1 /* 2 * Copyright (C) 2014 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 * 4. Any redistribution, use, or modification is done solely for 17 * personal benefit and not for any commercial purpose or for 18 * monetary gain. 19 * 20 * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 23 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS 24 * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 26 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 27 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 28 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 29 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF 30 * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * Please inquire about commercial licensing options at 34 * [email protected] 35 * 36 */ 37 38 #define __BTSTACK_FILE__ "mesh_transport.c" 39 40 #include <stdio.h> 41 #include <stdlib.h> 42 #include <string.h> 43 #include "mesh/beacon.h" 44 #include "mesh/mesh_lower_transport.h" 45 #include "mesh/mesh_upper_transport.h" 46 #include "btstack_util.h" 47 #include "btstack_memory.h" 48 #include "mesh_peer.h" 49 #include "mesh_keys.h" 50 #include "mesh_virtual_addresses.h" 51 #include "mesh_iv_index_seq_number.h" 52 53 static uint16_t primary_element_address; 54 55 static void (*higher_layer_handler)( mesh_transport_callback_type_t callback_type, mesh_transport_status_t status, mesh_pdu_t * pdu); 56 57 static void mesh_print_hex(const char * name, const uint8_t * data, uint16_t len){ 58 printf("%-20s ", name); 59 printf_hexdump(data, len); 60 } 61 // static void mesh_print_x(const char * name, uint32_t value){ 62 // printf("%20s: 0x%x", name, (int) value); 63 // } 64 65 66 // combined key x address iterator for upper transport decryption 67 68 typedef struct { 69 // state 70 mesh_transport_key_iterator_t key_it; 71 mesh_virtual_address_iterator_t address_it; 72 // elements 73 const mesh_transport_key_t * key; 74 const mesh_virtual_address_t * address; 75 // address - might be virtual 76 uint16_t dst; 77 // key info 78 } mesh_transport_key_and_virtual_address_iterator_t; 79 80 static void mesh_transport_key_and_virtual_address_iterator_init(mesh_transport_key_and_virtual_address_iterator_t *it, 81 uint16_t dst, uint16_t netkey_index, uint8_t akf, 82 uint8_t aid) { 83 printf("KEY_INIT: dst %04x, akf %x, aid %x\n", dst, akf, aid); 84 // config 85 it->dst = dst; 86 // init elements 87 it->key = NULL; 88 it->address = NULL; 89 // init element iterators 90 mesh_transport_key_aid_iterator_init(&it->key_it, netkey_index, akf, aid); 91 // init address iterator 92 if (mesh_network_address_virtual(it->dst)){ 93 mesh_virtual_address_iterator_init(&it->address_it, dst); 94 // get first key 95 if (mesh_transport_key_aid_iterator_has_more(&it->key_it)) { 96 it->key = mesh_transport_key_aid_iterator_get_next(&it->key_it); 97 } 98 } 99 } 100 101 // cartesian product: keys x addressses 102 static int mesh_transport_key_and_virtual_address_iterator_has_more(mesh_transport_key_and_virtual_address_iterator_t * it){ 103 if (mesh_network_address_virtual(it->dst)) { 104 // find next valid entry 105 while (1){ 106 if (mesh_virtual_address_iterator_has_more(&it->address_it)) return 1; 107 if (!mesh_transport_key_aid_iterator_has_more(&it->key_it)) return 0; 108 // get next key 109 it->key = mesh_transport_key_aid_iterator_get_next(&it->key_it); 110 mesh_virtual_address_iterator_init(&it->address_it, it->dst); 111 } 112 } else { 113 return mesh_transport_key_aid_iterator_has_more(&it->key_it); 114 } 115 } 116 117 static void mesh_transport_key_and_virtual_address_iterator_next(mesh_transport_key_and_virtual_address_iterator_t * it){ 118 if (mesh_network_address_virtual(it->dst)) { 119 it->address = mesh_virtual_address_iterator_get_next(&it->address_it); 120 } else { 121 it->key = mesh_transport_key_aid_iterator_get_next(&it->key_it); 122 } 123 } 124 125 // UPPER TRANSPORT 126 127 // stub lower transport 128 129 static void mesh_upper_transport_validate_unsegmented_message(mesh_network_pdu_t * network_pdu); 130 static void mesh_upper_transport_validate_segmented_message(mesh_transport_pdu_t * transport_pdu); 131 132 static void mesh_transport_run(void); 133 134 static int crypto_active; 135 static mesh_network_pdu_t * network_pdu_in_validation; 136 static mesh_transport_pdu_t * transport_pdu_in_validation; 137 static uint8_t application_nonce[13]; 138 static btstack_crypto_ccm_t ccm; 139 static mesh_transport_key_and_virtual_address_iterator_t mesh_transport_key_it; 140 141 // upper transport callbacks - in access layer 142 static void (*mesh_access_message_handler)(mesh_pdu_t * pdu); 143 static void (*mesh_control_message_handler)(mesh_pdu_t * pdu); 144 145 // unsegmented (network) and segmented (transport) control and access messages 146 static btstack_linked_list_t upper_transport_incoming; 147 148 149 void mesh_upper_unsegmented_control_message_received(mesh_network_pdu_t * network_pdu){ 150 uint8_t * lower_transport_pdu = mesh_network_pdu_data(network_pdu); 151 uint8_t opcode = lower_transport_pdu[0]; 152 if (mesh_control_message_handler){ 153 mesh_control_message_handler((mesh_pdu_t*) network_pdu); 154 } else { 155 printf("[!] Unhandled Control message with opcode %02x\n", opcode); 156 // done 157 mesh_lower_transport_message_processed_by_higher_layer((mesh_pdu_t *) network_pdu); 158 } 159 } 160 161 static void mesh_upper_transport_process_unsegmented_message_done(mesh_network_pdu_t *network_pdu){ 162 crypto_active = 0; 163 if (mesh_network_control(network_pdu)) { 164 mesh_lower_transport_message_processed_by_higher_layer((mesh_pdu_t *) network_pdu); 165 } else { 166 mesh_network_pdu_free(network_pdu); 167 mesh_lower_transport_message_processed_by_higher_layer((mesh_pdu_t *) network_pdu_in_validation); 168 network_pdu_in_validation = NULL; 169 } 170 mesh_transport_run(); 171 } 172 173 static void mesh_upper_transport_process_segmented_message_done(mesh_transport_pdu_t *transport_pdu){ 174 crypto_active = 0; 175 if (mesh_transport_ctl(transport_pdu)) { 176 mesh_lower_transport_message_processed_by_higher_layer((mesh_pdu_t *)transport_pdu); 177 } else { 178 mesh_transport_pdu_free(transport_pdu); 179 mesh_lower_transport_message_processed_by_higher_layer((mesh_pdu_t *)transport_pdu_in_validation); 180 transport_pdu_in_validation = NULL; 181 } 182 mesh_transport_run(); 183 } 184 185 static uint32_t iv_index_for_ivi_nid(uint8_t ivi_nid){ 186 // get IV Index and IVI 187 uint32_t iv_index = mesh_get_iv_index(); 188 int ivi = ivi_nid >> 7; 189 190 // if least significant bit differs, use previous IV Index 191 if ((iv_index & 1 ) ^ ivi){ 192 iv_index--; 193 } 194 return iv_index; 195 } 196 197 static void transport_unsegmented_setup_nonce(uint8_t * nonce, const mesh_network_pdu_t * network_pdu){ 198 nonce[1] = 0x00; // SZMIC if a Segmented Access message or 0 for all other message formats 199 memcpy(&nonce[2], &network_pdu->data[2], 7); 200 big_endian_store_32(nonce, 9, iv_index_for_ivi_nid(network_pdu->data[0])); 201 } 202 203 static void transport_segmented_setup_nonce(uint8_t * nonce, const mesh_transport_pdu_t * transport_pdu){ 204 nonce[1] = transport_pdu->transmic_len == 8 ? 0x80 : 0x00; 205 memcpy(&nonce[2], &transport_pdu->network_header[2], 7); 206 big_endian_store_32(nonce, 9, iv_index_for_ivi_nid(transport_pdu->network_header[0])); 207 } 208 209 static void transport_unsegmented_setup_application_nonce(uint8_t * nonce, const mesh_network_pdu_t * network_pdu){ 210 nonce[0] = 0x01; 211 transport_unsegmented_setup_nonce(nonce, network_pdu); 212 mesh_print_hex("AppNonce", nonce, 13); 213 } 214 215 static void transport_unsegmented_setup_device_nonce(uint8_t * nonce, const mesh_network_pdu_t * network_pdu){ 216 nonce[0] = 0x02; 217 transport_unsegmented_setup_nonce(nonce, network_pdu); 218 mesh_print_hex("DeviceNonce", nonce, 13); 219 } 220 221 static void transport_segmented_setup_application_nonce(uint8_t * nonce, const mesh_transport_pdu_t * transport_pdu){ 222 nonce[0] = 0x01; 223 transport_segmented_setup_nonce(nonce, transport_pdu); 224 mesh_print_hex("AppNonce", nonce, 13); 225 } 226 227 static void transport_segmented_setup_device_nonce(uint8_t * nonce, const mesh_transport_pdu_t * transport_pdu){ 228 nonce[0] = 0x02; 229 transport_segmented_setup_nonce(nonce, transport_pdu); 230 mesh_print_hex("DeviceNonce", nonce, 13); 231 } 232 233 static void mesh_upper_transport_validate_unsegmented_message_ccm(void * arg){ 234 mesh_network_pdu_t * network_pdu = (mesh_network_pdu_t *) arg; 235 236 uint8_t * lower_transport_pdu = mesh_network_pdu_data(network_pdu); 237 uint8_t trans_mic_len = 4; 238 239 // store TransMIC 240 uint8_t trans_mic[8]; 241 btstack_crypto_ccm_get_authentication_value(&ccm, trans_mic); 242 mesh_print_hex("TransMIC", trans_mic, trans_mic_len); 243 244 uint8_t * upper_transport_pdu = mesh_network_pdu_data(network_pdu) + 1; 245 uint8_t upper_transport_pdu_len = mesh_network_pdu_len(network_pdu) - 1; 246 247 mesh_print_hex("Decryted PDU", upper_transport_pdu, upper_transport_pdu_len - trans_mic_len); 248 249 if (memcmp(trans_mic, &upper_transport_pdu[upper_transport_pdu_len - trans_mic_len], trans_mic_len) == 0){ 250 printf("TransMIC matches\n"); 251 252 // remove TransMIC from payload 253 network_pdu->len -= trans_mic_len; 254 255 // if virtual address, update dst to pseudo_dst 256 if (mesh_network_address_virtual(mesh_network_dst(network_pdu))){ 257 big_endian_store_16(network_pdu->data, 7, mesh_transport_key_it.address->pseudo_dst); 258 } 259 260 // pass to upper layer 261 if (mesh_access_message_handler){ 262 mesh_access_message_handler((mesh_pdu_t*) network_pdu); 263 } else { 264 printf("[!] Unhandled Unsegmented Access message\n"); 265 // done 266 mesh_upper_transport_process_unsegmented_message_done(network_pdu); 267 } 268 269 printf("\n"); 270 } else { 271 uint8_t afk = lower_transport_pdu[0] & 0x40; 272 if (afk){ 273 printf("TransMIC does not match, try next key\n"); 274 mesh_upper_transport_validate_unsegmented_message(network_pdu); 275 } else { 276 printf("TransMIC does not match device key, done\n"); 277 // done 278 mesh_upper_transport_process_unsegmented_message_done(network_pdu); 279 } 280 } 281 } 282 283 static void mesh_upper_transport_validate_segmented_message_ccm(void * arg){ 284 mesh_transport_pdu_t * transport_pdu = (mesh_transport_pdu_t *) arg; 285 286 uint8_t * upper_transport_pdu = transport_pdu->data; 287 uint8_t upper_transport_pdu_len = transport_pdu->len - transport_pdu->transmic_len; 288 289 mesh_print_hex("Decrypted PDU", upper_transport_pdu, upper_transport_pdu_len); 290 291 // store TransMIC 292 uint8_t trans_mic[8]; 293 btstack_crypto_ccm_get_authentication_value(&ccm, trans_mic); 294 mesh_print_hex("TransMIC", trans_mic, transport_pdu->transmic_len); 295 296 if (memcmp(trans_mic, &upper_transport_pdu[upper_transport_pdu_len], transport_pdu->transmic_len) == 0){ 297 printf("TransMIC matches\n"); 298 299 // remove TransMIC from payload 300 transport_pdu->len -= transport_pdu->transmic_len; 301 302 // if virtual address, update dst to pseudo_dst 303 if (mesh_network_address_virtual(mesh_transport_dst(transport_pdu))){ 304 big_endian_store_16(transport_pdu->network_header, 7, mesh_transport_key_it.address->pseudo_dst); 305 } 306 307 // pass to upper layer 308 if (mesh_access_message_handler){ 309 mesh_access_message_handler((mesh_pdu_t*) transport_pdu); 310 } else { 311 printf("[!] Unhandled Segmented Access/Control message\n"); 312 // done 313 mesh_upper_transport_process_segmented_message_done(transport_pdu); 314 } 315 316 printf("\n"); 317 318 } else { 319 uint8_t akf = transport_pdu->akf_aid & 0x40; 320 if (akf){ 321 printf("TransMIC does not match, try next key\n"); 322 mesh_upper_transport_validate_segmented_message(transport_pdu); 323 } else { 324 printf("TransMIC does not match device key, done\n"); 325 // done 326 mesh_upper_transport_process_segmented_message_done(transport_pdu); 327 } 328 } 329 } 330 331 void mesh_upper_transport_message_processed_by_higher_layer(mesh_pdu_t * pdu){ 332 crypto_active = 0; 333 switch (pdu->pdu_type){ 334 case MESH_PDU_TYPE_NETWORK: 335 mesh_upper_transport_process_unsegmented_message_done((mesh_network_pdu_t *) pdu); 336 break; 337 case MESH_PDU_TYPE_TRANSPORT: 338 mesh_upper_transport_process_segmented_message_done((mesh_transport_pdu_t *) pdu); 339 break; 340 default: 341 break; 342 } 343 } 344 345 static void mesh_upper_transport_validate_segmented_message_digest(void * arg){ 346 mesh_transport_pdu_t * transport_pdu = (mesh_transport_pdu_t*) arg; 347 uint8_t upper_transport_pdu_len = transport_pdu_in_validation->len - transport_pdu_in_validation->transmic_len; 348 uint8_t * upper_transport_pdu_data_in = transport_pdu_in_validation->data; 349 uint8_t * upper_transport_pdu_data_out = transport_pdu->data; 350 btstack_crypto_ccm_decrypt_block(&ccm, upper_transport_pdu_len, upper_transport_pdu_data_in, upper_transport_pdu_data_out, &mesh_upper_transport_validate_segmented_message_ccm, transport_pdu); 351 } 352 353 static void mesh_upper_transport_validate_unsegmented_message_digest(void * arg){ 354 mesh_network_pdu_t * network_pdu = (mesh_network_pdu_t *) arg; 355 uint8_t trans_mic_len = 4; 356 uint8_t lower_transport_pdu_len = network_pdu_in_validation->len - 9; 357 uint8_t * upper_transport_pdu_data_in = &network_pdu_in_validation->data[10]; 358 uint8_t * upper_transport_pdu_data_out = &network_pdu->data[10]; 359 uint8_t upper_transport_pdu_len = lower_transport_pdu_len - 1 - trans_mic_len; 360 btstack_crypto_ccm_decrypt_block(&ccm, upper_transport_pdu_len, upper_transport_pdu_data_in, upper_transport_pdu_data_out, &mesh_upper_transport_validate_unsegmented_message_ccm, network_pdu); 361 } 362 363 static void mesh_upper_transport_validate_unsegmented_message(mesh_network_pdu_t * network_pdu){ 364 365 if (!mesh_transport_key_and_virtual_address_iterator_has_more(&mesh_transport_key_it)){ 366 printf("No valid transport key found\n"); 367 mesh_upper_transport_process_unsegmented_message_done(network_pdu); 368 return; 369 } 370 mesh_transport_key_and_virtual_address_iterator_next(&mesh_transport_key_it); 371 const mesh_transport_key_t * message_key = mesh_transport_key_it.key; 372 373 if (message_key->akf){ 374 transport_unsegmented_setup_application_nonce(application_nonce, network_pdu_in_validation); 375 } else { 376 transport_unsegmented_setup_device_nonce(application_nonce, network_pdu_in_validation); 377 } 378 379 // store application / device key index 380 mesh_print_hex("AppOrDevKey", message_key->key, 16); 381 network_pdu->appkey_index = message_key->appkey_index; 382 383 // unsegmented message have TransMIC of 32 bit 384 uint8_t trans_mic_len = 4; 385 printf("Unsegmented Access message with TransMIC len 4\n"); 386 387 uint8_t lower_transport_pdu_len = network_pdu_in_validation->len - 9; 388 uint8_t * upper_transport_pdu_data = &network_pdu_in_validation->data[10]; 389 uint8_t upper_transport_pdu_len = lower_transport_pdu_len - 1 - trans_mic_len; 390 391 mesh_print_hex("EncAccessPayload", upper_transport_pdu_data, upper_transport_pdu_len); 392 393 // decrypt ccm 394 crypto_active = 1; 395 uint16_t aad_len = 0; 396 if (mesh_network_address_virtual(mesh_network_dst(network_pdu))){ 397 aad_len = 16; 398 } 399 btstack_crypto_ccm_init(&ccm, message_key->key, application_nonce, upper_transport_pdu_len, aad_len, trans_mic_len); 400 if (aad_len){ 401 btstack_crypto_ccm_digest(&ccm, (uint8_t*) mesh_transport_key_it.address->label_uuid, aad_len, &mesh_upper_transport_validate_unsegmented_message_digest, network_pdu); 402 } else { 403 mesh_upper_transport_validate_unsegmented_message_digest(network_pdu); 404 } 405 } 406 407 static void mesh_upper_transport_validate_segmented_message(mesh_transport_pdu_t * transport_pdu){ 408 uint8_t * upper_transport_pdu_data = transport_pdu->data; 409 uint8_t upper_transport_pdu_len = transport_pdu->len - transport_pdu->transmic_len; 410 411 if (!mesh_transport_key_and_virtual_address_iterator_has_more(&mesh_transport_key_it)){ 412 printf("No valid transport key found\n"); 413 mesh_upper_transport_process_segmented_message_done(transport_pdu); 414 return; 415 } 416 mesh_transport_key_and_virtual_address_iterator_next(&mesh_transport_key_it); 417 const mesh_transport_key_t * message_key = mesh_transport_key_it.key; 418 419 if (message_key->akf){ 420 transport_segmented_setup_application_nonce(application_nonce, transport_pdu_in_validation); 421 } else { 422 transport_segmented_setup_device_nonce(application_nonce, transport_pdu_in_validation); 423 } 424 425 // store application / device key index 426 mesh_print_hex("AppOrDevKey", message_key->key, 16); 427 transport_pdu->appkey_index = message_key->appkey_index; 428 429 mesh_print_hex("EncAccessPayload", upper_transport_pdu_data, upper_transport_pdu_len); 430 431 // decrypt ccm 432 crypto_active = 1; 433 uint16_t aad_len = 0; 434 if (mesh_network_address_virtual(mesh_transport_dst(transport_pdu))){ 435 aad_len = 16; 436 } 437 btstack_crypto_ccm_init(&ccm, message_key->key, application_nonce, upper_transport_pdu_len, aad_len, transport_pdu->transmic_len); 438 439 if (aad_len){ 440 btstack_crypto_ccm_digest(&ccm, (uint8_t *) mesh_transport_key_it.address->label_uuid, aad_len, &mesh_upper_transport_validate_segmented_message_digest, transport_pdu); 441 } else { 442 mesh_upper_transport_validate_segmented_message_digest(transport_pdu); 443 } 444 } 445 446 static void mesh_upper_transport_process_unsegmented_access_message(mesh_network_pdu_t *network_pdu){ 447 // copy original pdu 448 network_pdu->len = network_pdu_in_validation->len; 449 memcpy(network_pdu->data, network_pdu_in_validation->data, network_pdu->len); 450 451 // 452 uint8_t * lower_transport_pdu = &network_pdu_in_validation->data[9]; 453 uint8_t lower_transport_pdu_len = network_pdu_in_validation->len - 9; 454 455 mesh_print_hex("Lower Transport network pdu", &network_pdu_in_validation->data[9], lower_transport_pdu_len); 456 457 uint8_t aid = lower_transport_pdu[0] & 0x3f; 458 uint8_t akf = (lower_transport_pdu[0] & 0x40) >> 6; 459 printf("AKF: %u\n", akf); 460 printf("AID: %02x\n", aid); 461 462 mesh_transport_key_and_virtual_address_iterator_init(&mesh_transport_key_it, mesh_network_dst(network_pdu), 463 network_pdu->netkey_index, akf, aid); 464 mesh_upper_transport_validate_unsegmented_message(network_pdu); 465 } 466 467 static void mesh_upper_transport_process_message(mesh_transport_pdu_t * transport_pdu){ 468 // copy original pdu 469 transport_pdu->len = transport_pdu_in_validation->len; 470 memcpy(transport_pdu, transport_pdu_in_validation, sizeof(mesh_transport_pdu_t)); 471 472 // 473 uint8_t * upper_transport_pdu = transport_pdu->data; 474 uint8_t upper_transport_pdu_len = transport_pdu->len - transport_pdu->transmic_len; 475 mesh_print_hex("Upper Transport pdu", upper_transport_pdu, upper_transport_pdu_len); 476 477 uint8_t aid = transport_pdu->akf_aid & 0x3f; 478 uint8_t akf = (transport_pdu->akf_aid & 0x40) >> 6; 479 480 printf("AKF: %u\n", akf); 481 printf("AID: %02x\n", aid); 482 483 mesh_transport_key_and_virtual_address_iterator_init(&mesh_transport_key_it, mesh_transport_dst(transport_pdu), 484 transport_pdu->netkey_index, akf, aid); 485 mesh_upper_transport_validate_segmented_message(transport_pdu); 486 } 487 488 void mesh_upper_transport_message_received(mesh_pdu_t * pdu){ 489 btstack_linked_list_add_tail(&upper_transport_incoming, (btstack_linked_item_t*) pdu); 490 mesh_transport_run(); 491 } 492 493 void mesh_upper_transport_pdu_free(mesh_pdu_t * pdu){ 494 mesh_network_pdu_t * network_pdu; 495 mesh_transport_pdu_t * transport_pdu; 496 switch (pdu->pdu_type) { 497 case MESH_PDU_TYPE_NETWORK: 498 network_pdu = (mesh_network_pdu_t *) pdu; 499 mesh_network_pdu_free(network_pdu); 500 break; 501 case MESH_PDU_TYPE_TRANSPORT: 502 transport_pdu = (mesh_transport_pdu_t *) pdu; 503 mesh_transport_pdu_free(transport_pdu); 504 break; 505 default: 506 break; 507 } 508 } 509 510 void mesh_upper_transport_pdu_handler(mesh_transport_callback_type_t callback_type, mesh_transport_status_t status, mesh_pdu_t * pdu){ 511 switch (callback_type){ 512 case MESH_TRANSPORT_PDU_RECEIVED: 513 mesh_upper_transport_message_received(pdu); 514 break; 515 case MESH_TRANSPORT_PDU_SENT: 516 // notify upper layer (or just free pdu) 517 if (higher_layer_handler){ 518 higher_layer_handler(callback_type, status, pdu); 519 } else { 520 mesh_upper_transport_pdu_free(pdu); 521 } 522 break; 523 default: 524 break; 525 } 526 } 527 static void mesh_upper_transport_send_unsegmented_access_pdu_ccm(void * arg){ 528 crypto_active = 0; 529 530 mesh_network_pdu_t * network_pdu = (mesh_network_pdu_t *) arg; 531 uint8_t * upper_transport_pdu = mesh_network_pdu_data(network_pdu) + 1; 532 uint8_t upper_transport_pdu_len = mesh_network_pdu_len(network_pdu) - 1; 533 mesh_print_hex("EncAccessPayload", upper_transport_pdu, upper_transport_pdu_len); 534 // store TransMIC 535 btstack_crypto_ccm_get_authentication_value(&ccm, &upper_transport_pdu[upper_transport_pdu_len]); 536 mesh_print_hex("TransMIC", &upper_transport_pdu[upper_transport_pdu_len], 4); 537 network_pdu->len += 4; 538 // send network pdu 539 mesh_lower_transport_send_pdu((mesh_pdu_t*) network_pdu); 540 } 541 542 static void mesh_upper_transport_send_segmented_access_pdu_ccm(void * arg){ 543 crypto_active = 0; 544 545 mesh_transport_pdu_t * transport_pdu = (mesh_transport_pdu_t *) arg; 546 mesh_print_hex("EncAccessPayload", transport_pdu->data, transport_pdu->len); 547 // store TransMIC 548 btstack_crypto_ccm_get_authentication_value(&ccm, &transport_pdu->data[transport_pdu->len]); 549 mesh_print_hex("TransMIC", &transport_pdu->data[transport_pdu->len], transport_pdu->transmic_len); 550 transport_pdu->len += transport_pdu->transmic_len; 551 mesh_lower_transport_send_pdu((mesh_pdu_t*) transport_pdu); 552 } 553 554 static uint8_t mesh_upper_transport_setup_unsegmented_control_pdu(mesh_network_pdu_t * network_pdu, uint16_t netkey_index, uint8_t ttl, uint16_t src, uint16_t dest, uint8_t opcode, 555 const uint8_t * control_pdu_data, uint16_t control_pdu_len){ 556 557 printf("[+] Upper transport, setup unsegmented Control PDU (opcode %02x): \n", opcode); 558 printf_hexdump(control_pdu_data, control_pdu_len); 559 560 if (control_pdu_len > 11) return 1; 561 562 const mesh_network_key_t * network_key = mesh_network_key_list_get(netkey_index); 563 if (!network_key) return 1; 564 565 uint8_t transport_pdu_data[12]; 566 transport_pdu_data[0] = opcode; 567 memcpy(&transport_pdu_data[1], control_pdu_data, control_pdu_len); 568 uint16_t transport_pdu_len = control_pdu_len + 1; 569 570 mesh_print_hex("LowerTransportPDU", transport_pdu_data, transport_pdu_len); 571 // setup network_pdu 572 mesh_network_setup_pdu(network_pdu, netkey_index, network_key->nid, 1, ttl, mesh_lower_transport_next_seq(), src, dest, transport_pdu_data, transport_pdu_len); 573 574 return 0; 575 } 576 577 static uint8_t mesh_upper_transport_setup_segmented_control_pdu(mesh_transport_pdu_t * transport_pdu, uint16_t netkey_index, uint8_t ttl, uint16_t src, uint16_t dest, uint8_t opcode, 578 const uint8_t * control_pdu_data, uint16_t control_pdu_len){ 579 580 printf("[+] Upper transport, setup segmented Control PDU (opcode %02x): \n", opcode); 581 printf_hexdump(control_pdu_data, control_pdu_len); 582 583 if (control_pdu_len > 256) return 1; 584 585 const mesh_network_key_t * network_key = mesh_network_key_list_get(netkey_index); 586 if (!network_key) return 1; 587 588 uint32_t seq = mesh_lower_transport_peek_seq(); 589 590 memcpy(transport_pdu->data, control_pdu_data, control_pdu_len); 591 transport_pdu->len = control_pdu_len; 592 transport_pdu->netkey_index = netkey_index; 593 transport_pdu->akf_aid = opcode; 594 transport_pdu->transmic_len = 0; // no TransMIC for control 595 mesh_transport_set_nid_ivi(transport_pdu, network_key->nid); 596 mesh_transport_set_seq(transport_pdu, seq); 597 mesh_transport_set_src(transport_pdu, src); 598 mesh_transport_set_dest(transport_pdu, dest); 599 mesh_transport_set_ctl_ttl(transport_pdu, 0x80 | ttl); 600 601 return 0; 602 } 603 604 uint8_t mesh_upper_transport_setup_control_pdu(mesh_pdu_t * pdu, uint16_t netkey_index, 605 uint8_t ttl, uint16_t src, uint16_t dest, uint8_t opcode, const uint8_t * control_pdu_data, uint16_t control_pdu_len){ 606 switch (pdu->pdu_type){ 607 case MESH_PDU_TYPE_NETWORK: 608 return mesh_upper_transport_setup_unsegmented_control_pdu((mesh_network_pdu_t *) pdu, netkey_index, ttl, src, dest, opcode, control_pdu_data, control_pdu_len); 609 case MESH_PDU_TYPE_TRANSPORT: 610 return mesh_upper_transport_setup_segmented_control_pdu((mesh_transport_pdu_t *) pdu, netkey_index, ttl, src, dest, opcode, control_pdu_data, control_pdu_len); 611 default: 612 return 1; 613 } 614 } 615 616 static uint8_t mesh_upper_transport_setup_unsegmented_access_pdu_header(mesh_network_pdu_t * network_pdu, uint16_t netkey_index, 617 uint16_t appkey_index, uint8_t ttl, uint16_t src, uint16_t dest){ 618 619 // get app or device key 620 const mesh_transport_key_t * appkey; 621 appkey = mesh_transport_key_get(appkey_index); 622 if (appkey == NULL){ 623 printf("appkey_index %x unknown\n", appkey_index); 624 return 1; 625 } 626 uint8_t akf_aid = (appkey->akf << 6) | appkey->aid; 627 628 // lookup network by netkey_index 629 const mesh_network_key_t * network_key = mesh_network_key_list_get(netkey_index); 630 if (!network_key) return 1; 631 632 network_pdu->data[9] = akf_aid; 633 // setup network_pdu 634 mesh_network_setup_pdu_header(network_pdu, netkey_index, network_key->nid, 0, ttl, mesh_lower_transport_next_seq(), src, dest); 635 network_pdu->appkey_index = appkey_index; 636 return 0; 637 } 638 639 static uint8_t mesh_upper_transport_setup_unsegmented_access_pdu(mesh_network_pdu_t * network_pdu, uint16_t netkey_index, uint16_t appkey_index, uint8_t ttl, uint16_t src, uint16_t dest, 640 const uint8_t * access_pdu_data, uint8_t access_pdu_len){ 641 642 int status = mesh_upper_transport_setup_unsegmented_access_pdu_header(network_pdu, netkey_index, appkey_index, ttl, src, dest); 643 if (status) return status; 644 645 printf("[+] Upper transport, setup unsegmented Access PDU - seq %06x\n", mesh_network_seq(network_pdu)); 646 mesh_print_hex("Access Payload", access_pdu_data, access_pdu_len); 647 648 // store in transport pdu 649 memcpy(&network_pdu->data[10], access_pdu_data, access_pdu_len); 650 network_pdu->len = 10 + access_pdu_len; 651 return 0; 652 } 653 654 static uint8_t mesh_upper_transport_setup_segmented_access_pdu_header(mesh_transport_pdu_t * transport_pdu, uint16_t netkey_index, uint16_t appkey_index, uint8_t ttl, uint16_t src, uint16_t dest, 655 uint8_t szmic){ 656 uint32_t seq = mesh_lower_transport_peek_seq(); 657 658 printf("[+] Upper transport, setup segmented Access PDU - seq %06x, szmic %u, iv_index %08x\n", seq, szmic, 659 mesh_get_iv_index_for_tx()); 660 mesh_print_hex("Access Payload", transport_pdu->data, transport_pdu->len); 661 662 // get app or device key 663 const mesh_transport_key_t *appkey; 664 appkey = mesh_transport_key_get(appkey_index); 665 if (appkey == NULL) { 666 printf("appkey_index %x unknown\n", appkey_index); 667 return 1; 668 } 669 uint8_t akf_aid = (appkey->akf << 6) | appkey->aid; 670 671 // lookup network by netkey_index 672 const mesh_network_key_t *network_key = mesh_network_key_list_get(netkey_index); 673 if (!network_key) return 1; 674 675 const uint8_t trans_mic_len = szmic ? 8 : 4; 676 677 // store in transport pdu 678 transport_pdu->transmic_len = trans_mic_len; 679 transport_pdu->netkey_index = netkey_index; 680 transport_pdu->appkey_index = appkey_index; 681 transport_pdu->akf_aid = akf_aid; 682 mesh_transport_set_nid_ivi(transport_pdu, network_key->nid | ((mesh_get_iv_index_for_tx() & 1) << 7)); 683 mesh_transport_set_seq(transport_pdu, seq); 684 mesh_transport_set_src(transport_pdu, src); 685 mesh_transport_set_dest(transport_pdu, dest); 686 mesh_transport_set_ctl_ttl(transport_pdu, ttl); 687 return 0; 688 } 689 690 691 static uint8_t mesh_upper_transport_setup_segmented_access_pdu(mesh_transport_pdu_t * transport_pdu, uint16_t netkey_index, uint16_t appkey_index, uint8_t ttl, uint16_t src, uint16_t dest, 692 uint8_t szmic, const uint8_t * access_pdu_data, uint8_t access_pdu_len){ 693 int status = mesh_upper_transport_setup_segmented_access_pdu_header(transport_pdu, netkey_index, appkey_index, ttl, src, dest, szmic); 694 if (status) return status; 695 696 // store in transport pdu 697 memcpy(transport_pdu->data, access_pdu_data, access_pdu_len); 698 transport_pdu->len = access_pdu_len; 699 return 0; 700 } 701 uint8_t mesh_upper_transport_setup_access_pdu_header(mesh_pdu_t * pdu, uint16_t netkey_index, uint16_t appkey_index, 702 uint8_t ttl, uint16_t src, uint16_t dest, uint8_t szmic){ 703 switch (pdu->pdu_type){ 704 case MESH_PDU_TYPE_NETWORK: 705 return mesh_upper_transport_setup_unsegmented_access_pdu_header((mesh_network_pdu_t *) pdu, netkey_index, appkey_index, ttl, src, dest); 706 case MESH_PDU_TYPE_TRANSPORT: 707 return mesh_upper_transport_setup_segmented_access_pdu_header((mesh_transport_pdu_t *) pdu, netkey_index, appkey_index, ttl, src, dest, szmic); 708 default: 709 return 1; 710 } 711 } 712 713 uint8_t mesh_upper_transport_setup_access_pdu(mesh_pdu_t * pdu, uint16_t netkey_index, uint16_t appkey_index, 714 uint8_t ttl, uint16_t src, uint16_t dest, uint8_t szmic, 715 const uint8_t * access_pdu_data, uint8_t access_pdu_len){ 716 switch (pdu->pdu_type){ 717 case MESH_PDU_TYPE_NETWORK: 718 return mesh_upper_transport_setup_unsegmented_access_pdu((mesh_network_pdu_t *) pdu, netkey_index, appkey_index, ttl, src, dest, access_pdu_data, access_pdu_len); 719 case MESH_PDU_TYPE_TRANSPORT: 720 return mesh_upper_transport_setup_segmented_access_pdu((mesh_transport_pdu_t *) pdu, netkey_index, appkey_index, ttl, src, dest, szmic, access_pdu_data, access_pdu_len); 721 default: 722 return 1; 723 } 724 } 725 726 void mesh_upper_transport_send_control_pdu(mesh_pdu_t * pdu){ 727 mesh_lower_transport_send_pdu((mesh_pdu_t*) pdu); 728 } 729 730 static void mesh_upper_transport_send_unsegmented_access_pdu_digest(void * arg){ 731 mesh_network_pdu_t * network_pdu = (mesh_network_pdu_t *) arg; 732 uint8_t * access_pdu_data = mesh_network_pdu_data(network_pdu) + 1; 733 uint16_t access_pdu_len = mesh_network_pdu_len(network_pdu) - 1; 734 btstack_crypto_ccm_encrypt_block(&ccm, access_pdu_len, access_pdu_data, access_pdu_data, &mesh_upper_transport_send_unsegmented_access_pdu_ccm, network_pdu); 735 } 736 737 static mesh_transport_key_t * mesh_upper_transport_get_outgoing_appkey(uint16_t netkey_index, uint16_t appkey_index){ 738 // Device Key is fixed 739 if (appkey_index == MESH_DEVICE_KEY_INDEX) { 740 return mesh_transport_key_get(appkey_index); 741 } 742 743 // Get key refresh state from subnet 744 mesh_subnet_t * subnet = mesh_subnet_get_by_netkey_index(netkey_index); 745 if (subnet == NULL) return NULL; 746 747 // identify old and new app keys for given appkey_index 748 mesh_transport_key_t * old_key = NULL; 749 mesh_transport_key_t * new_key = NULL; 750 mesh_transport_key_iterator_t it; 751 mesh_transport_key_iterator_init(&it, netkey_index); 752 while (mesh_transport_key_iterator_has_more(&it)){ 753 mesh_transport_key_t * transport_key = mesh_transport_key_iterator_get_next(&it); 754 if (transport_key->appkey_index != appkey_index) continue; 755 if (transport_key->old_key == 0) { 756 new_key = transport_key; 757 } else { 758 old_key = transport_key; 759 } 760 } 761 762 // if no key is marked as old, just use the current one 763 if (old_key == NULL) return new_key; 764 765 // use new key if it exists in phase two 766 if ((subnet->key_refresh == MESH_KEY_REFRESH_SECOND_PHASE) && (new_key != NULL)){ 767 return new_key; 768 } else { 769 return old_key; 770 } 771 } 772 773 static void mesh_upper_transport_send_unsegmented_access_pdu(mesh_network_pdu_t * network_pdu){ 774 775 // if dst is virtual address, lookup label uuid and hash 776 uint16_t aad_len = 0; 777 mesh_virtual_address_t * virtual_address = NULL; 778 uint16_t dst = mesh_network_dst(network_pdu); 779 if (mesh_network_address_virtual(dst)){ 780 virtual_address = mesh_virtual_address_for_pseudo_dst(dst); 781 if (!virtual_address){ 782 printf("No virtual address register for pseudo dst %4x\n", dst); 783 btstack_memory_mesh_network_pdu_free(network_pdu); 784 return; 785 } 786 aad_len = 16; 787 big_endian_store_16(network_pdu->data, 7, virtual_address->hash); 788 } 789 790 // setup nonce 791 uint16_t appkey_index = network_pdu->appkey_index; 792 if (appkey_index == MESH_DEVICE_KEY_INDEX){ 793 transport_unsegmented_setup_device_nonce(application_nonce, network_pdu); 794 } else { 795 transport_unsegmented_setup_application_nonce(application_nonce, network_pdu); 796 } 797 798 // get app or device key 799 const mesh_transport_key_t * appkey = mesh_upper_transport_get_outgoing_appkey(network_pdu->netkey_index, appkey_index); 800 mesh_print_hex("AppOrDevKey", appkey->key, 16); 801 802 // encrypt ccm 803 uint8_t trans_mic_len = 4; 804 uint16_t access_pdu_len = mesh_network_pdu_len(network_pdu) - 1; 805 crypto_active = 1; 806 807 btstack_crypto_ccm_init(&ccm, appkey->key, application_nonce, access_pdu_len, aad_len, trans_mic_len); 808 if (virtual_address){ 809 mesh_print_hex("LabelUUID", virtual_address->label_uuid, 16); 810 btstack_crypto_ccm_digest(&ccm, virtual_address->label_uuid, 16, &mesh_upper_transport_send_unsegmented_access_pdu_digest, network_pdu); 811 } else { 812 mesh_upper_transport_send_unsegmented_access_pdu_digest(network_pdu); 813 } 814 } 815 816 static void mesh_upper_transport_send_segmented_access_pdu_digest(void *arg){ 817 mesh_transport_pdu_t * transport_pdu = (mesh_transport_pdu_t *) arg; 818 uint16_t access_pdu_len = transport_pdu->len; 819 uint8_t * access_pdu_data = transport_pdu->data; 820 btstack_crypto_ccm_encrypt_block(&ccm, access_pdu_len,access_pdu_data, access_pdu_data, &mesh_upper_transport_send_segmented_access_pdu_ccm, transport_pdu); 821 } 822 823 static void mesh_upper_transport_send_segmented_access_pdu(mesh_transport_pdu_t * transport_pdu){ 824 825 // if dst is virtual address, lookup label uuid and hash 826 uint16_t aad_len = 0; 827 mesh_virtual_address_t * virtual_address = NULL; 828 uint16_t dst = mesh_transport_dst(transport_pdu); 829 if (mesh_network_address_virtual(dst)){ 830 virtual_address = mesh_virtual_address_for_pseudo_dst(dst); 831 if (!virtual_address){ 832 printf("No virtual address register for pseudo dst %4x\n", dst); 833 btstack_memory_mesh_transport_pdu_free(transport_pdu); 834 return; 835 } 836 // printf("Using hash %4x with LabelUUID: ", virtual_address->hash); 837 // printf_hexdump(virtual_address->label_uuid, 16); 838 aad_len = 16; 839 big_endian_store_16(transport_pdu->network_header, 7, virtual_address->hash); 840 } 841 842 // setup nonce - uses dst, so after pseudo address translation 843 uint16_t appkey_index = transport_pdu->appkey_index; 844 if (appkey_index == MESH_DEVICE_KEY_INDEX){ 845 transport_segmented_setup_device_nonce(application_nonce, transport_pdu); 846 } else { 847 transport_segmented_setup_application_nonce(application_nonce, transport_pdu); 848 } 849 850 // get app or device key 851 const mesh_transport_key_t * appkey = mesh_upper_transport_get_outgoing_appkey(transport_pdu->netkey_index, appkey_index); 852 mesh_print_hex("AppOrDevKey", appkey->key, 16); 853 854 // encrypt ccm 855 uint8_t transmic_len = transport_pdu->transmic_len; 856 uint16_t access_pdu_len = transport_pdu->len; 857 crypto_active = 1; 858 btstack_crypto_ccm_init(&ccm, appkey->key, application_nonce, access_pdu_len, aad_len, transmic_len); 859 if (virtual_address){ 860 mesh_print_hex("LabelUUID", virtual_address->label_uuid, 16); 861 btstack_crypto_ccm_digest(&ccm, virtual_address->label_uuid, 16, &mesh_upper_transport_send_segmented_access_pdu_digest, transport_pdu); 862 } else { 863 mesh_upper_transport_send_segmented_access_pdu_digest(transport_pdu); 864 } 865 } 866 867 void mesh_upper_transport_send_access_pdu(mesh_pdu_t * pdu){ 868 switch (pdu->pdu_type){ 869 case MESH_PDU_TYPE_NETWORK: 870 mesh_upper_transport_send_unsegmented_access_pdu((mesh_network_pdu_t *) pdu); 871 break; 872 case MESH_PDU_TYPE_TRANSPORT: 873 mesh_upper_transport_send_segmented_access_pdu((mesh_transport_pdu_t *) pdu); 874 break; 875 default: 876 break; 877 } 878 } 879 880 void mesh_upper_transport_set_primary_element_address(uint16_t unicast_address){ 881 primary_element_address = unicast_address; 882 } 883 884 void mesh_upper_transport_register_access_message_handler(void (*callback)(mesh_pdu_t *pdu)){ 885 mesh_access_message_handler = callback; 886 } 887 888 void mesh_upper_transport_register_control_message_handler(void (*callback)(mesh_pdu_t *pdu)){ 889 mesh_control_message_handler = callback; 890 } 891 892 void mesh_upper_transport_set_higher_layer_handler(void (*pdu_handler)( mesh_transport_callback_type_t callback_type, mesh_transport_status_t status, mesh_pdu_t * pdu)){ 893 higher_layer_handler = pdu_handler; 894 } 895 896 void mesh_upper_transport_init(){ 897 mesh_lower_transport_init(); 898 mesh_lower_transport_set_higher_layer_handler(&mesh_upper_transport_pdu_handler); 899 } 900 901 static void mesh_transport_run(void){ 902 while(!btstack_linked_list_empty(&upper_transport_incoming)){ 903 904 if (crypto_active) return; 905 906 // peek at next message 907 mesh_pdu_t * pdu = (mesh_pdu_t *) btstack_linked_list_get_first_item(&upper_transport_incoming); 908 mesh_transport_pdu_t * transport_pdu; 909 mesh_network_pdu_t * network_pdu; 910 switch (pdu->pdu_type){ 911 case MESH_PDU_TYPE_NETWORK: 912 network_pdu = (mesh_network_pdu_t *) pdu; 913 // control? 914 if (mesh_network_control(network_pdu)) { 915 (void) btstack_linked_list_pop(&upper_transport_incoming); 916 mesh_upper_unsegmented_control_message_received(network_pdu); 917 } else { 918 mesh_network_pdu_t * decode_pdu = mesh_network_pdu_get(); 919 if (!decode_pdu) return; 920 // get encoded network pdu and start processing 921 network_pdu_in_validation = network_pdu; 922 (void) btstack_linked_list_pop(&upper_transport_incoming); 923 mesh_upper_transport_process_unsegmented_access_message(decode_pdu); 924 } 925 break; 926 case MESH_PDU_TYPE_TRANSPORT: 927 transport_pdu = (mesh_transport_pdu_t *) pdu; 928 uint8_t ctl = mesh_transport_ctl(transport_pdu); 929 if (ctl){ 930 printf("Ignoring Segmented Control Message\n"); 931 (void) btstack_linked_list_pop(&upper_transport_incoming); 932 mesh_lower_transport_message_processed_by_higher_layer((mesh_pdu_t *) transport_pdu); 933 } else { 934 mesh_transport_pdu_t * decode_pdu = mesh_transport_pdu_get(); 935 if (!decode_pdu) return; 936 // get encoded transport pdu and start processing 937 transport_pdu_in_validation = transport_pdu; 938 (void) btstack_linked_list_pop(&upper_transport_incoming); 939 mesh_upper_transport_process_message(decode_pdu); 940 } 941 break; 942 default: 943 break; 944 } 945 } 946 } 947 948 // buffer pool 949 mesh_transport_pdu_t * mesh_transport_pdu_get(void){ 950 mesh_transport_pdu_t * transport_pdu = btstack_memory_mesh_transport_pdu_get(); 951 if (transport_pdu) { 952 memset(transport_pdu, 0, sizeof(mesh_transport_pdu_t)); 953 transport_pdu->pdu_header.pdu_type = MESH_PDU_TYPE_TRANSPORT; 954 } 955 return transport_pdu; 956 } 957 958 void mesh_transport_pdu_free(mesh_transport_pdu_t * transport_pdu){ 959 btstack_memory_mesh_transport_pdu_free(transport_pdu); 960 } 961