xref: /btstack/src/mesh/mesh_network.c (revision d4e23df00f1e6e1d0c01ce9b858f515a414fc015)
1 /*
2  * Copyright (C) 2018 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_network.c"
39 
40 #include <stdio.h>
41 #include <stdlib.h>
42 #include <string.h>
43 
44 #include "btstack_debug.h"
45 #include "btstack_event.h"
46 #include "btstack_memory.h"
47 #include "btstack_util.h"
48 
49 #include "mesh/beacon.h"
50 #include "mesh/mesh_foundation.h"
51 #include "mesh/mesh_iv_index_seq_number.h"
52 #include "mesh/mesh_keys.h"
53 #include "mesh/mesh_node.h"
54 #include "mesh/provisioning.h"
55 #include "mesh/provisioning_device.h"
56 
57 #ifdef ENABLE_MESH_ADV_BEARER
58 #include "mesh/adv_bearer.h"
59 #endif
60 
61 #ifdef ENABLE_MESH_GATT_BEARER
62 #include "mesh/gatt_bearer.h"
63 #endif
64 
65 // configuration
66 #define MESH_NETWORK_CACHE_SIZE 2
67 
68 // debug config
69 // #define LOG_NETWORK
70 
71 static void mesh_network_dump_network_pdus(const char * name, btstack_linked_list_t * list);
72 
73 // structs
74 
75 // globals
76 
77 static void (*mesh_network_higher_layer_handler)(mesh_network_callback_type_t callback_type, mesh_network_pdu_t * network_pdu);
78 static void (*mesh_network_proxy_message_handler)(mesh_network_callback_type_t callback_type, mesh_network_pdu_t * network_pdu);
79 
80 #ifdef ENABLE_MESH_GATT_BEARER
81 static hci_con_handle_t gatt_bearer_con_handle;
82 #endif
83 
84 // shared send/receive crypto
85 static int mesh_crypto_active;
86 
87 // crypto requests
88 static union {
89     btstack_crypto_ccm_t         ccm;
90     btstack_crypto_aes128_t      aes128;
91 } mesh_network_crypto_request;
92 
93 static const mesh_network_key_t *  current_network_key;
94 
95 // PECB calculation
96 static uint8_t encryption_block[16];
97 static uint8_t obfuscation_block[16];
98 
99 // Subnets
100 static btstack_linked_list_t subnets;
101 
102 // Network Nonce
103 static uint8_t network_nonce[13];
104 
105 // INCOMING //
106 
107 // unprocessed network pdu - added by mesh_network_pdus_received_message
108 static btstack_linked_list_t        network_pdus_received;
109 
110 // in validation
111 static mesh_network_pdu_t *         incoming_pdu_raw;
112 static mesh_network_pdu_t *         incoming_pdu_decoded;
113 static mesh_network_key_iterator_t  validation_network_key_it;
114 
115 // OUTGOING //
116 
117 // Network PDUs queued by mesh_network_send
118 static btstack_linked_list_t network_pdus_queued;
119 
120 // Network PDU about to get send via all bearers when encrypted
121 static mesh_network_pdu_t * outgoing_pdu;
122 
123 // Network PDUs ready to send via GATT Bearer
124 static btstack_linked_list_t network_pdus_outgoing_gatt;
125 
126 #ifdef ENABLE_MESH_GATT_BEARER
127 static mesh_network_pdu_t * gatt_bearer_network_pdu;
128 #endif
129 
130 // Network PDUs ready to send via ADV Bearer
131 static btstack_linked_list_t network_pdus_outgoing_adv;
132 
133 #ifdef ENABLE_MESH_ADV_BEARER
134 static mesh_network_pdu_t * adv_bearer_network_pdu;
135 #endif
136 
137 
138 // mesh network cache - we use 32-bit 'hashes'
139 static uint32_t mesh_network_cache[MESH_NETWORK_CACHE_SIZE];
140 static int      mesh_network_cache_index;
141 
142 // prototypes
143 
144 static void mesh_network_run(void);
145 static void process_network_pdu_validate(void);
146 
147 // network caching
148 static uint32_t mesh_network_cache_hash(mesh_network_pdu_t * network_pdu){
149     // - The SEQ field is a 24-bit integer that when combined with the IV Index,
150     // shall be a unique value for each new Network PDU originated by this node (=> SRC)
151     // - IV updates only rarely
152     // => 16 bit SRC, 1 bit IVI, 15 bit SEQ
153     uint8_t  ivi = network_pdu->data[0] >> 7;
154     uint16_t seq = big_endian_read_16(network_pdu->data, 3);
155     uint16_t src = big_endian_read_16(network_pdu->data, 5);
156     return (src << 16) | (ivi << 15) | (seq & 0x7fff);
157 }
158 
159 static int mesh_network_cache_find(uint32_t hash){
160     int i;
161     for (i = 0; i < MESH_NETWORK_CACHE_SIZE; i++) {
162         if (mesh_network_cache[i] == hash) {
163             return 1;
164         }
165     }
166     return 0;
167 }
168 
169 static void mesh_network_cache_add(uint32_t hash){
170     mesh_network_cache[mesh_network_cache_index++] = hash;
171     if (mesh_network_cache_index >= MESH_NETWORK_CACHE_SIZE){
172         mesh_network_cache_index = 0;
173     }
174 }
175 
176 // common helper
177 int mesh_network_address_unicast(uint16_t addr){
178     return addr != MESH_ADDRESS_UNSASSIGNED && (addr < 0x8000);
179 }
180 
181 int mesh_network_address_virtual(uint16_t addr){
182     return (addr & 0xC000) == 0x8000;   // 0b10xx xxxx xxxx xxxx
183 }
184 
185 int mesh_network_address_group(uint16_t addr){
186     return (addr & 0xC000) == 0xC000;   // 0b11xx xxxx xxxx xxxx
187 }
188 
189 int mesh_network_address_all_proxies(uint16_t addr){
190     return addr == MESH_ADDRESS_ALL_PROXIES;
191 }
192 
193 int mesh_network_address_all_nodes(uint16_t addr){
194     return addr == MESH_ADDRESS_ALL_NODES;
195 }
196 
197 int mesh_network_address_all_friends(uint16_t addr){
198     return addr == MESH_ADDRESS_ALL_FRIENDS;
199 }
200 
201 int mesh_network_address_all_relays(uint16_t addr){
202     return addr == MESH_ADDRESS_ALL_RELAYS;
203 }
204 
205 int mesh_network_addresses_valid(uint8_t ctl, uint16_t src, uint16_t dst){
206     // printf("CTL: %u\n", ctl);
207     // printf("SRC: %04x\n", src);
208     // printf("DST: %04x\n", dst);
209     if (src == 0){
210         // printf("SRC Unassigned Addr -> ignore\n");
211         return 0;
212     }
213     if ((src & 0xC000) == 0x8000){
214         // printf("SRC Virtual Addr -> ignore\n");
215         return 0;
216     }
217     if ((src & 0xC000) == 0xC000){
218         // printf("SRC Group Addr -> ignore\n");
219         return 0;
220     }
221     if (dst == 0){
222         // printf("DST Unassigned Addr -> ignore\n");
223         return 0;
224     }
225     if ( ((dst & 0xC000) == 0x8000) && (ctl == 1)){
226         // printf("DST Virtual Addr in CONTROL -> ignore\n");
227         return 0;
228     }
229     if ( (0xFF00 <= dst) && (dst <= 0xfffb) && (ctl == 0) ){
230         // printf("DST RFU Group Addr in MESSAGE -> ignore\n");
231         return 0;
232     }
233     // printf("SRC + DST Addr valid\n");
234     return 1;
235 }
236 
237 static void mesh_network_create_nonce(uint8_t * nonce, const mesh_network_pdu_t * pdu, uint32_t iv_index){
238     unsigned int pos = 0;
239     nonce[pos++] = 0x0;      // Network Nonce
240     memcpy(&nonce[pos], &pdu->data[1], 6);
241     pos += 6;
242     big_endian_store_16(nonce, pos, 0);
243     pos += 2;
244     big_endian_store_32(nonce, pos, iv_index);
245 }
246 
247 static void mesh_proxy_create_nonce(uint8_t * nonce, const mesh_network_pdu_t * pdu, uint32_t iv_index){
248     unsigned int pos = 0;
249     nonce[pos++] = 0x3;      // Proxy Nonce
250     nonce[pos++] = 0;
251     memcpy(&nonce[pos], &pdu->data[2], 5);
252     pos += 5;
253     big_endian_store_16(nonce, pos, 0);
254     pos += 2;
255     big_endian_store_32(nonce, pos, iv_index);
256 }
257 
258 // NID/IVI | obfuscated (CTL/TTL, SEQ (24), SRC (16) ), encrypted ( DST(16), TransportPDU), MIC(32 or 64)
259 
260 static void mesh_network_send_complete(mesh_network_pdu_t * network_pdu){
261     if (network_pdu->flags & MESH_NETWORK_PDU_FLAGS_RELAY){
262 #ifdef LOG_NETWORK
263         printf("TX-F-NetworkPDU (%p): relay -> free packet\n", network_pdu);
264 #endif
265         mesh_network_pdu_free(network_pdu);
266     } else {
267 #ifdef LOG_NETWORK
268         printf("TX-F-NetworkPDU (%p): notify lower transport\n", network_pdu);
269 #endif
270         // notify higher layer
271         (*mesh_network_higher_layer_handler)(MESH_NETWORK_PDU_SENT, network_pdu);
272     }
273 }
274 
275 static void mesh_network_send_d(mesh_network_pdu_t * network_pdu){
276 
277 #ifdef LOG_NETWORK
278     printf("TX-D-NetworkPDU (%p): ", network_pdu);
279     printf_hexdump(network_pdu->data, network_pdu->len);
280 #endif
281 
282     // add to queue
283     btstack_linked_list_add_tail(&network_pdus_outgoing_gatt, (btstack_linked_item_t *) network_pdu);
284 
285     // go
286     mesh_network_run();
287 }
288 
289 // new
290 static void mesh_network_send_c(void *arg){
291     UNUSED(arg);
292 
293     // obfuscate
294     unsigned int i;
295     for (i=0;i<6;i++){
296         outgoing_pdu->data[1+i] ^= obfuscation_block[i];
297     }
298 
299 #ifdef LOG_NETWORK
300     printf("TX-C-NetworkPDU (%p): ", outgoing_pdu);
301     printf_hexdump(outgoing_pdu->data, outgoing_pdu->len);
302 #endif
303 
304     // crypto done
305     mesh_crypto_active = 0;
306 
307     // done
308     mesh_network_pdu_t * network_pdu = outgoing_pdu;
309     outgoing_pdu = NULL;
310     (network_pdu->callback)(network_pdu);
311 }
312 
313 static void mesh_network_send_b(void *arg){
314     UNUSED(arg);
315 
316     uint32_t iv_index = mesh_get_iv_index_for_tx();
317 
318     // store NetMIC
319     uint8_t net_mic[8];
320     btstack_crypto_ccm_get_authentication_value(&mesh_network_crypto_request.ccm, net_mic);
321 
322     // store MIC
323     uint8_t net_mic_len = outgoing_pdu->data[1] & 0x80 ? 8 : 4;
324     memcpy(&outgoing_pdu->data[outgoing_pdu->len], net_mic, net_mic_len);
325     outgoing_pdu->len += net_mic_len;
326 
327     btstack_assert(outgoing_pdu->len <= 29);
328 
329 #ifdef LOG_NETWORK
330     printf("TX-B-NetworkPDU (%p): ", outgoing_pdu);
331     printf_hexdump(outgoing_pdu->data, outgoing_pdu->len);
332 #endif
333 
334     // calc PECB
335     memset(encryption_block, 0, 5);
336     big_endian_store_32(encryption_block, 5, iv_index);
337     memcpy(&encryption_block[9], &outgoing_pdu->data[7], 7);
338     btstack_crypto_aes128_encrypt(&mesh_network_crypto_request.aes128, current_network_key->privacy_key, encryption_block, obfuscation_block, &mesh_network_send_c, NULL);
339 }
340 
341 static void mesh_network_send_a(void){
342 
343     mesh_crypto_active = 1;
344 
345     uint32_t iv_index = mesh_get_iv_index_for_tx();
346 
347     // lookup subnet by netkey_index
348     mesh_subnet_t * subnet = mesh_subnet_get_by_netkey_index(outgoing_pdu->netkey_index);
349     if (!subnet) {
350         mesh_crypto_active = 0;
351         mesh_network_pdu_t * network_pdu = outgoing_pdu;
352         outgoing_pdu = NULL;
353         // notify upper layer
354         mesh_network_send_complete(network_pdu);
355         // run again
356         mesh_network_run();
357         return;
358     }
359 
360     // get network key to use for sending
361     current_network_key = mesh_subnet_get_outgoing_network_key(subnet);
362 
363 #ifdef LOG_NETWORK
364     printf("TX-A-NetworkPDU (%p): ", outgoing_pdu);
365     printf_hexdump(outgoing_pdu->data, outgoing_pdu->len);
366 #endif
367 
368     // get network nonce
369     if (outgoing_pdu->flags & MESH_NETWORK_PDU_FLAGS_PROXY_CONFIGURATION){
370         mesh_proxy_create_nonce(network_nonce, outgoing_pdu, iv_index);
371 #ifdef LOG_NETWORK
372         printf("TX-ProxyNonce:  ");
373         printf_hexdump(network_nonce, 13);
374 #endif
375     } else {
376         mesh_network_create_nonce(network_nonce, outgoing_pdu, iv_index);
377 #ifdef LOG_NETWORK
378         printf("TX-NetworkNonce:  ");
379         printf_hexdump(network_nonce, 13);
380 #endif
381     }
382 
383 #ifdef LOG_NETWORK
384    printf("TX-EncryptionKey: ");
385     printf_hexdump(current_network_key->encryption_key, 16);
386 #endif
387 
388     // start ccm
389     uint8_t cypher_len  = outgoing_pdu->len - 7;
390     uint8_t net_mic_len = outgoing_pdu->data[1] & 0x80 ? 8 : 4;
391     btstack_crypto_ccm_init(&mesh_network_crypto_request.ccm, current_network_key->encryption_key, network_nonce, cypher_len, 0, net_mic_len);
392     btstack_crypto_ccm_encrypt_block(&mesh_network_crypto_request.ccm, cypher_len, &outgoing_pdu->data[7], &outgoing_pdu->data[7], &mesh_network_send_b, NULL);
393 }
394 
395 #if defined(ENABLE_MESH_RELAY) || defined (ENABLE_MESH_PROXY_SERVER)
396 static void mesh_network_relay_message(mesh_network_pdu_t * network_pdu){
397 
398     uint8_t ctl_ttl     = network_pdu->data[1];
399     uint8_t ctl         = ctl_ttl & 0x80;
400     uint8_t ttl         = ctl_ttl & 0x7f;
401 
402 #ifdef LOG_NETWORK
403     printf("TX-Relay-NetworkPDU (%p): ", network_pdu);
404     printf_hexdump(network_pdu->data, network_pdu->len);
405     printf("^^ into network_pdus_queued\n");
406 #endif
407 
408     // prepare pdu for resending
409     network_pdu->data[1] = (ctl << 7) | (ttl - 1);
410     network_pdu->flags |= MESH_NETWORK_PDU_FLAGS_RELAY;
411 
412     // queue up
413     network_pdu->callback = &mesh_network_send_d;
414     btstack_linked_list_add_tail(&network_pdus_queued, (btstack_linked_item_t *) network_pdu);
415 }
416 #endif
417 
418 void mesh_network_message_processed_by_higher_layer(mesh_network_pdu_t * network_pdu){
419 
420 #if defined(ENABLE_MESH_RELAY) || defined (ENABLE_MESH_PROXY_SERVER)
421 
422     // check if address does not matches elements on our node and TTL >= 2
423     uint16_t src     = mesh_network_src(network_pdu);
424     uint8_t  ttl     = mesh_network_ttl(network_pdu);
425 
426     uint16_t mesh_network_primary_address = mesh_node_get_primary_element_address();
427 
428     if (((src < mesh_network_primary_address) || (src > (mesh_network_primary_address + mesh_node_element_count()))) && (ttl >= 2)){
429 
430         if ((network_pdu->flags & MESH_NETWORK_PDU_FLAGS_GATT_BEARER) == 0){
431 
432             // message received via ADV bearer are relayed:
433 
434 #ifdef ENABLE_MESH_RELAY
435             if (mesh_foundation_relay_get() != 0){
436                 // - to ADV bearer, if Relay supported and enabled
437                 mesh_network_relay_message(network_pdu);
438                 mesh_network_run();
439                 return;
440             }
441 #endif
442 
443 #ifdef ENABLE_MESH_PROXY_SERVER
444             if (mesh_foundation_gatt_proxy_get() != 0){
445                 // - to GATT bearer, if Proxy supported and enabled
446                 mesh_network_relay_message(network_pdu);
447                 mesh_network_run();
448                 return;
449             }
450 #endif
451 
452         } else {
453 
454             // messages received via GATT bearer are relayed:
455 
456 #ifdef ENABLE_MESH_PROXY_SERVER
457             if (mesh_foundation_gatt_proxy_get() != 0){
458                 // - to ADV bearer, if Proxy supported and enabled
459                 mesh_network_relay_message(network_pdu);
460                 mesh_network_run();
461                 return;
462             }
463 #endif
464 
465         }
466     }
467 #endif
468 
469     // otherwise, we're done
470     btstack_memory_mesh_network_pdu_free(network_pdu);
471 }
472 
473 static void process_network_pdu_done(void){
474     btstack_memory_mesh_network_pdu_free(incoming_pdu_raw);
475     incoming_pdu_raw = NULL;
476     mesh_crypto_active = 0;
477 
478     mesh_network_run();
479 }
480 
481 static void process_network_pdu_validate_d(void * arg){
482     UNUSED(arg);
483     // mesh_network_pdu_t * network_pdu = (mesh_network_pdu_t *) arg;
484 
485     uint8_t ctl_ttl     = incoming_pdu_decoded->data[1];
486     uint8_t ctl         = ctl_ttl >> 7;
487     uint8_t net_mic_len = (ctl_ttl & 0x80) ? 8 : 4;
488 
489     // store NetMIC
490     uint8_t net_mic[8];
491     btstack_crypto_ccm_get_authentication_value(&mesh_network_crypto_request.ccm, net_mic);
492 #ifdef LOG_NETWORK
493     printf("RX-NetMIC (%p): ", incoming_pdu_decoded);
494     printf_hexdump(net_mic, net_mic_len);
495 #endif
496     // store in decoded pdu
497     memcpy(&incoming_pdu_decoded->data[incoming_pdu_decoded->len-net_mic_len], net_mic, net_mic_len);
498 
499 #ifdef LOG_NETWORK
500     uint8_t cypher_len  = incoming_pdu_decoded->len - 9 - net_mic_len;
501     printf("RX-Decrypted DST/TransportPDU (%p): ", incoming_pdu_decoded);
502     printf_hexdump(&incoming_pdu_decoded->data[7], 2 + cypher_len);
503 
504     printf("RX-Decrypted: ");
505     printf_hexdump(incoming_pdu_decoded->data, incoming_pdu_decoded->len);
506 #endif
507 
508     // validate network mic
509     if (memcmp(net_mic, &incoming_pdu_raw->data[incoming_pdu_decoded->len-net_mic_len], net_mic_len) != 0){
510         // fail
511         printf("RX-NetMIC mismatch, try next key (%p)\n", incoming_pdu_decoded);
512         process_network_pdu_validate();
513         return;
514     }
515 
516     // remove NetMIC from payload
517     incoming_pdu_decoded->len -= net_mic_len;
518 
519 #ifdef LOG_NETWORK
520     // match
521     printf("RX-NetMIC matches (%p)\n", incoming_pdu_decoded);
522     printf("RX-TTL (%p): 0x%02x\n", incoming_pdu_decoded, incoming_pdu_decoded->data[1] & 0x7f);
523 #endif
524 
525     // set netkey_index
526     incoming_pdu_decoded->netkey_index = current_network_key->netkey_index;
527 
528     if (incoming_pdu_decoded->flags & MESH_NETWORK_PDU_FLAGS_PROXY_CONFIGURATION){
529 
530         mesh_network_pdu_t * decoded_pdu = incoming_pdu_decoded;
531         incoming_pdu_decoded = NULL;
532 
533         // no additional checks for proxy messages
534         (*mesh_network_proxy_message_handler)(MESH_NETWORK_PDU_RECEIVED, decoded_pdu);
535 
536     } else {
537 
538         // validate src/dest addresses
539         uint16_t src = big_endian_read_16(incoming_pdu_decoded->data, 5);
540         uint16_t dst = big_endian_read_16(incoming_pdu_decoded->data, 7);
541         int valid = mesh_network_addresses_valid(ctl, src, dst);
542         if (!valid){
543 #ifdef LOG_NETWORK
544             printf("RX Address invalid (%p)\n", incoming_pdu_decoded);
545 #endif
546             btstack_memory_mesh_network_pdu_free(incoming_pdu_decoded);
547             incoming_pdu_decoded = NULL;
548             process_network_pdu_done();
549             return;
550         }
551 
552         // check cache
553         uint32_t hash = mesh_network_cache_hash(incoming_pdu_decoded);
554 #ifdef LOG_NETWORK
555         printf("RX-Hash (%p): %08x\n", incoming_pdu_decoded, hash);
556 #endif
557         if (mesh_network_cache_find(hash)){
558             // found in cache, drop
559 #ifdef LOG_NETWORK
560             printf("Found in cache -> drop packet (%p)\n", incoming_pdu_decoded);
561 #endif
562             btstack_memory_mesh_network_pdu_free(incoming_pdu_decoded);
563             incoming_pdu_decoded = NULL;
564             process_network_pdu_done();
565             return;
566         }
567 
568         // store in network cache
569         mesh_network_cache_add(hash);
570 
571 #ifdef LOG_NETWORK
572             printf("RX-Validated (%p) - forward to lower transport\n", incoming_pdu_decoded);
573 #endif
574 
575         // forward to lower transport layer. message is freed by call to mesh_network_message_processed_by_upper_layer
576         mesh_network_pdu_t * decoded_pdu = incoming_pdu_decoded;
577         incoming_pdu_decoded = NULL;
578         (*mesh_network_higher_layer_handler)(MESH_NETWORK_PDU_RECEIVED, decoded_pdu);
579     }
580 
581     // done
582     process_network_pdu_done();
583 }
584 
585 static uint32_t iv_index_for_pdu(const mesh_network_pdu_t * network_pdu){
586     // get IV Index and IVI
587     uint32_t iv_index = mesh_get_iv_index();
588     int ivi = network_pdu->data[0] >> 7;
589 
590     // if least significant bit differs, use previous IV Index
591     if ((iv_index & 1 ) ^ ivi){
592         iv_index--;
593 #ifdef LOG_NETWORK
594         printf("RX-IV: IVI indicates previous IV index, using 0x%08x\n", iv_index);
595 #endif
596     }
597     return iv_index;
598 }
599 
600 static void process_network_pdu_validate_b(void * arg){
601     UNUSED(arg);
602 
603 #ifdef LOG_NETWORK
604     printf("RX-PECB: ");
605     printf_hexdump(obfuscation_block, 6);
606 #endif
607 
608     // de-obfuscate
609     unsigned int i;
610     for (i=0;i<6;i++){
611         incoming_pdu_decoded->data[1+i] = incoming_pdu_raw->data[1+i] ^ obfuscation_block[i];
612     }
613 
614     uint32_t iv_index = iv_index_for_pdu(incoming_pdu_raw);
615 
616     if (incoming_pdu_decoded->flags & MESH_NETWORK_PDU_FLAGS_PROXY_CONFIGURATION){
617         // create network nonce
618         mesh_proxy_create_nonce(network_nonce, incoming_pdu_decoded, iv_index);
619 #ifdef LOG_NETWORK
620         printf("RX-Proxy Nonce: ");
621         printf_hexdump(network_nonce, 13);
622 #endif
623     } else {
624         // create network nonce
625         mesh_network_create_nonce(network_nonce, incoming_pdu_decoded, iv_index);
626 #ifdef LOG_NETWORK
627         printf("RX-Network Nonce: ");
628         printf_hexdump(network_nonce, 13);
629 #endif
630     }
631 
632     //
633     uint8_t ctl_ttl     = incoming_pdu_decoded->data[1];
634     uint8_t net_mic_len = (ctl_ttl & 0x80) ? 8 : 4;
635     uint8_t cypher_len  = incoming_pdu_decoded->len - 7 - net_mic_len;
636 
637 #ifdef LOG_NETWORK
638     printf("RX-Cyper len %u, mic len %u\n", cypher_len, net_mic_len);
639 
640     printf("RX-Encryption Key: ");
641     printf_hexdump(current_network_key->encryption_key, 16);
642 
643 #endif
644 
645     btstack_crypto_ccm_init(&mesh_network_crypto_request.ccm, current_network_key->encryption_key, network_nonce, cypher_len, 0, net_mic_len);
646     btstack_crypto_ccm_decrypt_block(&mesh_network_crypto_request.ccm, cypher_len, &incoming_pdu_raw->data[7], &incoming_pdu_decoded->data[7], &process_network_pdu_validate_d, incoming_pdu_decoded);
647 }
648 
649 static void process_network_pdu_validate(void){
650     if (!mesh_network_key_nid_iterator_has_more(&validation_network_key_it)){
651         printf("No valid network key found\n");
652         btstack_memory_mesh_network_pdu_free(incoming_pdu_decoded);
653         incoming_pdu_decoded = NULL;
654         process_network_pdu_done();
655         return;
656     }
657 
658     current_network_key = mesh_network_key_nid_iterator_get_next(&validation_network_key_it);
659 
660     // calc PECB
661     uint32_t iv_index = iv_index_for_pdu(incoming_pdu_raw);
662     memset(encryption_block, 0, 5);
663     big_endian_store_32(encryption_block, 5, iv_index);
664     memcpy(&encryption_block[9], &incoming_pdu_raw->data[7], 7);
665     btstack_crypto_aes128_encrypt(&mesh_network_crypto_request.aes128, current_network_key->privacy_key, encryption_block, obfuscation_block, &process_network_pdu_validate_b, NULL);
666 }
667 
668 
669 static void process_network_pdu(void){
670     //
671     uint8_t nid_ivi = incoming_pdu_raw->data[0];
672 
673     // setup pdu object
674     incoming_pdu_decoded->data[0] = nid_ivi;
675     incoming_pdu_decoded->len     = incoming_pdu_raw->len;
676     incoming_pdu_decoded->flags   = incoming_pdu_raw->flags;
677 
678     // init provisioning data iterator
679     uint8_t nid = nid_ivi & 0x7f;
680     // uint8_t iv_index = network_pdu_data[0] >> 7;
681     mesh_network_key_nid_iterator_init(&validation_network_key_it, nid);
682 
683     process_network_pdu_validate();
684 }
685 
686 static void mesh_network_run(void){
687     if (!btstack_linked_list_empty(&network_pdus_outgoing_gatt)){
688 
689 
690 #ifdef ENABLE_MESH_GATT_BEARER
691         if (gatt_bearer_network_pdu == NULL){
692             // move to 'gatt bearer queue'
693             mesh_network_pdu_t * network_pdu = (mesh_network_pdu_t *) btstack_linked_list_pop(&network_pdus_outgoing_gatt);
694 
695 #ifdef LOG_NETWORK
696         printf("network run: pop %p from network_pdus_outgoing_gatt\n", network_pdu);
697 #endif
698         // request to send via gatt if:
699         // proxy active and connected
700         // packet wasn't received via gatt bearer
701             int send_via_gatt = ((mesh_foundation_gatt_proxy_get() != 0) &&
702             (gatt_bearer_con_handle != HCI_CON_HANDLE_INVALID) &&
703                                  ((network_pdu->flags & MESH_NETWORK_PDU_FLAGS_GATT_BEARER) == 0));
704             if (send_via_gatt){
705 #ifdef LOG_NETWORK
706         printf("network run: set %p as gatt_bearer_network_pdu\n", network_pdu);
707 #endif
708 
709                gatt_bearer_network_pdu = network_pdu;
710                 gatt_bearer_request_can_send_now_for_network_pdu();
711             } else {
712 #ifdef LOG_NETWORK
713         printf("network run: push %p to network_pdus_outgoing_adv\n", network_pdu);
714 #endif
715                 btstack_linked_list_add_tail(&network_pdus_outgoing_adv, (btstack_linked_item_t *) network_pdu);
716             }
717         }
718 #else
719         // directly move to 'outgoing adv bearer queue'
720         mesh_network_pdu_t * network_pdu = (mesh_network_pdu_t *) btstack_linked_list_pop(&network_pdus_outgoing_gatt);
721         btstack_linked_list_add_tail(&network_pdus_outgoing_adv, (btstack_linked_item_t *) network_pdu);
722 #endif
723     }
724 
725     if (!btstack_linked_list_empty(&network_pdus_outgoing_adv)){
726 #ifdef ENABLE_MESH_ADV_BEARER
727         if (adv_bearer_network_pdu == NULL){
728             // move to 'adv bearer queue'
729 #ifdef LOG_NETWORK
730             mesh_network_dump_network_pdus("network_pdus_outgoing_adv", &network_pdus_outgoing_adv);
731 #endif
732             mesh_network_pdu_t * network_pdu = (mesh_network_pdu_t *) btstack_linked_list_pop(&network_pdus_outgoing_adv);
733 #ifdef LOG_NETWORK
734             printf("network run: pop %p from network_pdus_outgoing_adv\n", network_pdu);
735             mesh_network_dump_network_pdus("network_pdus_outgoing_adv", &network_pdus_outgoing_adv);
736 #endif
737             adv_bearer_network_pdu = network_pdu;
738             adv_bearer_request_can_send_now_for_network_pdu();
739         }
740 #else
741         // done
742         mesh_network_pdu_t * network_pdu = (mesh_network_pdu_t *) btstack_linked_list_pop(&network_pdus_outgoing_adv);
743         // directly notify upper layer
744         mesh_network_send_complete(network_pdu);
745 #endif
746     }
747 
748     if (mesh_crypto_active) return;
749 
750     if (!btstack_linked_list_empty(&network_pdus_received)){
751         incoming_pdu_decoded = mesh_network_pdu_get();
752         if (!incoming_pdu_decoded) return;
753         // get encoded network pdu and start processing
754         mesh_crypto_active = 1;
755         incoming_pdu_raw = (mesh_network_pdu_t *) btstack_linked_list_pop(&network_pdus_received);
756         process_network_pdu();
757         return;
758     }
759 
760     if (!btstack_linked_list_empty(&network_pdus_queued)){
761         // get queued network pdu and start processing
762 #ifdef LOG_NETWORK
763         mesh_network_dump_network_pdus("network_pdus_queued", &network_pdus_queued);
764 #endif
765         outgoing_pdu = (mesh_network_pdu_t *) btstack_linked_list_pop(&network_pdus_queued);
766 #ifdef LOG_NETWORK
767         printf("network run: pop %p from network_pdus_queued\n", outgoing_pdu);
768         mesh_network_dump_network_pdus("network_pdus_queued", &network_pdus_queued);
769 #endif
770         mesh_network_send_a();
771         return;
772     }
773 }
774 
775 #ifdef ENABLE_MESH_ADV_BEARER
776 static void mesh_adv_bearer_handle_network_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
777     UNUSED(channel);
778     mesh_network_pdu_t * network_pdu;
779     uint8_t  transmission_count;
780     uint16_t transmission_interval;
781     uint8_t  transmit_config;
782 
783     switch (packet_type){
784         case MESH_NETWORK_PACKET:
785             // check len. minimal transport PDU len = 1, 32 bit NetMIC -> 13 bytes
786             if (size < 13) break;
787 
788 #ifdef LOG_NETWORK
789             printf("received network pdu from adv (len %u): ", size);
790             printf_hexdump(packet, size);
791 #endif
792             mesh_network_received_message(packet, size, 0);
793             break;
794 
795         case HCI_EVENT_PACKET:
796             switch(packet[0]){
797                 case HCI_EVENT_MESH_META:
798                     switch(packet[2]){
799                         case MESH_SUBEVENT_CAN_SEND_NOW:
800                             if (adv_bearer_network_pdu == NULL) break;
801 
802                             // Get Transmission config depending on relay flag
803                             if (adv_bearer_network_pdu->flags & MESH_NETWORK_PDU_FLAGS_RELAY){
804                                 transmit_config = mesh_foundation_relay_get();
805                             } else {
806                                 transmit_config = mesh_foundation_network_transmit_get();
807                             }
808                             transmission_count     = (transmit_config & 0x07) + 1;
809                             transmission_interval = (transmit_config >> 3) * 10;
810 
811 #ifdef LOG_NETWORK
812                             printf("TX-E-NetworkPDU count %u, interval %u ms (%p): ", transmission_count, transmission_interval, adv_bearer_network_pdu);
813                             printf_hexdump(adv_bearer_network_pdu->data, adv_bearer_network_pdu->len);
814 #endif
815 
816                             adv_bearer_send_network_pdu(adv_bearer_network_pdu->data, adv_bearer_network_pdu->len, transmission_count, transmission_interval);
817                             network_pdu = adv_bearer_network_pdu;
818                             adv_bearer_network_pdu = NULL;
819 
820                             // notify upper layer
821                             mesh_network_send_complete(network_pdu);
822 
823                             // check if more to send
824                             mesh_network_run();
825                             break;
826                         default:
827                             break;
828                     }
829                     break;
830                 default:
831                     break;
832             }
833             break;
834     }
835 }
836 #endif
837 
838 #ifdef ENABLE_MESH_GATT_BEARER
839 static void mesh_network_gatt_bearer_outgoing_complete(void){
840 
841     if (gatt_bearer_network_pdu == NULL) return;
842 
843     // forward to adv bearer
844     btstack_linked_list_add_tail(&network_pdus_outgoing_adv, (btstack_linked_item_t*) gatt_bearer_network_pdu);
845     gatt_bearer_network_pdu = NULL;
846 
847     mesh_network_run();
848     return;
849 }
850 
851 static void mesh_network_gatt_bearer_handle_network_event(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
852     UNUSED(channel);
853     switch (packet_type){
854         case MESH_PROXY_DATA_PACKET:
855             if (mesh_foundation_gatt_proxy_get() == 0) break;
856 #ifdef LOG_NETWORK
857             printf("received network pdu from gatt (len %u): ", size);
858             printf_hexdump(packet, size);
859 #endif
860             mesh_network_received_message(packet, size, MESH_NETWORK_PDU_FLAGS_GATT_BEARER);
861             break;
862         case HCI_EVENT_PACKET:
863             switch (hci_event_packet_get_type(packet)){
864                 case HCI_EVENT_MESH_META:
865                     switch (hci_event_mesh_meta_get_subevent_code(packet)){
866                         case MESH_SUBEVENT_PROXY_CONNECTED:
867                             gatt_bearer_con_handle = mesh_subevent_proxy_connected_get_con_handle(packet);
868                             break;
869                         case MESH_SUBEVENT_PROXY_DISCONNECTED:
870                             gatt_bearer_con_handle = HCI_CON_HANDLE_INVALID;
871                             mesh_network_gatt_bearer_outgoing_complete();
872                             break;
873                         case MESH_SUBEVENT_CAN_SEND_NOW:
874                             if (gatt_bearer_network_pdu == NULL) break;
875 #ifdef LOG_NETWORK
876                             printf("G-TX-E-NetworkPDU (%p): ", gatt_bearer_network_pdu);
877                             printf_hexdump(gatt_bearer_network_pdu->data, gatt_bearer_network_pdu->len);
878 #endif
879                             gatt_bearer_send_network_pdu(gatt_bearer_network_pdu->data, gatt_bearer_network_pdu->len);
880                             break;
881 
882                         case MESH_SUBEVENT_MESSAGE_SENT:
883                             mesh_network_gatt_bearer_outgoing_complete();
884                             break;
885                         default:
886                             break;
887                     }
888                     break;
889                 default:
890                     break;
891             }
892             break;
893         default:
894             break;
895     }
896 }
897 #endif
898 
899 #ifdef ENABLE_MESH_GATT_BEARER
900 static void mesh_netework_gatt_bearer_handle_proxy_configuration(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
901     UNUSED(channel);
902     switch (packet_type){
903         case MESH_PROXY_DATA_PACKET:
904             mesh_network_process_proxy_configuration_message(packet, size);
905             break;
906         case HCI_EVENT_PACKET:
907             switch (hci_event_packet_get_type(packet)){
908                 case HCI_EVENT_MESH_META:
909                     switch (hci_event_mesh_meta_get_subevent_code(packet)){
910                         case MESH_SUBEVENT_CAN_SEND_NOW:
911                             // forward to higher layer
912                             (*mesh_network_proxy_message_handler)(MESH_NETWORK_CAN_SEND_NOW, NULL);
913                             break;
914                         default:
915                             break;
916                     }
917                     break;
918                 default:
919                     break;
920             }
921             break;
922         default:
923             break;
924     }
925 }
926 #endif
927 
928 void mesh_network_init(void){
929 #ifdef ENABLE_MESH_ADV_BEARER
930     adv_bearer_register_for_network_pdu(&mesh_adv_bearer_handle_network_event);
931 #endif
932 #ifdef ENABLE_MESH_GATT_BEARER
933     gatt_bearer_con_handle = HCI_CON_HANDLE_INVALID;
934     gatt_bearer_register_for_network_pdu(&mesh_network_gatt_bearer_handle_network_event);
935     gatt_bearer_register_for_mesh_proxy_configuration(&mesh_netework_gatt_bearer_handle_proxy_configuration);
936 #endif
937 }
938 
939 void mesh_network_set_higher_layer_handler(void (*packet_handler)(mesh_network_callback_type_t callback_type, mesh_network_pdu_t * network_pdu)){
940     mesh_network_higher_layer_handler = packet_handler;
941 }
942 
943 void mesh_network_set_proxy_message_handler(void (*packet_handler)(mesh_network_callback_type_t callback_type, mesh_network_pdu_t * network_pdu)){
944     mesh_network_proxy_message_handler = packet_handler;
945 }
946 
947 void mesh_network_received_message(const uint8_t * pdu_data, uint8_t pdu_len, uint8_t flags){
948     // verify len
949     if (pdu_len > 29) return;
950 
951     // allocate network_pdu
952     mesh_network_pdu_t * network_pdu = mesh_network_pdu_get();
953     if (!network_pdu) return;
954 
955     // store data
956     memcpy(network_pdu->data, pdu_data, pdu_len);
957     network_pdu->len = pdu_len;
958     network_pdu->flags = flags;
959 
960     // add to list and go
961     btstack_linked_list_add_tail(&network_pdus_received, (btstack_linked_item_t *) network_pdu);
962     mesh_network_run();
963 
964 }
965 
966 void mesh_network_process_proxy_configuration_message(const uint8_t * pdu_data, uint8_t pdu_len){
967     // verify len
968     if (pdu_len > 29) return;
969 
970     // allocate network_pdu
971     mesh_network_pdu_t * network_pdu = mesh_network_pdu_get();
972     if (!network_pdu) return;
973 
974     // store data
975     memcpy(network_pdu->data, pdu_data, pdu_len);
976     network_pdu->len = pdu_len;
977     network_pdu->flags = MESH_NETWORK_PDU_FLAGS_PROXY_CONFIGURATION; // Network PDU
978 
979     // add to list and go
980     btstack_linked_list_add_tail(&network_pdus_received, (btstack_linked_item_t *) network_pdu);
981     mesh_network_run();
982 }
983 
984 void mesh_network_send_pdu(mesh_network_pdu_t * network_pdu){
985 #ifdef LOG_NETWORK
986     printf("TX-NetworkPDU (%p):   ", network_pdu);
987     printf_hexdump(network_pdu->data, network_pdu->len);
988     printf("^^ into network_pdus_queued\n");
989 #endif
990 
991     btstack_assert((network_pdu->len + (network_pdu->data[1] & 0x80 ? 8 : 4)) <= 29);
992     btstack_assert(network_pdu->len >= 9);
993 
994     // setup callback
995     network_pdu->callback = &mesh_network_send_d;
996     network_pdu->flags    = 0;
997 
998     // queue up
999     btstack_linked_list_add_tail(&network_pdus_queued, (btstack_linked_item_t *) network_pdu);
1000 #ifdef LOG_NETWORK
1001     mesh_network_dump_network_pdus("network_pdus_queued", &network_pdus_queued);
1002 #endif
1003 
1004     // go
1005     mesh_network_run();
1006 }
1007 
1008 void mesh_network_encrypt_proxy_configuration_message(mesh_network_pdu_t * network_pdu, void (* callback)(mesh_network_pdu_t * callback)){
1009     printf("ProxyPDU(unencrypted): ");
1010     printf_hexdump(network_pdu->data, network_pdu->len);
1011 
1012     // setup callback
1013     network_pdu->callback = callback;
1014     network_pdu->flags    = MESH_NETWORK_PDU_FLAGS_PROXY_CONFIGURATION;
1015 
1016     // queue up
1017     btstack_linked_list_add_tail(&network_pdus_queued, (btstack_linked_item_t *) network_pdu);
1018 
1019     // go
1020     mesh_network_run();
1021 }
1022 
1023 /*
1024  * @brief Setup network pdu header
1025  * @param netkey_index
1026  * @param ctl
1027  * @param ttl
1028  * @param seq
1029  * @param dest
1030  */
1031 void mesh_network_setup_pdu(mesh_network_pdu_t * network_pdu, uint16_t netkey_index, uint8_t nid, uint8_t ctl, uint8_t ttl, uint32_t seq, uint16_t src, uint16_t dest, const uint8_t * transport_pdu_data, uint8_t transport_pdu_len){
1032     memset(network_pdu, 0, sizeof(mesh_network_pdu_t));
1033     // set netkey_index
1034     network_pdu->netkey_index = netkey_index;
1035     // setup header
1036     network_pdu->data[network_pdu->len++] = (mesh_get_iv_index_for_tx() << 7) |  nid;
1037     uint8_t ctl_ttl = (ctl << 7) | (ttl & 0x7f);
1038     network_pdu->data[network_pdu->len++] = ctl_ttl;
1039     big_endian_store_24(network_pdu->data, 2, seq);
1040     network_pdu->len += 3;
1041     big_endian_store_16(network_pdu->data, network_pdu->len, src);
1042     network_pdu->len += 2;
1043     big_endian_store_16(network_pdu->data, network_pdu->len, dest);
1044     network_pdu->len += 2;
1045     memcpy(&network_pdu->data[network_pdu->len], transport_pdu_data, transport_pdu_len);
1046     network_pdu->len += transport_pdu_len;
1047 }
1048 
1049 /*
1050  * @brief Setup network pdu header
1051  * @param netkey_index
1052  * @param ctl
1053  * @param ttl
1054  * @param seq
1055  * @param dest
1056  */
1057 void mesh_network_setup_pdu_header(mesh_network_pdu_t * network_pdu, uint16_t netkey_index, uint8_t nid, uint8_t ctl, uint8_t ttl, uint32_t seq, uint16_t src, uint16_t dest){
1058     // set netkey_index
1059     network_pdu->netkey_index = netkey_index;
1060     // setup header
1061     network_pdu->data[0] = (mesh_get_iv_index_for_tx() << 7) |  nid;
1062     uint8_t ctl_ttl = (ctl << 7) | (ttl & 0x7f);
1063     network_pdu->data[1] = ctl_ttl;
1064     big_endian_store_24(network_pdu->data, 2, seq);
1065     big_endian_store_16(network_pdu->data, 5, src);
1066     big_endian_store_16(network_pdu->data, 7, dest);
1067 }
1068 
1069 // Network PDU Getter
1070 uint8_t  mesh_network_nid(mesh_network_pdu_t * network_pdu){
1071     return network_pdu->data[0] & 0x7f;
1072 }
1073 uint16_t mesh_network_control(mesh_network_pdu_t * network_pdu){
1074     return network_pdu->data[1] & 0x80;
1075 }
1076 uint8_t mesh_network_ttl(mesh_network_pdu_t * network_pdu){
1077     return network_pdu->data[1] & 0x7f;
1078 }
1079 uint32_t mesh_network_seq(mesh_network_pdu_t * network_pdu){
1080     return big_endian_read_24(network_pdu->data, 2);
1081 }
1082 uint16_t mesh_network_src(mesh_network_pdu_t * network_pdu){
1083     return big_endian_read_16(network_pdu->data, 5);
1084 }
1085 uint16_t mesh_network_dst(mesh_network_pdu_t * network_pdu){
1086     return big_endian_read_16(network_pdu->data, 7);
1087 }
1088 int mesh_network_segmented(mesh_network_pdu_t * network_pdu){
1089     return network_pdu->data[9] & 0x80;
1090 }
1091 uint8_t mesh_network_control_opcode(mesh_network_pdu_t * network_pdu){
1092     return network_pdu->data[9] & 0x7f;
1093 }
1094 uint8_t * mesh_network_pdu_data(mesh_network_pdu_t * network_pdu){
1095     return &network_pdu->data[9];
1096 }
1097 uint8_t   mesh_network_pdu_len(mesh_network_pdu_t * network_pdu){
1098     return network_pdu->len - 9;
1099 }
1100 
1101 static void mesh_network_dump_network_pdu(mesh_network_pdu_t * network_pdu){
1102     if (network_pdu){
1103         printf("- %p: ", network_pdu); printf_hexdump(network_pdu->data, network_pdu->len);
1104     }
1105 }
1106 static void mesh_network_dump_network_pdus(const char * name, btstack_linked_list_t * list){
1107     printf("List: %s:\n", name);
1108     btstack_linked_list_iterator_t it;
1109     btstack_linked_list_iterator_init(&it, list);
1110     while (btstack_linked_list_iterator_has_next(&it)){
1111         mesh_network_pdu_t * network_pdu = (mesh_network_pdu_t*) btstack_linked_list_iterator_next(&it);
1112         mesh_network_dump_network_pdu(network_pdu);
1113     }
1114 }
1115 static void mesh_network_reset_network_pdus(btstack_linked_list_t * list){
1116     while (!btstack_linked_list_empty(list)){
1117         mesh_network_pdu_t * pdu = (mesh_network_pdu_t *) btstack_linked_list_pop(list);
1118         btstack_memory_mesh_network_pdu_free(pdu);
1119     }
1120 }
1121 void mesh_network_dump(void){
1122     mesh_network_dump_network_pdus("network_pdus_received", &network_pdus_received);
1123     mesh_network_dump_network_pdus("network_pdus_queued", &network_pdus_queued);
1124     mesh_network_dump_network_pdus("network_pdus_outgoing_gatt", &network_pdus_outgoing_gatt);
1125     mesh_network_dump_network_pdus("network_pdus_outgoing_adv", &network_pdus_outgoing_adv);
1126     printf("outgoing_pdu: \n");
1127     mesh_network_dump_network_pdu(outgoing_pdu);
1128     printf("incoming_pdu_raw: \n");
1129     mesh_network_dump_network_pdu(incoming_pdu_raw);
1130 #ifdef ENABLE_MESH_GATT_BEARER
1131     printf("gatt_bearer_network_pdu: \n");
1132     mesh_network_dump_network_pdu(gatt_bearer_network_pdu);
1133 #endif
1134 #ifdef ENABLE_MESH_ADV_BEARER
1135     printf("adv_bearer_network_pdu: \n");
1136     mesh_network_dump_network_pdu(adv_bearer_network_pdu);
1137 #endif
1138 
1139 }
1140 void mesh_network_reset(void){
1141     mesh_network_reset_network_pdus(&network_pdus_received);
1142     mesh_network_reset_network_pdus(&network_pdus_queued);
1143     mesh_network_reset_network_pdus(&network_pdus_outgoing_gatt);
1144     mesh_network_reset_network_pdus(&network_pdus_outgoing_adv);
1145 
1146     // outgoing network pdus are owned by higher layer, so we don't free:
1147     // - adv_bearer_network_pdu
1148     // - gatt_bearer_network_pdu
1149     // - outoing_pdu
1150 #ifdef ENABLE_MESH_ADV_BEARER
1151     adv_bearer_network_pdu = NULL;
1152 #endif
1153 #ifdef ENABLE_MESH_GATT_BEARER
1154     gatt_bearer_network_pdu = NULL;
1155 #endif
1156     outgoing_pdu = NULL;
1157 
1158     if (incoming_pdu_raw){
1159         mesh_network_pdu_free(incoming_pdu_raw);
1160         incoming_pdu_raw = NULL;
1161     }
1162     if (incoming_pdu_decoded){
1163         mesh_network_pdu_free(incoming_pdu_decoded);
1164         incoming_pdu_decoded = NULL;
1165     }
1166     mesh_crypto_active = 0;
1167 }
1168 
1169 // buffer pool
1170 mesh_network_pdu_t * mesh_network_pdu_get(void){
1171     mesh_network_pdu_t * network_pdu = btstack_memory_mesh_network_pdu_get();
1172     if (network_pdu) {
1173         memset(network_pdu, 0, sizeof(mesh_network_pdu_t));
1174         network_pdu->pdu_header.pdu_type = MESH_PDU_TYPE_NETWORK;
1175     }
1176     return network_pdu;
1177 }
1178 
1179 void mesh_network_pdu_free(mesh_network_pdu_t * network_pdu){
1180     btstack_memory_mesh_network_pdu_free(network_pdu);
1181 }
1182 
1183 // Mesh Subnet Management
1184 
1185 void mesh_subnet_add(mesh_subnet_t * subnet){
1186     btstack_linked_list_add_tail(&subnets, (btstack_linked_item_t *) subnet);
1187 }
1188 
1189 void mesh_subnet_remove(mesh_subnet_t * subnet){
1190     btstack_linked_list_remove(&subnets, (btstack_linked_item_t *) subnet);
1191 }
1192 
1193 mesh_subnet_t * mesh_subnet_get_by_netkey_index(uint16_t netkey_index){
1194     btstack_linked_list_iterator_t it;
1195     btstack_linked_list_iterator_init(&it, &subnets);
1196     while (btstack_linked_list_iterator_has_next(&it)){
1197         mesh_subnet_t * item = (mesh_subnet_t *) btstack_linked_list_iterator_next(&it);
1198         if (item->netkey_index == netkey_index) return item;
1199     }
1200     return NULL;
1201 }
1202 
1203 int mesh_subnet_list_count(void){
1204     return btstack_linked_list_count(&subnets);
1205 }
1206 
1207 // mesh network key iterator over all keys
1208 void mesh_subnet_iterator_init(mesh_subnet_iterator_t *it){
1209     btstack_linked_list_iterator_init(&it->it, &subnets);
1210 }
1211 
1212 int mesh_subnet_iterator_has_more(mesh_subnet_iterator_t *it){
1213     return btstack_linked_list_iterator_has_next(&it->it);
1214 }
1215 
1216 mesh_subnet_t * mesh_subnet_iterator_get_next(mesh_subnet_iterator_t *it){
1217     return (mesh_subnet_t *) btstack_linked_list_iterator_next(&it->it);
1218 }
1219 
1220 mesh_network_key_t * mesh_subnet_get_outgoing_network_key(mesh_subnet_t * subnet){
1221     switch (subnet->key_refresh){
1222         case MESH_KEY_REFRESH_SECOND_PHASE:
1223             return subnet->new_key;
1224         case MESH_KEY_REFRESH_NOT_ACTIVE:
1225         case MESH_KEY_REFRESH_FIRST_PHASE:
1226         default:
1227             return subnet->old_key;
1228     }
1229 }
1230 
1231 /**
1232  * @brief Setup subnet for given netkey index
1233  */
1234 void mesh_subnet_setup_for_netkey_index(uint16_t netkey_index){
1235     mesh_subnet_t * subnet = mesh_subnet_get_by_netkey_index(netkey_index);
1236     if (subnet != NULL) return;
1237 
1238     // find old / new keys
1239     mesh_network_key_t * old_key = NULL;
1240     mesh_network_key_t * new_key = NULL;
1241     mesh_network_key_iterator_t it;
1242     mesh_network_key_iterator_init(&it);
1243     while (mesh_network_key_iterator_has_more(&it)){
1244         mesh_network_key_t * network_key = mesh_network_key_iterator_get_next(&it);
1245         if (network_key->netkey_index != netkey_index) continue;
1246         if (old_key == NULL){
1247             old_key = network_key;
1248             continue;
1249         }
1250         // assign current key depending on key version
1251         if (((int8_t) (network_key->version - new_key->version)) > 0) {
1252             new_key = network_key;
1253         } else {
1254             new_key = old_key;
1255             old_key = network_key;
1256         }
1257     }
1258 
1259     // create subnet for netkey index
1260     subnet = btstack_memory_mesh_subnet_get();
1261     if (subnet == NULL) return;
1262     subnet->netkey_index = netkey_index;
1263     mesh_subnet_add(subnet);
1264 
1265     // set keys
1266     subnet->old_key = old_key;
1267     subnet->new_key = new_key;
1268 
1269     // key refresh
1270     if (new_key == NULL){
1271         // single key -> key refresh not active
1272         subnet->key_refresh = MESH_KEY_REFRESH_NOT_ACTIVE;
1273     }
1274     else {
1275         // two keys -> at least phase 1
1276         subnet->key_refresh = MESH_KEY_REFRESH_FIRST_PHASE;
1277     }
1278 }
1279