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