reactos/dll/3rdparty/mbedtls/ccm.c

   1 /*
   2  *  NIST SP800-38C compliant CCM implementation
   3  *
   4  *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
   5  *  SPDX-License-Identifier: GPL-2.0
   6  *
   7  *  This program is free software; you can redistribute it and/or modify
   8  *  it under the terms of the GNU General Public License as published by
   9  *  the Free Software Foundation; either version 2 of the License, or
  10  *  (at your option) any later version.
  11  *
  12  *  This program is distributed in the hope that it will be useful,
  13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *  GNU General Public License for more details.
  16  *
  17  *  You should have received a copy of the GNU General Public License along
  18  *  with this program; if not, write to the Free Software Foundation, Inc.,
  19  *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  *  This file is part of mbed TLS (https://tls.mbed.org)
  22  */
  23
  24 /*
  25  * Definition of CCM:
  26  * http://csrc.nist.gov/publications/nistpubs/800-38C/SP800-38C_updated-July20_2007.pdf
  27  * RFC 3610 "Counter with CBC-MAC (CCM)"
  28  *
  29  * Related:
  30  * RFC 5116 "An Interface and Algorithms for Authenticated Encryption"
  31  */
  32
  33 #if !defined(MBEDTLS_CONFIG_FILE)
  34 #include "mbedtls/config.h"
  35 #else
  36 #include MBEDTLS_CONFIG_FILE
  37 #endif
  38
  39 #if defined(MBEDTLS_CCM_C)
  40
  41 #include "mbedtls/ccm.h"
  42
  43 #include <string.h>
  44
  45 #if defined(MBEDTLS_SELF_TEST) && defined(MBEDTLS_AES_C)
  46 #if defined(MBEDTLS_PLATFORM_C)
  47 #include "mbedtls/platform.h"
  48 #else
  49 #include <stdio.h>
  50 #define mbedtls_printf printf
  51 #endif /* MBEDTLS_PLATFORM_C */
  52 #endif /* MBEDTLS_SELF_TEST && MBEDTLS_AES_C */
  53
  54 /* Implementation that should never be optimized out by the compiler */
  55 static void mbedtls_zeroize( void *v, size_t n ) {
  56     volatile unsigned char *p = (unsigned char*)v; while( n-- ) *p++ = 0;
  57 }
  58
  59 #define CCM_ENCRYPT 0
  60 #define CCM_DECRYPT 1
  61
  62 /*
  63  * Initialize context
  64  */
  65 void mbedtls_ccm_init( mbedtls_ccm_context *ctx )
  66 {
  67     memset( ctx, 0, sizeof( mbedtls_ccm_context ) );
  68 }
  69
  70 int mbedtls_ccm_setkey( mbedtls_ccm_context *ctx,
  71                         mbedtls_cipher_id_t cipher,
  72                         const unsigned char *key,
  73                         unsigned int keybits )
  74 {
  75     int ret;
  76     const mbedtls_cipher_info_t *cipher_info;
  77
  78     cipher_info = mbedtls_cipher_info_from_values( cipher, keybits, MBEDTLS_MODE_ECB );
  79     if( cipher_info == NULL )
  80         return( MBEDTLS_ERR_CCM_BAD_INPUT );
  81
  82     if( cipher_info->block_size != 16 )
  83         return( MBEDTLS_ERR_CCM_BAD_INPUT );
  84
  85     mbedtls_cipher_free( &ctx->cipher_ctx );
  86
  87     if( ( ret = mbedtls_cipher_setup( &ctx->cipher_ctx, cipher_info ) ) != 0 )
  88         return( ret );
  89
  90     if( ( ret = mbedtls_cipher_setkey( &ctx->cipher_ctx, key, keybits,
  91                                MBEDTLS_ENCRYPT ) ) != 0 )
  92     {
  93         return( ret );
  94     }
  95
  96     return( 0 );
  97 }
  98
  99 /*
 100  * Free context
 101  */
 102 void mbedtls_ccm_free( mbedtls_ccm_context *ctx )
 103 {
 104     mbedtls_cipher_free( &ctx->cipher_ctx );
 105     mbedtls_zeroize( ctx, sizeof( mbedtls_ccm_context ) );
 106 }
 107
 108 /*
 109  * Macros for common operations.
 110  * Results in smaller compiled code than static inline functions.
 111  */
 112
 113 /*
 114  * Update the CBC-MAC state in y using a block in b
 115  * (Always using b as the source helps the compiler optimise a bit better.)
 116  */
 117 #define UPDATE_CBC_MAC                                                      \
 118     for( i = 0; i < 16; i++ )                                               \
 119         y[i] ^= b[i];                                                       \
 120                                                                             \
 121     if( ( ret = mbedtls_cipher_update( &ctx->cipher_ctx, y, 16, y, &olen ) ) != 0 ) \
 122         return( ret );
 123
 124 /*
 125  * Encrypt or decrypt a partial block with CTR
 126  * Warning: using b for temporary storage! src and dst must not be b!
 127  * This avoids allocating one more 16 bytes buffer while allowing src == dst.
 128  */
 129 #define CTR_CRYPT( dst, src, len  )                                            \
 130     if( ( ret = mbedtls_cipher_update( &ctx->cipher_ctx, ctr, 16, b, &olen ) ) != 0 )  \
 131         return( ret );                                                         \
 132                                                                                \
 133     for( i = 0; i < len; i++ )                                                 \
 134         dst[i] = src[i] ^ b[i];
 135
 136 /*
 137  * Authenticated encryption or decryption
 138  */
 139 static int ccm_auth_crypt( mbedtls_ccm_context *ctx, int mode, size_t length,
 140                            const unsigned char *iv, size_t iv_len,
 141                            const unsigned char *add, size_t add_len,
 142                            const unsigned char *input, unsigned char *output,
 143                            unsigned char *tag, size_t tag_len )
 144 {
 145     int ret;
 146     unsigned char i;
 147     unsigned char q;
 148     size_t len_left, olen;
 149     unsigned char b[16];
 150     unsigned char y[16];
 151     unsigned char ctr[16];
 152     const unsigned char *src;
 153     unsigned char *dst;
 154
 155     /*
 156      * Check length requirements: SP800-38C A.1
 157      * Additional requirement: a < 2^16 - 2^8 to simplify the code.
 158      * 'length' checked later (when writing it to the first block)
 159      */
 160     if( tag_len < 4 || tag_len > 16 || tag_len % 2 != 0 )
 161         return( MBEDTLS_ERR_CCM_BAD_INPUT );
 162
 163     /* Also implies q is within bounds */
 164     if( iv_len < 7 || iv_len > 13 )
 165         return( MBEDTLS_ERR_CCM_BAD_INPUT );
 166
 167     if( add_len > 0xFF00 )
 168         return( MBEDTLS_ERR_CCM_BAD_INPUT );
 169
 170     q = 16 - 1 - (unsigned char) iv_len;
 171
 172     /*
 173      * First block B_0:
 174      * 0        .. 0        flags
 175      * 1        .. iv_len   nonce (aka iv)
 176      * iv_len+1 .. 15       length
 177      *
 178      * With flags as (bits):
 179      * 7        0
 180      * 6        add present?
 181      * 5 .. 3   (t - 2) / 2
 182      * 2 .. 0   q - 1
 183      */
 184     b[0] = 0;
 185     b[0] |= ( add_len > 0 ) << 6;
 186     b[0] |= ( ( tag_len - 2 ) / 2 ) << 3;
 187     b[0] |= q - 1;
 188
 189     memcpy( b + 1, iv, iv_len );
 190
 191     for( i = 0, len_left = length; i < q; i++, len_left >>= 8 )
 192         b[15-i] = (unsigned char)( len_left & 0xFF );
 193
 194     if( len_left > 0 )
 195         return( MBEDTLS_ERR_CCM_BAD_INPUT );
 196
 197
 198     /* Start CBC-MAC with first block */
 199     memset( y, 0, 16 );
 200     UPDATE_CBC_MAC;
 201
 202     /*
 203      * If there is additional data, update CBC-MAC with
 204      * add_len, add, 0 (padding to a block boundary)
 205      */
 206     if( add_len > 0 )
 207     {
 208         size_t use_len;
 209         len_left = add_len;
 210         src = add;
 211
 212         memset( b, 0, 16 );
 213         b[0] = (unsigned char)( ( add_len >> 8 ) & 0xFF );
 214         b[1] = (unsigned char)( ( add_len      ) & 0xFF );
 215
 216         use_len = len_left < 16 - 2 ? len_left : 16 - 2;
 217         memcpy( b + 2, src, use_len );
 218         len_left -= use_len;
 219         src += use_len;
 220
 221         UPDATE_CBC_MAC;
 222
 223         while( len_left > 0 )
 224         {
 225             use_len = len_left > 16 ? 16 : len_left;
 226
 227             memset( b, 0, 16 );
 228             memcpy( b, src, use_len );
 229             UPDATE_CBC_MAC;
 230
 231             len_left -= use_len;
 232             src += use_len;
 233         }
 234     }
 235
 236     /*
 237      * Prepare counter block for encryption:
 238      * 0        .. 0        flags
 239      * 1        .. iv_len   nonce (aka iv)
 240      * iv_len+1 .. 15       counter (initially 1)
 241      *
 242      * With flags as (bits):
 243      * 7 .. 3   0
 244      * 2 .. 0   q - 1
 245      */
 246     ctr[0] = q - 1;
 247     memcpy( ctr + 1, iv, iv_len );
 248     memset( ctr + 1 + iv_len, 0, q );
 249     ctr[15] = 1;
 250
 251     /*
 252      * Authenticate and {en,de}crypt the message.
 253      *
 254      * The only difference between encryption and decryption is
 255      * the respective order of authentication and {en,de}cryption.
 256      */
 257     len_left = length;
 258     src = input;
 259     dst = output;
 260
 261     while( len_left > 0 )
 262     {
 263         size_t use_len = len_left > 16 ? 16 : len_left;
 264
 265         if( mode == CCM_ENCRYPT )
 266         {
 267             memset( b, 0, 16 );
 268             memcpy( b, src, use_len );
 269             UPDATE_CBC_MAC;
 270         }
 271
 272         CTR_CRYPT( dst, src, use_len );
 273
 274         if( mode == CCM_DECRYPT )
 275         {
 276             memset( b, 0, 16 );
 277             memcpy( b, dst, use_len );
 278             UPDATE_CBC_MAC;
 279         }
 280
 281         dst += use_len;
 282         src += use_len;
 283         len_left -= use_len;
 284
 285         /*
 286          * Increment counter.
 287          * No need to check for overflow thanks to the length check above.
 288          */
 289         for( i = 0; i < q; i++ )
 290             if( ++ctr[15-i] != 0 )
 291                 break;
 292     }
 293
 294     /*
 295      * Authentication: reset counter and crypt/mask internal tag
 296      */
 297     for( i = 0; i < q; i++ )
 298         ctr[15-i] = 0;
 299
 300     CTR_CRYPT( y, y, 16 );
 301     memcpy( tag, y, tag_len );
 302
 303     return( 0 );
 304 }
 305
 306 /*
 307  * Authenticated encryption
 308  */
 309 int mbedtls_ccm_encrypt_and_tag( mbedtls_ccm_context *ctx, size_t length,
 310                          const unsigned char *iv, size_t iv_len,
 311                          const unsigned char *add, size_t add_len,
 312                          const unsigned char *input, unsigned char *output,
 313                          unsigned char *tag, size_t tag_len )
 314 {
 315     return( ccm_auth_crypt( ctx, CCM_ENCRYPT, length, iv, iv_len,
 316                             add, add_len, input, output, tag, tag_len ) );
 317 }
 318
 319 /*
 320  * Authenticated decryption
 321  */
 322 int mbedtls_ccm_auth_decrypt( mbedtls_ccm_context *ctx, size_t length,
 323                       const unsigned char *iv, size_t iv_len,
 324                       const unsigned char *add, size_t add_len,
 325                       const unsigned char *input, unsigned char *output,
 326                       const unsigned char *tag, size_t tag_len )
 327 {
 328     int ret;
 329     unsigned char check_tag[16];
 330     unsigned char i;
 331     int diff;
 332
 333     if( ( ret = ccm_auth_crypt( ctx, CCM_DECRYPT, length,
 334                                 iv, iv_len, add, add_len,
 335                                 input, output, check_tag, tag_len ) ) != 0 )
 336     {
 337         return( ret );
 338     }
 339
 340     /* Check tag in "constant-time" */
 341     for( diff = 0, i = 0; i < tag_len; i++ )
 342         diff |= tag[i] ^ check_tag[i];
 343
 344     if( diff != 0 )
 345     {
 346         mbedtls_zeroize( output, length );
 347         return( MBEDTLS_ERR_CCM_AUTH_FAILED );
 348     }
 349
 350     return( 0 );
 351 }
 352
 353
 354 #if defined(MBEDTLS_SELF_TEST) && defined(MBEDTLS_AES_C)
 355 /*
 356  * Examples 1 to 3 from SP800-38C Appendix C
 357  */
 358
 359 #define NB_TESTS 3
 360
 361 /*
 362  * The data is the same for all tests, only the used length changes
 363  */
 364 static const unsigned char key[] = {
 365     0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
 366     0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f
 367 };
 368
 369 static const unsigned char iv[] = {
 370     0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
 371     0x18, 0x19, 0x1a, 0x1b
 372 };
 373
 374 static const unsigned char ad[] = {
 375     0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
 376     0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
 377     0x10, 0x11, 0x12, 0x13
 378 };
 379
 380 static const unsigned char msg[] = {
 381     0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
 382     0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
 383     0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
 384 };
 385
 386 static const size_t iv_len [NB_TESTS] = { 7, 8,  12 };
 387 static const size_t add_len[NB_TESTS] = { 8, 16, 20 };
 388 static const size_t msg_len[NB_TESTS] = { 4, 16, 24 };
 389 static const size_t tag_len[NB_TESTS] = { 4, 6,  8  };
 390
 391 static const unsigned char res[NB_TESTS][32] = {
 392     {   0x71, 0x62, 0x01, 0x5b, 0x4d, 0xac, 0x25, 0x5d },
 393     {   0xd2, 0xa1, 0xf0, 0xe0, 0x51, 0xea, 0x5f, 0x62,
 394         0x08, 0x1a, 0x77, 0x92, 0x07, 0x3d, 0x59, 0x3d,
 395         0x1f, 0xc6, 0x4f, 0xbf, 0xac, 0xcd },
 396     {   0xe3, 0xb2, 0x01, 0xa9, 0xf5, 0xb7, 0x1a, 0x7a,
 397         0x9b, 0x1c, 0xea, 0xec, 0xcd, 0x97, 0xe7, 0x0b,
 398         0x61, 0x76, 0xaa, 0xd9, 0xa4, 0x42, 0x8a, 0xa5,
 399         0x48, 0x43, 0x92, 0xfb, 0xc1, 0xb0, 0x99, 0x51 }
 400 };
 401
 402 int mbedtls_ccm_self_test( int verbose )
 403 {
 404     mbedtls_ccm_context ctx;
 405     unsigned char out[32];
 406     size_t i;
 407     int ret;
 408
 409     mbedtls_ccm_init( &ctx );
 410
 411     if( mbedtls_ccm_setkey( &ctx, MBEDTLS_CIPHER_ID_AES, key, 8 * sizeof key ) != 0 )
 412     {
 413         if( verbose != 0 )
 414             mbedtls_printf( "  CCM: setup failed" );
 415
 416         return( 1 );
 417     }
 418
 419     for( i = 0; i < NB_TESTS; i++ )
 420     {
 421         if( verbose != 0 )
 422             mbedtls_printf( "  CCM-AES #%u: ", (unsigned int) i + 1 );
 423
 424         ret = mbedtls_ccm_encrypt_and_tag( &ctx, msg_len[i],
 425                                    iv, iv_len[i], ad, add_len[i],
 426                                    msg, out,
 427                                    out + msg_len[i], tag_len[i] );
 428
 429         if( ret != 0 ||
 430             memcmp( out, res[i], msg_len[i] + tag_len[i] ) != 0 )
 431         {
 432             if( verbose != 0 )
 433                 mbedtls_printf( "failed\n" );
 434
 435             return( 1 );
 436         }
 437
 438         ret = mbedtls_ccm_auth_decrypt( &ctx, msg_len[i],
 439                                 iv, iv_len[i], ad, add_len[i],
 440                                 res[i], out,
 441                                 res[i] + msg_len[i], tag_len[i] );
 442
 443         if( ret != 0 ||
 444             memcmp( out, msg, msg_len[i] ) != 0 )
 445         {
 446             if( verbose != 0 )
 447                 mbedtls_printf( "failed\n" );
 448
 449             return( 1 );
 450         }
 451
 452         if( verbose != 0 )
 453             mbedtls_printf( "passed\n" );
 454     }
 455
 456     mbedtls_ccm_free( &ctx );
 457
 458     if( verbose != 0 )
 459         mbedtls_printf( "\n" );
 460
 461     return( 0 );
 462 }
 463
 464 #endif /* MBEDTLS_SELF_TEST && MBEDTLS_AES_C */
 465
 466 #endif /* MBEDTLS_CCM_C */