Magnificent7 / Hackathon

Includes library modifications to allow access to AIN_4 (AIN_0 / 5)

mbd_os/features/mbedtls/src/ccm.c@0:eafc3fd41f75, 2016-09-20 (annotated)

Committer:
bryantaylor
Date:
Tue Sep 20 21:26:12 2016 +0000
Revision:
0:eafc3fd41f75
hackathon

Who changed what in which revision?

UserRevisionLine numberNew contents of line
bryantaylor 0:eafc3fd41f75 1 /*
bryantaylor 0:eafc3fd41f75 2 * NIST SP800-38C compliant CCM implementation
bryantaylor 0:eafc3fd41f75 3 *
bryantaylor 0:eafc3fd41f75 4 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
bryantaylor 0:eafc3fd41f75 5 * SPDX-License-Identifier: Apache-2.0
bryantaylor 0:eafc3fd41f75 6 *
bryantaylor 0:eafc3fd41f75 7 * Licensed under the Apache License, Version 2.0 (the "License"); you may
bryantaylor 0:eafc3fd41f75 8 * not use this file except in compliance with the License.
bryantaylor 0:eafc3fd41f75 9 * You may obtain a copy of the License at
bryantaylor 0:eafc3fd41f75 10 *
bryantaylor 0:eafc3fd41f75 11 * http://www.apache.org/licenses/LICENSE-2.0
bryantaylor 0:eafc3fd41f75 12 *
bryantaylor 0:eafc3fd41f75 13 * Unless required by applicable law or agreed to in writing, software
bryantaylor 0:eafc3fd41f75 14 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
bryantaylor 0:eafc3fd41f75 15 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
bryantaylor 0:eafc3fd41f75 16 * See the License for the specific language governing permissions and
bryantaylor 0:eafc3fd41f75 17 * limitations under the License.
bryantaylor 0:eafc3fd41f75 18 *
bryantaylor 0:eafc3fd41f75 19 * This file is part of mbed TLS (https://tls.mbed.org)
bryantaylor 0:eafc3fd41f75 20 */
bryantaylor 0:eafc3fd41f75 21
bryantaylor 0:eafc3fd41f75 22 /*
bryantaylor 0:eafc3fd41f75 23 * Definition of CCM:
bryantaylor 0:eafc3fd41f75 24 * http://csrc.nist.gov/publications/nistpubs/800-38C/SP800-38C_updated-July20_2007.pdf
bryantaylor 0:eafc3fd41f75 25 * RFC 3610 "Counter with CBC-MAC (CCM)"
bryantaylor 0:eafc3fd41f75 26 *
bryantaylor 0:eafc3fd41f75 27 * Related:
bryantaylor 0:eafc3fd41f75 28 * RFC 5116 "An Interface and Algorithms for Authenticated Encryption"
bryantaylor 0:eafc3fd41f75 29 */
bryantaylor 0:eafc3fd41f75 30
bryantaylor 0:eafc3fd41f75 31 #if !defined(MBEDTLS_CONFIG_FILE)
bryantaylor 0:eafc3fd41f75 32 #include "mbedtls/config.h"
bryantaylor 0:eafc3fd41f75 33 #else
bryantaylor 0:eafc3fd41f75 34 #include MBEDTLS_CONFIG_FILE
bryantaylor 0:eafc3fd41f75 35 #endif
bryantaylor 0:eafc3fd41f75 36
bryantaylor 0:eafc3fd41f75 37 #if defined(MBEDTLS_CCM_C)
bryantaylor 0:eafc3fd41f75 38
bryantaylor 0:eafc3fd41f75 39 #include "mbedtls/ccm.h"
bryantaylor 0:eafc3fd41f75 40
bryantaylor 0:eafc3fd41f75 41 #include <string.h>
bryantaylor 0:eafc3fd41f75 42
bryantaylor 0:eafc3fd41f75 43 #if defined(MBEDTLS_SELF_TEST) && defined(MBEDTLS_AES_C)
bryantaylor 0:eafc3fd41f75 44 #if defined(MBEDTLS_PLATFORM_C)
bryantaylor 0:eafc3fd41f75 45 #include "mbedtls/platform.h"
bryantaylor 0:eafc3fd41f75 46 #else
bryantaylor 0:eafc3fd41f75 47 #include <stdio.h>
bryantaylor 0:eafc3fd41f75 48 #define mbedtls_printf printf
bryantaylor 0:eafc3fd41f75 49 #endif /* MBEDTLS_PLATFORM_C */
bryantaylor 0:eafc3fd41f75 50 #endif /* MBEDTLS_SELF_TEST && MBEDTLS_AES_C */
bryantaylor 0:eafc3fd41f75 51
bryantaylor 0:eafc3fd41f75 52 /* Implementation that should never be optimized out by the compiler */
bryantaylor 0:eafc3fd41f75 53 static void mbedtls_zeroize( void *v, size_t n ) {
bryantaylor 0:eafc3fd41f75 54 volatile unsigned char *p = (unsigned char*)v; while( n-- ) *p++ = 0;
bryantaylor 0:eafc3fd41f75 55 }
bryantaylor 0:eafc3fd41f75 56
bryantaylor 0:eafc3fd41f75 57 #define CCM_ENCRYPT 0
bryantaylor 0:eafc3fd41f75 58 #define CCM_DECRYPT 1
bryantaylor 0:eafc3fd41f75 59
bryantaylor 0:eafc3fd41f75 60 /*
bryantaylor 0:eafc3fd41f75 61 * Initialize context
bryantaylor 0:eafc3fd41f75 62 */
bryantaylor 0:eafc3fd41f75 63 void mbedtls_ccm_init( mbedtls_ccm_context *ctx )
bryantaylor 0:eafc3fd41f75 64 {
bryantaylor 0:eafc3fd41f75 65 memset( ctx, 0, sizeof( mbedtls_ccm_context ) );
bryantaylor 0:eafc3fd41f75 66 }
bryantaylor 0:eafc3fd41f75 67
bryantaylor 0:eafc3fd41f75 68 int mbedtls_ccm_setkey( mbedtls_ccm_context *ctx,
bryantaylor 0:eafc3fd41f75 69 mbedtls_cipher_id_t cipher,
bryantaylor 0:eafc3fd41f75 70 const unsigned char *key,
bryantaylor 0:eafc3fd41f75 71 unsigned int keybits )
bryantaylor 0:eafc3fd41f75 72 {
bryantaylor 0:eafc3fd41f75 73 int ret;
bryantaylor 0:eafc3fd41f75 74 const mbedtls_cipher_info_t *cipher_info;
bryantaylor 0:eafc3fd41f75 75
bryantaylor 0:eafc3fd41f75 76 cipher_info = mbedtls_cipher_info_from_values( cipher, keybits, MBEDTLS_MODE_ECB );
bryantaylor 0:eafc3fd41f75 77 if( cipher_info == NULL )
bryantaylor 0:eafc3fd41f75 78 return( MBEDTLS_ERR_CCM_BAD_INPUT );
bryantaylor 0:eafc3fd41f75 79
bryantaylor 0:eafc3fd41f75 80 if( cipher_info->block_size != 16 )
bryantaylor 0:eafc3fd41f75 81 return( MBEDTLS_ERR_CCM_BAD_INPUT );
bryantaylor 0:eafc3fd41f75 82
bryantaylor 0:eafc3fd41f75 83 mbedtls_cipher_free( &ctx->cipher_ctx );
bryantaylor 0:eafc3fd41f75 84
bryantaylor 0:eafc3fd41f75 85 if( ( ret = mbedtls_cipher_setup( &ctx->cipher_ctx, cipher_info ) ) != 0 )
bryantaylor 0:eafc3fd41f75 86 return( ret );
bryantaylor 0:eafc3fd41f75 87
bryantaylor 0:eafc3fd41f75 88 if( ( ret = mbedtls_cipher_setkey( &ctx->cipher_ctx, key, keybits,
bryantaylor 0:eafc3fd41f75 89 MBEDTLS_ENCRYPT ) ) != 0 )
bryantaylor 0:eafc3fd41f75 90 {
bryantaylor 0:eafc3fd41f75 91 return( ret );
bryantaylor 0:eafc3fd41f75 92 }
bryantaylor 0:eafc3fd41f75 93
bryantaylor 0:eafc3fd41f75 94 return( 0 );
bryantaylor 0:eafc3fd41f75 95 }
bryantaylor 0:eafc3fd41f75 96
bryantaylor 0:eafc3fd41f75 97 /*
bryantaylor 0:eafc3fd41f75 98 * Free context
bryantaylor 0:eafc3fd41f75 99 */
bryantaylor 0:eafc3fd41f75 100 void mbedtls_ccm_free( mbedtls_ccm_context *ctx )
bryantaylor 0:eafc3fd41f75 101 {
bryantaylor 0:eafc3fd41f75 102 mbedtls_cipher_free( &ctx->cipher_ctx );
bryantaylor 0:eafc3fd41f75 103 mbedtls_zeroize( ctx, sizeof( mbedtls_ccm_context ) );
bryantaylor 0:eafc3fd41f75 104 }
bryantaylor 0:eafc3fd41f75 105
bryantaylor 0:eafc3fd41f75 106 /*
bryantaylor 0:eafc3fd41f75 107 * Macros for common operations.
bryantaylor 0:eafc3fd41f75 108 * Results in smaller compiled code than static inline functions.
bryantaylor 0:eafc3fd41f75 109 */
bryantaylor 0:eafc3fd41f75 110
bryantaylor 0:eafc3fd41f75 111 /*
bryantaylor 0:eafc3fd41f75 112 * Update the CBC-MAC state in y using a block in b
bryantaylor 0:eafc3fd41f75 113 * (Always using b as the source helps the compiler optimise a bit better.)
bryantaylor 0:eafc3fd41f75 114 */
bryantaylor 0:eafc3fd41f75 115 #define UPDATE_CBC_MAC \
bryantaylor 0:eafc3fd41f75 116 for( i = 0; i < 16; i++ ) \
bryantaylor 0:eafc3fd41f75 117 y[i] ^= b[i]; \
bryantaylor 0:eafc3fd41f75 118 \
bryantaylor 0:eafc3fd41f75 119 if( ( ret = mbedtls_cipher_update( &ctx->cipher_ctx, y, 16, y, &olen ) ) != 0 ) \
bryantaylor 0:eafc3fd41f75 120 return( ret );
bryantaylor 0:eafc3fd41f75 121
bryantaylor 0:eafc3fd41f75 122 /*
bryantaylor 0:eafc3fd41f75 123 * Encrypt or decrypt a partial block with CTR
bryantaylor 0:eafc3fd41f75 124 * Warning: using b for temporary storage! src and dst must not be b!
bryantaylor 0:eafc3fd41f75 125 * This avoids allocating one more 16 bytes buffer while allowing src == dst.
bryantaylor 0:eafc3fd41f75 126 */
bryantaylor 0:eafc3fd41f75 127 #define CTR_CRYPT( dst, src, len ) \
bryantaylor 0:eafc3fd41f75 128 if( ( ret = mbedtls_cipher_update( &ctx->cipher_ctx, ctr, 16, b, &olen ) ) != 0 ) \
bryantaylor 0:eafc3fd41f75 129 return( ret ); \
bryantaylor 0:eafc3fd41f75 130 \
bryantaylor 0:eafc3fd41f75 131 for( i = 0; i < len; i++ ) \
bryantaylor 0:eafc3fd41f75 132 dst[i] = src[i] ^ b[i];
bryantaylor 0:eafc3fd41f75 133
bryantaylor 0:eafc3fd41f75 134 /*
bryantaylor 0:eafc3fd41f75 135 * Authenticated encryption or decryption
bryantaylor 0:eafc3fd41f75 136 */
bryantaylor 0:eafc3fd41f75 137 static int ccm_auth_crypt( mbedtls_ccm_context *ctx, int mode, size_t length,
bryantaylor 0:eafc3fd41f75 138 const unsigned char *iv, size_t iv_len,
bryantaylor 0:eafc3fd41f75 139 const unsigned char *add, size_t add_len,
bryantaylor 0:eafc3fd41f75 140 const unsigned char *input, unsigned char *output,
bryantaylor 0:eafc3fd41f75 141 unsigned char *tag, size_t tag_len )
bryantaylor 0:eafc3fd41f75 142 {
bryantaylor 0:eafc3fd41f75 143 int ret;
bryantaylor 0:eafc3fd41f75 144 unsigned char i;
bryantaylor 0:eafc3fd41f75 145 unsigned char q;
bryantaylor 0:eafc3fd41f75 146 size_t len_left, olen;
bryantaylor 0:eafc3fd41f75 147 unsigned char b[16];
bryantaylor 0:eafc3fd41f75 148 unsigned char y[16];
bryantaylor 0:eafc3fd41f75 149 unsigned char ctr[16];
bryantaylor 0:eafc3fd41f75 150 const unsigned char *src;
bryantaylor 0:eafc3fd41f75 151 unsigned char *dst;
bryantaylor 0:eafc3fd41f75 152
bryantaylor 0:eafc3fd41f75 153 /*
bryantaylor 0:eafc3fd41f75 154 * Check length requirements: SP800-38C A.1
bryantaylor 0:eafc3fd41f75 155 * Additional requirement: a < 2^16 - 2^8 to simplify the code.
bryantaylor 0:eafc3fd41f75 156 * 'length' checked later (when writing it to the first block)
bryantaylor 0:eafc3fd41f75 157 */
bryantaylor 0:eafc3fd41f75 158 if( tag_len < 4 || tag_len > 16 || tag_len % 2 != 0 )
bryantaylor 0:eafc3fd41f75 159 return( MBEDTLS_ERR_CCM_BAD_INPUT );
bryantaylor 0:eafc3fd41f75 160
bryantaylor 0:eafc3fd41f75 161 /* Also implies q is within bounds */
bryantaylor 0:eafc3fd41f75 162 if( iv_len < 7 || iv_len > 13 )
bryantaylor 0:eafc3fd41f75 163 return( MBEDTLS_ERR_CCM_BAD_INPUT );
bryantaylor 0:eafc3fd41f75 164
bryantaylor 0:eafc3fd41f75 165 if( add_len > 0xFF00 )
bryantaylor 0:eafc3fd41f75 166 return( MBEDTLS_ERR_CCM_BAD_INPUT );
bryantaylor 0:eafc3fd41f75 167
bryantaylor 0:eafc3fd41f75 168 q = 16 - 1 - (unsigned char) iv_len;
bryantaylor 0:eafc3fd41f75 169
bryantaylor 0:eafc3fd41f75 170 /*
bryantaylor 0:eafc3fd41f75 171 * First block B_0:
bryantaylor 0:eafc3fd41f75 172 * 0 .. 0 flags
bryantaylor 0:eafc3fd41f75 173 * 1 .. iv_len nonce (aka iv)
bryantaylor 0:eafc3fd41f75 174 * iv_len+1 .. 15 length
bryantaylor 0:eafc3fd41f75 175 *
bryantaylor 0:eafc3fd41f75 176 * With flags as (bits):
bryantaylor 0:eafc3fd41f75 177 * 7 0
bryantaylor 0:eafc3fd41f75 178 * 6 add present?
bryantaylor 0:eafc3fd41f75 179 * 5 .. 3 (t - 2) / 2
bryantaylor 0:eafc3fd41f75 180 * 2 .. 0 q - 1
bryantaylor 0:eafc3fd41f75 181 */
bryantaylor 0:eafc3fd41f75 182 b[0] = 0;
bryantaylor 0:eafc3fd41f75 183 b[0] |= ( add_len > 0 ) << 6;
bryantaylor 0:eafc3fd41f75 184 b[0] |= ( ( tag_len - 2 ) / 2 ) << 3;
bryantaylor 0:eafc3fd41f75 185 b[0] |= q - 1;
bryantaylor 0:eafc3fd41f75 186
bryantaylor 0:eafc3fd41f75 187 memcpy( b + 1, iv, iv_len );
bryantaylor 0:eafc3fd41f75 188
bryantaylor 0:eafc3fd41f75 189 for( i = 0, len_left = length; i < q; i++, len_left >>= 8 )
bryantaylor 0:eafc3fd41f75 190 b[15-i] = (unsigned char)( len_left & 0xFF );
bryantaylor 0:eafc3fd41f75 191
bryantaylor 0:eafc3fd41f75 192 if( len_left > 0 )
bryantaylor 0:eafc3fd41f75 193 return( MBEDTLS_ERR_CCM_BAD_INPUT );
bryantaylor 0:eafc3fd41f75 194
bryantaylor 0:eafc3fd41f75 195
bryantaylor 0:eafc3fd41f75 196 /* Start CBC-MAC with first block */
bryantaylor 0:eafc3fd41f75 197 memset( y, 0, 16 );
bryantaylor 0:eafc3fd41f75 198 UPDATE_CBC_MAC;
bryantaylor 0:eafc3fd41f75 199
bryantaylor 0:eafc3fd41f75 200 /*
bryantaylor 0:eafc3fd41f75 201 * If there is additional data, update CBC-MAC with
bryantaylor 0:eafc3fd41f75 202 * add_len, add, 0 (padding to a block boundary)
bryantaylor 0:eafc3fd41f75 203 */
bryantaylor 0:eafc3fd41f75 204 if( add_len > 0 )
bryantaylor 0:eafc3fd41f75 205 {
bryantaylor 0:eafc3fd41f75 206 size_t use_len;
bryantaylor 0:eafc3fd41f75 207 len_left = add_len;
bryantaylor 0:eafc3fd41f75 208 src = add;
bryantaylor 0:eafc3fd41f75 209
bryantaylor 0:eafc3fd41f75 210 memset( b, 0, 16 );
bryantaylor 0:eafc3fd41f75 211 b[0] = (unsigned char)( ( add_len >> 8 ) & 0xFF );
bryantaylor 0:eafc3fd41f75 212 b[1] = (unsigned char)( ( add_len ) & 0xFF );
bryantaylor 0:eafc3fd41f75 213
bryantaylor 0:eafc3fd41f75 214 use_len = len_left < 16 - 2 ? len_left : 16 - 2;
bryantaylor 0:eafc3fd41f75 215 memcpy( b + 2, src, use_len );
bryantaylor 0:eafc3fd41f75 216 len_left -= use_len;
bryantaylor 0:eafc3fd41f75 217 src += use_len;
bryantaylor 0:eafc3fd41f75 218
bryantaylor 0:eafc3fd41f75 219 UPDATE_CBC_MAC;
bryantaylor 0:eafc3fd41f75 220
bryantaylor 0:eafc3fd41f75 221 while( len_left > 0 )
bryantaylor 0:eafc3fd41f75 222 {
bryantaylor 0:eafc3fd41f75 223 use_len = len_left > 16 ? 16 : len_left;
bryantaylor 0:eafc3fd41f75 224
bryantaylor 0:eafc3fd41f75 225 memset( b, 0, 16 );
bryantaylor 0:eafc3fd41f75 226 memcpy( b, src, use_len );
bryantaylor 0:eafc3fd41f75 227 UPDATE_CBC_MAC;
bryantaylor 0:eafc3fd41f75 228
bryantaylor 0:eafc3fd41f75 229 len_left -= use_len;
bryantaylor 0:eafc3fd41f75 230 src += use_len;
bryantaylor 0:eafc3fd41f75 231 }
bryantaylor 0:eafc3fd41f75 232 }
bryantaylor 0:eafc3fd41f75 233
bryantaylor 0:eafc3fd41f75 234 /*
bryantaylor 0:eafc3fd41f75 235 * Prepare counter block for encryption:
bryantaylor 0:eafc3fd41f75 236 * 0 .. 0 flags
bryantaylor 0:eafc3fd41f75 237 * 1 .. iv_len nonce (aka iv)
bryantaylor 0:eafc3fd41f75 238 * iv_len+1 .. 15 counter (initially 1)
bryantaylor 0:eafc3fd41f75 239 *
bryantaylor 0:eafc3fd41f75 240 * With flags as (bits):
bryantaylor 0:eafc3fd41f75 241 * 7 .. 3 0
bryantaylor 0:eafc3fd41f75 242 * 2 .. 0 q - 1
bryantaylor 0:eafc3fd41f75 243 */
bryantaylor 0:eafc3fd41f75 244 ctr[0] = q - 1;
bryantaylor 0:eafc3fd41f75 245 memcpy( ctr + 1, iv, iv_len );
bryantaylor 0:eafc3fd41f75 246 memset( ctr + 1 + iv_len, 0, q );
bryantaylor 0:eafc3fd41f75 247 ctr[15] = 1;
bryantaylor 0:eafc3fd41f75 248
bryantaylor 0:eafc3fd41f75 249 /*
bryantaylor 0:eafc3fd41f75 250 * Authenticate and {en,de}crypt the message.
bryantaylor 0:eafc3fd41f75 251 *
bryantaylor 0:eafc3fd41f75 252 * The only difference between encryption and decryption is
bryantaylor 0:eafc3fd41f75 253 * the respective order of authentication and {en,de}cryption.
bryantaylor 0:eafc3fd41f75 254 */
bryantaylor 0:eafc3fd41f75 255 len_left = length;
bryantaylor 0:eafc3fd41f75 256 src = input;
bryantaylor 0:eafc3fd41f75 257 dst = output;
bryantaylor 0:eafc3fd41f75 258
bryantaylor 0:eafc3fd41f75 259 while( len_left > 0 )
bryantaylor 0:eafc3fd41f75 260 {
bryantaylor 0:eafc3fd41f75 261 size_t use_len = len_left > 16 ? 16 : len_left;
bryantaylor 0:eafc3fd41f75 262
bryantaylor 0:eafc3fd41f75 263 if( mode == CCM_ENCRYPT )
bryantaylor 0:eafc3fd41f75 264 {
bryantaylor 0:eafc3fd41f75 265 memset( b, 0, 16 );
bryantaylor 0:eafc3fd41f75 266 memcpy( b, src, use_len );
bryantaylor 0:eafc3fd41f75 267 UPDATE_CBC_MAC;
bryantaylor 0:eafc3fd41f75 268 }
bryantaylor 0:eafc3fd41f75 269
bryantaylor 0:eafc3fd41f75 270 CTR_CRYPT( dst, src, use_len );
bryantaylor 0:eafc3fd41f75 271
bryantaylor 0:eafc3fd41f75 272 if( mode == CCM_DECRYPT )
bryantaylor 0:eafc3fd41f75 273 {
bryantaylor 0:eafc3fd41f75 274 memset( b, 0, 16 );
bryantaylor 0:eafc3fd41f75 275 memcpy( b, dst, use_len );
bryantaylor 0:eafc3fd41f75 276 UPDATE_CBC_MAC;
bryantaylor 0:eafc3fd41f75 277 }
bryantaylor 0:eafc3fd41f75 278
bryantaylor 0:eafc3fd41f75 279 dst += use_len;
bryantaylor 0:eafc3fd41f75 280 src += use_len;
bryantaylor 0:eafc3fd41f75 281 len_left -= use_len;
bryantaylor 0:eafc3fd41f75 282
bryantaylor 0:eafc3fd41f75 283 /*
bryantaylor 0:eafc3fd41f75 284 * Increment counter.
bryantaylor 0:eafc3fd41f75 285 * No need to check for overflow thanks to the length check above.
bryantaylor 0:eafc3fd41f75 286 */
bryantaylor 0:eafc3fd41f75 287 for( i = 0; i < q; i++ )
bryantaylor 0:eafc3fd41f75 288 if( ++ctr[15-i] != 0 )
bryantaylor 0:eafc3fd41f75 289 break;
bryantaylor 0:eafc3fd41f75 290 }
bryantaylor 0:eafc3fd41f75 291
bryantaylor 0:eafc3fd41f75 292 /*
bryantaylor 0:eafc3fd41f75 293 * Authentication: reset counter and crypt/mask internal tag
bryantaylor 0:eafc3fd41f75 294 */
bryantaylor 0:eafc3fd41f75 295 for( i = 0; i < q; i++ )
bryantaylor 0:eafc3fd41f75 296 ctr[15-i] = 0;
bryantaylor 0:eafc3fd41f75 297
bryantaylor 0:eafc3fd41f75 298 CTR_CRYPT( y, y, 16 );
bryantaylor 0:eafc3fd41f75 299 memcpy( tag, y, tag_len );
bryantaylor 0:eafc3fd41f75 300
bryantaylor 0:eafc3fd41f75 301 return( 0 );
bryantaylor 0:eafc3fd41f75 302 }
bryantaylor 0:eafc3fd41f75 303
bryantaylor 0:eafc3fd41f75 304 /*
bryantaylor 0:eafc3fd41f75 305 * Authenticated encryption
bryantaylor 0:eafc3fd41f75 306 */
bryantaylor 0:eafc3fd41f75 307 int mbedtls_ccm_encrypt_and_tag( mbedtls_ccm_context *ctx, size_t length,
bryantaylor 0:eafc3fd41f75 308 const unsigned char *iv, size_t iv_len,
bryantaylor 0:eafc3fd41f75 309 const unsigned char *add, size_t add_len,
bryantaylor 0:eafc3fd41f75 310 const unsigned char *input, unsigned char *output,
bryantaylor 0:eafc3fd41f75 311 unsigned char *tag, size_t tag_len )
bryantaylor 0:eafc3fd41f75 312 {
bryantaylor 0:eafc3fd41f75 313 return( ccm_auth_crypt( ctx, CCM_ENCRYPT, length, iv, iv_len,
bryantaylor 0:eafc3fd41f75 314 add, add_len, input, output, tag, tag_len ) );
bryantaylor 0:eafc3fd41f75 315 }
bryantaylor 0:eafc3fd41f75 316
bryantaylor 0:eafc3fd41f75 317 /*
bryantaylor 0:eafc3fd41f75 318 * Authenticated decryption
bryantaylor 0:eafc3fd41f75 319 */
bryantaylor 0:eafc3fd41f75 320 int mbedtls_ccm_auth_decrypt( mbedtls_ccm_context *ctx, size_t length,
bryantaylor 0:eafc3fd41f75 321 const unsigned char *iv, size_t iv_len,
bryantaylor 0:eafc3fd41f75 322 const unsigned char *add, size_t add_len,
bryantaylor 0:eafc3fd41f75 323 const unsigned char *input, unsigned char *output,
bryantaylor 0:eafc3fd41f75 324 const unsigned char *tag, size_t tag_len )
bryantaylor 0:eafc3fd41f75 325 {
bryantaylor 0:eafc3fd41f75 326 int ret;
bryantaylor 0:eafc3fd41f75 327 unsigned char check_tag[16];
bryantaylor 0:eafc3fd41f75 328 unsigned char i;
bryantaylor 0:eafc3fd41f75 329 int diff;
bryantaylor 0:eafc3fd41f75 330
bryantaylor 0:eafc3fd41f75 331 if( ( ret = ccm_auth_crypt( ctx, CCM_DECRYPT, length,
bryantaylor 0:eafc3fd41f75 332 iv, iv_len, add, add_len,
bryantaylor 0:eafc3fd41f75 333 input, output, check_tag, tag_len ) ) != 0 )
bryantaylor 0:eafc3fd41f75 334 {
bryantaylor 0:eafc3fd41f75 335 return( ret );
bryantaylor 0:eafc3fd41f75 336 }
bryantaylor 0:eafc3fd41f75 337
bryantaylor 0:eafc3fd41f75 338 /* Check tag in "constant-time" */
bryantaylor 0:eafc3fd41f75 339 for( diff = 0, i = 0; i < tag_len; i++ )
bryantaylor 0:eafc3fd41f75 340 diff |= tag[i] ^ check_tag[i];
bryantaylor 0:eafc3fd41f75 341
bryantaylor 0:eafc3fd41f75 342 if( diff != 0 )
bryantaylor 0:eafc3fd41f75 343 {
bryantaylor 0:eafc3fd41f75 344 mbedtls_zeroize( output, length );
bryantaylor 0:eafc3fd41f75 345 return( MBEDTLS_ERR_CCM_AUTH_FAILED );
bryantaylor 0:eafc3fd41f75 346 }
bryantaylor 0:eafc3fd41f75 347
bryantaylor 0:eafc3fd41f75 348 return( 0 );
bryantaylor 0:eafc3fd41f75 349 }
bryantaylor 0:eafc3fd41f75 350
bryantaylor 0:eafc3fd41f75 351
bryantaylor 0:eafc3fd41f75 352 #if defined(MBEDTLS_SELF_TEST) && defined(MBEDTLS_AES_C)
bryantaylor 0:eafc3fd41f75 353 /*
bryantaylor 0:eafc3fd41f75 354 * Examples 1 to 3 from SP800-38C Appendix C
bryantaylor 0:eafc3fd41f75 355 */
bryantaylor 0:eafc3fd41f75 356
bryantaylor 0:eafc3fd41f75 357 #define NB_TESTS 3
bryantaylor 0:eafc3fd41f75 358
bryantaylor 0:eafc3fd41f75 359 /*
bryantaylor 0:eafc3fd41f75 360 * The data is the same for all tests, only the used length changes
bryantaylor 0:eafc3fd41f75 361 */
bryantaylor 0:eafc3fd41f75 362 static const unsigned char key[] = {
bryantaylor 0:eafc3fd41f75 363 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
bryantaylor 0:eafc3fd41f75 364 0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f
bryantaylor 0:eafc3fd41f75 365 };
bryantaylor 0:eafc3fd41f75 366
bryantaylor 0:eafc3fd41f75 367 static const unsigned char iv[] = {
bryantaylor 0:eafc3fd41f75 368 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
bryantaylor 0:eafc3fd41f75 369 0x18, 0x19, 0x1a, 0x1b
bryantaylor 0:eafc3fd41f75 370 };
bryantaylor 0:eafc3fd41f75 371
bryantaylor 0:eafc3fd41f75 372 static const unsigned char ad[] = {
bryantaylor 0:eafc3fd41f75 373 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
bryantaylor 0:eafc3fd41f75 374 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
bryantaylor 0:eafc3fd41f75 375 0x10, 0x11, 0x12, 0x13
bryantaylor 0:eafc3fd41f75 376 };
bryantaylor 0:eafc3fd41f75 377
bryantaylor 0:eafc3fd41f75 378 static const unsigned char msg[] = {
bryantaylor 0:eafc3fd41f75 379 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
bryantaylor 0:eafc3fd41f75 380 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
bryantaylor 0:eafc3fd41f75 381 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
bryantaylor 0:eafc3fd41f75 382 };
bryantaylor 0:eafc3fd41f75 383
bryantaylor 0:eafc3fd41f75 384 static const size_t iv_len [NB_TESTS] = { 7, 8, 12 };
bryantaylor 0:eafc3fd41f75 385 static const size_t add_len[NB_TESTS] = { 8, 16, 20 };
bryantaylor 0:eafc3fd41f75 386 static const size_t msg_len[NB_TESTS] = { 4, 16, 24 };
bryantaylor 0:eafc3fd41f75 387 static const size_t tag_len[NB_TESTS] = { 4, 6, 8 };
bryantaylor 0:eafc3fd41f75 388
bryantaylor 0:eafc3fd41f75 389 static const unsigned char res[NB_TESTS][32] = {
bryantaylor 0:eafc3fd41f75 390 { 0x71, 0x62, 0x01, 0x5b, 0x4d, 0xac, 0x25, 0x5d },
bryantaylor 0:eafc3fd41f75 391 { 0xd2, 0xa1, 0xf0, 0xe0, 0x51, 0xea, 0x5f, 0x62,
bryantaylor 0:eafc3fd41f75 392 0x08, 0x1a, 0x77, 0x92, 0x07, 0x3d, 0x59, 0x3d,
bryantaylor 0:eafc3fd41f75 393 0x1f, 0xc6, 0x4f, 0xbf, 0xac, 0xcd },
bryantaylor 0:eafc3fd41f75 394 { 0xe3, 0xb2, 0x01, 0xa9, 0xf5, 0xb7, 0x1a, 0x7a,
bryantaylor 0:eafc3fd41f75 395 0x9b, 0x1c, 0xea, 0xec, 0xcd, 0x97, 0xe7, 0x0b,
bryantaylor 0:eafc3fd41f75 396 0x61, 0x76, 0xaa, 0xd9, 0xa4, 0x42, 0x8a, 0xa5,
bryantaylor 0:eafc3fd41f75 397 0x48, 0x43, 0x92, 0xfb, 0xc1, 0xb0, 0x99, 0x51 }
bryantaylor 0:eafc3fd41f75 398 };
bryantaylor 0:eafc3fd41f75 399
bryantaylor 0:eafc3fd41f75 400 int mbedtls_ccm_self_test( int verbose )
bryantaylor 0:eafc3fd41f75 401 {
bryantaylor 0:eafc3fd41f75 402 mbedtls_ccm_context ctx;
bryantaylor 0:eafc3fd41f75 403 unsigned char out[32];
bryantaylor 0:eafc3fd41f75 404 size_t i;
bryantaylor 0:eafc3fd41f75 405 int ret;
bryantaylor 0:eafc3fd41f75 406
bryantaylor 0:eafc3fd41f75 407 mbedtls_ccm_init( &ctx );
bryantaylor 0:eafc3fd41f75 408
bryantaylor 0:eafc3fd41f75 409 if( mbedtls_ccm_setkey( &ctx, MBEDTLS_CIPHER_ID_AES, key, 8 * sizeof key ) != 0 )
bryantaylor 0:eafc3fd41f75 410 {
bryantaylor 0:eafc3fd41f75 411 if( verbose != 0 )
bryantaylor 0:eafc3fd41f75 412 mbedtls_printf( " CCM: setup failed" );
bryantaylor 0:eafc3fd41f75 413
bryantaylor 0:eafc3fd41f75 414 return( 1 );
bryantaylor 0:eafc3fd41f75 415 }
bryantaylor 0:eafc3fd41f75 416
bryantaylor 0:eafc3fd41f75 417 for( i = 0; i < NB_TESTS; i++ )
bryantaylor 0:eafc3fd41f75 418 {
bryantaylor 0:eafc3fd41f75 419 if( verbose != 0 )
bryantaylor 0:eafc3fd41f75 420 mbedtls_printf( " CCM-AES #%u: ", (unsigned int) i + 1 );
bryantaylor 0:eafc3fd41f75 421
bryantaylor 0:eafc3fd41f75 422 ret = mbedtls_ccm_encrypt_and_tag( &ctx, msg_len[i],
bryantaylor 0:eafc3fd41f75 423 iv, iv_len[i], ad, add_len[i],
bryantaylor 0:eafc3fd41f75 424 msg, out,
bryantaylor 0:eafc3fd41f75 425 out + msg_len[i], tag_len[i] );
bryantaylor 0:eafc3fd41f75 426
bryantaylor 0:eafc3fd41f75 427 if( ret != 0 ||
bryantaylor 0:eafc3fd41f75 428 memcmp( out, res[i], msg_len[i] + tag_len[i] ) != 0 )
bryantaylor 0:eafc3fd41f75 429 {
bryantaylor 0:eafc3fd41f75 430 if( verbose != 0 )
bryantaylor 0:eafc3fd41f75 431 mbedtls_printf( "failed\n" );
bryantaylor 0:eafc3fd41f75 432
bryantaylor 0:eafc3fd41f75 433 return( 1 );
bryantaylor 0:eafc3fd41f75 434 }
bryantaylor 0:eafc3fd41f75 435
bryantaylor 0:eafc3fd41f75 436 ret = mbedtls_ccm_auth_decrypt( &ctx, msg_len[i],
bryantaylor 0:eafc3fd41f75 437 iv, iv_len[i], ad, add_len[i],
bryantaylor 0:eafc3fd41f75 438 res[i], out,
bryantaylor 0:eafc3fd41f75 439 res[i] + msg_len[i], tag_len[i] );
bryantaylor 0:eafc3fd41f75 440
bryantaylor 0:eafc3fd41f75 441 if( ret != 0 ||
bryantaylor 0:eafc3fd41f75 442 memcmp( out, msg, msg_len[i] ) != 0 )
bryantaylor 0:eafc3fd41f75 443 {
bryantaylor 0:eafc3fd41f75 444 if( verbose != 0 )
bryantaylor 0:eafc3fd41f75 445 mbedtls_printf( "failed\n" );
bryantaylor 0:eafc3fd41f75 446
bryantaylor 0:eafc3fd41f75 447 return( 1 );
bryantaylor 0:eafc3fd41f75 448 }
bryantaylor 0:eafc3fd41f75 449
bryantaylor 0:eafc3fd41f75 450 if( verbose != 0 )
bryantaylor 0:eafc3fd41f75 451 mbedtls_printf( "passed\n" );
bryantaylor 0:eafc3fd41f75 452 }
bryantaylor 0:eafc3fd41f75 453
bryantaylor 0:eafc3fd41f75 454 mbedtls_ccm_free( &ctx );
bryantaylor 0:eafc3fd41f75 455
bryantaylor 0:eafc3fd41f75 456 if( verbose != 0 )
bryantaylor 0:eafc3fd41f75 457 mbedtls_printf( "\n" );
bryantaylor 0:eafc3fd41f75 458
bryantaylor 0:eafc3fd41f75 459 return( 0 );
bryantaylor 0:eafc3fd41f75 460 }
bryantaylor 0:eafc3fd41f75 461
bryantaylor 0:eafc3fd41f75 462 #endif /* MBEDTLS_SELF_TEST && MBEDTLS_AES_C */
bryantaylor 0:eafc3fd41f75 463
bryantaylor 0:eafc3fd41f75 464 #endif /* MBEDTLS_CCM_C */