xref: /btstack/src/mesh/mesh_upper_transport.c (revision 8ec600ff6d2f08cd691546a8bb6a052ae7e90983)
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_upper_transport.c"
39 
40 #include "mesh/mesh_upper_transport.h"
41 
42 #include <stdio.h>
43 #include <stdlib.h>
44 #include <string.h>
45 
46 #include "btstack_util.h"
47 #include "btstack_memory.h"
48 #include "btstack_debug.h"
49 
50 #include "mesh/beacon.h"
51 #include "mesh/mesh_iv_index_seq_number.h"
52 #include "mesh/mesh_keys.h"
53 #include "mesh/mesh_lower_transport.h"
54 #include "mesh/mesh_peer.h"
55 #include "mesh/mesh_virtual_addresses.h"
56 
57 // TODO: extract mesh_pdu functions into lower transport or network
58 #include "mesh/mesh_access.h"
59 
60 // combined key x address iterator for upper transport decryption
61 
62 typedef struct {
63     // state
64     mesh_transport_key_iterator_t  key_it;
65     mesh_virtual_address_iterator_t address_it;
66     // elements
67     const mesh_transport_key_t *   key;
68     const mesh_virtual_address_t * address;
69     // address - might be virtual
70     uint16_t dst;
71     // key info
72 } mesh_transport_key_and_virtual_address_iterator_t;
73 
74 static void mesh_upper_transport_validate_segmented_message(void);
75 static void mesh_upper_transport_run(void);
76 
77 static int crypto_active;
78 
79 static mesh_unsegmented_pdu_t * incoming_unsegmented_pdu_raw;
80 
81 static mesh_segmented_pdu_t     incoming_message_pdu_singleton;
82 
83 static mesh_access_pdu_t *      incoming_access_pdu_encrypted;
84 static mesh_access_pdu_t *      incoming_access_pdu_decrypted;
85 
86 static mesh_access_pdu_t        incoming_access_pdu_encrypted_singleton;
87 static mesh_access_pdu_t        incoming_access_pdu_decrypted_singleton;
88 
89 static mesh_control_pdu_t       incoming_control_pdu_singleton;
90 static mesh_control_pdu_t *     incoming_control_pdu;
91 
92 static mesh_segmented_pdu_t     outgoing_segmented_message_singleton;
93 static mesh_access_pdu_t *      outgoing_segmented_access_pdu;
94 
95 static mesh_unsegmented_pdu_t   outgoing_unsegmented_pdu_singleton;
96 static mesh_upper_transport_pdu_t  * outgoing_upper_transport_pdu;
97 
98 static uint8_t application_nonce[13];
99 static btstack_crypto_ccm_t ccm;
100 static uint8_t crypto_buffer[MESH_ACCESS_PAYLOAD_MAX];
101 static mesh_transport_key_and_virtual_address_iterator_t mesh_transport_key_it;
102 
103 // upper transport callbacks - in access layer
104 static void (*mesh_access_message_handler)( mesh_transport_callback_type_t callback_type, mesh_transport_status_t status, mesh_pdu_t * pdu);
105 static void (*mesh_control_message_handler)( mesh_transport_callback_type_t callback_type, mesh_transport_status_t status, mesh_pdu_t * pdu);
106 
107 // incoming unsegmented (network) and segmented (transport) control and access messages
108 static btstack_linked_list_t upper_transport_incoming;
109 
110 // outgoing unsegmented (network) and segmented (uppert_transport_outgoing) control and access messages
111 static btstack_linked_list_t upper_transport_outgoing;
112 
113 
114 // TODO: higher layer define used for assert
115 #define MESH_ACCESS_OPCODE_NOT_SET 0xFFFFFFFEu
116 
117 void mesh_upper_transport_send_access_pdu(mesh_pdu_t *pdu){
118     switch (pdu->pdu_type){
119         case MESH_PDU_TYPE_UPPER_SEGMENTED_ACCESS:
120         case MESH_PDU_TYPE_UPPER_UNSEGMENTED_ACCESS:
121             break;
122         default:
123             btstack_assert(false);
124             break;
125     }
126 
127     btstack_linked_list_add_tail(&upper_transport_outgoing, (btstack_linked_item_t*) pdu);
128     mesh_upper_transport_run();
129 }
130 
131 void mesh_upper_transport_send_control_pdu(mesh_pdu_t * pdu){
132     switch (pdu->pdu_type){
133         case MESH_PDU_TYPE_UPPER_SEGMENTED_CONTROL:
134             break;
135         case MESH_PDU_TYPE_UPPER_UNSEGMENTED_CONTROL:
136             btstack_assert( ((mesh_network_pdu_t *) pdu)->len >= 9);
137             break;
138         default:
139             btstack_assert(false);
140             break;
141     }
142 
143     btstack_linked_list_add_tail(&upper_transport_outgoing, (btstack_linked_item_t*) pdu);
144     mesh_upper_transport_run();
145 }
146 
147 static void mesh_print_hex(const char * name, const uint8_t * data, uint16_t len){
148     printf("%-20s ", name);
149     printf_hexdump(data, len);
150 }
151 // static void mesh_print_x(const char * name, uint32_t value){
152 //     printf("%20s: 0x%x", name, (int) value);
153 // }
154 
155 static void mesh_transport_key_and_virtual_address_iterator_init(mesh_transport_key_and_virtual_address_iterator_t *it,
156                                                                  uint16_t dst, uint16_t netkey_index, uint8_t akf,
157                                                                  uint8_t aid) {
158     printf("KEY_INIT: dst %04x, akf %x, aid %x\n", dst, akf, aid);
159     // config
160     it->dst   = dst;
161     // init elements
162     it->key     = NULL;
163     it->address = NULL;
164     // init element iterators
165     mesh_transport_key_aid_iterator_init(&it->key_it, netkey_index, akf, aid);
166     // init address iterator
167     if (mesh_network_address_virtual(it->dst)){
168         mesh_virtual_address_iterator_init(&it->address_it, dst);
169         // get first key
170         if (mesh_transport_key_aid_iterator_has_more(&it->key_it)) {
171             it->key = mesh_transport_key_aid_iterator_get_next(&it->key_it);
172         }
173     }
174 }
175 
176 // cartesian product: keys x addressses
177 static int mesh_transport_key_and_virtual_address_iterator_has_more(mesh_transport_key_and_virtual_address_iterator_t * it){
178     if (mesh_network_address_virtual(it->dst)) {
179         // find next valid entry
180         while (true){
181             if (mesh_virtual_address_iterator_has_more(&it->address_it)) return 1;
182             if (!mesh_transport_key_aid_iterator_has_more(&it->key_it)) return 0;
183             // get next key
184             it->key = mesh_transport_key_aid_iterator_get_next(&it->key_it);
185             mesh_virtual_address_iterator_init(&it->address_it, it->dst);
186         }
187     } else {
188         return mesh_transport_key_aid_iterator_has_more(&it->key_it);
189     }
190 }
191 
192 static void mesh_transport_key_and_virtual_address_iterator_next(mesh_transport_key_and_virtual_address_iterator_t * it){
193     if (mesh_network_address_virtual(it->dst)) {
194         it->address = mesh_virtual_address_iterator_get_next(&it->address_it);
195     } else {
196         it->key = mesh_transport_key_aid_iterator_get_next(&it->key_it);
197     }
198 }
199 
200 // UPPER TRANSPORT
201 
202 uint16_t mesh_access_dst(mesh_access_pdu_t * access_pdu){
203     return big_endian_read_16(access_pdu->network_header, 7);
204 }
205 
206 uint16_t mesh_access_ctl(mesh_access_pdu_t * access_pdu){
207     return access_pdu->network_header[1] >> 7;
208 }
209 
210 uint32_t mesh_access_seq(mesh_access_pdu_t * access_pdu){
211     return big_endian_read_24(access_pdu->network_header, 2);
212 }
213 
214 void mesh_access_set_nid_ivi(mesh_access_pdu_t * access_pdu, uint8_t nid_ivi){
215     access_pdu->network_header[0] = nid_ivi;
216 }
217 void mesh_access_set_ctl_ttl(mesh_access_pdu_t * access_pdu, uint8_t ctl_ttl){
218     access_pdu->network_header[1] = ctl_ttl;
219 }
220 void mesh_access_set_seq(mesh_access_pdu_t * access_pdu, uint32_t seq){
221     big_endian_store_24(access_pdu->network_header, 2, seq);
222 }
223 void mesh_access_set_src(mesh_access_pdu_t * access_pdu, uint16_t src){
224     big_endian_store_16(access_pdu->network_header, 5, src);
225 }
226 void mesh_access_set_dest(mesh_access_pdu_t * access_pdu, uint16_t dest){
227     big_endian_store_16(access_pdu->network_header, 7, dest);
228 }
229 
230 static void mesh_segmented_pdu_flatten(btstack_linked_list_t * segments, uint8_t segment_len, uint8_t * buffer) {
231     // assemble payload
232     btstack_linked_list_iterator_t it;
233     btstack_linked_list_iterator_init(&it, segments);
234     while (btstack_linked_list_iterator_has_next(&it)) {
235         mesh_network_pdu_t *segment = (mesh_network_pdu_t *) btstack_linked_list_iterator_next(&it);
236         btstack_assert(segment->pdu_header.pdu_type == MESH_PDU_TYPE_NETWORK);
237         // get segment n
238         uint8_t *lower_transport_pdu = mesh_network_pdu_data(segment);
239         uint8_t seg_o = (big_endian_read_16(lower_transport_pdu, 2) >> 5) & 0x001f;
240         uint8_t *segment_data = &lower_transport_pdu[4];
241         (void) memcpy(&buffer[seg_o * segment_len], segment_data, segment_len);
242     }
243 }
244 
245 static uint16_t mesh_upper_pdu_flatten(mesh_upper_transport_pdu_t * upper_pdu, uint8_t * buffer, uint16_t buffer_len) {
246     // assemble payload
247     btstack_linked_list_iterator_t it;
248     btstack_linked_list_iterator_init(&it, &upper_pdu->segments);
249     uint16_t offset = 0;
250     while (btstack_linked_list_iterator_has_next(&it)) {
251         mesh_network_pdu_t *segment = (mesh_network_pdu_t *) btstack_linked_list_iterator_next(&it);
252         btstack_assert(segment->pdu_header.pdu_type == MESH_PDU_TYPE_NETWORK);
253         btstack_assert((offset + segment->len) <= buffer_len);
254         (void) memcpy(&buffer[offset], segment->data, segment->len);
255         offset += segment->len;
256     }
257     return offset;
258 }
259 
260 static void mesh_segmented_append_payload(const uint8_t * payload, uint16_t payload_len, btstack_linked_list_t * segments){
261     uint16_t payload_offset = 0;
262     uint16_t bytes_current_segment = 0;
263     mesh_network_pdu_t * network_pdu = (mesh_network_pdu_t *) btstack_linked_list_get_last_item(segments);
264     if (network_pdu){
265         bytes_current_segment = MESH_NETWORK_PAYLOAD_MAX - network_pdu->len;
266     }
267     while (payload_offset < payload_len){
268         if (bytes_current_segment == 0){
269             network_pdu = mesh_network_pdu_get();
270             btstack_assert(network_pdu != NULL);
271             btstack_linked_list_add_tail(segments, (btstack_linked_item_t *) network_pdu);
272             bytes_current_segment = MESH_NETWORK_PAYLOAD_MAX;
273         }
274         uint16_t bytes_to_copy = btstack_min(bytes_current_segment, payload_len - payload_offset);
275         (void) memcpy(&network_pdu->data[network_pdu->len], &payload[payload_offset], bytes_to_copy);
276         bytes_current_segment -= bytes_to_copy;
277         network_pdu->len += bytes_to_copy;
278         payload_offset += bytes_to_copy;
279     }
280 }
281 
282 // stub lower transport
283 
284 static void mesh_upper_transport_dump_pdus(const char *name, btstack_linked_list_t *list){
285     printf("List: %s:\n", name);
286     btstack_linked_list_iterator_t it;
287     btstack_linked_list_iterator_init(&it, list);
288     while (btstack_linked_list_iterator_has_next(&it)){
289         mesh_pdu_t * pdu = (mesh_pdu_t*) btstack_linked_list_iterator_next(&it);
290         printf("- %p\n", pdu);
291         // printf_hexdump( mesh_pdu_data(pdu), mesh_pdu_len(pdu));
292     }
293 }
294 
295 static void mesh_upper_transport_reset_pdus(btstack_linked_list_t *list){
296     while (!btstack_linked_list_empty(list)){
297         mesh_upper_transport_pdu_free((mesh_pdu_t *) btstack_linked_list_pop(list));
298     }
299 }
300 
301 void mesh_upper_transport_dump(void){
302     printf("incoming_unsegmented_pdu_raw: %p\n", incoming_unsegmented_pdu_raw);
303     mesh_upper_transport_dump_pdus("upper_transport_incoming", &upper_transport_incoming);
304 }
305 
306 void mesh_upper_transport_reset(void){
307     crypto_active = 0;
308     if (incoming_unsegmented_pdu_raw){
309         mesh_network_pdu_t * network_pdu = incoming_unsegmented_pdu_raw->segment;
310         btstack_assert(network_pdu != NULL);
311         incoming_unsegmented_pdu_raw->segment = NULL;
312         mesh_network_pdu_free(network_pdu);
313         incoming_unsegmented_pdu_raw = NULL;
314     }
315     outgoing_segmented_access_pdu = NULL;
316     mesh_upper_transport_reset_pdus(&upper_transport_incoming);
317 }
318 
319 static uint32_t iv_index_for_ivi_nid(uint8_t ivi_nid){
320     // get IV Index and IVI
321     uint32_t iv_index = mesh_get_iv_index();
322     int ivi = ivi_nid >> 7;
323 
324     // if least significant bit differs, use previous IV Index
325     if ((iv_index & 1 ) ^ ivi){
326         iv_index--;
327     }
328     return iv_index;
329 }
330 
331 static void transport_segmented_setup_nonce(uint8_t * nonce, const mesh_pdu_t * pdu){
332     mesh_access_pdu_t * access_pdu;
333     mesh_upper_transport_pdu_t * upper_pdu;
334     switch (pdu->pdu_type){
335         case MESH_PDU_TYPE_ACCESS:
336             access_pdu = (mesh_access_pdu_t *) pdu;
337             nonce[1] = access_pdu->transmic_len == 8 ? 0x80 : 0x00;
338             (void)memcpy(&nonce[2], &access_pdu->network_header[2], 7);
339             big_endian_store_32(nonce, 9, iv_index_for_ivi_nid(access_pdu->network_header[0]));
340             break;
341         case MESH_PDU_TYPE_UPPER_SEGMENTED_ACCESS:
342         case MESH_PDU_TYPE_UPPER_UNSEGMENTED_ACCESS:
343             upper_pdu = (mesh_upper_transport_pdu_t *) pdu;
344             nonce[1] = upper_pdu->transmic_len == 8 ? 0x80 : 0x00;
345             // 'network header'
346             big_endian_store_24(nonce, 2, upper_pdu->seq);
347             big_endian_store_16(nonce, 5, upper_pdu->src);
348             big_endian_store_16(nonce, 7, upper_pdu->dst);
349             big_endian_store_32(nonce, 9, iv_index_for_ivi_nid(upper_pdu->ivi_nid));
350             break;
351         default:
352             btstack_assert(0);
353             break;
354     }
355 }
356 
357 static void transport_segmented_setup_application_nonce(uint8_t * nonce, const mesh_pdu_t * pdu){
358     nonce[0] = 0x01;
359     transport_segmented_setup_nonce(nonce, pdu);
360     mesh_print_hex("AppNonce", nonce, 13);
361 }
362 
363 static void transport_segmented_setup_device_nonce(uint8_t * nonce, const mesh_pdu_t * pdu){
364     nonce[0] = 0x02;
365     transport_segmented_setup_nonce(nonce, pdu);
366     mesh_print_hex("DeviceNonce", nonce, 13);
367 }
368 
369 static void mesh_upper_transport_process_message_done(mesh_segmented_pdu_t *message_pdu){
370     crypto_active = 0;
371     btstack_assert(message_pdu == &incoming_message_pdu_singleton);
372     mesh_network_pdu_t * network_pdu = (mesh_network_pdu_t *) btstack_linked_list_pop(&incoming_message_pdu_singleton.segments);
373     if (mesh_network_control(network_pdu)) {
374         btstack_assert(0);
375     } else {
376         btstack_assert(network_pdu != NULL);
377         mesh_network_pdu_free(network_pdu);
378         mesh_pdu_t * pdu = (mesh_pdu_t *) incoming_unsegmented_pdu_raw;
379         incoming_unsegmented_pdu_raw = NULL;
380         mesh_lower_transport_message_processed_by_higher_layer(pdu);
381     }
382     mesh_upper_transport_run();
383 }
384 
385 static void mesh_upper_transport_process_unsegmented_message_done(mesh_pdu_t * pdu){
386     btstack_assert(pdu != NULL);
387     btstack_assert(pdu->pdu_type == MESH_PDU_TYPE_UNSEGMENTED);
388 
389     mesh_unsegmented_pdu_t * unsegmented_incoming_pdu = (mesh_unsegmented_pdu_t *) pdu;
390     btstack_assert(unsegmented_incoming_pdu == incoming_unsegmented_pdu_raw);
391 
392     crypto_active = 0;
393     incoming_unsegmented_pdu_raw = NULL;
394     mesh_network_pdu_t * network_pdu = unsegmented_incoming_pdu->segment;
395     if (!mesh_network_control(network_pdu)) {
396         mesh_network_pdu_free(network_pdu);
397     }
398 
399     mesh_lower_transport_message_processed_by_higher_layer(pdu);
400     mesh_upper_transport_run();
401 }
402 
403 static void mesh_upper_transport_process_access_message_done(mesh_access_pdu_t *access_pdu){
404     crypto_active = 0;
405     btstack_assert(mesh_access_ctl(access_pdu) == 0);
406     incoming_access_pdu_encrypted = NULL;
407     mesh_upper_transport_run();
408 }
409 
410 static void mesh_upper_transport_process_control_message_done(mesh_control_pdu_t * control_pdu){
411     crypto_active = 0;
412     incoming_control_pdu = NULL;
413     mesh_upper_transport_run();
414 }
415 
416 static void mesh_upper_transport_validate_segmented_message_ccm(void * arg){
417     UNUSED(arg);
418 
419     uint8_t * upper_transport_pdu     = incoming_access_pdu_decrypted->data;
420     uint8_t   upper_transport_pdu_len = incoming_access_pdu_decrypted->len - incoming_access_pdu_decrypted->transmic_len;
421 
422     mesh_print_hex("Decrypted PDU", upper_transport_pdu, upper_transport_pdu_len);
423 
424     // store TransMIC
425     uint8_t trans_mic[8];
426     btstack_crypto_ccm_get_authentication_value(&ccm, trans_mic);
427     mesh_print_hex("TransMIC", trans_mic, incoming_access_pdu_decrypted->transmic_len);
428 
429     if (memcmp(trans_mic, &upper_transport_pdu[upper_transport_pdu_len], incoming_access_pdu_decrypted->transmic_len) == 0){
430         printf("TransMIC matches\n");
431 
432         // remove TransMIC from payload
433         incoming_access_pdu_decrypted->len -= incoming_access_pdu_decrypted->transmic_len;
434 
435         // if virtual address, update dst to pseudo_dst
436         if (mesh_network_address_virtual(mesh_access_dst(incoming_access_pdu_decrypted))){
437             big_endian_store_16(incoming_access_pdu_decrypted->network_header, 7, mesh_transport_key_it.address->pseudo_dst);
438         }
439 
440         // pass to upper layer
441         btstack_assert(mesh_access_message_handler != NULL);
442         mesh_pdu_t * pdu = (mesh_pdu_t*) incoming_access_pdu_decrypted;
443         mesh_access_message_handler(MESH_TRANSPORT_PDU_RECEIVED, MESH_TRANSPORT_STATUS_SUCCESS, pdu);
444 
445         printf("\n");
446 
447     } else {
448         uint8_t akf = incoming_access_pdu_decrypted->akf_aid_control & 0x40;
449         if (akf){
450             printf("TransMIC does not match, try next key\n");
451             mesh_upper_transport_validate_segmented_message();
452         } else {
453             printf("TransMIC does not match device key, done\n");
454             // done
455             mesh_upper_transport_process_access_message_done(incoming_access_pdu_decrypted);
456         }
457     }
458 }
459 
460 static void mesh_upper_transport_validate_segmented_message_digest(void * arg){
461     UNUSED(arg);
462     uint8_t   upper_transport_pdu_len      = incoming_access_pdu_encrypted->len - incoming_access_pdu_encrypted->transmic_len;
463     uint8_t * upper_transport_pdu_data_in  = incoming_access_pdu_encrypted->data;
464     uint8_t * upper_transport_pdu_data_out = incoming_access_pdu_decrypted->data;
465     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, NULL);
466 }
467 
468 static void mesh_upper_transport_validate_segmented_message(void){
469     uint8_t * upper_transport_pdu_data =  incoming_access_pdu_decrypted->data;
470     uint8_t   upper_transport_pdu_len  = incoming_access_pdu_decrypted->len - incoming_access_pdu_decrypted->transmic_len;
471 
472     if (!mesh_transport_key_and_virtual_address_iterator_has_more(&mesh_transport_key_it)){
473         printf("No valid transport key found\n");
474         mesh_upper_transport_process_access_message_done(incoming_access_pdu_decrypted);
475         return;
476     }
477     mesh_transport_key_and_virtual_address_iterator_next(&mesh_transport_key_it);
478     const mesh_transport_key_t * message_key = mesh_transport_key_it.key;
479 
480     if (message_key->akf){
481         transport_segmented_setup_application_nonce(application_nonce, (mesh_pdu_t *) incoming_access_pdu_encrypted);
482     } else {
483         transport_segmented_setup_device_nonce(application_nonce, (mesh_pdu_t *) incoming_access_pdu_encrypted);
484     }
485 
486     // store application / device key index
487     mesh_print_hex("AppOrDevKey", message_key->key, 16);
488     incoming_access_pdu_decrypted->appkey_index = message_key->appkey_index;
489 
490     mesh_print_hex("EncAccessPayload", upper_transport_pdu_data, upper_transport_pdu_len);
491 
492     // decrypt ccm
493     crypto_active = 1;
494     uint16_t aad_len  = 0;
495     if (mesh_network_address_virtual(mesh_access_dst(incoming_access_pdu_decrypted))){
496         aad_len  = 16;
497     }
498     btstack_crypto_ccm_init(&ccm, message_key->key, application_nonce, upper_transport_pdu_len, aad_len, incoming_access_pdu_decrypted->transmic_len);
499 
500     if (aad_len){
501         btstack_crypto_ccm_digest(&ccm, (uint8_t *) mesh_transport_key_it.address->label_uuid, aad_len, &mesh_upper_transport_validate_segmented_message_digest, NULL);
502     } else {
503         mesh_upper_transport_validate_segmented_message_digest(NULL);
504     }
505 }
506 
507 static void mesh_upper_transport_process_segmented_message(void){
508     // copy original pdu
509     (void)memcpy(incoming_access_pdu_decrypted, incoming_access_pdu_encrypted,
510                  sizeof(mesh_access_pdu_t));
511 
512     //
513     uint8_t * upper_transport_pdu     =  incoming_access_pdu_decrypted->data;
514     uint8_t   upper_transport_pdu_len = incoming_access_pdu_decrypted->len - incoming_access_pdu_decrypted->transmic_len;
515     mesh_print_hex("Upper Transport pdu", upper_transport_pdu, upper_transport_pdu_len);
516 
517     uint8_t aid = incoming_access_pdu_decrypted->akf_aid_control & 0x3f;
518     uint8_t akf = (incoming_access_pdu_decrypted->akf_aid_control & 0x40) >> 6;
519 
520     printf("AKF: %u\n",   akf);
521     printf("AID: %02x\n", aid);
522 
523     mesh_transport_key_and_virtual_address_iterator_init(&mesh_transport_key_it, mesh_access_dst(incoming_access_pdu_decrypted),
524                                                          incoming_access_pdu_decrypted->netkey_index, akf, aid);
525     mesh_upper_transport_validate_segmented_message();
526 }
527 
528 static void mesh_upper_transport_message_received(mesh_pdu_t * pdu){
529     btstack_linked_list_add_tail(&upper_transport_incoming, (btstack_linked_item_t*) pdu);
530     mesh_upper_transport_run();
531 }
532 
533 static void mesh_upper_transport_send_segmented_pdu(mesh_access_pdu_t * access_pdu){
534     outgoing_segmented_access_pdu = access_pdu;
535     mesh_segmented_pdu_t * message_pdu   = &outgoing_segmented_message_singleton;
536     message_pdu->pdu_header.pdu_type = MESH_PDU_TYPE_SEGMENTED;
537 
538     // convert mesh_access_pdu_t into mesh_segmented_pdu_t
539     mesh_segmented_append_payload(access_pdu->data, access_pdu->len, &message_pdu->segments);
540 
541     // copy meta
542     message_pdu->len = access_pdu->len;
543     message_pdu->netkey_index = access_pdu->netkey_index;
544     message_pdu->transmic_len = access_pdu->transmic_len;
545     message_pdu->akf_aid_control = access_pdu->akf_aid_control;
546     message_pdu->flags = access_pdu->flags;
547     (void)memcpy(message_pdu->network_header, access_pdu->network_header, 9);
548 
549     mesh_lower_transport_send_pdu((mesh_pdu_t*) message_pdu);
550 }
551 
552 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,
553                           const uint8_t * control_pdu_data, uint16_t control_pdu_len){
554 
555     if (control_pdu_len > 11) return 1;
556 
557     const mesh_network_key_t * network_key = mesh_network_key_list_get(netkey_index);
558     if (!network_key) return 1;
559 
560     uint8_t transport_pdu_data[12];
561     transport_pdu_data[0] = opcode;
562     (void)memcpy(&transport_pdu_data[1], control_pdu_data, control_pdu_len);
563     uint16_t transport_pdu_len = control_pdu_len + 1;
564 
565     // setup network_pdu
566     mesh_network_setup_pdu(network_pdu, netkey_index, network_key->nid, 1, ttl, 0, src, dest, transport_pdu_data, transport_pdu_len);
567 
568     return 0;
569 }
570 
571 #if 0
572 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,
573                           const uint8_t * control_pdu_data, uint16_t control_pdu_len){
574 
575     if (control_pdu_len > 256) return 1;
576 
577     const mesh_network_key_t * network_key = mesh_network_key_list_get(netkey_index);
578     if (!network_key) return 1;
579 
580     (void)memcpy(transport_pdu->data, control_pdu_data, control_pdu_len);
581     transport_pdu->len = control_pdu_len;
582     transport_pdu->netkey_index = netkey_index;
583     transport_pdu->akf_aid_control = opcode;
584     transport_pdu->transmic_len = 0;    // no TransMIC for control
585     mesh_transport_set_nid_ivi(transport_pdu, network_key->nid);
586     mesh_transport_set_src(transport_pdu, src);
587     mesh_transport_set_dest(transport_pdu, dest);
588     mesh_transport_set_ctl_ttl(transport_pdu, 0x80 | ttl);
589 
590     return 0;
591 }
592 #endif
593 
594 uint8_t mesh_upper_transport_setup_control_pdu(mesh_pdu_t * pdu, uint16_t netkey_index,
595                                                uint8_t ttl, uint16_t src, uint16_t dest, uint8_t opcode, const uint8_t * control_pdu_data, uint16_t control_pdu_len){
596     switch (pdu->pdu_type){
597         case MESH_PDU_TYPE_UPPER_UNSEGMENTED_CONTROL:
598             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);
599         default:
600             btstack_assert(0);
601             return 1;
602     }
603 }
604 
605 static uint8_t mesh_upper_transport_setup_unsegmented_access_pdu_header(mesh_unsegmented_pdu_t * unsegmented_pdu, uint16_t netkey_index,
606                                                                         uint16_t appkey_index, uint8_t ttl, uint16_t src, uint16_t dest){
607 
608     mesh_network_pdu_t * network_pdu = unsegmented_pdu->segment;
609 
610     // get app or device key
611     const mesh_transport_key_t * appkey;
612     appkey = mesh_transport_key_get(appkey_index);
613     if (appkey == NULL){
614         printf("appkey_index %x unknown\n", appkey_index);
615         return 1;
616     }
617     uint8_t akf_aid = (appkey->akf << 6) | appkey->aid;
618 
619     // lookup network by netkey_index
620     const mesh_network_key_t * network_key = mesh_network_key_list_get(netkey_index);
621     if (!network_key) return 1;
622 
623     unsegmented_pdu->appkey_index = appkey_index;
624 
625     network_pdu->data[9] = akf_aid;
626     // setup network_pdu
627     mesh_network_setup_pdu_header(network_pdu, netkey_index, network_key->nid, 0, ttl, 0, src, dest);
628     return 0;
629 }
630 
631 static uint8_t mesh_upper_transport_setup_segmented_access_pdu_header(mesh_access_pdu_t * access_pdu, uint16_t netkey_index,
632     uint16_t appkey_index, uint8_t ttl, uint16_t src, uint16_t dest, uint8_t szmic){
633 
634     // get app or device key
635     const mesh_transport_key_t *appkey;
636     appkey = mesh_transport_key_get(appkey_index);
637     if (appkey == NULL) {
638         printf("[!] Upper transport, setup segmented Access PDU - appkey_index %x unknown\n", appkey_index);
639         return 1;
640     }
641     uint8_t akf_aid = (appkey->akf << 6) | appkey->aid;
642 
643     // lookup network by netkey_index
644     const mesh_network_key_t *network_key = mesh_network_key_list_get(netkey_index);
645     if (!network_key) return 1;
646     if (network_key == NULL) {
647         printf("[!] Upper transport, setup segmented Access PDU - netkey_index %x unknown\n", appkey_index);
648         return 1;
649     }
650 
651     const uint8_t trans_mic_len = szmic ? 8 : 4;
652 
653     // store in transport pdu
654     access_pdu->transmic_len = trans_mic_len;
655     access_pdu->netkey_index = netkey_index;
656     access_pdu->appkey_index = appkey_index;
657     access_pdu->akf_aid_control = akf_aid;
658     mesh_access_set_nid_ivi(access_pdu, network_key->nid | ((mesh_get_iv_index_for_tx() & 1) << 7));
659     mesh_access_set_src(access_pdu, src);
660     mesh_access_set_dest(access_pdu, dest);
661     mesh_access_set_ctl_ttl(access_pdu, ttl);
662     return 0;
663 }
664 
665 static uint8_t mesh_upper_transport_setup_upper_access_pdu_header(mesh_upper_transport_pdu_t * upper_pdu, uint16_t netkey_index,
666                                                                   uint16_t appkey_index, uint8_t ttl, uint16_t src, uint16_t dest, uint8_t szmic){
667 
668     // get app or device key
669     const mesh_transport_key_t *appkey;
670     appkey = mesh_transport_key_get(appkey_index);
671     if (appkey == NULL) {
672         printf("[!] Upper transport, setup segmented Access PDU - appkey_index %x unknown\n", appkey_index);
673         return 1;
674     }
675     uint8_t akf_aid = (appkey->akf << 6) | appkey->aid;
676 
677     // lookup network by netkey_index
678     const mesh_network_key_t *network_key = mesh_network_key_list_get(netkey_index);
679     if (!network_key) return 1;
680     if (network_key == NULL) {
681         printf("[!] Upper transport, setup segmented Access PDU - netkey_index %x unknown\n", appkey_index);
682         return 1;
683     }
684 
685     const uint8_t trans_mic_len = szmic ? 8 : 4;
686 
687     // store in transport pdu
688     upper_pdu->ivi_nid = network_key->nid | ((mesh_get_iv_index_for_tx() & 1) << 7);
689     upper_pdu->ctl_ttl = ttl;
690     upper_pdu->src = src;
691     upper_pdu->dst = dest;
692     upper_pdu->transmic_len = trans_mic_len;
693     upper_pdu->netkey_index = netkey_index;
694     upper_pdu->appkey_index = appkey_index;
695     upper_pdu->akf_aid_control = akf_aid;
696     return 0;
697 }
698 
699 static uint8_t mesh_upper_transport_setup_upper_access_pdu(mesh_upper_transport_pdu_t * upper_pdu, uint16_t netkey_index, uint16_t appkey_index, uint8_t ttl, uint16_t src, uint16_t dest,
700                                                            uint8_t szmic, const uint8_t * access_pdu_data, uint8_t access_pdu_len){
701     int status = mesh_upper_transport_setup_upper_access_pdu_header(upper_pdu, netkey_index, appkey_index, ttl, src,
702                                                                     dest, szmic);
703     if (status) return status;
704 
705     // store in transport pdu
706     uint16_t offset = 0;
707     mesh_segmented_append_payload(access_pdu_data, access_pdu_len, &upper_pdu->segments);
708     upper_pdu->len = access_pdu_len;
709     return 0;
710 }
711 
712 
713 uint8_t mesh_upper_transport_setup_access_pdu_header(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     switch (pdu->pdu_type){
716         case MESH_PDU_TYPE_ACCESS:
717             return mesh_upper_transport_setup_segmented_access_pdu_header((mesh_access_pdu_t *) pdu, netkey_index, appkey_index, ttl, src, dest, szmic);
718         case MESH_PDU_TYPE_UNSEGMENTED:
719             return mesh_upper_transport_setup_unsegmented_access_pdu_header((mesh_unsegmented_pdu_t *) pdu, netkey_index, appkey_index, ttl, src, dest);
720         default:
721             btstack_assert(false);
722             return 1;
723     }
724 }
725 
726 uint8_t mesh_upper_transport_setup_access_pdu(mesh_pdu_t * pdu, uint16_t netkey_index, uint16_t appkey_index,
727                                               uint8_t ttl, uint16_t src, uint16_t dest, uint8_t szmic,
728                                               const uint8_t * access_pdu_data, uint8_t access_pdu_len){
729     switch (pdu->pdu_type){
730         case MESH_PDU_TYPE_UPPER_SEGMENTED_ACCESS:
731         case MESH_PDU_TYPE_UPPER_UNSEGMENTED_ACCESS:
732             return mesh_upper_transport_setup_upper_access_pdu((mesh_upper_transport_pdu_t *) pdu, netkey_index,
733                                                                appkey_index, ttl, src, dest, szmic, access_pdu_data,
734                                                                access_pdu_len);
735         default:
736             btstack_assert(false);
737             return 1;
738     }
739 }
740 
741 static mesh_transport_key_t * mesh_upper_transport_get_outgoing_appkey(uint16_t netkey_index, uint16_t appkey_index){
742     // Device Key is fixed
743     if (appkey_index == MESH_DEVICE_KEY_INDEX) {
744         return mesh_transport_key_get(appkey_index);
745     }
746 
747     // Get key refresh state from subnet
748     mesh_subnet_t * subnet = mesh_subnet_get_by_netkey_index(netkey_index);
749     if (subnet == NULL) return NULL;
750 
751     // identify old and new app keys for given appkey_index
752     mesh_transport_key_t * old_key = NULL;
753     mesh_transport_key_t * new_key = NULL;
754     mesh_transport_key_iterator_t it;
755     mesh_transport_key_iterator_init(&it, netkey_index);
756     while (mesh_transport_key_iterator_has_more(&it)){
757         mesh_transport_key_t * transport_key = mesh_transport_key_iterator_get_next(&it);
758         if (transport_key->appkey_index != appkey_index) continue;
759         if (transport_key->old_key == 0) {
760             new_key = transport_key;
761         } else {
762             old_key = transport_key;
763         }
764     }
765 
766     // if no key is marked as old, just use the current one
767     if (old_key == NULL) return new_key;
768 
769     // use new key if it exists in phase two
770     if ((subnet->key_refresh == MESH_KEY_REFRESH_SECOND_PHASE) && (new_key != NULL)){
771         return new_key;
772     } else {
773         return old_key;
774     }
775 }
776 
777 static void mesh_upper_transport_send_upper_segmented_pdu(mesh_upper_transport_pdu_t * upper_pdu){
778 
779     // TODO: store upper pdu in outgoing pdus active or similar
780     outgoing_upper_transport_pdu = upper_pdu;
781 
782     mesh_segmented_pdu_t * message_pdu   = &outgoing_segmented_message_singleton;
783     message_pdu->pdu_header.pdu_type = MESH_PDU_TYPE_SEGMENTED;
784 
785     // convert mesh_access_pdu_t into mesh_segmented_pdu_t
786     mesh_segmented_append_payload(crypto_buffer, upper_pdu->len, &message_pdu->segments);
787 
788     // copy meta
789     message_pdu->len = upper_pdu->len;
790     message_pdu->netkey_index = upper_pdu->netkey_index;
791     message_pdu->transmic_len = upper_pdu->transmic_len;
792     message_pdu->akf_aid_control = upper_pdu->akf_aid_control;
793     message_pdu->flags = upper_pdu->flags;
794 
795     // setup message_pdu header
796     // (void)memcpy(message_pdu->network_header, upper_pdu->network_header, 9);
797     // TODO: use fields in mesh_segmented_pdu_t and setup network header in lower transport
798     message_pdu->network_header[0] = upper_pdu->ivi_nid;
799     message_pdu->network_header[1] = upper_pdu->ctl_ttl;
800     big_endian_store_24(message_pdu->network_header, 2, upper_pdu->seq);
801     big_endian_store_16(message_pdu->network_header, 5, upper_pdu->src);
802     big_endian_store_16(message_pdu->network_header, 7, upper_pdu->dst);
803 
804     mesh_lower_transport_send_pdu((mesh_pdu_t*) message_pdu);
805 }
806 
807 static void mesh_upper_transport_send_upper_unsegmented_pdu(mesh_upper_transport_pdu_t * upper_pdu){
808 
809     // TODO: store upper pdu in outgoing pdus active or similar
810     outgoing_upper_transport_pdu = upper_pdu;
811 
812     mesh_unsegmented_pdu_t * unsegmented_pdu   = &outgoing_unsegmented_pdu_singleton;
813     unsegmented_pdu->pdu_header.pdu_type = MESH_PDU_TYPE_UNSEGMENTED;
814 
815     // provide segment
816     mesh_network_pdu_t * network_pdu = mesh_network_pdu_get();
817     btstack_assert(network_pdu);
818     unsegmented_pdu->segment = network_pdu;
819 
820     // setup network pdu
821     network_pdu->data[0] = upper_pdu->ivi_nid;
822     network_pdu->data[1] = upper_pdu->ctl_ttl;
823     big_endian_store_24(network_pdu->data, 2, upper_pdu->seq);
824     big_endian_store_16(network_pdu->data, 5, upper_pdu->src);
825     big_endian_store_16(network_pdu->data, 7, upper_pdu->dst);
826     network_pdu->netkey_index = upper_pdu->netkey_index;
827 
828     // setup acess message
829     network_pdu->data[9] = upper_pdu->akf_aid_control;
830     btstack_assert(upper_pdu->len < 15);
831     (void)memcpy(&network_pdu->data[10], crypto_buffer, upper_pdu->len);
832     network_pdu->len = 10 + upper_pdu->len;
833     network_pdu->flags = 0;
834 
835     mesh_lower_transport_send_pdu((mesh_pdu_t*) unsegmented_pdu);
836 }
837 
838 static void mesh_upper_transport_send_upper_access_pdu_ccm(void * arg){
839     crypto_active = 0;
840 
841     mesh_upper_transport_pdu_t * upper_pdu = (mesh_upper_transport_pdu_t *) arg;
842     mesh_print_hex("EncAccessPayload", crypto_buffer, upper_pdu->len);
843     // store TransMIC
844     btstack_crypto_ccm_get_authentication_value(&ccm, &crypto_buffer[upper_pdu->len]);
845     mesh_print_hex("TransMIC", &crypto_buffer[upper_pdu->len], upper_pdu->transmic_len);
846     upper_pdu->len += upper_pdu->transmic_len;
847     mesh_print_hex("UpperTransportPDU", crypto_buffer, upper_pdu->len);
848     switch (upper_pdu->pdu_header.pdu_type){
849         case MESH_PDU_TYPE_UPPER_UNSEGMENTED_ACCESS:
850             mesh_upper_transport_send_upper_unsegmented_pdu(upper_pdu);
851             break;
852         case MESH_PDU_TYPE_UPPER_SEGMENTED_ACCESS:
853             mesh_upper_transport_send_upper_segmented_pdu(upper_pdu);
854             break;
855         default:
856             btstack_assert(false);
857     }
858 }
859 
860 static void mesh_upper_transport_send_upper_access_pdu_digest(void *arg){
861     mesh_upper_transport_pdu_t * upper_pdu = (mesh_upper_transport_pdu_t *) arg;
862     uint16_t  access_pdu_len  = upper_pdu->len;
863     btstack_crypto_ccm_encrypt_block(&ccm, access_pdu_len, crypto_buffer, crypto_buffer,
864                                      &mesh_upper_transport_send_upper_access_pdu_ccm, upper_pdu);
865 }
866 
867 static void mesh_upper_transport_send_upper_access_pdu(mesh_upper_transport_pdu_t * upper_pdu){
868 
869     // if dst is virtual address, lookup label uuid and hash
870     uint16_t aad_len = 0;
871     mesh_virtual_address_t * virtual_address = NULL;
872     if (mesh_network_address_virtual(upper_pdu->dst)){
873         virtual_address = mesh_virtual_address_for_pseudo_dst(upper_pdu->dst);
874         if (!virtual_address){
875             printf("No virtual address register for pseudo dst %4x\n", upper_pdu->dst);
876             mesh_access_message_handler(MESH_TRANSPORT_PDU_SENT, MESH_TRANSPORT_STATUS_SEND_FAILED, (mesh_pdu_t *) upper_pdu);
877             return;
878         }
879         // printf("Using hash %4x with LabelUUID: ", virtual_address->hash);
880         // printf_hexdump(virtual_address->label_uuid, 16);
881         aad_len = 16;
882         upper_pdu->dst = virtual_address->hash;
883     }
884 
885     // get app or device key
886     uint16_t appkey_index = upper_pdu->appkey_index;
887     const mesh_transport_key_t * appkey = mesh_upper_transport_get_outgoing_appkey(upper_pdu->netkey_index, appkey_index);
888     if (appkey == NULL){
889         printf("AppKey %04x not found, drop message\n", appkey_index);
890         mesh_access_message_handler(MESH_TRANSPORT_PDU_SENT, MESH_TRANSPORT_STATUS_SEND_FAILED, (mesh_pdu_t *) upper_pdu);
891         return;
892     }
893 
894     // reserve slot
895     mesh_lower_transport_reserve_slot();
896 
897     // reserve one sequence number, which is also used to encrypt access payload
898     uint32_t seq = mesh_sequence_number_next();
899     upper_pdu->flags |= MESH_TRANSPORT_FLAG_SEQ_RESERVED;
900     upper_pdu->seq = seq;
901 
902     // also reserves crypto_buffer
903     crypto_active = 1;
904 
905     // flatten segmented pdu into crypto buffer
906     uint16_t payload_len = mesh_upper_pdu_flatten(upper_pdu, crypto_buffer, sizeof(crypto_buffer));
907     btstack_assert(payload_len == upper_pdu->len);
908 
909     // Dump PDU
910     printf("[+] Upper transport, send upper (un)segmented Access PDU - dest %04x, seq %06x\n", upper_pdu->dst, upper_pdu->seq);
911     mesh_print_hex("Access Payload", crypto_buffer, upper_pdu->len);
912 
913     // setup nonce - uses dst, so after pseudo address translation
914     if (appkey_index == MESH_DEVICE_KEY_INDEX){
915         transport_segmented_setup_device_nonce(application_nonce, (mesh_pdu_t *) upper_pdu);
916     } else {
917         transport_segmented_setup_application_nonce(application_nonce, (mesh_pdu_t *) upper_pdu);
918     }
919 
920     // Dump key
921     mesh_print_hex("AppOrDevKey", appkey->key, 16);
922 
923     // encrypt ccm
924     uint8_t   transmic_len    = upper_pdu->transmic_len;
925     uint16_t  access_pdu_len  = upper_pdu->len;
926     btstack_crypto_ccm_init(&ccm, appkey->key, application_nonce, access_pdu_len, aad_len, transmic_len);
927     if (virtual_address){
928         mesh_print_hex("LabelUUID", virtual_address->label_uuid, 16);
929         btstack_crypto_ccm_digest(&ccm, virtual_address->label_uuid, 16,
930                                   &mesh_upper_transport_send_upper_access_pdu_digest, upper_pdu);
931     } else {
932         mesh_upper_transport_send_upper_access_pdu_digest(upper_pdu);
933     }
934 }
935 
936 static void mesh_upper_transport_send_unsegmented_control_pdu(mesh_network_pdu_t * network_pdu){
937     // reserve slot
938     mesh_lower_transport_reserve_slot();
939     // reserve sequence number
940     uint32_t seq = mesh_sequence_number_next();
941     mesh_network_pdu_set_seq(network_pdu, seq);
942     // Dump PDU
943     uint8_t opcode = network_pdu->data[9];
944     printf("[+] Upper transport, send unsegmented Control PDU %p - seq %06x opcode %02x\n", network_pdu, seq, opcode);
945     mesh_print_hex("Access Payload", &network_pdu->data[10], network_pdu->len - 10);
946     // wrap into mesh-unsegmented-pdu
947     outgoing_unsegmented_pdu_singleton.pdu_header.pdu_type = MESH_PDU_TYPE_UNSEGMENTED;
948     outgoing_unsegmented_pdu_singleton.segment = network_pdu;
949     outgoing_unsegmented_pdu_singleton.flags = MESH_TRANSPORT_FLAG_CONTROL;
950 
951     // send
952      mesh_lower_transport_send_pdu((mesh_pdu_t *) &outgoing_unsegmented_pdu_singleton);
953 }
954 
955 #if 0
956 static void mesh_upper_transport_send_segmented_control_pdu(mesh_transport_pdu_t * transport_pdu){
957     // reserve slot
958     mesh_lower_transport_reserve_slot();
959     // reserve sequence number
960     uint32_t seq = mesh_sequence_number_next();
961     transport_pdu->flags |= MESH_TRANSPORT_FLAG_SEQ_RESERVED;
962     mesh_transport_set_seq(transport_pdu, seq);
963     // Dump PDU
964     uint8_t opcode = transport_pdu->data[0];
965     printf("[+] Upper transport, send segmented Control PDU %p - seq %06x opcode %02x\n", transport_pdu, seq, opcode);
966     mesh_print_hex("Access Payload", &transport_pdu->data[1], transport_pdu->len - 1);
967     // send
968     btstack_assert(false);
969     // mesh_upper_transport_send_segmented_pdu(transport_pdu);
970 }
971 #endif
972 
973 static void mesh_upper_transport_run(void){
974 
975     while(!btstack_linked_list_empty(&upper_transport_incoming)){
976 
977         if (crypto_active) return;
978 
979         // get next message
980         mesh_pdu_t * pdu =  (mesh_pdu_t *) btstack_linked_list_pop(&upper_transport_incoming);
981         mesh_network_pdu_t   * network_pdu;
982         mesh_segmented_pdu_t   * message_pdu;
983         mesh_unsegmented_pdu_t * unsegmented_pdu;
984         switch (pdu->pdu_type){
985             case MESH_PDU_TYPE_UNSEGMENTED:
986                 unsegmented_pdu = (mesh_unsegmented_pdu_t *) pdu;
987                 network_pdu = unsegmented_pdu->segment;
988                 btstack_assert(network_pdu != NULL);
989                 // control?
990                 if (mesh_network_control(network_pdu)) {
991 
992                     incoming_control_pdu =  &incoming_control_pdu_singleton;
993                     incoming_control_pdu->pdu_header.pdu_type = MESH_PDU_TYPE_CONTROL;
994                     incoming_control_pdu->len =  network_pdu->len;
995                     incoming_control_pdu->netkey_index =  network_pdu->netkey_index;
996 
997                     uint8_t * lower_transport_pdu = mesh_network_pdu_data(network_pdu);
998 
999                     incoming_control_pdu->akf_aid_control = lower_transport_pdu[0];
1000                     incoming_control_pdu->len = network_pdu->len - 10; // 9 header + 1 opcode
1001                     (void)memcpy(incoming_control_pdu->data, &lower_transport_pdu[1], incoming_control_pdu->len);
1002 
1003                     // copy meta data into encrypted pdu buffer
1004                     (void)memcpy(incoming_control_pdu->network_header, network_pdu->data, 9);
1005 
1006                     mesh_print_hex("Assembled payload", incoming_control_pdu->data, incoming_control_pdu->len);
1007 
1008                     // free mesh message
1009                     mesh_lower_transport_message_processed_by_higher_layer(pdu);
1010 
1011                     btstack_assert(mesh_control_message_handler != NULL);
1012                     mesh_pdu_t * pdu = (mesh_pdu_t*) incoming_control_pdu;
1013                     mesh_control_message_handler(MESH_TRANSPORT_PDU_RECEIVED, MESH_TRANSPORT_STATUS_SUCCESS, pdu);
1014 
1015                 } else {
1016 
1017                     incoming_access_pdu_encrypted = &incoming_access_pdu_encrypted_singleton;
1018                     incoming_access_pdu_encrypted->pdu_header.pdu_type = MESH_PDU_TYPE_ACCESS;
1019                     incoming_access_pdu_decrypted = &incoming_access_pdu_decrypted_singleton;
1020 
1021                     incoming_access_pdu_encrypted->netkey_index = network_pdu->netkey_index;
1022                     incoming_access_pdu_encrypted->transmic_len = 4;
1023 
1024                     uint8_t * lower_transport_pdu = mesh_network_pdu_data(network_pdu);
1025 
1026                     incoming_access_pdu_encrypted->akf_aid_control = lower_transport_pdu[0];
1027                     incoming_access_pdu_encrypted->len = network_pdu->len - 10; // 9 header + 1 AID
1028                     (void)memcpy(incoming_access_pdu_encrypted->data, &lower_transport_pdu[1], incoming_access_pdu_encrypted->len);
1029 
1030                     // copy meta data into encrypted pdu buffer
1031                     (void)memcpy(incoming_access_pdu_encrypted->network_header, network_pdu->data, 9);
1032 
1033                     mesh_print_hex("Assembled payload", incoming_access_pdu_encrypted->data, incoming_access_pdu_encrypted->len);
1034 
1035                     // free mesh message
1036                     mesh_lower_transport_message_processed_by_higher_layer(pdu);
1037 
1038                     // get encoded transport pdu and start processing
1039                     mesh_upper_transport_process_segmented_message();
1040                 }
1041                 break;
1042             case MESH_PDU_TYPE_SEGMENTED:
1043                 message_pdu = (mesh_segmented_pdu_t *) pdu;
1044                 uint8_t ctl = mesh_message_ctl(message_pdu);
1045                 if (ctl){
1046                     incoming_control_pdu=  &incoming_control_pdu_singleton;
1047                     incoming_control_pdu->pdu_header.pdu_type = MESH_PDU_TYPE_CONTROL;
1048 
1049                     // flatten
1050                     mesh_segmented_pdu_flatten(&message_pdu->segments, 8, incoming_control_pdu->data);
1051 
1052                     // copy meta data into encrypted pdu buffer
1053                     incoming_control_pdu->len =  message_pdu->len;
1054                     incoming_control_pdu->netkey_index =  message_pdu->netkey_index;
1055                     incoming_control_pdu->akf_aid_control =  message_pdu->akf_aid_control;
1056                     incoming_control_pdu->flags = 0;
1057                     (void)memcpy(incoming_control_pdu->network_header, message_pdu->network_header, 9);
1058 
1059                     mesh_print_hex("Assembled payload", incoming_control_pdu->data, incoming_control_pdu->len);
1060 
1061                     // free mesh message
1062                     mesh_lower_transport_message_processed_by_higher_layer((mesh_pdu_t *)message_pdu);
1063 
1064                     btstack_assert(mesh_control_message_handler != NULL);
1065                     mesh_pdu_t * pdu = (mesh_pdu_t*) incoming_control_pdu;
1066                     mesh_access_message_handler(MESH_TRANSPORT_PDU_RECEIVED, MESH_TRANSPORT_STATUS_SUCCESS, pdu);
1067 
1068                 } else {
1069 
1070                     incoming_access_pdu_encrypted = &incoming_access_pdu_encrypted_singleton;
1071                     incoming_access_pdu_encrypted->pdu_header.pdu_type = MESH_PDU_TYPE_ACCESS;
1072                     incoming_access_pdu_decrypted = &incoming_access_pdu_decrypted_singleton;
1073 
1074                     // flatten
1075                     mesh_segmented_pdu_flatten(&message_pdu->segments, 12, incoming_access_pdu_encrypted->data);
1076 
1077                     // copy meta data into encrypted pdu buffer
1078                     incoming_access_pdu_encrypted->len =  message_pdu->len;
1079                     incoming_access_pdu_encrypted->netkey_index =  message_pdu->netkey_index;
1080                     incoming_access_pdu_encrypted->transmic_len =  message_pdu->transmic_len;
1081                     incoming_access_pdu_encrypted->akf_aid_control =  message_pdu->akf_aid_control;
1082                     (void)memcpy(incoming_access_pdu_encrypted->network_header, message_pdu->network_header, 9);
1083 
1084                     mesh_print_hex("Assembled payload", incoming_access_pdu_encrypted->data, incoming_access_pdu_encrypted->len);
1085 
1086                     // free mesh message
1087                     mesh_lower_transport_message_processed_by_higher_layer((mesh_pdu_t *)message_pdu);
1088 
1089                     // get encoded transport pdu and start processing
1090                     mesh_upper_transport_process_segmented_message();
1091                 }
1092                 break;
1093             default:
1094                 btstack_assert(0);
1095                 break;
1096         }
1097     }
1098 
1099     while (!btstack_linked_list_empty(&upper_transport_outgoing)){
1100 
1101         if (crypto_active) break;
1102 
1103         if (outgoing_segmented_access_pdu != NULL) break;
1104 
1105         mesh_pdu_t * pdu =  (mesh_pdu_t *) btstack_linked_list_get_first_item(&upper_transport_outgoing);
1106         if (mesh_lower_transport_can_send_to_dest(mesh_pdu_dst(pdu)) == 0) break;
1107 
1108         (void) btstack_linked_list_pop(&upper_transport_outgoing);
1109 
1110         mesh_unsegmented_pdu_t * unsegmented_pdu;
1111 
1112         switch (pdu->pdu_type){
1113             case MESH_PDU_TYPE_UPPER_UNSEGMENTED_CONTROL:
1114                 btstack_assert(mesh_pdu_ctl(pdu) != 0);
1115                 mesh_upper_transport_send_unsegmented_control_pdu((mesh_network_pdu_t *) pdu);
1116                 break;
1117             case MESH_PDU_TYPE_UPPER_SEGMENTED_ACCESS:
1118             case MESH_PDU_TYPE_UPPER_UNSEGMENTED_ACCESS:
1119                 mesh_upper_transport_send_upper_access_pdu((mesh_upper_transport_pdu_t *) pdu);
1120                 break;
1121             default:
1122                 btstack_assert(false);
1123                 break;
1124         }
1125     }
1126 }
1127 
1128 
1129 
1130 static void mesh_upper_transport_pdu_handler(mesh_transport_callback_type_t callback_type, mesh_transport_status_t status, mesh_pdu_t * pdu){
1131     mesh_pdu_t * pdu_to_report;
1132     mesh_unsegmented_pdu_t * unsegmented_pdu;
1133     switch (callback_type){
1134         case MESH_TRANSPORT_PDU_RECEIVED:
1135             mesh_upper_transport_message_received(pdu);
1136             break;
1137         case MESH_TRANSPORT_PDU_SENT:
1138             switch (pdu->pdu_type){
1139                 case MESH_PDU_TYPE_SEGMENTED:
1140                     // free chunks
1141                     while (!btstack_linked_list_empty(&outgoing_segmented_message_singleton.segments)){
1142                         mesh_network_pdu_t * network_pdu = (mesh_network_pdu_t *) btstack_linked_list_pop(&outgoing_segmented_message_singleton.segments);
1143                         mesh_network_pdu_free(network_pdu);
1144                     }
1145                     // notify upper layer but use transport pdu
1146                     pdu_to_report = (mesh_pdu_t *) outgoing_segmented_access_pdu;
1147                     outgoing_segmented_access_pdu = NULL;
1148                     if (mesh_pdu_ctl(pdu_to_report)){
1149                         mesh_control_message_handler(callback_type, status, pdu_to_report);
1150                     } else {
1151                         mesh_access_message_handler(callback_type, status, pdu_to_report);
1152                     }
1153                     break;
1154                 case MESH_PDU_TYPE_UNSEGMENTED:
1155                     unsegmented_pdu = (mesh_unsegmented_pdu_t *) pdu;
1156                     if (unsegmented_pdu == &outgoing_unsegmented_pdu_singleton){
1157                         if ((unsegmented_pdu->flags & MESH_TRANSPORT_FLAG_CONTROL) == 0){
1158                             // notify upper layer but use network pdu (control pdu)
1159                             mesh_network_pdu_t * network_pdu = outgoing_unsegmented_pdu_singleton.segment;
1160                             outgoing_unsegmented_pdu_singleton.segment = NULL;
1161                             mesh_control_message_handler(callback_type, status, (mesh_pdu_t *) network_pdu);
1162                         } else {
1163                             // notify upper layer but use upper access pdu
1164                             mesh_network_pdu_t * network_pdu = outgoing_unsegmented_pdu_singleton.segment;
1165                             outgoing_unsegmented_pdu_singleton.segment = NULL;
1166                             mesh_network_pdu_free(network_pdu);
1167                             pdu_to_report = (mesh_pdu_t *) outgoing_upper_transport_pdu;
1168                             mesh_access_message_handler(callback_type, status, pdu_to_report);
1169                         }
1170                     } else {
1171                         btstack_assert((unsegmented_pdu->flags & MESH_TRANSPORT_FLAG_CONTROL) == 0);
1172                         mesh_access_message_handler(callback_type, status, pdu);
1173                     }
1174                     break;
1175                 default:
1176                     btstack_assert(false);
1177                     break;
1178             }
1179             mesh_upper_transport_run();
1180             break;
1181         default:
1182             break;
1183     }
1184 }
1185 
1186 void mesh_upper_transport_pdu_free(mesh_pdu_t * pdu){
1187     mesh_network_pdu_t   * network_pdu;
1188     mesh_segmented_pdu_t   * message_pdu;
1189     switch (pdu->pdu_type) {
1190         case MESH_PDU_TYPE_NETWORK:
1191             network_pdu = (mesh_network_pdu_t *) pdu;
1192             mesh_network_pdu_free(network_pdu);
1193             break;
1194         case MESH_PDU_TYPE_SEGMENTED:
1195             message_pdu = (mesh_segmented_pdu_t *) pdu;
1196             mesh_message_pdu_free(message_pdu);
1197         default:
1198             btstack_assert(false);
1199             break;
1200     }
1201 }
1202 
1203 void mesh_upper_transport_message_processed_by_higher_layer(mesh_pdu_t * pdu){
1204     crypto_active = 0;
1205     switch (pdu->pdu_type){
1206         case MESH_PDU_TYPE_ACCESS:
1207             mesh_upper_transport_process_access_message_done((mesh_access_pdu_t *) pdu);
1208         case MESH_PDU_TYPE_CONTROL:
1209             mesh_upper_transport_process_control_message_done((mesh_control_pdu_t *) pdu);
1210             break;
1211         default:
1212             btstack_assert(0);
1213             break;
1214     }
1215 }
1216 
1217 void mesh_upper_transport_register_access_message_handler(void (*callback)(mesh_transport_callback_type_t callback_type, mesh_transport_status_t status, mesh_pdu_t * pdu)) {
1218     mesh_access_message_handler = callback;
1219 }
1220 
1221 void mesh_upper_transport_register_control_message_handler(void (*callback)(mesh_transport_callback_type_t callback_type, mesh_transport_status_t status, mesh_pdu_t * pdu)){
1222     mesh_control_message_handler = callback;
1223 }
1224 
1225 void mesh_upper_transport_init(){
1226     mesh_lower_transport_set_higher_layer_handler(&mesh_upper_transport_pdu_handler);
1227 }
1228