Marco Zecchini / Mbed OS Example_RTOS

Rtos API example

mbed-os/features/mbedtls/src/ccm.c@0:9fca2b23d0ba, 2019-02-23 (annotated)

Committer:
marcozecchini
Date:
Sat Feb 23 12:13:36 2019 +0000
Revision:
0:9fca2b23d0ba
final commit

Who changed what in which revision?

UserRevisionLine numberNew contents of line
marcozecchini 0:9fca2b23d0ba 1 /*
marcozecchini 0:9fca2b23d0ba 2 * NIST SP800-38C compliant CCM implementation
marcozecchini 0:9fca2b23d0ba 3 *
marcozecchini 0:9fca2b23d0ba 4 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
marcozecchini 0:9fca2b23d0ba 5 * SPDX-License-Identifier: Apache-2.0
marcozecchini 0:9fca2b23d0ba 6 *
marcozecchini 0:9fca2b23d0ba 7 * Licensed under the Apache License, Version 2.0 (the "License"); you may
marcozecchini 0:9fca2b23d0ba 8 * not use this file except in compliance with the License.
marcozecchini 0:9fca2b23d0ba 9 * You may obtain a copy of the License at
marcozecchini 0:9fca2b23d0ba 10 *
marcozecchini 0:9fca2b23d0ba 11 * http://www.apache.org/licenses/LICENSE-2.0
marcozecchini 0:9fca2b23d0ba 12 *
marcozecchini 0:9fca2b23d0ba 13 * Unless required by applicable law or agreed to in writing, software
marcozecchini 0:9fca2b23d0ba 14 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
marcozecchini 0:9fca2b23d0ba 15 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
marcozecchini 0:9fca2b23d0ba 16 * See the License for the specific language governing permissions and
marcozecchini 0:9fca2b23d0ba 17 * limitations under the License.
marcozecchini 0:9fca2b23d0ba 18 *
marcozecchini 0:9fca2b23d0ba 19 * This file is part of mbed TLS (https://tls.mbed.org)
marcozecchini 0:9fca2b23d0ba 20 */
marcozecchini 0:9fca2b23d0ba 21
marcozecchini 0:9fca2b23d0ba 22 /*
marcozecchini 0:9fca2b23d0ba 23 * Definition of CCM:
marcozecchini 0:9fca2b23d0ba 24 * http://csrc.nist.gov/publications/nistpubs/800-38C/SP800-38C_updated-July20_2007.pdf
marcozecchini 0:9fca2b23d0ba 25 * RFC 3610 "Counter with CBC-MAC (CCM)"
marcozecchini 0:9fca2b23d0ba 26 *
marcozecchini 0:9fca2b23d0ba 27 * Related:
marcozecchini 0:9fca2b23d0ba 28 * RFC 5116 "An Interface and Algorithms for Authenticated Encryption"
marcozecchini 0:9fca2b23d0ba 29 */
marcozecchini 0:9fca2b23d0ba 30
marcozecchini 0:9fca2b23d0ba 31 #if !defined(MBEDTLS_CONFIG_FILE)
marcozecchini 0:9fca2b23d0ba 32 #include "mbedtls/config.h"
marcozecchini 0:9fca2b23d0ba 33 #else
marcozecchini 0:9fca2b23d0ba 34 #include MBEDTLS_CONFIG_FILE
marcozecchini 0:9fca2b23d0ba 35 #endif
marcozecchini 0:9fca2b23d0ba 36
marcozecchini 0:9fca2b23d0ba 37 #if defined(MBEDTLS_CCM_C)
marcozecchini 0:9fca2b23d0ba 38
marcozecchini 0:9fca2b23d0ba 39 #include "mbedtls/ccm.h"
marcozecchini 0:9fca2b23d0ba 40
marcozecchini 0:9fca2b23d0ba 41 #include <string.h>
marcozecchini 0:9fca2b23d0ba 42
marcozecchini 0:9fca2b23d0ba 43 #if defined(MBEDTLS_SELF_TEST) && defined(MBEDTLS_AES_C)
marcozecchini 0:9fca2b23d0ba 44 #if defined(MBEDTLS_PLATFORM_C)
marcozecchini 0:9fca2b23d0ba 45 #include "mbedtls/platform.h"
marcozecchini 0:9fca2b23d0ba 46 #else
marcozecchini 0:9fca2b23d0ba 47 #include <stdio.h>
marcozecchini 0:9fca2b23d0ba 48 #define mbedtls_printf printf
marcozecchini 0:9fca2b23d0ba 49 #endif /* MBEDTLS_PLATFORM_C */
marcozecchini 0:9fca2b23d0ba 50 #endif /* MBEDTLS_SELF_TEST && MBEDTLS_AES_C */
marcozecchini 0:9fca2b23d0ba 51
marcozecchini 0:9fca2b23d0ba 52 /* Implementation that should never be optimized out by the compiler */
marcozecchini 0:9fca2b23d0ba 53 static void mbedtls_zeroize( void *v, size_t n ) {
marcozecchini 0:9fca2b23d0ba 54 volatile unsigned char *p = (unsigned char*)v; while( n-- ) *p++ = 0;
marcozecchini 0:9fca2b23d0ba 55 }
marcozecchini 0:9fca2b23d0ba 56
marcozecchini 0:9fca2b23d0ba 57 #define CCM_ENCRYPT 0
marcozecchini 0:9fca2b23d0ba 58 #define CCM_DECRYPT 1
marcozecchini 0:9fca2b23d0ba 59
marcozecchini 0:9fca2b23d0ba 60 /*
marcozecchini 0:9fca2b23d0ba 61 * Initialize context
marcozecchini 0:9fca2b23d0ba 62 */
marcozecchini 0:9fca2b23d0ba 63 void mbedtls_ccm_init( mbedtls_ccm_context *ctx )
marcozecchini 0:9fca2b23d0ba 64 {
marcozecchini 0:9fca2b23d0ba 65 memset( ctx, 0, sizeof( mbedtls_ccm_context ) );
marcozecchini 0:9fca2b23d0ba 66 }
marcozecchini 0:9fca2b23d0ba 67
marcozecchini 0:9fca2b23d0ba 68 int mbedtls_ccm_setkey( mbedtls_ccm_context *ctx,
marcozecchini 0:9fca2b23d0ba 69 mbedtls_cipher_id_t cipher,
marcozecchini 0:9fca2b23d0ba 70 const unsigned char *key,
marcozecchini 0:9fca2b23d0ba 71 unsigned int keybits )
marcozecchini 0:9fca2b23d0ba 72 {
marcozecchini 0:9fca2b23d0ba 73 int ret;
marcozecchini 0:9fca2b23d0ba 74 const mbedtls_cipher_info_t *cipher_info;
marcozecchini 0:9fca2b23d0ba 75
marcozecchini 0:9fca2b23d0ba 76 cipher_info = mbedtls_cipher_info_from_values( cipher, keybits, MBEDTLS_MODE_ECB );
marcozecchini 0:9fca2b23d0ba 77 if( cipher_info == NULL )
marcozecchini 0:9fca2b23d0ba 78 return( MBEDTLS_ERR_CCM_BAD_INPUT );
marcozecchini 0:9fca2b23d0ba 79
marcozecchini 0:9fca2b23d0ba 80 if( cipher_info->block_size != 16 )
marcozecchini 0:9fca2b23d0ba 81 return( MBEDTLS_ERR_CCM_BAD_INPUT );
marcozecchini 0:9fca2b23d0ba 82
marcozecchini 0:9fca2b23d0ba 83 mbedtls_cipher_free( &ctx->cipher_ctx );
marcozecchini 0:9fca2b23d0ba 84
marcozecchini 0:9fca2b23d0ba 85 if( ( ret = mbedtls_cipher_setup( &ctx->cipher_ctx, cipher_info ) ) != 0 )
marcozecchini 0:9fca2b23d0ba 86 return( ret );
marcozecchini 0:9fca2b23d0ba 87
marcozecchini 0:9fca2b23d0ba 88 if( ( ret = mbedtls_cipher_setkey( &ctx->cipher_ctx, key, keybits,
marcozecchini 0:9fca2b23d0ba 89 MBEDTLS_ENCRYPT ) ) != 0 )
marcozecchini 0:9fca2b23d0ba 90 {
marcozecchini 0:9fca2b23d0ba 91 return( ret );
marcozecchini 0:9fca2b23d0ba 92 }
marcozecchini 0:9fca2b23d0ba 93
marcozecchini 0:9fca2b23d0ba 94 return( 0 );
marcozecchini 0:9fca2b23d0ba 95 }
marcozecchini 0:9fca2b23d0ba 96
marcozecchini 0:9fca2b23d0ba 97 /*
marcozecchini 0:9fca2b23d0ba 98 * Free context
marcozecchini 0:9fca2b23d0ba 99 */
marcozecchini 0:9fca2b23d0ba 100 void mbedtls_ccm_free( mbedtls_ccm_context *ctx )
marcozecchini 0:9fca2b23d0ba 101 {
marcozecchini 0:9fca2b23d0ba 102 mbedtls_cipher_free( &ctx->cipher_ctx );
marcozecchini 0:9fca2b23d0ba 103 mbedtls_zeroize( ctx, sizeof( mbedtls_ccm_context ) );
marcozecchini 0:9fca2b23d0ba 104 }
marcozecchini 0:9fca2b23d0ba 105
marcozecchini 0:9fca2b23d0ba 106 /*
marcozecchini 0:9fca2b23d0ba 107 * Macros for common operations.
marcozecchini 0:9fca2b23d0ba 108 * Results in smaller compiled code than static inline functions.
marcozecchini 0:9fca2b23d0ba 109 */
marcozecchini 0:9fca2b23d0ba 110
marcozecchini 0:9fca2b23d0ba 111 /*
marcozecchini 0:9fca2b23d0ba 112 * Update the CBC-MAC state in y using a block in b
marcozecchini 0:9fca2b23d0ba 113 * (Always using b as the source helps the compiler optimise a bit better.)
marcozecchini 0:9fca2b23d0ba 114 */
marcozecchini 0:9fca2b23d0ba 115 #define UPDATE_CBC_MAC \
marcozecchini 0:9fca2b23d0ba 116 for( i = 0; i < 16; i++ ) \
marcozecchini 0:9fca2b23d0ba 117 y[i] ^= b[i]; \
marcozecchini 0:9fca2b23d0ba 118 \
marcozecchini 0:9fca2b23d0ba 119 if( ( ret = mbedtls_cipher_update( &ctx->cipher_ctx, y, 16, y, &olen ) ) != 0 ) \
marcozecchini 0:9fca2b23d0ba 120 return( ret );
marcozecchini 0:9fca2b23d0ba 121
marcozecchini 0:9fca2b23d0ba 122 /*
marcozecchini 0:9fca2b23d0ba 123 * Encrypt or decrypt a partial block with CTR
marcozecchini 0:9fca2b23d0ba 124 * Warning: using b for temporary storage! src and dst must not be b!
marcozecchini 0:9fca2b23d0ba 125 * This avoids allocating one more 16 bytes buffer while allowing src == dst.
marcozecchini 0:9fca2b23d0ba 126 */
marcozecchini 0:9fca2b23d0ba 127 #define CTR_CRYPT( dst, src, len ) \
marcozecchini 0:9fca2b23d0ba 128 if( ( ret = mbedtls_cipher_update( &ctx->cipher_ctx, ctr, 16, b, &olen ) ) != 0 ) \
marcozecchini 0:9fca2b23d0ba 129 return( ret ); \
marcozecchini 0:9fca2b23d0ba 130 \
marcozecchini 0:9fca2b23d0ba 131 for( i = 0; i < len; i++ ) \
marcozecchini 0:9fca2b23d0ba 132 dst[i] = src[i] ^ b[i];
marcozecchini 0:9fca2b23d0ba 133
marcozecchini 0:9fca2b23d0ba 134 /*
marcozecchini 0:9fca2b23d0ba 135 * Authenticated encryption or decryption
marcozecchini 0:9fca2b23d0ba 136 */
marcozecchini 0:9fca2b23d0ba 137 static int ccm_auth_crypt( mbedtls_ccm_context *ctx, int mode, size_t length,
marcozecchini 0:9fca2b23d0ba 138 const unsigned char *iv, size_t iv_len,
marcozecchini 0:9fca2b23d0ba 139 const unsigned char *add, size_t add_len,
marcozecchini 0:9fca2b23d0ba 140 const unsigned char *input, unsigned char *output,
marcozecchini 0:9fca2b23d0ba 141 unsigned char *tag, size_t tag_len )
marcozecchini 0:9fca2b23d0ba 142 {
marcozecchini 0:9fca2b23d0ba 143 int ret;
marcozecchini 0:9fca2b23d0ba 144 unsigned char i;
marcozecchini 0:9fca2b23d0ba 145 unsigned char q;
marcozecchini 0:9fca2b23d0ba 146 size_t len_left, olen;
marcozecchini 0:9fca2b23d0ba 147 unsigned char b[16];
marcozecchini 0:9fca2b23d0ba 148 unsigned char y[16];
marcozecchini 0:9fca2b23d0ba 149 unsigned char ctr[16];
marcozecchini 0:9fca2b23d0ba 150 const unsigned char *src;
marcozecchini 0:9fca2b23d0ba 151 unsigned char *dst;
marcozecchini 0:9fca2b23d0ba 152
marcozecchini 0:9fca2b23d0ba 153 /*
marcozecchini 0:9fca2b23d0ba 154 * Check length requirements: SP800-38C A.1
marcozecchini 0:9fca2b23d0ba 155 * Additional requirement: a < 2^16 - 2^8 to simplify the code.
marcozecchini 0:9fca2b23d0ba 156 * 'length' checked later (when writing it to the first block)
marcozecchini 0:9fca2b23d0ba 157 */
marcozecchini 0:9fca2b23d0ba 158 if( tag_len < 4 || tag_len > 16 || tag_len % 2 != 0 )
marcozecchini 0:9fca2b23d0ba 159 return( MBEDTLS_ERR_CCM_BAD_INPUT );
marcozecchini 0:9fca2b23d0ba 160
marcozecchini 0:9fca2b23d0ba 161 /* Also implies q is within bounds */
marcozecchini 0:9fca2b23d0ba 162 if( iv_len < 7 || iv_len > 13 )
marcozecchini 0:9fca2b23d0ba 163 return( MBEDTLS_ERR_CCM_BAD_INPUT );
marcozecchini 0:9fca2b23d0ba 164
marcozecchini 0:9fca2b23d0ba 165 if( add_len > 0xFF00 )
marcozecchini 0:9fca2b23d0ba 166 return( MBEDTLS_ERR_CCM_BAD_INPUT );
marcozecchini 0:9fca2b23d0ba 167
marcozecchini 0:9fca2b23d0ba 168 q = 16 - 1 - (unsigned char) iv_len;
marcozecchini 0:9fca2b23d0ba 169
marcozecchini 0:9fca2b23d0ba 170 /*
marcozecchini 0:9fca2b23d0ba 171 * First block B_0:
marcozecchini 0:9fca2b23d0ba 172 * 0 .. 0 flags
marcozecchini 0:9fca2b23d0ba 173 * 1 .. iv_len nonce (aka iv)
marcozecchini 0:9fca2b23d0ba 174 * iv_len+1 .. 15 length
marcozecchini 0:9fca2b23d0ba 175 *
marcozecchini 0:9fca2b23d0ba 176 * With flags as (bits):
marcozecchini 0:9fca2b23d0ba 177 * 7 0
marcozecchini 0:9fca2b23d0ba 178 * 6 add present?
marcozecchini 0:9fca2b23d0ba 179 * 5 .. 3 (t - 2) / 2
marcozecchini 0:9fca2b23d0ba 180 * 2 .. 0 q - 1
marcozecchini 0:9fca2b23d0ba 181 */
marcozecchini 0:9fca2b23d0ba 182 b[0] = 0;
marcozecchini 0:9fca2b23d0ba 183 b[0] |= ( add_len > 0 ) << 6;
marcozecchini 0:9fca2b23d0ba 184 b[0] |= ( ( tag_len - 2 ) / 2 ) << 3;
marcozecchini 0:9fca2b23d0ba 185 b[0] |= q - 1;
marcozecchini 0:9fca2b23d0ba 186
marcozecchini 0:9fca2b23d0ba 187 memcpy( b + 1, iv, iv_len );
marcozecchini 0:9fca2b23d0ba 188
marcozecchini 0:9fca2b23d0ba 189 for( i = 0, len_left = length; i < q; i++, len_left >>= 8 )
marcozecchini 0:9fca2b23d0ba 190 b[15-i] = (unsigned char)( len_left & 0xFF );
marcozecchini 0:9fca2b23d0ba 191
marcozecchini 0:9fca2b23d0ba 192 if( len_left > 0 )
marcozecchini 0:9fca2b23d0ba 193 return( MBEDTLS_ERR_CCM_BAD_INPUT );
marcozecchini 0:9fca2b23d0ba 194
marcozecchini 0:9fca2b23d0ba 195
marcozecchini 0:9fca2b23d0ba 196 /* Start CBC-MAC with first block */
marcozecchini 0:9fca2b23d0ba 197 memset( y, 0, 16 );
marcozecchini 0:9fca2b23d0ba 198 UPDATE_CBC_MAC;
marcozecchini 0:9fca2b23d0ba 199
marcozecchini 0:9fca2b23d0ba 200 /*
marcozecchini 0:9fca2b23d0ba 201 * If there is additional data, update CBC-MAC with
marcozecchini 0:9fca2b23d0ba 202 * add_len, add, 0 (padding to a block boundary)
marcozecchini 0:9fca2b23d0ba 203 */
marcozecchini 0:9fca2b23d0ba 204 if( add_len > 0 )
marcozecchini 0:9fca2b23d0ba 205 {
marcozecchini 0:9fca2b23d0ba 206 size_t use_len;
marcozecchini 0:9fca2b23d0ba 207 len_left = add_len;
marcozecchini 0:9fca2b23d0ba 208 src = add;
marcozecchini 0:9fca2b23d0ba 209
marcozecchini 0:9fca2b23d0ba 210 memset( b, 0, 16 );
marcozecchini 0:9fca2b23d0ba 211 b[0] = (unsigned char)( ( add_len >> 8 ) & 0xFF );
marcozecchini 0:9fca2b23d0ba 212 b[1] = (unsigned char)( ( add_len ) & 0xFF );
marcozecchini 0:9fca2b23d0ba 213
marcozecchini 0:9fca2b23d0ba 214 use_len = len_left < 16 - 2 ? len_left : 16 - 2;
marcozecchini 0:9fca2b23d0ba 215 memcpy( b + 2, src, use_len );
marcozecchini 0:9fca2b23d0ba 216 len_left -= use_len;
marcozecchini 0:9fca2b23d0ba 217 src += use_len;
marcozecchini 0:9fca2b23d0ba 218
marcozecchini 0:9fca2b23d0ba 219 UPDATE_CBC_MAC;
marcozecchini 0:9fca2b23d0ba 220
marcozecchini 0:9fca2b23d0ba 221 while( len_left > 0 )
marcozecchini 0:9fca2b23d0ba 222 {
marcozecchini 0:9fca2b23d0ba 223 use_len = len_left > 16 ? 16 : len_left;
marcozecchini 0:9fca2b23d0ba 224
marcozecchini 0:9fca2b23d0ba 225 memset( b, 0, 16 );
marcozecchini 0:9fca2b23d0ba 226 memcpy( b, src, use_len );
marcozecchini 0:9fca2b23d0ba 227 UPDATE_CBC_MAC;
marcozecchini 0:9fca2b23d0ba 228
marcozecchini 0:9fca2b23d0ba 229 len_left -= use_len;
marcozecchini 0:9fca2b23d0ba 230 src += use_len;
marcozecchini 0:9fca2b23d0ba 231 }
marcozecchini 0:9fca2b23d0ba 232 }
marcozecchini 0:9fca2b23d0ba 233
marcozecchini 0:9fca2b23d0ba 234 /*
marcozecchini 0:9fca2b23d0ba 235 * Prepare counter block for encryption:
marcozecchini 0:9fca2b23d0ba 236 * 0 .. 0 flags
marcozecchini 0:9fca2b23d0ba 237 * 1 .. iv_len nonce (aka iv)
marcozecchini 0:9fca2b23d0ba 238 * iv_len+1 .. 15 counter (initially 1)
marcozecchini 0:9fca2b23d0ba 239 *
marcozecchini 0:9fca2b23d0ba 240 * With flags as (bits):
marcozecchini 0:9fca2b23d0ba 241 * 7 .. 3 0
marcozecchini 0:9fca2b23d0ba 242 * 2 .. 0 q - 1
marcozecchini 0:9fca2b23d0ba 243 */
marcozecchini 0:9fca2b23d0ba 244 ctr[0] = q - 1;
marcozecchini 0:9fca2b23d0ba 245 memcpy( ctr + 1, iv, iv_len );
marcozecchini 0:9fca2b23d0ba 246 memset( ctr + 1 + iv_len, 0, q );
marcozecchini 0:9fca2b23d0ba 247 ctr[15] = 1;
marcozecchini 0:9fca2b23d0ba 248
marcozecchini 0:9fca2b23d0ba 249 /*
marcozecchini 0:9fca2b23d0ba 250 * Authenticate and {en,de}crypt the message.
marcozecchini 0:9fca2b23d0ba 251 *
marcozecchini 0:9fca2b23d0ba 252 * The only difference between encryption and decryption is
marcozecchini 0:9fca2b23d0ba 253 * the respective order of authentication and {en,de}cryption.
marcozecchini 0:9fca2b23d0ba 254 */
marcozecchini 0:9fca2b23d0ba 255 len_left = length;
marcozecchini 0:9fca2b23d0ba 256 src = input;
marcozecchini 0:9fca2b23d0ba 257 dst = output;
marcozecchini 0:9fca2b23d0ba 258
marcozecchini 0:9fca2b23d0ba 259 while( len_left > 0 )
marcozecchini 0:9fca2b23d0ba 260 {
marcozecchini 0:9fca2b23d0ba 261 size_t use_len = len_left > 16 ? 16 : len_left;
marcozecchini 0:9fca2b23d0ba 262
marcozecchini 0:9fca2b23d0ba 263 if( mode == CCM_ENCRYPT )
marcozecchini 0:9fca2b23d0ba 264 {
marcozecchini 0:9fca2b23d0ba 265 memset( b, 0, 16 );
marcozecchini 0:9fca2b23d0ba 266 memcpy( b, src, use_len );
marcozecchini 0:9fca2b23d0ba 267 UPDATE_CBC_MAC;
marcozecchini 0:9fca2b23d0ba 268 }
marcozecchini 0:9fca2b23d0ba 269
marcozecchini 0:9fca2b23d0ba 270 CTR_CRYPT( dst, src, use_len );
marcozecchini 0:9fca2b23d0ba 271
marcozecchini 0:9fca2b23d0ba 272 if( mode == CCM_DECRYPT )
marcozecchini 0:9fca2b23d0ba 273 {
marcozecchini 0:9fca2b23d0ba 274 memset( b, 0, 16 );
marcozecchini 0:9fca2b23d0ba 275 memcpy( b, dst, use_len );
marcozecchini 0:9fca2b23d0ba 276 UPDATE_CBC_MAC;
marcozecchini 0:9fca2b23d0ba 277 }
marcozecchini 0:9fca2b23d0ba 278
marcozecchini 0:9fca2b23d0ba 279 dst += use_len;
marcozecchini 0:9fca2b23d0ba 280 src += use_len;
marcozecchini 0:9fca2b23d0ba 281 len_left -= use_len;
marcozecchini 0:9fca2b23d0ba 282
marcozecchini 0:9fca2b23d0ba 283 /*
marcozecchini 0:9fca2b23d0ba 284 * Increment counter.
marcozecchini 0:9fca2b23d0ba 285 * No need to check for overflow thanks to the length check above.
marcozecchini 0:9fca2b23d0ba 286 */
marcozecchini 0:9fca2b23d0ba 287 for( i = 0; i < q; i++ )
marcozecchini 0:9fca2b23d0ba 288 if( ++ctr[15-i] != 0 )
marcozecchini 0:9fca2b23d0ba 289 break;
marcozecchini 0:9fca2b23d0ba 290 }
marcozecchini 0:9fca2b23d0ba 291
marcozecchini 0:9fca2b23d0ba 292 /*
marcozecchini 0:9fca2b23d0ba 293 * Authentication: reset counter and crypt/mask internal tag
marcozecchini 0:9fca2b23d0ba 294 */
marcozecchini 0:9fca2b23d0ba 295 for( i = 0; i < q; i++ )
marcozecchini 0:9fca2b23d0ba 296 ctr[15-i] = 0;
marcozecchini 0:9fca2b23d0ba 297
marcozecchini 0:9fca2b23d0ba 298 CTR_CRYPT( y, y, 16 );
marcozecchini 0:9fca2b23d0ba 299 memcpy( tag, y, tag_len );
marcozecchini 0:9fca2b23d0ba 300
marcozecchini 0:9fca2b23d0ba 301 return( 0 );
marcozecchini 0:9fca2b23d0ba 302 }
marcozecchini 0:9fca2b23d0ba 303
marcozecchini 0:9fca2b23d0ba 304 /*
marcozecchini 0:9fca2b23d0ba 305 * Authenticated encryption
marcozecchini 0:9fca2b23d0ba 306 */
marcozecchini 0:9fca2b23d0ba 307 int mbedtls_ccm_encrypt_and_tag( mbedtls_ccm_context *ctx, size_t length,
marcozecchini 0:9fca2b23d0ba 308 const unsigned char *iv, size_t iv_len,
marcozecchini 0:9fca2b23d0ba 309 const unsigned char *add, size_t add_len,
marcozecchini 0:9fca2b23d0ba 310 const unsigned char *input, unsigned char *output,
marcozecchini 0:9fca2b23d0ba 311 unsigned char *tag, size_t tag_len )
marcozecchini 0:9fca2b23d0ba 312 {
marcozecchini 0:9fca2b23d0ba 313 return( ccm_auth_crypt( ctx, CCM_ENCRYPT, length, iv, iv_len,
marcozecchini 0:9fca2b23d0ba 314 add, add_len, input, output, tag, tag_len ) );
marcozecchini 0:9fca2b23d0ba 315 }
marcozecchini 0:9fca2b23d0ba 316
marcozecchini 0:9fca2b23d0ba 317 /*
marcozecchini 0:9fca2b23d0ba 318 * Authenticated decryption
marcozecchini 0:9fca2b23d0ba 319 */
marcozecchini 0:9fca2b23d0ba 320 int mbedtls_ccm_auth_decrypt( mbedtls_ccm_context *ctx, size_t length,
marcozecchini 0:9fca2b23d0ba 321 const unsigned char *iv, size_t iv_len,
marcozecchini 0:9fca2b23d0ba 322 const unsigned char *add, size_t add_len,
marcozecchini 0:9fca2b23d0ba 323 const unsigned char *input, unsigned char *output,
marcozecchini 0:9fca2b23d0ba 324 const unsigned char *tag, size_t tag_len )
marcozecchini 0:9fca2b23d0ba 325 {
marcozecchini 0:9fca2b23d0ba 326 int ret;
marcozecchini 0:9fca2b23d0ba 327 unsigned char check_tag[16];
marcozecchini 0:9fca2b23d0ba 328 unsigned char i;
marcozecchini 0:9fca2b23d0ba 329 int diff;
marcozecchini 0:9fca2b23d0ba 330
marcozecchini 0:9fca2b23d0ba 331 if( ( ret = ccm_auth_crypt( ctx, CCM_DECRYPT, length,
marcozecchini 0:9fca2b23d0ba 332 iv, iv_len, add, add_len,
marcozecchini 0:9fca2b23d0ba 333 input, output, check_tag, tag_len ) ) != 0 )
marcozecchini 0:9fca2b23d0ba 334 {
marcozecchini 0:9fca2b23d0ba 335 return( ret );
marcozecchini 0:9fca2b23d0ba 336 }
marcozecchini 0:9fca2b23d0ba 337
marcozecchini 0:9fca2b23d0ba 338 /* Check tag in "constant-time" */
marcozecchini 0:9fca2b23d0ba 339 for( diff = 0, i = 0; i < tag_len; i++ )
marcozecchini 0:9fca2b23d0ba 340 diff |= tag[i] ^ check_tag[i];
marcozecchini 0:9fca2b23d0ba 341
marcozecchini 0:9fca2b23d0ba 342 if( diff != 0 )
marcozecchini 0:9fca2b23d0ba 343 {
marcozecchini 0:9fca2b23d0ba 344 mbedtls_zeroize( output, length );
marcozecchini 0:9fca2b23d0ba 345 return( MBEDTLS_ERR_CCM_AUTH_FAILED );
marcozecchini 0:9fca2b23d0ba 346 }
marcozecchini 0:9fca2b23d0ba 347
marcozecchini 0:9fca2b23d0ba 348 return( 0 );
marcozecchini 0:9fca2b23d0ba 349 }
marcozecchini 0:9fca2b23d0ba 350
marcozecchini 0:9fca2b23d0ba 351
marcozecchini 0:9fca2b23d0ba 352 #if defined(MBEDTLS_SELF_TEST) && defined(MBEDTLS_AES_C)
marcozecchini 0:9fca2b23d0ba 353 /*
marcozecchini 0:9fca2b23d0ba 354 * Examples 1 to 3 from SP800-38C Appendix C
marcozecchini 0:9fca2b23d0ba 355 */
marcozecchini 0:9fca2b23d0ba 356
marcozecchini 0:9fca2b23d0ba 357 #define NB_TESTS 3
marcozecchini 0:9fca2b23d0ba 358
marcozecchini 0:9fca2b23d0ba 359 /*
marcozecchini 0:9fca2b23d0ba 360 * The data is the same for all tests, only the used length changes
marcozecchini 0:9fca2b23d0ba 361 */
marcozecchini 0:9fca2b23d0ba 362 static const unsigned char key[] = {
marcozecchini 0:9fca2b23d0ba 363 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
marcozecchini 0:9fca2b23d0ba 364 0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f
marcozecchini 0:9fca2b23d0ba 365 };
marcozecchini 0:9fca2b23d0ba 366
marcozecchini 0:9fca2b23d0ba 367 static const unsigned char iv[] = {
marcozecchini 0:9fca2b23d0ba 368 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
marcozecchini 0:9fca2b23d0ba 369 0x18, 0x19, 0x1a, 0x1b
marcozecchini 0:9fca2b23d0ba 370 };
marcozecchini 0:9fca2b23d0ba 371
marcozecchini 0:9fca2b23d0ba 372 static const unsigned char ad[] = {
marcozecchini 0:9fca2b23d0ba 373 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
marcozecchini 0:9fca2b23d0ba 374 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
marcozecchini 0:9fca2b23d0ba 375 0x10, 0x11, 0x12, 0x13
marcozecchini 0:9fca2b23d0ba 376 };
marcozecchini 0:9fca2b23d0ba 377
marcozecchini 0:9fca2b23d0ba 378 static const unsigned char msg[] = {
marcozecchini 0:9fca2b23d0ba 379 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
marcozecchini 0:9fca2b23d0ba 380 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
marcozecchini 0:9fca2b23d0ba 381 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
marcozecchini 0:9fca2b23d0ba 382 };
marcozecchini 0:9fca2b23d0ba 383
marcozecchini 0:9fca2b23d0ba 384 static const size_t iv_len [NB_TESTS] = { 7, 8, 12 };
marcozecchini 0:9fca2b23d0ba 385 static const size_t add_len[NB_TESTS] = { 8, 16, 20 };
marcozecchini 0:9fca2b23d0ba 386 static const size_t msg_len[NB_TESTS] = { 4, 16, 24 };
marcozecchini 0:9fca2b23d0ba 387 static const size_t tag_len[NB_TESTS] = { 4, 6, 8 };
marcozecchini 0:9fca2b23d0ba 388
marcozecchini 0:9fca2b23d0ba 389 static const unsigned char res[NB_TESTS][32] = {
marcozecchini 0:9fca2b23d0ba 390 { 0x71, 0x62, 0x01, 0x5b, 0x4d, 0xac, 0x25, 0x5d },
marcozecchini 0:9fca2b23d0ba 391 { 0xd2, 0xa1, 0xf0, 0xe0, 0x51, 0xea, 0x5f, 0x62,
marcozecchini 0:9fca2b23d0ba 392 0x08, 0x1a, 0x77, 0x92, 0x07, 0x3d, 0x59, 0x3d,
marcozecchini 0:9fca2b23d0ba 393 0x1f, 0xc6, 0x4f, 0xbf, 0xac, 0xcd },
marcozecchini 0:9fca2b23d0ba 394 { 0xe3, 0xb2, 0x01, 0xa9, 0xf5, 0xb7, 0x1a, 0x7a,
marcozecchini 0:9fca2b23d0ba 395 0x9b, 0x1c, 0xea, 0xec, 0xcd, 0x97, 0xe7, 0x0b,
marcozecchini 0:9fca2b23d0ba 396 0x61, 0x76, 0xaa, 0xd9, 0xa4, 0x42, 0x8a, 0xa5,
marcozecchini 0:9fca2b23d0ba 397 0x48, 0x43, 0x92, 0xfb, 0xc1, 0xb0, 0x99, 0x51 }
marcozecchini 0:9fca2b23d0ba 398 };
marcozecchini 0:9fca2b23d0ba 399
marcozecchini 0:9fca2b23d0ba 400 int mbedtls_ccm_self_test( int verbose )
marcozecchini 0:9fca2b23d0ba 401 {
marcozecchini 0:9fca2b23d0ba 402 mbedtls_ccm_context ctx;
marcozecchini 0:9fca2b23d0ba 403 unsigned char out[32];
marcozecchini 0:9fca2b23d0ba 404 size_t i;
marcozecchini 0:9fca2b23d0ba 405 int ret;
marcozecchini 0:9fca2b23d0ba 406
marcozecchini 0:9fca2b23d0ba 407 mbedtls_ccm_init( &ctx );
marcozecchini 0:9fca2b23d0ba 408
marcozecchini 0:9fca2b23d0ba 409 if( mbedtls_ccm_setkey( &ctx, MBEDTLS_CIPHER_ID_AES, key, 8 * sizeof key ) != 0 )
marcozecchini 0:9fca2b23d0ba 410 {
marcozecchini 0:9fca2b23d0ba 411 if( verbose != 0 )
marcozecchini 0:9fca2b23d0ba 412 mbedtls_printf( " CCM: setup failed" );
marcozecchini 0:9fca2b23d0ba 413
marcozecchini 0:9fca2b23d0ba 414 return( 1 );
marcozecchini 0:9fca2b23d0ba 415 }
marcozecchini 0:9fca2b23d0ba 416
marcozecchini 0:9fca2b23d0ba 417 for( i = 0; i < NB_TESTS; i++ )
marcozecchini 0:9fca2b23d0ba 418 {
marcozecchini 0:9fca2b23d0ba 419 if( verbose != 0 )
marcozecchini 0:9fca2b23d0ba 420 mbedtls_printf( " CCM-AES #%u: ", (unsigned int) i + 1 );
marcozecchini 0:9fca2b23d0ba 421
marcozecchini 0:9fca2b23d0ba 422 ret = mbedtls_ccm_encrypt_and_tag( &ctx, msg_len[i],
marcozecchini 0:9fca2b23d0ba 423 iv, iv_len[i], ad, add_len[i],
marcozecchini 0:9fca2b23d0ba 424 msg, out,
marcozecchini 0:9fca2b23d0ba 425 out + msg_len[i], tag_len[i] );
marcozecchini 0:9fca2b23d0ba 426
marcozecchini 0:9fca2b23d0ba 427 if( ret != 0 ||
marcozecchini 0:9fca2b23d0ba 428 memcmp( out, res[i], msg_len[i] + tag_len[i] ) != 0 )
marcozecchini 0:9fca2b23d0ba 429 {
marcozecchini 0:9fca2b23d0ba 430 if( verbose != 0 )
marcozecchini 0:9fca2b23d0ba 431 mbedtls_printf( "failed\n" );
marcozecchini 0:9fca2b23d0ba 432
marcozecchini 0:9fca2b23d0ba 433 return( 1 );
marcozecchini 0:9fca2b23d0ba 434 }
marcozecchini 0:9fca2b23d0ba 435
marcozecchini 0:9fca2b23d0ba 436 ret = mbedtls_ccm_auth_decrypt( &ctx, msg_len[i],
marcozecchini 0:9fca2b23d0ba 437 iv, iv_len[i], ad, add_len[i],
marcozecchini 0:9fca2b23d0ba 438 res[i], out,
marcozecchini 0:9fca2b23d0ba 439 res[i] + msg_len[i], tag_len[i] );
marcozecchini 0:9fca2b23d0ba 440
marcozecchini 0:9fca2b23d0ba 441 if( ret != 0 ||
marcozecchini 0:9fca2b23d0ba 442 memcmp( out, msg, msg_len[i] ) != 0 )
marcozecchini 0:9fca2b23d0ba 443 {
marcozecchini 0:9fca2b23d0ba 444 if( verbose != 0 )
marcozecchini 0:9fca2b23d0ba 445 mbedtls_printf( "failed\n" );
marcozecchini 0:9fca2b23d0ba 446
marcozecchini 0:9fca2b23d0ba 447 return( 1 );
marcozecchini 0:9fca2b23d0ba 448 }
marcozecchini 0:9fca2b23d0ba 449
marcozecchini 0:9fca2b23d0ba 450 if( verbose != 0 )
marcozecchini 0:9fca2b23d0ba 451 mbedtls_printf( "passed\n" );
marcozecchini 0:9fca2b23d0ba 452 }
marcozecchini 0:9fca2b23d0ba 453
marcozecchini 0:9fca2b23d0ba 454 mbedtls_ccm_free( &ctx );
marcozecchini 0:9fca2b23d0ba 455
marcozecchini 0:9fca2b23d0ba 456 if( verbose != 0 )
marcozecchini 0:9fca2b23d0ba 457 mbedtls_printf( "\n" );
marcozecchini 0:9fca2b23d0ba 458
marcozecchini 0:9fca2b23d0ba 459 return( 0 );
marcozecchini 0:9fca2b23d0ba 460 }
marcozecchini 0:9fca2b23d0ba 461
marcozecchini 0:9fca2b23d0ba 462 #endif /* MBEDTLS_SELF_TEST && MBEDTLS_AES_C */
marcozecchini 0:9fca2b23d0ba 463
marcozecchini 0:9fca2b23d0ba 464 #endif /* MBEDTLS_CCM_C */