xref: /btstack/src/mesh/mesh_upper_transport.c (revision 242605fa4fdd5052deb372011eeed60056b08b4c)
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;
96 
97 static uint8_t application_nonce[13];
98 static btstack_crypto_ccm_t ccm;
99 static uint8_t crypto_buffer[MESH_ACCESS_PAYLOAD_MAX];
100 static mesh_transport_key_and_virtual_address_iterator_t mesh_transport_key_it;
101 
102 // upper transport callbacks - in access layer
103 static void (*mesh_access_message_handler)( mesh_transport_callback_type_t callback_type, mesh_transport_status_t status, mesh_pdu_t * pdu);
104 static void (*mesh_control_message_handler)( mesh_transport_callback_type_t callback_type, mesh_transport_status_t status, mesh_pdu_t * pdu);
105 
106 // incoming unsegmented (network) and segmented (transport) control and access messages
107 static btstack_linked_list_t upper_transport_incoming;
108 
109 // outgoing unsegmented (network) and segmented (uppert_transport_outgoing) control and access messages
110 static btstack_linked_list_t upper_transport_outgoing;
111 
112 
113 // TODO: higher layer define used for assert
114 #define MESH_ACCESS_OPCODE_NOT_SET 0xFFFFFFFEu
115 
116 void mesh_upper_transport_send_access_pdu(mesh_pdu_t *pdu){
117     switch (pdu->pdu_type){
118         case MESH_PDU_TYPE_UNSEGMENTED:
119         case MESH_PDU_TYPE_ACCESS:
120         case MESH_PDU_TYPE_UPPER_SEGMENTED_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     if (pdu->pdu_type == MESH_PDU_TYPE_NETWORK){
133         btstack_assert( ((mesh_network_pdu_t *) pdu)->len >= 9);
134     }
135 
136     btstack_linked_list_add_tail(&upper_transport_outgoing, (btstack_linked_item_t*) pdu);
137     mesh_upper_transport_run();
138 }
139 
140 static void mesh_print_hex(const char * name, const uint8_t * data, uint16_t len){
141     printf("%-20s ", name);
142     printf_hexdump(data, len);
143 }
144 // static void mesh_print_x(const char * name, uint32_t value){
145 //     printf("%20s: 0x%x", name, (int) value);
146 // }
147 
148 static void mesh_transport_key_and_virtual_address_iterator_init(mesh_transport_key_and_virtual_address_iterator_t *it,
149                                                                  uint16_t dst, uint16_t netkey_index, uint8_t akf,
150                                                                  uint8_t aid) {
151     printf("KEY_INIT: dst %04x, akf %x, aid %x\n", dst, akf, aid);
152     // config
153     it->dst   = dst;
154     // init elements
155     it->key     = NULL;
156     it->address = NULL;
157     // init element iterators
158     mesh_transport_key_aid_iterator_init(&it->key_it, netkey_index, akf, aid);
159     // init address iterator
160     if (mesh_network_address_virtual(it->dst)){
161         mesh_virtual_address_iterator_init(&it->address_it, dst);
162         // get first key
163         if (mesh_transport_key_aid_iterator_has_more(&it->key_it)) {
164             it->key = mesh_transport_key_aid_iterator_get_next(&it->key_it);
165         }
166     }
167 }
168 
169 // cartesian product: keys x addressses
170 static int mesh_transport_key_and_virtual_address_iterator_has_more(mesh_transport_key_and_virtual_address_iterator_t * it){
171     if (mesh_network_address_virtual(it->dst)) {
172         // find next valid entry
173         while (true){
174             if (mesh_virtual_address_iterator_has_more(&it->address_it)) return 1;
175             if (!mesh_transport_key_aid_iterator_has_more(&it->key_it)) return 0;
176             // get next key
177             it->key = mesh_transport_key_aid_iterator_get_next(&it->key_it);
178             mesh_virtual_address_iterator_init(&it->address_it, it->dst);
179         }
180     } else {
181         return mesh_transport_key_aid_iterator_has_more(&it->key_it);
182     }
183 }
184 
185 static void mesh_transport_key_and_virtual_address_iterator_next(mesh_transport_key_and_virtual_address_iterator_t * it){
186     if (mesh_network_address_virtual(it->dst)) {
187         it->address = mesh_virtual_address_iterator_get_next(&it->address_it);
188     } else {
189         it->key = mesh_transport_key_aid_iterator_get_next(&it->key_it);
190     }
191 }
192 
193 // UPPER TRANSPORT
194 
195 uint16_t mesh_access_dst(mesh_access_pdu_t * access_pdu){
196     return big_endian_read_16(access_pdu->network_header, 7);
197 }
198 
199 uint16_t mesh_access_ctl(mesh_access_pdu_t * access_pdu){
200     return access_pdu->network_header[1] >> 7;
201 }
202 
203 uint32_t mesh_access_seq(mesh_access_pdu_t * access_pdu){
204     return big_endian_read_24(access_pdu->network_header, 2);
205 }
206 
207 void mesh_access_set_nid_ivi(mesh_access_pdu_t * access_pdu, uint8_t nid_ivi){
208     access_pdu->network_header[0] = nid_ivi;
209 }
210 void mesh_access_set_ctl_ttl(mesh_access_pdu_t * access_pdu, uint8_t ctl_ttl){
211     access_pdu->network_header[1] = ctl_ttl;
212 }
213 void mesh_access_set_seq(mesh_access_pdu_t * access_pdu, uint32_t seq){
214     big_endian_store_24(access_pdu->network_header, 2, seq);
215 }
216 void mesh_access_set_src(mesh_access_pdu_t * access_pdu, uint16_t src){
217     big_endian_store_16(access_pdu->network_header, 5, src);
218 }
219 void mesh_access_set_dest(mesh_access_pdu_t * access_pdu, uint16_t dest){
220     big_endian_store_16(access_pdu->network_header, 7, dest);
221 }
222 
223 static void mesh_segmented_pdu_flatten(btstack_linked_list_t * segments, uint8_t segment_len, uint8_t * buffer) {
224     // assemble payload
225     btstack_linked_list_iterator_t it;
226     btstack_linked_list_iterator_init(&it, segments);
227     while (btstack_linked_list_iterator_has_next(&it)) {
228         mesh_network_pdu_t *segment = (mesh_network_pdu_t *) btstack_linked_list_iterator_next(&it);
229         btstack_assert(segment->pdu_header.pdu_type == MESH_PDU_TYPE_NETWORK);
230         // get segment n
231         uint8_t *lower_transport_pdu = mesh_network_pdu_data(segment);
232         uint8_t seg_o = (big_endian_read_16(lower_transport_pdu, 2) >> 5) & 0x001f;
233         uint8_t *segment_data = &lower_transport_pdu[4];
234         (void) memcpy(&buffer[seg_o * segment_len], segment_data, segment_len);
235     }
236 }
237 
238 static uint16_t mesh_upper_pdu_flatten(mesh_upper_transport_pdu_t * upper_pdu, uint8_t * buffer, uint16_t buffer_len) {
239     // assemble payload
240     btstack_linked_list_iterator_t it;
241     btstack_linked_list_iterator_init(&it, &upper_pdu->payload.segments);
242     uint16_t offset = 0;
243     while (btstack_linked_list_iterator_has_next(&it)) {
244         mesh_network_pdu_t *segment = (mesh_network_pdu_t *) btstack_linked_list_iterator_next(&it);
245         btstack_assert(segment->pdu_header.pdu_type == MESH_PDU_TYPE_NETWORK);
246         btstack_assert((offset + segment->len) <= buffer_len);
247         (void) memcpy(&buffer[offset], segment->data, segment->len);
248         offset += segment->len;
249     }
250     return offset;
251 }
252 
253 static void mesh_segmented_append_payload(const uint8_t * payload, uint16_t payload_len, btstack_linked_list_t * segments){
254     uint16_t payload_offset = 0;
255     uint16_t bytes_current_segment = 0;
256     mesh_network_pdu_t * network_pdu = (mesh_network_pdu_t *) btstack_linked_list_get_last_item(segments);
257     if (network_pdu){
258         bytes_current_segment = MESH_NETWORK_PAYLOAD_MAX - network_pdu->len;
259     }
260     while (payload_offset < payload_len){
261         if (bytes_current_segment == 0){
262             network_pdu = mesh_network_pdu_get();
263             btstack_assert(network_pdu != NULL);
264             btstack_linked_list_add_tail(segments, (btstack_linked_item_t *) network_pdu);
265             bytes_current_segment = MESH_NETWORK_PAYLOAD_MAX;
266         }
267         uint16_t bytes_to_copy = btstack_min(bytes_current_segment, payload_len - payload_offset);
268         (void) memcpy(&network_pdu->data[network_pdu->len], &payload[payload_offset], bytes_to_copy);
269         bytes_current_segment -= bytes_to_copy;
270         network_pdu->len += bytes_to_copy;
271         payload_offset += bytes_to_copy;
272     }
273 }
274 
275 // stub lower transport
276 
277 static void mesh_upper_transport_dump_pdus(const char *name, btstack_linked_list_t *list){
278     printf("List: %s:\n", name);
279     btstack_linked_list_iterator_t it;
280     btstack_linked_list_iterator_init(&it, list);
281     while (btstack_linked_list_iterator_has_next(&it)){
282         mesh_pdu_t * pdu = (mesh_pdu_t*) btstack_linked_list_iterator_next(&it);
283         printf("- %p\n", pdu);
284         // printf_hexdump( mesh_pdu_data(pdu), mesh_pdu_len(pdu));
285     }
286 }
287 
288 static void mesh_upper_transport_reset_pdus(btstack_linked_list_t *list){
289     while (!btstack_linked_list_empty(list)){
290         mesh_upper_transport_pdu_free((mesh_pdu_t *) btstack_linked_list_pop(list));
291     }
292 }
293 
294 void mesh_upper_transport_dump(void){
295     printf("incoming_unsegmented_pdu_raw: %p\n", incoming_unsegmented_pdu_raw);
296     mesh_upper_transport_dump_pdus("upper_transport_incoming", &upper_transport_incoming);
297 }
298 
299 void mesh_upper_transport_reset(void){
300     crypto_active = 0;
301     if (incoming_unsegmented_pdu_raw){
302         mesh_network_pdu_t * network_pdu = incoming_unsegmented_pdu_raw->segment;
303         btstack_assert(network_pdu != NULL);
304         incoming_unsegmented_pdu_raw->segment = NULL;
305         mesh_network_pdu_free(network_pdu);
306         incoming_unsegmented_pdu_raw = NULL;
307     }
308     outgoing_segmented_access_pdu = NULL;
309     mesh_upper_transport_reset_pdus(&upper_transport_incoming);
310 }
311 
312 static uint32_t iv_index_for_ivi_nid(uint8_t ivi_nid){
313     // get IV Index and IVI
314     uint32_t iv_index = mesh_get_iv_index();
315     int ivi = ivi_nid >> 7;
316 
317     // if least significant bit differs, use previous IV Index
318     if ((iv_index & 1 ) ^ ivi){
319         iv_index--;
320     }
321     return iv_index;
322 }
323 
324 static void transport_unsegmented_setup_nonce(uint8_t * nonce, const mesh_network_pdu_t * network_pdu){
325     nonce[1] = 0x00;    // SZMIC if a Segmented Access message or 0 for all other message formats
326     (void)memcpy(&nonce[2], &network_pdu->data[2], 7);
327     big_endian_store_32(nonce, 9, iv_index_for_ivi_nid(network_pdu->data[0]));
328 }
329 
330 static void transport_segmented_setup_nonce(uint8_t * nonce, const mesh_pdu_t * pdu){
331     mesh_access_pdu_t * access_pdu;
332     mesh_upper_transport_pdu_t * upper_pdu;
333     switch (pdu->pdu_type){
334         case MESH_PDU_TYPE_ACCESS:
335             access_pdu = (mesh_access_pdu_t *) pdu;
336             nonce[1] = access_pdu->transmic_len == 8 ? 0x80 : 0x00;
337             (void)memcpy(&nonce[2], &access_pdu->network_header[2], 7);
338             big_endian_store_32(nonce, 9, iv_index_for_ivi_nid(access_pdu->network_header[0]));
339             break;
340         case MESH_PDU_TYPE_UPPER_SEGMENTED_ACCESS:
341             upper_pdu = (mesh_upper_transport_pdu_t *) pdu;
342             nonce[1] = upper_pdu->transmic_len == 8 ? 0x80 : 0x00;
343             // 'network header'
344             big_endian_store_24(nonce, 2, upper_pdu->seq);
345             big_endian_store_16(nonce, 5, upper_pdu->src);
346             big_endian_store_16(nonce, 7, upper_pdu->dst);
347             big_endian_store_32(nonce, 9, iv_index_for_ivi_nid(upper_pdu->ivi_nid));
348             break;
349         default:
350             btstack_assert(0);
351             break;
352     }
353 }
354 
355 static void transport_unsegmented_setup_application_nonce(uint8_t * nonce, const mesh_network_pdu_t * network_pdu){
356     nonce[0] = 0x01;
357     transport_unsegmented_setup_nonce(nonce, network_pdu);
358     mesh_print_hex("AppNonce", nonce, 13);
359 }
360 
361 static void transport_unsegmented_setup_device_nonce(uint8_t * nonce, const mesh_network_pdu_t * network_pdu){
362     nonce[0] = 0x02;
363     transport_unsegmented_setup_nonce(nonce, network_pdu);
364     mesh_print_hex("DeviceNonce", nonce, 13);
365 }
366 
367 static void transport_segmented_setup_application_nonce(uint8_t * nonce, const mesh_pdu_t * pdu){
368     nonce[0] = 0x01;
369     transport_segmented_setup_nonce(nonce, pdu);
370     mesh_print_hex("AppNonce", nonce, 13);
371 }
372 
373 static void transport_segmented_setup_device_nonce(uint8_t * nonce, const mesh_pdu_t * pdu){
374     nonce[0] = 0x02;
375     transport_segmented_setup_nonce(nonce, pdu);
376     mesh_print_hex("DeviceNonce", nonce, 13);
377 }
378 
379 static void mesh_upper_transport_process_message_done(mesh_segmented_pdu_t *message_pdu){
380     crypto_active = 0;
381     btstack_assert(message_pdu == &incoming_message_pdu_singleton);
382     mesh_network_pdu_t * network_pdu = (mesh_network_pdu_t *) btstack_linked_list_pop(&incoming_message_pdu_singleton.segments);
383     if (mesh_network_control(network_pdu)) {
384         btstack_assert(0);
385     } else {
386         btstack_assert(network_pdu != NULL);
387         mesh_network_pdu_free(network_pdu);
388         mesh_pdu_t * pdu = (mesh_pdu_t *) incoming_unsegmented_pdu_raw;
389         incoming_unsegmented_pdu_raw = NULL;
390         mesh_lower_transport_message_processed_by_higher_layer(pdu);
391     }
392     mesh_upper_transport_run();
393 }
394 
395 static void mesh_upper_transport_process_unsegmented_message_done(mesh_pdu_t * pdu){
396     btstack_assert(pdu != NULL);
397     btstack_assert(pdu->pdu_type == MESH_PDU_TYPE_UNSEGMENTED);
398 
399     mesh_unsegmented_pdu_t * unsegmented_incoming_pdu = (mesh_unsegmented_pdu_t *) pdu;
400     btstack_assert(unsegmented_incoming_pdu == incoming_unsegmented_pdu_raw);
401 
402     crypto_active = 0;
403     incoming_unsegmented_pdu_raw = NULL;
404     mesh_network_pdu_t * network_pdu = unsegmented_incoming_pdu->segment;
405     if (!mesh_network_control(network_pdu)) {
406         mesh_network_pdu_free(network_pdu);
407     }
408 
409     mesh_lower_transport_message_processed_by_higher_layer(pdu);
410     mesh_upper_transport_run();
411 }
412 
413 static void mesh_upper_transport_process_access_message_done(mesh_access_pdu_t *access_pdu){
414     crypto_active = 0;
415     btstack_assert(mesh_access_ctl(access_pdu) == 0);
416     incoming_access_pdu_encrypted = NULL;
417     mesh_upper_transport_run();
418 }
419 
420 static void mesh_upper_transport_process_control_message_done(mesh_control_pdu_t * control_pdu){
421     crypto_active = 0;
422     incoming_control_pdu = NULL;
423     mesh_upper_transport_run();
424 }
425 
426 static void mesh_upper_transport_validate_segmented_message_ccm(void * arg){
427     UNUSED(arg);
428 
429     uint8_t * upper_transport_pdu     = incoming_access_pdu_decrypted->data;
430     uint8_t   upper_transport_pdu_len = incoming_access_pdu_decrypted->len - incoming_access_pdu_decrypted->transmic_len;
431 
432     mesh_print_hex("Decrypted PDU", upper_transport_pdu, upper_transport_pdu_len);
433 
434     // store TransMIC
435     uint8_t trans_mic[8];
436     btstack_crypto_ccm_get_authentication_value(&ccm, trans_mic);
437     mesh_print_hex("TransMIC", trans_mic, incoming_access_pdu_decrypted->transmic_len);
438 
439     if (memcmp(trans_mic, &upper_transport_pdu[upper_transport_pdu_len], incoming_access_pdu_decrypted->transmic_len) == 0){
440         printf("TransMIC matches\n");
441 
442         // remove TransMIC from payload
443         incoming_access_pdu_decrypted->len -= incoming_access_pdu_decrypted->transmic_len;
444 
445         // if virtual address, update dst to pseudo_dst
446         if (mesh_network_address_virtual(mesh_access_dst(incoming_access_pdu_decrypted))){
447             big_endian_store_16(incoming_access_pdu_decrypted->network_header, 7, mesh_transport_key_it.address->pseudo_dst);
448         }
449 
450         // pass to upper layer
451         btstack_assert(mesh_access_message_handler != NULL);
452         mesh_pdu_t * pdu = (mesh_pdu_t*) incoming_access_pdu_decrypted;
453         mesh_access_message_handler(MESH_TRANSPORT_PDU_RECEIVED, MESH_TRANSPORT_STATUS_SUCCESS, pdu);
454 
455         printf("\n");
456 
457     } else {
458         uint8_t akf = incoming_access_pdu_decrypted->akf_aid_control & 0x40;
459         if (akf){
460             printf("TransMIC does not match, try next key\n");
461             mesh_upper_transport_validate_segmented_message();
462         } else {
463             printf("TransMIC does not match device key, done\n");
464             // done
465             mesh_upper_transport_process_access_message_done(incoming_access_pdu_decrypted);
466         }
467     }
468 }
469 
470 static void mesh_upper_transport_validate_segmented_message_digest(void * arg){
471     UNUSED(arg);
472     uint8_t   upper_transport_pdu_len      = incoming_access_pdu_encrypted->len - incoming_access_pdu_encrypted->transmic_len;
473     uint8_t * upper_transport_pdu_data_in  = incoming_access_pdu_encrypted->data;
474     uint8_t * upper_transport_pdu_data_out = incoming_access_pdu_decrypted->data;
475     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);
476 }
477 
478 static void mesh_upper_transport_validate_segmented_message(void){
479     uint8_t * upper_transport_pdu_data =  incoming_access_pdu_decrypted->data;
480     uint8_t   upper_transport_pdu_len  = incoming_access_pdu_decrypted->len - incoming_access_pdu_decrypted->transmic_len;
481 
482     if (!mesh_transport_key_and_virtual_address_iterator_has_more(&mesh_transport_key_it)){
483         printf("No valid transport key found\n");
484         mesh_upper_transport_process_access_message_done(incoming_access_pdu_decrypted);
485         return;
486     }
487     mesh_transport_key_and_virtual_address_iterator_next(&mesh_transport_key_it);
488     const mesh_transport_key_t * message_key = mesh_transport_key_it.key;
489 
490     if (message_key->akf){
491         transport_segmented_setup_application_nonce(application_nonce, (mesh_pdu_t *) incoming_access_pdu_encrypted);
492     } else {
493         transport_segmented_setup_device_nonce(application_nonce, (mesh_pdu_t *) incoming_access_pdu_encrypted);
494     }
495 
496     // store application / device key index
497     mesh_print_hex("AppOrDevKey", message_key->key, 16);
498     incoming_access_pdu_decrypted->appkey_index = message_key->appkey_index;
499 
500     mesh_print_hex("EncAccessPayload", upper_transport_pdu_data, upper_transport_pdu_len);
501 
502     // decrypt ccm
503     crypto_active = 1;
504     uint16_t aad_len  = 0;
505     if (mesh_network_address_virtual(mesh_access_dst(incoming_access_pdu_decrypted))){
506         aad_len  = 16;
507     }
508     btstack_crypto_ccm_init(&ccm, message_key->key, application_nonce, upper_transport_pdu_len, aad_len, incoming_access_pdu_decrypted->transmic_len);
509 
510     if (aad_len){
511         btstack_crypto_ccm_digest(&ccm, (uint8_t *) mesh_transport_key_it.address->label_uuid, aad_len, &mesh_upper_transport_validate_segmented_message_digest, NULL);
512     } else {
513         mesh_upper_transport_validate_segmented_message_digest(NULL);
514     }
515 }
516 
517 static void mesh_upper_transport_process_segmented_message(void){
518     // copy original pdu
519     (void)memcpy(incoming_access_pdu_decrypted, incoming_access_pdu_encrypted,
520                  sizeof(mesh_access_pdu_t));
521 
522     //
523     uint8_t * upper_transport_pdu     =  incoming_access_pdu_decrypted->data;
524     uint8_t   upper_transport_pdu_len = incoming_access_pdu_decrypted->len - incoming_access_pdu_decrypted->transmic_len;
525     mesh_print_hex("Upper Transport pdu", upper_transport_pdu, upper_transport_pdu_len);
526 
527     uint8_t aid = incoming_access_pdu_decrypted->akf_aid_control & 0x3f;
528     uint8_t akf = (incoming_access_pdu_decrypted->akf_aid_control & 0x40) >> 6;
529 
530     printf("AKF: %u\n",   akf);
531     printf("AID: %02x\n", aid);
532 
533     mesh_transport_key_and_virtual_address_iterator_init(&mesh_transport_key_it, mesh_access_dst(incoming_access_pdu_decrypted),
534                                                          incoming_access_pdu_decrypted->netkey_index, akf, aid);
535     mesh_upper_transport_validate_segmented_message();
536 }
537 
538 static void mesh_upper_transport_message_received(mesh_pdu_t * pdu){
539     btstack_linked_list_add_tail(&upper_transport_incoming, (btstack_linked_item_t*) pdu);
540     mesh_upper_transport_run();
541 }
542 
543 static void mesh_upper_transport_send_unsegmented_access_pdu_ccm(void * arg){
544     crypto_active = 0;
545 
546     mesh_unsegmented_pdu_t * unsegmented_pdu = (mesh_unsegmented_pdu_t *) arg;
547     mesh_network_pdu_t * network_pdu = unsegmented_pdu->segment;
548 
549     uint8_t * upper_transport_pdu     = mesh_network_pdu_data(network_pdu) + 1;
550     uint8_t   upper_transport_pdu_len = mesh_network_pdu_len(network_pdu)  - 1;
551     mesh_print_hex("EncAccessPayload", upper_transport_pdu, upper_transport_pdu_len);
552     // store TransMIC
553     btstack_crypto_ccm_get_authentication_value(&ccm, &upper_transport_pdu[upper_transport_pdu_len]);
554     mesh_print_hex("TransMIC", &upper_transport_pdu[upper_transport_pdu_len], 4);
555     network_pdu->len        += 4;
556     upper_transport_pdu_len += 4;
557     mesh_print_hex("UpperTransportPDU", upper_transport_pdu, upper_transport_pdu_len);
558     // send network pdu
559     mesh_lower_transport_send_pdu((mesh_pdu_t*) unsegmented_pdu);
560 }
561 
562 static void mesh_upper_transport_send_segmented_pdu(mesh_access_pdu_t * access_pdu){
563     outgoing_segmented_access_pdu = access_pdu;
564     mesh_segmented_pdu_t * message_pdu   = &outgoing_segmented_message_singleton;
565     message_pdu->pdu_header.pdu_type = MESH_PDU_TYPE_SEGMENTED;
566 
567     // convert mesh_access_pdu_t into mesh_segmented_pdu_t
568     mesh_segmented_append_payload(access_pdu->data, access_pdu->len, &message_pdu->segments);
569 
570     // copy meta
571     message_pdu->len = access_pdu->len;
572     message_pdu->netkey_index = access_pdu->netkey_index;
573     message_pdu->transmic_len = access_pdu->transmic_len;
574     message_pdu->akf_aid_control = access_pdu->akf_aid_control;
575     message_pdu->flags = access_pdu->flags;
576     (void)memcpy(message_pdu->network_header, access_pdu->network_header, 9);
577 
578     mesh_lower_transport_send_pdu((mesh_pdu_t*) message_pdu);
579 }
580 
581 static void mesh_upper_transport_send_segmented_access_pdu_ccm(void * arg){
582     crypto_active = 0;
583 
584     mesh_access_pdu_t * access_pdu = (mesh_access_pdu_t *) arg;
585     mesh_print_hex("EncAccessPayload", access_pdu->data, access_pdu->len);
586     // store TransMIC
587     btstack_crypto_ccm_get_authentication_value(&ccm, &access_pdu->data[access_pdu->len]);
588     mesh_print_hex("TransMIC", &access_pdu->data[access_pdu->len], access_pdu->transmic_len);
589     access_pdu->len += access_pdu->transmic_len;
590     mesh_print_hex("UpperTransportPDU", access_pdu->data, access_pdu->len);
591     mesh_upper_transport_send_segmented_pdu(access_pdu);
592 }
593 
594 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,
595                           const uint8_t * control_pdu_data, uint16_t control_pdu_len){
596 
597     if (control_pdu_len > 11) return 1;
598 
599     const mesh_network_key_t * network_key = mesh_network_key_list_get(netkey_index);
600     if (!network_key) return 1;
601 
602     uint8_t transport_pdu_data[12];
603     transport_pdu_data[0] = opcode;
604     (void)memcpy(&transport_pdu_data[1], control_pdu_data, control_pdu_len);
605     uint16_t transport_pdu_len = control_pdu_len + 1;
606 
607     // setup network_pdu
608     mesh_network_setup_pdu(network_pdu, netkey_index, network_key->nid, 1, ttl, 0, src, dest, transport_pdu_data, transport_pdu_len);
609 
610     return 0;
611 }
612 
613 #if 0
614 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,
615                           const uint8_t * control_pdu_data, uint16_t control_pdu_len){
616 
617     if (control_pdu_len > 256) return 1;
618 
619     const mesh_network_key_t * network_key = mesh_network_key_list_get(netkey_index);
620     if (!network_key) return 1;
621 
622     (void)memcpy(transport_pdu->data, control_pdu_data, control_pdu_len);
623     transport_pdu->len = control_pdu_len;
624     transport_pdu->netkey_index = netkey_index;
625     transport_pdu->akf_aid_control = opcode;
626     transport_pdu->transmic_len = 0;    // no TransMIC for control
627     mesh_transport_set_nid_ivi(transport_pdu, network_key->nid);
628     mesh_transport_set_src(transport_pdu, src);
629     mesh_transport_set_dest(transport_pdu, dest);
630     mesh_transport_set_ctl_ttl(transport_pdu, 0x80 | ttl);
631 
632     return 0;
633 }
634 #endif
635 
636 uint8_t mesh_upper_transport_setup_control_pdu(mesh_pdu_t * pdu, uint16_t netkey_index,
637                                                uint8_t ttl, uint16_t src, uint16_t dest, uint8_t opcode, const uint8_t * control_pdu_data, uint16_t control_pdu_len){
638     switch (pdu->pdu_type){
639         case MESH_PDU_TYPE_NETWORK:
640             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);
641         default:
642             btstack_assert(0);
643             return 1;
644     }
645 }
646 
647 static uint8_t mesh_upper_transport_setup_unsegmented_access_pdu_header(mesh_unsegmented_pdu_t * unsegmented_pdu, uint16_t netkey_index,
648                                                                         uint16_t appkey_index, uint8_t ttl, uint16_t src, uint16_t dest){
649 
650     mesh_network_pdu_t * network_pdu = unsegmented_pdu->segment;
651 
652     // get app or device key
653     const mesh_transport_key_t * appkey;
654     appkey = mesh_transport_key_get(appkey_index);
655     if (appkey == NULL){
656         printf("appkey_index %x unknown\n", appkey_index);
657         return 1;
658     }
659     uint8_t akf_aid = (appkey->akf << 6) | appkey->aid;
660 
661     // lookup network by netkey_index
662     const mesh_network_key_t * network_key = mesh_network_key_list_get(netkey_index);
663     if (!network_key) return 1;
664 
665     unsegmented_pdu->appkey_index = appkey_index;
666 
667     network_pdu->data[9] = akf_aid;
668     // setup network_pdu
669     mesh_network_setup_pdu_header(network_pdu, netkey_index, network_key->nid, 0, ttl, 0, src, dest);
670     return 0;
671 }
672 
673 static uint8_t mesh_upper_transport_setup_unsegmented_access_pdu(mesh_unsegmented_pdu_t * unsegmented_pdu, uint16_t netkey_index, uint16_t appkey_index, uint8_t ttl, uint16_t src, uint16_t dest,
674                                                                  const uint8_t * access_pdu_data, uint8_t access_pdu_len){
675 
676     int status = mesh_upper_transport_setup_unsegmented_access_pdu_header(unsegmented_pdu, netkey_index, appkey_index, ttl, src, dest);
677     if (status) return status;
678 
679     // store in unsegmented pdu
680     mesh_network_pdu_t * network_pdu = unsegmented_pdu->segment;
681     (void)memcpy(&network_pdu->data[10], access_pdu_data, access_pdu_len);
682     network_pdu->len = 10 + access_pdu_len;
683     return 0;
684 }
685 
686 static uint8_t mesh_upper_transport_setup_segmented_access_pdu_header(mesh_access_pdu_t * access_pdu, uint16_t netkey_index,
687     uint16_t appkey_index, uint8_t ttl, uint16_t src, uint16_t dest, uint8_t szmic){
688 
689     // get app or device key
690     const mesh_transport_key_t *appkey;
691     appkey = mesh_transport_key_get(appkey_index);
692     if (appkey == NULL) {
693         printf("[!] Upper transport, setup segmented Access PDU - appkey_index %x unknown\n", appkey_index);
694         return 1;
695     }
696     uint8_t akf_aid = (appkey->akf << 6) | appkey->aid;
697 
698     // lookup network by netkey_index
699     const mesh_network_key_t *network_key = mesh_network_key_list_get(netkey_index);
700     if (!network_key) return 1;
701     if (network_key == NULL) {
702         printf("[!] Upper transport, setup segmented Access PDU - netkey_index %x unknown\n", appkey_index);
703         return 1;
704     }
705 
706     const uint8_t trans_mic_len = szmic ? 8 : 4;
707 
708     // store in transport pdu
709     access_pdu->transmic_len = trans_mic_len;
710     access_pdu->netkey_index = netkey_index;
711     access_pdu->appkey_index = appkey_index;
712     access_pdu->akf_aid_control = akf_aid;
713     mesh_access_set_nid_ivi(access_pdu, network_key->nid | ((mesh_get_iv_index_for_tx() & 1) << 7));
714     mesh_access_set_src(access_pdu, src);
715     mesh_access_set_dest(access_pdu, dest);
716     mesh_access_set_ctl_ttl(access_pdu, ttl);
717     return 0;
718 }
719 
720 static uint8_t mesh_upper_transport_setup_upper_segmented_access_pdu_header(mesh_upper_transport_pdu_t * upper_pdu, uint16_t netkey_index,
721                                                                       uint16_t appkey_index, uint8_t ttl, uint16_t src, uint16_t dest, uint8_t szmic){
722 
723     // get app or device key
724     const mesh_transport_key_t *appkey;
725     appkey = mesh_transport_key_get(appkey_index);
726     if (appkey == NULL) {
727         printf("[!] Upper transport, setup segmented Access PDU - appkey_index %x unknown\n", appkey_index);
728         return 1;
729     }
730     uint8_t akf_aid = (appkey->akf << 6) | appkey->aid;
731 
732     // lookup network by netkey_index
733     const mesh_network_key_t *network_key = mesh_network_key_list_get(netkey_index);
734     if (!network_key) return 1;
735     if (network_key == NULL) {
736         printf("[!] Upper transport, setup segmented Access PDU - netkey_index %x unknown\n", appkey_index);
737         return 1;
738     }
739 
740     const uint8_t trans_mic_len = szmic ? 8 : 4;
741 
742     // store in transport pdu
743     upper_pdu->ivi_nid = network_key->nid | ((mesh_get_iv_index_for_tx() & 1) << 7);
744     upper_pdu->ctl_ttl = ttl;
745     upper_pdu->src = src;
746     upper_pdu->dst = dest;
747     upper_pdu->transmic_len = trans_mic_len;
748     upper_pdu->netkey_index = netkey_index;
749     upper_pdu->appkey_index = appkey_index;
750     upper_pdu->akf_aid_control = akf_aid;
751     return 0;
752 }
753 
754 static uint8_t mesh_upper_transport_setup_segmented_access_pdu(mesh_access_pdu_t * access_pdu, uint16_t netkey_index, uint16_t appkey_index, uint8_t ttl, uint16_t src, uint16_t dest,
755                                                                uint8_t szmic, const uint8_t * access_pdu_data, uint8_t access_pdu_len){
756     int status = mesh_upper_transport_setup_segmented_access_pdu_header(access_pdu, netkey_index, appkey_index, ttl, src, dest, szmic);
757     if (status) return status;
758 
759     // store in transport pdu
760     (void)memcpy(access_pdu->data, access_pdu_data, access_pdu_len);
761     access_pdu->len = access_pdu_len;
762     return 0;
763 }
764 
765 static uint8_t mesh_upper_transport_setup_upper_segmented_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,
766                                                                uint8_t szmic, const uint8_t * access_pdu_data, uint8_t access_pdu_len){
767     int status = mesh_upper_transport_setup_upper_segmented_access_pdu_header(upper_pdu, netkey_index, appkey_index, ttl, src, dest, szmic);
768     if (status) return status;
769 
770     // store in transport pdu
771     uint16_t offset = 0;
772     mesh_segmented_append_payload(access_pdu_data, access_pdu_len, &upper_pdu->payload.segments);
773     upper_pdu->len = access_pdu_len;
774     return 0;
775 }
776 
777 
778 uint8_t mesh_upper_transport_setup_access_pdu_header(mesh_pdu_t * pdu, uint16_t netkey_index, uint16_t appkey_index,
779                                               uint8_t ttl, uint16_t src, uint16_t dest, uint8_t szmic){
780     switch (pdu->pdu_type){
781         case MESH_PDU_TYPE_ACCESS:
782             return mesh_upper_transport_setup_segmented_access_pdu_header((mesh_access_pdu_t *) pdu, netkey_index, appkey_index, ttl, src, dest, szmic);
783         case MESH_PDU_TYPE_UNSEGMENTED:
784             return mesh_upper_transport_setup_unsegmented_access_pdu_header((mesh_unsegmented_pdu_t *) pdu, netkey_index, appkey_index, ttl, src, dest);
785         default:
786             btstack_assert(false);
787             return 1;
788     }
789 }
790 
791 uint8_t mesh_upper_transport_setup_access_pdu(mesh_pdu_t * pdu, uint16_t netkey_index, uint16_t appkey_index,
792                                               uint8_t ttl, uint16_t src, uint16_t dest, uint8_t szmic,
793                                               const uint8_t * access_pdu_data, uint8_t access_pdu_len){
794     switch (pdu->pdu_type){
795         case MESH_PDU_TYPE_UNSEGMENTED:
796             return mesh_upper_transport_setup_unsegmented_access_pdu((mesh_unsegmented_pdu_t *) pdu, netkey_index, appkey_index, ttl, src, dest, access_pdu_data, access_pdu_len);
797         case MESH_PDU_TYPE_ACCESS:
798             return mesh_upper_transport_setup_segmented_access_pdu((mesh_access_pdu_t *) pdu, netkey_index, appkey_index, ttl, src, dest, szmic, access_pdu_data, access_pdu_len);
799         case MESH_PDU_TYPE_UPPER_SEGMENTED_ACCESS:
800             return mesh_upper_transport_setup_upper_segmented_access_pdu((mesh_upper_transport_pdu_t *) pdu,  netkey_index, appkey_index, ttl, src, dest, szmic, access_pdu_data, access_pdu_len);
801         default:
802             btstack_assert(false);
803             return 1;
804     }
805 }
806 
807 static void mesh_upper_transport_send_unsegmented_access_pdu_digest(void * arg){
808     mesh_unsegmented_pdu_t * unsegmented_pdu = (mesh_unsegmented_pdu_t *) arg;
809     mesh_network_pdu_t * network_pdu = unsegmented_pdu->segment;
810     uint8_t * access_pdu_data = mesh_network_pdu_data(network_pdu) + 1;
811     uint16_t  access_pdu_len  = mesh_network_pdu_len(network_pdu)  - 1;
812     btstack_crypto_ccm_encrypt_block(&ccm, access_pdu_len, access_pdu_data, access_pdu_data, &mesh_upper_transport_send_unsegmented_access_pdu_ccm, unsegmented_pdu);
813 }
814 
815 static mesh_transport_key_t * mesh_upper_transport_get_outgoing_appkey(uint16_t netkey_index, uint16_t appkey_index){
816     // Device Key is fixed
817     if (appkey_index == MESH_DEVICE_KEY_INDEX) {
818         return mesh_transport_key_get(appkey_index);
819     }
820 
821     // Get key refresh state from subnet
822     mesh_subnet_t * subnet = mesh_subnet_get_by_netkey_index(netkey_index);
823     if (subnet == NULL) return NULL;
824 
825     // identify old and new app keys for given appkey_index
826     mesh_transport_key_t * old_key = NULL;
827     mesh_transport_key_t * new_key = NULL;
828     mesh_transport_key_iterator_t it;
829     mesh_transport_key_iterator_init(&it, netkey_index);
830     while (mesh_transport_key_iterator_has_more(&it)){
831         mesh_transport_key_t * transport_key = mesh_transport_key_iterator_get_next(&it);
832         if (transport_key->appkey_index != appkey_index) continue;
833         if (transport_key->old_key == 0) {
834             new_key = transport_key;
835         } else {
836             old_key = transport_key;
837         }
838     }
839 
840     // if no key is marked as old, just use the current one
841     if (old_key == NULL) return new_key;
842 
843     // use new key if it exists in phase two
844     if ((subnet->key_refresh == MESH_KEY_REFRESH_SECOND_PHASE) && (new_key != NULL)){
845         return new_key;
846     } else {
847         return old_key;
848     }
849 }
850 
851 static void mesh_upper_transport_send_unsegmented_access_pdu(mesh_unsegmented_pdu_t * unsegmented_pdu){
852 
853     mesh_network_pdu_t * network_pdu = unsegmented_pdu->segment;
854 
855     // if dst is virtual address, lookup label uuid and hash
856     uint16_t aad_len = 0;
857     mesh_virtual_address_t * virtual_address = NULL;
858     uint16_t dst = mesh_network_dst(network_pdu);
859     if (mesh_network_address_virtual(dst)){
860         virtual_address = mesh_virtual_address_for_pseudo_dst(dst);
861         if (!virtual_address){
862             printf("No virtual address register for pseudo dst %4x\n", dst);
863             btstack_memory_mesh_network_pdu_free(network_pdu);
864             return;
865         }
866         aad_len = 16;
867         big_endian_store_16(network_pdu->data, 7, virtual_address->hash);
868     }
869 
870     // reserve slot
871     mesh_lower_transport_reserve_slot();
872 
873     // Nonce for Access Payload based on Network Sequence number: needs to be fixed now and lower layers need to send packet in right order
874     uint32_t seq = mesh_sequence_number_next();
875     mesh_network_pdu_set_seq(network_pdu, seq);
876 
877     // Dump PDU
878     printf("[+] Upper transport, send unsegmented Access PDU - dest %04x, seq %06x\n", dst, mesh_network_seq(network_pdu));
879     mesh_print_hex("Access Payload", &network_pdu->data[10], network_pdu->len - 10);
880 
881     // setup nonce
882     uint16_t appkey_index = unsegmented_pdu->appkey_index;
883     if (appkey_index == MESH_DEVICE_KEY_INDEX){
884         transport_unsegmented_setup_device_nonce(application_nonce, network_pdu);
885     } else {
886         transport_unsegmented_setup_application_nonce(application_nonce, network_pdu);
887     }
888 
889     // get app or device key
890     const mesh_transport_key_t * appkey = mesh_upper_transport_get_outgoing_appkey(network_pdu->netkey_index, appkey_index);
891     mesh_print_hex("AppOrDevKey", appkey->key, 16);
892 
893     // encrypt ccm
894     uint8_t   trans_mic_len = 4;
895     uint16_t  access_pdu_len  = mesh_network_pdu_len(network_pdu)  - 1;
896     crypto_active = 1;
897 
898     btstack_crypto_ccm_init(&ccm, appkey->key, application_nonce, access_pdu_len, aad_len, trans_mic_len);
899     if (virtual_address){
900         mesh_print_hex("LabelUUID", virtual_address->label_uuid, 16);
901         btstack_crypto_ccm_digest(&ccm, virtual_address->label_uuid, 16, &mesh_upper_transport_send_unsegmented_access_pdu_digest, unsegmented_pdu);
902     } else {
903         mesh_upper_transport_send_unsegmented_access_pdu_digest(unsegmented_pdu);
904     }
905 }
906 
907 static void mesh_upper_transport_send_segmented_access_pdu_digest(void *arg){
908     mesh_access_pdu_t * access_pdu = (mesh_access_pdu_t *) arg;
909     uint16_t  access_pdu_len  = access_pdu->len;
910     uint8_t * access_pdu_data = access_pdu->data;
911     btstack_crypto_ccm_encrypt_block(&ccm, access_pdu_len,access_pdu_data, access_pdu_data, &mesh_upper_transport_send_segmented_access_pdu_ccm, access_pdu);
912 }
913 
914 static void mesh_upper_transport_send_segmented_access_pdu(mesh_access_pdu_t * access_pdu){
915 
916     // if dst is virtual address, lookup label uuid and hash
917     uint16_t aad_len = 0;
918     mesh_virtual_address_t * virtual_address = NULL;
919     uint16_t dst = mesh_access_dst(access_pdu);
920     if (mesh_network_address_virtual(dst)){
921         virtual_address = mesh_virtual_address_for_pseudo_dst(dst);
922         if (!virtual_address){
923             printf("No virtual address register for pseudo dst %4x\n", dst);
924             mesh_access_message_handler(MESH_TRANSPORT_PDU_SENT, MESH_TRANSPORT_STATUS_SEND_FAILED, (mesh_pdu_t *) access_pdu);
925             return;
926         }
927         // printf("Using hash %4x with LabelUUID: ", virtual_address->hash);
928         // printf_hexdump(virtual_address->label_uuid, 16);
929         aad_len = 16;
930         big_endian_store_16(access_pdu->network_header, 7, virtual_address->hash);
931     }
932 
933     // get app or device key
934     uint16_t appkey_index = access_pdu->appkey_index;
935     const mesh_transport_key_t * appkey = mesh_upper_transport_get_outgoing_appkey(access_pdu->netkey_index, appkey_index);
936     if (appkey == NULL){
937         printf("AppKey %04x not found, drop message\n", appkey_index);
938         mesh_access_message_handler(MESH_TRANSPORT_PDU_SENT, MESH_TRANSPORT_STATUS_SEND_FAILED, (mesh_pdu_t *) access_pdu);
939         return;
940     }
941 
942     // reserve slot
943     mesh_lower_transport_reserve_slot();
944 
945     // reserve one sequence number, which is also used to encrypt access payload
946     uint32_t seq = mesh_sequence_number_next();
947     access_pdu->flags |= MESH_TRANSPORT_FLAG_SEQ_RESERVED;
948     mesh_access_set_seq(access_pdu, seq);
949 
950     // Dump PDU
951     printf("[+] Upper transport, send segmented Access PDU - dest %04x, seq %06x\n", dst, mesh_access_seq(access_pdu));
952     mesh_print_hex("Access Payload", access_pdu->data, access_pdu->len);
953 
954     // setup nonce - uses dst, so after pseudo address translation
955     if (appkey_index == MESH_DEVICE_KEY_INDEX){
956         transport_segmented_setup_device_nonce(application_nonce, (mesh_pdu_t *) access_pdu);
957     } else {
958         transport_segmented_setup_application_nonce(application_nonce, (mesh_pdu_t *) access_pdu);
959     }
960 
961     // Dump key
962     mesh_print_hex("AppOrDevKey", appkey->key, 16);
963 
964     // encrypt ccm
965     uint8_t   transmic_len    = access_pdu->transmic_len;
966     uint16_t  access_pdu_len  = access_pdu->len;
967     crypto_active = 1;
968     btstack_crypto_ccm_init(&ccm, appkey->key, application_nonce, access_pdu_len, aad_len, transmic_len);
969     if (virtual_address){
970         mesh_print_hex("LabelUUID", virtual_address->label_uuid, 16);
971         btstack_crypto_ccm_digest(&ccm, virtual_address->label_uuid, 16, &mesh_upper_transport_send_segmented_access_pdu_digest, access_pdu);
972     } else {
973         mesh_upper_transport_send_segmented_access_pdu_digest(access_pdu);
974     }
975 }
976 
977 static void mesh_upper_transport_send_upper_segmented_pdu(mesh_upper_transport_pdu_t * upper_pdu){
978 
979     // TODO: store upper pdu in outgoing pdus active or similar
980     // outgoing_segmented_access_pdu = upper_pdu;
981 
982     mesh_segmented_pdu_t * message_pdu   = &outgoing_segmented_message_singleton;
983     message_pdu->pdu_header.pdu_type = MESH_PDU_TYPE_SEGMENTED;
984 
985     // convert mesh_access_pdu_t into mesh_segmented_pdu_t
986     mesh_segmented_append_payload(crypto_buffer, upper_pdu->len, &message_pdu->segments);
987 
988     // copy meta
989     message_pdu->len = upper_pdu->len;
990     message_pdu->netkey_index = upper_pdu->netkey_index;
991     message_pdu->transmic_len = upper_pdu->transmic_len;
992     message_pdu->akf_aid_control = upper_pdu->akf_aid_control;
993     message_pdu->flags = upper_pdu->flags;
994 
995     // setup message_pdu header
996     // (void)memcpy(message_pdu->network_header, upper_pdu->network_header, 9);
997     // TODO: use fields in mesh_segmented_pdu_t and setup network header in lower transport
998     message_pdu->network_header[0] = upper_pdu->ivi_nid;
999     message_pdu->network_header[1] = upper_pdu->ctl_ttl;
1000     big_endian_store_24(message_pdu->network_header, 2, upper_pdu->seq);
1001     big_endian_store_16(message_pdu->network_header, 5, upper_pdu->src);
1002     big_endian_store_16(message_pdu->network_header, 7, upper_pdu->dst);
1003 
1004     mesh_lower_transport_send_pdu((mesh_pdu_t*) message_pdu);
1005 }
1006 
1007 static void mesh_upper_transport_send_upper_segmented_access_pdu_ccm(void * arg){
1008     crypto_active = 0;
1009 
1010     mesh_upper_transport_pdu_t * upper_pdu = (mesh_upper_transport_pdu_t *) arg;
1011     mesh_print_hex("EncAccessPayload", crypto_buffer, upper_pdu->len);
1012     // store TransMIC
1013     btstack_crypto_ccm_get_authentication_value(&ccm, &crypto_buffer[upper_pdu->len]);
1014     mesh_print_hex("TransMIC", &crypto_buffer[upper_pdu->len], upper_pdu->transmic_len);
1015     upper_pdu->len += upper_pdu->transmic_len;
1016     mesh_print_hex("UpperTransportPDU", crypto_buffer, upper_pdu->len);
1017     mesh_upper_transport_send_upper_segmented_pdu(upper_pdu);
1018 }
1019 
1020 static void mesh_upper_transport_send_upper_segmented_access_pdu_digest(void *arg){
1021     mesh_upper_transport_pdu_t * upper_pdu = (mesh_upper_transport_pdu_t *) arg;
1022     uint16_t  access_pdu_len  = upper_pdu->len;
1023     btstack_crypto_ccm_encrypt_block(&ccm, access_pdu_len, crypto_buffer, crypto_buffer, &mesh_upper_transport_send_upper_segmented_access_pdu_ccm, upper_pdu);
1024 }
1025 
1026 static void mesh_upper_transport_send_upper_segmented_access_pdu(mesh_upper_transport_pdu_t * upper_pdu){
1027 
1028     // if dst is virtual address, lookup label uuid and hash
1029     uint16_t aad_len = 0;
1030     mesh_virtual_address_t * virtual_address = NULL;
1031     if (mesh_network_address_virtual(upper_pdu->dst)){
1032         virtual_address = mesh_virtual_address_for_pseudo_dst(upper_pdu->dst);
1033         if (!virtual_address){
1034             printf("No virtual address register for pseudo dst %4x\n", upper_pdu->dst);
1035             mesh_access_message_handler(MESH_TRANSPORT_PDU_SENT, MESH_TRANSPORT_STATUS_SEND_FAILED, (mesh_pdu_t *) upper_pdu);
1036             return;
1037         }
1038         // printf("Using hash %4x with LabelUUID: ", virtual_address->hash);
1039         // printf_hexdump(virtual_address->label_uuid, 16);
1040         aad_len = 16;
1041         upper_pdu->dst = virtual_address->hash;
1042     }
1043 
1044     // get app or device key
1045     uint16_t appkey_index = upper_pdu->appkey_index;
1046     const mesh_transport_key_t * appkey = mesh_upper_transport_get_outgoing_appkey(upper_pdu->netkey_index, appkey_index);
1047     if (appkey == NULL){
1048         printf("AppKey %04x not found, drop message\n", appkey_index);
1049         mesh_access_message_handler(MESH_TRANSPORT_PDU_SENT, MESH_TRANSPORT_STATUS_SEND_FAILED, (mesh_pdu_t *) upper_pdu);
1050         return;
1051     }
1052 
1053     // reserve slot
1054     mesh_lower_transport_reserve_slot();
1055 
1056     // reserve one sequence number, which is also used to encrypt access payload
1057     uint32_t seq = mesh_sequence_number_next();
1058     upper_pdu->flags |= MESH_TRANSPORT_FLAG_SEQ_RESERVED;
1059     upper_pdu->seq = seq;
1060 
1061     // also reserves crypto_buffer
1062     crypto_active = 1;
1063 
1064     // flatten segmented pdu into crypto buffer
1065     uint16_t payload_len = mesh_upper_pdu_flatten(upper_pdu, crypto_buffer, sizeof(crypto_buffer));
1066     btstack_assert(payload_len == upper_pdu->len);
1067 
1068     // Dump PDU
1069     printf("[+] Upper transport, send upper segmented Access PDU - dest %04x, seq %06x\n", upper_pdu->dst, upper_pdu->seq);
1070     mesh_print_hex("Access Payload", crypto_buffer, upper_pdu->len);
1071 
1072     // setup nonce - uses dst, so after pseudo address translation
1073     if (appkey_index == MESH_DEVICE_KEY_INDEX){
1074         transport_segmented_setup_device_nonce(application_nonce, (mesh_pdu_t *) upper_pdu);
1075     } else {
1076         transport_segmented_setup_application_nonce(application_nonce, (mesh_pdu_t *) upper_pdu);
1077     }
1078 
1079     // Dump key
1080     mesh_print_hex("AppOrDevKey", appkey->key, 16);
1081 
1082     // encrypt ccm
1083     uint8_t   transmic_len    = upper_pdu->transmic_len;
1084     uint16_t  access_pdu_len  = upper_pdu->len;
1085     btstack_crypto_ccm_init(&ccm, appkey->key, application_nonce, access_pdu_len, aad_len, transmic_len);
1086     if (virtual_address){
1087         mesh_print_hex("LabelUUID", virtual_address->label_uuid, 16);
1088         btstack_crypto_ccm_digest(&ccm, virtual_address->label_uuid, 16, &mesh_upper_transport_send_upper_segmented_access_pdu_digest, upper_pdu);
1089     } else {
1090         mesh_upper_transport_send_upper_segmented_access_pdu_digest(upper_pdu);
1091     }
1092 }
1093 
1094 static void mesh_upper_transport_send_unsegmented_control_pdu(mesh_network_pdu_t * network_pdu){
1095     // reserve slot
1096     mesh_lower_transport_reserve_slot();
1097     // reserve sequence number
1098     uint32_t seq = mesh_sequence_number_next();
1099     mesh_network_pdu_set_seq(network_pdu, seq);
1100     // Dump PDU
1101     uint8_t opcode = network_pdu->data[9];
1102     printf("[+] Upper transport, send unsegmented Control PDU %p - seq %06x opcode %02x\n", network_pdu, seq, opcode);
1103     mesh_print_hex("Access Payload", &network_pdu->data[10], network_pdu->len - 10);
1104     // wrap into mesh-unsegmented-pdu
1105     outgoing_unsegmented_pdu.pdu_header.pdu_type = MESH_PDU_TYPE_UNSEGMENTED;
1106     outgoing_unsegmented_pdu.segment = network_pdu;
1107     outgoing_unsegmented_pdu.flags = MESH_TRANSPORT_FLAG_CONTROL;
1108 
1109     // send
1110      mesh_lower_transport_send_pdu((mesh_pdu_t *) &outgoing_unsegmented_pdu);
1111 }
1112 
1113 #if 0
1114 static void mesh_upper_transport_send_segmented_control_pdu(mesh_transport_pdu_t * transport_pdu){
1115     // reserve slot
1116     mesh_lower_transport_reserve_slot();
1117     // reserve sequence number
1118     uint32_t seq = mesh_sequence_number_next();
1119     transport_pdu->flags |= MESH_TRANSPORT_FLAG_SEQ_RESERVED;
1120     mesh_transport_set_seq(transport_pdu, seq);
1121     // Dump PDU
1122     uint8_t opcode = transport_pdu->data[0];
1123     printf("[+] Upper transport, send segmented Control PDU %p - seq %06x opcode %02x\n", transport_pdu, seq, opcode);
1124     mesh_print_hex("Access Payload", &transport_pdu->data[1], transport_pdu->len - 1);
1125     // send
1126     btstack_assert(false);
1127     // mesh_upper_transport_send_segmented_pdu(transport_pdu);
1128 }
1129 #endif
1130 
1131 static void mesh_upper_transport_run(void){
1132 
1133     while(!btstack_linked_list_empty(&upper_transport_incoming)){
1134 
1135         if (crypto_active) return;
1136 
1137         // get next message
1138         mesh_pdu_t * pdu =  (mesh_pdu_t *) btstack_linked_list_pop(&upper_transport_incoming);
1139         mesh_network_pdu_t   * network_pdu;
1140         mesh_segmented_pdu_t   * message_pdu;
1141         mesh_unsegmented_pdu_t * unsegmented_pdu;
1142         switch (pdu->pdu_type){
1143             case MESH_PDU_TYPE_UNSEGMENTED:
1144                 unsegmented_pdu = (mesh_unsegmented_pdu_t *) pdu;
1145                 network_pdu = unsegmented_pdu->segment;
1146                 btstack_assert(network_pdu != NULL);
1147                 // control?
1148                 if (mesh_network_control(network_pdu)) {
1149 
1150                     incoming_control_pdu =  &incoming_control_pdu_singleton;
1151                     incoming_control_pdu->pdu_header.pdu_type = MESH_PDU_TYPE_CONTROL;
1152                     incoming_control_pdu->len =  network_pdu->len;
1153                     incoming_control_pdu->netkey_index =  network_pdu->netkey_index;
1154 
1155                     uint8_t * lower_transport_pdu = mesh_network_pdu_data(network_pdu);
1156 
1157                     incoming_control_pdu->akf_aid_control = lower_transport_pdu[0];
1158                     incoming_control_pdu->len = network_pdu->len - 10; // 9 header + 1 opcode
1159                     (void)memcpy(incoming_control_pdu->data, &lower_transport_pdu[1], incoming_control_pdu->len);
1160 
1161                     // copy meta data into encrypted pdu buffer
1162                     (void)memcpy(incoming_control_pdu->network_header, network_pdu->data, 9);
1163 
1164                     mesh_print_hex("Assembled payload", incoming_control_pdu->data, incoming_control_pdu->len);
1165 
1166                     // free mesh message
1167                     mesh_lower_transport_message_processed_by_higher_layer(pdu);
1168 
1169                     btstack_assert(mesh_control_message_handler != NULL);
1170                     mesh_pdu_t * pdu = (mesh_pdu_t*) incoming_control_pdu;
1171                     mesh_control_message_handler(MESH_TRANSPORT_PDU_RECEIVED, MESH_TRANSPORT_STATUS_SUCCESS, pdu);
1172 
1173                 } else {
1174 
1175                     incoming_access_pdu_encrypted = &incoming_access_pdu_encrypted_singleton;
1176                     incoming_access_pdu_encrypted->pdu_header.pdu_type = MESH_PDU_TYPE_ACCESS;
1177                     incoming_access_pdu_decrypted = &incoming_access_pdu_decrypted_singleton;
1178 
1179                     incoming_access_pdu_encrypted->netkey_index = network_pdu->netkey_index;
1180                     incoming_access_pdu_encrypted->transmic_len = 4;
1181 
1182                     uint8_t * lower_transport_pdu = mesh_network_pdu_data(network_pdu);
1183 
1184                     incoming_access_pdu_encrypted->akf_aid_control = lower_transport_pdu[0];
1185                     incoming_access_pdu_encrypted->len = network_pdu->len - 10; // 9 header + 1 AID
1186                     (void)memcpy(incoming_access_pdu_encrypted->data, &lower_transport_pdu[1], incoming_access_pdu_encrypted->len);
1187 
1188                     // copy meta data into encrypted pdu buffer
1189                     (void)memcpy(incoming_access_pdu_encrypted->network_header, network_pdu->data, 9);
1190 
1191                     mesh_print_hex("Assembled payload", incoming_access_pdu_encrypted->data, incoming_access_pdu_encrypted->len);
1192 
1193                     // free mesh message
1194                     mesh_lower_transport_message_processed_by_higher_layer(pdu);
1195 
1196                     // get encoded transport pdu and start processing
1197                     mesh_upper_transport_process_segmented_message();
1198                 }
1199                 break;
1200             case MESH_PDU_TYPE_SEGMENTED:
1201                 message_pdu = (mesh_segmented_pdu_t *) pdu;
1202                 uint8_t ctl = mesh_message_ctl(message_pdu);
1203                 if (ctl){
1204                     incoming_control_pdu=  &incoming_control_pdu_singleton;
1205                     incoming_control_pdu->pdu_header.pdu_type = MESH_PDU_TYPE_CONTROL;
1206 
1207                     // flatten
1208                     mesh_segmented_pdu_flatten(&message_pdu->segments, 8, incoming_control_pdu->data);
1209 
1210                     // copy meta data into encrypted pdu buffer
1211                     incoming_control_pdu->len =  message_pdu->len;
1212                     incoming_control_pdu->netkey_index =  message_pdu->netkey_index;
1213                     incoming_control_pdu->akf_aid_control =  message_pdu->akf_aid_control;
1214                     incoming_control_pdu->flags = 0;
1215                     (void)memcpy(incoming_control_pdu->network_header, message_pdu->network_header, 9);
1216 
1217                     mesh_print_hex("Assembled payload", incoming_control_pdu->data, incoming_control_pdu->len);
1218 
1219                     // free mesh message
1220                     mesh_lower_transport_message_processed_by_higher_layer((mesh_pdu_t *)message_pdu);
1221 
1222                     btstack_assert(mesh_control_message_handler != NULL);
1223                     mesh_pdu_t * pdu = (mesh_pdu_t*) incoming_control_pdu;
1224                     mesh_access_message_handler(MESH_TRANSPORT_PDU_RECEIVED, MESH_TRANSPORT_STATUS_SUCCESS, pdu);
1225 
1226                 } else {
1227 
1228                     incoming_access_pdu_encrypted = &incoming_access_pdu_encrypted_singleton;
1229                     incoming_access_pdu_encrypted->pdu_header.pdu_type = MESH_PDU_TYPE_ACCESS;
1230                     incoming_access_pdu_decrypted = &incoming_access_pdu_decrypted_singleton;
1231 
1232                     // flatten
1233                     mesh_segmented_pdu_flatten(&message_pdu->segments, 12, incoming_access_pdu_encrypted->data);
1234 
1235                     // copy meta data into encrypted pdu buffer
1236                     incoming_access_pdu_encrypted->len =  message_pdu->len;
1237                     incoming_access_pdu_encrypted->netkey_index =  message_pdu->netkey_index;
1238                     incoming_access_pdu_encrypted->transmic_len =  message_pdu->transmic_len;
1239                     incoming_access_pdu_encrypted->akf_aid_control =  message_pdu->akf_aid_control;
1240                     (void)memcpy(incoming_access_pdu_encrypted->network_header, message_pdu->network_header, 9);
1241 
1242                     mesh_print_hex("Assembled payload", incoming_access_pdu_encrypted->data, incoming_access_pdu_encrypted->len);
1243 
1244                     // free mesh message
1245                     mesh_lower_transport_message_processed_by_higher_layer((mesh_pdu_t *)message_pdu);
1246 
1247                     // get encoded transport pdu and start processing
1248                     mesh_upper_transport_process_segmented_message();
1249                 }
1250                 break;
1251             default:
1252                 btstack_assert(0);
1253                 break;
1254         }
1255     }
1256 
1257     while (!btstack_linked_list_empty(&upper_transport_outgoing)){
1258 
1259         if (crypto_active) break;
1260 
1261         if (outgoing_segmented_access_pdu != NULL) break;
1262 
1263         mesh_pdu_t * pdu =  (mesh_pdu_t *) btstack_linked_list_get_first_item(&upper_transport_outgoing);
1264         if (mesh_lower_transport_can_send_to_dest(mesh_pdu_dst(pdu)) == 0) break;
1265 
1266         (void) btstack_linked_list_pop(&upper_transport_outgoing);
1267 
1268         mesh_unsegmented_pdu_t * unsegmented_pdu;
1269 
1270         switch (pdu->pdu_type){
1271             case MESH_PDU_TYPE_NETWORK:
1272                 btstack_assert(mesh_pdu_ctl(pdu) != 0);
1273                 mesh_upper_transport_send_unsegmented_control_pdu((mesh_network_pdu_t *) pdu);
1274                 break;
1275             case MESH_PDU_TYPE_UNSEGMENTED:
1276                 unsegmented_pdu = ( mesh_unsegmented_pdu_t *) pdu;
1277                 btstack_assert((unsegmented_pdu->flags & MESH_TRANSPORT_FLAG_CONTROL) == 0);
1278                 mesh_upper_transport_send_unsegmented_access_pdu(unsegmented_pdu);
1279                 break;
1280             case MESH_PDU_TYPE_ACCESS:
1281                 if (mesh_pdu_ctl(pdu) != 0){
1282                     btstack_assert(false);
1283                 } else {
1284                     mesh_upper_transport_send_segmented_access_pdu((mesh_access_pdu_t *) pdu);
1285                 }
1286                 break;
1287             case MESH_PDU_TYPE_UPPER_SEGMENTED_ACCESS:
1288                 mesh_upper_transport_send_upper_segmented_access_pdu((mesh_upper_transport_pdu_t *) pdu);
1289                 break;
1290             default:
1291                 btstack_assert(false);
1292                 break;
1293         }
1294     }
1295 }
1296 
1297 
1298 
1299 static void mesh_upper_transport_pdu_handler(mesh_transport_callback_type_t callback_type, mesh_transport_status_t status, mesh_pdu_t * pdu){
1300     mesh_pdu_t * pdu_to_report;
1301     mesh_unsegmented_pdu_t * unsegmented_pdu;
1302     switch (callback_type){
1303         case MESH_TRANSPORT_PDU_RECEIVED:
1304             mesh_upper_transport_message_received(pdu);
1305             break;
1306         case MESH_TRANSPORT_PDU_SENT:
1307             switch (pdu->pdu_type){
1308                 case MESH_PDU_TYPE_SEGMENTED:
1309                     // free chunks
1310                     while (!btstack_linked_list_empty(&outgoing_segmented_message_singleton.segments)){
1311                         mesh_network_pdu_t * network_pdu = (mesh_network_pdu_t *) btstack_linked_list_pop(&outgoing_segmented_message_singleton.segments);
1312                         mesh_network_pdu_free(network_pdu);
1313                     }
1314                     // notify upper layer but use transport pdu
1315                     pdu_to_report = (mesh_pdu_t *) outgoing_segmented_access_pdu;
1316                     outgoing_segmented_access_pdu = NULL;
1317                     if (mesh_pdu_ctl(pdu_to_report)){
1318                         mesh_control_message_handler(callback_type, status, pdu_to_report);
1319                     } else {
1320                         mesh_access_message_handler(callback_type, status, pdu_to_report);
1321                     }
1322                     break;
1323                 case MESH_PDU_TYPE_UNSEGMENTED:
1324                     unsegmented_pdu = (mesh_unsegmented_pdu_t *) pdu;
1325                     if (unsegmented_pdu == &outgoing_unsegmented_pdu){
1326                         // notify upper layer but use network pdu (control pdu)
1327                         btstack_assert((unsegmented_pdu->flags & MESH_TRANSPORT_FLAG_CONTROL) != 0);
1328                         mesh_network_pdu_t * network_pdu = outgoing_unsegmented_pdu.segment;
1329                         outgoing_unsegmented_pdu.segment = NULL;
1330                         mesh_control_message_handler(callback_type, status, (mesh_pdu_t *) network_pdu);
1331                     } else {
1332                         btstack_assert((unsegmented_pdu->flags & MESH_TRANSPORT_FLAG_CONTROL) == 0);
1333                         mesh_access_message_handler(callback_type, status, pdu);
1334                     }
1335                     break;
1336                 default:
1337                     btstack_assert(false);
1338                     break;
1339             }
1340             mesh_upper_transport_run();
1341             break;
1342         default:
1343             break;
1344     }
1345 }
1346 
1347 void mesh_upper_transport_pdu_free(mesh_pdu_t * pdu){
1348     mesh_network_pdu_t   * network_pdu;
1349     mesh_segmented_pdu_t   * message_pdu;
1350     switch (pdu->pdu_type) {
1351         case MESH_PDU_TYPE_NETWORK:
1352             network_pdu = (mesh_network_pdu_t *) pdu;
1353             mesh_network_pdu_free(network_pdu);
1354             break;
1355         case MESH_PDU_TYPE_SEGMENTED:
1356             message_pdu = (mesh_segmented_pdu_t *) pdu;
1357             mesh_message_pdu_free(message_pdu);
1358         default:
1359             btstack_assert(false);
1360             break;
1361     }
1362 }
1363 
1364 void mesh_upper_transport_message_processed_by_higher_layer(mesh_pdu_t * pdu){
1365     crypto_active = 0;
1366     switch (pdu->pdu_type){
1367         case MESH_PDU_TYPE_ACCESS:
1368             mesh_upper_transport_process_access_message_done((mesh_access_pdu_t *) pdu);
1369         case MESH_PDU_TYPE_CONTROL:
1370             mesh_upper_transport_process_control_message_done((mesh_control_pdu_t *) pdu);
1371             break;
1372         default:
1373             btstack_assert(0);
1374             break;
1375     }
1376 }
1377 
1378 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)) {
1379     mesh_access_message_handler = callback;
1380 }
1381 
1382 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)){
1383     mesh_control_message_handler = callback;
1384 }
1385 
1386 void mesh_upper_transport_init(){
1387     mesh_lower_transport_set_higher_layer_handler(&mesh_upper_transport_pdu_handler);
1388 }
1389