Nitin Shukla / LED_Demo

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Dependencies:   MAX44000 nexpaq_mdk

Fork of LED_Demo by Maxim nexpaq

mbd_os/features/mbedtls/src/ccm.c@1:55a6170b404f, 2016-09-17 (annotated)

Committer:
nexpaq
Date:
Sat Sep 17 16:32:05 2016 +0000
Revision:
1:55a6170b404f
checking in for sharing

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nexpaq 1:55a6170b404f 1 /*
nexpaq 1:55a6170b404f 2 * NIST SP800-38C compliant CCM implementation
nexpaq 1:55a6170b404f 3 *
nexpaq 1:55a6170b404f 4 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
nexpaq 1:55a6170b404f 5 * SPDX-License-Identifier: Apache-2.0
nexpaq 1:55a6170b404f 6 *
nexpaq 1:55a6170b404f 7 * Licensed under the Apache License, Version 2.0 (the "License"); you may
nexpaq 1:55a6170b404f 8 * not use this file except in compliance with the License.
nexpaq 1:55a6170b404f 9 * You may obtain a copy of the License at
nexpaq 1:55a6170b404f 10 *
nexpaq 1:55a6170b404f 11 * http://www.apache.org/licenses/LICENSE-2.0
nexpaq 1:55a6170b404f 12 *
nexpaq 1:55a6170b404f 13 * Unless required by applicable law or agreed to in writing, software
nexpaq 1:55a6170b404f 14 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
nexpaq 1:55a6170b404f 15 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
nexpaq 1:55a6170b404f 16 * See the License for the specific language governing permissions and
nexpaq 1:55a6170b404f 17 * limitations under the License.
nexpaq 1:55a6170b404f 18 *
nexpaq 1:55a6170b404f 19 * This file is part of mbed TLS (https://tls.mbed.org)
nexpaq 1:55a6170b404f 20 */
nexpaq 1:55a6170b404f 21
nexpaq 1:55a6170b404f 22 /*
nexpaq 1:55a6170b404f 23 * Definition of CCM:
nexpaq 1:55a6170b404f 24 * http://csrc.nist.gov/publications/nistpubs/800-38C/SP800-38C_updated-July20_2007.pdf
nexpaq 1:55a6170b404f 25 * RFC 3610 "Counter with CBC-MAC (CCM)"
nexpaq 1:55a6170b404f 26 *
nexpaq 1:55a6170b404f 27 * Related:
nexpaq 1:55a6170b404f 28 * RFC 5116 "An Interface and Algorithms for Authenticated Encryption"
nexpaq 1:55a6170b404f 29 */
nexpaq 1:55a6170b404f 30
nexpaq 1:55a6170b404f 31 #if !defined(MBEDTLS_CONFIG_FILE)
nexpaq 1:55a6170b404f 32 #include "mbedtls/config.h"
nexpaq 1:55a6170b404f 33 #else
nexpaq 1:55a6170b404f 34 #include MBEDTLS_CONFIG_FILE
nexpaq 1:55a6170b404f 35 #endif
nexpaq 1:55a6170b404f 36
nexpaq 1:55a6170b404f 37 #if defined(MBEDTLS_CCM_C)
nexpaq 1:55a6170b404f 38
nexpaq 1:55a6170b404f 39 #include "mbedtls/ccm.h"
nexpaq 1:55a6170b404f 40
nexpaq 1:55a6170b404f 41 #include <string.h>
nexpaq 1:55a6170b404f 42
nexpaq 1:55a6170b404f 43 #if defined(MBEDTLS_SELF_TEST) && defined(MBEDTLS_AES_C)
nexpaq 1:55a6170b404f 44 #if defined(MBEDTLS_PLATFORM_C)
nexpaq 1:55a6170b404f 45 #include "mbedtls/platform.h"
nexpaq 1:55a6170b404f 46 #else
nexpaq 1:55a6170b404f 47 #include <stdio.h>
nexpaq 1:55a6170b404f 48 #define mbedtls_printf printf
nexpaq 1:55a6170b404f 49 #endif /* MBEDTLS_PLATFORM_C */
nexpaq 1:55a6170b404f 50 #endif /* MBEDTLS_SELF_TEST && MBEDTLS_AES_C */
nexpaq 1:55a6170b404f 51
nexpaq 1:55a6170b404f 52 /* Implementation that should never be optimized out by the compiler */
nexpaq 1:55a6170b404f 53 static void mbedtls_zeroize( void *v, size_t n ) {
nexpaq 1:55a6170b404f 54 volatile unsigned char *p = (unsigned char*)v; while( n-- ) *p++ = 0;
nexpaq 1:55a6170b404f 55 }
nexpaq 1:55a6170b404f 56
nexpaq 1:55a6170b404f 57 #define CCM_ENCRYPT 0
nexpaq 1:55a6170b404f 58 #define CCM_DECRYPT 1
nexpaq 1:55a6170b404f 59
nexpaq 1:55a6170b404f 60 /*
nexpaq 1:55a6170b404f 61 * Initialize context
nexpaq 1:55a6170b404f 62 */
nexpaq 1:55a6170b404f 63 void mbedtls_ccm_init( mbedtls_ccm_context *ctx )
nexpaq 1:55a6170b404f 64 {
nexpaq 1:55a6170b404f 65 memset( ctx, 0, sizeof( mbedtls_ccm_context ) );
nexpaq 1:55a6170b404f 66 }
nexpaq 1:55a6170b404f 67
nexpaq 1:55a6170b404f 68 int mbedtls_ccm_setkey( mbedtls_ccm_context *ctx,
nexpaq 1:55a6170b404f 69 mbedtls_cipher_id_t cipher,
nexpaq 1:55a6170b404f 70 const unsigned char *key,
nexpaq 1:55a6170b404f 71 unsigned int keybits )
nexpaq 1:55a6170b404f 72 {
nexpaq 1:55a6170b404f 73 int ret;
nexpaq 1:55a6170b404f 74 const mbedtls_cipher_info_t *cipher_info;
nexpaq 1:55a6170b404f 75
nexpaq 1:55a6170b404f 76 cipher_info = mbedtls_cipher_info_from_values( cipher, keybits, MBEDTLS_MODE_ECB );
nexpaq 1:55a6170b404f 77 if( cipher_info == NULL )
nexpaq 1:55a6170b404f 78 return( MBEDTLS_ERR_CCM_BAD_INPUT );
nexpaq 1:55a6170b404f 79
nexpaq 1:55a6170b404f 80 if( cipher_info->block_size != 16 )
nexpaq 1:55a6170b404f 81 return( MBEDTLS_ERR_CCM_BAD_INPUT );
nexpaq 1:55a6170b404f 82
nexpaq 1:55a6170b404f 83 mbedtls_cipher_free( &ctx->cipher_ctx );
nexpaq 1:55a6170b404f 84
nexpaq 1:55a6170b404f 85 if( ( ret = mbedtls_cipher_setup( &ctx->cipher_ctx, cipher_info ) ) != 0 )
nexpaq 1:55a6170b404f 86 return( ret );
nexpaq 1:55a6170b404f 87
nexpaq 1:55a6170b404f 88 if( ( ret = mbedtls_cipher_setkey( &ctx->cipher_ctx, key, keybits,
nexpaq 1:55a6170b404f 89 MBEDTLS_ENCRYPT ) ) != 0 )
nexpaq 1:55a6170b404f 90 {
nexpaq 1:55a6170b404f 91 return( ret );
nexpaq 1:55a6170b404f 92 }
nexpaq 1:55a6170b404f 93
nexpaq 1:55a6170b404f 94 return( 0 );
nexpaq 1:55a6170b404f 95 }
nexpaq 1:55a6170b404f 96
nexpaq 1:55a6170b404f 97 /*
nexpaq 1:55a6170b404f 98 * Free context
nexpaq 1:55a6170b404f 99 */
nexpaq 1:55a6170b404f 100 void mbedtls_ccm_free( mbedtls_ccm_context *ctx )
nexpaq 1:55a6170b404f 101 {
nexpaq 1:55a6170b404f 102 mbedtls_cipher_free( &ctx->cipher_ctx );
nexpaq 1:55a6170b404f 103 mbedtls_zeroize( ctx, sizeof( mbedtls_ccm_context ) );
nexpaq 1:55a6170b404f 104 }
nexpaq 1:55a6170b404f 105
nexpaq 1:55a6170b404f 106 /*
nexpaq 1:55a6170b404f 107 * Macros for common operations.
nexpaq 1:55a6170b404f 108 * Results in smaller compiled code than static inline functions.
nexpaq 1:55a6170b404f 109 */
nexpaq 1:55a6170b404f 110
nexpaq 1:55a6170b404f 111 /*
nexpaq 1:55a6170b404f 112 * Update the CBC-MAC state in y using a block in b
nexpaq 1:55a6170b404f 113 * (Always using b as the source helps the compiler optimise a bit better.)
nexpaq 1:55a6170b404f 114 */
nexpaq 1:55a6170b404f 115 #define UPDATE_CBC_MAC \
nexpaq 1:55a6170b404f 116 for( i = 0; i < 16; i++ ) \
nexpaq 1:55a6170b404f 117 y[i] ^= b[i]; \
nexpaq 1:55a6170b404f 118 \
nexpaq 1:55a6170b404f 119 if( ( ret = mbedtls_cipher_update( &ctx->cipher_ctx, y, 16, y, &olen ) ) != 0 ) \
nexpaq 1:55a6170b404f 120 return( ret );
nexpaq 1:55a6170b404f 121
nexpaq 1:55a6170b404f 122 /*
nexpaq 1:55a6170b404f 123 * Encrypt or decrypt a partial block with CTR
nexpaq 1:55a6170b404f 124 * Warning: using b for temporary storage! src and dst must not be b!
nexpaq 1:55a6170b404f 125 * This avoids allocating one more 16 bytes buffer while allowing src == dst.
nexpaq 1:55a6170b404f 126 */
nexpaq 1:55a6170b404f 127 #define CTR_CRYPT( dst, src, len ) \
nexpaq 1:55a6170b404f 128 if( ( ret = mbedtls_cipher_update( &ctx->cipher_ctx, ctr, 16, b, &olen ) ) != 0 ) \
nexpaq 1:55a6170b404f 129 return( ret ); \
nexpaq 1:55a6170b404f 130 \
nexpaq 1:55a6170b404f 131 for( i = 0; i < len; i++ ) \
nexpaq 1:55a6170b404f 132 dst[i] = src[i] ^ b[i];
nexpaq 1:55a6170b404f 133
nexpaq 1:55a6170b404f 134 /*
nexpaq 1:55a6170b404f 135 * Authenticated encryption or decryption
nexpaq 1:55a6170b404f 136 */
nexpaq 1:55a6170b404f 137 static int ccm_auth_crypt( mbedtls_ccm_context *ctx, int mode, size_t length,
nexpaq 1:55a6170b404f 138 const unsigned char *iv, size_t iv_len,
nexpaq 1:55a6170b404f 139 const unsigned char *add, size_t add_len,
nexpaq 1:55a6170b404f 140 const unsigned char *input, unsigned char *output,
nexpaq 1:55a6170b404f 141 unsigned char *tag, size_t tag_len )
nexpaq 1:55a6170b404f 142 {
nexpaq 1:55a6170b404f 143 int ret;
nexpaq 1:55a6170b404f 144 unsigned char i;
nexpaq 1:55a6170b404f 145 unsigned char q;
nexpaq 1:55a6170b404f 146 size_t len_left, olen;
nexpaq 1:55a6170b404f 147 unsigned char b[16];
nexpaq 1:55a6170b404f 148 unsigned char y[16];
nexpaq 1:55a6170b404f 149 unsigned char ctr[16];
nexpaq 1:55a6170b404f 150 const unsigned char *src;
nexpaq 1:55a6170b404f 151 unsigned char *dst;
nexpaq 1:55a6170b404f 152
nexpaq 1:55a6170b404f 153 /*
nexpaq 1:55a6170b404f 154 * Check length requirements: SP800-38C A.1
nexpaq 1:55a6170b404f 155 * Additional requirement: a < 2^16 - 2^8 to simplify the code.
nexpaq 1:55a6170b404f 156 * 'length' checked later (when writing it to the first block)
nexpaq 1:55a6170b404f 157 */
nexpaq 1:55a6170b404f 158 if( tag_len < 4 || tag_len > 16 || tag_len % 2 != 0 )
nexpaq 1:55a6170b404f 159 return( MBEDTLS_ERR_CCM_BAD_INPUT );
nexpaq 1:55a6170b404f 160
nexpaq 1:55a6170b404f 161 /* Also implies q is within bounds */
nexpaq 1:55a6170b404f 162 if( iv_len < 7 || iv_len > 13 )
nexpaq 1:55a6170b404f 163 return( MBEDTLS_ERR_CCM_BAD_INPUT );
nexpaq 1:55a6170b404f 164
nexpaq 1:55a6170b404f 165 if( add_len > 0xFF00 )
nexpaq 1:55a6170b404f 166 return( MBEDTLS_ERR_CCM_BAD_INPUT );
nexpaq 1:55a6170b404f 167
nexpaq 1:55a6170b404f 168 q = 16 - 1 - (unsigned char) iv_len;
nexpaq 1:55a6170b404f 169
nexpaq 1:55a6170b404f 170 /*
nexpaq 1:55a6170b404f 171 * First block B_0:
nexpaq 1:55a6170b404f 172 * 0 .. 0 flags
nexpaq 1:55a6170b404f 173 * 1 .. iv_len nonce (aka iv)
nexpaq 1:55a6170b404f 174 * iv_len+1 .. 15 length
nexpaq 1:55a6170b404f 175 *
nexpaq 1:55a6170b404f 176 * With flags as (bits):
nexpaq 1:55a6170b404f 177 * 7 0
nexpaq 1:55a6170b404f 178 * 6 add present?
nexpaq 1:55a6170b404f 179 * 5 .. 3 (t - 2) / 2
nexpaq 1:55a6170b404f 180 * 2 .. 0 q - 1
nexpaq 1:55a6170b404f 181 */
nexpaq 1:55a6170b404f 182 b[0] = 0;
nexpaq 1:55a6170b404f 183 b[0] |= ( add_len > 0 ) << 6;
nexpaq 1:55a6170b404f 184 b[0] |= ( ( tag_len - 2 ) / 2 ) << 3;
nexpaq 1:55a6170b404f 185 b[0] |= q - 1;
nexpaq 1:55a6170b404f 186
nexpaq 1:55a6170b404f 187 memcpy( b + 1, iv, iv_len );
nexpaq 1:55a6170b404f 188
nexpaq 1:55a6170b404f 189 for( i = 0, len_left = length; i < q; i++, len_left >>= 8 )
nexpaq 1:55a6170b404f 190 b[15-i] = (unsigned char)( len_left & 0xFF );
nexpaq 1:55a6170b404f 191
nexpaq 1:55a6170b404f 192 if( len_left > 0 )
nexpaq 1:55a6170b404f 193 return( MBEDTLS_ERR_CCM_BAD_INPUT );
nexpaq 1:55a6170b404f 194
nexpaq 1:55a6170b404f 195
nexpaq 1:55a6170b404f 196 /* Start CBC-MAC with first block */
nexpaq 1:55a6170b404f 197 memset( y, 0, 16 );
nexpaq 1:55a6170b404f 198 UPDATE_CBC_MAC;
nexpaq 1:55a6170b404f 199
nexpaq 1:55a6170b404f 200 /*
nexpaq 1:55a6170b404f 201 * If there is additional data, update CBC-MAC with
nexpaq 1:55a6170b404f 202 * add_len, add, 0 (padding to a block boundary)
nexpaq 1:55a6170b404f 203 */
nexpaq 1:55a6170b404f 204 if( add_len > 0 )
nexpaq 1:55a6170b404f 205 {
nexpaq 1:55a6170b404f 206 size_t use_len;
nexpaq 1:55a6170b404f 207 len_left = add_len;
nexpaq 1:55a6170b404f 208 src = add;
nexpaq 1:55a6170b404f 209
nexpaq 1:55a6170b404f 210 memset( b, 0, 16 );
nexpaq 1:55a6170b404f 211 b[0] = (unsigned char)( ( add_len >> 8 ) & 0xFF );
nexpaq 1:55a6170b404f 212 b[1] = (unsigned char)( ( add_len ) & 0xFF );
nexpaq 1:55a6170b404f 213
nexpaq 1:55a6170b404f 214 use_len = len_left < 16 - 2 ? len_left : 16 - 2;
nexpaq 1:55a6170b404f 215 memcpy( b + 2, src, use_len );
nexpaq 1:55a6170b404f 216 len_left -= use_len;
nexpaq 1:55a6170b404f 217 src += use_len;
nexpaq 1:55a6170b404f 218
nexpaq 1:55a6170b404f 219 UPDATE_CBC_MAC;
nexpaq 1:55a6170b404f 220
nexpaq 1:55a6170b404f 221 while( len_left > 0 )
nexpaq 1:55a6170b404f 222 {
nexpaq 1:55a6170b404f 223 use_len = len_left > 16 ? 16 : len_left;
nexpaq 1:55a6170b404f 224
nexpaq 1:55a6170b404f 225 memset( b, 0, 16 );
nexpaq 1:55a6170b404f 226 memcpy( b, src, use_len );
nexpaq 1:55a6170b404f 227 UPDATE_CBC_MAC;
nexpaq 1:55a6170b404f 228
nexpaq 1:55a6170b404f 229 len_left -= use_len;
nexpaq 1:55a6170b404f 230 src += use_len;
nexpaq 1:55a6170b404f 231 }
nexpaq 1:55a6170b404f 232 }
nexpaq 1:55a6170b404f 233
nexpaq 1:55a6170b404f 234 /*
nexpaq 1:55a6170b404f 235 * Prepare counter block for encryption:
nexpaq 1:55a6170b404f 236 * 0 .. 0 flags
nexpaq 1:55a6170b404f 237 * 1 .. iv_len nonce (aka iv)
nexpaq 1:55a6170b404f 238 * iv_len+1 .. 15 counter (initially 1)
nexpaq 1:55a6170b404f 239 *
nexpaq 1:55a6170b404f 240 * With flags as (bits):
nexpaq 1:55a6170b404f 241 * 7 .. 3 0
nexpaq 1:55a6170b404f 242 * 2 .. 0 q - 1
nexpaq 1:55a6170b404f 243 */
nexpaq 1:55a6170b404f 244 ctr[0] = q - 1;
nexpaq 1:55a6170b404f 245 memcpy( ctr + 1, iv, iv_len );
nexpaq 1:55a6170b404f 246 memset( ctr + 1 + iv_len, 0, q );
nexpaq 1:55a6170b404f 247 ctr[15] = 1;
nexpaq 1:55a6170b404f 248
nexpaq 1:55a6170b404f 249 /*
nexpaq 1:55a6170b404f 250 * Authenticate and {en,de}crypt the message.
nexpaq 1:55a6170b404f 251 *
nexpaq 1:55a6170b404f 252 * The only difference between encryption and decryption is
nexpaq 1:55a6170b404f 253 * the respective order of authentication and {en,de}cryption.
nexpaq 1:55a6170b404f 254 */
nexpaq 1:55a6170b404f 255 len_left = length;
nexpaq 1:55a6170b404f 256 src = input;
nexpaq 1:55a6170b404f 257 dst = output;
nexpaq 1:55a6170b404f 258
nexpaq 1:55a6170b404f 259 while( len_left > 0 )
nexpaq 1:55a6170b404f 260 {
nexpaq 1:55a6170b404f 261 size_t use_len = len_left > 16 ? 16 : len_left;
nexpaq 1:55a6170b404f 262
nexpaq 1:55a6170b404f 263 if( mode == CCM_ENCRYPT )
nexpaq 1:55a6170b404f 264 {
nexpaq 1:55a6170b404f 265 memset( b, 0, 16 );
nexpaq 1:55a6170b404f 266 memcpy( b, src, use_len );
nexpaq 1:55a6170b404f 267 UPDATE_CBC_MAC;
nexpaq 1:55a6170b404f 268 }
nexpaq 1:55a6170b404f 269
nexpaq 1:55a6170b404f 270 CTR_CRYPT( dst, src, use_len );
nexpaq 1:55a6170b404f 271
nexpaq 1:55a6170b404f 272 if( mode == CCM_DECRYPT )
nexpaq 1:55a6170b404f 273 {
nexpaq 1:55a6170b404f 274 memset( b, 0, 16 );
nexpaq 1:55a6170b404f 275 memcpy( b, dst, use_len );
nexpaq 1:55a6170b404f 276 UPDATE_CBC_MAC;
nexpaq 1:55a6170b404f 277 }
nexpaq 1:55a6170b404f 278
nexpaq 1:55a6170b404f 279 dst += use_len;
nexpaq 1:55a6170b404f 280 src += use_len;
nexpaq 1:55a6170b404f 281 len_left -= use_len;
nexpaq 1:55a6170b404f 282
nexpaq 1:55a6170b404f 283 /*
nexpaq 1:55a6170b404f 284 * Increment counter.
nexpaq 1:55a6170b404f 285 * No need to check for overflow thanks to the length check above.
nexpaq 1:55a6170b404f 286 */
nexpaq 1:55a6170b404f 287 for( i = 0; i < q; i++ )
nexpaq 1:55a6170b404f 288 if( ++ctr[15-i] != 0 )
nexpaq 1:55a6170b404f 289 break;
nexpaq 1:55a6170b404f 290 }
nexpaq 1:55a6170b404f 291
nexpaq 1:55a6170b404f 292 /*
nexpaq 1:55a6170b404f 293 * Authentication: reset counter and crypt/mask internal tag
nexpaq 1:55a6170b404f 294 */
nexpaq 1:55a6170b404f 295 for( i = 0; i < q; i++ )
nexpaq 1:55a6170b404f 296 ctr[15-i] = 0;
nexpaq 1:55a6170b404f 297
nexpaq 1:55a6170b404f 298 CTR_CRYPT( y, y, 16 );
nexpaq 1:55a6170b404f 299 memcpy( tag, y, tag_len );
nexpaq 1:55a6170b404f 300
nexpaq 1:55a6170b404f 301 return( 0 );
nexpaq 1:55a6170b404f 302 }
nexpaq 1:55a6170b404f 303
nexpaq 1:55a6170b404f 304 /*
nexpaq 1:55a6170b404f 305 * Authenticated encryption
nexpaq 1:55a6170b404f 306 */
nexpaq 1:55a6170b404f 307 int mbedtls_ccm_encrypt_and_tag( mbedtls_ccm_context *ctx, size_t length,
nexpaq 1:55a6170b404f 308 const unsigned char *iv, size_t iv_len,
nexpaq 1:55a6170b404f 309 const unsigned char *add, size_t add_len,
nexpaq 1:55a6170b404f 310 const unsigned char *input, unsigned char *output,
nexpaq 1:55a6170b404f 311 unsigned char *tag, size_t tag_len )
nexpaq 1:55a6170b404f 312 {
nexpaq 1:55a6170b404f 313 return( ccm_auth_crypt( ctx, CCM_ENCRYPT, length, iv, iv_len,
nexpaq 1:55a6170b404f 314 add, add_len, input, output, tag, tag_len ) );
nexpaq 1:55a6170b404f 315 }
nexpaq 1:55a6170b404f 316
nexpaq 1:55a6170b404f 317 /*
nexpaq 1:55a6170b404f 318 * Authenticated decryption
nexpaq 1:55a6170b404f 319 */
nexpaq 1:55a6170b404f 320 int mbedtls_ccm_auth_decrypt( mbedtls_ccm_context *ctx, size_t length,
nexpaq 1:55a6170b404f 321 const unsigned char *iv, size_t iv_len,
nexpaq 1:55a6170b404f 322 const unsigned char *add, size_t add_len,
nexpaq 1:55a6170b404f 323 const unsigned char *input, unsigned char *output,
nexpaq 1:55a6170b404f 324 const unsigned char *tag, size_t tag_len )
nexpaq 1:55a6170b404f 325 {
nexpaq 1:55a6170b404f 326 int ret;
nexpaq 1:55a6170b404f 327 unsigned char check_tag[16];
nexpaq 1:55a6170b404f 328 unsigned char i;
nexpaq 1:55a6170b404f 329 int diff;
nexpaq 1:55a6170b404f 330
nexpaq 1:55a6170b404f 331 if( ( ret = ccm_auth_crypt( ctx, CCM_DECRYPT, length,
nexpaq 1:55a6170b404f 332 iv, iv_len, add, add_len,
nexpaq 1:55a6170b404f 333 input, output, check_tag, tag_len ) ) != 0 )
nexpaq 1:55a6170b404f 334 {
nexpaq 1:55a6170b404f 335 return( ret );
nexpaq 1:55a6170b404f 336 }
nexpaq 1:55a6170b404f 337
nexpaq 1:55a6170b404f 338 /* Check tag in "constant-time" */
nexpaq 1:55a6170b404f 339 for( diff = 0, i = 0; i < tag_len; i++ )
nexpaq 1:55a6170b404f 340 diff |= tag[i] ^ check_tag[i];
nexpaq 1:55a6170b404f 341
nexpaq 1:55a6170b404f 342 if( diff != 0 )
nexpaq 1:55a6170b404f 343 {
nexpaq 1:55a6170b404f 344 mbedtls_zeroize( output, length );
nexpaq 1:55a6170b404f 345 return( MBEDTLS_ERR_CCM_AUTH_FAILED );
nexpaq 1:55a6170b404f 346 }
nexpaq 1:55a6170b404f 347
nexpaq 1:55a6170b404f 348 return( 0 );
nexpaq 1:55a6170b404f 349 }
nexpaq 1:55a6170b404f 350
nexpaq 1:55a6170b404f 351
nexpaq 1:55a6170b404f 352 #if defined(MBEDTLS_SELF_TEST) && defined(MBEDTLS_AES_C)
nexpaq 1:55a6170b404f 353 /*
nexpaq 1:55a6170b404f 354 * Examples 1 to 3 from SP800-38C Appendix C
nexpaq 1:55a6170b404f 355 */
nexpaq 1:55a6170b404f 356
nexpaq 1:55a6170b404f 357 #define NB_TESTS 3
nexpaq 1:55a6170b404f 358
nexpaq 1:55a6170b404f 359 /*
nexpaq 1:55a6170b404f 360 * The data is the same for all tests, only the used length changes
nexpaq 1:55a6170b404f 361 */
nexpaq 1:55a6170b404f 362 static const unsigned char key[] = {
nexpaq 1:55a6170b404f 363 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
nexpaq 1:55a6170b404f 364 0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f
nexpaq 1:55a6170b404f 365 };
nexpaq 1:55a6170b404f 366
nexpaq 1:55a6170b404f 367 static const unsigned char iv[] = {
nexpaq 1:55a6170b404f 368 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
nexpaq 1:55a6170b404f 369 0x18, 0x19, 0x1a, 0x1b
nexpaq 1:55a6170b404f 370 };
nexpaq 1:55a6170b404f 371
nexpaq 1:55a6170b404f 372 static const unsigned char ad[] = {
nexpaq 1:55a6170b404f 373 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
nexpaq 1:55a6170b404f 374 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
nexpaq 1:55a6170b404f 375 0x10, 0x11, 0x12, 0x13
nexpaq 1:55a6170b404f 376 };
nexpaq 1:55a6170b404f 377
nexpaq 1:55a6170b404f 378 static const unsigned char msg[] = {
nexpaq 1:55a6170b404f 379 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
nexpaq 1:55a6170b404f 380 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
nexpaq 1:55a6170b404f 381 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
nexpaq 1:55a6170b404f 382 };
nexpaq 1:55a6170b404f 383
nexpaq 1:55a6170b404f 384 static const size_t iv_len [NB_TESTS] = { 7, 8, 12 };
nexpaq 1:55a6170b404f 385 static const size_t add_len[NB_TESTS] = { 8, 16, 20 };
nexpaq 1:55a6170b404f 386 static const size_t msg_len[NB_TESTS] = { 4, 16, 24 };
nexpaq 1:55a6170b404f 387 static const size_t tag_len[NB_TESTS] = { 4, 6, 8 };
nexpaq 1:55a6170b404f 388
nexpaq 1:55a6170b404f 389 static const unsigned char res[NB_TESTS][32] = {
nexpaq 1:55a6170b404f 390 { 0x71, 0x62, 0x01, 0x5b, 0x4d, 0xac, 0x25, 0x5d },
nexpaq 1:55a6170b404f 391 { 0xd2, 0xa1, 0xf0, 0xe0, 0x51, 0xea, 0x5f, 0x62,
nexpaq 1:55a6170b404f 392 0x08, 0x1a, 0x77, 0x92, 0x07, 0x3d, 0x59, 0x3d,
nexpaq 1:55a6170b404f 393 0x1f, 0xc6, 0x4f, 0xbf, 0xac, 0xcd },
nexpaq 1:55a6170b404f 394 { 0xe3, 0xb2, 0x01, 0xa9, 0xf5, 0xb7, 0x1a, 0x7a,
nexpaq 1:55a6170b404f 395 0x9b, 0x1c, 0xea, 0xec, 0xcd, 0x97, 0xe7, 0x0b,
nexpaq 1:55a6170b404f 396 0x61, 0x76, 0xaa, 0xd9, 0xa4, 0x42, 0x8a, 0xa5,
nexpaq 1:55a6170b404f 397 0x48, 0x43, 0x92, 0xfb, 0xc1, 0xb0, 0x99, 0x51 }
nexpaq 1:55a6170b404f 398 };
nexpaq 1:55a6170b404f 399
nexpaq 1:55a6170b404f 400 int mbedtls_ccm_self_test( int verbose )
nexpaq 1:55a6170b404f 401 {
nexpaq 1:55a6170b404f 402 mbedtls_ccm_context ctx;
nexpaq 1:55a6170b404f 403 unsigned char out[32];
nexpaq 1:55a6170b404f 404 size_t i;
nexpaq 1:55a6170b404f 405 int ret;
nexpaq 1:55a6170b404f 406
nexpaq 1:55a6170b404f 407 mbedtls_ccm_init( &ctx );
nexpaq 1:55a6170b404f 408
nexpaq 1:55a6170b404f 409 if( mbedtls_ccm_setkey( &ctx, MBEDTLS_CIPHER_ID_AES, key, 8 * sizeof key ) != 0 )
nexpaq 1:55a6170b404f 410 {
nexpaq 1:55a6170b404f 411 if( verbose != 0 )
nexpaq 1:55a6170b404f 412 mbedtls_printf( " CCM: setup failed" );
nexpaq 1:55a6170b404f 413
nexpaq 1:55a6170b404f 414 return( 1 );
nexpaq 1:55a6170b404f 415 }
nexpaq 1:55a6170b404f 416
nexpaq 1:55a6170b404f 417 for( i = 0; i < NB_TESTS; i++ )
nexpaq 1:55a6170b404f 418 {
nexpaq 1:55a6170b404f 419 if( verbose != 0 )
nexpaq 1:55a6170b404f 420 mbedtls_printf( " CCM-AES #%u: ", (unsigned int) i + 1 );
nexpaq 1:55a6170b404f 421
nexpaq 1:55a6170b404f 422 ret = mbedtls_ccm_encrypt_and_tag( &ctx, msg_len[i],
nexpaq 1:55a6170b404f 423 iv, iv_len[i], ad, add_len[i],
nexpaq 1:55a6170b404f 424 msg, out,
nexpaq 1:55a6170b404f 425 out + msg_len[i], tag_len[i] );
nexpaq 1:55a6170b404f 426
nexpaq 1:55a6170b404f 427 if( ret != 0 ||
nexpaq 1:55a6170b404f 428 memcmp( out, res[i], msg_len[i] + tag_len[i] ) != 0 )
nexpaq 1:55a6170b404f 429 {
nexpaq 1:55a6170b404f 430 if( verbose != 0 )
nexpaq 1:55a6170b404f 431 mbedtls_printf( "failed\n" );
nexpaq 1:55a6170b404f 432
nexpaq 1:55a6170b404f 433 return( 1 );
nexpaq 1:55a6170b404f 434 }
nexpaq 1:55a6170b404f 435
nexpaq 1:55a6170b404f 436 ret = mbedtls_ccm_auth_decrypt( &ctx, msg_len[i],
nexpaq 1:55a6170b404f 437 iv, iv_len[i], ad, add_len[i],
nexpaq 1:55a6170b404f 438 res[i], out,
nexpaq 1:55a6170b404f 439 res[i] + msg_len[i], tag_len[i] );
nexpaq 1:55a6170b404f 440
nexpaq 1:55a6170b404f 441 if( ret != 0 ||
nexpaq 1:55a6170b404f 442 memcmp( out, msg, msg_len[i] ) != 0 )
nexpaq 1:55a6170b404f 443 {
nexpaq 1:55a6170b404f 444 if( verbose != 0 )
nexpaq 1:55a6170b404f 445 mbedtls_printf( "failed\n" );
nexpaq 1:55a6170b404f 446
nexpaq 1:55a6170b404f 447 return( 1 );
nexpaq 1:55a6170b404f 448 }
nexpaq 1:55a6170b404f 449
nexpaq 1:55a6170b404f 450 if( verbose != 0 )
nexpaq 1:55a6170b404f 451 mbedtls_printf( "passed\n" );
nexpaq 1:55a6170b404f 452 }
nexpaq 1:55a6170b404f 453
nexpaq 1:55a6170b404f 454 mbedtls_ccm_free( &ctx );
nexpaq 1:55a6170b404f 455
nexpaq 1:55a6170b404f 456 if( verbose != 0 )
nexpaq 1:55a6170b404f 457 mbedtls_printf( "\n" );
nexpaq 1:55a6170b404f 458
nexpaq 1:55a6170b404f 459 return( 0 );
nexpaq 1:55a6170b404f 460 }
nexpaq 1:55a6170b404f 461
nexpaq 1:55a6170b404f 462 #endif /* MBEDTLS_SELF_TEST && MBEDTLS_AES_C */
nexpaq 1:55a6170b404f 463
nexpaq 1:55a6170b404f 464 #endif /* MBEDTLS_CCM_C */