xref: /btstack/src/mesh/mesh_upper_transport.c (revision 43d07e7f35b19927e6091f0b3495108fd5bcff9a)
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 // upper transport callbacks - in access layer
78 static void (*mesh_access_message_handler)( mesh_transport_callback_type_t callback_type, mesh_transport_status_t status, mesh_pdu_t * pdu);
79 static void (*mesh_control_message_handler)( mesh_transport_callback_type_t callback_type, mesh_transport_status_t status, mesh_pdu_t * pdu);
80 
81 //
82 static int crypto_active;
83 static uint8_t application_nonce[13];
84 static btstack_crypto_ccm_t ccm;
85 static uint8_t crypto_buffer[MESH_ACCESS_PAYLOAD_MAX];
86 
87 static mesh_transport_key_and_virtual_address_iterator_t mesh_transport_key_it;
88 
89 static mesh_access_pdu_t *      incoming_access_pdu_encrypted;
90 static mesh_access_pdu_t *      incoming_access_pdu_decrypted;
91 
92 static mesh_access_pdu_t        incoming_access_pdu_encrypted_singleton;
93 static mesh_access_pdu_t        incoming_access_pdu_decrypted_singleton;
94 
95 static mesh_control_pdu_t       incoming_control_pdu_singleton;
96 static mesh_control_pdu_t *     incoming_control_pdu;
97 
98 static mesh_segmented_pdu_t     outgoing_segmented_pdu_singleton;
99 
100 static mesh_segmented_pdu_t *   upper_transport_outgoing_segmented;
101 
102 // incoming unsegmented (network) and segmented (transport) control and access messages
103 static btstack_linked_list_t upper_transport_incoming;
104 
105 // outgoing unsegmented and segmented control and access messages
106 static btstack_linked_list_t upper_transport_outgoing;
107 
108 // outgoing upper transport messages that have been sent to lower transport and wait for sent event
109 static btstack_linked_list_t upper_transport_outgoing_active;
110 
111 // TODO: higher layer define used for assert
112 #define MESH_ACCESS_OPCODE_NOT_SET 0xFFFFFFFEu
113 
114 static void mesh_print_hex(const char * name, const uint8_t * data, uint16_t len){
115     printf("%-20s ", name);
116     printf_hexdump(data, len);
117 }
118 // static void mesh_print_x(const char * name, uint32_t value){
119 //     printf("%20s: 0x%x", name, (int) value);
120 // }
121 
122 static void mesh_transport_key_and_virtual_address_iterator_init(mesh_transport_key_and_virtual_address_iterator_t *it,
123                                                                  uint16_t dst, uint16_t netkey_index, uint8_t akf,
124                                                                  uint8_t aid) {
125     printf("KEY_INIT: dst %04x, akf %x, aid %x\n", dst, akf, aid);
126     // config
127     it->dst   = dst;
128     // init elements
129     it->key     = NULL;
130     it->address = NULL;
131     // init element iterators
132     mesh_transport_key_aid_iterator_init(&it->key_it, netkey_index, akf, aid);
133     // init address iterator
134     if (mesh_network_address_virtual(it->dst)){
135         mesh_virtual_address_iterator_init(&it->address_it, dst);
136         // get first key
137         if (mesh_transport_key_aid_iterator_has_more(&it->key_it)) {
138             it->key = mesh_transport_key_aid_iterator_get_next(&it->key_it);
139         }
140     }
141 }
142 
143 // cartesian product: keys x addressses
144 static int mesh_transport_key_and_virtual_address_iterator_has_more(mesh_transport_key_and_virtual_address_iterator_t * it){
145     if (mesh_network_address_virtual(it->dst)) {
146         // find next valid entry
147         while (true){
148             if (mesh_virtual_address_iterator_has_more(&it->address_it)) return 1;
149             if (!mesh_transport_key_aid_iterator_has_more(&it->key_it)) return 0;
150             // get next key
151             it->key = mesh_transport_key_aid_iterator_get_next(&it->key_it);
152             mesh_virtual_address_iterator_init(&it->address_it, it->dst);
153         }
154     } else {
155         return mesh_transport_key_aid_iterator_has_more(&it->key_it);
156     }
157 }
158 
159 static void mesh_transport_key_and_virtual_address_iterator_next(mesh_transport_key_and_virtual_address_iterator_t * it){
160     if (mesh_network_address_virtual(it->dst)) {
161         it->address = mesh_virtual_address_iterator_get_next(&it->address_it);
162     } else {
163         it->key = mesh_transport_key_aid_iterator_get_next(&it->key_it);
164     }
165 }
166 
167 // UPPER TRANSPORT
168 
169 uint16_t mesh_access_dst(mesh_access_pdu_t * access_pdu){
170     return big_endian_read_16(access_pdu->network_header, 7);
171 }
172 
173 uint16_t mesh_access_ctl(mesh_access_pdu_t * access_pdu){
174     return access_pdu->network_header[1] >> 7;
175 }
176 
177 uint32_t mesh_access_seq(mesh_access_pdu_t * access_pdu){
178     return big_endian_read_24(access_pdu->network_header, 2);
179 }
180 
181 void mesh_access_set_nid_ivi(mesh_access_pdu_t * access_pdu, uint8_t nid_ivi){
182     access_pdu->network_header[0] = nid_ivi;
183 }
184 void mesh_access_set_ctl_ttl(mesh_access_pdu_t * access_pdu, uint8_t ctl_ttl){
185     access_pdu->network_header[1] = ctl_ttl;
186 }
187 void mesh_access_set_seq(mesh_access_pdu_t * access_pdu, uint32_t seq){
188     big_endian_store_24(access_pdu->network_header, 2, seq);
189 }
190 void mesh_access_set_src(mesh_access_pdu_t * access_pdu, uint16_t src){
191     big_endian_store_16(access_pdu->network_header, 5, src);
192 }
193 void mesh_access_set_dest(mesh_access_pdu_t * access_pdu, uint16_t dest){
194     big_endian_store_16(access_pdu->network_header, 7, dest);
195 }
196 
197 static void mesh_segmented_pdu_flatten(btstack_linked_list_t * segments, uint8_t segment_len, uint8_t * buffer) {
198     // assemble payload
199     btstack_linked_list_iterator_t it;
200     btstack_linked_list_iterator_init(&it, segments);
201     while (btstack_linked_list_iterator_has_next(&it)) {
202         mesh_network_pdu_t *segment = (mesh_network_pdu_t *) btstack_linked_list_iterator_next(&it);
203         btstack_assert(segment->pdu_header.pdu_type == MESH_PDU_TYPE_NETWORK);
204         // get segment n
205         uint8_t *lower_transport_pdu = mesh_network_pdu_data(segment);
206         uint8_t seg_o = (big_endian_read_16(lower_transport_pdu, 2) >> 5) & 0x001f;
207         uint8_t *segment_data = &lower_transport_pdu[4];
208         (void) memcpy(&buffer[seg_o * segment_len], segment_data, segment_len);
209     }
210 }
211 
212 static uint16_t mesh_upper_pdu_flatten(mesh_upper_transport_pdu_t * upper_pdu, uint8_t * buffer, uint16_t buffer_len) {
213     // assemble payload
214     btstack_linked_list_iterator_t it;
215     btstack_linked_list_iterator_init(&it, &upper_pdu->segments);
216     uint16_t offset = 0;
217     while (btstack_linked_list_iterator_has_next(&it)) {
218         mesh_network_pdu_t *segment = (mesh_network_pdu_t *) btstack_linked_list_iterator_next(&it);
219         btstack_assert(segment->pdu_header.pdu_type == MESH_PDU_TYPE_NETWORK);
220         btstack_assert((offset + segment->len) <= buffer_len);
221         (void) memcpy(&buffer[offset], segment->data, segment->len);
222         offset += segment->len;
223     }
224     return offset;
225 }
226 
227 static void mesh_segmented_append_payload(const uint8_t * payload, uint16_t payload_len, btstack_linked_list_t * segments){
228     uint16_t payload_offset = 0;
229     uint16_t bytes_current_segment = 0;
230     mesh_network_pdu_t * network_pdu = (mesh_network_pdu_t *) btstack_linked_list_get_last_item(segments);
231     if (network_pdu){
232         bytes_current_segment = MESH_NETWORK_PAYLOAD_MAX - network_pdu->len;
233     }
234     while (payload_offset < payload_len){
235         if (bytes_current_segment == 0){
236             network_pdu = mesh_network_pdu_get();
237             btstack_assert(network_pdu != NULL);
238             btstack_linked_list_add_tail(segments, (btstack_linked_item_t *) network_pdu);
239             bytes_current_segment = MESH_NETWORK_PAYLOAD_MAX;
240         }
241         uint16_t bytes_to_copy = btstack_min(bytes_current_segment, payload_len - payload_offset);
242         (void) memcpy(&network_pdu->data[network_pdu->len], &payload[payload_offset], bytes_to_copy);
243         bytes_current_segment -= bytes_to_copy;
244         network_pdu->len += bytes_to_copy;
245         payload_offset += bytes_to_copy;
246     }
247 }
248 
249 // stub lower transport
250 
251 static void mesh_upper_transport_dump_pdus(const char *name, btstack_linked_list_t *list){
252     printf("List: %s:\n", name);
253     btstack_linked_list_iterator_t it;
254     btstack_linked_list_iterator_init(&it, list);
255     while (btstack_linked_list_iterator_has_next(&it)){
256         mesh_pdu_t * pdu = (mesh_pdu_t*) btstack_linked_list_iterator_next(&it);
257         printf("- %p\n", pdu);
258         // printf_hexdump( mesh_pdu_data(pdu), mesh_pdu_len(pdu));
259     }
260 }
261 
262 static void mesh_upper_transport_reset_pdus(btstack_linked_list_t *list){
263     while (!btstack_linked_list_empty(list)){
264         mesh_upper_transport_pdu_free((mesh_pdu_t *) btstack_linked_list_pop(list));
265     }
266 }
267 
268 void mesh_upper_transport_dump(void){
269     mesh_upper_transport_dump_pdus("upper_transport_incoming", &upper_transport_incoming);
270 }
271 
272 void mesh_upper_transport_reset(void){
273     crypto_active = 0;
274     mesh_upper_transport_reset_pdus(&upper_transport_incoming);
275 }
276 
277 static mesh_transport_key_t * mesh_upper_transport_get_outgoing_appkey(uint16_t netkey_index, uint16_t appkey_index){
278     // Device Key is fixed
279     if (appkey_index == MESH_DEVICE_KEY_INDEX) {
280         return mesh_transport_key_get(appkey_index);
281     }
282 
283     // Get key refresh state from subnet
284     mesh_subnet_t * subnet = mesh_subnet_get_by_netkey_index(netkey_index);
285     if (subnet == NULL) return NULL;
286 
287     // identify old and new app keys for given appkey_index
288     mesh_transport_key_t * old_key = NULL;
289     mesh_transport_key_t * new_key = NULL;
290     mesh_transport_key_iterator_t it;
291     mesh_transport_key_iterator_init(&it, netkey_index);
292     while (mesh_transport_key_iterator_has_more(&it)){
293         mesh_transport_key_t * transport_key = mesh_transport_key_iterator_get_next(&it);
294         if (transport_key->appkey_index != appkey_index) continue;
295         if (transport_key->old_key == 0) {
296             new_key = transport_key;
297         } else {
298             old_key = transport_key;
299         }
300     }
301 
302     // if no key is marked as old, just use the current one
303     if (old_key == NULL) return new_key;
304 
305     // use new key if it exists in phase two
306     if ((subnet->key_refresh == MESH_KEY_REFRESH_SECOND_PHASE) && (new_key != NULL)){
307         return new_key;
308     } else {
309         return old_key;
310     }
311 }
312 
313 static uint32_t iv_index_for_ivi_nid(uint8_t ivi_nid){
314     // get IV Index and IVI
315     uint32_t iv_index = mesh_get_iv_index();
316     int ivi = ivi_nid >> 7;
317 
318     // if least significant bit differs, use previous IV Index
319     if ((iv_index & 1 ) ^ ivi){
320         iv_index--;
321     }
322     return iv_index;
323 }
324 
325 static void transport_segmented_setup_nonce(uint8_t * nonce, const mesh_pdu_t * pdu){
326     mesh_access_pdu_t * access_pdu;
327     mesh_upper_transport_pdu_t * upper_pdu;
328     switch (pdu->pdu_type){
329         case MESH_PDU_TYPE_ACCESS:
330             access_pdu = (mesh_access_pdu_t *) pdu;
331             nonce[1] = access_pdu->transmic_len == 8 ? 0x80 : 0x00;
332             (void)memcpy(&nonce[2], &access_pdu->network_header[2], 7);
333             big_endian_store_32(nonce, 9, iv_index_for_ivi_nid(access_pdu->network_header[0]));
334             break;
335         case MESH_PDU_TYPE_UPPER_SEGMENTED_ACCESS:
336         case MESH_PDU_TYPE_UPPER_UNSEGMENTED_ACCESS:
337             upper_pdu = (mesh_upper_transport_pdu_t *) pdu;
338             nonce[1] = upper_pdu->transmic_len == 8 ? 0x80 : 0x00;
339             // 'network header'
340             big_endian_store_24(nonce, 2, upper_pdu->seq);
341             big_endian_store_16(nonce, 5, upper_pdu->src);
342             big_endian_store_16(nonce, 7, upper_pdu->dst);
343             big_endian_store_32(nonce, 9, iv_index_for_ivi_nid(upper_pdu->ivi_nid));
344             break;
345         default:
346             btstack_assert(0);
347             break;
348     }
349 }
350 
351 static void transport_segmented_setup_application_nonce(uint8_t * nonce, const mesh_pdu_t * pdu){
352     nonce[0] = 0x01;
353     transport_segmented_setup_nonce(nonce, pdu);
354     mesh_print_hex("AppNonce", nonce, 13);
355 }
356 
357 static void transport_segmented_setup_device_nonce(uint8_t * nonce, const mesh_pdu_t * pdu){
358     nonce[0] = 0x02;
359     transport_segmented_setup_nonce(nonce, pdu);
360     mesh_print_hex("DeviceNonce", nonce, 13);
361 }
362 
363 static void mesh_upper_transport_process_access_message_done(mesh_access_pdu_t *access_pdu){
364     crypto_active = 0;
365     btstack_assert(mesh_access_ctl(access_pdu) == 0);
366     incoming_access_pdu_encrypted = NULL;
367     mesh_upper_transport_run();
368 }
369 
370 static void mesh_upper_transport_process_control_message_done(mesh_control_pdu_t * control_pdu){
371     crypto_active = 0;
372     incoming_control_pdu = NULL;
373     mesh_upper_transport_run();
374 }
375 
376 static void mesh_upper_transport_validate_segmented_message_ccm(void * arg){
377     UNUSED(arg);
378 
379     uint8_t * upper_transport_pdu     = incoming_access_pdu_decrypted->data;
380     uint8_t   upper_transport_pdu_len = incoming_access_pdu_decrypted->len - incoming_access_pdu_decrypted->transmic_len;
381 
382     mesh_print_hex("Decrypted PDU", upper_transport_pdu, upper_transport_pdu_len);
383 
384     // store TransMIC
385     uint8_t trans_mic[8];
386     btstack_crypto_ccm_get_authentication_value(&ccm, trans_mic);
387     mesh_print_hex("TransMIC", trans_mic, incoming_access_pdu_decrypted->transmic_len);
388 
389     if (memcmp(trans_mic, &upper_transport_pdu[upper_transport_pdu_len], incoming_access_pdu_decrypted->transmic_len) == 0){
390         printf("TransMIC matches\n");
391 
392         // remove TransMIC from payload
393         incoming_access_pdu_decrypted->len -= incoming_access_pdu_decrypted->transmic_len;
394 
395         // if virtual address, update dst to pseudo_dst
396         if (mesh_network_address_virtual(mesh_access_dst(incoming_access_pdu_decrypted))){
397             big_endian_store_16(incoming_access_pdu_decrypted->network_header, 7, mesh_transport_key_it.address->pseudo_dst);
398         }
399 
400         // pass to upper layer
401         btstack_assert(mesh_access_message_handler != NULL);
402         mesh_pdu_t * pdu = (mesh_pdu_t*) incoming_access_pdu_decrypted;
403         mesh_access_message_handler(MESH_TRANSPORT_PDU_RECEIVED, MESH_TRANSPORT_STATUS_SUCCESS, pdu);
404 
405         printf("\n");
406 
407     } else {
408         uint8_t akf = incoming_access_pdu_decrypted->akf_aid_control & 0x40;
409         if (akf){
410             printf("TransMIC does not match, try next key\n");
411             mesh_upper_transport_validate_segmented_message();
412         } else {
413             printf("TransMIC does not match device key, done\n");
414             // done
415             mesh_upper_transport_process_access_message_done(incoming_access_pdu_decrypted);
416         }
417     }
418 }
419 
420 static void mesh_upper_transport_validate_segmented_message_digest(void * arg){
421     UNUSED(arg);
422     uint8_t   upper_transport_pdu_len      = incoming_access_pdu_encrypted->len - incoming_access_pdu_encrypted->transmic_len;
423     uint8_t * upper_transport_pdu_data_in  = incoming_access_pdu_encrypted->data;
424     uint8_t * upper_transport_pdu_data_out = incoming_access_pdu_decrypted->data;
425     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);
426 }
427 
428 static void mesh_upper_transport_validate_segmented_message(void){
429     uint8_t * upper_transport_pdu_data =  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     if (!mesh_transport_key_and_virtual_address_iterator_has_more(&mesh_transport_key_it)){
433         printf("No valid transport key found\n");
434         mesh_upper_transport_process_access_message_done(incoming_access_pdu_decrypted);
435         return;
436     }
437     mesh_transport_key_and_virtual_address_iterator_next(&mesh_transport_key_it);
438     const mesh_transport_key_t * message_key = mesh_transport_key_it.key;
439 
440     if (message_key->akf){
441         transport_segmented_setup_application_nonce(application_nonce, (mesh_pdu_t *) incoming_access_pdu_encrypted);
442     } else {
443         transport_segmented_setup_device_nonce(application_nonce, (mesh_pdu_t *) incoming_access_pdu_encrypted);
444     }
445 
446     // store application / device key index
447     mesh_print_hex("AppOrDevKey", message_key->key, 16);
448     incoming_access_pdu_decrypted->appkey_index = message_key->appkey_index;
449 
450     mesh_print_hex("EncAccessPayload", upper_transport_pdu_data, upper_transport_pdu_len);
451 
452     // decrypt ccm
453     crypto_active = 1;
454     uint16_t aad_len  = 0;
455     if (mesh_network_address_virtual(mesh_access_dst(incoming_access_pdu_decrypted))){
456         aad_len  = 16;
457     }
458     btstack_crypto_ccm_init(&ccm, message_key->key, application_nonce, upper_transport_pdu_len, aad_len, incoming_access_pdu_decrypted->transmic_len);
459 
460     if (aad_len){
461         btstack_crypto_ccm_digest(&ccm, (uint8_t *) mesh_transport_key_it.address->label_uuid, aad_len, &mesh_upper_transport_validate_segmented_message_digest, NULL);
462     } else {
463         mesh_upper_transport_validate_segmented_message_digest(NULL);
464     }
465 }
466 
467 static void mesh_upper_transport_process_segmented_message(void){
468     // copy original pdu
469     (void)memcpy(incoming_access_pdu_decrypted, incoming_access_pdu_encrypted,
470                  sizeof(mesh_access_pdu_t));
471 
472     //
473     uint8_t * upper_transport_pdu     =  incoming_access_pdu_decrypted->data;
474     uint8_t   upper_transport_pdu_len = incoming_access_pdu_decrypted->len - incoming_access_pdu_decrypted->transmic_len;
475     mesh_print_hex("Upper Transport pdu", upper_transport_pdu, upper_transport_pdu_len);
476 
477     uint8_t aid = incoming_access_pdu_decrypted->akf_aid_control & 0x3f;
478     uint8_t akf = (incoming_access_pdu_decrypted->akf_aid_control & 0x40) >> 6;
479 
480     printf("AKF: %u\n",   akf);
481     printf("AID: %02x\n", aid);
482 
483     mesh_transport_key_and_virtual_address_iterator_init(&mesh_transport_key_it, mesh_access_dst(incoming_access_pdu_decrypted),
484                                                          incoming_access_pdu_decrypted->netkey_index, akf, aid);
485     mesh_upper_transport_validate_segmented_message();
486 }
487 
488 static void mesh_upper_transport_message_received(mesh_pdu_t * pdu){
489     btstack_linked_list_add_tail(&upper_transport_incoming, (btstack_linked_item_t*) pdu);
490     mesh_upper_transport_run();
491 }
492 
493 static void mesh_upper_transport_send_access_segmented(mesh_upper_transport_pdu_t * upper_pdu){
494 
495     mesh_segmented_pdu_t * message_pdu   = &outgoing_segmented_pdu_singleton;
496     message_pdu->pdu_header.pdu_type = MESH_PDU_TYPE_SEGMENTED;
497 
498     // convert mesh_access_pdu_t into mesh_segmented_pdu_t
499     mesh_segmented_append_payload(crypto_buffer, upper_pdu->len, &message_pdu->segments);
500 
501     // copy meta
502     message_pdu->len = upper_pdu->len;
503     message_pdu->netkey_index = upper_pdu->netkey_index;
504     message_pdu->transmic_len = upper_pdu->transmic_len;
505     message_pdu->akf_aid_control = upper_pdu->akf_aid_control;
506     message_pdu->flags = upper_pdu->flags;
507 
508     // setup message_pdu header
509     // (void)memcpy(message_pdu->network_header, upper_pdu->network_header, 9);
510     // TODO: use fields in mesh_segmented_pdu_t and setup network header in lower transport
511     message_pdu->network_header[0] = upper_pdu->ivi_nid;
512     message_pdu->network_header[1] = upper_pdu->ctl_ttl;
513     big_endian_store_24(message_pdu->network_header, 2, upper_pdu->seq);
514     big_endian_store_16(message_pdu->network_header, 5, upper_pdu->src);
515     big_endian_store_16(message_pdu->network_header, 7, upper_pdu->dst);
516 
517     // queue up
518     upper_pdu->lower_pdu = (mesh_pdu_t *) message_pdu;
519     btstack_linked_list_add(&upper_transport_outgoing_active, (btstack_linked_item_t *) upper_pdu);
520 
521     mesh_lower_transport_send_pdu((mesh_pdu_t*) message_pdu);
522 }
523 
524 static void mesh_upper_transport_send_access_unsegmented(mesh_upper_transport_pdu_t * upper_pdu){
525 
526     // provide segment
527     mesh_network_pdu_t * network_pdu = (mesh_network_pdu_t *) upper_pdu->lower_pdu;
528 
529     // setup network pdu
530     network_pdu->pdu_header.pdu_type = MESH_PDU_TYPE_UPPER_UNSEGMENTED_ACCESS;
531     network_pdu->data[0] = upper_pdu->ivi_nid;
532     network_pdu->data[1] = upper_pdu->ctl_ttl;
533     big_endian_store_24(network_pdu->data, 2, upper_pdu->seq);
534     big_endian_store_16(network_pdu->data, 5, upper_pdu->src);
535     big_endian_store_16(network_pdu->data, 7, upper_pdu->dst);
536     network_pdu->netkey_index = upper_pdu->netkey_index;
537 
538     // setup access message
539     network_pdu->data[9] = upper_pdu->akf_aid_control;
540     btstack_assert(upper_pdu->len < 15);
541     (void)memcpy(&network_pdu->data[10], crypto_buffer, upper_pdu->len);
542     network_pdu->len = 10 + upper_pdu->len;
543     network_pdu->flags = 0;
544 
545     // queue up
546     btstack_linked_list_add(&upper_transport_outgoing_active, (btstack_linked_item_t *) upper_pdu);
547 
548     mesh_lower_transport_send_pdu((mesh_pdu_t*) network_pdu);
549 }
550 
551 static void mesh_upper_transport_send_access_ccm(void * arg){
552     crypto_active = 0;
553 
554     mesh_upper_transport_pdu_t * upper_pdu = (mesh_upper_transport_pdu_t *) arg;
555     mesh_print_hex("EncAccessPayload", crypto_buffer, upper_pdu->len);
556     // store TransMIC
557     btstack_crypto_ccm_get_authentication_value(&ccm, &crypto_buffer[upper_pdu->len]);
558     mesh_print_hex("TransMIC", &crypto_buffer[upper_pdu->len], upper_pdu->transmic_len);
559     upper_pdu->len += upper_pdu->transmic_len;
560     mesh_print_hex("UpperTransportPDU", crypto_buffer, upper_pdu->len);
561     switch (upper_pdu->pdu_header.pdu_type){
562         case MESH_PDU_TYPE_UPPER_UNSEGMENTED_ACCESS:
563             mesh_upper_transport_send_access_unsegmented(upper_pdu);
564             break;
565         case MESH_PDU_TYPE_UPPER_SEGMENTED_ACCESS:
566             mesh_upper_transport_send_access_segmented(upper_pdu);
567             break;
568         default:
569             btstack_assert(false);
570     }
571 }
572 
573 static void mesh_upper_transport_send_access_digest(void *arg){
574     mesh_upper_transport_pdu_t * upper_pdu = (mesh_upper_transport_pdu_t *) arg;
575     uint16_t  access_pdu_len  = upper_pdu->len;
576     btstack_crypto_ccm_encrypt_block(&ccm, access_pdu_len, crypto_buffer, crypto_buffer,
577                                      &mesh_upper_transport_send_access_ccm, upper_pdu);
578 }
579 
580 static void mesh_upper_transport_send_access(mesh_upper_transport_pdu_t * upper_pdu){
581 
582     // if dst is virtual address, lookup label uuid and hash
583     uint16_t aad_len = 0;
584     mesh_virtual_address_t * virtual_address = NULL;
585     if (mesh_network_address_virtual(upper_pdu->dst)){
586         virtual_address = mesh_virtual_address_for_pseudo_dst(upper_pdu->dst);
587         if (!virtual_address){
588             printf("No virtual address register for pseudo dst %4x\n", upper_pdu->dst);
589             mesh_access_message_handler(MESH_TRANSPORT_PDU_SENT, MESH_TRANSPORT_STATUS_SEND_FAILED, (mesh_pdu_t *) upper_pdu);
590             return;
591         }
592         // printf("Using hash %4x with LabelUUID: ", virtual_address->hash);
593         // printf_hexdump(virtual_address->label_uuid, 16);
594         aad_len = 16;
595         upper_pdu->dst = virtual_address->hash;
596     }
597 
598     // get app or device key
599     uint16_t appkey_index = upper_pdu->appkey_index;
600     const mesh_transport_key_t * appkey = mesh_upper_transport_get_outgoing_appkey(upper_pdu->netkey_index, appkey_index);
601     if (appkey == NULL){
602         printf("AppKey %04x not found, drop message\n", appkey_index);
603         mesh_access_message_handler(MESH_TRANSPORT_PDU_SENT, MESH_TRANSPORT_STATUS_SEND_FAILED, (mesh_pdu_t *) upper_pdu);
604         return;
605     }
606 
607     // reserve slot
608     mesh_lower_transport_reserve_slot();
609 
610     // reserve one sequence number, which is also used to encrypt access payload
611     uint32_t seq = mesh_sequence_number_next();
612     upper_pdu->flags |= MESH_TRANSPORT_FLAG_SEQ_RESERVED;
613     upper_pdu->seq = seq;
614 
615     // also reserves crypto_buffer
616     crypto_active = 1;
617 
618     // flatten segmented pdu into crypto buffer
619     uint16_t payload_len = mesh_upper_pdu_flatten(upper_pdu, crypto_buffer, sizeof(crypto_buffer));
620     btstack_assert(payload_len == upper_pdu->len);
621 
622     // Dump PDU
623     printf("[+] Upper transport, send upper (un)segmented Access PDU - dest %04x, seq %06x\n", upper_pdu->dst, upper_pdu->seq);
624     mesh_print_hex("Access Payload", crypto_buffer, upper_pdu->len);
625 
626     // setup nonce - uses dst, so after pseudo address translation
627     if (appkey_index == MESH_DEVICE_KEY_INDEX){
628         transport_segmented_setup_device_nonce(application_nonce, (mesh_pdu_t *) upper_pdu);
629     } else {
630         transport_segmented_setup_application_nonce(application_nonce, (mesh_pdu_t *) upper_pdu);
631     }
632 
633     // Dump key
634     mesh_print_hex("AppOrDevKey", appkey->key, 16);
635 
636     // encrypt ccm
637     uint8_t   transmic_len    = upper_pdu->transmic_len;
638     uint16_t  access_pdu_len  = upper_pdu->len;
639     btstack_crypto_ccm_init(&ccm, appkey->key, application_nonce, access_pdu_len, aad_len, transmic_len);
640     if (virtual_address){
641         mesh_print_hex("LabelUUID", virtual_address->label_uuid, 16);
642         btstack_crypto_ccm_digest(&ccm, virtual_address->label_uuid, 16,
643                                   &mesh_upper_transport_send_access_digest, upper_pdu);
644     } else {
645         mesh_upper_transport_send_access_digest(upper_pdu);
646     }
647 }
648 
649 static void mesh_upper_transport_send_unsegmented_control_pdu(mesh_network_pdu_t * network_pdu){
650     // reserve slot
651     mesh_lower_transport_reserve_slot();
652     // reserve sequence number
653     uint32_t seq = mesh_sequence_number_next();
654     mesh_network_pdu_set_seq(network_pdu, seq);
655     // Dump PDU
656     uint8_t opcode = network_pdu->data[9];
657     printf("[+] Upper transport, send unsegmented Control PDU %p - seq %06x opcode %02x\n", network_pdu, seq, opcode);
658     mesh_print_hex("Access Payload", &network_pdu->data[10], network_pdu->len - 10);
659 
660     // send
661      mesh_lower_transport_send_pdu((mesh_pdu_t *) network_pdu);
662 }
663 
664 static void mesh_upper_transport_send_segmented_control_pdu(mesh_upper_transport_pdu_t * upper_pdu){
665     // reserve slot
666     mesh_lower_transport_reserve_slot();
667     // reserve sequence number
668     uint32_t seq = mesh_sequence_number_next();
669     upper_pdu->flags |= MESH_TRANSPORT_FLAG_SEQ_RESERVED;
670     upper_pdu->seq = seq;
671     // Dump PDU
672     // uint8_t opcode = upper_pdu->data[0];
673     // printf("[+] Upper transport, send segmented Control PDU %p - seq %06x opcode %02x\n", upper_pdu, seq, opcode);
674     // mesh_print_hex("Access Payload", &upper_pdu->data[1], upper_pdu->len - 1);
675     // send
676     mesh_segmented_pdu_t *message_pdu = &outgoing_segmented_pdu_singleton;
677     message_pdu->pdu_header.pdu_type = MESH_PDU_TYPE_SEGMENTED;
678 
679     // lend segments to lower transport pdu
680     message_pdu->segments = upper_pdu->segments;
681     upper_pdu->segments = NULL;
682 
683     // copy meta
684     message_pdu->len = upper_pdu->len;
685     message_pdu->netkey_index = upper_pdu->netkey_index;
686     message_pdu->transmic_len = 0;   // no TransMIC for control
687     message_pdu->akf_aid_control = upper_pdu->akf_aid_control;
688     message_pdu->flags = upper_pdu->flags;
689 
690     // setup message_pdu header
691     // TODO: use fields in mesh_segmented_pdu_t and setup network header in lower transport
692     message_pdu->network_header[0] = upper_pdu->ivi_nid;
693     message_pdu->network_header[1] = upper_pdu->ctl_ttl;
694     big_endian_store_24(message_pdu->network_header, 2, upper_pdu->seq);
695     big_endian_store_16(message_pdu->network_header, 5, upper_pdu->src);
696     big_endian_store_16(message_pdu->network_header, 7, upper_pdu->dst);
697 
698     // queue up
699     upper_pdu->lower_pdu = (mesh_pdu_t *) message_pdu;
700     btstack_linked_list_add(&upper_transport_outgoing_active, (btstack_linked_item_t *) upper_pdu);
701 
702     mesh_lower_transport_send_pdu((mesh_pdu_t *) message_pdu);
703 }
704 
705 static void mesh_upper_transport_run(void){
706 
707     while(!btstack_linked_list_empty(&upper_transport_incoming)){
708 
709         if (crypto_active) return;
710 
711         // get next message
712         mesh_pdu_t * pdu =  (mesh_pdu_t *) btstack_linked_list_pop(&upper_transport_incoming);
713         mesh_network_pdu_t   * network_pdu;
714         mesh_segmented_pdu_t   * message_pdu;
715         switch (pdu->pdu_type){
716             case MESH_PDU_TYPE_UNSEGMENTED:
717                 network_pdu = (mesh_network_pdu_t *) pdu;
718                 // control?
719                 if (mesh_network_control(network_pdu)) {
720 
721                     incoming_control_pdu =  &incoming_control_pdu_singleton;
722                     incoming_control_pdu->pdu_header.pdu_type = MESH_PDU_TYPE_CONTROL;
723                     incoming_control_pdu->len =  network_pdu->len;
724                     incoming_control_pdu->netkey_index =  network_pdu->netkey_index;
725 
726                     uint8_t * lower_transport_pdu = mesh_network_pdu_data(network_pdu);
727 
728                     incoming_control_pdu->akf_aid_control = lower_transport_pdu[0];
729                     incoming_control_pdu->len = network_pdu->len - 10; // 9 header + 1 opcode
730                     (void)memcpy(incoming_control_pdu->data, &lower_transport_pdu[1], incoming_control_pdu->len);
731 
732                     // copy meta data into encrypted pdu buffer
733                     (void)memcpy(incoming_control_pdu->network_header, network_pdu->data, 9);
734 
735                     mesh_print_hex("Assembled payload", incoming_control_pdu->data, incoming_control_pdu->len);
736 
737                     // free mesh message
738                     mesh_lower_transport_message_processed_by_higher_layer(pdu);
739 
740                     btstack_assert(mesh_control_message_handler != NULL);
741                     mesh_pdu_t * pdu = (mesh_pdu_t*) incoming_control_pdu;
742                     mesh_control_message_handler(MESH_TRANSPORT_PDU_RECEIVED, MESH_TRANSPORT_STATUS_SUCCESS, pdu);
743 
744                 } else {
745 
746                     incoming_access_pdu_encrypted = &incoming_access_pdu_encrypted_singleton;
747                     incoming_access_pdu_encrypted->pdu_header.pdu_type = MESH_PDU_TYPE_ACCESS;
748                     incoming_access_pdu_decrypted = &incoming_access_pdu_decrypted_singleton;
749 
750                     incoming_access_pdu_encrypted->netkey_index = network_pdu->netkey_index;
751                     incoming_access_pdu_encrypted->transmic_len = 4;
752 
753                     uint8_t * lower_transport_pdu = mesh_network_pdu_data(network_pdu);
754 
755                     incoming_access_pdu_encrypted->akf_aid_control = lower_transport_pdu[0];
756                     incoming_access_pdu_encrypted->len = network_pdu->len - 10; // 9 header + 1 AID
757                     (void)memcpy(incoming_access_pdu_encrypted->data, &lower_transport_pdu[1], incoming_access_pdu_encrypted->len);
758 
759                     // copy meta data into encrypted pdu buffer
760                     (void)memcpy(incoming_access_pdu_encrypted->network_header, network_pdu->data, 9);
761 
762                     mesh_print_hex("Assembled payload", incoming_access_pdu_encrypted->data, incoming_access_pdu_encrypted->len);
763 
764                     // free mesh message
765                     mesh_lower_transport_message_processed_by_higher_layer(pdu);
766 
767                     // get encoded transport pdu and start processing
768                     mesh_upper_transport_process_segmented_message();
769                 }
770                 break;
771             case MESH_PDU_TYPE_SEGMENTED:
772                 message_pdu = (mesh_segmented_pdu_t *) pdu;
773                 uint8_t ctl = mesh_message_ctl(message_pdu);
774                 if (ctl){
775                     incoming_control_pdu=  &incoming_control_pdu_singleton;
776                     incoming_control_pdu->pdu_header.pdu_type = MESH_PDU_TYPE_CONTROL;
777 
778                     // flatten
779                     mesh_segmented_pdu_flatten(&message_pdu->segments, 8, incoming_control_pdu->data);
780 
781                     // copy meta data into encrypted pdu buffer
782                     incoming_control_pdu->len =  message_pdu->len;
783                     incoming_control_pdu->netkey_index =  message_pdu->netkey_index;
784                     incoming_control_pdu->akf_aid_control =  message_pdu->akf_aid_control;
785                     incoming_control_pdu->flags = 0;
786                     (void)memcpy(incoming_control_pdu->network_header, message_pdu->network_header, 9);
787 
788                     mesh_print_hex("Assembled payload", incoming_control_pdu->data, incoming_control_pdu->len);
789 
790                     // free mesh message
791                     mesh_lower_transport_message_processed_by_higher_layer((mesh_pdu_t *)message_pdu);
792 
793                     btstack_assert(mesh_control_message_handler != NULL);
794                     mesh_pdu_t * pdu = (mesh_pdu_t*) incoming_control_pdu;
795                     mesh_access_message_handler(MESH_TRANSPORT_PDU_RECEIVED, MESH_TRANSPORT_STATUS_SUCCESS, pdu);
796 
797                 } else {
798 
799                     incoming_access_pdu_encrypted = &incoming_access_pdu_encrypted_singleton;
800                     incoming_access_pdu_encrypted->pdu_header.pdu_type = MESH_PDU_TYPE_ACCESS;
801                     incoming_access_pdu_decrypted = &incoming_access_pdu_decrypted_singleton;
802 
803                     // flatten
804                     mesh_segmented_pdu_flatten(&message_pdu->segments, 12, incoming_access_pdu_encrypted->data);
805 
806                     // copy meta data into encrypted pdu buffer
807                     incoming_access_pdu_encrypted->len =  message_pdu->len;
808                     incoming_access_pdu_encrypted->netkey_index =  message_pdu->netkey_index;
809                     incoming_access_pdu_encrypted->transmic_len =  message_pdu->transmic_len;
810                     incoming_access_pdu_encrypted->akf_aid_control =  message_pdu->akf_aid_control;
811                     (void)memcpy(incoming_access_pdu_encrypted->network_header, message_pdu->network_header, 9);
812 
813                     mesh_print_hex("Assembled payload", incoming_access_pdu_encrypted->data, incoming_access_pdu_encrypted->len);
814 
815                     // free mesh message
816                     mesh_lower_transport_message_processed_by_higher_layer((mesh_pdu_t *)message_pdu);
817 
818                     // get encoded transport pdu and start processing
819                     mesh_upper_transport_process_segmented_message();
820                 }
821                 break;
822             default:
823                 btstack_assert(0);
824                 break;
825         }
826     }
827 
828     while (!btstack_linked_list_empty(&upper_transport_outgoing)){
829 
830         if (crypto_active) break;
831 
832         mesh_pdu_t * pdu =  (mesh_pdu_t *) btstack_linked_list_get_first_item(&upper_transport_outgoing);
833         if (mesh_lower_transport_can_send_to_dest(mesh_pdu_dst(pdu)) == 0) break;
834 
835         mesh_upper_transport_pdu_t * upper_pdu;
836 
837         switch (pdu->pdu_type){
838             case MESH_PDU_TYPE_UPPER_UNSEGMENTED_CONTROL:
839                 // control pdus can go through directly
840                 btstack_assert(mesh_pdu_ctl(pdu) != 0);
841                 (void) btstack_linked_list_pop(&upper_transport_outgoing);
842                 mesh_upper_transport_send_unsegmented_control_pdu((mesh_network_pdu_t *) pdu);
843                 break;
844             case MESH_PDU_TYPE_UPPER_SEGMENTED_CONTROL:
845                 // control pdus can go through directly
846                 btstack_assert(mesh_pdu_ctl(pdu) != 0);
847                 (void) btstack_linked_list_pop(&upper_transport_outgoing);
848                 mesh_upper_transport_send_segmented_control_pdu((mesh_upper_transport_pdu_t *) pdu);
849                 break;
850             case MESH_PDU_TYPE_UPPER_SEGMENTED_ACCESS:
851                 // segmented access pdus required a mesh-segmented-pdu
852                 if (upper_transport_outgoing_segmented == NULL){
853                     upper_transport_outgoing_segmented = btstack_memory_mesh_segmented_pdu_get();
854                 }
855                 if (upper_transport_outgoing_segmented == NULL) break;
856                 upper_transport_outgoing_segmented->pdu_header.pdu_type = MESH_PDU_TYPE_SEGMENTED;
857                 // and a mesh-network-pdu for each segments
858                 // TODO: reserve segments
859                 (void) btstack_linked_list_pop(&upper_transport_outgoing);
860                 mesh_upper_transport_send_access((mesh_upper_transport_pdu_t *) pdu);
861                 break;
862             case MESH_PDU_TYPE_UPPER_UNSEGMENTED_ACCESS:
863                 // unsegmented access pdus require a single mesh-network-dpu
864                 upper_pdu = (mesh_upper_transport_pdu_t *) pdu;
865                 if (upper_pdu->lower_pdu == NULL){
866                     upper_pdu->lower_pdu = (mesh_pdu_t *) mesh_network_pdu_get();
867                 }
868                 if (upper_pdu->lower_pdu == NULL) break;
869                 (void) btstack_linked_list_pop(&upper_transport_outgoing);
870                 mesh_upper_transport_send_access((mesh_upper_transport_pdu_t *) pdu);
871                 break;
872             default:
873                 btstack_assert(false);
874                 break;
875         }
876     }
877 }
878 
879 static mesh_upper_transport_pdu_t * mesh_upper_transport_find_pdu_for_lower(mesh_pdu_t * pdu_to_find){
880     btstack_linked_list_iterator_t it;
881     btstack_linked_list_iterator_init(&it, &upper_transport_outgoing_active);
882     mesh_upper_transport_pdu_t * upper_pdu;
883     while (btstack_linked_list_iterator_has_next(&it)){
884         mesh_pdu_t * mesh_pdu = (mesh_pdu_t *) btstack_linked_list_iterator_next(&it);
885         switch (mesh_pdu->pdu_type){
886             case MESH_PDU_TYPE_UPPER_SEGMENTED_CONTROL:
887             case MESH_PDU_TYPE_UPPER_UNSEGMENTED_ACCESS:
888             case MESH_PDU_TYPE_UPPER_SEGMENTED_ACCESS:
889                 upper_pdu = (mesh_upper_transport_pdu_t *) mesh_pdu;
890                 if (upper_pdu->lower_pdu == pdu_to_find){
891                     btstack_linked_list_iterator_remove(&it);
892                     return upper_pdu;
893                 }
894                 break;
895             default:
896                 break;
897         }
898     }
899     return NULL;
900 }
901 
902 static void mesh_upper_transport_pdu_handler(mesh_transport_callback_type_t callback_type, mesh_transport_status_t status, mesh_pdu_t * pdu){
903     mesh_upper_transport_pdu_t * upper_pdu;
904     mesh_network_pdu_t * network_pdu;
905     mesh_segmented_pdu_t * segmented_pdu;
906     switch (callback_type){
907         case MESH_TRANSPORT_PDU_RECEIVED:
908             mesh_upper_transport_message_received(pdu);
909             break;
910         case MESH_TRANSPORT_PDU_SENT:
911             switch (pdu->pdu_type){
912                 case MESH_PDU_TYPE_SEGMENTED:
913                     // try to find in outgoing active
914                     upper_pdu = mesh_upper_transport_find_pdu_for_lower(pdu);
915                     btstack_assert(upper_pdu != NULL);
916                     segmented_pdu = (mesh_segmented_pdu_t *) pdu;
917                     // free chunks
918                     while (!btstack_linked_list_empty(&segmented_pdu->segments)){
919                         mesh_network_pdu_t * network_pdu = (mesh_network_pdu_t *) btstack_linked_list_pop(&segmented_pdu->segments);
920                         mesh_network_pdu_free(network_pdu);
921                     }
922                     // TODO: free segmented_pdu
923                     upper_pdu->lower_pdu = NULL;
924                     switch (upper_pdu->pdu_header.pdu_type){
925                         case MESH_PDU_TYPE_UPPER_SEGMENTED_CONTROL:
926                             mesh_control_message_handler(callback_type, status, (mesh_pdu_t *) upper_pdu);
927                             break;
928                         case MESH_PDU_TYPE_UPPER_SEGMENTED_ACCESS:
929                             mesh_access_message_handler(callback_type, status, (mesh_pdu_t *) upper_pdu);
930                             break;
931                         default:
932                             btstack_assert(false);
933                             break;
934                     }
935                     break;
936                 case MESH_PDU_TYPE_UPPER_UNSEGMENTED_ACCESS:
937                     // find corresponding upper transport pdu and free single segment
938                     upper_pdu = mesh_upper_transport_find_pdu_for_lower(pdu);
939                     btstack_assert(upper_pdu != NULL);
940                     btstack_assert(upper_pdu->lower_pdu == (mesh_pdu_t *) pdu);
941                     mesh_network_pdu_free((mesh_network_pdu_t *) pdu);
942                     upper_pdu->lower_pdu = NULL;
943                     mesh_access_message_handler(callback_type, status, (mesh_pdu_t*) upper_pdu);
944                     break;
945                 case MESH_PDU_TYPE_UPPER_UNSEGMENTED_CONTROL:
946                     mesh_access_message_handler(callback_type, status, pdu);
947                     break;
948                 default:
949                     btstack_assert(false);
950                     break;
951             }
952             mesh_upper_transport_run();
953             break;
954         default:
955             break;
956     }
957 }
958 
959 void mesh_upper_transport_pdu_free(mesh_pdu_t * pdu){
960     mesh_network_pdu_t   * network_pdu;
961     mesh_segmented_pdu_t   * message_pdu;
962     switch (pdu->pdu_type) {
963         case MESH_PDU_TYPE_NETWORK:
964             network_pdu = (mesh_network_pdu_t *) pdu;
965             mesh_network_pdu_free(network_pdu);
966             break;
967         case MESH_PDU_TYPE_SEGMENTED:
968             message_pdu = (mesh_segmented_pdu_t *) pdu;
969             mesh_message_pdu_free(message_pdu);
970         default:
971             btstack_assert(false);
972             break;
973     }
974 }
975 
976 void mesh_upper_transport_message_processed_by_higher_layer(mesh_pdu_t * pdu){
977     crypto_active = 0;
978     switch (pdu->pdu_type){
979         case MESH_PDU_TYPE_ACCESS:
980             mesh_upper_transport_process_access_message_done((mesh_access_pdu_t *) pdu);
981         case MESH_PDU_TYPE_CONTROL:
982             mesh_upper_transport_process_control_message_done((mesh_control_pdu_t *) pdu);
983             break;
984         default:
985             btstack_assert(0);
986             break;
987     }
988 }
989 
990 void mesh_upper_transport_send_access_pdu(mesh_pdu_t *pdu){
991     switch (pdu->pdu_type){
992         case MESH_PDU_TYPE_UPPER_SEGMENTED_ACCESS:
993         case MESH_PDU_TYPE_UPPER_UNSEGMENTED_ACCESS:
994             break;
995         default:
996             btstack_assert(false);
997             break;
998     }
999 
1000     btstack_assert(((mesh_upper_transport_pdu_t *) pdu)->lower_pdu == NULL);
1001 
1002     btstack_linked_list_add_tail(&upper_transport_outgoing, (btstack_linked_item_t*) pdu);
1003     mesh_upper_transport_run();
1004 }
1005 
1006 void mesh_upper_transport_send_control_pdu(mesh_pdu_t * pdu){
1007     switch (pdu->pdu_type){
1008         case MESH_PDU_TYPE_UPPER_SEGMENTED_CONTROL:
1009             break;
1010         case MESH_PDU_TYPE_UPPER_UNSEGMENTED_CONTROL:
1011             btstack_assert( ((mesh_network_pdu_t *) pdu)->len >= 9);
1012             break;
1013         default:
1014             btstack_assert(false);
1015             break;
1016     }
1017 
1018     btstack_linked_list_add_tail(&upper_transport_outgoing, (btstack_linked_item_t*) pdu);
1019     mesh_upper_transport_run();
1020 }
1021 
1022 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,
1023                                                                   const uint8_t * control_pdu_data, uint16_t control_pdu_len){
1024 
1025     if (control_pdu_len > 11) return 1;
1026 
1027     const mesh_network_key_t * network_key = mesh_network_key_list_get(netkey_index);
1028     if (!network_key) return 1;
1029 
1030     uint8_t transport_pdu_data[12];
1031     transport_pdu_data[0] = opcode;
1032     (void)memcpy(&transport_pdu_data[1], control_pdu_data, control_pdu_len);
1033     uint16_t transport_pdu_len = control_pdu_len + 1;
1034 
1035     // setup network_pdu
1036     mesh_network_setup_pdu(network_pdu, netkey_index, network_key->nid, 1, ttl, 0, src, dest, transport_pdu_data, transport_pdu_len);
1037 
1038     return 0;
1039 }
1040 
1041 static uint8_t mesh_upper_transport_setup_segmented_control_pdu(mesh_upper_transport_pdu_t * upper_pdu, uint16_t netkey_index, uint8_t ttl, uint16_t src, uint16_t dest, uint8_t opcode,
1042                                                                 const uint8_t * control_pdu_data, uint16_t control_pdu_len){
1043 
1044     if (control_pdu_len > 256) return 1;
1045 
1046     const mesh_network_key_t * network_key = mesh_network_key_list_get(netkey_index);
1047     if (!network_key) return 1;
1048 
1049     upper_pdu->ivi_nid = network_key->nid | ((mesh_get_iv_index_for_tx() & 1) << 7);
1050     upper_pdu->ctl_ttl = ttl;
1051     upper_pdu->src = src;
1052     upper_pdu->dst = dest;
1053     upper_pdu->transmic_len = 0;    // no TransMIC for control
1054     upper_pdu->netkey_index = netkey_index;
1055     upper_pdu->akf_aid_control = opcode;
1056 
1057     mesh_segmented_append_payload(control_pdu_data, control_pdu_len, &upper_pdu->segments);
1058     upper_pdu->len = control_pdu_len;
1059     return 0;
1060 }
1061 
1062 uint8_t mesh_upper_transport_setup_control_pdu(mesh_pdu_t * pdu, uint16_t netkey_index,
1063                                                uint8_t ttl, uint16_t src, uint16_t dest, uint8_t opcode, const uint8_t * control_pdu_data, uint16_t control_pdu_len){
1064     switch (pdu->pdu_type){
1065         case MESH_PDU_TYPE_UPPER_UNSEGMENTED_CONTROL:
1066             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);
1067         case MESH_PDU_TYPE_UPPER_SEGMENTED_CONTROL:
1068             return mesh_upper_transport_setup_segmented_control_pdu((mesh_upper_transport_pdu_t *) pdu,  netkey_index, ttl, src, dest, opcode, control_pdu_data, control_pdu_len);
1069         default:
1070             btstack_assert(0);
1071             return 1;
1072     }
1073 }
1074 
1075 static uint8_t mesh_upper_transport_setup_segmented_access_pdu_header(mesh_access_pdu_t * access_pdu, uint16_t netkey_index,
1076                                                                       uint16_t appkey_index, uint8_t ttl, uint16_t src, uint16_t dest, uint8_t szmic){
1077 
1078     // get app or device key
1079     const mesh_transport_key_t *appkey;
1080     appkey = mesh_transport_key_get(appkey_index);
1081     if (appkey == NULL) {
1082         printf("[!] Upper transport, setup segmented Access PDU - appkey_index %x unknown\n", appkey_index);
1083         return 1;
1084     }
1085     uint8_t akf_aid = (appkey->akf << 6) | appkey->aid;
1086 
1087     // lookup network by netkey_index
1088     const mesh_network_key_t *network_key = mesh_network_key_list_get(netkey_index);
1089     if (!network_key) return 1;
1090     if (network_key == NULL) {
1091         printf("[!] Upper transport, setup segmented Access PDU - netkey_index %x unknown\n", appkey_index);
1092         return 1;
1093     }
1094 
1095     const uint8_t trans_mic_len = szmic ? 8 : 4;
1096 
1097     // store in transport pdu
1098     access_pdu->transmic_len = trans_mic_len;
1099     access_pdu->netkey_index = netkey_index;
1100     access_pdu->appkey_index = appkey_index;
1101     access_pdu->akf_aid_control = akf_aid;
1102     mesh_access_set_nid_ivi(access_pdu, network_key->nid | ((mesh_get_iv_index_for_tx() & 1) << 7));
1103     mesh_access_set_src(access_pdu, src);
1104     mesh_access_set_dest(access_pdu, dest);
1105     mesh_access_set_ctl_ttl(access_pdu, ttl);
1106     return 0;
1107 }
1108 
1109 static uint8_t mesh_upper_transport_setup_upper_access_pdu_header(mesh_upper_transport_pdu_t * upper_pdu, uint16_t netkey_index,
1110                                                                   uint16_t appkey_index, uint8_t ttl, uint16_t src, uint16_t dest, uint8_t szmic){
1111 
1112     // get app or device key
1113     const mesh_transport_key_t *appkey;
1114     appkey = mesh_transport_key_get(appkey_index);
1115     if (appkey == NULL) {
1116         printf("[!] Upper transport, setup segmented Access PDU - appkey_index %x unknown\n", appkey_index);
1117         return 1;
1118     }
1119     uint8_t akf_aid = (appkey->akf << 6) | appkey->aid;
1120 
1121     // lookup network by netkey_index
1122     const mesh_network_key_t *network_key = mesh_network_key_list_get(netkey_index);
1123     if (!network_key) return 1;
1124     if (network_key == NULL) {
1125         printf("[!] Upper transport, setup segmented Access PDU - netkey_index %x unknown\n", appkey_index);
1126         return 1;
1127     }
1128 
1129     const uint8_t trans_mic_len = szmic ? 8 : 4;
1130 
1131     // store in transport pdu
1132     upper_pdu->ivi_nid = network_key->nid | ((mesh_get_iv_index_for_tx() & 1) << 7);
1133     upper_pdu->ctl_ttl = ttl;
1134     upper_pdu->src = src;
1135     upper_pdu->dst = dest;
1136     upper_pdu->transmic_len = trans_mic_len;
1137     upper_pdu->netkey_index = netkey_index;
1138     upper_pdu->appkey_index = appkey_index;
1139     upper_pdu->akf_aid_control = akf_aid;
1140     return 0;
1141 }
1142 
1143 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,
1144                                                            uint8_t szmic, const uint8_t * access_pdu_data, uint8_t access_pdu_len){
1145     int status = mesh_upper_transport_setup_upper_access_pdu_header(upper_pdu, netkey_index, appkey_index, ttl, src,
1146                                                                     dest, szmic);
1147     if (status) return status;
1148 
1149     // store in transport pdu
1150     mesh_segmented_append_payload(access_pdu_data, access_pdu_len, &upper_pdu->segments);
1151     upper_pdu->len = access_pdu_len;
1152     return 0;
1153 }
1154 
1155 
1156 uint8_t mesh_upper_transport_setup_access_pdu_header(mesh_pdu_t * pdu, uint16_t netkey_index, uint16_t appkey_index,
1157                                                      uint8_t ttl, uint16_t src, uint16_t dest, uint8_t szmic){
1158     switch (pdu->pdu_type){
1159         case MESH_PDU_TYPE_ACCESS:
1160             return mesh_upper_transport_setup_segmented_access_pdu_header((mesh_access_pdu_t *) pdu, netkey_index, appkey_index, ttl, src, dest, szmic);
1161         default:
1162             btstack_assert(false);
1163             return 1;
1164     }
1165 }
1166 
1167 uint8_t mesh_upper_transport_setup_access_pdu(mesh_pdu_t * pdu, uint16_t netkey_index, uint16_t appkey_index,
1168                                               uint8_t ttl, uint16_t src, uint16_t dest, uint8_t szmic,
1169                                               const uint8_t * access_pdu_data, uint8_t access_pdu_len){
1170     switch (pdu->pdu_type){
1171         case MESH_PDU_TYPE_UPPER_SEGMENTED_ACCESS:
1172         case MESH_PDU_TYPE_UPPER_UNSEGMENTED_ACCESS:
1173             return mesh_upper_transport_setup_upper_access_pdu((mesh_upper_transport_pdu_t *) pdu, netkey_index,
1174                                                                appkey_index, ttl, src, dest, szmic, access_pdu_data,
1175                                                                access_pdu_len);
1176         default:
1177             btstack_assert(false);
1178             return 1;
1179     }
1180 }
1181 
1182 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)) {
1183     mesh_access_message_handler = callback;
1184 }
1185 
1186 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)){
1187     mesh_control_message_handler = callback;
1188 }
1189 
1190 void mesh_upper_transport_init(){
1191     mesh_lower_transport_set_higher_layer_handler(&mesh_upper_transport_pdu_handler);
1192 }
1193