1 /* 2 * Copyright (C) 2017 BlueKitchen GmbH 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the copyright holders nor the names of 14 * contributors may be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY MATTHIAS RINGWALD AND CONTRIBUTORS 18 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 19 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 20 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS 21 * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 23 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 24 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 25 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 26 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF 27 * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 * 30 */ 31 32 #define __BTSTACK_FILE__ "btstack_crypto.c" 33 34 /* 35 * btstack_crypto.h 36 * 37 * Central place for all crypto-related functions with completion callbacks to allow 38 * using of MCU crypto peripherals or the Bluetooth controller 39 */ 40 41 #include "btstack_crypto.h" 42 43 #include "btstack_debug.h" 44 #include "btstack_event.h" 45 #include "btstack_linked_list.h" 46 #include "btstack_util.h" 47 #include "hci.h" 48 49 // backwards-compatitility ENABLE_MICRO_ECC_FOR_LE_SECURE_CONNECTIONS -> ENABLE_MICRO_ECC_P256 50 #if defined(ENABLE_MICRO_ECC_FOR_LE_SECURE_CONNECTIONS) && !defined(ENABLE_MICRO_ECC_P256) 51 #define ENABLE_MICRO_ECC_P256 52 #endif 53 54 // configure ECC implementations 55 #if defined(ENABLE_MICRO_ECC_P256) && defined(HAVE_MBEDTLS_ECC_P256) 56 #error "If you have mbedTLS (HAVE_MBEDTLS_ECC_P256), please disable uECC (ENABLE_MICRO_ECC_P256) in bstack_config.h" 57 #endif 58 59 // Software ECC-P256 implementation provided by micro-ecc 60 #ifdef ENABLE_MICRO_ECC_P256 61 #define ENABLE_ECC_P256 62 #define USE_MICRO_ECC_P256 63 #define USE_SOFTWARE_ECC_P256_IMPLEMENTATION 64 #include "uECC.h" 65 #endif 66 67 // Software ECC-P256 implementation provided by mbedTLS 68 #ifdef HAVE_MBEDTLS_ECC_P256 69 #define ENABLE_ECC_P256 70 #define USE_MBEDTLS_ECC_P256 71 #define USE_SOFTWARE_ECC_P256_IMPLEMENTATION 72 #include "mbedtls/config.h" 73 #include "mbedtls/platform.h" 74 #include "mbedtls/ecp.h" 75 #endif 76 77 #if defined(ENABLE_LE_SECURE_CONNECTIONS) && !defined(ENABLE_ECC_P256) 78 #define ENABLE_ECC_P256 79 #endif 80 81 // Software AES128 82 #ifdef HAVE_AES128 83 #define USE_BTSTACK_AES128 84 void btstack_aes128_calc(const uint8_t * key, const uint8_t * plaintext, uint8_t * result); 85 #endif 86 87 typedef enum { 88 CMAC_IDLE, 89 CMAC_CALC_SUBKEYS, 90 CMAC_W4_SUBKEYS, 91 CMAC_CALC_MI, 92 CMAC_W4_MI, 93 CMAC_CALC_MLAST, 94 CMAC_W4_MLAST 95 } btstack_crypto_cmac_state_t; 96 97 typedef enum { 98 ECC_P256_KEY_GENERATION_IDLE, 99 ECC_P256_KEY_GENERATION_GENERATING_RANDOM, 100 ECC_P256_KEY_GENERATION_ACTIVE, 101 ECC_P256_KEY_GENERATION_W4_KEY, 102 ECC_P256_KEY_GENERATION_DONE, 103 } btstack_crypto_ecc_p256_key_generation_state_t; 104 105 static void btstack_crypto_run(void); 106 107 const static uint8_t zero[16] = { 0 }; 108 109 static uint8_t btstack_crypto_initialized; 110 static btstack_linked_list_t btstack_crypto_operations; 111 static btstack_packet_callback_registration_t hci_event_callback_registration; 112 static uint8_t btstack_crypto_wait_for_hci_result; 113 114 // state for AES-CMAC 115 static btstack_crypto_cmac_state_t btstack_crypto_cmac_state; 116 static sm_key_t btstack_crypto_cmac_k; 117 static sm_key_t btstack_crypto_cmac_x; 118 static sm_key_t btstack_crypto_cmac_m_last; 119 static uint8_t btstack_crypto_cmac_block_current; 120 static uint8_t btstack_crypto_cmac_block_count; 121 122 // state for AES-CCM 123 #ifndef USE_BTSTACK_AES128 124 static uint8_t btstack_crypto_ccm_s[16]; 125 #endif 126 127 #ifdef ENABLE_ECC_P256 128 129 static uint8_t btstack_crypto_ecc_p256_public_key[64]; 130 static uint8_t btstack_crypto_ecc_p256_random[64]; 131 static uint8_t btstack_crypto_ecc_p256_random_len; 132 static uint8_t btstack_crypto_ecc_p256_random_offset; 133 static btstack_crypto_ecc_p256_key_generation_state_t btstack_crypto_ecc_p256_key_generation_state; 134 135 #ifdef USE_SOFTWARE_ECC_P256_IMPLEMENTATION 136 static uint8_t btstack_crypto_ecc_p256_d[32]; 137 #endif 138 139 // Software ECDH implementation provided by mbedtls 140 #ifdef USE_MBEDTLS_ECC_P256 141 static mbedtls_ecp_group mbedtls_ec_group; 142 #endif 143 144 #endif /* ENABLE_ECC_P256 */ 145 146 static void btstack_crypto_done(btstack_crypto_t * btstack_crypto){ 147 btstack_linked_list_pop(&btstack_crypto_operations); 148 (*btstack_crypto->context_callback.callback)(btstack_crypto->context_callback.context); 149 } 150 151 static inline void btstack_crypto_cmac_next_state(void){ 152 btstack_crypto_cmac_state = (btstack_crypto_cmac_state_t) (((int)btstack_crypto_cmac_state) + 1); 153 } 154 155 static int btstack_crypto_cmac_last_block_complete(btstack_crypto_aes128_cmac_t * btstack_crypto_cmac){ 156 uint16_t len = btstack_crypto_cmac->size; 157 if (len == 0) return 0; 158 return (len & 0x0f) == 0; 159 } 160 161 static void btstack_crypto_aes128_start(const sm_key_t key, const sm_key_t plaintext){ 162 uint8_t key_flipped[16]; 163 uint8_t plaintext_flipped[16]; 164 reverse_128(key, key_flipped); 165 reverse_128(plaintext, plaintext_flipped); 166 btstack_crypto_wait_for_hci_result = 1; 167 hci_send_cmd(&hci_le_encrypt, key_flipped, plaintext_flipped); 168 } 169 170 static uint8_t btstack_crypto_cmac_get_byte(btstack_crypto_aes128_cmac_t * btstack_crypto_cmac, uint16_t pos){ 171 if (btstack_crypto_cmac->btstack_crypto.operation == BTSTACK_CRYPTO_CMAC_GENERATOR){ 172 return (*btstack_crypto_cmac->data.get_byte_callback)(pos); 173 } else { 174 return btstack_crypto_cmac->data.message[pos]; 175 } 176 } 177 178 static void btstack_crypto_cmac_handle_aes_engine_ready(btstack_crypto_aes128_cmac_t * btstack_crypto_cmac){ 179 switch (btstack_crypto_cmac_state){ 180 case CMAC_CALC_SUBKEYS: { 181 sm_key_t const_zero; 182 memset(const_zero, 0, 16); 183 btstack_crypto_cmac_next_state(); 184 btstack_crypto_aes128_start(btstack_crypto_cmac_k, const_zero); 185 break; 186 } 187 case CMAC_CALC_MI: { 188 int j; 189 sm_key_t y; 190 for (j=0;j<16;j++){ 191 y[j] = btstack_crypto_cmac_x[j] ^ btstack_crypto_cmac_get_byte(btstack_crypto_cmac, btstack_crypto_cmac_block_current*16 + j); 192 } 193 btstack_crypto_cmac_block_current++; 194 btstack_crypto_cmac_next_state(); 195 btstack_crypto_aes128_start(btstack_crypto_cmac_k, y); 196 break; 197 } 198 case CMAC_CALC_MLAST: { 199 int i; 200 sm_key_t y; 201 for (i=0;i<16;i++){ 202 y[i] = btstack_crypto_cmac_x[i] ^ btstack_crypto_cmac_m_last[i]; 203 } 204 btstack_crypto_cmac_block_current++; 205 btstack_crypto_cmac_next_state(); 206 btstack_crypto_aes128_start(btstack_crypto_cmac_k, y); 207 break; 208 } 209 default: 210 log_info("btstack_crypto_cmac_handle_aes_engine_ready called in state %u", btstack_crypto_cmac_state); 211 break; 212 } 213 } 214 215 static void btstack_crypto_cmac_shift_left_by_one_bit_inplace(int len, uint8_t * data){ 216 int i; 217 int carry = 0; 218 for (i=len-1; i >= 0 ; i--){ 219 int new_carry = data[i] >> 7; 220 data[i] = data[i] << 1 | carry; 221 carry = new_carry; 222 } 223 } 224 225 static void btstack_crypto_cmac_handle_encryption_result(btstack_crypto_aes128_cmac_t * btstack_crypto_cmac, sm_key_t data){ 226 switch (btstack_crypto_cmac_state){ 227 case CMAC_W4_SUBKEYS: { 228 sm_key_t k1; 229 memcpy(k1, data, 16); 230 btstack_crypto_cmac_shift_left_by_one_bit_inplace(16, k1); 231 if (data[0] & 0x80){ 232 k1[15] ^= 0x87; 233 } 234 sm_key_t k2; 235 memcpy(k2, k1, 16); 236 btstack_crypto_cmac_shift_left_by_one_bit_inplace(16, k2); 237 if (k1[0] & 0x80){ 238 k2[15] ^= 0x87; 239 } 240 241 log_info_key("k", btstack_crypto_cmac_k); 242 log_info_key("k1", k1); 243 log_info_key("k2", k2); 244 245 // step 4: set m_last 246 int i; 247 if (btstack_crypto_cmac_last_block_complete(btstack_crypto_cmac)){ 248 for (i=0;i<16;i++){ 249 btstack_crypto_cmac_m_last[i] = btstack_crypto_cmac_get_byte(btstack_crypto_cmac, btstack_crypto_cmac->size - 16 + i) ^ k1[i]; 250 } 251 } else { 252 int valid_octets_in_last_block = btstack_crypto_cmac->size & 0x0f; 253 for (i=0;i<16;i++){ 254 if (i < valid_octets_in_last_block){ 255 btstack_crypto_cmac_m_last[i] = btstack_crypto_cmac_get_byte(btstack_crypto_cmac, (btstack_crypto_cmac->size & 0xfff0) + i) ^ k2[i]; 256 continue; 257 } 258 if (i == valid_octets_in_last_block){ 259 btstack_crypto_cmac_m_last[i] = 0x80 ^ k2[i]; 260 continue; 261 } 262 btstack_crypto_cmac_m_last[i] = k2[i]; 263 } 264 } 265 266 // next 267 btstack_crypto_cmac_state = btstack_crypto_cmac_block_current < btstack_crypto_cmac_block_count - 1 ? CMAC_CALC_MI : CMAC_CALC_MLAST; 268 break; 269 } 270 case CMAC_W4_MI: 271 memcpy(btstack_crypto_cmac_x, data, 16); 272 btstack_crypto_cmac_state = btstack_crypto_cmac_block_current < btstack_crypto_cmac_block_count - 1 ? CMAC_CALC_MI : CMAC_CALC_MLAST; 273 break; 274 case CMAC_W4_MLAST: 275 // done 276 log_info("Setting CMAC Engine to IDLE"); 277 btstack_crypto_cmac_state = CMAC_IDLE; 278 log_info_key("CMAC", data); 279 memcpy(btstack_crypto_cmac->hash, data, 16); 280 btstack_linked_list_pop(&btstack_crypto_operations); 281 (*btstack_crypto_cmac->btstack_crypto.context_callback.callback)(btstack_crypto_cmac->btstack_crypto.context_callback.context); 282 break; 283 default: 284 log_info("btstack_crypto_cmac_handle_encryption_result called in state %u", btstack_crypto_cmac_state); 285 break; 286 } 287 } 288 289 static void btstack_crypto_cmac_start(btstack_crypto_aes128_cmac_t * btstack_crypto_cmac){ 290 291 memcpy(btstack_crypto_cmac_k, btstack_crypto_cmac->key, 16); 292 memset(btstack_crypto_cmac_x, 0, 16); 293 btstack_crypto_cmac_block_current = 0; 294 295 // step 2: n := ceil(len/const_Bsize); 296 btstack_crypto_cmac_block_count = (btstack_crypto_cmac->size + 15) / 16; 297 298 // step 3: .. 299 if (btstack_crypto_cmac_block_count==0){ 300 btstack_crypto_cmac_block_count = 1; 301 } 302 log_info("btstack_crypto_cmac_start: len %u, block count %u", btstack_crypto_cmac->size, btstack_crypto_cmac_block_count); 303 304 // first, we need to compute l for k1, k2, and m_last 305 btstack_crypto_cmac_state = CMAC_CALC_SUBKEYS; 306 307 // let's go 308 btstack_crypto_cmac_handle_aes_engine_ready(btstack_crypto_cmac); 309 } 310 311 #ifndef USE_BTSTACK_AES128 312 313 /* 314 To encrypt the message data we use Counter (CTR) mode. We first 315 define the key stream blocks by: 316 317 S_i := E( K, A_i ) for i=0, 1, 2, ... 318 319 The values A_i are formatted as follows, where the Counter field i is 320 encoded in most-significant-byte first order: 321 322 Octet Number Contents 323 ------------ --------- 324 0 Flags 325 1 ... 15-L Nonce N 326 16-L ... 15 Counter i 327 328 Bit Number Contents 329 ---------- ---------------------- 330 7 Reserved (always zero) 331 6 Reserved (always zero) 332 5 ... 3 Zero 333 2 ... 0 L' 334 */ 335 336 static void btstack_crypto_ccm_setup_a_i(btstack_crypto_ccm_t * btstack_crypto_ccm, uint16_t counter){ 337 btstack_crypto_ccm_s[0] = 1; // L' = L - 1 338 memcpy(&btstack_crypto_ccm_s[1], btstack_crypto_ccm->nonce, 13); 339 big_endian_store_16(btstack_crypto_ccm_s, 14, counter); 340 } 341 342 /* 343 The first step is to compute the authentication field T. This is 344 done using CBC-MAC [MAC]. We first define a sequence of blocks B_0, 345 B_1, ..., B_n and then apply CBC-MAC to these blocks. 346 347 The first block B_0 is formatted as follows, where l(m) is encoded in 348 most-significant-byte first order: 349 350 Octet Number Contents 351 ------------ --------- 352 0 Flags 353 1 ... 15-L Nonce N 354 16-L ... 15 l(m) 355 356 Within the first block B_0, the Flags field is formatted as follows: 357 358 Bit Number Contents 359 ---------- ---------------------- 360 7 Reserved (always zero) 361 6 Adata 362 5 ... 3 M' 363 2 ... 0 L' 364 */ 365 366 static void btstack_crypto_ccm_setup_b_0(btstack_crypto_ccm_t * btstack_crypto_ccm, uint8_t * b0){ 367 b0[0] = (3 << 3) | 1 ; // Adata = 0, M' = (M-2)/2, L' = L - 1 368 memcpy(&b0[1], btstack_crypto_ccm->nonce, 13); 369 big_endian_store_16(b0, 14, btstack_crypto_ccm->message_len); 370 } 371 #endif 372 373 #ifdef ENABLE_ECC_P256 374 375 static void btstack_crypto_log_ec_publickey(const uint8_t * ec_q){ 376 log_info("Elliptic curve: X"); 377 log_info_hexdump(&ec_q[0],32); 378 log_info("Elliptic curve: Y"); 379 log_info_hexdump(&ec_q[32],32); 380 } 381 382 #if (defined(USE_MICRO_ECC_P256) && !defined(WICED_VERSION)) || defined(USE_MBEDTLS_ECC_P256) 383 // @return OK 384 static int sm_generate_f_rng(unsigned char * buffer, unsigned size){ 385 if (btstack_crypto_ecc_p256_key_generation_state != ECC_P256_KEY_GENERATION_ACTIVE) return 0; 386 log_info("sm_generate_f_rng: size %u - offset %u", (int) size, btstack_crypto_ecc_p256_random_offset); 387 while (size) { 388 *buffer++ = btstack_crypto_ecc_p256_random[btstack_crypto_ecc_p256_random_offset++]; 389 size--; 390 } 391 return 1; 392 } 393 #endif 394 #ifdef USE_MBEDTLS_ECC_P256 395 // @return error - just wrap sm_generate_f_rng 396 static int sm_generate_f_rng_mbedtls(void * context, unsigned char * buffer, size_t size){ 397 UNUSED(context); 398 return sm_generate_f_rng(buffer, size) == 0; 399 } 400 #endif /* USE_MBEDTLS_ECC_P256 */ 401 402 static void btstack_crypto_ecc_p256_generate_key_software(void){ 403 404 btstack_crypto_ecc_p256_random_offset = 0; 405 406 // generate EC key 407 #ifdef USE_MICRO_ECC_P256 408 409 #ifndef WICED_VERSION 410 log_info("set uECC RNG for initial key generation with 64 random bytes"); 411 // micro-ecc from WICED SDK uses its wiced_crypto_get_random by default - no need to set it 412 uECC_set_rng(&sm_generate_f_rng); 413 #endif /* WICED_VERSION */ 414 415 #if uECC_SUPPORTS_secp256r1 416 // standard version 417 uECC_make_key(btstack_crypto_ecc_p256_public_key, btstack_crypto_ecc_p256_d, uECC_secp256r1()); 418 419 // disable RNG again, as returning no randmon data lets shared key generation fail 420 log_info("disable uECC RNG in standard version after key generation"); 421 uECC_set_rng(NULL); 422 #else 423 // static version 424 uECC_make_key(btstack_crypto_ecc_p256_public_key, btstack_crypto_ecc_p256_d); 425 #endif 426 #endif /* USE_MICRO_ECC_P256 */ 427 428 #ifdef USE_MBEDTLS_ECC_P256 429 mbedtls_mpi d; 430 mbedtls_ecp_point P; 431 mbedtls_mpi_init(&d); 432 mbedtls_ecp_point_init(&P); 433 int res = mbedtls_ecp_gen_keypair(&mbedtls_ec_group, &d, &P, &sm_generate_f_rng_mbedtls, NULL); 434 log_info("gen keypair %x", res); 435 mbedtls_mpi_write_binary(&P.X, &btstack_crypto_ecc_p256_public_key[0], 32); 436 mbedtls_mpi_write_binary(&P.Y, &btstack_crypto_ecc_p256_public_key[32], 32); 437 mbedtls_mpi_write_binary(&d, btstack_crypto_ecc_p256_d, 32); 438 mbedtls_ecp_point_free(&P); 439 mbedtls_mpi_free(&d); 440 #endif /* USE_MBEDTLS_ECC_P256 */ 441 } 442 443 #ifdef USE_SOFTWARE_ECC_P256_IMPLEMENTATION 444 static void btstack_crypto_ecc_p256_calculate_dhkey_software(btstack_crypto_ecc_p256_t * btstack_crypto_ec_p192){ 445 memset(btstack_crypto_ec_p192->dhkey, 0, 32); 446 447 #ifdef USE_MICRO_ECC_P256 448 #if uECC_SUPPORTS_secp256r1 449 // standard version 450 uECC_shared_secret(btstack_crypto_ec_p192->public_key, btstack_crypto_ecc_p256_d, btstack_crypto_ec_p192->dhkey, uECC_secp256r1()); 451 #else 452 // static version 453 uECC_shared_secret(btstack_crypto_ec_p192->public_key, btstack_crypto_ecc_p256_d, btstack_crypto_ec_p192->dhkey); 454 #endif 455 #endif 456 457 #ifdef USE_MBEDTLS_ECC_P256 458 // da * Pb 459 mbedtls_mpi d; 460 mbedtls_ecp_point Q; 461 mbedtls_ecp_point DH; 462 mbedtls_mpi_init(&d); 463 mbedtls_ecp_point_init(&Q); 464 mbedtls_ecp_point_init(&DH); 465 mbedtls_mpi_read_binary(&d, btstack_crypto_ecc_p256_d, 32); 466 mbedtls_mpi_read_binary(&Q.X, &btstack_crypto_ec_p192->public_key[0] , 32); 467 mbedtls_mpi_read_binary(&Q.Y, &btstack_crypto_ec_p192->public_key[32], 32); 468 mbedtls_mpi_lset(&Q.Z, 1); 469 mbedtls_ecp_mul(&mbedtls_ec_group, &DH, &d, &Q, NULL, NULL); 470 mbedtls_mpi_write_binary(&DH.X, btstack_crypto_ec_p192->dhkey, 32); 471 mbedtls_ecp_point_free(&DH); 472 mbedtls_mpi_free(&d); 473 mbedtls_ecp_point_free(&Q); 474 #endif 475 476 log_info("dhkey"); 477 log_info_hexdump(btstack_crypto_ec_p192->dhkey, 32); 478 } 479 #endif 480 481 #endif 482 483 #ifdef USE_BTSTACK_AES128 484 // CCM not implemented using software AES128 yet 485 #else 486 487 static void btstack_crypto_ccm_calc_s0(btstack_crypto_ccm_t * btstack_crypto_ccm){ 488 btstack_crypto_ccm->state = CCM_W4_S0; 489 btstack_crypto_ccm_setup_a_i(btstack_crypto_ccm, 0); 490 btstack_crypto_aes128_start(btstack_crypto_ccm->key, btstack_crypto_ccm_s); 491 } 492 493 static void btstack_crypto_ccm_calc_sn(btstack_crypto_ccm_t * btstack_crypto_ccm){ 494 btstack_crypto_ccm->state = CCM_W4_SN; 495 btstack_crypto_ccm_setup_a_i(btstack_crypto_ccm, btstack_crypto_ccm->counter); 496 btstack_crypto_aes128_start(btstack_crypto_ccm->key, btstack_crypto_ccm_s); 497 } 498 499 static void btstack_crypto_ccm_calc_x1(btstack_crypto_ccm_t * btstack_crypto_ccm){ 500 uint8_t btstack_crypto_ccm_buffer[16]; 501 btstack_crypto_ccm->state = CCM_W4_X1; 502 btstack_crypto_ccm_setup_b_0(btstack_crypto_ccm, btstack_crypto_ccm_buffer); 503 btstack_crypto_aes128_start(btstack_crypto_ccm->key, btstack_crypto_ccm_buffer); 504 } 505 506 static void btstack_crypto_ccm_calc_xn(btstack_crypto_ccm_t * btstack_crypto_ccm, const uint8_t * plaintext){ 507 int i; 508 int bytes_to_decrypt; 509 uint8_t btstack_crypto_ccm_buffer[16]; 510 btstack_crypto_ccm->state = CCM_W4_XN; 511 bytes_to_decrypt = btstack_min(btstack_crypto_ccm->block_len, 16); 512 i = 0; 513 while (i < bytes_to_decrypt){ 514 btstack_crypto_ccm_buffer[i] = btstack_crypto_ccm->x_i[i] ^ plaintext[i]; 515 i++; 516 } 517 memcpy(&btstack_crypto_ccm_buffer[i], &btstack_crypto_ccm->x_i[i], 16 - bytes_to_decrypt); 518 btstack_crypto_aes128_start(btstack_crypto_ccm->key, btstack_crypto_ccm_buffer); 519 } 520 #endif 521 522 static void btstack_crypto_ccm_handle_s0(btstack_crypto_ccm_t * btstack_crypto_ccm, const uint8_t * data){ 523 // data is little-endian, flip on the fly 524 int i; 525 for (i=0;i<16;i++){ 526 btstack_crypto_ccm->x_i[i] = btstack_crypto_ccm->x_i[i] ^ data[15-i]; 527 } 528 btstack_crypto_done(&btstack_crypto_ccm->btstack_crypto); 529 } 530 531 static void btstack_crypto_ccm_handle_sn(btstack_crypto_ccm_t * btstack_crypto_ccm, const uint8_t * data){ 532 // data is little-endian, flip on the fly 533 int i; 534 uint16_t bytes_to_process = btstack_min(btstack_crypto_ccm->block_len, 16); 535 for (i=0;i<bytes_to_process;i++){ 536 btstack_crypto_ccm->output[i] = btstack_crypto_ccm->input[i] ^ data[15-i]; 537 } 538 } 539 540 static void btstack_crypto_ccm_next_block(btstack_crypto_ccm_t * btstack_crypto_ccm, btstack_crypto_ccm_state_t state_when_done){ 541 uint16_t bytes_to_process = btstack_min(btstack_crypto_ccm->block_len, 16); 542 // next block 543 btstack_crypto_ccm->counter++; 544 btstack_crypto_ccm->input += bytes_to_process; 545 btstack_crypto_ccm->output += bytes_to_process; 546 btstack_crypto_ccm->block_len -= bytes_to_process; 547 if (btstack_crypto_ccm->block_len == 0){ 548 btstack_crypto_ccm->state = CCM_CALCULATE_S0; 549 } 550 else { 551 btstack_crypto_ccm->state = state_when_done; 552 } 553 } 554 555 static void btstack_crypto_run(void){ 556 557 btstack_crypto_aes128_t * btstack_crypto_aes128; 558 btstack_crypto_ccm_t * btstack_crypto_ccm; 559 btstack_crypto_aes128_cmac_t * btstack_crypto_cmac; 560 #ifdef ENABLE_ECC_P256 561 btstack_crypto_ecc_p256_t * btstack_crypto_ec_p192; 562 #endif 563 564 // stack up and running? 565 if (hci_get_state() != HCI_STATE_WORKING) return; 566 567 // already active? 568 if (btstack_crypto_wait_for_hci_result) return; 569 570 // anything to do? 571 if (btstack_linked_list_empty(&btstack_crypto_operations)) return; 572 573 // can send a command? 574 if (!hci_can_send_command_packet_now()) return; 575 576 btstack_crypto_t * btstack_crypto = (btstack_crypto_t*) btstack_linked_list_get_first_item(&btstack_crypto_operations); 577 switch (btstack_crypto->operation){ 578 case BTSTACK_CRYPTO_RANDOM: 579 btstack_crypto_wait_for_hci_result = 1; 580 hci_send_cmd(&hci_le_rand); 581 break; 582 case BTSTACK_CRYPTO_AES128: 583 btstack_crypto_aes128 = (btstack_crypto_aes128_t *) btstack_crypto; 584 #ifdef USE_BTSTACK_AES128 585 btstack_aes128_calc(btstack_crypto_aes128->key, btstack_crypto_aes128->plaintext, btstack_crypto_aes128->ciphertext); 586 btstack_crypto_done(btstack_crypto); 587 #else 588 btstack_crypto_aes128_start(btstack_crypto_aes128->key, btstack_crypto_aes128->plaintext); 589 #endif 590 break; 591 case BTSTACK_CRYPTO_CMAC_MESSAGE: 592 case BTSTACK_CRYPTO_CMAC_GENERATOR: 593 btstack_crypto_wait_for_hci_result = 1; 594 btstack_crypto_cmac = (btstack_crypto_aes128_cmac_t *) btstack_crypto; 595 if (btstack_crypto_cmac_state == CMAC_IDLE){ 596 btstack_crypto_cmac_start(btstack_crypto_cmac); 597 } else { 598 btstack_crypto_cmac_handle_aes_engine_ready(btstack_crypto_cmac); 599 } 600 break; 601 602 case BTSTACK_CRYPTO_CCM_ENCRYPT_BLOCK: 603 case BTSTACK_CRYPTO_CCM_DECRYPT_BLOCK: 604 #ifdef USE_BTSTACK_AES128 605 UNUSED(btstack_crypto_ccm); 606 log_error("ccm not implemented for software aes128 yet"); 607 #else 608 btstack_crypto_ccm = (btstack_crypto_ccm_t *) btstack_crypto; 609 switch (btstack_crypto_ccm->state){ 610 case CCM_CALCULATE_X1: 611 btstack_crypto_ccm_calc_x1(btstack_crypto_ccm); 612 break; 613 case CCM_CALCULATE_S0: 614 btstack_crypto_ccm_calc_s0(btstack_crypto_ccm); 615 break; 616 case CCM_CALCULATE_SN: 617 btstack_crypto_ccm_calc_sn(btstack_crypto_ccm); 618 break; 619 case CCM_CALCULATE_XN: 620 btstack_crypto_ccm_calc_xn(btstack_crypto_ccm, btstack_crypto->operation == BTSTACK_CRYPTO_CCM_ENCRYPT_BLOCK ? btstack_crypto_ccm->input : btstack_crypto_ccm->output); 621 break; 622 default: 623 break; 624 } 625 #endif 626 break; 627 628 #ifdef ENABLE_ECC_P256 629 case BTSTACK_CRYPTO_ECC_P256_GENERATE_KEY: 630 btstack_crypto_ec_p192 = (btstack_crypto_ecc_p256_t *) btstack_crypto; 631 switch (btstack_crypto_ecc_p256_key_generation_state){ 632 case ECC_P256_KEY_GENERATION_DONE: 633 // done 634 btstack_crypto_log_ec_publickey(btstack_crypto_ecc_p256_public_key); 635 memcpy(btstack_crypto_ec_p192->public_key, btstack_crypto_ecc_p256_public_key, 64); 636 btstack_linked_list_pop(&btstack_crypto_operations); 637 (*btstack_crypto_ec_p192->btstack_crypto.context_callback.callback)(btstack_crypto_ec_p192->btstack_crypto.context_callback.context); 638 break; 639 case ECC_P256_KEY_GENERATION_IDLE: 640 #ifdef USE_SOFTWARE_ECC_P256_IMPLEMENTATION 641 log_info("start ecc random"); 642 btstack_crypto_ecc_p256_key_generation_state = ECC_P256_KEY_GENERATION_GENERATING_RANDOM; 643 btstack_crypto_ecc_p256_random_offset = 0; 644 btstack_crypto_wait_for_hci_result = 1; 645 hci_send_cmd(&hci_le_rand); 646 #else 647 btstack_crypto_ecc_p256_key_generation_state = ECC_P256_KEY_GENERATION_W4_KEY; 648 btstack_crypto_wait_for_hci_result = 1; 649 hci_send_cmd(&hci_le_read_local_p256_public_key); 650 #endif 651 break; 652 #ifdef USE_SOFTWARE_ECC_P256_IMPLEMENTATION 653 case ECC_P256_KEY_GENERATION_GENERATING_RANDOM: 654 log_info("more ecc random"); 655 btstack_crypto_wait_for_hci_result = 1; 656 hci_send_cmd(&hci_le_rand); 657 break; 658 #endif 659 default: 660 break; 661 } 662 break; 663 case BTSTACK_CRYPTO_ECC_P256_CALCULATE_DHKEY: 664 btstack_crypto_ec_p192 = (btstack_crypto_ecc_p256_t *) btstack_crypto; 665 #ifdef USE_SOFTWARE_ECC_P256_IMPLEMENTATION 666 btstack_crypto_ecc_p256_calculate_dhkey_software(btstack_crypto_ec_p192); 667 // done 668 btstack_linked_list_pop(&btstack_crypto_operations); 669 (*btstack_crypto_ec_p192->btstack_crypto.context_callback.callback)(btstack_crypto_ec_p192->btstack_crypto.context_callback.context); 670 #else 671 btstack_crypto_wait_for_hci_result = 1; 672 hci_send_cmd(&hci_le_generate_dhkey, &btstack_crypto_ec_p192->public_key[0], &btstack_crypto_ec_p192->public_key[32]); 673 #endif 674 break; 675 676 #endif /* ENABLE_ECC_P256 */ 677 678 default: 679 break; 680 } 681 } 682 683 static void btstack_crypto_handle_random_data(const uint8_t * data, uint16_t len){ 684 btstack_crypto_random_t * btstack_crypto_random; 685 btstack_crypto_t * btstack_crypto = (btstack_crypto_t*) btstack_linked_list_get_first_item(&btstack_crypto_operations); 686 uint16_t bytes_to_copy; 687 if (!btstack_crypto) return; 688 switch (btstack_crypto->operation){ 689 case BTSTACK_CRYPTO_RANDOM: 690 btstack_crypto_random = (btstack_crypto_random_t*) btstack_crypto; 691 bytes_to_copy = btstack_min(btstack_crypto_random->size, len); 692 memcpy(btstack_crypto_random->buffer, data, bytes_to_copy); 693 btstack_crypto_random->buffer += bytes_to_copy; 694 btstack_crypto_random->size -= bytes_to_copy; 695 // data processed, more? 696 if (!btstack_crypto_random->size) { 697 // done 698 btstack_linked_list_pop(&btstack_crypto_operations); 699 (*btstack_crypto_random->btstack_crypto.context_callback.callback)(btstack_crypto_random->btstack_crypto.context_callback.context); 700 } 701 break; 702 #ifdef ENABLE_ECC_P256 703 case BTSTACK_CRYPTO_ECC_P256_GENERATE_KEY: 704 memcpy(&btstack_crypto_ecc_p256_random[btstack_crypto_ecc_p256_random_len], data, 8); 705 btstack_crypto_ecc_p256_random_len += 8; 706 if (btstack_crypto_ecc_p256_random_len >= 64) { 707 btstack_crypto_ecc_p256_key_generation_state = ECC_P256_KEY_GENERATION_ACTIVE; 708 btstack_crypto_ecc_p256_generate_key_software(); 709 btstack_crypto_ecc_p256_key_generation_state = ECC_P256_KEY_GENERATION_DONE; 710 } 711 break; 712 #endif 713 default: 714 break; 715 } 716 // more work? 717 btstack_crypto_run(); 718 } 719 720 static void btstack_crypto_handle_encryption_result(const uint8_t * data){ 721 btstack_crypto_aes128_t * btstack_crypto_aes128; 722 btstack_crypto_aes128_cmac_t * btstack_crypto_cmac; 723 btstack_crypto_ccm_t * btstack_crypto_ccm; 724 uint8_t result[16]; 725 726 btstack_crypto_t * btstack_crypto = (btstack_crypto_t*) btstack_linked_list_get_first_item(&btstack_crypto_operations); 727 if (!btstack_crypto) return; 728 switch (btstack_crypto->operation){ 729 case BTSTACK_CRYPTO_AES128: 730 btstack_crypto_aes128 = (btstack_crypto_aes128_t*) btstack_linked_list_get_first_item(&btstack_crypto_operations); 731 reverse_128(data, btstack_crypto_aes128->ciphertext); 732 btstack_crypto_done(btstack_crypto); 733 break; 734 case BTSTACK_CRYPTO_CMAC_GENERATOR: 735 case BTSTACK_CRYPTO_CMAC_MESSAGE: 736 btstack_crypto_cmac = (btstack_crypto_aes128_cmac_t*) btstack_linked_list_get_first_item(&btstack_crypto_operations); 737 reverse_128(data, result); 738 btstack_crypto_cmac_handle_encryption_result(btstack_crypto_cmac, result); 739 break; 740 case BTSTACK_CRYPTO_CCM_ENCRYPT_BLOCK: 741 btstack_crypto_ccm = (btstack_crypto_ccm_t*) btstack_linked_list_get_first_item(&btstack_crypto_operations); 742 switch (btstack_crypto_ccm->state){ 743 case CCM_W4_X1: 744 reverse_128(data, btstack_crypto_ccm->x_i); 745 btstack_crypto_ccm->state = CCM_CALCULATE_XN; 746 break; 747 case CCM_W4_XN: 748 reverse_128(data, btstack_crypto_ccm->x_i); 749 btstack_crypto_ccm->state = CCM_CALCULATE_SN; 750 break; 751 case CCM_W4_S0: 752 btstack_crypto_ccm_handle_s0(btstack_crypto_ccm, data); 753 break; 754 case CCM_W4_SN: 755 btstack_crypto_ccm_handle_sn(btstack_crypto_ccm, data); 756 btstack_crypto_ccm_next_block(btstack_crypto_ccm, CCM_CALCULATE_XN); 757 break; 758 default: 759 break; 760 } 761 break; 762 case BTSTACK_CRYPTO_CCM_DECRYPT_BLOCK: 763 btstack_crypto_ccm = (btstack_crypto_ccm_t*) btstack_linked_list_get_first_item(&btstack_crypto_operations); 764 switch (btstack_crypto_ccm->state){ 765 case CCM_W4_X1: 766 reverse_128(data, btstack_crypto_ccm->x_i); 767 btstack_crypto_ccm->state = CCM_CALCULATE_SN; 768 break; 769 case CCM_W4_XN: 770 reverse_128(data, btstack_crypto_ccm->x_i); 771 btstack_crypto_ccm_next_block(btstack_crypto_ccm, CCM_CALCULATE_SN); 772 break; 773 case CCM_W4_S0: 774 btstack_crypto_ccm_handle_s0(btstack_crypto_ccm, data); 775 break; 776 case CCM_W4_SN: 777 btstack_crypto_ccm_handle_sn(btstack_crypto_ccm, data); 778 btstack_crypto_ccm->state = CCM_CALCULATE_XN; 779 break; 780 default: 781 break; 782 } 783 break; 784 default: 785 break; 786 } 787 } 788 789 static void btstack_crypto_event_handler(uint8_t packet_type, uint16_t cid, uint8_t *packet, uint16_t size){ 790 UNUSED(cid); // ok: there is no channel 791 UNUSED(size); // ok: fixed format events read from HCI buffer 792 793 #ifdef ENABLE_ECC_P256 794 #ifndef USE_SOFTWARE_ECC_P256_IMPLEMENTATION 795 btstack_crypto_ecc_p256_t * btstack_crypto_ec_p192; 796 #endif 797 #endif 798 799 if (packet_type != HCI_EVENT_PACKET) return; 800 801 switch (hci_event_packet_get_type(packet)){ 802 case HCI_EVENT_COMMAND_COMPLETE: 803 if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_encrypt)){ 804 if (hci_get_state() != HCI_STATE_WORKING) return; 805 if (!btstack_crypto_wait_for_hci_result) return; 806 btstack_crypto_wait_for_hci_result = 0; 807 btstack_crypto_handle_encryption_result(&packet[6]); 808 } 809 if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_rand)){ 810 if (hci_get_state() != HCI_STATE_WORKING) return; 811 if (!btstack_crypto_wait_for_hci_result) return; 812 btstack_crypto_wait_for_hci_result = 0; 813 btstack_crypto_handle_random_data(&packet[6], 8); 814 } 815 if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_supported_commands)){ 816 int ecdh_operations_supported = (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+34] & 0x06) == 0x06; 817 log_info("controller supports ECDH operation: %u", ecdh_operations_supported); 818 #ifdef ENABLE_ECC_P256 819 #ifndef USE_SOFTWARE_ECC_P256_IMPLEMENTATION 820 if (!ecdh_operations_supported){ 821 // mbedTLS can also be used if already available (and malloc is supported) 822 log_error("ECC-P256 support enabled, but HCI Controller doesn't support it. Please add ENABLE_MICRO_ECC_FOR_LE_SECURE_CONNECTIONS to btstack_config.h"); 823 } 824 #endif 825 #endif 826 } 827 break; 828 829 #ifdef ENABLE_ECC_P256 830 #ifndef USE_SOFTWARE_ECC_P256_IMPLEMENTATION 831 case HCI_EVENT_LE_META: 832 btstack_crypto_ec_p192 = (btstack_crypto_ecc_p256_t*) btstack_linked_list_get_first_item(&btstack_crypto_operations); 833 if (!btstack_crypto_ec_p192) break; 834 switch (hci_event_le_meta_get_subevent_code(packet)){ 835 case HCI_SUBEVENT_LE_READ_LOCAL_P256_PUBLIC_KEY_COMPLETE: 836 if (btstack_crypto_ec_p192->btstack_crypto.operation != BTSTACK_CRYPTO_ECC_P256_GENERATE_KEY) break; 837 if (!btstack_crypto_wait_for_hci_result) return; 838 btstack_crypto_wait_for_hci_result = 0; 839 if (hci_subevent_le_read_local_p256_public_key_complete_get_status(packet)){ 840 log_error("Read Local P256 Public Key failed"); 841 } 842 hci_subevent_le_read_local_p256_public_key_complete_get_dhkey_x(packet, &btstack_crypto_ecc_p256_public_key[0]); 843 hci_subevent_le_read_local_p256_public_key_complete_get_dhkey_y(packet, &btstack_crypto_ecc_p256_public_key[32]); 844 btstack_crypto_ecc_p256_key_generation_state = ECC_P256_KEY_GENERATION_DONE; 845 break; 846 case HCI_SUBEVENT_LE_GENERATE_DHKEY_COMPLETE: 847 if (btstack_crypto_ec_p192->btstack_crypto.operation != BTSTACK_CRYPTO_ECC_P256_CALCULATE_DHKEY) break; 848 if (!btstack_crypto_wait_for_hci_result) return; 849 btstack_crypto_wait_for_hci_result = 0; 850 if (hci_subevent_le_generate_dhkey_complete_get_status(packet)){ 851 log_error("Generate DHKEY failed -> abort"); 852 } 853 hci_subevent_le_generate_dhkey_complete_get_dhkey(packet, btstack_crypto_ec_p192->dhkey); 854 // done 855 btstack_linked_list_pop(&btstack_crypto_operations); 856 (*btstack_crypto_ec_p192->btstack_crypto.context_callback.callback)(btstack_crypto_ec_p192->btstack_crypto.context_callback.context); 857 break; 858 default: 859 break; 860 } 861 break; 862 #endif 863 #endif 864 default: 865 break; 866 } 867 868 // try processing 869 btstack_crypto_run(); 870 } 871 872 void btstack_crypto_init(void){ 873 if (btstack_crypto_initialized) return; 874 btstack_crypto_initialized = 1; 875 876 // register with HCI 877 hci_event_callback_registration.callback = &btstack_crypto_event_handler; 878 hci_add_event_handler(&hci_event_callback_registration); 879 880 #ifdef USE_MBEDTLS_ECC_P256 881 mbedtls_ecp_group_init(&mbedtls_ec_group); 882 mbedtls_ecp_group_load(&mbedtls_ec_group, MBEDTLS_ECP_DP_SECP256R1); 883 #endif 884 } 885 886 void btstack_crypto_random_generate(btstack_crypto_random_t * request, uint8_t * buffer, uint16_t size, void (* callback)(void * arg), void * callback_arg){ 887 request->btstack_crypto.context_callback.callback = callback; 888 request->btstack_crypto.context_callback.context = callback_arg; 889 request->btstack_crypto.operation = BTSTACK_CRYPTO_RANDOM; 890 request->buffer = buffer; 891 request->size = size; 892 btstack_linked_list_add_tail(&btstack_crypto_operations, (btstack_linked_item_t*) request); 893 btstack_crypto_run(); 894 } 895 896 void btstack_crypto_aes128_encrypt(btstack_crypto_aes128_t * request, const uint8_t * key, const uint8_t * plaintext, uint8_t * ciphertext, void (* callback)(void * arg), void * callback_arg){ 897 request->btstack_crypto.context_callback.callback = callback; 898 request->btstack_crypto.context_callback.context = callback_arg; 899 request->btstack_crypto.operation = BTSTACK_CRYPTO_AES128; 900 request->key = key; 901 request->plaintext = plaintext; 902 request->ciphertext = ciphertext; 903 btstack_linked_list_add_tail(&btstack_crypto_operations, (btstack_linked_item_t*) request); 904 btstack_crypto_run(); 905 } 906 907 void btstack_crypto_aes128_cmac_generator(btstack_crypto_aes128_cmac_t * request, const uint8_t * key, uint16_t size, uint8_t (*get_byte_callback)(uint16_t pos), uint8_t * hash, void (* callback)(void * arg), void * callback_arg){ 908 request->btstack_crypto.context_callback.callback = callback; 909 request->btstack_crypto.context_callback.context = callback_arg; 910 request->btstack_crypto.operation = BTSTACK_CRYPTO_CMAC_GENERATOR; 911 request->key = key; 912 request->size = size; 913 request->data.get_byte_callback = get_byte_callback; 914 request->hash = hash; 915 btstack_linked_list_add_tail(&btstack_crypto_operations, (btstack_linked_item_t*) request); 916 btstack_crypto_run(); 917 } 918 919 void btstack_crypto_aes128_cmac_message(btstack_crypto_aes128_cmac_t * request, const uint8_t * key, uint16_t size, const uint8_t * message, uint8_t * hash, void (* callback)(void * arg), void * callback_arg){ 920 request->btstack_crypto.context_callback.callback = callback; 921 request->btstack_crypto.context_callback.context = callback_arg; 922 request->btstack_crypto.operation = BTSTACK_CRYPTO_CMAC_MESSAGE; 923 request->key = key; 924 request->size = size; 925 request->data.message = message; 926 request->hash = hash; 927 btstack_linked_list_add_tail(&btstack_crypto_operations, (btstack_linked_item_t*) request); 928 btstack_crypto_run(); 929 } 930 931 void btstack_crypto_aes128_cmac_zero(btstack_crypto_aes128_cmac_t * request, uint16_t len, const uint8_t * message, uint8_t * hash, void (* callback)(void * arg), void * callback_arg){ 932 request->btstack_crypto.context_callback.callback = callback; 933 request->btstack_crypto.context_callback.context = callback_arg; 934 request->btstack_crypto.operation = BTSTACK_CRYPTO_CMAC_MESSAGE; 935 request->key = zero; 936 request->size = len; 937 request->data.message = message; 938 request->hash = hash; 939 btstack_linked_list_add_tail(&btstack_crypto_operations, (btstack_linked_item_t*) request); 940 btstack_crypto_run(); 941 } 942 943 #ifdef ENABLE_ECC_P256 944 void btstack_crypto_ecc_p256_generate_key(btstack_crypto_ecc_p256_t * request, uint8_t * public_key, void (* callback)(void * arg), void * callback_arg){ 945 request->btstack_crypto.context_callback.callback = callback; 946 request->btstack_crypto.context_callback.context = callback_arg; 947 request->btstack_crypto.operation = BTSTACK_CRYPTO_ECC_P256_GENERATE_KEY; 948 request->public_key = public_key; 949 btstack_linked_list_add_tail(&btstack_crypto_operations, (btstack_linked_item_t*) request); 950 btstack_crypto_run(); 951 } 952 953 void btstack_crypto_ecc_p256_calculate_dhkey(btstack_crypto_ecc_p256_t * request, const uint8_t * public_key, uint8_t * dhkey, void (* callback)(void * arg), void * callback_arg){ 954 request->btstack_crypto.context_callback.callback = callback; 955 request->btstack_crypto.context_callback.context = callback_arg; 956 request->btstack_crypto.operation = BTSTACK_CRYPTO_ECC_P256_CALCULATE_DHKEY; 957 request->public_key = (uint8_t *) public_key; 958 request->dhkey = dhkey; 959 btstack_linked_list_add_tail(&btstack_crypto_operations, (btstack_linked_item_t*) request); 960 btstack_crypto_run(); 961 } 962 963 int btstack_crypto_ecc_p256_validate_public_key(const uint8_t * public_key){ 964 965 // validate public key using micro-ecc 966 int err = 0; 967 968 #ifdef USE_MICRO_ECC_P256 969 #if uECC_SUPPORTS_secp256r1 970 // standard version 971 err = uECC_valid_public_key(public_key, uECC_secp256r1()) == 0; 972 #else 973 // static version 974 err = uECC_valid_public_key(public_key) == 0; 975 #endif 976 #endif 977 978 #ifdef USE_MBEDTLS_ECC_P256 979 mbedtls_ecp_point Q; 980 mbedtls_ecp_point_init( &Q ); 981 mbedtls_mpi_read_binary(&Q.X, &public_key[0], 32); 982 mbedtls_mpi_read_binary(&Q.Y, &public_key[32], 32); 983 mbedtls_mpi_lset(&Q.Z, 1); 984 err = mbedtls_ecp_check_pubkey(&mbedtls_ec_group, &Q); 985 mbedtls_ecp_point_free( & Q); 986 #endif 987 988 if (err){ 989 log_error("public key invalid %x", err); 990 } 991 return err; 992 } 993 #endif 994 995 void btstack_crypo_ccm_init(btstack_crypto_ccm_t * request, const uint8_t * key, const uint8_t * nonce, uint16_t message_len){ 996 request->key = key; 997 request->nonce = nonce; 998 request->message_len = message_len; 999 request->counter = 1; 1000 } 1001 1002 void btstack_crypo_ccm_get_authentication_value(btstack_crypto_ccm_t * request, uint8_t * authentication_value){ 1003 memcpy(authentication_value, request->x_i, 8); 1004 } 1005 1006 void btstack_crypto_ccm_encrypt_block(btstack_crypto_ccm_t * request, uint16_t block_len, const uint8_t * plaintext, uint8_t * ciphertext, void (* callback)(void * arg), void * callback_arg){ 1007 request->btstack_crypto.context_callback.callback = callback; 1008 request->btstack_crypto.context_callback.context = callback_arg; 1009 request->btstack_crypto.operation = BTSTACK_CRYPTO_CCM_ENCRYPT_BLOCK; 1010 request->state = CCM_CALCULATE_X1; 1011 request->block_len = block_len; 1012 request->input = plaintext; 1013 request->output = ciphertext; 1014 btstack_linked_list_add_tail(&btstack_crypto_operations, (btstack_linked_item_t*) request); 1015 btstack_crypto_run(); 1016 } 1017 1018 void btstack_crypto_ccm_decrypt_block(btstack_crypto_ccm_t * request, uint16_t block_len, const uint8_t * ciphertext, uint8_t * plaintext, void (* callback)(void * arg), void * callback_arg){ 1019 request->btstack_crypto.context_callback.callback = callback; 1020 request->btstack_crypto.context_callback.context = callback_arg; 1021 request->btstack_crypto.operation = BTSTACK_CRYPTO_CCM_DECRYPT_BLOCK; 1022 request->state = CCM_CALCULATE_X1; 1023 request->block_len = block_len; 1024 request->input = ciphertext; 1025 request->output = plaintext; 1026 btstack_linked_list_add_tail(&btstack_crypto_operations, (btstack_linked_item_t*) request); 1027 btstack_crypto_run(); 1028 } 1029 1030