ac8fecf8 828
valeyev 0:e056ac8fecf8 829 /*
valeyev 0:e056ac8fecf8 830 * Exponent blinding
valeyev 0:e056ac8fecf8 831 */
valeyev 0:e056ac8fecf8 832 MBEDTLS_MPI_CHK( mbedtls_mpi_sub_int( &P1, &ctx->P, 1 ) );
valeyev 0:e056ac8fecf8 833 MBEDTLS_MPI_CHK( mbedtls_mpi_sub_int( &Q1, &ctx->Q, 1 ) );
valeyev 0:e056ac8fecf8 834
valeyev 0:e056ac8fecf8 835 #if defined(MBEDTLS_RSA_NO_CRT)
valeyev 0:e056ac8fecf8 836 /*
valeyev 0:e056ac8fecf8 837 * D_blind = ( P - 1 ) * ( Q - 1 ) * R + D
valeyev 0:e056ac8fecf8 838 */
valeyev 0:e056ac8fecf8 839 MBEDTLS_MPI_CHK( mbedtls_mpi_fill_random( &R, RSA_EXPONENT_BLINDING,
valeyev 0:e056ac8fecf8 840 f_rng, p_rng ) );
valeyev 0:e056ac8fecf8 841 MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &D_blind, &P1, &Q1 ) );
valeyev 0:e056ac8fecf8 842 MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &D_blind, &D_blind, &R ) );
valeyev 0:e056ac8fecf8 843 MBEDTLS_MPI_CHK( mbedtls_mpi_add_mpi( &D_blind, &D_blind, &ctx->D ) );
valeyev 0:e056ac8fecf8 844
valeyev 0:e056ac8fecf8 845 D = &D_blind;
valeyev 0:e056ac8fecf8 846 #else
valeyev 0:e056ac8fecf8 847 /*
valeyev 0:e056ac8fecf8 848 * DP_blind = ( P - 1 ) * R + DP
valeyev 0:e056ac8fecf8 849 */
valeyev 0:e056ac8fecf8 850 MBEDTLS_MPI_CHK( mbedtls_mpi_fill_random( &R, RSA_EXPONENT_BLINDING,
valeyev 0:e056ac8fecf8 851 f_rng, p_rng ) );
valeyev 0:e056ac8fecf8 852 MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &DP_blind, &P1, &R ) );
valeyev 0:e056ac8fecf8 853 MBEDTLS_MPI_CHK( mbedtls_mpi_add_mpi( &DP_blind, &DP_blind,
valeyev 0:e056ac8fecf8 854 &ctx->DP ) );
valeyev 0:e056ac8fecf8 855
valeyev 0:e056ac8fecf8 856 DP = &DP_blind;
valeyev 0:e056ac8fecf8 857
valeyev 0:e056ac8fecf8 858 /*
valeyev 0:e056ac8fecf8 859 * DQ_blind = ( Q - 1 ) * R + DQ
valeyev 0:e056ac8fecf8 860 */
valeyev 0:e056ac8fecf8 861 MBEDTLS_MPI_CHK( mbedtls_mpi_fill_random( &R, RSA_EXPONENT_BLINDING,
valeyev 0:e056ac8fecf8 862 f_rng, p_rng ) );
valeyev 0:e056ac8fecf8 863 MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &DQ_blind, &Q1, &R ) );
valeyev 0:e056ac8fecf8 864 MBEDTLS_MPI_CHK( mbedtls_mpi_add_mpi( &DQ_blind, &DQ_blind,
valeyev 0:e056ac8fecf8 865 &ctx->DQ ) );
valeyev 0:e056ac8fecf8 866
valeyev 0:e056ac8fecf8 867 DQ = &DQ_blind;
valeyev 0:e056ac8fecf8 868 #endif /* MBEDTLS_RSA_NO_CRT */
valeyev 0:e056ac8fecf8 869 }
valeyev 0:e056ac8fecf8 870
valeyev 0:e056ac8fecf8 871 #if defined(MBEDTLS_RSA_NO_CRT)
valeyev 0:e056ac8fecf8 872 MBEDTLS_MPI_CHK( mbedtls_mpi_exp_mod( &T, &T, D, &ctx->N, &ctx->RN ) );
valeyev 0:e056ac8fecf8 873 #else
valeyev 0:e056ac8fecf8 874 /*
valeyev 0:e056ac8fecf8 875 * Faster decryption using the CRT
valeyev 0:e056ac8fecf8 876 *
valeyev 0:e056ac8fecf8 877 * T1 = input ^ dP mod P
valeyev 0:e056ac8fecf8 878 * T2 = input ^ dQ mod Q
valeyev 0:e056ac8fecf8 879 */
valeyev 0:e056ac8fecf8 880 MBEDTLS_MPI_CHK( mbedtls_mpi_exp_mod( &T1, &T, DP, &ctx->P, &ctx->RP ) );
valeyev 0:e056ac8fecf8 881 MBEDTLS_MPI_CHK( mbedtls_mpi_exp_mod( &T2, &T, DQ, &ctx->Q, &ctx->RQ ) );
valeyev 0:e056ac8fecf8 882
valeyev 0:e056ac8fecf8 883 /*
valeyev 0:e056ac8fecf8 884 * T = (T1 - T2) * (Q^-1 mod P) mod P
valeyev 0:e056ac8fecf8 885 */
valeyev 0:e056ac8fecf8 886 MBEDTLS_MPI_CHK( mbedtls_mpi_sub_mpi( &T, &T1, &T2 ) );
valeyev 0:e056ac8fecf8 887 MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &T1, &T, &ctx->QP ) );
valeyev 0:e056ac8fecf8 888 MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &T, &T1, &ctx->P ) );
valeyev 0:e056ac8fecf8 889
valeyev 0:e056ac8fecf8 890 /*
valeyev 0:e056ac8fecf8 891 * T = T2 + T * Q
valeyev 0:e056ac8fecf8 892 */
valeyev 0:e056ac8fecf8 893 MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &T1, &T, &ctx->Q ) );
valeyev 0:e056ac8fecf8 894 MBEDTLS_MPI_CHK( mbedtls_mpi_add_mpi( &T, &T2, &T1 ) );
valeyev 0:e056ac8fecf8 895 #endif /* MBEDTLS_RSA_NO_CRT */
valeyev 0:e056ac8fecf8 896
valeyev 0:e056ac8fecf8 897 if( f_rng != NULL )
valeyev 0:e056ac8fecf8 898 {
valeyev 0:e056ac8fecf8 899 /*
valeyev 0:e056ac8fecf8 900 * Unblind
valeyev 0:e056ac8fecf8 901 * T = T * Vf mod N
valeyev 0:e056ac8fecf8 902 */
valeyev 0:e056ac8fecf8 903 MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &T, &T, &ctx->Vf ) );
valeyev 0:e056ac8fecf8 904 MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &T, &T, &ctx->N ) );
valeyev 0:e056ac8fecf8 905 }
valeyev 0:e056ac8fecf8 906
valeyev 0:e056ac8fecf8 907 olen = ctx->len;
valeyev 0:e056ac8fecf8 908 MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary( &T, output, olen ) );
valeyev 0:e056ac8fecf8 909
valeyev 0:e056ac8fecf8 910 cleanup:
valeyev 0:e056ac8fecf8 911 #if defined(MBEDTLS_THREADING_C)
valeyev 0:e056ac8fecf8 912 if( mbedtls_mutex_unlock( &ctx->mutex ) != 0 )
valeyev 0:e056ac8fecf8 913 return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
valeyev 0:e056ac8fecf8 914 #endif
valeyev 0:e056ac8fecf8 915
valeyev 0:e056ac8fecf8 916 mbedtls_mpi_free( &T ); mbedtls_mpi_free( &T1 ); mbedtls_mpi_free( &T2 );
valeyev 0:e056ac8fecf8 917 mbedtls_mpi_free( &P1 ); mbedtls_mpi_free( &Q1 ); mbedtls_mpi_free( &R );
valeyev 0:e056ac8fecf8 918
valeyev 0:e056ac8fecf8 919 if( f_rng != NULL )
valeyev 0:e056ac8fecf8 920 {
valeyev 0:e056ac8fecf8 921 #if defined(MBEDTLS_RSA_NO_CRT)
valeyev 0:e056ac8fecf8 922 mbedtls_mpi_free( &D_blind );
valeyev 0:e056ac8fecf8 923 #else
valeyev 0:e056ac8fecf8 924 mbedtls_mpi_free( &DP_blind );
valeyev 0:e056ac8fecf8 925 mbedtls_mpi_free( &DQ_blind );
valeyev 0:e056ac8fecf8 926 #endif
valeyev 0:e056ac8fecf8 927 }
valeyev 0:e056ac8fecf8 928
valeyev 0:e056ac8fecf8 929 if( ret != 0 )
valeyev 0:e056ac8fecf8 930 return( MBEDTLS_ERR_RSA_PRIVATE_FAILED + ret );
valeyev 0:e056ac8fecf8 931
valeyev 0:e056ac8fecf8 932 return( 0 );
valeyev 0:e056ac8fecf8 933 }
valeyev 0:e056ac8fecf8 934
valeyev 0:e056ac8fecf8 935 #if defined(MBEDTLS_PKCS1_V21)
valeyev 0:e056ac8fecf8 936 /**
valeyev 0:e056ac8fecf8 937 * Generate and apply the MGF1 operation (from PKCS#1 v2.1) to a buffer.
valeyev 0:e056ac8fecf8 938 *
valeyev 0:e056ac8fecf8 939 * \param dst buffer to mask
valeyev 0:e056ac8fecf8 940 * \param dlen length of destination buffer
valeyev 0:e056ac8fecf8 941 * \param src source of the mask generation
valeyev 0:e056ac8fecf8 942 * \param slen length of the source buffer
valeyev 0:e056ac8fecf8 943 * \param md_ctx message digest context to use
valeyev 0:e056ac8fecf8 944 */
valeyev 0:e056ac8fecf8 945 static int mgf_mask( unsigned char *dst, size_t dlen, unsigned char *src,
valeyev 0:e056ac8fecf8 946 size_t slen, mbedtls_md_context_t *md_ctx )
valeyev 0:e056ac8fecf8 947 {
valeyev 0:e056ac8fecf8 948 unsigned char mask[MBEDTLS_MD_MAX_SIZE];
valeyev 0:e056ac8fecf8 949 unsigned char counter[4];
valeyev 0:e056ac8fecf8 950 unsigned char *p;
valeyev 0:e056ac8fecf8 951 unsigned int hlen;
valeyev 0:e056ac8fecf8 952 size_t i, use_len;
valeyev 0:e056ac8fecf8 953 int ret = 0;
valeyev 0:e056ac8fecf8 954
valeyev 0:e056ac8fecf8 955 memset( mask, 0, MBEDTLS_MD_MAX_SIZE );
valeyev 0:e056ac8fecf8 956 memset( counter, 0, 4 );
valeyev 0:e056ac8fecf8 957
valeyev 0:e056ac8fecf8 958 hlen = mbedtls_md_get_size( md_ctx->md_info );
valeyev 0:e056ac8fecf8 959
valeyev 0:e056ac8fecf8 960 /* Generate and apply dbMask */
valeyev 0:e056ac8fecf8 961 p = dst;
valeyev 0:e056ac8fecf8 962
valeyev 0:e056ac8fecf8 963 while( dlen > 0 )
valeyev 0:e056ac8fecf8 964 {
valeyev 0:e056ac8fecf8 965 use_len = hlen;
valeyev 0:e056ac8fecf8 966 if( dlen < hlen )
valeyev 0:e056ac8fecf8 967 use_len = dlen;
valeyev 0:e056ac8fecf8 968
valeyev 0:e056ac8fecf8 969 if( ( ret = mbedtls_md_starts( md_ctx ) ) != 0 )
valeyev 0:e056ac8fecf8 970 goto exit;
valeyev 0:e056ac8fecf8 971 if( ( ret = mbedtls_md_update( md_ctx, src, slen ) ) != 0 )
valeyev 0:e056ac8fecf8 972 goto exit;
valeyev 0:e056ac8fecf8 973 if( ( ret = mbedtls_md_update( md_ctx, counter, 4 ) ) != 0 )
valeyev 0:e056ac8fecf8 974 goto exit;
valeyev 0:e056ac8fecf8 975 if( ( ret = mbedtls_md_finish( md_ctx, mask ) ) != 0 )
valeyev 0:e056ac8fecf8 976 goto exit;
valeyev 0:e056ac8fecf8 977
valeyev 0:e056ac8fecf8 978 for( i = 0; i < use_len; ++i )
valeyev 0:e056ac8fecf8 979 *p++ ^= mask[i];
valeyev 0:e056ac8fecf8 980
valeyev 0:e056ac8fecf8 981 counter[3]++;
valeyev 0:e056ac8fecf8 982
valeyev 0:e056ac8fecf8 983 dlen -= use_len;
valeyev 0:e056ac8fecf8 984 }
valeyev 0:e056ac8fecf8 985
valeyev 0:e056ac8fecf8 986 exit:
valeyev 0:e056ac8fecf8 987 mbedtls_zeroize( mask, sizeof( mask ) );
valeyev 0:e056ac8fecf8 988
valeyev 0:e056ac8fecf8 989 return( ret );
valeyev 0:e056ac8fecf8 990 }
valeyev 0:e056ac8fecf8 991 #endif /* MBEDTLS_PKCS1_V21 */
valeyev 0:e056ac8fecf8 992
valeyev 0:e056ac8fecf8 993 #if defined(MBEDTLS_PKCS1_V21)
valeyev 0:e056ac8fecf8 994 /*
valeyev 0:e056ac8fecf8 995 * Implementation of the PKCS#1 v2.1 RSAES-OAEP-ENCRYPT function
valeyev 0:e056ac8fecf8 996 */
valeyev 0:e056ac8fecf8 997 int mbedtls_rsa_rsaes_oaep_encrypt( mbedtls_rsa_context *ctx,
valeyev 0:e056ac8fecf8 998 int (*f_rng)(void *, unsigned char *, size_t),
valeyev 0:e056ac8fecf8 999 void *p_rng,
valeyev 0:e056ac8fecf8 1000 int mode,
valeyev 0:e056ac8fecf8 1001 const unsigned char *label, size_t label_len,
valeyev 0:e056ac8fecf8 1002 size_t ilen,
valeyev 0:e056ac8fecf8 1003 const unsigned char *input,
valeyev 0:e056ac8fecf8 1004 unsigned char *output )
valeyev 0:e056ac8fecf8 1005 {
valeyev 0:e056ac8fecf8 1006 size_t olen;
valeyev 0:e056ac8fecf8 1007 int ret;
valeyev 0:e056ac8fecf8 1008 unsigned char *p = output;
valeyev 0:e056ac8fecf8 1009 unsigned int hlen;
valeyev 0:e056ac8fecf8 1010 const mbedtls_md_info_t *md_info;
valeyev 0:e056ac8fecf8 1011 mbedtls_md_context_t md_ctx;
valeyev 0:e056ac8fecf8 1012
valeyev 0:e056ac8fecf8 1013 if( mode == MBEDTLS_RSA_PRIVATE && ctx->padding != MBEDTLS_RSA_PKCS_V21 )
valeyev 0:e056ac8fecf8 1014 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 1015
valeyev 0:e056ac8fecf8 1016 if( f_rng == NULL )
valeyev 0:e056ac8fecf8 1017 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 1018
valeyev 0:e056ac8fecf8 1019 md_info = mbedtls_md_info_from_type( (mbedtls_md_type_t) ctx->hash_id );
valeyev 0:e056ac8fecf8 1020 if( md_info == NULL )
valeyev 0:e056ac8fecf8 1021 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 1022
valeyev 0:e056ac8fecf8 1023 olen = ctx->len;
valeyev 0:e056ac8fecf8 1024 hlen = mbedtls_md_get_size( md_info );
valeyev 0:e056ac8fecf8 1025
valeyev 0:e056ac8fecf8 1026 /* first comparison checks for overflow */
valeyev 0:e056ac8fecf8 1027 if( ilen + 2 * hlen + 2 < ilen || olen < ilen + 2 * hlen + 2 )
valeyev 0:e056ac8fecf8 1028 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 1029
valeyev 0:e056ac8fecf8 1030 memset( output, 0, olen );
valeyev 0:e056ac8fecf8 1031
valeyev 0:e056ac8fecf8 1032 *p++ = 0;
valeyev 0:e056ac8fecf8 1033
valeyev 0:e056ac8fecf8 1034 /* Generate a random octet string seed */
valeyev 0:e056ac8fecf8 1035 if( ( ret = f_rng( p_rng, p, hlen ) ) != 0 )
valeyev 0:e056ac8fecf8 1036 return( MBEDTLS_ERR_RSA_RNG_FAILED + ret );
valeyev 0:e056ac8fecf8 1037
valeyev 0:e056ac8fecf8 1038 p += hlen;
valeyev 0:e056ac8fecf8 1039
valeyev 0:e056ac8fecf8 1040 /* Construct DB */
valeyev 0:e056ac8fecf8 1041 if( ( ret = mbedtls_md( md_info, label, label_len, p ) ) != 0 )
valeyev 0:e056ac8fecf8 1042 return( ret );
valeyev 0:e056ac8fecf8 1043 p += hlen;
valeyev 0:e056ac8fecf8 1044 p += olen - 2 * hlen - 2 - ilen;
valeyev 0:e056ac8fecf8 1045 *p++ = 1;
valeyev 0:e056ac8fecf8 1046 memcpy( p, input, ilen );
valeyev 0:e056ac8fecf8 1047
valeyev 0:e056ac8fecf8 1048 mbedtls_md_init( &md_ctx );
valeyev 0:e056ac8fecf8 1049 if( ( ret = mbedtls_md_setup( &md_ctx, md_info, 0 ) ) != 0 )
valeyev 0:e056ac8fecf8 1050 goto exit;
valeyev 0:e056ac8fecf8 1051
valeyev 0:e056ac8fecf8 1052 /* maskedDB: Apply dbMask to DB */
valeyev 0:e056ac8fecf8 1053 if( ( ret = mgf_mask( output + hlen + 1, olen - hlen - 1, output + 1, hlen,
valeyev 0:e056ac8fecf8 1054 &md_ctx ) ) != 0 )
valeyev 0:e056ac8fecf8 1055 goto exit;
valeyev 0:e056ac8fecf8 1056
valeyev 0:e056ac8fecf8 1057 /* maskedSeed: Apply seedMask to seed */
valeyev 0:e056ac8fecf8 1058 if( ( ret = mgf_mask( output + 1, hlen, output + hlen + 1, olen - hlen - 1,
valeyev 0:e056ac8fecf8 1059 &md_ctx ) ) != 0 )
valeyev 0:e056ac8fecf8 1060 goto exit;
valeyev 0:e056ac8fecf8 1061
valeyev 0:e056ac8fecf8 1062 exit:
valeyev 0:e056ac8fecf8 1063 mbedtls_md_free( &md_ctx );
valeyev 0:e056ac8fecf8 1064
valeyev 0:e056ac8fecf8 1065 if( ret != 0 )
valeyev 0:e056ac8fecf8 1066 return( ret );
valeyev 0:e056ac8fecf8 1067
valeyev 0:e056ac8fecf8 1068 return( ( mode == MBEDTLS_RSA_PUBLIC )
valeyev 0:e056ac8fecf8 1069 ? mbedtls_rsa_public( ctx, output, output )
valeyev 0:e056ac8fecf8 1070 : mbedtls_rsa_private( ctx, f_rng, p_rng, output, output ) );
valeyev 0:e056ac8fecf8 1071 }
valeyev 0:e056ac8fecf8 1072 #endif /* MBEDTLS_PKCS1_V21 */
valeyev 0:e056ac8fecf8 1073
valeyev 0:e056ac8fecf8 1074 #if defined(MBEDTLS_PKCS1_V15)
valeyev 0:e056ac8fecf8 1075 /*
valeyev 0:e056ac8fecf8 1076 * Implementation of the PKCS#1 v2.1 RSAES-PKCS1-V1_5-ENCRYPT function
valeyev 0:e056ac8fecf8 1077 */
valeyev 0:e056ac8fecf8 1078 int mbedtls_rsa_rsaes_pkcs1_v15_encrypt( mbedtls_rsa_context *ctx,
valeyev 0:e056ac8fecf8 1079 int (*f_rng)(void *, unsigned char *, size_t),
valeyev 0:e056ac8fecf8 1080 void *p_rng,
valeyev 0:e056ac8fecf8 1081 int mode, size_t ilen,
valeyev 0:e056ac8fecf8 1082 const unsigned char *input,
valeyev 0:e056ac8fecf8 1083 unsigned char *output )
valeyev 0:e056ac8fecf8 1084 {
valeyev 0:e056ac8fecf8 1085 size_t nb_pad, olen;
valeyev 0:e056ac8fecf8 1086 int ret;
valeyev 0:e056ac8fecf8 1087 unsigned char *p = output;
valeyev 0:e056ac8fecf8 1088
valeyev 0:e056ac8fecf8 1089 if( mode == MBEDTLS_RSA_PRIVATE && ctx->padding != MBEDTLS_RSA_PKCS_V15 )
valeyev 0:e056ac8fecf8 1090 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 1091
valeyev 0:e056ac8fecf8 1092 // We don't check p_rng because it won't be dereferenced here
valeyev 0:e056ac8fecf8 1093 if( f_rng == NULL || input == NULL || output == NULL )
valeyev 0:e056ac8fecf8 1094 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 1095
valeyev 0:e056ac8fecf8 1096 olen = ctx->len;
valeyev 0:e056ac8fecf8 1097
valeyev 0:e056ac8fecf8 1098 /* first comparison checks for overflow */
valeyev 0:e056ac8fecf8 1099 if( ilen + 11 < ilen || olen < ilen + 11 )
valeyev 0:e056ac8fecf8 1100 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 1101
valeyev 0:e056ac8fecf8 1102 nb_pad = olen - 3 - ilen;
valeyev 0:e056ac8fecf8 1103
valeyev 0:e056ac8fecf8 1104 *p++ = 0;
valeyev 0:e056ac8fecf8 1105 if( mode == MBEDTLS_RSA_PUBLIC )
valeyev 0:e056ac8fecf8 1106 {
valeyev 0:e056ac8fecf8 1107 *p++ = MBEDTLS_RSA_CRYPT;
valeyev 0:e056ac8fecf8 1108
valeyev 0:e056ac8fecf8 1109 while( nb_pad-- > 0 )
valeyev 0:e056ac8fecf8 1110 {
valeyev 0:e056ac8fecf8 1111 int rng_dl = 100;
valeyev 0:e056ac8fecf8 1112
valeyev 0:e056ac8fecf8 1113 do {
valeyev 0:e056ac8fecf8 1114 ret = f_rng( p_rng, p, 1 );
valeyev 0:e056ac8fecf8 1115 } while( *p == 0 && --rng_dl && ret == 0 );
valeyev 0:e056ac8fecf8 1116
valeyev 0:e056ac8fecf8 1117 /* Check if RNG failed to generate data */
valeyev 0:e056ac8fecf8 1118 if( rng_dl == 0 || ret != 0 )
valeyev 0:e056ac8fecf8 1119 return( MBEDTLS_ERR_RSA_RNG_FAILED + ret );
valeyev 0:e056ac8fecf8 1120
valeyev 0:e056ac8fecf8 1121 p++;
valeyev 0:e056ac8fecf8 1122 }
valeyev 0:e056ac8fecf8 1123 }
valeyev 0:e056ac8fecf8 1124 else
valeyev 0:e056ac8fecf8 1125 {
valeyev 0:e056ac8fecf8 1126 *p++ = MBEDTLS_RSA_SIGN;
valeyev 0:e056ac8fecf8 1127
valeyev 0:e056ac8fecf8 1128 while( nb_pad-- > 0 )
valeyev 0:e056ac8fecf8 1129 *p++ = 0xFF;
valeyev 0:e056ac8fecf8 1130 }
valeyev 0:e056ac8fecf8 1131
valeyev 0:e056ac8fecf8 1132 *p++ = 0;
valeyev 0:e056ac8fecf8 1133 memcpy( p, input, ilen );
valeyev 0:e056ac8fecf8 1134
valeyev 0:e056ac8fecf8 1135 return( ( mode == MBEDTLS_RSA_PUBLIC )
valeyev 0:e056ac8fecf8 1136 ? mbedtls_rsa_public( ctx, output, output )
valeyev 0:e056ac8fecf8 1137 : mbedtls_rsa_private( ctx, f_rng, p_rng, output, output ) );
valeyev 0:e056ac8fecf8 1138 }
valeyev 0:e056ac8fecf8 1139 #endif /* MBEDTLS_PKCS1_V15 */
valeyev 0:e056ac8fecf8 1140
valeyev 0:e056ac8fecf8 1141 /*
valeyev 0:e056ac8fecf8 1142 * Add the message padding, then do an RSA operation
valeyev 0:e056ac8fecf8 1143 */
valeyev 0:e056ac8fecf8 1144 int mbedtls_rsa_pkcs1_encrypt( mbedtls_rsa_context *ctx,
valeyev 0:e056ac8fecf8 1145 int (*f_rng)(void *, unsigned char *, size_t),
valeyev 0:e056ac8fecf8 1146 void *p_rng,
valeyev 0:e056ac8fecf8 1147 int mode, size_t ilen,
valeyev 0:e056ac8fecf8 1148 const unsigned char *input,
valeyev 0:e056ac8fecf8 1149 unsigned char *output )
valeyev 0:e056ac8fecf8 1150 {
valeyev 0:e056ac8fecf8 1151 switch( ctx->padding )
valeyev 0:e056ac8fecf8 1152 {
valeyev 0:e056ac8fecf8 1153 #if defined(MBEDTLS_PKCS1_V15)
valeyev 0:e056ac8fecf8 1154 case MBEDTLS_RSA_PKCS_V15:
valeyev 0:e056ac8fecf8 1155 return mbedtls_rsa_rsaes_pkcs1_v15_encrypt( ctx, f_rng, p_rng, mode, ilen,
valeyev 0:e056ac8fecf8 1156 input, output );
valeyev 0:e056ac8fecf8 1157 #endif
valeyev 0:e056ac8fecf8 1158
valeyev 0:e056ac8fecf8 1159 #if defined(MBEDTLS_PKCS1_V21)
valeyev 0:e056ac8fecf8 1160 case MBEDTLS_RSA_PKCS_V21:
valeyev 0:e056ac8fecf8 1161 return mbedtls_rsa_rsaes_oaep_encrypt( ctx, f_rng, p_rng, mode, NULL, 0,
valeyev 0:e056ac8fecf8 1162 ilen, input, output );
valeyev 0:e056ac8fecf8 1163 #endif
valeyev 0:e056ac8fecf8 1164
valeyev 0:e056ac8fecf8 1165 default:
valeyev 0:e056ac8fecf8 1166 return( MBEDTLS_ERR_RSA_INVALID_PADDING );
valeyev 0:e056ac8fecf8 1167 }
valeyev 0:e056ac8fecf8 1168 }
valeyev 0:e056ac8fecf8 1169
valeyev 0:e056ac8fecf8 1170 #if defined(MBEDTLS_PKCS1_V21)
valeyev 0:e056ac8fecf8 1171 /*
valeyev 0:e056ac8fecf8 1172 * Implementation of the PKCS#1 v2.1 RSAES-OAEP-DECRYPT function
valeyev 0:e056ac8fecf8 1173 */
valeyev 0:e056ac8fecf8 1174 int mbedtls_rsa_rsaes_oaep_decrypt( mbedtls_rsa_context *ctx,
valeyev 0:e056ac8fecf8 1175 int (*f_rng)(void *, unsigned char *, size_t),
valeyev 0:e056ac8fecf8 1176 void *p_rng,
valeyev 0:e056ac8fecf8 1177 int mode,
valeyev 0:e056ac8fecf8 1178 const unsigned char *label, size_t label_len,
valeyev 0:e056ac8fecf8 1179 size_t *olen,
valeyev 0:e056ac8fecf8 1180 const unsigned char *input,
valeyev 0:e056ac8fecf8 1181 unsigned char *output,
valeyev 0:e056ac8fecf8 1182 size_t output_max_len )
valeyev 0:e056ac8fecf8 1183 {
valeyev 0:e056ac8fecf8 1184 int ret;
valeyev 0:e056ac8fecf8 1185 size_t ilen, i, pad_len;
valeyev 0:e056ac8fecf8 1186 unsigned char *p, bad, pad_done;
valeyev 0:e056ac8fecf8 1187 unsigned char buf[MBEDTLS_MPI_MAX_SIZE];
valeyev 0:e056ac8fecf8 1188 unsigned char lhash[MBEDTLS_MD_MAX_SIZE];
valeyev 0:e056ac8fecf8 1189 unsigned int hlen;
valeyev 0:e056ac8fecf8 1190 const mbedtls_md_info_t *md_info;
valeyev 0:e056ac8fecf8 1191 mbedtls_md_context_t md_ctx;
valeyev 0:e056ac8fecf8 1192
valeyev 0:e056ac8fecf8 1193 /*
valeyev 0:e056ac8fecf8 1194 * Parameters sanity checks
valeyev 0:e056ac8fecf8 1195 */
valeyev 0:e056ac8fecf8 1196 if( mode == MBEDTLS_RSA_PRIVATE && ctx->padding != MBEDTLS_RSA_PKCS_V21 )
valeyev 0:e056ac8fecf8 1197 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 1198
valeyev 0:e056ac8fecf8 1199 ilen = ctx->len;
valeyev 0:e056ac8fecf8 1200
valeyev 0:e056ac8fecf8 1201 if( ilen < 16 || ilen > sizeof( buf ) )
valeyev 0:e056ac8fecf8 1202 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 1203
valeyev 0:e056ac8fecf8 1204 md_info = mbedtls_md_info_from_type( (mbedtls_md_type_t) ctx->hash_id );
valeyev 0:e056ac8fecf8 1205 if( md_info == NULL )
valeyev 0:e056ac8fecf8 1206 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 1207
valeyev 0:e056ac8fecf8 1208 hlen = mbedtls_md_get_size( md_info );
valeyev 0:e056ac8fecf8 1209
valeyev 0:e056ac8fecf8 1210 // checking for integer underflow
valeyev 0:e056ac8fecf8 1211 if( 2 * hlen + 2 > ilen )
valeyev 0:e056ac8fecf8 1212 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 1213
valeyev 0:e056ac8fecf8 1214 /*
valeyev 0:e056ac8fecf8 1215 * RSA operation
valeyev 0:e056ac8fecf8 1216 */
valeyev 0:e056ac8fecf8 1217 ret = ( mode == MBEDTLS_RSA_PUBLIC )
valeyev 0:e056ac8fecf8 1218 ? mbedtls_rsa_public( ctx, input, buf )
valeyev 0:e056ac8fecf8 1219 : mbedtls_rsa_private( ctx, f_rng, p_rng, input, buf );
valeyev 0:e056ac8fecf8 1220
valeyev 0:e056ac8fecf8 1221 if( ret != 0 )
valeyev 0:e056ac8fecf8 1222 goto cleanup;
valeyev 0:e056ac8fecf8 1223
valeyev 0:e056ac8fecf8 1224 /*
valeyev 0:e056ac8fecf8 1225 * Unmask data and generate lHash
valeyev 0:e056ac8fecf8 1226 */
valeyev 0:e056ac8fecf8 1227 mbedtls_md_init( &md_ctx );
valeyev 0:e056ac8fecf8 1228 if( ( ret = mbedtls_md_setup( &md_ctx, md_info, 0 ) ) != 0 )
valeyev 0:e056ac8fecf8 1229 {
valeyev 0:e056ac8fecf8 1230 mbedtls_md_free( &md_ctx );
valeyev 0:e056ac8fecf8 1231 goto cleanup;
valeyev 0:e056ac8fecf8 1232 }
valeyev 0:e056ac8fecf8 1233
valeyev 0:e056ac8fecf8 1234 /* seed: Apply seedMask to maskedSeed */
valeyev 0:e056ac8fecf8 1235 if( ( ret = mgf_mask( buf + 1, hlen, buf + hlen + 1, ilen - hlen - 1,
valeyev 0:e056ac8fecf8 1236 &md_ctx ) ) != 0 ||
valeyev 0:e056ac8fecf8 1237 /* DB: Apply dbMask to maskedDB */
valeyev 0:e056ac8fecf8 1238 ( ret = mgf_mask( buf + hlen + 1, ilen - hlen - 1, buf + 1, hlen,
valeyev 0:e056ac8fecf8 1239 &md_ctx ) ) != 0 )
valeyev 0:e056ac8fecf8 1240 {
valeyev 0:e056ac8fecf8 1241 mbedtls_md_free( &md_ctx );
valeyev 0:e056ac8fecf8 1242 goto cleanup;
valeyev 0:e056ac8fecf8 1243 }
valeyev 0:e056ac8fecf8 1244
valeyev 0:e056ac8fecf8 1245 mbedtls_md_free( &md_ctx );
valeyev 0:e056ac8fecf8 1246
valeyev 0:e056ac8fecf8 1247 /* Generate lHash */
valeyev 0:e056ac8fecf8 1248 if( ( ret = mbedtls_md( md_info, label, label_len, lhash ) ) != 0 )
valeyev 0:e056ac8fecf8 1249 goto cleanup;
valeyev 0:e056ac8fecf8 1250
valeyev 0:e056ac8fecf8 1251 /*
valeyev 0:e056ac8fecf8 1252 * Check contents, in "constant-time"
valeyev 0:e056ac8fecf8 1253 */
valeyev 0:e056ac8fecf8 1254 p = buf;
valeyev 0:e056ac8fecf8 1255 bad = 0;
valeyev 0:e056ac8fecf8 1256
valeyev 0:e056ac8fecf8 1257 bad |= *p++; /* First byte must be 0 */
valeyev 0:e056ac8fecf8 1258
valeyev 0:e056ac8fecf8 1259 p += hlen; /* Skip seed */
valeyev 0:e056ac8fecf8 1260
valeyev 0:e056ac8fecf8 1261 /* Check lHash */
valeyev 0:e056ac8fecf8 1262 for( i = 0; i < hlen; i++ )
valeyev 0:e056ac8fecf8 1263 bad |= lhash[i] ^ *p++;
valeyev 0:e056ac8fecf8 1264
valeyev 0:e056ac8fecf8 1265 /* Get zero-padding len, but always read till end of buffer
valeyev 0:e056ac8fecf8 1266 * (minus one, for the 01 byte) */
valeyev 0:e056ac8fecf8 1267 pad_len = 0;
valeyev 0:e056ac8fecf8 1268 pad_done = 0;
valeyev 0:e056ac8fecf8 1269 for( i = 0; i < ilen - 2 * hlen - 2; i++ )
valeyev 0:e056ac8fecf8 1270 {
valeyev 0:e056ac8fecf8 1271 pad_done |= p[i];
valeyev 0:e056ac8fecf8 1272 pad_len += ((pad_done | (unsigned char)-pad_done) >> 7) ^ 1;
valeyev 0:e056ac8fecf8 1273 }
valeyev 0:e056ac8fecf8 1274
valeyev 0:e056ac8fecf8 1275 p += pad_len;
valeyev 0:e056ac8fecf8 1276 bad |= *p++ ^ 0x01;
valeyev 0:e056ac8fecf8 1277
valeyev 0:e056ac8fecf8 1278 /*
valeyev 0:e056ac8fecf8 1279 * The only information "leaked" is whether the padding was correct or not
valeyev 0:e056ac8fecf8 1280 * (eg, no data is copied if it was not correct). This meets the
valeyev 0:e056ac8fecf8 1281 * recommendations in PKCS#1 v2.2: an opponent cannot distinguish between
valeyev 0:e056ac8fecf8 1282 * the different error conditions.
valeyev 0:e056ac8fecf8 1283 */
valeyev 0:e056ac8fecf8 1284 if( bad != 0 )
valeyev 0:e056ac8fecf8 1285 {
valeyev 0:e056ac8fecf8 1286 ret = MBEDTLS_ERR_RSA_INVALID_PADDING;
valeyev 0:e056ac8fecf8 1287 goto cleanup;
valeyev 0:e056ac8fecf8 1288 }
valeyev 0:e056ac8fecf8 1289
valeyev 0:e056ac8fecf8 1290 if( ilen - ( p - buf ) > output_max_len )
valeyev 0:e056ac8fecf8 1291 {
valeyev 0:e056ac8fecf8 1292 ret = MBEDTLS_ERR_RSA_OUTPUT_TOO_LARGE;
valeyev 0:e056ac8fecf8 1293 goto cleanup;
valeyev 0:e056ac8fecf8 1294 }
valeyev 0:e056ac8fecf8 1295
valeyev 0:e056ac8fecf8 1296 *olen = ilen - (p - buf);
valeyev 0:e056ac8fecf8 1297 memcpy( output, p, *olen );
valeyev 0:e056ac8fecf8 1298 ret = 0;
valeyev 0:e056ac8fecf8 1299
valeyev 0:e056ac8fecf8 1300 cleanup:
valeyev 0:e056ac8fecf8 1301 mbedtls_zeroize( buf, sizeof( buf ) );
valeyev 0:e056ac8fecf8 1302 mbedtls_zeroize( lhash, sizeof( lhash ) );
valeyev 0:e056ac8fecf8 1303
valeyev 0:e056ac8fecf8 1304 return( ret );
valeyev 0:e056ac8fecf8 1305 }
valeyev 0:e056ac8fecf8 1306 #endif /* MBEDTLS_PKCS1_V21 */
valeyev 0:e056ac8fecf8 1307
valeyev 0:e056ac8fecf8 1308 #if defined(MBEDTLS_PKCS1_V15)
valeyev 0:e056ac8fecf8 1309 /*
valeyev 0:e056ac8fecf8 1310 * Implementation of the PKCS#1 v2.1 RSAES-PKCS1-V1_5-DECRYPT function
valeyev 0:e056ac8fecf8 1311 */
valeyev 0:e056ac8fecf8 1312 int mbedtls_rsa_rsaes_pkcs1_v15_decrypt( mbedtls_rsa_context *ctx,
valeyev 0:e056ac8fecf8 1313 int (*f_rng)(void *, unsigned char *, size_t),
valeyev 0:e056ac8fecf8 1314 void *p_rng,
valeyev 0:e056ac8fecf8 1315 int mode, size_t *olen,
valeyev 0:e056ac8fecf8 1316 const unsigned char *input,
valeyev 0:e056ac8fecf8 1317 unsigned char *output,
valeyev 0:e056ac8fecf8 1318 size_t output_max_len)
valeyev 0:e056ac8fecf8 1319 {
valeyev 0:e056ac8fecf8 1320 int ret;
valeyev 0:e056ac8fecf8 1321 size_t ilen, pad_count = 0, i;
valeyev 0:e056ac8fecf8 1322 unsigned char *p, bad, pad_done = 0;
valeyev 0:e056ac8fecf8 1323 unsigned char buf[MBEDTLS_MPI_MAX_SIZE];
valeyev 0:e056ac8fecf8 1324
valeyev 0:e056ac8fecf8 1325 if( mode == MBEDTLS_RSA_PRIVATE && ctx->padding != MBEDTLS_RSA_PKCS_V15 )
valeyev 0:e056ac8fecf8 1326 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 1327
valeyev 0:e056ac8fecf8 1328 ilen = ctx->len;
valeyev 0:e056ac8fecf8 1329
valeyev 0:e056ac8fecf8 1330 if( ilen < 16 || ilen > sizeof( buf ) )
valeyev 0:e056ac8fecf8 1331 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 1332
valeyev 0:e056ac8fecf8 1333 ret = ( mode == MBEDTLS_RSA_PUBLIC )
valeyev 0:e056ac8fecf8 1334 ? mbedtls_rsa_public( ctx, input, buf )
valeyev 0:e056ac8fecf8 1335 : mbedtls_rsa_private( ctx, f_rng, p_rng, input, buf );
valeyev 0:e056ac8fecf8 1336
valeyev 0:e056ac8fecf8 1337 if( ret != 0 )
valeyev 0:e056ac8fecf8 1338 goto cleanup;
valeyev 0:e056ac8fecf8 1339
valeyev 0:e056ac8fecf8 1340 p = buf;
valeyev 0:e056ac8fecf8 1341 bad = 0;
valeyev 0:e056ac8fecf8 1342
valeyev 0:e056ac8fecf8 1343 /*
valeyev 0:e056ac8fecf8 1344 * Check and get padding len in "constant-time"
valeyev 0:e056ac8fecf8 1345 */
valeyev 0:e056ac8fecf8 1346 bad |= *p++; /* First byte must be 0 */
valeyev 0:e056ac8fecf8 1347
valeyev 0:e056ac8fecf8 1348 /* This test does not depend on secret data */
valeyev 0:e056ac8fecf8 1349 if( mode == MBEDTLS_RSA_PRIVATE )
valeyev 0:e056ac8fecf8 1350 {
valeyev 0:e056ac8fecf8 1351 bad |= *p++ ^ MBEDTLS_RSA_CRYPT;
valeyev 0:e056ac8fecf8 1352
valeyev 0:e056ac8fecf8 1353 /* Get padding len, but always read till end of buffer
valeyev 0:e056ac8fecf8 1354 * (minus one, for the 00 byte) */
valeyev 0:e056ac8fecf8 1355 for( i = 0; i < ilen - 3; i++ )
valeyev 0:e056ac8fecf8 1356 {
valeyev 0:e056ac8fecf8 1357 pad_done |= ((p[i] | (unsigned char)-p[i]) >> 7) ^ 1;
valeyev 0:e056ac8fecf8 1358 pad_count += ((pad_done | (unsigned char)-pad_done) >> 7) ^ 1;
valeyev 0:e056ac8fecf8 1359 }
valeyev 0:e056ac8fecf8 1360
valeyev 0:e056ac8fecf8 1361 p += pad_count;
valeyev 0:e056ac8fecf8 1362 bad |= *p++; /* Must be zero */
valeyev 0:e056ac8fecf8 1363 }
valeyev 0:e056ac8fecf8 1364 else
valeyev 0:e056ac8fecf8 1365 {
valeyev 0:e056ac8fecf8 1366 bad |= *p++ ^ MBEDTLS_RSA_SIGN;
valeyev 0:e056ac8fecf8 1367
valeyev 0:e056ac8fecf8 1368 /* Get padding len, but always read till end of buffer
valeyev 0:e056ac8fecf8 1369 * (minus one, for the 00 byte) */
valeyev 0:e056ac8fecf8 1370 for( i = 0; i < ilen - 3; i++ )
valeyev 0:e056ac8fecf8 1371 {
valeyev 0:e056ac8fecf8 1372 pad_done |= ( p[i] != 0xFF );
valeyev 0:e056ac8fecf8 1373 pad_count += ( pad_done == 0 );
valeyev 0:e056ac8fecf8 1374 }
valeyev 0:e056ac8fecf8 1375
valeyev 0:e056ac8fecf8 1376 p += pad_count;
valeyev 0:e056ac8fecf8 1377 bad |= *p++; /* Must be zero */
valeyev 0:e056ac8fecf8 1378 }
valeyev 0:e056ac8fecf8 1379
valeyev 0:e056ac8fecf8 1380 bad |= ( pad_count < 8 );
valeyev 0:e056ac8fecf8 1381
valeyev 0:e056ac8fecf8 1382 if( bad )
valeyev 0:e056ac8fecf8 1383 {
valeyev 0:e056ac8fecf8 1384 ret = MBEDTLS_ERR_RSA_INVALID_PADDING;
valeyev 0:e056ac8fecf8 1385 goto cleanup;
valeyev 0:e056ac8fecf8 1386 }
valeyev 0:e056ac8fecf8 1387
valeyev 0:e056ac8fecf8 1388 if( ilen - ( p - buf ) > output_max_len )
valeyev 0:e056ac8fecf8 1389 {
valeyev 0:e056ac8fecf8 1390 ret = MBEDTLS_ERR_RSA_OUTPUT_TOO_LARGE;
valeyev 0:e056ac8fecf8 1391 goto cleanup;
valeyev 0:e056ac8fecf8 1392 }
valeyev 0:e056ac8fecf8 1393
valeyev 0:e056ac8fecf8 1394 *olen = ilen - (p - buf);
valeyev 0:e056ac8fecf8 1395 memcpy( output, p, *olen );
valeyev 0:e056ac8fecf8 1396 ret = 0;
valeyev 0:e056ac8fecf8 1397
valeyev 0:e056ac8fecf8 1398 cleanup:
valeyev 0:e056ac8fecf8 1399 mbedtls_zeroize( buf, sizeof( buf ) );
valeyev 0:e056ac8fecf8 1400
valeyev 0:e056ac8fecf8 1401 return( ret );
valeyev 0:e056ac8fecf8 1402 }
valeyev 0:e056ac8fecf8 1403 #endif /* MBEDTLS_PKCS1_V15 */
valeyev 0:e056ac8fecf8 1404
valeyev 0:e056ac8fecf8 1405 /*
valeyev 0:e056ac8fecf8 1406 * Do an RSA operation, then remove the message padding
valeyev 0:e056ac8fecf8 1407 */
valeyev 0:e056ac8fecf8 1408 int mbedtls_rsa_pkcs1_decrypt( mbedtls_rsa_context *ctx,
valeyev 0:e056ac8fecf8 1409 int (*f_rng)(void *, unsigned char *, size_t),
valeyev 0:e056ac8fecf8 1410 void *p_rng,
valeyev 0:e056ac8fecf8 1411 int mode, size_t *olen,
valeyev 0:e056ac8fecf8 1412 const unsigned char *input,
valeyev 0:e056ac8fecf8 1413 unsigned char *output,
valeyev 0:e056ac8fecf8 1414 size_t output_max_len)
valeyev 0:e056ac8fecf8 1415 {
valeyev 0:e056ac8fecf8 1416 switch( ctx->padding )
valeyev 0:e056ac8fecf8 1417 {
valeyev 0:e056ac8fecf8 1418 #if defined(MBEDTLS_PKCS1_V15)
valeyev 0:e056ac8fecf8 1419 case MBEDTLS_RSA_PKCS_V15:
valeyev 0:e056ac8fecf8 1420 return mbedtls_rsa_rsaes_pkcs1_v15_decrypt( ctx, f_rng, p_rng, mode, olen,
valeyev 0:e056ac8fecf8 1421 input, output, output_max_len );
valeyev 0:e056ac8fecf8 1422 #endif
valeyev 0:e056ac8fecf8 1423
valeyev 0:e056ac8fecf8 1424 #if defined(MBEDTLS_PKCS1_V21)
valeyev 0:e056ac8fecf8 1425 case MBEDTLS_RSA_PKCS_V21:
valeyev 0:e056ac8fecf8 1426 return mbedtls_rsa_rsaes_oaep_decrypt( ctx, f_rng, p_rng, mode, NULL, 0,
valeyev 0:e056ac8fecf8 1427 olen, input, output,
valeyev 0:e056ac8fecf8 1428 output_max_len );
valeyev 0:e056ac8fecf8 1429 #endif
valeyev 0:e056ac8fecf8 1430
valeyev 0:e056ac8fecf8 1431 default:
valeyev 0:e056ac8fecf8 1432 return( MBEDTLS_ERR_RSA_INVALID_PADDING );
valeyev 0:e056ac8fecf8 1433 }
valeyev 0:e056ac8fecf8 1434 }
valeyev 0:e056ac8fecf8 1435
valeyev 0:e056ac8fecf8 1436 #if defined(MBEDTLS_PKCS1_V21)
valeyev 0:e056ac8fecf8 1437 /*
valeyev 0:e056ac8fecf8 1438 * Implementation of the PKCS#1 v2.1 RSASSA-PSS-SIGN function
valeyev 0:e056ac8fecf8 1439 */
valeyev 0:e056ac8fecf8 1440 int mbedtls_rsa_rsassa_pss_sign( mbedtls_rsa_context *ctx,
valeyev 0:e056ac8fecf8 1441 int (*f_rng)(void *, unsigned char *, size_t),
valeyev 0:e056ac8fecf8 1442 void *p_rng,
valeyev 0:e056ac8fecf8 1443 int mode,
valeyev 0:e056ac8fecf8 1444 mbedtls_md_type_t md_alg,
valeyev 0:e056ac8fecf8 1445 unsigned int hashlen,
valeyev 0:e056ac8fecf8 1446 const unsigned char *hash,
valeyev 0:e056ac8fecf8 1447 unsigned char *sig )
valeyev 0:e056ac8fecf8 1448 {
valeyev 0:e056ac8fecf8 1449 size_t olen;
valeyev 0:e056ac8fecf8 1450 unsigned char *p = sig;
valeyev 0:e056ac8fecf8 1451 unsigned char salt[MBEDTLS_MD_MAX_SIZE];
valeyev 0:e056ac8fecf8 1452 unsigned int slen, hlen, offset = 0;
valeyev 0:e056ac8fecf8 1453 int ret;
valeyev 0:e056ac8fecf8 1454 size_t msb;
valeyev 0:e056ac8fecf8 1455 const mbedtls_md_info_t *md_info;
valeyev 0:e056ac8fecf8 1456 mbedtls_md_context_t md_ctx;
valeyev 0:e056ac8fecf8 1457
valeyev 0:e056ac8fecf8 1458 if( mode == MBEDTLS_RSA_PRIVATE && ctx->padding != MBEDTLS_RSA_PKCS_V21 )
valeyev 0:e056ac8fecf8 1459 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 1460
valeyev 0:e056ac8fecf8 1461 if( f_rng == NULL )
valeyev 0:e056ac8fecf8 1462 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 1463
valeyev 0:e056ac8fecf8 1464 olen = ctx->len;
valeyev 0:e056ac8fecf8 1465
valeyev 0:e056ac8fecf8 1466 if( md_alg != MBEDTLS_MD_NONE )
valeyev 0:e056ac8fecf8 1467 {
valeyev 0:e056ac8fecf8 1468 /* Gather length of hash to sign */
valeyev 0:e056ac8fecf8 1469 md_info = mbedtls_md_info_from_type( md_alg );
valeyev 0:e056ac8fecf8 1470 if( md_info == NULL )
valeyev 0:e056ac8fecf8 1471 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 1472
valeyev 0:e056ac8fecf8 1473 hashlen = mbedtls_md_get_size( md_info );
valeyev 0:e056ac8fecf8 1474 }
valeyev 0:e056ac8fecf8 1475
valeyev 0:e056ac8fecf8 1476 md_info = mbedtls_md_info_from_type( (mbedtls_md_type_t) ctx->hash_id );
valeyev 0:e056ac8fecf8 1477 if( md_info == NULL )
valeyev 0:e056ac8fecf8 1478 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 1479
valeyev 0:e056ac8fecf8 1480 hlen = mbedtls_md_get_size( md_info );
valeyev 0:e056ac8fecf8 1481 slen = hlen;
valeyev 0:e056ac8fecf8 1482
valeyev 0:e056ac8fecf8 1483 if( olen < hlen + slen + 2 )
valeyev 0:e056ac8fecf8 1484 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 1485
valeyev 0:e056ac8fecf8 1486 memset( sig, 0, olen );
valeyev 0:e056ac8fecf8 1487
valeyev 0:e056ac8fecf8 1488 /* Generate salt of length slen */
valeyev 0:e056ac8fecf8 1489 if( ( ret = f_rng( p_rng, salt, slen ) ) != 0 )
valeyev 0:e056ac8fecf8 1490 return( MBEDTLS_ERR_RSA_RNG_FAILED + ret );
valeyev 0:e056ac8fecf8 1491
valeyev 0:e056ac8fecf8 1492 /* Note: EMSA-PSS encoding is over the length of N - 1 bits */
valeyev 0:e056ac8fecf8 1493 msb = mbedtls_mpi_bitlen( &ctx->N ) - 1;
valeyev 0:e056ac8fecf8 1494 p += olen - hlen * 2 - 2;
valeyev 0:e056ac8fecf8 1495 *p++ = 0x01;
valeyev 0:e056ac8fecf8 1496 memcpy( p, salt, slen );
valeyev 0:e056ac8fecf8 1497 p += slen;
valeyev 0:e056ac8fecf8 1498
valeyev 0:e056ac8fecf8 1499 mbedtls_md_init( &md_ctx );
valeyev 0:e056ac8fecf8 1500 if( ( ret = mbedtls_md_setup( &md_ctx, md_info, 0 ) ) != 0 )
valeyev 0:e056ac8fecf8 1501 goto exit;
valeyev 0:e056ac8fecf8 1502
valeyev 0:e056ac8fecf8 1503 /* Generate H = Hash( M' ) */
valeyev 0:e056ac8fecf8 1504 if( ( ret = mbedtls_md_starts( &md_ctx ) ) != 0 )
valeyev 0:e056ac8fecf8 1505 goto exit;
valeyev 0:e056ac8fecf8 1506 if( ( ret = mbedtls_md_update( &md_ctx, p, 8 ) ) != 0 )
valeyev 0:e056ac8fecf8 1507 goto exit;
valeyev 0:e056ac8fecf8 1508 if( ( ret = mbedtls_md_update( &md_ctx, hash, hashlen ) ) != 0 )
valeyev 0:e056ac8fecf8 1509 goto exit;
valeyev 0:e056ac8fecf8 1510 if( ( ret = mbedtls_md_update( &md_ctx, salt, slen ) ) != 0 )
valeyev 0:e056ac8fecf8 1511 goto exit;
valeyev 0:e056ac8fecf8 1512 if( ( ret = mbedtls_md_finish( &md_ctx, p ) ) != 0 )
valeyev 0:e056ac8fecf8 1513 goto exit;
valeyev 0:e056ac8fecf8 1514
valeyev 0:e056ac8fecf8 1515 /* Compensate for boundary condition when applying mask */
valeyev 0:e056ac8fecf8 1516 if( msb % 8 == 0 )
valeyev 0:e056ac8fecf8 1517 offset = 1;
valeyev 0:e056ac8fecf8 1518
valeyev 0:e056ac8fecf8 1519 /* maskedDB: Apply dbMask to DB */
valeyev 0:e056ac8fecf8 1520 if( ( ret = mgf_mask( sig + offset, olen - hlen - 1 - offset, p, hlen,
valeyev 0:e056ac8fecf8 1521 &md_ctx ) ) != 0 )
valeyev 0:e056ac8fecf8 1522 goto exit;
valeyev 0:e056ac8fecf8 1523
valeyev 0:e056ac8fecf8 1524 msb = mbedtls_mpi_bitlen( &ctx->N ) - 1;
valeyev 0:e056ac8fecf8 1525 sig[0] &= 0xFF >> ( olen * 8 - msb );
valeyev 0:e056ac8fecf8 1526
valeyev 0:e056ac8fecf8 1527 p += hlen;
valeyev 0:e056ac8fecf8 1528 *p++ = 0xBC;
valeyev 0:e056ac8fecf8 1529
valeyev 0:e056ac8fecf8 1530 mbedtls_zeroize( salt, sizeof( salt ) );
valeyev 0:e056ac8fecf8 1531
valeyev 0:e056ac8fecf8 1532 exit:
valeyev 0:e056ac8fecf8 1533 mbedtls_md_free( &md_ctx );
valeyev 0:e056ac8fecf8 1534
valeyev 0:e056ac8fecf8 1535 if( ret != 0 )
valeyev 0:e056ac8fecf8 1536 return( ret );
valeyev 0:e056ac8fecf8 1537
valeyev 0:e056ac8fecf8 1538 return( ( mode == MBEDTLS_RSA_PUBLIC )
valeyev 0:e056ac8fecf8 1539 ? mbedtls_rsa_public( ctx, sig, sig )
valeyev 0:e056ac8fecf8 1540 : mbedtls_rsa_private( ctx, f_rng, p_rng, sig, sig ) );
valeyev 0:e056ac8fecf8 1541 }
valeyev 0:e056ac8fecf8 1542 #endif /* MBEDTLS_PKCS1_V21 */
valeyev 0:e056ac8fecf8 1543
valeyev 0:e056ac8fecf8 1544 #if defined(MBEDTLS_PKCS1_V15)
valeyev 0:e056ac8fecf8 1545 /*
valeyev 0:e056ac8fecf8 1546 * Implementation of the PKCS#1 v2.1 RSASSA-PKCS1-V1_5-SIGN function
valeyev 0:e056ac8fecf8 1547 */
valeyev 0:e056ac8fecf8 1548
valeyev 0:e056ac8fecf8 1549 /* Construct a PKCS v1.5 encoding of a hashed message
valeyev 0:e056ac8fecf8 1550 *
valeyev 0:e056ac8fecf8 1551 * This is used both for signature generation and verification.
valeyev 0:e056ac8fecf8 1552 *
valeyev 0:e056ac8fecf8 1553 * Parameters:
valeyev 0:e056ac8fecf8 1554 * - md_alg: Identifies the hash algorithm used to generate the given hash;
valeyev 0:e056ac8fecf8 1555 * MBEDTLS_MD_NONE if raw data is signed.
valeyev 0:e056ac8fecf8 1556 * - hashlen: Length of hash in case hashlen is MBEDTLS_MD_NONE.
valeyev 0:e056ac8fecf8 1557 * - hash: Buffer containing the hashed message or the raw data.
valeyev 0:e056ac8fecf8 1558 * - dst_len: Length of the encoded message.
valeyev 0:e056ac8fecf8 1559 * - dst: Buffer to hold the encoded message.
valeyev 0:e056ac8fecf8 1560 *
valeyev 0:e056ac8fecf8 1561 * Assumptions:
valeyev 0:e056ac8fecf8 1562 * - hash has size hashlen if md_alg == MBEDTLS_MD_NONE.
valeyev 0:e056ac8fecf8 1563 * - hash has size corresponding to md_alg if md_alg != MBEDTLS_MD_NONE.
valeyev 0:e056ac8fecf8 1564 * - dst points to a buffer of size at least dst_len.
valeyev 0:e056ac8fecf8 1565 *
valeyev 0:e056ac8fecf8 1566 */
valeyev 0:e056ac8fecf8 1567 static int rsa_rsassa_pkcs1_v15_encode( mbedtls_md_type_t md_alg,
valeyev 0:e056ac8fecf8 1568 unsigned int hashlen,
valeyev 0:e056ac8fecf8 1569 const unsigned char *hash,
valeyev 0:e056ac8fecf8 1570 size_t dst_len,
valeyev 0:e056ac8fecf8 1571 unsigned char *dst )
valeyev 0:e056ac8fecf8 1572 {
valeyev 0:e056ac8fecf8 1573 size_t oid_size = 0;
valeyev 0:e056ac8fecf8 1574 size_t nb_pad = dst_len;
valeyev 0:e056ac8fecf8 1575 unsigned char *p = dst;
valeyev 0:e056ac8fecf8 1576 const char *oid = NULL;
valeyev 0:e056ac8fecf8 1577
valeyev 0:e056ac8fecf8 1578 /* Are we signing hashed or raw data? */
valeyev 0:e056ac8fecf8 1579 if( md_alg != MBEDTLS_MD_NONE )
valeyev 0:e056ac8fecf8 1580 {
valeyev 0:e056ac8fecf8 1581 const mbedtls_md_info_t *md_info = mbedtls_md_info_from_type( md_alg );
valeyev 0:e056ac8fecf8 1582 if( md_info == NULL )
valeyev 0:e056ac8fecf8 1583 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 1584
valeyev 0:e056ac8fecf8 1585 if( mbedtls_oid_get_oid_by_md( md_alg, &oid, &oid_size ) != 0 )
valeyev 0:e056ac8fecf8 1586 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 1587
valeyev 0:e056ac8fecf8 1588 hashlen = mbedtls_md_get_size( md_info );
valeyev 0:e056ac8fecf8 1589
valeyev 0:e056ac8fecf8 1590 /* Double-check that 8 + hashlen + oid_size can be used as a
valeyev 0:e056ac8fecf8 1591 * 1-byte ASN.1 length encoding and that there's no overflow. */
valeyev 0:e056ac8fecf8 1592 if( 8 + hashlen + oid_size >= 0x80 ||
valeyev 0:e056ac8fecf8 1593 10 + hashlen < hashlen ||
valeyev 0:e056ac8fecf8 1594 10 + hashlen + oid_size < 10 + hashlen )
valeyev 0:e056ac8fecf8 1595 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 1596
valeyev 0:e056ac8fecf8 1597 /*
valeyev 0:e056ac8fecf8 1598 * Static bounds check:
valeyev 0:e056ac8fecf8 1599 * - Need 10 bytes for five tag-length pairs.
valeyev 0:e056ac8fecf8 1600 * (Insist on 1-byte length encodings to protect against variants of
valeyev 0:e056ac8fecf8 1601 * Bleichenbacher's forgery attack against lax PKCS#1v1.5 verification)
valeyev 0:e056ac8fecf8 1602 * - Need hashlen bytes for hash
valeyev 0:e056ac8fecf8 1603 * - Need oid_size bytes for hash alg OID.
valeyev 0:e056ac8fecf8 1604 */
valeyev 0:e056ac8fecf8 1605 if( nb_pad < 10 + hashlen + oid_size )
valeyev 0:e056ac8fecf8 1606 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 1607 nb_pad -= 10 + hashlen + oid_size;
valeyev 0:e056ac8fecf8 1608 }
valeyev 0:e056ac8fecf8 1609 else
valeyev 0:e056ac8fecf8 1610 {
valeyev 0:e056ac8fecf8 1611 if( nb_pad < hashlen )
valeyev 0:e056ac8fecf8 1612 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 1613
valeyev 0:e056ac8fecf8 1614 nb_pad -= hashlen;
valeyev 0:e056ac8fecf8 1615 }
valeyev 0:e056ac8fecf8 1616
valeyev 0:e056ac8fecf8 1617 /* Need space for signature header and padding delimiter (3 bytes),
valeyev 0:e056ac8fecf8 1618 * and 8 bytes for the minimal padding */
valeyev 0:e056ac8fecf8 1619 if( nb_pad < 3 + 8 )
valeyev 0:e056ac8fecf8 1620 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 1621 nb_pad -= 3;
valeyev 0:e056ac8fecf8 1622
valeyev 0:e056ac8fecf8 1623 /* Now nb_pad is the amount of memory to be filled
valeyev 0:e056ac8fecf8 1624 * with padding, and at least 8 bytes long. */
valeyev 0:e056ac8fecf8 1625
valeyev 0:e056ac8fecf8 1626 /* Write signature header and padding */
valeyev 0:e056ac8fecf8 1627 *p++ = 0;
valeyev 0:e056ac8fecf8 1628 *p++ = MBEDTLS_RSA_SIGN;
valeyev 0:e056ac8fecf8 1629 memset( p, 0xFF, nb_pad );
valeyev 0:e056ac8fecf8 1630 p += nb_pad;
valeyev 0:e056ac8fecf8 1631 *p++ = 0;
valeyev 0:e056ac8fecf8 1632
valeyev 0:e056ac8fecf8 1633 /* Are we signing raw data? */
valeyev 0:e056ac8fecf8 1634 if( md_alg == MBEDTLS_MD_NONE )
valeyev 0:e056ac8fecf8 1635 {
valeyev 0:e056ac8fecf8 1636 memcpy( p, hash, hashlen );
valeyev 0:e056ac8fecf8 1637 return( 0 );
valeyev 0:e056ac8fecf8 1638 }
valeyev 0:e056ac8fecf8 1639
valeyev 0:e056ac8fecf8 1640 /* Signing hashed data, add corresponding ASN.1 structure
valeyev 0:e056ac8fecf8 1641 *
valeyev 0:e056ac8fecf8 1642 * DigestInfo ::= SEQUENCE {
valeyev 0:e056ac8fecf8 1643 * digestAlgorithm DigestAlgorithmIdentifier,
valeyev 0:e056ac8fecf8 1644 * digest Digest }
valeyev 0:e056ac8fecf8 1645 * DigestAlgorithmIdentifier ::= AlgorithmIdentifier
valeyev 0:e056ac8fecf8 1646 * Digest ::= OCTET STRING
valeyev 0:e056ac8fecf8 1647 *
valeyev 0:e056ac8fecf8 1648 * Schematic:
valeyev 0:e056ac8fecf8 1649 * TAG-SEQ + LEN [ TAG-SEQ + LEN [ TAG-OID + LEN [ OID ]
valeyev 0:e056ac8fecf8 1650 * TAG-NULL + LEN [ NULL ] ]
valeyev 0:e056ac8fecf8 1651 * TAG-OCTET + LEN [ HASH ] ]
valeyev 0:e056ac8fecf8 1652 */
valeyev 0:e056ac8fecf8 1653 *p++ = MBEDTLS_ASN1_SEQUENCE | MBEDTLS_ASN1_CONSTRUCTED;
valeyev 0:e056ac8fecf8 1654 *p++ = (unsigned char)( 0x08 + oid_size + hashlen );
valeyev 0:e056ac8fecf8 1655 *p++ = MBEDTLS_ASN1_SEQUENCE | MBEDTLS_ASN1_CONSTRUCTED;
valeyev 0:e056ac8fecf8 1656 *p++ = (unsigned char)( 0x04 + oid_size );
valeyev 0:e056ac8fecf8 1657 *p++ = MBEDTLS_ASN1_OID;
valeyev 0:e056ac8fecf8 1658 *p++ = (unsigned char) oid_size;
valeyev 0:e056ac8fecf8 1659 memcpy( p, oid, oid_size );
valeyev 0:e056ac8fecf8 1660 p += oid_size;
valeyev 0:e056ac8fecf8 1661 *p++ = MBEDTLS_ASN1_NULL;
valeyev 0:e056ac8fecf8 1662 *p++ = 0x00;
valeyev 0:e056ac8fecf8 1663 *p++ = MBEDTLS_ASN1_OCTET_STRING;
valeyev 0:e056ac8fecf8 1664 *p++ = (unsigned char) hashlen;
valeyev 0:e056ac8fecf8 1665 memcpy( p, hash, hashlen );
valeyev 0:e056ac8fecf8 1666 p += hashlen;
valeyev 0:e056ac8fecf8 1667
valeyev 0:e056ac8fecf8 1668 /* Just a sanity-check, should be automatic
valeyev 0:e056ac8fecf8 1669 * after the initial bounds check. */
valeyev 0:e056ac8fecf8 1670 if( p != dst + dst_len )
valeyev 0:e056ac8fecf8 1671 {
valeyev 0:e056ac8fecf8 1672 mbedtls_zeroize( dst, dst_len );
valeyev 0:e056ac8fecf8 1673 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 1674 }
valeyev 0:e056ac8fecf8 1675
valeyev 0:e056ac8fecf8 1676 return( 0 );
valeyev 0:e056ac8fecf8 1677 }
valeyev 0:e056ac8fecf8 1678
valeyev 0:e056ac8fecf8 1679 /*
valeyev 0:e056ac8fecf8 1680 * Do an RSA operation to sign the message digest
valeyev 0:e056ac8fecf8 1681 */
valeyev 0:e056ac8fecf8 1682 int mbedtls_rsa_rsassa_pkcs1_v15_sign( mbedtls_rsa_context *ctx,
valeyev 0:e056ac8fecf8 1683 int (*f_rng)(void *, unsigned char *, size_t),
valeyev 0:e056ac8fecf8 1684 void *p_rng,
valeyev 0:e056ac8fecf8 1685 int mode,
valeyev 0:e056ac8fecf8 1686 mbedtls_md_type_t md_alg,
valeyev 0:e056ac8fecf8 1687 unsigned int hashlen,
valeyev 0:e056ac8fecf8 1688 const unsigned char *hash,
valeyev 0:e056ac8fecf8 1689 unsigned char *sig )
valeyev 0:e056ac8fecf8 1690 {
valeyev 0:e056ac8fecf8 1691 int ret;
valeyev 0:e056ac8fecf8 1692 unsigned char *sig_try = NULL, *verif = NULL;
valeyev 0:e056ac8fecf8 1693
valeyev 0:e056ac8fecf8 1694 if( mode == MBEDTLS_RSA_PRIVATE && ctx->padding != MBEDTLS_RSA_PKCS_V15 )
valeyev 0:e056ac8fecf8 1695 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 1696
valeyev 0:e056ac8fecf8 1697 /*
valeyev 0:e056ac8fecf8 1698 * Prepare PKCS1-v1.5 encoding (padding and hash identifier)
valeyev 0:e056ac8fecf8 1699 */
valeyev 0:e056ac8fecf8 1700
valeyev 0:e056ac8fecf8 1701 if( ( ret = rsa_rsassa_pkcs1_v15_encode( md_alg, hashlen, hash,
valeyev 0:e056ac8fecf8 1702 ctx->len, sig ) ) != 0 )
valeyev 0:e056ac8fecf8 1703 return( ret );
valeyev 0:e056ac8fecf8 1704
valeyev 0:e056ac8fecf8 1705 /*
valeyev 0:e056ac8fecf8 1706 * Call respective RSA primitive
valeyev 0:e056ac8fecf8 1707 */
valeyev 0:e056ac8fecf8 1708
valeyev 0:e056ac8fecf8 1709 if( mode == MBEDTLS_RSA_PUBLIC )
valeyev 0:e056ac8fecf8 1710 {
valeyev 0:e056ac8fecf8 1711 /* Skip verification on a public key operation */
valeyev 0:e056ac8fecf8 1712 return( mbedtls_rsa_public( ctx, sig, sig ) );
valeyev 0:e056ac8fecf8 1713 }
valeyev 0:e056ac8fecf8 1714
valeyev 0:e056ac8fecf8 1715 /* Private key operation
valeyev 0:e056ac8fecf8 1716 *
valeyev 0:e056ac8fecf8 1717 * In order to prevent Lenstra's attack, make the signature in a
valeyev 0:e056ac8fecf8 1718 * temporary buffer and check it before returning it.
valeyev 0:e056ac8fecf8 1719 */
valeyev 0:e056ac8fecf8 1720
valeyev 0:e056ac8fecf8 1721 sig_try = mbedtls_calloc( 1, ctx->len );
valeyev 0:e056ac8fecf8 1722 if( sig_try == NULL )
valeyev 0:e056ac8fecf8 1723 return( MBEDTLS_ERR_MPI_ALLOC_FAILED );
valeyev 0:e056ac8fecf8 1724
valeyev 0:e056ac8fecf8 1725 verif = mbedtls_calloc( 1, ctx->len );
valeyev 0:e056ac8fecf8 1726 if( verif == NULL )
valeyev 0:e056ac8fecf8 1727 {
valeyev 0:e056ac8fecf8 1728 mbedtls_free( sig_try );
valeyev 0:e056ac8fecf8 1729 return( MBEDTLS_ERR_MPI_ALLOC_FAILED );
valeyev 0:e056ac8fecf8 1730 }
valeyev 0:e056ac8fecf8 1731
valeyev 0:e056ac8fecf8 1732 MBEDTLS_MPI_CHK( mbedtls_rsa_private( ctx, f_rng, p_rng, sig, sig_try ) );
valeyev 0:e056ac8fecf8 1733 MBEDTLS_MPI_CHK( mbedtls_rsa_public( ctx, sig_try, verif ) );
valeyev 0:e056ac8fecf8 1734
valeyev 0:e056ac8fecf8 1735 if( mbedtls_safer_memcmp( verif, sig, ctx->len ) != 0 )
valeyev 0:e056ac8fecf8 1736 {
valeyev 0:e056ac8fecf8 1737 ret = MBEDTLS_ERR_RSA_PRIVATE_FAILED;
valeyev 0:e056ac8fecf8 1738 goto cleanup;
valeyev 0:e056ac8fecf8 1739 }
valeyev 0:e056ac8fecf8 1740
valeyev 0:e056ac8fecf8 1741 memcpy( sig, sig_try, ctx->len );
valeyev 0:e056ac8fecf8 1742
valeyev 0:e056ac8fecf8 1743 cleanup:
valeyev 0:e056ac8fecf8 1744 mbedtls_free( sig_try );
valeyev 0:e056ac8fecf8 1745 mbedtls_free( verif );
valeyev 0:e056ac8fecf8 1746
valeyev 0:e056ac8fecf8 1747 return( ret );
valeyev 0:e056ac8fecf8 1748 }
valeyev 0:e056ac8fecf8 1749 #endif /* MBEDTLS_PKCS1_V15 */
valeyev 0:e056ac8fecf8 1750
valeyev 0:e056ac8fecf8 1751 /*
valeyev 0:e056ac8fecf8 1752 * Do an RSA operation to sign the message digest
valeyev 0:e056ac8fecf8 1753 */
valeyev 0:e056ac8fecf8 1754 int mbedtls_rsa_pkcs1_sign( mbedtls_rsa_context *ctx,
valeyev 0:e056ac8fecf8 1755 int (*f_rng)(void *, unsigned char *, size_t),
valeyev 0:e056ac8fecf8 1756 void *p_rng,
valeyev 0:e056ac8fecf8 1757 int mode,
valeyev 0:e056ac8fecf8 1758 mbedtls_md_type_t md_alg,
valeyev 0:e056ac8fecf8 1759 unsigned int hashlen,
valeyev 0:e056ac8fecf8 1760 const unsigned char *hash,
valeyev 0:e056ac8fecf8 1761 unsigned char *sig )
valeyev 0:e056ac8fecf8 1762 {
valeyev 0:e056ac8fecf8 1763 switch( ctx->padding )
valeyev 0:e056ac8fecf8 1764 {
valeyev 0:e056ac8fecf8 1765 #if defined(MBEDTLS_PKCS1_V15)
valeyev 0:e056ac8fecf8 1766 case MBEDTLS_RSA_PKCS_V15:
valeyev 0:e056ac8fecf8 1767 return mbedtls_rsa_rsassa_pkcs1_v15_sign( ctx, f_rng, p_rng, mode, md_alg,
valeyev 0:e056ac8fecf8 1768 hashlen, hash, sig );
valeyev 0:e056ac8fecf8 1769 #endif
valeyev 0:e056ac8fecf8 1770
valeyev 0:e056ac8fecf8 1771 #if defined(MBEDTLS_PKCS1_V21)
valeyev 0:e056ac8fecf8 1772 case MBEDTLS_RSA_PKCS_V21:
valeyev 0:e056ac8fecf8 1773 return mbedtls_rsa_rsassa_pss_sign( ctx, f_rng, p_rng, mode, md_alg,
valeyev 0:e056ac8fecf8 1774 hashlen, hash, sig );
valeyev 0:e056ac8fecf8 1775 #endif
valeyev 0:e056ac8fecf8 1776
valeyev 0:e056ac8fecf8 1777 default:
valeyev 0:e056ac8fecf8 1778 return( MBEDTLS_ERR_RSA_INVALID_PADDING );
valeyev 0:e056ac8fecf8 1779 }
valeyev 0:e056ac8fecf8 1780 }
valeyev 0:e056ac8fecf8 1781
valeyev 0:e056ac8fecf8 1782 #if defined(MBEDTLS_PKCS1_V21)
valeyev 0:e056ac8fecf8 1783 /*
valeyev 0:e056ac8fecf8 1784 * Implementation of the PKCS#1 v2.1 RSASSA-PSS-VERIFY function
valeyev 0:e056ac8fecf8 1785 */
valeyev 0:e056ac8fecf8 1786 int mbedtls_rsa_rsassa_pss_verify_ext( mbedtls_rsa_context *ctx,
valeyev 0:e056ac8fecf8 1787 int (*f_rng)(void *, unsigned char *, size_t),
valeyev 0:e056ac8fecf8 1788 void *p_rng,
valeyev 0:e056ac8fecf8 1789 int mode,
valeyev 0:e056ac8fecf8 1790 mbedtls_md_type_t md_alg,
valeyev 0:e056ac8fecf8 1791 unsigned int hashlen,
valeyev 0:e056ac8fecf8 1792 const unsigned char *hash,
valeyev 0:e056ac8fecf8 1793 mbedtls_md_type_t mgf1_hash_id,
valeyev 0:e056ac8fecf8 1794 int expected_salt_len,
valeyev 0:e056ac8fecf8 1795 const unsigned char *sig )
valeyev 0:e056ac8fecf8 1796 {
valeyev 0:e056ac8fecf8 1797 int ret;
valeyev 0:e056ac8fecf8 1798 size_t siglen;
valeyev 0:e056ac8fecf8 1799 unsigned char *p;
valeyev 0:e056ac8fecf8 1800 unsigned char *hash_start;
valeyev 0:e056ac8fecf8 1801 unsigned char result[MBEDTLS_MD_MAX_SIZE];
valeyev 0:e056ac8fecf8 1802 unsigned char zeros[8];
valeyev 0:e056ac8fecf8 1803 unsigned int hlen;
valeyev 0:e056ac8fecf8 1804 size_t observed_salt_len, msb;
valeyev 0:e056ac8fecf8 1805 const mbedtls_md_info_t *md_info;
valeyev 0:e056ac8fecf8 1806 mbedtls_md_context_t md_ctx;
valeyev 0:e056ac8fecf8 1807 unsigned char buf[MBEDTLS_MPI_MAX_SIZE];
valeyev 0:e056ac8fecf8 1808
valeyev 0:e056ac8fecf8 1809 if( mode == MBEDTLS_RSA_PRIVATE && ctx->padding != MBEDTLS_RSA_PKCS_V21 )
valeyev 0:e056ac8fecf8 1810 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 1811
valeyev 0:e056ac8fecf8 1812 siglen = ctx->len;
valeyev 0:e056ac8fecf8 1813
valeyev 0:e056ac8fecf8 1814 if( siglen < 16 || siglen > sizeof( buf ) )
valeyev 0:e056ac8fecf8 1815 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 1816
valeyev 0:e056ac8fecf8 1817 ret = ( mode == MBEDTLS_RSA_PUBLIC )
valeyev 0:e056ac8fecf8 1818 ? mbedtls_rsa_public( ctx, sig, buf )
valeyev 0:e056ac8fecf8 1819 : mbedtls_rsa_private( ctx, f_rng, p_rng, sig, buf );
valeyev 0:e056ac8fecf8 1820
valeyev 0:e056ac8fecf8 1821 if( ret != 0 )
valeyev 0:e056ac8fecf8 1822 return( ret );
valeyev 0:e056ac8fecf8 1823
valeyev 0:e056ac8fecf8 1824 p = buf;
valeyev 0:e056ac8fecf8 1825
valeyev 0:e056ac8fecf8 1826 if( buf[siglen - 1] != 0xBC )
valeyev 0:e056ac8fecf8 1827 return( MBEDTLS_ERR_RSA_INVALID_PADDING );
valeyev 0:e056ac8fecf8 1828
valeyev 0:e056ac8fecf8 1829 if( md_alg != MBEDTLS_MD_NONE )
valeyev 0:e056ac8fecf8 1830 {
valeyev 0:e056ac8fecf8 1831 /* Gather length of hash to sign */
valeyev 0:e056ac8fecf8 1832 md_info = mbedtls_md_info_from_type( md_alg );
valeyev 0:e056ac8fecf8 1833 if( md_info == NULL )
valeyev 0:e056ac8fecf8 1834 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 1835
valeyev 0:e056ac8fecf8 1836 hashlen = mbedtls_md_get_size( md_info );
valeyev 0:e056ac8fecf8 1837 }
valeyev 0:e056ac8fecf8 1838
valeyev 0:e056ac8fecf8 1839 md_info = mbedtls_md_info_from_type( mgf1_hash_id );
valeyev 0:e056ac8fecf8 1840 if( md_info == NULL )
valeyev 0:e056ac8fecf8 1841 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 1842
valeyev 0:e056ac8fecf8 1843 hlen = mbedtls_md_get_size( md_info );
valeyev 0:e056ac8fecf8 1844
valeyev 0:e056ac8fecf8 1845 memset( zeros, 0, 8 );
valeyev 0:e056ac8fecf8 1846
valeyev 0:e056ac8fecf8 1847 /*
valeyev 0:e056ac8fecf8 1848 * Note: EMSA-PSS verification is over the length of N - 1 bits
valeyev 0:e056ac8fecf8 1849 */
valeyev 0:e056ac8fecf8 1850 msb = mbedtls_mpi_bitlen( &ctx->N ) - 1;
valeyev 0:e056ac8fecf8 1851
valeyev 0:e056ac8fecf8 1852 if( buf[0] >> ( 8 - siglen * 8 + msb ) )
valeyev 0:e056ac8fecf8 1853 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 1854
valeyev 0:e056ac8fecf8 1855 /* Compensate for boundary condition when applying mask */
valeyev 0:e056ac8fecf8 1856 if( msb % 8 == 0 )
valeyev 0:e056ac8fecf8 1857 {
valeyev 0:e056ac8fecf8 1858 p++;
valeyev 0:e056ac8fecf8 1859 siglen -= 1;
valeyev 0:e056ac8fecf8 1860 }
valeyev 0:e056ac8fecf8 1861
valeyev 0:e056ac8fecf8 1862 if( siglen < hlen + 2 )
valeyev 0:e056ac8fecf8 1863 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 1864 hash_start = p + siglen - hlen - 1;
valeyev 0:e056ac8fecf8 1865
valeyev 0:e056ac8fecf8 1866 mbedtls_md_init( &md_ctx );
valeyev 0:e056ac8fecf8 1867 if( ( ret = mbedtls_md_setup( &md_ctx, md_info, 0 ) ) != 0 )
valeyev 0:e056ac8fecf8 1868 goto exit;
valeyev 0:e056ac8fecf8 1869
valeyev 0:e056ac8fecf8 1870 ret = mgf_mask( p, siglen - hlen - 1, hash_start, hlen, &md_ctx );
valeyev 0:e056ac8fecf8 1871 if( ret != 0 )
valeyev 0:e056ac8fecf8 1872 goto exit;
valeyev 0:e056ac8fecf8 1873
valeyev 0:e056ac8fecf8 1874 buf[0] &= 0xFF >> ( siglen * 8 - msb );
valeyev 0:e056ac8fecf8 1875
valeyev 0:e056ac8fecf8 1876 while( p < hash_start - 1 && *p == 0 )
valeyev 0:e056ac8fecf8 1877 p++;
valeyev 0:e056ac8fecf8 1878
valeyev 0:e056ac8fecf8 1879 if( *p++ != 0x01 )
valeyev 0:e056ac8fecf8 1880 {
valeyev 0:e056ac8fecf8 1881 ret = MBEDTLS_ERR_RSA_INVALID_PADDING;
valeyev 0:e056ac8fecf8 1882 goto exit;
valeyev 0:e056ac8fecf8 1883 }
valeyev 0:e056ac8fecf8 1884
valeyev 0:e056ac8fecf8 1885 observed_salt_len = hash_start - p;
valeyev 0:e056ac8fecf8 1886
valeyev 0:e056ac8fecf8 1887 if( expected_salt_len != MBEDTLS_RSA_SALT_LEN_ANY &&
valeyev 0:e056ac8fecf8 1888 observed_salt_len != (size_t) expected_salt_len )
valeyev 0:e056ac8fecf8 1889 {
valeyev 0:e056ac8fecf8 1890 ret = MBEDTLS_ERR_RSA_INVALID_PADDING;
valeyev 0:e056ac8fecf8 1891 goto exit;
valeyev 0:e056ac8fecf8 1892 }
valeyev 0:e056ac8fecf8 1893
valeyev 0:e056ac8fecf8 1894 /*
valeyev 0:e056ac8fecf8 1895 * Generate H = Hash( M' )
valeyev 0:e056ac8fecf8 1896 */
valeyev 0:e056ac8fecf8 1897 ret = mbedtls_md_starts( &md_ctx );
valeyev 0:e056ac8fecf8 1898 if ( ret != 0 )
valeyev 0:e056ac8fecf8 1899 goto exit;
valeyev 0:e056ac8fecf8 1900 ret = mbedtls_md_update( &md_ctx, zeros, 8 );
valeyev 0:e056ac8fecf8 1901 if ( ret != 0 )
valeyev 0:e056ac8fecf8 1902 goto exit;
valeyev 0:e056ac8fecf8 1903 ret = mbedtls_md_update( &md_ctx, hash, hashlen );
valeyev 0:e056ac8fecf8 1904 if ( ret != 0 )
valeyev 0:e056ac8fecf8 1905 goto exit;
valeyev 0:e056ac8fecf8 1906 ret = mbedtls_md_update( &md_ctx, p, observed_salt_len );
valeyev 0:e056ac8fecf8 1907 if ( ret != 0 )
valeyev 0:e056ac8fecf8 1908 goto exit;
valeyev 0:e056ac8fecf8 1909 ret = mbedtls_md_finish( &md_ctx, result );
valeyev 0:e056ac8fecf8 1910 if ( ret != 0 )
valeyev 0:e056ac8fecf8 1911 goto exit;
valeyev 0:e056ac8fecf8 1912
valeyev 0:e056ac8fecf8 1913 if( memcmp( hash_start, result, hlen ) != 0 )
valeyev 0:e056ac8fecf8 1914 {
valeyev 0:e056ac8fecf8 1915 ret = MBEDTLS_ERR_RSA_VERIFY_FAILED;
valeyev 0:e056ac8fecf8 1916 goto exit;
valeyev 0:e056ac8fecf8 1917 }
valeyev 0:e056ac8fecf8 1918
valeyev 0:e056ac8fecf8 1919 exit:
valeyev 0:e056ac8fecf8 1920 mbedtls_md_free( &md_ctx );
valeyev 0:e056ac8fecf8 1921
valeyev 0:e056ac8fecf8 1922 return( ret );
valeyev 0:e056ac8fecf8 1923 }
valeyev 0:e056ac8fecf8 1924
valeyev 0:e056ac8fecf8 1925 /*
valeyev 0:e056ac8fecf8 1926 * Simplified PKCS#1 v2.1 RSASSA-PSS-VERIFY function
valeyev 0:e056ac8fecf8 1927 */
valeyev 0:e056ac8fecf8 1928 int mbedtls_rsa_rsassa_pss_verify( mbedtls_rsa_context *ctx,
valeyev 0:e056ac8fecf8 1929 int (*f_rng)(void *, unsigned char *, size_t),
valeyev 0:e056ac8fecf8 1930 void *p_rng,
valeyev 0:e056ac8fecf8 1931 int mode,
valeyev 0:e056ac8fecf8 1932 mbedtls_md_type_t md_alg,
valeyev 0:e056ac8fecf8 1933 unsigned int hashlen,
valeyev 0:e056ac8fecf8 1934 const unsigned char *hash,
valeyev 0:e056ac8fecf8 1935 const unsigned char *sig )
valeyev 0:e056ac8fecf8 1936 {
valeyev 0:e056ac8fecf8 1937 mbedtls_md_type_t mgf1_hash_id = ( ctx->hash_id != MBEDTLS_MD_NONE )
valeyev 0:e056ac8fecf8 1938 ? (mbedtls_md_type_t) ctx->hash_id
valeyev 0:e056ac8fecf8 1939 : md_alg;
valeyev 0:e056ac8fecf8 1940
valeyev 0:e056ac8fecf8 1941 return( mbedtls_rsa_rsassa_pss_verify_ext( ctx, f_rng, p_rng, mode,
valeyev 0:e056ac8fecf8 1942 md_alg, hashlen, hash,
valeyev 0:e056ac8fecf8 1943 mgf1_hash_id, MBEDTLS_RSA_SALT_LEN_ANY,
valeyev 0:e056ac8fecf8 1944 sig ) );
valeyev 0:e056ac8fecf8 1945
valeyev 0:e056ac8fecf8 1946 }
valeyev 0:e056ac8fecf8 1947 #endif /* MBEDTLS_PKCS1_V21 */
valeyev 0:e056ac8fecf8 1948
valeyev 0:e056ac8fecf8 1949 #if defined(MBEDTLS_PKCS1_V15)
valeyev 0:e056ac8fecf8 1950 /*
valeyev 0:e056ac8fecf8 1951 * Implementation of the PKCS#1 v2.1 RSASSA-PKCS1-v1_5-VERIFY function
valeyev 0:e056ac8fecf8 1952 */
valeyev 0:e056ac8fecf8 1953 int mbedtls_rsa_rsassa_pkcs1_v15_verify( mbedtls_rsa_context *ctx,
valeyev 0:e056ac8fecf8 1954 int (*f_rng)(void *, unsigned char *, size_t),
valeyev 0:e056ac8fecf8 1955 void *p_rng,
valeyev 0:e056ac8fecf8 1956 int mode,
valeyev 0:e056ac8fecf8 1957 mbedtls_md_type_t md_alg,
valeyev 0:e056ac8fecf8 1958 unsigned int hashlen,
valeyev 0:e056ac8fecf8 1959 const unsigned char *hash,
valeyev 0:e056ac8fecf8 1960 const unsigned char *sig )
valeyev 0:e056ac8fecf8 1961 {
valeyev 0:e056ac8fecf8 1962 int ret = 0;
valeyev 0:e056ac8fecf8 1963 const size_t sig_len = ctx->len;
valeyev 0:e056ac8fecf8 1964 unsigned char *encoded = NULL, *encoded_expected = NULL;
valeyev 0:e056ac8fecf8 1965
valeyev 0:e056ac8fecf8 1966 if( mode == MBEDTLS_RSA_PRIVATE && ctx->padding != MBEDTLS_RSA_PKCS_V15 )
valeyev 0:e056ac8fecf8 1967 return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
valeyev 0:e056ac8fecf8 1968
valeyev 0:e056ac8fecf8 1969 /*
valeyev 0:e056ac8fecf8 1970 * Prepare expected PKCS1 v1.5 encoding of hash.
valeyev 0:e056ac8fecf8 1971 */
valeyev 0:e056ac8fecf8 1972
valeyev 0:e056ac8fecf8 1973 if( ( encoded = mbedtls_calloc( 1, sig_len ) ) == NULL ||
valeyev 0:e056ac8fecf8 1974 ( encoded_expected = mbedtls_calloc( 1, sig_len ) ) == NULL )
valeyev 0:e056ac8fecf8 1975 {
valeyev 0:e056ac8fecf8 1976 ret = MBEDTLS_ERR_MPI_ALLOC_FAILED;
valeyev 0:e056ac8fecf8 1977 goto cleanup;
valeyev 0:e056ac8fecf8 1978 }
valeyev 0:e056ac8fecf8 1979
valeyev 0:e056ac8fecf8 1980 if( ( ret = rsa_rsassa_pkcs1_v15_encode( md_alg, hashlen, hash, sig_len,
valeyev 0:e056ac8fecf8 1981 encoded_expected ) ) != 0 )
valeyev 0:e056ac8fecf8 1982 goto cleanup;
valeyev 0:e056ac8fecf8 1983
valeyev 0:e056ac8fecf8 1984 /*
valeyev 0:e056ac8fecf8 1985 * Apply RSA primitive to get what should be PKCS1 encoded hash.
valeyev 0:e056ac8fecf8 1986 */
valeyev 0:e056ac8fecf8 1987
valeyev 0:e056ac8fecf8 1988 ret = ( mode == MBEDTLS_RSA_PUBLIC )
valeyev 0:e056ac8fecf8 1989 ? mbedtls_rsa_public( ctx, sig, encoded )
valeyev 0:e056ac8fecf8 1990 : mbedtls_rsa_private( ctx, f_rng, p_rng, sig, encoded );
valeyev 0:e056ac8fecf8 1991 if( ret != 0 )
valeyev 0:e056ac8fecf8 1992 goto cleanup;
valeyev 0:e056ac8fecf8 1993
valeyev 0:e056ac8fecf8 1994 /*
valeyev 0:e056ac8fecf8 1995 * Compare
valeyev 0:e056ac8fecf8 1996 */
valeyev 0:e056ac8fecf8 1997
valeyev 0:e056ac8fecf8 1998 if( ( ret = mbedtls_safer_memcmp( encoded, encoded_expected,
valeyev 0:e056ac8fecf8 1999 sig_len ) ) != 0 )
valeyev 0:e056ac8fecf8 2000 {
valeyev 0:e056ac8fecf8 2001 ret = MBEDTLS_ERR_RSA_VERIFY_FAILED;
valeyev 0:e056ac8fecf8 2002 goto cleanup;
valeyev 0:e056ac8fecf8 2003 }
valeyev 0:e056ac8fecf8 2004
valeyev 0:e056ac8fecf8 2005 cleanup:
valeyev 0:e056ac8fecf8 2006
valeyev 0:e056ac8fecf8 2007 if( encoded != NULL )
valeyev 0:e056ac8fecf8 2008 {
valeyev 0:e056ac8fecf8 2009 mbedtls_zeroize( encoded, sig_len );
valeyev 0:e056ac8fecf8 2010 mbedtls_free( encoded );
valeyev 0:e056ac8fecf8 2011 }
valeyev 0:e056ac8fecf8 2012
valeyev 0:e056ac8fecf8 2013 if( encoded_expected != NULL )
valeyev 0:e056ac8fecf8 2014 {
valeyev 0:e056ac8fecf8 2015 mbedtls_zeroize( encoded_expected, sig_len );
valeyev 0:e056ac8fecf8 2016 mbedtls_free( encoded_expected );
valeyev 0:e056ac8fecf8 2017 }
valeyev 0:e056ac8fecf8 2018
valeyev 0:e056ac8fecf8 2019 return( ret );
valeyev 0:e056ac8fecf8 2020 }
valeyev 0:e056ac8fecf8 2021 #endif /* MBEDTLS_PKCS1_V15 */
valeyev 0:e056ac8fecf8 2022
valeyev 0:e056ac8fecf8 2023 /*
valeyev 0:e056ac8fecf8 2024 * Do an RSA operation and check the message digest
valeyev 0:e056ac8fecf8 2025 */
valeyev 0:e056ac8fecf8 2026 int mbedtls_rsa_pkcs1_verify( mbedtls_rsa_context *ctx,
valeyev 0:e056ac8fecf8 2027 int (*f_rng)(void *, unsigned char *, size_t),
valeyev 0:e056ac8fecf8 2028 void *p_rng,
valeyev 0:e056ac8fecf8 2029 int mode,
valeyev 0:e056ac8fecf8 2030 mbedtls_md_type_t md_alg,
valeyev 0:e056ac8fecf8 2031 unsigned int hashlen,
valeyev 0:e056ac8fecf8 2032 const unsigned char *hash,
valeyev 0:e056ac8fecf8 2033 const unsigned char *sig )
valeyev 0:e056ac8fecf8 2034 {
valeyev 0:e056ac8fecf8 2035 switch( ctx->padding )
valeyev 0:e056ac8fecf8 2036 {
valeyev 0:e056ac8fecf8 2037 #if defined(MBEDTLS_PKCS1_V15)
valeyev 0:e056ac8fecf8 2038 case MBEDTLS_RSA_PKCS_V15:
valeyev 0:e056ac8fecf8 2039 return mbedtls_rsa_rsassa_pkcs1_v15_verify( ctx, f_rng, p_rng, mode, md_alg,
valeyev 0:e056ac8fecf8 2040 hashlen, hash, sig );
valeyev 0:e056ac8fecf8 2041 #endif
valeyev 0:e056ac8fecf8 2042
valeyev 0:e056ac8fecf8 2043 #if defined(MBEDTLS_PKCS1_V21)
valeyev 0:e056ac8fecf8 2044 case MBEDTLS_RSA_PKCS_V21:
valeyev 0:e056ac8fecf8 2045 return mbedtls_rsa_rsassa_pss_verify( ctx, f_rng, p_rng, mode, md_alg,
valeyev 0:e056ac8fecf8 2046 hashlen, hash, sig );
valeyev 0:e056ac8fecf8 2047 #endif
valeyev 0:e056ac8fecf8 2048
valeyev 0:e056ac8fecf8 2049 default:
valeyev 0:e056ac8fecf8 2050 return( MBEDTLS_ERR_RSA_INVALID_PADDING );
valeyev 0:e056ac8fecf8 2051 }
valeyev 0:e056ac8fecf8 2052 }
valeyev 0:e056ac8fecf8 2053
valeyev 0:e056ac8fecf8 2054 /*
valeyev 0:e056ac8fecf8 2055 * Copy the components of an RSA key
valeyev 0:e056ac8fecf8 2056 */
valeyev 0:e056ac8fecf8 2057 int mbedtls_rsa_copy( mbedtls_rsa_context *dst, const mbedtls_rsa_context *src )
valeyev 0:e056ac8fecf8 2058 {
valeyev 0:e056ac8fecf8 2059 int ret;
valeyev 0:e056ac8fecf8 2060
valeyev 0:e056ac8fecf8 2061 dst->ver = src->ver;
valeyev 0:e056ac8fecf8 2062 dst->len = src->len;
valeyev 0:e056ac8fecf8 2063
valeyev 0:e056ac8fecf8 2064 MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->N, &src->N ) );
valeyev 0:e056ac8fecf8 2065 MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->E, &src->E ) );
valeyev 0:e056ac8fecf8 2066
valeyev 0:e056ac8fecf8 2067 MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->D, &src->D ) );
valeyev 0:e056ac8fecf8 2068 MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->P, &src->P ) );
valeyev 0:e056ac8fecf8 2069 MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->Q, &src->Q ) );
valeyev 0:e056ac8fecf8 2070
valeyev 0:e056ac8fecf8 2071 #if !defined(MBEDTLS_RSA_NO_CRT)
valeyev 0:e056ac8fecf8 2072 MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->DP, &src->DP ) );
valeyev 0:e056ac8fecf8 2073 MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->DQ, &src->DQ ) );
valeyev 0:e056ac8fecf8 2074 MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->QP, &src->QP ) );
valeyev 0:e056ac8fecf8 2075 MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->RP, &src->RP ) );
valeyev 0:e056ac8fecf8 2076 MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->RQ, &src->RQ ) );
valeyev 0:e056ac8fecf8 2077 #endif
valeyev 0:e056ac8fecf8 2078
valeyev 0:e056ac8fecf8 2079 MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->RN, &src->RN ) );
valeyev 0:e056ac8fecf8 2080
valeyev 0:e056ac8fecf8 2081 MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->Vi, &src->Vi ) );
valeyev 0:e056ac8fecf8 2082 MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &dst->Vf, &src->Vf ) );
valeyev 0:e056ac8fecf8 2083
valeyev 0:e056ac8fecf8 2084 dst->padding = src->padding;
valeyev 0:e056ac8fecf8 2085 dst->hash_id = src->hash_id;
valeyev 0:e056ac8fecf8 2086
valeyev 0:e056ac8fecf8 2087 cleanup:
valeyev 0:e056ac8fecf8 2088 if( ret != 0 )
valeyev 0:e056ac8fecf8 2089 mbedtls_rsa_free( dst );
valeyev 0:e056ac8fecf8 2090
valeyev 0:e056ac8fecf8 2091 return( ret );
valeyev 0:e056ac8fecf8 2092 }
valeyev 0:e056ac8fecf8 2093
valeyev 0:e056ac8fecf8 2094 /*
valeyev 0:e056ac8fecf8 2095 * Free the components of an RSA key
valeyev 0:e056ac8fecf8 2096 */
valeyev 0:e056ac8fecf8 2097 void mbedtls_rsa_free( mbedtls_rsa_context *ctx )
valeyev 0:e056ac8fecf8 2098 {
valeyev 0:e056ac8fecf8 2099 mbedtls_mpi_free( &ctx->Vi ); mbedtls_mpi_free( &ctx->Vf );
valeyev 0:e056ac8fecf8 2100 mbedtls_mpi_free( &ctx->RN ); mbedtls_mpi_free( &ctx->D );
valeyev 0:e056ac8fecf8 2101 mbedtls_mpi_free( &ctx->Q ); mbedtls_mpi_free( &ctx->P );
valeyev 0:e056ac8fecf8 2102 mbedtls_mpi_free( &ctx->E ); mbedtls_mpi_free( &ctx->N );
valeyev 0:e056ac8fecf8 2103
valeyev 0:e056ac8fecf8 2104 #if !defined(MBEDTLS_RSA_NO_CRT)
valeyev 0:e056ac8fecf8 2105 mbedtls_mpi_free( &ctx->RQ ); mbedtls_mpi_free( &ctx->RP );
valeyev 0:e056ac8fecf8 2106 mbedtls_mpi_free( &ctx->QP ); mbedtls_mpi_free( &ctx->DQ );
valeyev 0:e056ac8fecf8 2107 mbedtls_mpi_free( &ctx->DP );
valeyev 0:e056ac8fecf8 2108 #endif /* MBEDTLS_RSA_NO_CRT */
valeyev 0:e056ac8fecf8 2109
valeyev 0:e056ac8fecf8 2110 #if defined(MBEDTLS_THREADING_C)
valeyev 0:e056ac8fecf8 2111 mbedtls_mutex_free( &ctx->mutex );
valeyev 0:e056ac8fecf8 2112 #endif
valeyev 0:e056ac8fecf8 2113 }
valeyev 0:e056ac8fecf8 2114
valeyev 0:e056ac8fecf8 2115 #endif /* !MBEDTLS_RSA_ALT */
valeyev 0:e056ac8fecf8 2116
valeyev 0:e056ac8fecf8 2117 #if defined(MBEDTLS_SELF_TEST)
valeyev 0:e056ac8fecf8 2118
valeyev 0:e056ac8fecf8 2119 #include "mbedtls/sha1.h"
valeyev 0:e056ac8fecf8 2120
valeyev 0:e056ac8fecf8 2121 /*
valeyev 0:e056ac8fecf8 2122 * Example RSA-1024 keypair, for test purposes
valeyev 0:e056ac8fecf8 2123 */
valeyev 0:e056ac8fecf8 2124 #define KEY_LEN 128
valeyev 0:e056ac8fecf8 2125
valeyev 0:e056ac8fecf8 2126 #define RSA_N "9292758453063D803DD603D5E777D788" \
valeyev 0:e056ac8fecf8 2127 "8ED1D5BF35786190FA2F23EBC0848AEA" \
valeyev 0:e056ac8fecf8 2128 "DDA92CA6C3D80B32C4D109BE0F36D6AE" \
valeyev 0:e056ac8fecf8 2129 "7130B9CED7ACDF54CFC7555AC14EEBAB" \
valeyev 0:e056ac8fecf8 2130 "93A89813FBF3C4F8066D2D800F7C38A8" \
valeyev 0:e056ac8fecf8 2131 "1AE31942917403FF4946B0A83D3D3E05" \
valeyev 0:e056ac8fecf8 2132 "EE57C6F5F5606FB5D4BC6CD34EE0801A" \
valeyev 0:e056ac8fecf8 2133 "5E94BB77B07507233A0BC7BAC8F90F79"
valeyev 0:e056ac8fecf8 2134
valeyev 0:e056ac8fecf8 2135 #define RSA_E "10001"
valeyev 0:e056ac8fecf8 2136
valeyev 0:e056ac8fecf8 2137 #define RSA_D "24BF6185468786FDD303083D25E64EFC" \
valeyev 0:e056ac8fecf8 2138 "66CA472BC44D253102F8B4A9D3BFA750" \
valeyev 0:e056ac8fecf8 2139 "91386C0077937FE33FA3252D28855837" \
valeyev 0:e056ac8fecf8 2140 "AE1B484A8A9A45F7EE8C0C634F99E8CD" \
valeyev 0:e056ac8fecf8 2141 "DF79C5CE07EE72C7F123142198164234" \
valeyev 0:e056ac8fecf8 2142 "CABB724CF78B8173B9F880FC86322407" \
valeyev 0:e056ac8fecf8 2143 "AF1FEDFDDE2BEB674CA15F3E81A1521E" \
valeyev 0:e056ac8fecf8 2144 "071513A1E85B5DFA031F21ECAE91A34D"
valeyev 0:e056ac8fecf8 2145
valeyev 0:e056ac8fecf8 2146 #define RSA_P "C36D0EB7FCD285223CFB5AABA5BDA3D8" \
valeyev 0:e056ac8fecf8 2147 "2C01CAD19EA484A87EA4377637E75500" \
valeyev 0:e056ac8fecf8 2148 "FCB2005C5C7DD6EC4AC023CDA285D796" \
valeyev 0:e056ac8fecf8 2149 "C3D9E75E1EFC42488BB4F1D13AC30A57"
valeyev 0:e056ac8fecf8 2150
valeyev 0:e056ac8fecf8 2151 #define RSA_Q "C000DF51A7C77AE8D7C7370C1FF55B69" \
valeyev 0:e056ac8fecf8 2152 "E211C2B9E5DB1ED0BF61D0D9899620F4" \
valeyev 0:e056ac8fecf8 2153 "910E4168387E3C30AA1E00C339A79508" \
valeyev 0:e056ac8fecf8 2154 "8452DD96A9A5EA5D9DCA68DA636032AF"
valeyev 0:e056ac8fecf8 2155
valeyev 0:e056ac8fecf8 2156 #define PT_LEN 24
valeyev 0:e056ac8fecf8 2157 #define RSA_PT "\xAA\xBB\xCC\x03\x02\x01\x00\xFF\xFF\xFF\xFF\xFF" \
valeyev 0:e056ac8fecf8 2158 "\x11\x22\x33\x0A\x0B\x0C\xCC\xDD\xDD\xDD\xDD\xDD"
valeyev 0:e056ac8fecf8 2159
valeyev 0:e056ac8fecf8 2160 #if defined(MBEDTLS_PKCS1_V15)
valeyev 0:e056ac8fecf8 2161 static int myrand( void *rng_state, unsigned char *output, size_t len )
valeyev 0:e056ac8fecf8 2162 {
valeyev 0:e056ac8fecf8 2163 #if !defined(__OpenBSD__)
valeyev 0:e056ac8fecf8 2164 size_t i;
valeyev 0:e056ac8fecf8 2165
valeyev 0:e056ac8fecf8 2166 if( rng_state != NULL )
valeyev 0:e056ac8fecf8 2167 rng_state = NULL;
valeyev 0:e056ac8fecf8 2168
valeyev 0:e056ac8fecf8 2169 for( i = 0; i < len; ++i )
valeyev 0:e056ac8fecf8 2170 output[i] = rand();
valeyev 0:e056ac8fecf8 2171 #else
valeyev 0:e056ac8fecf8 2172 if( rng_state != NULL )
valeyev 0:e056ac8fecf8 2173 rng_state = NULL;
valeyev 0:e056ac8fecf8 2174
valeyev 0:e056ac8fecf8 2175 arc4random_buf( output, len );
valeyev 0:e056ac8fecf8 2176 #endif /* !OpenBSD */
valeyev 0:e056ac8fecf8 2177
valeyev 0:e056ac8fecf8 2178 return( 0 );
valeyev 0:e056ac8fecf8 2179 }
valeyev 0:e056ac8fecf8 2180 #endif /* MBEDTLS_PKCS1_V15 */
valeyev 0:e056ac8fecf8 2181
valeyev 0:e056ac8fecf8 2182 /*
valeyev 0:e056ac8fecf8 2183 * Checkup routine
valeyev 0:e056ac8fecf8 2184 */
valeyev 0:e056ac8fecf8 2185 int mbedtls_rsa_self_test( int verbose )
valeyev 0:e056ac8fecf8 2186 {
valeyev 0:e056ac8fecf8 2187 int ret = 0;
valeyev 0:e056ac8fecf8 2188 #if defined(MBEDTLS_PKCS1_V15)
valeyev 0:e056ac8fecf8 2189 size_t len;
valeyev 0:e056ac8fecf8 2190 mbedtls_rsa_context rsa;
valeyev 0:e056ac8fecf8 2191 unsigned char rsa_plaintext[PT_LEN];
valeyev 0:e056ac8fecf8 2192 unsigned char rsa_decrypted[PT_LEN];
valeyev 0:e056ac8fecf8 2193 unsigned char rsa_ciphertext[KEY_LEN];
valeyev 0:e056ac8fecf8 2194 #if defined(MBEDTLS_SHA1_C)
valeyev 0:e056ac8fecf8 2195 unsigned char sha1sum[20];
valeyev 0:e056ac8fecf8 2196 #endif
valeyev 0:e056ac8fecf8 2197
valeyev 0:e056ac8fecf8 2198 mbedtls_mpi K;
valeyev 0:e056ac8fecf8 2199
valeyev 0:e056ac8fecf8 2200 mbedtls_mpi_init( &K );
valeyev 0:e056ac8fecf8 2201 mbedtls_rsa_init( &rsa, MBEDTLS_RSA_PKCS_V15, 0 );
valeyev 0:e056ac8fecf8 2202
valeyev 0:e056ac8fecf8 2203 MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &K, 16, RSA_N ) );
valeyev 0:e056ac8fecf8 2204 MBEDTLS_MPI_CHK( mbedtls_rsa_import( &rsa, &K, NULL, NULL, NULL, NULL ) );
valeyev 0:e056ac8fecf8 2205 MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &K, 16, RSA_P ) );
valeyev 0:e056ac8fecf8 2206 MBEDTLS_MPI_CHK( mbedtls_rsa_import( &rsa, NULL, &K, NULL, NULL, NULL ) );
valeyev 0:e056ac8fecf8 2207 MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &K, 16, RSA_Q ) );
valeyev 0:e056ac8fecf8 2208 MBEDTLS_MPI_CHK( mbedtls_rsa_import( &rsa, NULL, NULL, &K, NULL, NULL ) );
valeyev 0:e056ac8fecf8 2209 MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &K, 16, RSA_D ) );
valeyev 0:e056ac8fecf8 2210 MBEDTLS_MPI_CHK( mbedtls_rsa_import( &rsa, NULL, NULL, NULL, &K, NULL ) );
valeyev 0:e056ac8fecf8 2211 MBEDTLS_MPI_CHK( mbedtls_mpi_read_string( &K, 16, RSA_E ) );
valeyev 0:e056ac8fecf8 2212 MBEDTLS_MPI_CHK( mbedtls_rsa_import( &rsa, NULL, NULL, NULL, NULL, &K ) );
valeyev 0:e056ac8fecf8 2213
valeyev 0:e056ac8fecf8 2214 MBEDTLS_MPI_CHK( mbedtls_rsa_complete( &rsa ) );
valeyev 0:e056ac8fecf8 2215
valeyev 0:e056ac8fecf8 2216 if( verbose != 0 )
valeyev 0:e056ac8fecf8 2217 mbedtls_printf( " RSA key validation: " );
valeyev 0:e056ac8fecf8 2218
valeyev 0:e056ac8fecf8 2219 if( mbedtls_rsa_check_pubkey( &rsa ) != 0 ||
valeyev 0:e056ac8fecf8 2220 mbedtls_rsa_check_privkey( &rsa ) != 0 )
valeyev 0:e056ac8fecf8 2221 {
valeyev 0:e056ac8fecf8 2222 if( verbose != 0 )
valeyev 0:e056ac8fecf8 2223 mbedtls_printf( "failed\n" );
valeyev 0:e056ac8fecf8 2224
valeyev 0:e056ac8fecf8 2225 return( 1 );
valeyev 0:e056ac8fecf8 2226 }
valeyev 0:e056ac8fecf8 2227
valeyev 0:e056ac8fecf8 2228 if( verbose != 0 )
valeyev 0:e056ac8fecf8 2229 mbedtls_printf( "passed\n PKCS#1 encryption : " );
valeyev 0:e056ac8fecf8 2230
valeyev 0:e056ac8fecf8 2231 memcpy( rsa_plaintext, RSA_PT, PT_LEN );
valeyev 0:e056ac8fecf8 2232
valeyev 0:e056ac8fecf8 2233 if( mbedtls_rsa_pkcs1_encrypt( &rsa, myrand, NULL, MBEDTLS_RSA_PUBLIC,
valeyev 0:e056ac8fecf8 2234 PT_LEN, rsa_plaintext,
valeyev 0:e056ac8fecf8 2235 rsa_ciphertext ) != 0 )
valeyev 0:e056ac8fecf8 2236 {
valeyev 0:e056ac8fecf8 2237 if( verbose != 0 )
valeyev 0:e056ac8fecf8 2238 mbedtls_printf( "failed\n" );
valeyev 0:e056ac8fecf8 2239
valeyev 0:e056ac8fecf8 2240 return( 1 );
valeyev 0:e056ac8fecf8 2241 }
valeyev 0:e056ac8fecf8 2242
valeyev 0:e056ac8fecf8 2243 if( verbose != 0 )
valeyev 0:e056ac8fecf8 2244 mbedtls_printf( "passed\n PKCS#1 decryption : " );
valeyev 0:e056ac8fecf8 2245
valeyev 0:e056ac8fecf8 2246 if( mbedtls_rsa_pkcs1_decrypt( &rsa, myrand, NULL, MBEDTLS_RSA_PRIVATE,
valeyev 0:e056ac8fecf8 2247 &len, rsa_ciphertext, rsa_decrypted,
valeyev 0:e056ac8fecf8 2248 sizeof(rsa_decrypted) ) != 0 )
valeyev 0:e056ac8fecf8 2249 {
valeyev 0:e056ac8fecf8 2250 if( verbose != 0 )
valeyev 0:e056ac8fecf8 2251 mbedtls_printf( "failed\n" );
valeyev 0:e056ac8fecf8 2252
valeyev 0:e056ac8fecf8 2253 return( 1 );
valeyev 0:e056ac8fecf8 2254 }
valeyev 0:e056ac8fecf8 2255
valeyev 0:e056ac8fecf8 2256 if( memcmp( rsa_decrypted, rsa_plaintext, len ) != 0 )
valeyev 0:e056ac8fecf8 2257 {
valeyev 0:e056ac8fecf8 2258 if( verbose != 0 )
valeyev 0:e056ac8fecf8 2259 mbedtls_printf( "failed\n" );
valeyev 0:e056ac8fecf8 2260
valeyev 0:e056ac8fecf8 2261 return( 1 );
valeyev 0:e056ac8fecf8 2262 }
valeyev 0:e056ac8fecf8 2263
valeyev 0:e056ac8fecf8 2264 if( verbose != 0 )
valeyev 0:e056ac8fecf8 2265 mbedtls_printf( "passed\n" );
valeyev 0:e056ac8fecf8 2266
valeyev 0:e056ac8fecf8 2267 #if defined(MBEDTLS_SHA1_C)
valeyev 0:e056ac8fecf8 2268 if( verbose != 0 )
valeyev 0:e056ac8fecf8 2269 mbedtls_printf( " PKCS#1 data sign : " );
valeyev 0:e056ac8fecf8 2270
valeyev 0:e056ac8fecf8 2271 if( mbedtls_sha1_ret( rsa_plaintext, PT_LEN, sha1sum ) != 0 )
valeyev 0:e056ac8fecf8 2272 {
valeyev 0:e056ac8fecf8 2273 if( verbose != 0 )
valeyev 0:e056ac8fecf8 2274 mbedtls_printf( "failed\n" );
valeyev 0:e056ac8fecf8 2275
valeyev 0:e056ac8fecf8 2276 return( 1 );
valeyev 0:e056ac8fecf8 2277 }
valeyev 0:e056ac8fecf8 2278
valeyev 0:e056ac8fecf8 2279 if( mbedtls_rsa_pkcs1_sign( &rsa, myrand, NULL,
valeyev 0:e056ac8fecf8 2280 MBEDTLS_RSA_PRIVATE, MBEDTLS_MD_SHA1, 0,
valeyev 0:e056ac8fecf8 2281 sha1sum, rsa_ciphertext ) != 0 )
valeyev 0:e056ac8fecf8 2282 {
valeyev 0:e056ac8fecf8 2283 if( verbose != 0 )
valeyev 0:e056ac8fecf8 2284 mbedtls_printf( "failed\n" );
valeyev 0:e056ac8fecf8 2285
valeyev 0:e056ac8fecf8 2286 return( 1 );
valeyev 0:e056ac8fecf8 2287 }
valeyev 0:e056ac8fecf8 2288
valeyev 0:e056ac8fecf8 2289 if( verbose != 0 )
valeyev 0:e056ac8fecf8 2290 mbedtls_printf( "passed\n PKCS#1 sig. verify: " );
valeyev 0:e056ac8fecf8 2291
valeyev 0:e056ac8fecf8 2292 if( mbedtls_rsa_pkcs1_verify( &rsa, NULL, NULL,
valeyev 0:e056ac8fecf8 2293 MBEDTLS_RSA_PUBLIC, MBEDTLS_MD_SHA1, 0,
valeyev 0:e056ac8fecf8 2294 sha1sum, rsa_ciphertext ) != 0 )
valeyev 0:e056ac8fecf8 2295 {
valeyev 0:e056ac8fecf8 2296 if( verbose != 0 )
valeyev 0:e056ac8fecf8 2297 mbedtls_printf( "failed\n" );
valeyev 0:e056ac8fecf8 2298
valeyev 0:e056ac8fecf8 2299 return( 1 );
valeyev 0:e056ac8fecf8 2300 }
valeyev 0:e056ac8fecf8 2301
valeyev 0:e056ac8fecf8 2302 if( verbose != 0 )
valeyev 0:e056ac8fecf8 2303 mbedtls_printf( "passed\n" );
valeyev 0:e056ac8fecf8 2304 #endif /* MBEDTLS_SHA1_C */
valeyev 0:e056ac8fecf8 2305
valeyev 0:e056ac8fecf8 2306 if( verbose != 0 )
valeyev 0:e056ac8fecf8 2307 mbedtls_printf( "\n" );
valeyev 0:e056ac8fecf8 2308
valeyev 0:e056ac8fecf8 2309 cleanup:
valeyev 0:e056ac8fecf8 2310 mbedtls_mpi_free( &K );
valeyev 0:e056ac8fecf8 2311 mbedtls_rsa_free( &rsa );
valeyev 0:e056ac8fecf8 2312 #else /* MBEDTLS_PKCS1_V15 */
valeyev 0:e056ac8fecf8 2313 ((void) verbose);
valeyev 0:e056ac8fecf8 2314 #endif /* MBEDTLS_PKCS1_V15 */
valeyev 0:e056ac8fecf8 2315 return( ret );
valeyev 0:e056ac8fecf8 2316 }
valeyev 0:e056ac8fecf8 2317
valeyev 0:e056ac8fecf8 2318 #endif /* MBEDTLS_SELF_TEST */
valeyev 0:e056ac8fecf8 2319
valeyev 0:e056ac8fecf8 2320 #endif /* MBEDTLS_RSA_C */