xref: /btstack/src/mesh/mesh_upper_transport.c (revision 6f6f8b16b187b6f853cd67c766447d952356c78d)
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 #include <stdarg.h>
39 #include "btstack_tlv.h"
40 #include "mesh/mesh_foundation.h"
41 #include "mesh_upper_transport.h"
42 #include "mesh/mesh.h"
43 #include "mesh/mesh_proxy.h"
44 #include "mesh/mesh_node.h"
45 
46 #define BTSTACK_FILE__ "mesh_upper_transport.c"
47 
48 #include "mesh/mesh_upper_transport.h"
49 
50 #include <stdio.h>
51 #include <stdlib.h>
52 #include <string.h>
53 
54 #include "btstack_util.h"
55 #include "btstack_memory.h"
56 #include "btstack_debug.h"
57 #include "btstack_bool.h"
58 
59 #include "mesh/beacon.h"
60 #include "mesh/mesh_iv_index_seq_number.h"
61 #include "mesh/mesh_keys.h"
62 #include "mesh/mesh_lower_transport.h"
63 #include "mesh/mesh_peer.h"
64 #include "mesh/mesh_virtual_addresses.h"
65 
66 // TODO: extract mesh_pdu functions into lower transport or network
67 #include "mesh/mesh_access.h"
68 
69 // MESH_ACCESS_MESH_NETWORK_PAYLOAD_MAX (384) / MESH_NETWORK_PAYLOAD_MAX (29) = 13.24.. < 14
70 #define MESSAGE_BUILDER_MAX_NUM_NETWORK_PDUS (14)
71 
72 // combined key x address iterator for upper transport decryption
73 
74 typedef struct {
75     // state
76     mesh_transport_key_iterator_t  key_it;
77     mesh_virtual_address_iterator_t address_it;
78     // elements
79     const mesh_transport_key_t *   key;
80     const mesh_virtual_address_t * address;
81     // address - might be virtual
82     uint16_t dst;
83     // key info
84 } mesh_transport_key_and_virtual_address_iterator_t;
85 
86 static void mesh_upper_transport_run(void);
87 static void mesh_upper_transport_schedule_send_requests(void);
88 static void mesh_upper_transport_validate_access_message(void);
89 
90 // upper transport callbacks - in access layer
91 static void (*mesh_access_message_handler)( mesh_transport_callback_type_t callback_type, mesh_transport_status_t status, mesh_pdu_t * pdu);
92 static void (*mesh_control_message_handler)( mesh_transport_callback_type_t callback_type, mesh_transport_status_t status, mesh_pdu_t * pdu);
93 
94 //
95 static int crypto_active;
96 static uint8_t application_nonce[13];
97 static btstack_crypto_ccm_t ccm;
98 static mesh_transport_key_and_virtual_address_iterator_t mesh_transport_key_it;
99 
100 // incoming segmented (mesh_segmented_pdu_t) or unsegmented (network_pdu_t)
101 static mesh_pdu_t *          incoming_access_encrypted;
102 
103 // multi-purpose union: segmented control reassembly, decrypted access pdu
104 static union {
105     mesh_control_pdu_t    control;
106     mesh_access_pdu_t     access;
107 } incoming_pdu_singleton;
108 
109 // pointer to incoming_pdu_singleton.access
110 static mesh_access_pdu_t *   incoming_access_decrypted;
111 
112 // pointer to incoming_pdu_singleton.access
113 static mesh_control_pdu_t *  incoming_control_pdu;
114 
115 // incoming incoming_access_decrypted ready to be deliverd
116 static bool incoming_access_pdu_ready;
117 
118 // incoming unsegmented (network) and segmented (transport) control and access messages
119 static btstack_linked_list_t upper_transport_incoming;
120 
121 
122 // outgoing unsegmented and segmented control and access messages
123 static btstack_linked_list_t upper_transport_outgoing;
124 
125 // outgoing upper transport messages that have been sent to lower transport and wait for sent event
126 static btstack_linked_list_t upper_transport_outgoing_active;
127 
128 // outgoing send requests
129 static btstack_linked_list_t upper_transport_send_requests;
130 
131 // message builder buffers
132 static mesh_upper_transport_pdu_t * message_builder_reserved_upper_pdu;
133 static uint8_t message_builder_num_network_pdus_reserved;
134 static btstack_linked_list_t message_builder_reserved_network_pdus;
135 
136 // requets network pdus for outgoing send requests and outgoing run
137 static bool upper_transport_need_pdu_for_send_requests;
138 static bool upper_transport_need_pdu_for_run_outgoing;
139 
140 // TODO: higher layer define used for assert
141 #define MESH_ACCESS_OPCODE_NOT_SET 0xFFFFFFFEu
142 
143 static void mesh_print_hex(const char * name, const uint8_t * data, uint16_t len){
144     printf("%-20s ", name);
145     printf_hexdump(data, len);
146 }
147 // static void mesh_print_x(const char * name, uint32_t value){
148 //     printf("%20s: 0x%x", name, (int) value);
149 // }
150 
151 static void mesh_transport_key_and_virtual_address_iterator_init(mesh_transport_key_and_virtual_address_iterator_t *it,
152                                                                  uint16_t dst, uint16_t netkey_index, uint8_t akf,
153                                                                  uint8_t aid) {
154     printf("KEY_INIT: dst %04x, akf %x, aid %x\n", dst, akf, aid);
155     // config
156     it->dst   = dst;
157     // init elements
158     it->key     = NULL;
159     it->address = NULL;
160     // init element iterators
161     mesh_transport_key_aid_iterator_init(&it->key_it, netkey_index, akf, aid);
162     // init address iterator
163     if (mesh_network_address_virtual(it->dst)){
164         mesh_virtual_address_iterator_init(&it->address_it, dst);
165         // get first key
166         if (mesh_transport_key_aid_iterator_has_more(&it->key_it)) {
167             it->key = mesh_transport_key_aid_iterator_get_next(&it->key_it);
168         }
169     }
170 }
171 
172 // cartesian product: keys x addressses
173 static int mesh_transport_key_and_virtual_address_iterator_has_more(mesh_transport_key_and_virtual_address_iterator_t * it){
174     if (mesh_network_address_virtual(it->dst)) {
175         // find next valid entry
176         while (true){
177             if (mesh_virtual_address_iterator_has_more(&it->address_it)) return 1;
178             if (!mesh_transport_key_aid_iterator_has_more(&it->key_it)) return 0;
179             // get next key
180             it->key = mesh_transport_key_aid_iterator_get_next(&it->key_it);
181             mesh_virtual_address_iterator_init(&it->address_it, it->dst);
182         }
183     } else {
184         return mesh_transport_key_aid_iterator_has_more(&it->key_it);
185     }
186 }
187 
188 static void mesh_transport_key_and_virtual_address_iterator_next(mesh_transport_key_and_virtual_address_iterator_t * it){
189     if (mesh_network_address_virtual(it->dst)) {
190         it->address = mesh_virtual_address_iterator_get_next(&it->address_it);
191     } else {
192         it->key = mesh_transport_key_aid_iterator_get_next(&it->key_it);
193     }
194 }
195 
196 // UPPER TRANSPORT
197 
198 static void mesh_segmented_pdu_flatten(btstack_linked_list_t * segments, uint8_t segment_len, uint8_t * buffer) {
199     // assemble payload
200     btstack_linked_list_iterator_t it;
201     btstack_linked_list_iterator_init(&it, segments);
202     while (btstack_linked_list_iterator_has_next(&it)) {
203         mesh_network_pdu_t *segment = (mesh_network_pdu_t *) btstack_linked_list_iterator_next(&it);
204         btstack_assert(segment->pdu_header.pdu_type == MESH_PDU_TYPE_NETWORK);
205         uint8_t offset = 0;
206         while (offset < segment->len){
207             uint8_t seg_o = segment->data[offset++];
208             (void) memcpy(&buffer[seg_o * segment_len], &segment->data[offset], segment_len);
209             offset += segment_len;
210         }
211     }
212 }
213 
214 static uint16_t mesh_upper_pdu_flatten(mesh_upper_transport_pdu_t * upper_pdu, uint8_t * buffer, uint16_t buffer_len) {
215     // assemble payload
216     btstack_linked_list_iterator_t it;
217     btstack_linked_list_iterator_init(&it, &upper_pdu->segments);
218     uint16_t offset = 0;
219     while (btstack_linked_list_iterator_has_next(&it)) {
220         mesh_network_pdu_t *segment = (mesh_network_pdu_t *) btstack_linked_list_iterator_next(&it);
221         btstack_assert(segment->pdu_header.pdu_type == MESH_PDU_TYPE_NETWORK);
222         btstack_assert((offset + segment->len) <= buffer_len);
223         (void) memcpy(&buffer[offset], segment->data, segment->len);
224         offset += segment->len;
225     }
226     return offset;
227 }
228 
229 // store payload in provided list of network pdus
230 static void mesh_segmented_store_payload(const uint8_t * payload, uint16_t payload_len, btstack_linked_list_t * in_segments, btstack_linked_list_t * out_segments){
231     uint16_t payload_offset = 0;
232     uint16_t bytes_current_segment = 0;
233     mesh_network_pdu_t * network_pdu = NULL;
234     while (payload_offset < payload_len){
235         if (bytes_current_segment == 0){
236             network_pdu = (mesh_network_pdu_t *) btstack_linked_list_pop(in_segments);
237             btstack_assert(network_pdu != NULL);
238             btstack_linked_list_add_tail(out_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 // tries allocate and add enough segments to store payload of given size
250 static bool mesh_segmented_allocate_segments(btstack_linked_list_t * segments, uint16_t payload_len){
251     uint16_t storage_size = btstack_linked_list_count(segments) * MESH_NETWORK_PAYLOAD_MAX;
252     while (storage_size < payload_len){
253         mesh_network_pdu_t * network_pdu = mesh_network_pdu_get();
254         if (network_pdu == NULL) break;
255         storage_size += MESH_NETWORK_PAYLOAD_MAX;
256         btstack_linked_list_add(segments, (btstack_linked_item_t *) network_pdu);
257     }
258     return (storage_size >= payload_len);
259 }
260 
261 // stub lower transport
262 
263 static void mesh_upper_transport_dump_pdus(const char *name, btstack_linked_list_t *list){
264     printf("List: %s:\n", name);
265     btstack_linked_list_iterator_t it;
266     btstack_linked_list_iterator_init(&it, list);
267     while (btstack_linked_list_iterator_has_next(&it)){
268         mesh_pdu_t * pdu = (mesh_pdu_t*) btstack_linked_list_iterator_next(&it);
269         printf("- %p\n", pdu);
270         // printf_hexdump( mesh_pdu_data(pdu), mesh_pdu_len(pdu));
271     }
272 }
273 
274 static void mesh_upper_transport_reset_pdus(btstack_linked_list_t *list){
275     while (!btstack_linked_list_empty(list)){
276         mesh_upper_transport_pdu_free((mesh_pdu_t *) btstack_linked_list_pop(list));
277     }
278 }
279 
280 void mesh_upper_transport_dump(void){
281     mesh_upper_transport_dump_pdus("upper_transport_incoming", &upper_transport_incoming);
282 }
283 
284 void mesh_upper_transport_reset(void){
285     crypto_active = 0;
286     mesh_upper_transport_reset_pdus(&upper_transport_incoming);
287 }
288 
289 static mesh_transport_key_t * mesh_upper_transport_get_outgoing_appkey(uint16_t netkey_index, uint16_t appkey_index){
290     // Device Key is fixed
291     if (appkey_index == MESH_DEVICE_KEY_INDEX) {
292         return mesh_transport_key_get(appkey_index);
293     }
294 
295     // Get key refresh state from subnet
296     mesh_subnet_t * subnet = mesh_subnet_get_by_netkey_index(netkey_index);
297     if (subnet == NULL) return NULL;
298 
299     // identify old and new app keys for given appkey_index
300     mesh_transport_key_t * old_key = NULL;
301     mesh_transport_key_t * new_key = NULL;
302     mesh_transport_key_iterator_t it;
303     mesh_transport_key_iterator_init(&it, netkey_index);
304     while (mesh_transport_key_iterator_has_more(&it)){
305         mesh_transport_key_t * transport_key = mesh_transport_key_iterator_get_next(&it);
306         if (transport_key->appkey_index != appkey_index) continue;
307         if (transport_key->old_key == 0) {
308             new_key = transport_key;
309         } else {
310             old_key = transport_key;
311         }
312     }
313 
314     // if no key is marked as old, just use the current one
315     if (old_key == NULL) return new_key;
316 
317     // use new key if it exists in phase two
318     if ((subnet->key_refresh == MESH_KEY_REFRESH_SECOND_PHASE) && (new_key != NULL)){
319         return new_key;
320     } else {
321         return old_key;
322     }
323 }
324 
325 static uint32_t iv_index_for_ivi_nid(uint8_t ivi_nid){
326     // get IV Index and IVI
327     uint32_t iv_index = mesh_get_iv_index();
328     int ivi = ivi_nid >> 7;
329 
330     // if least significant bit differs, use previous IV Index
331     if ((iv_index & 1 ) ^ ivi){
332         iv_index--;
333     }
334     return iv_index;
335 }
336 
337 static void transport_segmented_setup_nonce(uint8_t * nonce, const mesh_pdu_t * pdu){
338     mesh_access_pdu_t * access_pdu;
339     mesh_upper_transport_pdu_t * upper_pdu;
340     switch (pdu->pdu_type){
341         case MESH_PDU_TYPE_ACCESS:
342             access_pdu = (mesh_access_pdu_t *) pdu;
343             nonce[1] = ((access_pdu->flags & MESH_TRANSPORT_FLAG_TRANSMIC_64) != 0) ? 0x80 : 0x00;
344             big_endian_store_24(nonce, 2, access_pdu->seq);
345             big_endian_store_16(nonce, 5, access_pdu->src);
346             big_endian_store_16(nonce, 7, access_pdu->dst);
347             big_endian_store_32(nonce, 9, iv_index_for_ivi_nid(access_pdu->ivi_nid));
348             break;
349         case MESH_PDU_TYPE_UPPER_SEGMENTED_ACCESS:
350         case MESH_PDU_TYPE_UPPER_UNSEGMENTED_ACCESS:
351             upper_pdu = (mesh_upper_transport_pdu_t *) pdu;
352             nonce[1] = ((upper_pdu->flags & MESH_TRANSPORT_FLAG_TRANSMIC_64) != 0) ? 0x80 : 0x00;
353             // 'network header'
354             big_endian_store_24(nonce, 2, upper_pdu->seq);
355             big_endian_store_16(nonce, 5, upper_pdu->src);
356             big_endian_store_16(nonce, 7, upper_pdu->dst);
357             big_endian_store_32(nonce, 9, iv_index_for_ivi_nid(upper_pdu->ivi_nid));
358             break;
359         default:
360             btstack_assert(0);
361             break;
362     }
363 }
364 
365 static void transport_segmented_setup_application_nonce(uint8_t * nonce, const mesh_pdu_t * pdu){
366     nonce[0] = 0x01;
367     transport_segmented_setup_nonce(nonce, pdu);
368     mesh_print_hex("AppNonce", nonce, 13);
369 }
370 
371 static void transport_segmented_setup_device_nonce(uint8_t * nonce, const mesh_pdu_t * pdu){
372     nonce[0] = 0x02;
373     transport_segmented_setup_nonce(nonce, pdu);
374     mesh_print_hex("DeviceNonce", nonce, 13);
375 }
376 
377 static void mesh_upper_transport_process_access_message_done(mesh_access_pdu_t *access_pdu){
378     crypto_active = 0;
379     btstack_assert((access_pdu->ctl_ttl & 0x80) == 0);
380     mesh_lower_transport_message_processed_by_higher_layer(incoming_access_encrypted);
381     incoming_access_encrypted = NULL;
382     incoming_access_decrypted = NULL;
383     mesh_upper_transport_run();
384 }
385 
386 static void mesh_upper_transport_process_control_message_done(mesh_control_pdu_t * control_pdu){
387     UNUSED(control_pdu);
388     crypto_active = 0;
389     incoming_control_pdu = NULL;
390     mesh_upper_transport_run();
391 }
392 
393 static void mesh_upper_transport_network_pdu_freed(void){
394     // call both while prioritizing run outgoing
395     // both functions will trigger request for network pdu if needed
396     if (upper_transport_need_pdu_for_run_outgoing){
397         upper_transport_need_pdu_for_run_outgoing = false;
398         mesh_upper_transport_run();
399     }
400     if (upper_transport_need_pdu_for_send_requests){
401         upper_transport_need_pdu_for_send_requests = false;
402         mesh_upper_transport_schedule_send_requests();
403     }
404 }
405 
406 static void mesh_upper_transport_need_pdu_for_send_requests(void) {
407     bool waiting = upper_transport_need_pdu_for_send_requests || upper_transport_need_pdu_for_run_outgoing;
408     upper_transport_need_pdu_for_send_requests = true;
409     if (waiting == false) {
410         mesh_network_notify_on_freed_pdu(&mesh_upper_transport_network_pdu_freed);
411     }
412 }
413 static void mesh_upper_transport_need_pdu_for_run_outgoing(void) {
414     bool waiting = upper_transport_need_pdu_for_send_requests || upper_transport_need_pdu_for_run_outgoing;
415     upper_transport_need_pdu_for_run_outgoing = true;
416     if (waiting == false) {
417         mesh_network_notify_on_freed_pdu(&mesh_upper_transport_network_pdu_freed);
418     }
419 }
420 
421 static void mesh_upper_transport_deliver_access_message(void) {
422     incoming_access_pdu_ready = false;
423     mesh_access_message_handler(MESH_TRANSPORT_PDU_RECEIVED, MESH_TRANSPORT_STATUS_SUCCESS, (mesh_pdu_t *) incoming_access_decrypted);
424 }
425 
426 static bool mesh_upper_transport_send_requests_pending(void){
427     if (incoming_access_pdu_ready) {
428         return true;
429     }
430     return btstack_linked_list_empty(&upper_transport_send_requests) == false;
431 }
432 
433 static void mesh_upper_transport_schedule_send_requests(void){
434 
435     while (mesh_upper_transport_send_requests_pending()){
436 
437         // get ready
438         bool message_builder_ready = mesh_upper_transport_message_reserve();
439 
440         if (message_builder_ready == false){
441             // waiting for free upper pdu, we will get called again on pdu free
442             if (message_builder_reserved_upper_pdu == false){
443                 return;
444             }
445             // request callback on network pdu free
446             mesh_upper_transport_need_pdu_for_send_requests();
447             return;
448         }
449 
450         // process send requests
451 
452         // incoming access pdu
453         if (incoming_access_pdu_ready){
454             // message builder ready = one outgoing pdu is guaranteed, deliver access pdu
455             mesh_upper_transport_deliver_access_message();
456             continue;
457         }
458 
459         // regular send request
460         btstack_context_callback_registration_t * send_request = (btstack_context_callback_registration_t *) btstack_linked_list_pop(&upper_transport_send_requests);
461         btstack_assert(send_request != NULL);
462         (*send_request->callback)(send_request->context);
463     }
464 }
465 
466 void mesh_upper_transport_request_to_send(btstack_context_callback_registration_t * request){
467     btstack_linked_list_add_tail(&upper_transport_send_requests, (btstack_linked_item_t *) request);
468     mesh_upper_transport_schedule_send_requests();
469 }
470 
471 static void mesh_upper_transport_validate_access_message_ccm(void * arg){
472     UNUSED(arg);
473 
474     uint8_t transmic_len = ((incoming_access_decrypted->flags & MESH_TRANSPORT_FLAG_TRANSMIC_64) != 0) ? 8 : 4;
475     uint8_t * upper_transport_pdu     = incoming_access_decrypted->data;
476     uint8_t   upper_transport_pdu_len = incoming_access_decrypted->len - transmic_len;
477 
478     mesh_print_hex("Decrypted PDU", upper_transport_pdu, upper_transport_pdu_len);
479 
480     // store TransMIC
481     uint8_t trans_mic[8];
482     btstack_crypto_ccm_get_authentication_value(&ccm, trans_mic);
483     mesh_print_hex("TransMIC", trans_mic, transmic_len);
484 
485     if (memcmp(trans_mic, &upper_transport_pdu[upper_transport_pdu_len], transmic_len) == 0){
486         printf("TransMIC matches\n");
487 
488         // remove TransMIC from payload
489         incoming_access_decrypted->len -= transmic_len;
490 
491         // if virtual address, update dst to pseudo_dst
492         if (mesh_network_address_virtual(incoming_access_decrypted->dst)){
493             incoming_access_decrypted->dst = mesh_transport_key_it.address->pseudo_dst;
494         }
495 
496         // pass to upper layer
497         incoming_access_pdu_ready = true;
498         mesh_upper_transport_schedule_send_requests();
499 
500     } else {
501         uint8_t akf = incoming_access_decrypted->akf_aid_control & 0x40;
502         if (akf){
503             printf("TransMIC does not match, try next key\n");
504             mesh_upper_transport_validate_access_message();
505         } else {
506             printf("TransMIC does not match device key, done\n");
507             // done
508             mesh_upper_transport_process_access_message_done(incoming_access_decrypted);
509         }
510     }
511 }
512 
513 static void mesh_upper_transport_validate_access_message_digest(void * arg){
514     UNUSED(arg);
515     uint8_t   transmic_len = ((incoming_access_decrypted->flags & MESH_TRANSPORT_FLAG_TRANSMIC_64) != 0) ? 8 : 4;
516     uint8_t   upper_transport_pdu_len      = incoming_access_decrypted->len - transmic_len;
517     uint8_t * upper_transport_pdu_data_out = incoming_access_decrypted->data;
518 
519     mesh_network_pdu_t * unsegmented_pdu = NULL;
520     mesh_segmented_pdu_t * segmented_pdu = NULL;
521     switch (incoming_access_encrypted->pdu_type){
522         case MESH_PDU_TYPE_SEGMENTED:
523             segmented_pdu = (mesh_segmented_pdu_t *) incoming_access_encrypted;
524             mesh_segmented_pdu_flatten(&segmented_pdu->segments, 12, upper_transport_pdu_data_out);
525             mesh_print_hex("Encrypted Payload:", upper_transport_pdu_data_out, upper_transport_pdu_len);
526             btstack_crypto_ccm_decrypt_block(&ccm, upper_transport_pdu_len, upper_transport_pdu_data_out, upper_transport_pdu_data_out,
527                                              &mesh_upper_transport_validate_access_message_ccm, NULL);
528             break;
529         case MESH_PDU_TYPE_UNSEGMENTED:
530             unsegmented_pdu = (mesh_network_pdu_t *) incoming_access_encrypted;
531             (void)memcpy(upper_transport_pdu_data_out, &unsegmented_pdu->data[10], incoming_access_decrypted->len);
532             btstack_crypto_ccm_decrypt_block(&ccm, upper_transport_pdu_len, upper_transport_pdu_data_out, upper_transport_pdu_data_out,
533                                              &mesh_upper_transport_validate_access_message_ccm, NULL);
534             break;
535         default:
536             btstack_assert(false);
537             break;
538     }
539 
540 }
541 
542 static void mesh_upper_transport_validate_access_message(void){
543     uint8_t   transmic_len = ((incoming_access_decrypted->flags & MESH_TRANSPORT_FLAG_TRANSMIC_64) != 0) ? 8 : 4;
544     uint8_t * upper_transport_pdu_data =  incoming_access_decrypted->data;
545     uint8_t   upper_transport_pdu_len  = incoming_access_decrypted->len - transmic_len;
546 
547     if (!mesh_transport_key_and_virtual_address_iterator_has_more(&mesh_transport_key_it)){
548         printf("No valid transport key found\n");
549         mesh_upper_transport_process_access_message_done(incoming_access_decrypted);
550         return;
551     }
552     mesh_transport_key_and_virtual_address_iterator_next(&mesh_transport_key_it);
553     const mesh_transport_key_t * message_key = mesh_transport_key_it.key;
554 
555     if (message_key->akf){
556         transport_segmented_setup_application_nonce(application_nonce, (mesh_pdu_t *) incoming_access_decrypted);
557     } else {
558         transport_segmented_setup_device_nonce(application_nonce, (mesh_pdu_t *) incoming_access_decrypted);
559     }
560 
561     // store application / device key index
562     mesh_print_hex("AppOrDevKey", message_key->key, 16);
563     incoming_access_decrypted->appkey_index = message_key->appkey_index;
564 
565     mesh_print_hex("EncAccessPayload", upper_transport_pdu_data, upper_transport_pdu_len);
566 
567     // decrypt ccm
568     crypto_active = 1;
569     uint16_t aad_len  = 0;
570     if (mesh_network_address_virtual(incoming_access_decrypted->dst)){
571         aad_len  = 16;
572     }
573     btstack_crypto_ccm_init(&ccm, message_key->key, application_nonce, upper_transport_pdu_len, aad_len, transmic_len);
574 
575     if (aad_len){
576         btstack_crypto_ccm_digest(&ccm, (uint8_t *) mesh_transport_key_it.address->label_uuid, aad_len,
577                                   &mesh_upper_transport_validate_access_message_digest, NULL);
578     } else {
579         mesh_upper_transport_validate_access_message_digest(NULL);
580     }
581 }
582 
583 static void mesh_upper_transport_process_access_message(void){
584     uint8_t   transmic_len = ((incoming_access_decrypted->flags & MESH_TRANSPORT_FLAG_TRANSMIC_64) != 0) ? 8 : 4;
585     uint8_t * upper_transport_pdu     =  incoming_access_decrypted->data;
586     uint8_t   upper_transport_pdu_len = incoming_access_decrypted->len - transmic_len;
587     mesh_print_hex("Upper Transport pdu", upper_transport_pdu, upper_transport_pdu_len);
588 
589     uint8_t aid = incoming_access_decrypted->akf_aid_control & 0x3f;
590     uint8_t akf = (incoming_access_decrypted->akf_aid_control & 0x40) >> 6;
591 
592     printf("AKF: %u\n",   akf);
593     printf("AID: %02x\n", aid);
594 
595     mesh_transport_key_and_virtual_address_iterator_init(&mesh_transport_key_it, incoming_access_decrypted->dst,
596                                                          incoming_access_decrypted->netkey_index, akf, aid);
597     mesh_upper_transport_validate_access_message();
598 }
599 
600 static void mesh_upper_transport_message_received(mesh_pdu_t * pdu){
601     btstack_linked_list_add_tail(&upper_transport_incoming, (btstack_linked_item_t*) pdu);
602     mesh_upper_transport_run();
603 }
604 
605 static void mesh_upper_transport_send_access_segmented(mesh_upper_transport_pdu_t * upper_pdu){
606 
607     mesh_segmented_pdu_t * segmented_pdu   = (mesh_segmented_pdu_t *) upper_pdu->lower_pdu;
608     segmented_pdu->pdu_header.pdu_type = MESH_PDU_TYPE_SEGMENTED;
609 
610     // convert mesh_access_pdu_t into mesh_segmented_pdu_t
611     btstack_linked_list_t free_segments = segmented_pdu->segments;
612     segmented_pdu->segments = NULL;
613     mesh_segmented_store_payload(incoming_pdu_singleton.access.data, upper_pdu->len, &free_segments, &segmented_pdu->segments);
614 
615     // copy meta
616     segmented_pdu->len = upper_pdu->len;
617     segmented_pdu->netkey_index = upper_pdu->netkey_index;
618     segmented_pdu->akf_aid_control = upper_pdu->akf_aid_control;
619     segmented_pdu->flags = upper_pdu->flags;
620 
621     // setup segmented_pdu header
622     // (void)memcpy(segmented_pdu->network_header, upper_pdu->network_header, 9);
623     // TODO: use fields in mesh_segmented_pdu_t and setup network header in lower transport
624     segmented_pdu->ivi_nid = upper_pdu->ivi_nid;
625     segmented_pdu->ctl_ttl = upper_pdu->ctl_ttl;
626     segmented_pdu->seq = upper_pdu->seq;
627     segmented_pdu->src = upper_pdu->src;
628     segmented_pdu->dst = upper_pdu->dst;
629 
630     // queue up
631     upper_pdu->lower_pdu = (mesh_pdu_t *) segmented_pdu;
632     btstack_linked_list_add(&upper_transport_outgoing_active, (btstack_linked_item_t *) upper_pdu);
633 
634     mesh_lower_transport_send_pdu((mesh_pdu_t*) segmented_pdu);
635 }
636 
637 static void mesh_upper_transport_send_access_unsegmented(mesh_upper_transport_pdu_t * upper_pdu){
638 
639     // provide segment
640     mesh_network_pdu_t * network_pdu = (mesh_network_pdu_t *) upper_pdu->lower_pdu;
641 
642     // setup network pdu
643     network_pdu->pdu_header.pdu_type = MESH_PDU_TYPE_UPPER_UNSEGMENTED_ACCESS;
644     network_pdu->data[0] = upper_pdu->ivi_nid;
645     network_pdu->data[1] = upper_pdu->ctl_ttl;
646     big_endian_store_24(network_pdu->data, 2, upper_pdu->seq);
647     big_endian_store_16(network_pdu->data, 5, upper_pdu->src);
648     big_endian_store_16(network_pdu->data, 7, upper_pdu->dst);
649     network_pdu->netkey_index = upper_pdu->netkey_index;
650 
651     // setup access message
652     network_pdu->data[9] = upper_pdu->akf_aid_control;
653     btstack_assert(upper_pdu->len < 15);
654     (void)memcpy(&network_pdu->data[10], &incoming_pdu_singleton.access.data, upper_pdu->len);
655     network_pdu->len = 10 + upper_pdu->len;
656     network_pdu->flags = 0;
657 
658     // queue up
659     btstack_linked_list_add(&upper_transport_outgoing_active, (btstack_linked_item_t *) upper_pdu);
660 
661     mesh_lower_transport_send_pdu((mesh_pdu_t*) network_pdu);
662 }
663 
664 static void mesh_upper_transport_send_access_ccm(void * arg){
665     crypto_active = 0;
666 
667     mesh_upper_transport_pdu_t * upper_pdu = (mesh_upper_transport_pdu_t *) arg;
668     mesh_print_hex("EncAccessPayload", incoming_pdu_singleton.access.data, upper_pdu->len);
669     // store TransMIC
670     btstack_crypto_ccm_get_authentication_value(&ccm, &incoming_pdu_singleton.access.data[upper_pdu->len]);
671     uint8_t transmic_len = ((upper_pdu->flags & MESH_TRANSPORT_FLAG_TRANSMIC_64) != 0) ? 8 : 4;
672     mesh_print_hex("TransMIC", &incoming_pdu_singleton.access.data[upper_pdu->len], transmic_len);
673     upper_pdu->len += transmic_len;
674     mesh_print_hex("UpperTransportPDU", incoming_pdu_singleton.access.data, upper_pdu->len);
675     switch (upper_pdu->pdu_header.pdu_type){
676         case MESH_PDU_TYPE_UPPER_UNSEGMENTED_ACCESS:
677             mesh_upper_transport_send_access_unsegmented(upper_pdu);
678             break;
679         case MESH_PDU_TYPE_UPPER_SEGMENTED_ACCESS:
680             mesh_upper_transport_send_access_segmented(upper_pdu);
681             break;
682         default:
683             btstack_assert(false);
684     }
685 }
686 
687 static void mesh_upper_transport_send_access_digest(void *arg){
688     mesh_upper_transport_pdu_t * upper_pdu = (mesh_upper_transport_pdu_t *) arg;
689     uint16_t  access_pdu_len  = upper_pdu->len;
690     btstack_crypto_ccm_encrypt_block(&ccm, access_pdu_len, incoming_pdu_singleton.access.data, incoming_pdu_singleton.access.data,
691                                      &mesh_upper_transport_send_access_ccm, upper_pdu);
692 }
693 
694 static void mesh_upper_transport_send_access(mesh_upper_transport_pdu_t * upper_pdu){
695 
696     // if dst is virtual address, lookup label uuid and hash
697     uint16_t aad_len = 0;
698     mesh_virtual_address_t * virtual_address = NULL;
699     if (mesh_network_address_virtual(upper_pdu->dst)){
700         virtual_address = mesh_virtual_address_for_pseudo_dst(upper_pdu->dst);
701         if (!virtual_address){
702             printf("No virtual address register for pseudo dst %4x\n", upper_pdu->dst);
703             mesh_access_message_handler(MESH_TRANSPORT_PDU_SENT, MESH_TRANSPORT_STATUS_SEND_FAILED, (mesh_pdu_t *) upper_pdu);
704             return;
705         }
706         // printf("Using hash %4x with LabelUUID: ", virtual_address->hash);
707         // printf_hexdump(virtual_address->label_uuid, 16);
708         aad_len = 16;
709         upper_pdu->dst = virtual_address->hash;
710     }
711 
712     // get app or device key
713     uint16_t appkey_index = upper_pdu->appkey_index;
714     const mesh_transport_key_t * appkey = mesh_upper_transport_get_outgoing_appkey(upper_pdu->netkey_index, appkey_index);
715     if (appkey == NULL){
716         printf("AppKey %04x not found, drop message\n", appkey_index);
717         mesh_access_message_handler(MESH_TRANSPORT_PDU_SENT, MESH_TRANSPORT_STATUS_SEND_FAILED, (mesh_pdu_t *) upper_pdu);
718         return;
719     }
720 
721     // reserve slot
722     mesh_lower_transport_reserve_slot();
723 
724     // reserve one sequence number, which is also used to encrypt access payload
725     uint32_t seq = mesh_sequence_number_next();
726     upper_pdu->flags |= MESH_TRANSPORT_FLAG_SEQ_RESERVED;
727     upper_pdu->seq = seq;
728 
729     // also reserves crypto_buffer
730     crypto_active = 1;
731 
732     // flatten segmented pdu into crypto buffer
733     uint16_t payload_len = mesh_upper_pdu_flatten(upper_pdu, incoming_pdu_singleton.access.data, sizeof(incoming_pdu_singleton.access.data));
734     btstack_assert(payload_len == upper_pdu->len);
735 
736     // Dump PDU
737     printf("[+] Upper transport, send upper (un)segmented Access PDU - dest %04x, seq %06x\n", upper_pdu->dst, upper_pdu->seq);
738     mesh_print_hex("Access Payload", incoming_pdu_singleton.access.data, upper_pdu->len);
739 
740     // setup nonce - uses dst, so after pseudo address translation
741     if (appkey_index == MESH_DEVICE_KEY_INDEX){
742         transport_segmented_setup_device_nonce(application_nonce, (mesh_pdu_t *) upper_pdu);
743     } else {
744         transport_segmented_setup_application_nonce(application_nonce, (mesh_pdu_t *) upper_pdu);
745     }
746 
747     // Dump key
748     mesh_print_hex("AppOrDevKey", appkey->key, 16);
749 
750     // encrypt ccm
751     uint8_t   transmic_len = ((upper_pdu->flags & MESH_TRANSPORT_FLAG_TRANSMIC_64) != 0) ? 8 : 4;
752     uint16_t  access_pdu_len  = upper_pdu->len;
753     btstack_crypto_ccm_init(&ccm, appkey->key, application_nonce, access_pdu_len, aad_len, transmic_len);
754     if (virtual_address){
755         mesh_print_hex("LabelUUID", virtual_address->label_uuid, 16);
756         btstack_crypto_ccm_digest(&ccm, virtual_address->label_uuid, 16,
757                                   &mesh_upper_transport_send_access_digest, upper_pdu);
758     } else {
759         mesh_upper_transport_send_access_digest(upper_pdu);
760     }
761 }
762 
763 static void mesh_upper_transport_send_unsegmented_control_pdu(mesh_network_pdu_t * network_pdu){
764     // reserve slot
765     mesh_lower_transport_reserve_slot();
766     // reserve sequence number
767     uint32_t seq = mesh_sequence_number_next();
768     mesh_network_pdu_set_seq(network_pdu, seq);
769     // Dump PDU
770     uint8_t opcode = network_pdu->data[9];
771     printf("[+] Upper transport, send unsegmented Control PDU %p - seq %06x opcode %02x\n", network_pdu, seq, opcode);
772     mesh_print_hex("Access Payload", &network_pdu->data[10], network_pdu->len - 10);
773 
774     // send
775      mesh_lower_transport_send_pdu((mesh_pdu_t *) network_pdu);
776 }
777 
778 static void mesh_upper_transport_send_segmented_control_pdu(mesh_upper_transport_pdu_t * upper_pdu){
779     // reserve slot
780     mesh_lower_transport_reserve_slot();
781     // reserve sequence number
782     uint32_t seq = mesh_sequence_number_next();
783     upper_pdu->flags |= MESH_TRANSPORT_FLAG_SEQ_RESERVED;
784     upper_pdu->seq = seq;
785     // Dump PDU
786     // uint8_t opcode = upper_pdu->data[0];
787     // printf("[+] Upper transport, send segmented Control PDU %p - seq %06x opcode %02x\n", upper_pdu, seq, opcode);
788     // mesh_print_hex("Access Payload", &upper_pdu->data[1], upper_pdu->len - 1);
789     // send
790     mesh_segmented_pdu_t * segmented_pdu   = (mesh_segmented_pdu_t *) upper_pdu->lower_pdu;
791     segmented_pdu->pdu_header.pdu_type = MESH_PDU_TYPE_SEGMENTED;
792 
793     // lend segments to lower transport pdu
794     segmented_pdu->segments = upper_pdu->segments;
795     upper_pdu->segments = NULL;
796 
797     // copy meta
798     segmented_pdu->len = upper_pdu->len;
799     segmented_pdu->netkey_index = upper_pdu->netkey_index;
800     segmented_pdu->akf_aid_control = upper_pdu->akf_aid_control;
801     segmented_pdu->flags = upper_pdu->flags;
802 
803     btstack_assert((upper_pdu->flags & MESH_TRANSPORT_FLAG_TRANSMIC_64) == 0);
804 
805     // setup segmented_pdu header
806     // TODO: use fields in mesh_segmented_pdu_t and setup network header in lower transport
807     segmented_pdu->ivi_nid = upper_pdu->ivi_nid;
808     segmented_pdu->ctl_ttl = upper_pdu->ctl_ttl;
809     segmented_pdu->seq = upper_pdu->seq;
810     segmented_pdu->src = upper_pdu->src;
811     segmented_pdu->dst = upper_pdu->dst;
812 
813     // queue up
814     upper_pdu->lower_pdu = (mesh_pdu_t *) segmented_pdu;
815     btstack_linked_list_add(&upper_transport_outgoing_active, (btstack_linked_item_t *) upper_pdu);
816 
817     mesh_lower_transport_send_pdu((mesh_pdu_t *) segmented_pdu);
818 }
819 
820 static void mesh_upper_transport_run(void){
821 
822     while(!btstack_linked_list_empty(&upper_transport_incoming)){
823 
824         if (crypto_active) return;
825 
826         // get next message
827         mesh_pdu_t * pdu =  (mesh_pdu_t *) btstack_linked_list_pop(&upper_transport_incoming);
828         mesh_network_pdu_t   * network_pdu;
829         mesh_segmented_pdu_t   * segmented_pdu;
830         switch (pdu->pdu_type){
831             case MESH_PDU_TYPE_UNSEGMENTED:
832                 network_pdu = (mesh_network_pdu_t *) pdu;
833                 // control?
834                 if (mesh_network_control(network_pdu)) {
835 
836                     incoming_control_pdu =  &incoming_pdu_singleton.control;
837                     incoming_control_pdu->pdu_header.pdu_type = MESH_PDU_TYPE_CONTROL;
838                     incoming_control_pdu->len =  network_pdu->len;
839                     incoming_control_pdu->netkey_index =  network_pdu->netkey_index;
840 
841                     uint8_t * lower_transport_pdu = mesh_network_pdu_data(network_pdu);
842 
843                     incoming_control_pdu->akf_aid_control = lower_transport_pdu[0];
844                     incoming_control_pdu->len = network_pdu->len - 10; // 9 header + 1 opcode
845                     (void)memcpy(incoming_control_pdu->data, &lower_transport_pdu[1], incoming_control_pdu->len);
846 
847                     // copy meta data into encrypted pdu buffer
848                     incoming_control_pdu->ivi_nid = network_pdu->data[0];
849                     incoming_control_pdu->ctl_ttl = network_pdu->data[1];
850                     incoming_control_pdu->seq = big_endian_read_24(network_pdu->data, 2);
851                     incoming_control_pdu->src = big_endian_read_16(network_pdu->data, 5);
852                     incoming_control_pdu->dst = big_endian_read_16(network_pdu->data, 7);
853 
854                     mesh_print_hex("Assembled payload", incoming_control_pdu->data, incoming_control_pdu->len);
855 
856                     // free mesh message
857                     mesh_lower_transport_message_processed_by_higher_layer(pdu);
858 
859                     btstack_assert(mesh_control_message_handler != NULL);
860                     mesh_control_message_handler(MESH_TRANSPORT_PDU_RECEIVED, MESH_TRANSPORT_STATUS_SUCCESS, (mesh_pdu_t*) incoming_control_pdu);
861 
862                 } else {
863 
864                     incoming_access_encrypted = (mesh_pdu_t *) network_pdu;
865 
866                     incoming_access_decrypted = &incoming_pdu_singleton.access;
867                     incoming_access_decrypted->pdu_header.pdu_type = MESH_PDU_TYPE_ACCESS;
868                     incoming_access_decrypted->flags = 0;
869                     incoming_access_decrypted->netkey_index = network_pdu->netkey_index;
870                     incoming_access_decrypted->akf_aid_control = network_pdu->data[9];
871                     incoming_access_decrypted->len = network_pdu->len - 10; // 9 header + 1 AID
872                     incoming_access_decrypted->ivi_nid = network_pdu->data[0];
873                     incoming_access_decrypted->ctl_ttl = network_pdu->data[1];
874                     incoming_access_decrypted->seq = big_endian_read_24(network_pdu->data, 2);
875                     incoming_access_decrypted->src = big_endian_read_16(network_pdu->data, 5);
876                     incoming_access_decrypted->dst = big_endian_read_16(network_pdu->data, 7);
877 
878                     mesh_upper_transport_process_access_message();
879                 }
880                 break;
881             case MESH_PDU_TYPE_SEGMENTED:
882                 segmented_pdu = (mesh_segmented_pdu_t *) pdu;
883                 uint8_t ctl = segmented_pdu->ctl_ttl >> 7;
884                 if (ctl){
885                     incoming_control_pdu=  &incoming_pdu_singleton.control;
886                     incoming_control_pdu->pdu_header.pdu_type = MESH_PDU_TYPE_CONTROL;
887 
888                     // flatten
889                     mesh_segmented_pdu_flatten(&segmented_pdu->segments, 8, incoming_control_pdu->data);
890 
891                     // copy meta data into encrypted pdu buffer
892                     incoming_control_pdu->flags = 0;
893                     incoming_control_pdu->len =  segmented_pdu->len;
894                     incoming_control_pdu->netkey_index =  segmented_pdu->netkey_index;
895                     incoming_control_pdu->akf_aid_control = segmented_pdu->akf_aid_control;
896                     incoming_control_pdu->ivi_nid = segmented_pdu->ivi_nid;
897                     incoming_control_pdu->ctl_ttl = segmented_pdu->ctl_ttl;
898                     incoming_control_pdu->seq = segmented_pdu->seq;
899                     incoming_control_pdu->src = segmented_pdu->src;
900                     incoming_control_pdu->dst = segmented_pdu->dst;
901 
902                     mesh_print_hex("Assembled payload", incoming_control_pdu->data, incoming_control_pdu->len);
903 
904                     // free mesh message
905                     mesh_lower_transport_message_processed_by_higher_layer((mesh_pdu_t *)segmented_pdu);
906 
907                     btstack_assert(mesh_control_message_handler != NULL);
908                     mesh_control_message_handler(MESH_TRANSPORT_PDU_RECEIVED, MESH_TRANSPORT_STATUS_SUCCESS, (mesh_pdu_t*) incoming_control_pdu);
909 
910                 } else {
911 
912                     incoming_access_encrypted = (mesh_pdu_t *) segmented_pdu;
913 
914                     incoming_access_decrypted = &incoming_pdu_singleton.access;
915                     incoming_access_decrypted->pdu_header.pdu_type = MESH_PDU_TYPE_ACCESS;
916                     incoming_access_decrypted->flags = segmented_pdu->flags;
917                     incoming_access_decrypted->len =  segmented_pdu->len;
918                     incoming_access_decrypted->netkey_index = segmented_pdu->netkey_index;
919                     incoming_access_decrypted->akf_aid_control =  segmented_pdu->akf_aid_control;
920                     incoming_access_decrypted->ivi_nid = segmented_pdu->ivi_nid;
921                     incoming_access_decrypted->ctl_ttl = segmented_pdu->ctl_ttl;
922                     incoming_access_decrypted->seq = segmented_pdu->seq;
923                     incoming_access_decrypted->src = segmented_pdu->src;
924                     incoming_access_decrypted->dst = segmented_pdu->dst;
925 
926                     mesh_upper_transport_process_access_message();
927                 }
928                 break;
929             default:
930                 btstack_assert(0);
931                 break;
932         }
933     }
934 
935     btstack_linked_list_iterator_t it;
936     btstack_linked_list_iterator_init(&it, &upper_transport_outgoing);
937     while (btstack_linked_list_iterator_has_next(&it)){
938 
939         if (crypto_active) break;
940 
941         mesh_pdu_t * pdu =  (mesh_pdu_t *) btstack_linked_list_iterator_next(&it);
942         if (mesh_lower_transport_can_send_to_dest(mesh_pdu_dst(pdu)) == false) {
943             // skip pdu for now
944             continue;
945         }
946 
947         mesh_upper_transport_pdu_t * upper_pdu;
948         mesh_segmented_pdu_t * segmented_pdu;
949         uint8_t transmic_len;
950         bool ok;
951         bool abort_outgoing_loop = false;
952 
953         switch (pdu->pdu_type){
954             case MESH_PDU_TYPE_UPPER_UNSEGMENTED_CONTROL:
955                 // control pdus can go through directly
956                 btstack_assert(mesh_pdu_ctl(pdu) != 0);
957                 btstack_linked_list_iterator_remove(&it);
958                 mesh_upper_transport_send_unsegmented_control_pdu((mesh_network_pdu_t *) pdu);
959                 break;
960             case MESH_PDU_TYPE_UPPER_SEGMENTED_CONTROL:
961                 // control pdus can go through directly
962                 btstack_assert(mesh_pdu_ctl(pdu) != 0);
963                 btstack_linked_list_iterator_remove(&it);
964                 mesh_upper_transport_send_segmented_control_pdu((mesh_upper_transport_pdu_t *) pdu);
965                 break;
966             case MESH_PDU_TYPE_UPPER_SEGMENTED_ACCESS:
967                 // segmented access pdus required a mesh-segmented-pdu
968                 upper_pdu = (mesh_upper_transport_pdu_t *) pdu;
969                 if (upper_pdu->lower_pdu == NULL){
970                     upper_pdu->lower_pdu  = (mesh_pdu_t *) btstack_memory_mesh_segmented_pdu_get();
971                 }
972                 if (upper_pdu->lower_pdu == NULL){
973                     mesh_upper_transport_need_pdu_for_run_outgoing();
974                     abort_outgoing_loop = true;
975                     break;
976                 }
977                 segmented_pdu = (mesh_segmented_pdu_t *) upper_pdu->lower_pdu;
978                 segmented_pdu->pdu_header.pdu_type = MESH_PDU_TYPE_SEGMENTED;
979                 // and a mesh-network-pdu for each segment in upper pdu
980                 transmic_len = ((upper_pdu->flags & MESH_TRANSPORT_FLAG_TRANSMIC_64) != 0) ? 8 : 4;
981                 ok = mesh_segmented_allocate_segments(&segmented_pdu->segments, upper_pdu->len + transmic_len);
982                 if (!ok) {
983                     abort_outgoing_loop = true;
984                     break;
985                 }
986                 // all buffers available, get started
987                 btstack_linked_list_iterator_remove(&it);
988                 mesh_upper_transport_send_access(upper_pdu);
989                 break;
990             case MESH_PDU_TYPE_UPPER_UNSEGMENTED_ACCESS:
991                 // unsegmented access pdus require a single mesh-network-dpu
992                 upper_pdu = (mesh_upper_transport_pdu_t *) pdu;
993                 if (upper_pdu->lower_pdu == NULL){
994                     upper_pdu->lower_pdu = (mesh_pdu_t *) mesh_network_pdu_get();
995                 }
996                 if (upper_pdu->lower_pdu == NULL) {
997                     mesh_upper_transport_need_pdu_for_run_outgoing();
998                     abort_outgoing_loop = true;
999                     break;
1000                 }
1001                 btstack_linked_list_iterator_remove(&it);
1002                 mesh_upper_transport_send_access((mesh_upper_transport_pdu_t *) pdu);
1003                 break;
1004             default:
1005                 btstack_assert(false);
1006                 break;
1007         }
1008         if (abort_outgoing_loop) {
1009             break;
1010         }
1011     }
1012 }
1013 
1014 static mesh_upper_transport_pdu_t * mesh_upper_transport_find_and_remove_pdu_for_lower(mesh_pdu_t * pdu_to_find){
1015     btstack_linked_list_iterator_t it;
1016     btstack_linked_list_iterator_init(&it, &upper_transport_outgoing_active);
1017     mesh_upper_transport_pdu_t * upper_pdu;
1018     while (btstack_linked_list_iterator_has_next(&it)){
1019         mesh_pdu_t * mesh_pdu = (mesh_pdu_t *) btstack_linked_list_iterator_next(&it);
1020         switch (mesh_pdu->pdu_type){
1021             case MESH_PDU_TYPE_UPPER_SEGMENTED_CONTROL:
1022             case MESH_PDU_TYPE_UPPER_UNSEGMENTED_ACCESS:
1023             case MESH_PDU_TYPE_UPPER_SEGMENTED_ACCESS:
1024                 upper_pdu = (mesh_upper_transport_pdu_t *) mesh_pdu;
1025                 if (upper_pdu->lower_pdu == pdu_to_find){
1026                     btstack_linked_list_iterator_remove(&it);
1027                     return upper_pdu;
1028                 }
1029                 break;
1030             default:
1031                 break;
1032         }
1033     }
1034     return NULL;
1035 }
1036 
1037 static void mesh_upper_transport_pdu_handler(mesh_transport_callback_type_t callback_type, mesh_transport_status_t status, mesh_pdu_t * pdu){
1038     mesh_upper_transport_pdu_t * upper_pdu;
1039     mesh_segmented_pdu_t * segmented_pdu;
1040     switch (callback_type){
1041         case MESH_TRANSPORT_PDU_RECEIVED:
1042             mesh_upper_transport_message_received(pdu);
1043             break;
1044         case MESH_TRANSPORT_PDU_SENT:
1045             switch (pdu->pdu_type){
1046                 case MESH_PDU_TYPE_SEGMENTED:
1047                     // try to find in outgoing active
1048                     upper_pdu = mesh_upper_transport_find_and_remove_pdu_for_lower(pdu);
1049                     btstack_assert(upper_pdu != NULL);
1050                     segmented_pdu = (mesh_segmented_pdu_t *) pdu;
1051                     // free chunks
1052                     while (!btstack_linked_list_empty(&segmented_pdu->segments)){
1053                         mesh_network_pdu_t * chunk_pdu = (mesh_network_pdu_t *) btstack_linked_list_pop(&segmented_pdu->segments);
1054                         mesh_network_pdu_free(chunk_pdu);
1055                     }
1056                     // free segmented pdu
1057                     btstack_memory_mesh_segmented_pdu_free(segmented_pdu);
1058                     upper_pdu->lower_pdu = NULL;
1059                     switch (upper_pdu->pdu_header.pdu_type){
1060                         case MESH_PDU_TYPE_UPPER_SEGMENTED_CONTROL:
1061                             mesh_control_message_handler(callback_type, status, (mesh_pdu_t *) upper_pdu);
1062                             break;
1063                         case MESH_PDU_TYPE_UPPER_SEGMENTED_ACCESS:
1064                             mesh_access_message_handler(callback_type, status, (mesh_pdu_t *) upper_pdu);
1065                             break;
1066                         default:
1067                             btstack_assert(false);
1068                             break;
1069                     }
1070                     break;
1071                 case MESH_PDU_TYPE_UPPER_UNSEGMENTED_ACCESS:
1072                     // find corresponding upper transport pdu and free single segment
1073                     upper_pdu = mesh_upper_transport_find_and_remove_pdu_for_lower(pdu);
1074                     btstack_assert(upper_pdu != NULL);
1075                     btstack_assert(upper_pdu->lower_pdu == (mesh_pdu_t *) pdu);
1076                     mesh_network_pdu_free((mesh_network_pdu_t *) pdu);
1077                     upper_pdu->lower_pdu = NULL;
1078                     mesh_access_message_handler(callback_type, status, (mesh_pdu_t*) upper_pdu);
1079                     break;
1080                 case MESH_PDU_TYPE_UPPER_UNSEGMENTED_CONTROL:
1081                     mesh_access_message_handler(callback_type, status, pdu);
1082                     break;
1083                 default:
1084                     btstack_assert(false);
1085                     break;
1086             }
1087             mesh_upper_transport_run();
1088             break;
1089         default:
1090             break;
1091     }
1092 }
1093 
1094 void mesh_upper_transport_pdu_free(mesh_pdu_t * pdu){
1095     btstack_assert(pdu != NULL);
1096     mesh_network_pdu_t   * network_pdu;
1097     mesh_segmented_pdu_t   * message_pdu;
1098     mesh_upper_transport_pdu_t * upper_pdu;
1099     switch (pdu->pdu_type) {
1100         case MESH_PDU_TYPE_UPPER_UNSEGMENTED_CONTROL:
1101         case MESH_PDU_TYPE_NETWORK:
1102             network_pdu = (mesh_network_pdu_t *) pdu;
1103             mesh_network_pdu_free(network_pdu);
1104             break;
1105         case MESH_PDU_TYPE_SEGMENTED:
1106             message_pdu = (mesh_segmented_pdu_t *) pdu;
1107             mesh_segmented_pdu_free(message_pdu);
1108             break;
1109         case MESH_PDU_TYPE_UPPER_UNSEGMENTED_ACCESS:
1110         case MESH_PDU_TYPE_UPPER_SEGMENTED_ACCESS:
1111         case MESH_PDU_TYPE_UPPER_SEGMENTED_CONTROL:
1112             upper_pdu = (mesh_upper_transport_pdu_t *) pdu;
1113             while (upper_pdu->segments) {
1114                 mesh_network_pdu_t *segment = (mesh_network_pdu_t *) btstack_linked_list_pop(&upper_pdu->segments);
1115                 mesh_network_pdu_free(segment);
1116             }
1117             btstack_memory_mesh_upper_transport_pdu_free(upper_pdu);
1118             // check if send request can be handled now
1119             mesh_upper_transport_schedule_send_requests();
1120             break;
1121         default:
1122             btstack_assert(false);
1123             break;
1124     }
1125 }
1126 
1127 void mesh_upper_transport_message_processed_by_higher_layer(mesh_pdu_t * pdu){
1128     crypto_active = 0;
1129     switch (pdu->pdu_type){
1130         case MESH_PDU_TYPE_ACCESS:
1131             mesh_upper_transport_process_access_message_done((mesh_access_pdu_t *) pdu);
1132         case MESH_PDU_TYPE_CONTROL:
1133             mesh_upper_transport_process_control_message_done((mesh_control_pdu_t *) pdu);
1134             break;
1135         default:
1136             btstack_assert(0);
1137             break;
1138     }
1139 }
1140 
1141 void mesh_upper_transport_send_access_pdu(mesh_pdu_t *pdu){
1142     switch (pdu->pdu_type){
1143         case MESH_PDU_TYPE_UPPER_SEGMENTED_ACCESS:
1144         case MESH_PDU_TYPE_UPPER_UNSEGMENTED_ACCESS:
1145             break;
1146         default:
1147             btstack_assert(false);
1148             break;
1149     }
1150 
1151     btstack_assert(((mesh_upper_transport_pdu_t *) pdu)->lower_pdu == NULL);
1152 
1153     btstack_linked_list_add_tail(&upper_transport_outgoing, (btstack_linked_item_t*) pdu);
1154     mesh_upper_transport_run();
1155 }
1156 
1157 void mesh_upper_transport_send_control_pdu(mesh_pdu_t * pdu){
1158     switch (pdu->pdu_type){
1159         case MESH_PDU_TYPE_UPPER_SEGMENTED_CONTROL:
1160             break;
1161         case MESH_PDU_TYPE_UPPER_UNSEGMENTED_CONTROL:
1162             btstack_assert( ((mesh_network_pdu_t *) pdu)->len >= 9);
1163             break;
1164         default:
1165             btstack_assert(false);
1166             break;
1167     }
1168 
1169     btstack_linked_list_add_tail(&upper_transport_outgoing, (btstack_linked_item_t*) pdu);
1170     mesh_upper_transport_run();
1171 }
1172 
1173 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,
1174                                                                   const uint8_t * control_pdu_data, uint16_t control_pdu_len){
1175 
1176     btstack_assert(network_pdu != NULL);
1177     btstack_assert(control_pdu_len <= 11);
1178 
1179     const mesh_network_key_t * network_key = mesh_network_key_list_get(netkey_index);
1180     if (!network_key) return 1;
1181 
1182     uint8_t transport_pdu_data[12];
1183     transport_pdu_data[0] = opcode;
1184     (void)memcpy(&transport_pdu_data[1], control_pdu_data, control_pdu_len);
1185     uint16_t transport_pdu_len = control_pdu_len + 1;
1186 
1187     // setup network_pdu
1188     network_pdu->pdu_header.pdu_type = MESH_PDU_TYPE_UPPER_UNSEGMENTED_CONTROL;
1189     mesh_network_setup_pdu(network_pdu, netkey_index, network_key->nid, 1, ttl, 0, src, dest, transport_pdu_data, transport_pdu_len);
1190 
1191     return 0;
1192 }
1193 
1194 uint8_t mesh_upper_transport_setup_segmented_control_pdu_header(mesh_upper_transport_pdu_t * upper_pdu, uint16_t netkey_index, uint8_t ttl, uint16_t src, uint16_t dest, uint8_t opcode){
1195 
1196     const mesh_network_key_t * network_key = mesh_network_key_list_get(netkey_index);
1197     if (!network_key) return 1;
1198 
1199     upper_pdu->ivi_nid = network_key->nid | ((mesh_get_iv_index_for_tx() & 1) << 7);
1200     upper_pdu->ctl_ttl = ttl;
1201     upper_pdu->src = src;
1202     upper_pdu->dst = dest;
1203     upper_pdu->netkey_index = netkey_index;
1204     upper_pdu->akf_aid_control = opcode;
1205     return 0;
1206 }
1207 
1208 static uint8_t mesh_upper_transport_setup_upper_access_pdu_header(mesh_upper_transport_pdu_t * upper_pdu, uint16_t netkey_index,
1209                                                                   uint16_t appkey_index, uint8_t ttl, uint16_t src, uint16_t dest, uint8_t szmic){
1210 
1211     // get app or device key
1212     const mesh_transport_key_t *appkey;
1213     appkey = mesh_transport_key_get(appkey_index);
1214     if (appkey == NULL) {
1215         printf("[!] Upper transport, setup segmented Access PDU - appkey_index %x unknown\n", appkey_index);
1216         return 1;
1217     }
1218     uint8_t akf_aid = (appkey->akf << 6) | appkey->aid;
1219 
1220     // lookup network by netkey_index
1221     const mesh_network_key_t *network_key = mesh_network_key_list_get(netkey_index);
1222     if (!network_key) return 1;
1223     if (network_key == NULL) {
1224         printf("[!] Upper transport, setup segmented Access PDU - netkey_index %x unknown\n", appkey_index);
1225         return 1;
1226     }
1227 
1228     // store in transport pdu
1229     upper_pdu->ivi_nid = network_key->nid | ((mesh_get_iv_index_for_tx() & 1) << 7);
1230     upper_pdu->ctl_ttl = ttl;
1231     upper_pdu->src = src;
1232     upper_pdu->dst = dest;
1233     upper_pdu->netkey_index = netkey_index;
1234     upper_pdu->appkey_index = appkey_index;
1235     upper_pdu->akf_aid_control = akf_aid;
1236     if (szmic) {
1237         upper_pdu->flags |= MESH_TRANSPORT_FLAG_TRANSMIC_64;
1238     }
1239     return 0;
1240 }
1241 
1242 uint8_t mesh_upper_transport_setup_access_pdu_header(mesh_pdu_t * pdu, uint16_t netkey_index, uint16_t appkey_index,
1243                                                      uint8_t ttl, uint16_t src, uint16_t dest, uint8_t szmic){
1244     switch (pdu->pdu_type){
1245         case MESH_PDU_TYPE_UPPER_SEGMENTED_ACCESS:
1246         case MESH_PDU_TYPE_UPPER_UNSEGMENTED_ACCESS:
1247             return mesh_upper_transport_setup_upper_access_pdu_header((mesh_upper_transport_pdu_t *) pdu, netkey_index,
1248                                                                appkey_index, ttl, src, dest, szmic);
1249         default:
1250             btstack_assert(false);
1251             return 1;
1252     }
1253 }
1254 
1255 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)) {
1256     mesh_access_message_handler = callback;
1257 }
1258 
1259 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)){
1260     mesh_control_message_handler = callback;
1261 }
1262 
1263 void mesh_upper_transport_init(){
1264     mesh_lower_transport_set_higher_layer_handler(&mesh_upper_transport_pdu_handler);
1265 }
1266 
1267 bool mesh_upper_transport_message_reserve(void){
1268     if (message_builder_reserved_upper_pdu == NULL){
1269         message_builder_reserved_upper_pdu = btstack_memory_mesh_upper_transport_pdu_get();
1270     }
1271     if (message_builder_reserved_upper_pdu == NULL){
1272         return false;
1273     }
1274     while (message_builder_num_network_pdus_reserved < MESSAGE_BUILDER_MAX_NUM_NETWORK_PDUS){
1275         mesh_network_pdu_t * network_pdu = mesh_network_pdu_get();
1276         if (network_pdu == NULL){
1277             return false;
1278         }
1279         btstack_linked_list_add(&message_builder_reserved_network_pdus, (btstack_linked_item_t *) network_pdu);
1280         message_builder_num_network_pdus_reserved++;
1281     }
1282     return true;
1283 }
1284 
1285 void mesh_upper_transport_message_init(mesh_upper_transport_builder_t * builder, mesh_pdu_type_t pdu_type) {
1286     btstack_assert(builder != NULL);
1287 
1288     // use reserved buffer if available
1289     if (message_builder_reserved_upper_pdu != NULL){
1290         builder->pdu = message_builder_reserved_upper_pdu;
1291         message_builder_reserved_upper_pdu = NULL;
1292     } else {
1293         builder->pdu = btstack_memory_mesh_upper_transport_pdu_get();
1294     }
1295     if (!builder->pdu) return;
1296 
1297     builder->segment = NULL;
1298     builder->pdu->pdu_header.pdu_type = pdu_type;
1299     builder->pdu->ack_opcode = MESH_ACCESS_OPCODE_NOT_SET;
1300 }
1301 
1302 
1303 void mesh_upper_transport_message_add_data(mesh_upper_transport_builder_t * builder, const uint8_t * data, uint16_t data_len){
1304     btstack_assert(builder != NULL);
1305 
1306     if (builder->pdu == NULL) return;
1307 
1308     builder->pdu->len += data_len;
1309 
1310     uint16_t bytes_current_segment = 0;
1311     if (builder->segment){
1312         bytes_current_segment = MESH_NETWORK_PAYLOAD_MAX - builder->segment->len;
1313     }
1314     while (data_len > 0){
1315         if (bytes_current_segment == 0){
1316             // use reserved buffer if available
1317             if (message_builder_num_network_pdus_reserved > 0){
1318                 message_builder_num_network_pdus_reserved--;
1319                 builder->segment = (mesh_network_pdu_t *) btstack_linked_list_pop(&message_builder_reserved_network_pdus);
1320             } else {
1321                 builder->segment = (mesh_network_pdu_t *) mesh_network_pdu_get();
1322             }
1323             if (builder->segment == NULL) {
1324                 mesh_upper_transport_pdu_free((mesh_pdu_t *) builder->pdu);
1325                 builder->pdu = NULL;
1326                 return;
1327             }
1328             btstack_linked_list_add_tail(&builder->pdu->segments, (btstack_linked_item_t *) builder->segment);
1329             bytes_current_segment = MESH_NETWORK_PAYLOAD_MAX;
1330         }
1331         uint16_t bytes_to_copy = btstack_min(bytes_current_segment, data_len);
1332         (void) memcpy(&builder->segment->data[builder->segment->len], data, bytes_to_copy);
1333         builder->segment->len += bytes_to_copy;
1334         bytes_current_segment -= bytes_to_copy;
1335         data                  += bytes_to_copy;
1336         data_len              -= bytes_to_copy;
1337     }
1338 }
1339 
1340 void mesh_upper_transport_message_add_uint8(mesh_upper_transport_builder_t * builder, uint8_t value){
1341     mesh_upper_transport_message_add_data(builder, &value, 1);
1342 }
1343 
1344 void mesh_upper_transport_message_add_uint16(mesh_upper_transport_builder_t * builder, uint16_t value){
1345     uint8_t buffer[2];
1346     little_endian_store_16(buffer, 0, value);
1347     mesh_upper_transport_message_add_data(builder, buffer, sizeof(buffer));
1348 }
1349 
1350 void mesh_upper_transport_message_add_uint24(mesh_upper_transport_builder_t * builder, uint32_t value){
1351     uint8_t buffer[3];
1352     little_endian_store_24(buffer, 0, value);
1353     mesh_upper_transport_message_add_data(builder, buffer, sizeof(buffer));
1354 }
1355 
1356 void mesh_upper_transport_message_add_uint32(mesh_upper_transport_builder_t * builder, uint32_t value){
1357     uint8_t buffer[4];
1358     little_endian_store_32(buffer, 0, value);
1359     mesh_upper_transport_message_add_data(builder, buffer, sizeof(buffer));
1360 }
1361 
1362 mesh_upper_transport_pdu_t * mesh_upper_transport_message_finalize(mesh_upper_transport_builder_t * builder){
1363     return builder->pdu;
1364 }
1365