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1 /******************************************************************************
2  *
3  *  Copyright 2008-2012 Broadcom Corporation
4  *
5  *  Licensed under the Apache License, Version 2.0 (the "License");
6  *  you may not use this file except in compliance with the License.
7  *  You may obtain a copy of the License at:
8  *
9  *  http://www.apache.org/licenses/LICENSE-2.0
10  *
11  *  Unless required by applicable law or agreed to in writing, software
12  *  distributed under the License is distributed on an "AS IS" BASIS,
13  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  *  See the License for the specific language governing permissions and
15  *  limitations under the License.
16  *
17  ******************************************************************************/
18 
19 /******************************************************************************
20  *
21  *  this file contains the main GATT server attributes access request
22  *  handling functions.
23  *
24  ******************************************************************************/
25 
26 #include <bluetooth/log.h>
27 
28 #include <deque>
29 #include <map>
30 
31 #include "base/functional/callback.h"
32 #include "btif/include/btif_storage.h"
33 #include "eatt/eatt.h"
34 #include "gatt_api.h"
35 #include "gatt_int.h"
36 #include "device/include/interop.h"
37 #include "internal_include/bt_target.h"
38 #include "stack/include/bt_types.h"
39 #include "stack/include/bt_uuid16.h"
40 #include "stack/include/btm_sec_api.h"
41 #include "stack/include/btm_ble_addr.h"
42 #include "types/bluetooth/uuid.h"
43 #include "types/raw_address.h"
44 
45 using bluetooth::Uuid;
46 using namespace bluetooth;
47 
48 #define BLE_GATT_SVR_SUP_FEAT_EATT_BITMASK 0x01
49 
50 #define BLE_GATT_CL_SUP_FEAT_CACHING_BITMASK 0x01
51 #define BLE_GATT_CL_SUP_FEAT_EATT_BITMASK 0x02
52 #define BLE_GATT_CL_SUP_FEAT_MULTI_NOTIF_BITMASK 0x04
53 
54 #define BLE_GATT_CL_ANDROID_SUP_FEAT \
55   (BLE_GATT_CL_SUP_FEAT_EATT_BITMASK | BLE_GATT_CL_SUP_FEAT_MULTI_NOTIF_BITMASK)
56 
57 using gatt_sr_supported_feat_cb = base::OnceCallback<void(const RawAddress&, uint8_t)>;
58 using gatt_sirk_cb = base::OnceCallback<void(tGATT_STATUS status, const RawAddress&,
59                                              uint8_t sirk_type, Octet16& sirk)>;
60 
61 typedef struct {
62   uint16_t op_uuid;
63   gatt_sr_supported_feat_cb cb;
64   gatt_sirk_cb sirk_cb;
65 } gatt_op_cb_data;
66 
67 static std::map<tCONN_ID, std::deque<gatt_op_cb_data>> OngoingOps;
68 
69 static void gatt_request_cback(tCONN_ID conn_id, uint32_t trans_id, uint8_t op_code,
70                                tGATTS_DATA* p_data);
71 static void gatt_connect_cback(tGATT_IF /* gatt_if */, const RawAddress& bda, tCONN_ID conn_id,
72                                bool connected, tGATT_DISCONN_REASON reason,
73                                tBT_TRANSPORT transport);
74 static void gatt_disc_res_cback(tCONN_ID conn_id, tGATT_DISC_TYPE disc_type,
75                                 tGATT_DISC_RES* p_data);
76 static void gatt_disc_cmpl_cback(tCONN_ID conn_id, tGATT_DISC_TYPE disc_type, tGATT_STATUS status);
77 static void gatt_cl_op_cmpl_cback(tCONN_ID conn_id, tGATTC_OPTYPE op, tGATT_STATUS status,
78                                   tGATT_CL_COMPLETE* p_data);
79 
80 static void gatt_cl_start_config_ccc(tGATT_PROFILE_CLCB* p_clcb);
81 
82 static bool gatt_sr_is_robust_caching_enabled();
83 
84 static bool read_sr_supported_feat_req(tCONN_ID conn_id,
85                                        base::OnceCallback<void(const RawAddress&, uint8_t)> cb);
86 static bool read_sr_sirk_req(tCONN_ID conn_id,
87                              base::OnceCallback<void(tGATT_STATUS status, const RawAddress&,
88                                                      uint8_t sirk_type, Octet16& sirk)>
89                                      cb);
90 
91 static tGATT_STATUS gatt_sr_read_db_hash(tCONN_ID conn_id, tGATT_VALUE* p_value);
92 static tGATT_STATUS gatt_sr_read_cl_supp_feat(tCONN_ID conn_id, tGATT_VALUE* p_value);
93 static tGATT_STATUS gatt_sr_write_cl_supp_feat(tCONN_ID conn_id, tGATT_WRITE_REQ* p_data);
94 
95 static tGATT_CBACK gatt_profile_cback = {
96         .p_conn_cb = gatt_connect_cback,
97         .p_cmpl_cb = gatt_cl_op_cmpl_cback,
98         .p_disc_res_cb = gatt_disc_res_cback,
99         .p_disc_cmpl_cb = gatt_disc_cmpl_cback,
100         .p_req_cb = gatt_request_cback,
101         .p_enc_cmpl_cb = nullptr,
102         .p_congestion_cb = nullptr,
103         .p_phy_update_cb = nullptr,
104         .p_conn_update_cb = nullptr,
105         .p_subrate_chg_cb = nullptr,
106 };
107 
108 /*******************************************************************************
109  *
110  * Function         gatt_profile_find_conn_id_by_bd_addr
111  *
112  * Description      Find the connection ID by remote address
113  *
114  * Returns          Connection ID
115  *
116  ******************************************************************************/
gatt_profile_find_conn_id_by_bd_addr(const RawAddress & remote_bda)117 tCONN_ID gatt_profile_find_conn_id_by_bd_addr(const RawAddress& remote_bda) {
118   tCONN_ID conn_id = GATT_INVALID_CONN_ID;
119   if (!GATT_GetConnIdIfConnected(gatt_cb.gatt_if, remote_bda, &conn_id, BT_TRANSPORT_LE)) {
120     log::warn(
121             "Unable to get GATT connection id if connected peer:{} gatt_if:{} "
122             "transport:{}",
123             remote_bda, gatt_cb.gatt_if, bt_transport_text(BT_TRANSPORT_LE));
124   }
125   if (conn_id == GATT_INVALID_CONN_ID) {
126     if (!GATT_GetConnIdIfConnected(gatt_cb.gatt_if, remote_bda, &conn_id, BT_TRANSPORT_BR_EDR)) {
127       log::warn(
128               "Unable to get GATT connection id if connected peer:{} gatt_if:{} "
129               "transport:{}",
130               remote_bda, gatt_cb.gatt_if, bt_transport_text(BT_TRANSPORT_BR_EDR));
131     }
132   }
133   return conn_id;
134 }
135 
136 /*******************************************************************************
137  *
138  * Function         gatt_profile_find_clcb_by_conn_id
139  *
140  * Description      find clcb by Connection ID
141  *
142  * Returns          Pointer to the found link conenction control block.
143  *
144  ******************************************************************************/
gatt_profile_find_clcb_by_conn_id(tCONN_ID conn_id)145 static tGATT_PROFILE_CLCB* gatt_profile_find_clcb_by_conn_id(tCONN_ID conn_id) {
146   uint8_t i_clcb;
147   tGATT_PROFILE_CLCB* p_clcb = NULL;
148 
149   for (i_clcb = 0, p_clcb = gatt_cb.profile_clcb; i_clcb < GATT_MAX_APPS; i_clcb++, p_clcb++) {
150     if (p_clcb->in_use && p_clcb->conn_id == conn_id) {
151       return p_clcb;
152     }
153   }
154 
155   return NULL;
156 }
157 
158 /*******************************************************************************
159  *
160  * Function         gatt_profile_find_clcb_by_bd_addr
161  *
162  * Description      The function searches all LCBs with macthing bd address.
163  *
164  * Returns          Pointer to the found link conenction control block.
165  *
166  ******************************************************************************/
gatt_profile_find_clcb_by_bd_addr(const RawAddress & bda,tBT_TRANSPORT transport)167 static tGATT_PROFILE_CLCB* gatt_profile_find_clcb_by_bd_addr(const RawAddress& bda,
168                                                              tBT_TRANSPORT transport) {
169   uint8_t i_clcb;
170   tGATT_PROFILE_CLCB* p_clcb = NULL;
171 
172   for (i_clcb = 0, p_clcb = gatt_cb.profile_clcb; i_clcb < GATT_MAX_APPS; i_clcb++, p_clcb++) {
173     if (p_clcb->in_use && p_clcb->transport == transport && p_clcb->connected &&
174         p_clcb->bda == bda) {
175       return p_clcb;
176     }
177   }
178 
179   return NULL;
180 }
181 
182 /*******************************************************************************
183  *
184  * Function         gatt_profile_clcb_alloc
185  *
186  * Description      The function allocates a GATT profile connection link
187  *                  control block
188  *
189  * Returns          NULL if not found. Otherwise pointer to the connection link
190  *                  block.
191  *
192  ******************************************************************************/
gatt_profile_clcb_alloc(tCONN_ID conn_id,const RawAddress & bda,tBT_TRANSPORT tranport)193 static tGATT_PROFILE_CLCB* gatt_profile_clcb_alloc(tCONN_ID conn_id, const RawAddress& bda,
194                                                    tBT_TRANSPORT tranport) {
195   uint8_t i_clcb = 0;
196   tGATT_PROFILE_CLCB* p_clcb = NULL;
197 
198   for (i_clcb = 0, p_clcb = gatt_cb.profile_clcb; i_clcb < GATT_MAX_APPS; i_clcb++, p_clcb++) {
199     if (!p_clcb->in_use) {
200       p_clcb->in_use = true;
201       p_clcb->conn_id = conn_id;
202       p_clcb->connected = true;
203       p_clcb->transport = tranport;
204       p_clcb->bda = bda;
205       break;
206     }
207   }
208   if (i_clcb < GATT_MAX_APPS) {
209     return p_clcb;
210   }
211 
212   return NULL;
213 }
214 
215 /*******************************************************************************
216  *
217  * Function         gatt_profile_clcb_dealloc
218  *
219  * Description      The function deallocates a GATT profile connection link
220  *                  control block
221  *
222  * Returns          void
223  *
224  ******************************************************************************/
gatt_profile_clcb_dealloc(tGATT_PROFILE_CLCB * p_clcb)225 static void gatt_profile_clcb_dealloc(tGATT_PROFILE_CLCB* p_clcb) {
226   memset(p_clcb, 0, sizeof(tGATT_PROFILE_CLCB));
227 }
228 
229 /** GAP Attributes Database Request callback */
read_attr_value(tCONN_ID conn_id,uint16_t handle,tGATT_VALUE * p_value,bool is_long)230 static tGATT_STATUS read_attr_value(tCONN_ID conn_id, uint16_t handle, tGATT_VALUE* p_value,
231                                     bool is_long) {
232   uint8_t* p = p_value->value;
233 
234   if (handle == gatt_cb.handle_sr_supported_feat) {
235     /* GATT_UUID_SERVER_SUP_FEAT*/
236     if (is_long) {
237       return GATT_NOT_LONG;
238     }
239 
240     UINT8_TO_STREAM(p, gatt_cb.gatt_svr_supported_feat_mask);
241     p_value->len = sizeof(gatt_cb.gatt_svr_supported_feat_mask);
242     return GATT_SUCCESS;
243   }
244 
245   if (handle == gatt_cb.handle_cl_supported_feat) {
246     /*GATT_UUID_CLIENT_SUP_FEAT */
247     if (is_long) {
248       return GATT_NOT_LONG;
249     }
250 
251     return gatt_sr_read_cl_supp_feat(conn_id, p_value);
252   }
253 
254   if (handle == gatt_cb.handle_of_database_hash) {
255     /* GATT_UUID_DATABASE_HASH */
256     if (is_long) {
257       return GATT_NOT_LONG;
258     }
259 
260     return gatt_sr_read_db_hash(conn_id, p_value);
261   }
262 
263   if (handle == gatt_cb.handle_of_h_r) {
264     /* GATT_UUID_GATT_SRV_CHGD */
265     return GATT_READ_NOT_PERMIT;
266   }
267 
268   return GATT_NOT_FOUND;
269 }
270 
271 /** GAP Attributes Database Read/Read Blob Request process */
proc_read_req(tCONN_ID conn_id,tGATTS_REQ_TYPE,tGATT_READ_REQ * p_data,tGATTS_RSP * p_rsp)272 static tGATT_STATUS proc_read_req(tCONN_ID conn_id, tGATTS_REQ_TYPE, tGATT_READ_REQ* p_data,
273                                   tGATTS_RSP* p_rsp) {
274   if (p_data->is_long) {
275     p_rsp->attr_value.offset = p_data->offset;
276   }
277 
278   p_rsp->attr_value.handle = p_data->handle;
279 
280   return read_attr_value(conn_id, p_data->handle, &p_rsp->attr_value, p_data->is_long);
281 }
282 
283 /** GAP ATT server process a write request */
proc_write_req(tCONN_ID conn_id,tGATTS_REQ_TYPE,tGATT_WRITE_REQ * p_data)284 static tGATT_STATUS proc_write_req(tCONN_ID conn_id, tGATTS_REQ_TYPE, tGATT_WRITE_REQ* p_data) {
285   uint16_t handle = p_data->handle;
286 
287   /* GATT_UUID_SERVER_SUP_FEAT*/
288   if (handle == gatt_cb.handle_sr_supported_feat) {
289     return GATT_WRITE_NOT_PERMIT;
290   }
291 
292   /* GATT_UUID_CLIENT_SUP_FEAT*/
293   if (handle == gatt_cb.handle_cl_supported_feat) {
294     return gatt_sr_write_cl_supp_feat(conn_id, p_data);
295   }
296 
297   /* GATT_UUID_DATABASE_HASH */
298   if (handle == gatt_cb.handle_of_database_hash) {
299     return GATT_WRITE_NOT_PERMIT;
300   }
301 
302   /* GATT_UUID_GATT_SRV_CHGD */
303   if (handle == gatt_cb.handle_of_h_r) {
304     return GATT_WRITE_NOT_PERMIT;
305   }
306 
307   return GATT_NOT_FOUND;
308 }
309 
310 /*******************************************************************************
311  *
312  * Function         gatt_request_cback
313  *
314  * Description      GATT profile attribute access request callback.
315  *
316  * Returns          void.
317  *
318  ******************************************************************************/
gatt_request_cback(tCONN_ID conn_id,uint32_t trans_id,tGATTS_REQ_TYPE type,tGATTS_DATA * p_data)319 static void gatt_request_cback(tCONN_ID conn_id, uint32_t trans_id, tGATTS_REQ_TYPE type,
320                                tGATTS_DATA* p_data) {
321   tGATT_STATUS status = GATT_INVALID_PDU;
322   tGATTS_RSP rsp_msg;
323   bool rsp_needed = true;
324 
325   memset(&rsp_msg, 0, sizeof(tGATTS_RSP));
326 
327   switch (type) {
328     case GATTS_REQ_TYPE_READ_CHARACTERISTIC:
329     case GATTS_REQ_TYPE_READ_DESCRIPTOR:
330       status = proc_read_req(conn_id, type, &p_data->read_req, &rsp_msg);
331       break;
332 
333     case GATTS_REQ_TYPE_WRITE_CHARACTERISTIC:
334     case GATTS_REQ_TYPE_WRITE_DESCRIPTOR:
335     case GATTS_REQ_TYPE_WRITE_EXEC:
336     case GATT_CMD_WRITE:
337       if (!p_data->write_req.need_rsp) {
338         rsp_needed = false;
339       }
340 
341       status = proc_write_req(conn_id, type, &p_data->write_req);
342       break;
343 
344     case GATTS_REQ_TYPE_MTU:
345       log::verbose("Get MTU exchange new mtu size: {}", p_data->mtu);
346       rsp_needed = false;
347       break;
348 
349     default:
350       log::verbose("Unknown/unexpected LE GAP ATT request: 0x{:x}", type);
351       break;
352   }
353 
354   if (rsp_needed) {
355     if (GATTS_SendRsp(conn_id, trans_id, status, &rsp_msg) != GATT_SUCCESS) {
356       log::warn("Unable to send GATT server response conn_id:{}", conn_id);
357     }
358   }
359 }
360 
361 /*******************************************************************************
362  *
363  * Function         gatt_connect_cback
364  *
365  * Description      Gatt profile connection callback.
366  *
367  * Returns          void
368  *
369  ******************************************************************************/
gatt_connect_cback(tGATT_IF,const RawAddress & bda,tCONN_ID conn_id,bool connected,tGATT_DISCONN_REASON,tBT_TRANSPORT transport)370 static void gatt_connect_cback(tGATT_IF /* gatt_if */, const RawAddress& bda, tCONN_ID conn_id,
371                                bool connected, tGATT_DISCONN_REASON /* reason */,
372                                tBT_TRANSPORT transport) {
373   log::verbose("from {} connected: {}, conn_id: 0x{:x}", bda, connected, conn_id);
374 
375   // if the device is not trusted, remove data when the link is disconnected
376   if (!connected && !btm_sec_is_a_bonded_dev(bda)) {
377     log::info("remove untrusted client status, bda={}", bda);
378     btif_storage_remove_gatt_cl_supp_feat(bda);
379     btif_storage_remove_gatt_cl_db_hash(bda);
380   }
381 
382   tGATT_PROFILE_CLCB* p_clcb = gatt_profile_find_clcb_by_bd_addr(bda, transport);
383   if (p_clcb == NULL) {
384     return;
385   }
386 
387   if (connected) {
388     p_clcb->conn_id = conn_id;
389     p_clcb->connected = true;
390 
391     if (p_clcb->ccc_stage == GATT_SVC_CHANGED_CONNECTING) {
392       p_clcb->ccc_stage++;
393       gatt_cl_start_config_ccc(p_clcb);
394     }
395   } else {
396     gatt_profile_clcb_dealloc(p_clcb);
397   }
398 }
399 
400 /*******************************************************************************
401  *
402  * Function         gatt_profile_db_init
403  *
404  * Description      Initializa the GATT profile attribute database.
405  *
406  ******************************************************************************/
gatt_profile_db_init(void)407 void gatt_profile_db_init(void) {
408   /* Fill our internal UUID with a fixed pattern 0x81 */
409   std::array<uint8_t, Uuid::kNumBytes128> tmp;
410   tmp.fill(0x81);
411 
412   OngoingOps.clear();
413 
414   /* Create a GATT profile service */
415   gatt_cb.gatt_if =
416           GATT_Register(Uuid::From128BitBE(tmp), "GattProfileDb", &gatt_profile_cback, false);
417   GATT_StartIf(gatt_cb.gatt_if);
418 
419   Uuid service_uuid = Uuid::From16Bit(UUID_SERVCLASS_GATT_SERVER);
420 
421   Uuid srv_changed_char_uuid = Uuid::From16Bit(GATT_UUID_GATT_SRV_CHGD);
422   Uuid svr_sup_feat_uuid = Uuid::From16Bit(GATT_UUID_SERVER_SUP_FEAT);
423   Uuid cl_sup_feat_uuid = Uuid::From16Bit(GATT_UUID_CLIENT_SUP_FEAT);
424   Uuid database_hash_uuid = Uuid::From16Bit(GATT_UUID_DATABASE_HASH);
425 
426   btgatt_db_element_t service[] = {
427           {
428                   .uuid = service_uuid,
429                   .type = BTGATT_DB_PRIMARY_SERVICE,
430           },
431           {
432                   .uuid = srv_changed_char_uuid,
433                   .type = BTGATT_DB_CHARACTERISTIC,
434                   .properties = GATT_CHAR_PROP_BIT_INDICATE,
435                   .permissions = 0,
436           },
437           {
438                   .uuid = svr_sup_feat_uuid,
439                   .type = BTGATT_DB_CHARACTERISTIC,
440                   .properties = GATT_CHAR_PROP_BIT_READ,
441                   .permissions = GATT_PERM_READ,
442           },
443           {
444                   .uuid = cl_sup_feat_uuid,
445                   .type = BTGATT_DB_CHARACTERISTIC,
446                   .properties = GATT_CHAR_PROP_BIT_READ | GATT_CHAR_PROP_BIT_WRITE,
447                   .permissions = GATT_PERM_READ | GATT_PERM_WRITE,
448           },
449           {
450                   .uuid = database_hash_uuid,
451                   .type = BTGATT_DB_CHARACTERISTIC,
452                   .properties = GATT_CHAR_PROP_BIT_READ,
453                   .permissions = GATT_PERM_READ,
454           }};
455 
456   if (GATTS_AddService(gatt_cb.gatt_if, service, sizeof(service) / sizeof(btgatt_db_element_t)) !=
457       GATT_SERVICE_STARTED) {
458     log::warn("Unable to add GATT server service gatt_if:{}", gatt_cb.gatt_if);
459   }
460 
461   gatt_cb.handle_of_h_r = service[1].attribute_handle;
462   gatt_cb.handle_sr_supported_feat = service[2].attribute_handle;
463   gatt_cb.handle_cl_supported_feat = service[3].attribute_handle;
464   gatt_cb.handle_of_database_hash = service[4].attribute_handle;
465 
466   gatt_cb.gatt_svr_supported_feat_mask |= BLE_GATT_SVR_SUP_FEAT_EATT_BITMASK;
467   gatt_cb.gatt_cl_supported_feat_mask |= BLE_GATT_CL_ANDROID_SUP_FEAT;
468   gatt_cb.gatt_cl_supported_feat_mask |= BLE_GATT_CL_SUP_FEAT_CACHING_BITMASK;
469 
470   log::verbose("gatt_if={} EATT supported", gatt_cb.gatt_if);
471 }
472 
473 /*******************************************************************************
474  *
475  * Function         gatt_disc_res_cback
476  *
477  * Description      Gatt profile discovery result callback
478  *
479  * Returns          void
480  *
481  ******************************************************************************/
gatt_disc_res_cback(tCONN_ID conn_id,tGATT_DISC_TYPE disc_type,tGATT_DISC_RES * p_data)482 static void gatt_disc_res_cback(tCONN_ID conn_id, tGATT_DISC_TYPE disc_type,
483                                 tGATT_DISC_RES* p_data) {
484   tGATT_PROFILE_CLCB* p_clcb = gatt_profile_find_clcb_by_conn_id(conn_id);
485 
486   if (p_clcb == NULL) {
487     return;
488   }
489 
490   switch (disc_type) {
491     case GATT_DISC_SRVC_BY_UUID: /* stage 1 */
492       p_clcb->e_handle = p_data->value.group_value.e_handle;
493       p_clcb->ccc_result++;
494       break;
495 
496     case GATT_DISC_CHAR: /* stage 2 */
497       p_clcb->s_handle = p_data->value.dclr_value.val_handle;
498       p_clcb->ccc_result++;
499       break;
500 
501     case GATT_DISC_CHAR_DSCPT: /* stage 3 */
502       if (p_data->type == Uuid::From16Bit(GATT_UUID_CHAR_CLIENT_CONFIG)) {
503         p_clcb->s_handle = p_data->handle;
504         p_clcb->ccc_result++;
505       }
506       break;
507 
508     case GATT_DISC_SRVC_ALL:
509     case GATT_DISC_INC_SRVC:
510     case GATT_DISC_MAX:
511       log::error("Illegal discovery item handled");
512       break;
513   }
514 }
515 
516 /*******************************************************************************
517  *
518  * Function         gatt_disc_cmpl_cback
519  *
520  * Description      Gatt profile discovery complete callback
521  *
522  * Returns          void
523  *
524  ******************************************************************************/
gatt_disc_cmpl_cback(tCONN_ID conn_id,tGATT_DISC_TYPE,tGATT_STATUS status)525 static void gatt_disc_cmpl_cback(tCONN_ID conn_id, tGATT_DISC_TYPE /* disc_type */,
526                                  tGATT_STATUS status) {
527   tGATT_PROFILE_CLCB* p_clcb = gatt_profile_find_clcb_by_conn_id(conn_id);
528   if (p_clcb == NULL) {
529     log::warn("Unable to find gatt profile after discovery complete");
530     return;
531   }
532 
533   if (status != GATT_SUCCESS) {
534     log::warn("Gatt discovery completed with errors status:{}", status);
535     return;
536   }
537   if (p_clcb->ccc_result == 0) {
538     log::warn("Gatt discovery completed but connection was idle id:{}", conn_id);
539     return;
540   }
541 
542   p_clcb->ccc_result = 0;
543   p_clcb->ccc_stage++;
544   gatt_cl_start_config_ccc(p_clcb);
545 }
546 
gatt_svc_read_cl_supp_feat_req(tCONN_ID conn_id)547 static bool gatt_svc_read_cl_supp_feat_req(tCONN_ID conn_id) {
548   tGATT_READ_PARAM param;
549 
550   memset(&param, 0, sizeof(tGATT_READ_PARAM));
551 
552   param.service.s_handle = 1;
553   param.service.e_handle = 0xFFFF;
554   param.service.auth_req = 0;
555 
556   param.service.uuid = bluetooth::Uuid::From16Bit(GATT_UUID_CLIENT_SUP_FEAT);
557 
558   tGATT_STATUS status = GATTC_Read(conn_id, GATT_READ_BY_TYPE, &param);
559   if (status != GATT_SUCCESS) {
560     log::error("Read failed. Status: 0x{:x}", static_cast<uint8_t>(status));
561     return false;
562   }
563 
564   gatt_op_cb_data cb_data;
565 
566   cb_data.cb =
567           base::BindOnce([](const RawAddress& /* bdaddr */, uint8_t /* support */) { return; });
568   cb_data.op_uuid = GATT_UUID_CLIENT_SUP_FEAT;
569   OngoingOps[conn_id].emplace_back(std::move(cb_data));
570 
571   return true;
572 }
573 
gatt_att_write_cl_supp_feat(tCONN_ID conn_id,uint16_t handle)574 static bool gatt_att_write_cl_supp_feat(tCONN_ID conn_id, uint16_t handle) {
575   tGATT_VALUE attr;
576 
577   memset(&attr, 0, sizeof(tGATT_VALUE));
578 
579   attr.conn_id = conn_id;
580   attr.handle = handle;
581   attr.len = 1;
582   attr.value[0] = gatt_cb.gatt_cl_supported_feat_mask;
583 
584   tGATT_STATUS status = GATTC_Write(conn_id, GATT_WRITE, &attr);
585   if (status != GATT_SUCCESS) {
586     log::error("Write failed. Status: 0x{:x}", static_cast<uint8_t>(status));
587     return false;
588   }
589 
590   return true;
591 }
592 
593 /*******************************************************************************
594  *
595  * Function         gatt_cl_op_cmpl_cback
596  *
597  * Description      Gatt profile client operation complete callback
598  *
599  * Returns          void
600  *
601  ******************************************************************************/
gatt_cl_op_cmpl_cback(tCONN_ID conn_id,tGATTC_OPTYPE op,tGATT_STATUS status,tGATT_CL_COMPLETE * p_data)602 static void gatt_cl_op_cmpl_cback(tCONN_ID conn_id, tGATTC_OPTYPE op, tGATT_STATUS status,
603                                   tGATT_CL_COMPLETE* p_data) {
604   auto iter = OngoingOps.find(conn_id);
605 
606   log::verbose("opcode: 0x{:x} status: {} conn id: 0x{:x}", static_cast<uint8_t>(op), status,
607                static_cast<int>(conn_id));
608 
609   if (op != GATTC_OPTYPE_READ && op != GATTC_OPTYPE_WRITE) {
610     log::verbose("Not interested in opcode {}", op);
611     return;
612   }
613 
614   if (iter == OngoingOps.end() || (iter->second.size() == 0)) {
615     /* If OngoingOps is empty it means we are not interested in the result here.
616      */
617     log::debug("Unexpected read complete");
618     return;
619   }
620 
621   uint16_t cl_op_uuid = iter->second.front().op_uuid;
622 
623   if (op == GATTC_OPTYPE_WRITE) {
624     if (cl_op_uuid == GATT_UUID_GATT_SRV_CHGD) {
625       log::debug("Write response from Service Changed CCC");
626       iter->second.pop_front();
627       /* Read server supported features here supported */
628       read_sr_supported_feat_req(conn_id, base::BindOnce([](const RawAddress& /* bdaddr */,
629                                                             uint8_t /* support */) { return; }));
630     } else {
631       log::debug("Not interested in that write response");
632     }
633     return;
634   }
635 
636   /* Handle Read operations */
637   uint8_t* pp = p_data->att_value.value;
638 
639   log::verbose("cl_op_uuid 0x{:x}", cl_op_uuid);
640 
641   switch (cl_op_uuid) {
642     case GATT_UUID_SERVER_SUP_FEAT: {
643       uint8_t tcb_idx = gatt_get_tcb_idx(conn_id);
644       tGATT_TCB& tcb = gatt_cb.tcb[tcb_idx];
645 
646       auto operation_callback_data = std::move(iter->second.front());
647       iter->second.pop_front();
648 
649       /* Check if EATT is supported */
650       if (status == GATT_SUCCESS) {
651         STREAM_TO_UINT8(tcb.sr_supp_feat, pp);
652         btif_storage_set_gatt_sr_supp_feat(tcb.peer_bda, tcb.sr_supp_feat);
653       }
654 
655       /* Notify user about the supported features */
656       std::move(operation_callback_data.cb).Run(tcb.peer_bda, tcb.sr_supp_feat);
657 
658       /* If server supports EATT lets try to find handle for the
659        * client supported features characteristic, where we could write
660        * our supported features as a client.
661        */
662       if (tcb.sr_supp_feat & BLE_GATT_SVR_SUP_FEAT_EATT_BITMASK) {
663         gatt_svc_read_cl_supp_feat_req(conn_id);
664       }
665 
666       break;
667     }
668     case GATT_UUID_CSIS_SIRK: {
669       uint8_t tcb_idx = gatt_get_tcb_idx(conn_id);
670       tGATT_TCB& tcb = gatt_cb.tcb[tcb_idx];
671 
672       auto operation_callback_data = std::move(iter->second.front());
673       iter->second.pop_front();
674       tcb.gatt_status = status;
675 
676       if (status == GATT_SUCCESS) {
677         STREAM_TO_UINT8(tcb.sirk_type, pp);
678         STREAM_TO_ARRAY(tcb.sirk.data(), pp, 16);
679       }
680 
681       std::move(operation_callback_data.sirk_cb)
682               .Run(tcb.gatt_status, tcb.peer_bda, tcb.sirk_type, tcb.sirk);
683 
684       break;
685     }
686     case GATT_UUID_CLIENT_SUP_FEAT:
687       /*We don't need callback data anymore */
688       iter->second.pop_front();
689 
690       if (status != GATT_SUCCESS) {
691         log::info("Client supported features charcteristic not found");
692         return;
693       }
694 
695       /* Write our client supported features to the remote device */
696       gatt_att_write_cl_supp_feat(conn_id, p_data->att_value.handle);
697       break;
698   }
699 }
700 
701 /*******************************************************************************
702  *
703  * Function         gatt_cl_start_config_ccc
704  *
705  * Description      Gatt profile start configure service change CCC
706  *
707  * Returns          void
708  *
709  ******************************************************************************/
gatt_cl_start_config_ccc(tGATT_PROFILE_CLCB * p_clcb)710 static void gatt_cl_start_config_ccc(tGATT_PROFILE_CLCB* p_clcb) {
711   log::verbose("stage: {}", p_clcb->ccc_stage);
712 
713   switch (p_clcb->ccc_stage) {
714     case GATT_SVC_CHANGED_SERVICE: /* discover GATT service */
715       if (GATTC_Discover(p_clcb->conn_id, GATT_DISC_SRVC_BY_UUID, 0x0001, 0xffff,
716                          Uuid::From16Bit(UUID_SERVCLASS_GATT_SERVER)) != GATT_SUCCESS) {
717         log::warn("Unable to discovery GATT client conn_id:{}", p_clcb->conn_id);
718       }
719       break;
720 
721     case GATT_SVC_CHANGED_CHARACTERISTIC: /* discover service change char */
722       if (GATTC_Discover(p_clcb->conn_id, GATT_DISC_CHAR, 0x0001, p_clcb->e_handle,
723                          Uuid::From16Bit(GATT_UUID_GATT_SRV_CHGD)) != GATT_SUCCESS) {
724         log::warn("Unable to discovery GATT client conn_id:{}", p_clcb->conn_id);
725       }
726       break;
727 
728     case GATT_SVC_CHANGED_DESCRIPTOR: /* discover service change ccc */
729       if (GATTC_Discover(p_clcb->conn_id, GATT_DISC_CHAR_DSCPT, p_clcb->s_handle,
730                          p_clcb->e_handle) != GATT_SUCCESS) {
731         log::warn("Unable to discovery GATT client conn_id:{}", p_clcb->conn_id);
732       }
733       break;
734 
735     case GATT_SVC_CHANGED_CONFIGURE_CCCD: /* write ccc */
736     {
737       tGATT_VALUE ccc_value;
738       memset(&ccc_value, 0, sizeof(tGATT_VALUE));
739       ccc_value.handle = p_clcb->s_handle;
740       ccc_value.len = 2;
741       ccc_value.value[0] = GATT_CLT_CONFIG_INDICATION;
742       if (GATTC_Write(p_clcb->conn_id, GATT_WRITE, &ccc_value) != GATT_SUCCESS) {
743         log::warn("Unable to write GATT client data conn_id:{}", p_clcb->conn_id);
744       }
745 
746       gatt_op_cb_data cb_data;
747       cb_data.cb =
748               base::BindOnce([](const RawAddress& /* bdaddr */, uint8_t /* support */) { return; });
749       cb_data.op_uuid = GATT_UUID_GATT_SRV_CHGD;
750       OngoingOps[p_clcb->conn_id].emplace_back(std::move(cb_data));
751 
752       break;
753     }
754   }
755 }
756 
757 /*******************************************************************************
758  *
759  * Function         GATT_ConfigServiceChangeCCC
760  *
761  * Description      Configure service change indication on remote device
762  *
763  * Returns          none
764  *
765  ******************************************************************************/
GATT_ConfigServiceChangeCCC(const RawAddress & remote_bda,bool,tBT_TRANSPORT transport)766 void GATT_ConfigServiceChangeCCC(const RawAddress& remote_bda, bool /* enable */,
767                                  tBT_TRANSPORT transport) {
768   tGATT_PROFILE_CLCB* p_clcb = gatt_profile_find_clcb_by_bd_addr(remote_bda, transport);
769 
770   if (p_clcb == NULL) {
771     p_clcb = gatt_profile_clcb_alloc(0, remote_bda, transport);
772   }
773 
774   if (p_clcb == NULL) {
775     return;
776   }
777 
778   if (GATT_GetConnIdIfConnected(gatt_cb.gatt_if, remote_bda, &p_clcb->conn_id, transport)) {
779     p_clcb->connected = true;
780   } else {
781     log::warn(
782             "Unable to get GATT connection id if connected peer:{} gatt_if:{} "
783             "transport:{}",
784             remote_bda, gatt_cb.gatt_if, bt_transport_text(BT_TRANSPORT_LE));
785   }
786 
787   /* hold the link here */
788   if (!GATT_Connect(gatt_cb.gatt_if, remote_bda, BTM_BLE_DIRECT_CONNECTION, transport, true)) {
789     log::warn(
790             "Unable to connect GATT client gatt_if:{} peer:{} transport:{} "
791             "connection_tyoe:{} opporunistic:{}",
792             gatt_cb.gatt_if, remote_bda, bt_transport_text(transport), "BTM_BLE_DIRECT_CONNECTION",
793             true);
794   }
795   p_clcb->ccc_stage = GATT_SVC_CHANGED_CONNECTING;
796 
797   if (!p_clcb->connected) {
798     /* wait for connection */
799     return;
800   }
801 
802   p_clcb->ccc_stage++;
803   gatt_cl_start_config_ccc(p_clcb);
804 }
805 
806 /*******************************************************************************
807  *
808  * Function         gatt_cl_init_sr_status
809  *
810  * Description      Restore status for trusted GATT Server device
811  *
812  * Returns          none
813  *
814  ******************************************************************************/
gatt_cl_init_sr_status(tGATT_TCB & tcb)815 void gatt_cl_init_sr_status(tGATT_TCB& tcb) {
816   tcb.sr_supp_feat = btif_storage_get_sr_supp_feat(tcb.peer_bda);
817 
818   if (tcb.sr_supp_feat & BLE_GATT_SVR_SUP_FEAT_EATT_BITMASK) {
819     bluetooth::eatt::EattExtension::AddFromStorage(tcb.peer_bda);
820   }
821 }
822 
read_sr_supported_feat_req(tCONN_ID conn_id,base::OnceCallback<void (const RawAddress &,uint8_t)> cb)823 static bool read_sr_supported_feat_req(tCONN_ID conn_id,
824                                        base::OnceCallback<void(const RawAddress&, uint8_t)> cb) {
825   tGATT_READ_PARAM param = {};
826 
827   param.service.s_handle = 1;
828   param.service.e_handle = 0xFFFF;
829   param.service.auth_req = 0;
830 
831   param.service.uuid = bluetooth::Uuid::From16Bit(GATT_UUID_SERVER_SUP_FEAT);
832 
833   if (GATTC_Read(conn_id, GATT_READ_BY_TYPE, &param) != GATT_SUCCESS) {
834     log::error("Read GATT Support features GATT_Read Failed");
835     return false;
836   }
837 
838   gatt_op_cb_data cb_data;
839 
840   cb_data.cb = std::move(cb);
841   cb_data.op_uuid = GATT_UUID_SERVER_SUP_FEAT;
842   OngoingOps[conn_id].emplace_back(std::move(cb_data));
843 
844   return true;
845 }
846 
read_sr_sirk_req(tCONN_ID conn_id,base::OnceCallback<void (tGATT_STATUS status,const RawAddress &,uint8_t sirk_type,Octet16 & sirk)> cb)847 static bool read_sr_sirk_req(tCONN_ID conn_id,
848                              base::OnceCallback<void(tGATT_STATUS status, const RawAddress&,
849                                                      uint8_t sirk_type, Octet16& sirk)>
850                                      cb) {
851   tGATT_READ_PARAM param = {};
852   tBLE_ADDR_TYPE address_type = BLE_ADDR_PUBLIC;
853 
854   param.service.s_handle = 1;
855   param.service.e_handle = 0xFFFF;
856   param.service.auth_req = 0;
857 
858   param.service.uuid = bluetooth::Uuid::From16Bit(GATT_UUID_CSIS_SIRK);
859 
860   uint8_t tcb_idx = gatt_get_tcb_idx(conn_id);
861   tGATT_TCB& tcb = gatt_cb.tcb[tcb_idx];
862 
863   RawAddress identity_address = tcb.peer_bda;
864 
865   btm_random_pseudo_to_identity_addr(&identity_address, &address_type);
866 
867   if (address_type == BLE_ADDR_PUBLIC &&
868       interop_match_addr(INTEROP_DISABLE_SIRK_READ_BY_TYPE, &identity_address)) {
869     if (GATTC_Read(conn_id, GATT_READ_CHAR_VALUE, &param) != GATT_SUCCESS) {
870       log::error("Read GATT Support features GATT_Read Failed, conn_id: {}",
871                  static_cast<int>(conn_id));
872       return false;
873     }
874   }
875   else{
876     if (GATTC_Read(conn_id, GATT_READ_BY_TYPE, &param) != GATT_SUCCESS) {
877       log::error("Read GATT Support features GATT_Read Failed, conn_id: {}",
878                  static_cast<int>(conn_id));
879       return false;
880     }
881   }
882 
883   gatt_op_cb_data cb_data;
884 
885   cb_data.sirk_cb = std::move(cb);
886   cb_data.op_uuid = GATT_UUID_CSIS_SIRK;
887   OngoingOps[conn_id].emplace_back(std::move(cb_data));
888 
889   return true;
890 }
891 
892 /*******************************************************************************
893  *
894  * Function         gatt_cl_read_sr_supp_feat_req
895  *
896  * Description      Read remote device supported GATT feature mask.
897  *
898  * Returns          bool
899  *
900  ******************************************************************************/
gatt_cl_read_sr_supp_feat_req(const RawAddress & peer_bda,base::OnceCallback<void (const RawAddress &,uint8_t)> cb)901 bool gatt_cl_read_sr_supp_feat_req(const RawAddress& peer_bda,
902                                    base::OnceCallback<void(const RawAddress&, uint8_t)> cb) {
903   tGATT_PROFILE_CLCB* p_clcb;
904   tCONN_ID conn_id;
905 
906   if (!cb) {
907     return false;
908   }
909 
910   log::verbose("BDA: {} read gatt supported features", peer_bda);
911 
912   if (!GATT_GetConnIdIfConnected(gatt_cb.gatt_if, peer_bda, &conn_id, BT_TRANSPORT_LE)) {
913     log::warn(
914             "Unable to get GATT connection id if connected peer:{} gatt_if:{} "
915             "transport:{}",
916             peer_bda, gatt_cb.gatt_if, bt_transport_text(BT_TRANSPORT_LE));
917   }
918 
919   if (conn_id == GATT_INVALID_CONN_ID) {
920     return false;
921   }
922 
923   p_clcb = gatt_profile_find_clcb_by_conn_id(conn_id);
924   if (!p_clcb) {
925     p_clcb = gatt_profile_clcb_alloc(conn_id, peer_bda, BT_TRANSPORT_LE);
926   }
927 
928   if (!p_clcb) {
929     log::verbose("p_clcb is NULL 0x{:x}", conn_id);
930     return false;
931   }
932 
933   auto it = OngoingOps.find(conn_id);
934   if (it == OngoingOps.end()) {
935     OngoingOps[conn_id] = std::deque<gatt_op_cb_data>();
936   }
937 
938   return read_sr_supported_feat_req(conn_id, std::move(cb));
939 }
940 
941 /*******************************************************************************
942  *
943  * Function         gatt_cl_read_sirk_req
944  *
945  * Description      Read remote SIRK if it's a set member device.
946  *
947  * Returns          bool
948  *
949  ******************************************************************************/
gatt_cl_read_sirk_req(const RawAddress & peer_bda,base::OnceCallback<void (tGATT_STATUS status,const RawAddress &,uint8_t sirk_type,Octet16 & sirk)> cb)950 bool gatt_cl_read_sirk_req(const RawAddress& peer_bda,
951                            base::OnceCallback<void(tGATT_STATUS status, const RawAddress&,
952                                                    uint8_t sirk_type, Octet16& sirk)>
953                                    cb) {
954   tGATT_PROFILE_CLCB* p_clcb;
955   tCONN_ID conn_id;
956 
957   if (!cb) {
958     return false;
959   }
960 
961   log::debug("BDA: {}, read SIRK", peer_bda);
962 
963   if (!GATT_GetConnIdIfConnected(gatt_cb.gatt_if, peer_bda, &conn_id, BT_TRANSPORT_LE)) {
964     log::warn(
965             "Unable to get GATT connection id if connected peer:{} gatt_if:{} "
966             "transport:{}",
967             peer_bda, gatt_cb.gatt_if, bt_transport_text(BT_TRANSPORT_LE));
968   }
969   if (conn_id == GATT_INVALID_CONN_ID) {
970     return false;
971   }
972 
973   p_clcb = gatt_profile_find_clcb_by_conn_id(conn_id);
974   if (!p_clcb) {
975     p_clcb = gatt_profile_clcb_alloc(conn_id, peer_bda, BT_TRANSPORT_LE);
976   }
977 
978   if (!p_clcb) {
979     log::verbose("p_clcb is NULL, conn_id: {:04x}", conn_id);
980     return false;
981   }
982 
983   auto it = OngoingOps.find(conn_id);
984 
985   if (it == OngoingOps.end()) {
986     OngoingOps[conn_id] = std::deque<gatt_op_cb_data>();
987   }
988 
989   return read_sr_sirk_req(conn_id, std::move(cb));
990 }
991 
992 /*******************************************************************************
993  *
994  * Function         gatt_profile_get_eatt_support
995  *
996  * Description      Check if EATT is supported with remote device.
997  *
998  * Returns          if EATT is supported.
999  *
1000  ******************************************************************************/
gatt_profile_get_eatt_support(const RawAddress & remote_bda)1001 bool gatt_profile_get_eatt_support(const RawAddress& remote_bda) {
1002   tCONN_ID conn_id;
1003 
1004   log::verbose("BDA: {} read GATT support", remote_bda);
1005 
1006   if (!GATT_GetConnIdIfConnected(gatt_cb.gatt_if, remote_bda, &conn_id, BT_TRANSPORT_LE)) {
1007     log::warn(
1008             "Unable to get GATT connection id if connected peer:{} gatt_if:{} "
1009             "transport:{}",
1010             remote_bda, gatt_cb.gatt_if, bt_transport_text(BT_TRANSPORT_LE));
1011   }
1012 
1013   /* This read is important only when connected */
1014   if (conn_id == GATT_INVALID_CONN_ID) {
1015     return false;
1016   }
1017 
1018   return gatt_profile_get_eatt_support_by_conn_id(conn_id);
1019 }
1020 
gatt_profile_get_eatt_support_by_conn_id(tCONN_ID conn_id)1021 bool gatt_profile_get_eatt_support_by_conn_id(tCONN_ID conn_id) {
1022   /* Get tcb info */
1023   uint8_t tcb_idx = gatt_get_tcb_idx(conn_id);
1024   tGATT_TCB& tcb = gatt_cb.tcb[tcb_idx];
1025   return tcb.sr_supp_feat & BLE_GATT_SVR_SUP_FEAT_EATT_BITMASK;
1026 }
1027 
1028 /*******************************************************************************
1029  *
1030  * Function         gatt_sr_is_robust_caching_enabled
1031  *
1032  * Description      Check if Robust Caching is enabled on server side.
1033  *
1034  * Returns          true if enabled in gd flag, otherwise false
1035  *
1036  ******************************************************************************/
gatt_sr_is_robust_caching_enabled()1037 static bool gatt_sr_is_robust_caching_enabled() { return false; }
1038 
1039 /*******************************************************************************
1040  *
1041  * Function         gatt_sr_is_cl_robust_caching_supported
1042  *
1043  * Description      Check if Robust Caching is supported for the connection
1044  *
1045  * Returns          true if enabled by client side, otherwise false
1046  *
1047  ******************************************************************************/
gatt_sr_is_cl_robust_caching_supported(tGATT_TCB & tcb)1048 static bool gatt_sr_is_cl_robust_caching_supported(tGATT_TCB& tcb) {
1049   // if robust caching is not enabled, should always return false
1050   if (!gatt_sr_is_robust_caching_enabled()) {
1051     return false;
1052   }
1053   return tcb.cl_supp_feat & BLE_GATT_CL_SUP_FEAT_CACHING_BITMASK;
1054 }
1055 
1056 /*******************************************************************************
1057  *
1058  * Function         gatt_sr_is_cl_multi_variable_len_notif_supported
1059  *
1060  * Description      Check if Multiple Variable Length Notifications
1061  *                  supported for the connection
1062  *
1063  * Returns          true if enabled by client side, otherwise false
1064  *
1065  ******************************************************************************/
gatt_sr_is_cl_multi_variable_len_notif_supported(tGATT_TCB & tcb)1066 bool gatt_sr_is_cl_multi_variable_len_notif_supported(tGATT_TCB& tcb) {
1067   return tcb.cl_supp_feat & BLE_GATT_CL_SUP_FEAT_MULTI_NOTIF_BITMASK;
1068 }
1069 
1070 /*******************************************************************************
1071  *
1072  * Function         gatt_sr_is_cl_change_aware
1073  *
1074  * Description      Check if the connection is change-aware
1075  *
1076  * Returns          true if change aware, otherwise false
1077  *
1078  ******************************************************************************/
gatt_sr_is_cl_change_aware(tGATT_TCB & tcb)1079 bool gatt_sr_is_cl_change_aware(tGATT_TCB& tcb) {
1080   // if robust caching is not supported, should always return true by default
1081   if (!gatt_sr_is_cl_robust_caching_supported(tcb)) {
1082     return true;
1083   }
1084   return tcb.is_robust_cache_change_aware;
1085 }
1086 
1087 /*******************************************************************************
1088  *
1089  * Function         gatt_sr_init_cl_status
1090  *
1091  * Description      Restore status for trusted device
1092  *
1093  * Returns          none
1094  *
1095  ******************************************************************************/
gatt_sr_init_cl_status(tGATT_TCB & tcb)1096 void gatt_sr_init_cl_status(tGATT_TCB& tcb) {
1097   tcb.cl_supp_feat = btif_storage_get_gatt_cl_supp_feat(tcb.peer_bda);
1098   // This is used to reset bit when robust caching is disabled
1099   if (!gatt_sr_is_robust_caching_enabled()) {
1100     tcb.cl_supp_feat &= ~BLE_GATT_CL_SUP_FEAT_CACHING_BITMASK;
1101   }
1102 
1103   if (gatt_sr_is_cl_robust_caching_supported(tcb)) {
1104     Octet16 stored_hash = btif_storage_get_gatt_cl_db_hash(tcb.peer_bda);
1105     tcb.is_robust_cache_change_aware = (stored_hash == gatt_cb.database_hash);
1106   } else {
1107     // set default value for untrusted device
1108     tcb.is_robust_cache_change_aware = true;
1109   }
1110 
1111   log::info("bda={}, cl_supp_feat=0x{:x}, aware={}", tcb.peer_bda, tcb.cl_supp_feat,
1112             tcb.is_robust_cache_change_aware);
1113 }
1114 
1115 /*******************************************************************************
1116  *
1117  * Function         gatt_sr_update_cl_status
1118  *
1119  * Description      Update change-aware status for the remote device
1120  *
1121  * Returns          none
1122  *
1123  ******************************************************************************/
gatt_sr_update_cl_status(tGATT_TCB & tcb,bool chg_aware)1124 void gatt_sr_update_cl_status(tGATT_TCB& tcb, bool chg_aware) {
1125   // if robust caching is not supported, do nothing
1126   if (!gatt_sr_is_cl_robust_caching_supported(tcb)) {
1127     return;
1128   }
1129 
1130   // only when client status is changed from change-unaware to change-aware, we
1131   // can then store database hash into btif_storage
1132   if (!tcb.is_robust_cache_change_aware && chg_aware) {
1133     btif_storage_set_gatt_cl_db_hash(tcb.peer_bda, gatt_cb.database_hash);
1134   }
1135 
1136   // only when the status is changed, print the log
1137   if (tcb.is_robust_cache_change_aware != chg_aware) {
1138     log::info("bda={}, chg_aware={}", tcb.peer_bda, chg_aware);
1139   }
1140 
1141   tcb.is_robust_cache_change_aware = chg_aware;
1142 }
1143 
1144 /* handle request for reading database hash */
gatt_sr_read_db_hash(tCONN_ID conn_id,tGATT_VALUE * p_value)1145 static tGATT_STATUS gatt_sr_read_db_hash(tCONN_ID conn_id, tGATT_VALUE* p_value) {
1146   log::info("conn_id=0x{:x}", conn_id);
1147 
1148   uint8_t* p = p_value->value;
1149   Octet16& db_hash = gatt_cb.database_hash;
1150   ARRAY_TO_STREAM(p, db_hash.data(), (uint16_t)db_hash.size());
1151   p_value->len = (uint16_t)db_hash.size();
1152 
1153   // Every time when database hash is requested, reset flag.
1154   uint8_t tcb_idx = gatt_get_tcb_idx(conn_id);
1155   gatt_sr_update_cl_status(gatt_cb.tcb[tcb_idx], /* chg_aware= */ true);
1156   return GATT_SUCCESS;
1157 }
1158 
1159 /* handle request for reading client supported features */
gatt_sr_read_cl_supp_feat(tCONN_ID conn_id,tGATT_VALUE * p_value)1160 static tGATT_STATUS gatt_sr_read_cl_supp_feat(tCONN_ID conn_id, tGATT_VALUE* p_value) {
1161   // Get tcb info
1162   uint8_t tcb_idx = gatt_get_tcb_idx(conn_id);
1163   tGATT_TCB& tcb = gatt_cb.tcb[tcb_idx];
1164 
1165   uint8_t* p = p_value->value;
1166   UINT8_TO_STREAM(p, tcb.cl_supp_feat);
1167   p_value->len = 1;
1168 
1169   return GATT_SUCCESS;
1170 }
1171 
1172 /* handle request for writing client supported features */
gatt_sr_write_cl_supp_feat(tCONN_ID conn_id,tGATT_WRITE_REQ * p_data)1173 static tGATT_STATUS gatt_sr_write_cl_supp_feat(tCONN_ID conn_id, tGATT_WRITE_REQ* p_data) {
1174   std::list<uint8_t> tmp;
1175   uint16_t len = p_data->len;
1176   uint8_t value, *p = p_data->value;
1177   // Read all octets into list
1178   while (len > 0) {
1179     STREAM_TO_UINT8(value, p);
1180     tmp.push_back(value);
1181     len--;
1182   }
1183   // Remove trailing zero octets
1184   while (!tmp.empty()) {
1185     if (tmp.back() != 0x00) {
1186       break;
1187     }
1188     tmp.pop_back();
1189   }
1190 
1191   // Get tcb info
1192   uint8_t tcb_idx = gatt_get_tcb_idx(conn_id);
1193   tGATT_TCB& tcb = gatt_cb.tcb[tcb_idx];
1194 
1195   std::list<uint8_t> feature_list;
1196   feature_list.push_back(tcb.cl_supp_feat);
1197 
1198   // If input length is zero, return value_not_allowed
1199   if (tmp.empty()) {
1200     log::info("zero length, conn_id=0x{:x}, bda={}", conn_id, tcb.peer_bda);
1201     return GATT_VALUE_NOT_ALLOWED;
1202   }
1203   // if original length is longer than new one, it must be the bit reset case.
1204   if (feature_list.size() > tmp.size()) {
1205     log::info("shorter length, conn_id=0x{:x}, bda={}", conn_id, tcb.peer_bda);
1206     return GATT_VALUE_NOT_ALLOWED;
1207   }
1208   // new length is longer or equals to the original, need to check bits
1209   // one by one. Here we use bit-wise operation.
1210   // 1. Use XOR to locate the change bit, val_xor is the change bit mask
1211   // 2. Use AND for val_xor and *it_new to get val_and
1212   // 3. If val_and != val_xor, it means the change is from 1 to 0
1213   auto it_old = feature_list.cbegin();
1214   auto it_new = tmp.cbegin();
1215   for (; it_old != feature_list.cend(); it_old++, it_new++) {
1216     uint8_t val_xor = *it_old ^ *it_new;
1217     uint8_t val_and = val_xor & *it_new;
1218     if (val_and != val_xor) {
1219       log::info("bit cannot be reset, conn_id=0x{:x}, bda={}", conn_id, tcb.peer_bda);
1220       return GATT_VALUE_NOT_ALLOWED;
1221     }
1222   }
1223 
1224   // get current robust caching status before setting new one
1225   bool curr_caching_state = gatt_sr_is_cl_robust_caching_supported(tcb);
1226 
1227   tcb.cl_supp_feat = tmp.front();
1228   if (!gatt_sr_is_robust_caching_enabled()) {
1229     // remove robust caching bit
1230     tcb.cl_supp_feat &= ~BLE_GATT_CL_SUP_FEAT_CACHING_BITMASK;
1231     log::info("reset robust caching bit, conn_id=0x{:x}, bda={}", conn_id, tcb.peer_bda);
1232   }
1233   // TODO(hylo): save data as byte array
1234   btif_storage_set_gatt_cl_supp_feat(tcb.peer_bda, tcb.cl_supp_feat);
1235 
1236   // get new robust caching status after setting new one
1237   bool new_caching_state = gatt_sr_is_cl_robust_caching_supported(tcb);
1238   // only when the first time robust caching request, print the log
1239   if (!curr_caching_state && new_caching_state) {
1240     log::info("robust caching enabled by client, conn_id=0x{:x}", conn_id);
1241   }
1242 
1243   return GATT_SUCCESS;
1244 }
1245