1 /*
2  * Copyright (c) 2023 Nordic Semiconductor ASA
3  *
4  * SPDX-License-Identifier: Apache-2.0
5  */
6 
7 #include "utils.h"
8 #include "argparse.h"
9 #include "bs_pc_backchannel.h"
10 
11 #include <zephyr/kernel.h>
12 #include <zephyr/bluetooth/bluetooth.h>
13 #include <zephyr/bluetooth/gatt.h>
14 #include <zephyr/sys/__assert.h>
15 
16 /* Custom Service Variables */
17 static const struct bt_uuid_128 test_svc_uuid = BT_UUID_INIT_128(
18 	0xf0, 0xde, 0xbc, 0x9a, 0x78, 0x56, 0x34, 0x12,
19 	0x78, 0x56, 0x34, 0x12, 0x78, 0x56, 0x34, 0x12);
20 
21 static const struct bt_uuid_128 test_svc_uuid_2 = BT_UUID_INIT_128(
22 	0xf1, 0xdd, 0xbc, 0x9a, 0x78, 0x56, 0x34, 0x12,
23 	0x78, 0x56, 0x34, 0x12, 0x78, 0x56, 0x34, 0x12);
24 
25 static const struct bt_uuid_128 test_chrc_uuid = BT_UUID_INIT_128(
26 	0xf2, 0xde, 0xbc, 0x9a, 0x78, 0x56, 0x34, 0x12,
27 	0x78, 0x56, 0x34, 0x12, 0x78, 0x56, 0x34, 0x12);
28 
29 static uint8_t test_value[] = { 'T', 'e', 's', 't', '\0' };
30 
31 DEFINE_FLAG(flag_client_read);
32 
read_test(struct bt_conn * conn,const struct bt_gatt_attr * attr,void * buf,uint16_t len,uint16_t offset)33 static ssize_t read_test(struct bt_conn *conn, const struct bt_gatt_attr *attr,
34 			void *buf, uint16_t len, uint16_t offset)
35 {
36 	const char *value = attr->user_data;
37 
38 	printk("Client has read from test char\n");
39 	SET_FLAG(flag_client_read);
40 
41 	return bt_gatt_attr_read(conn, attr, buf, len, offset, value,
42 				 strlen(value));
43 }
44 
wait_for_client_read(void)45 void wait_for_client_read(void)
46 {
47 	WAIT_FOR_FLAG(flag_client_read);
48 }
49 
write_test(struct bt_conn * conn,const struct bt_gatt_attr * attr,const void * buf,uint16_t len,uint16_t offset,uint8_t flags)50 static ssize_t write_test(struct bt_conn *conn, const struct bt_gatt_attr *attr,
51 			 const void *buf, uint16_t len, uint16_t offset,
52 			 uint8_t flags)
53 {
54 	uint8_t *value = attr->user_data;
55 
56 	printk("Client has written to test char\n");
57 
58 	if (offset + len > sizeof(test_value)) {
59 		return BT_GATT_ERR(BT_ATT_ERR_INVALID_OFFSET);
60 	}
61 
62 	memcpy(value + offset, buf, len);
63 
64 	return len;
65 }
66 
67 static struct bt_gatt_attr test_attrs[] = {
68 	/* Vendor Primary Service Declaration */
69 	BT_GATT_PRIMARY_SERVICE(&test_svc_uuid),
70 
71 	BT_GATT_CHARACTERISTIC(&test_chrc_uuid.uuid,
72 			       BT_GATT_CHRC_READ | BT_GATT_CHRC_WRITE,
73 			       BT_GATT_PERM_READ |
74 			       BT_GATT_PERM_WRITE,
75 			       read_test, write_test, test_value),
76 };
77 
78 static struct bt_gatt_attr test_attrs_2[] = {
79 	/* Vendor Primary Service Declaration */
80 	BT_GATT_PRIMARY_SERVICE(&test_svc_uuid_2),
81 
82 	BT_GATT_CHARACTERISTIC(&test_chrc_uuid.uuid,
83 			       BT_GATT_CHRC_READ | BT_GATT_CHRC_WRITE,
84 			       BT_GATT_PERM_READ_ENCRYPT |
85 			       BT_GATT_PERM_WRITE_ENCRYPT,
86 			       read_test, write_test, test_value),
87 };
88 
89 static struct bt_gatt_service test_svc = BT_GATT_SERVICE(test_attrs);
90 static struct bt_gatt_service test_svc_2 = BT_GATT_SERVICE(test_attrs_2);
91 
gatt_register_service_1(void)92 void gatt_register_service_1(void)
93 {
94 	int err = bt_gatt_service_register(&test_svc);
95 
96 	__ASSERT(!err, "Failed to register GATT service (err %d)\n", err);
97 }
98 
gatt_register_service_2(void)99 void gatt_register_service_2(void)
100 {
101 	/* This service is only used to trigger a GATT DB change.
102 	 * No reads or writes will be attempted.
103 	 */
104 	int err = bt_gatt_service_register(&test_svc_2);
105 
106 	__ASSERT(!err, "Failed to register GATT service (err %d)\n", err);
107 }
108 
109 /* We need to discover:
110  * - Dynamic service
111  * - Client Features (to set robust caching)
112  * - Service Changed (to sub to indications)
113  */
114 enum GATT_HANDLES {
115 CLIENT_FEATURES,
116 SERVICE_CHANGED,
117 TEST_CHAR,
118 NUM_HANDLES,
119 };
120 
121 uint16_t gatt_handles[NUM_HANDLES] = {0};
122 
123 DEFINE_FLAG(flag_discovered);
124 
discover_func(struct bt_conn * conn,const struct bt_gatt_attr * attr,struct bt_gatt_discover_params * params)125 static uint8_t discover_func(struct bt_conn *conn, const struct bt_gatt_attr *attr,
126 			     struct bt_gatt_discover_params *params)
127 {
128 	if (attr == NULL) {
129 		for (int i = 0; i < ARRAY_SIZE(gatt_handles); i++) {
130 			printk("handle[%d] = 0x%x\n", i, gatt_handles[i]);
131 
132 			if (gatt_handles[i] == 0) {
133 				FAIL("Did not discover all characteristics\n");
134 			}
135 		}
136 
137 		(void)memset(params, 0, sizeof(*params));
138 
139 		SET_FLAG(flag_discovered);
140 
141 		return BT_GATT_ITER_STOP;
142 	}
143 
144 	if (params->type == BT_GATT_DISCOVER_CHARACTERISTIC) {
145 		const struct bt_gatt_chrc *chrc = (struct bt_gatt_chrc *)attr->user_data;
146 
147 		if (bt_uuid_cmp(chrc->uuid, BT_UUID_GATT_CLIENT_FEATURES) == 0) {
148 			printk("Found client supported features\n");
149 			gatt_handles[CLIENT_FEATURES] = chrc->value_handle;
150 
151 		} else if (bt_uuid_cmp(chrc->uuid, BT_UUID_GATT_SC) == 0) {
152 			printk("Found service changed\n");
153 			gatt_handles[SERVICE_CHANGED] = chrc->value_handle;
154 
155 		} else if (bt_uuid_cmp(chrc->uuid, &test_chrc_uuid.uuid) == 0) {
156 			printk("Found test characteristic\n");
157 			gatt_handles[TEST_CHAR] = chrc->value_handle;
158 		}
159 	}
160 
161 	return BT_GATT_ITER_CONTINUE;
162 }
163 
164 DEFINE_FLAG(flag_sc_indicated);
sc_indicated(struct bt_conn * conn,struct bt_gatt_subscribe_params * params,const void * data,uint16_t length)165 static uint8_t sc_indicated(struct bt_conn *conn,
166 			    struct bt_gatt_subscribe_params *params,
167 			    const void *data, uint16_t length)
168 {
169 	if (!data) {
170 		params->value_handle = 0U;
171 		return BT_GATT_ITER_STOP;
172 	}
173 
174 	printk("SC received\n");
175 	SET_FLAG(flag_sc_indicated);
176 
177 	return BT_GATT_ITER_CONTINUE;
178 }
179 
wait_for_sc_indication(void)180 void wait_for_sc_indication(void)
181 {
182 	WAIT_FOR_FLAG(flag_sc_indicated);
183 }
184 
185 DEFINE_FLAG(flag_sc_subscribed);
sc_subscribed(struct bt_conn * conn,uint8_t err,struct bt_gatt_subscribe_params * params)186 static void sc_subscribed(struct bt_conn *conn, uint8_t err,
187 			  struct bt_gatt_subscribe_params *params)
188 {
189 	if (params->value) {
190 		printk("SC subscribed\n");
191 		SET_FLAG(flag_sc_subscribed);
192 	} else {
193 		printk("SC unsubscribed\n");
194 		UNSET_FLAG(flag_sc_subscribed);
195 	}
196 }
197 
198 static struct bt_gatt_discover_params disc_params;
199 static struct bt_gatt_subscribe_params subscribe_params;
gatt_subscribe_to_service_changed(bool subscribe)200 void gatt_subscribe_to_service_changed(bool subscribe)
201 {
202 	int err;
203 
204 	subscribe_params.value_handle = gatt_handles[SERVICE_CHANGED];
205 	subscribe_params.notify = sc_indicated;
206 	subscribe_params.subscribe = sc_subscribed;
207 
208 	if (subscribe) {
209 		subscribe_params.ccc_handle = BT_GATT_AUTO_DISCOVER_CCC_HANDLE;
210 		subscribe_params.disc_params = &disc_params,
211 		subscribe_params.value = BT_GATT_CCC_INDICATE;
212 		subscribe_params.end_handle = BT_ATT_LAST_ATTRIBUTE_HANDLE;
213 
214 		err = bt_gatt_subscribe(get_conn(), &subscribe_params);
215 		WAIT_FOR_FLAG(flag_sc_subscribed);
216 	} else {
217 		/* Params are already set to the correct values by the previous
218 		 * call of this fn.
219 		 */
220 		err = bt_gatt_unsubscribe(get_conn(), &subscribe_params);
221 		WAIT_FOR_FLAG_UNSET(flag_sc_subscribed);
222 	}
223 
224 	if (err != 0) {
225 		FAIL("Subscription failed(err %d)\n", err);
226 	} else {
227 		printk("%subscribed %s SC indications\n",
228 		       subscribe ? "S" : "Uns",
229 		       subscribe ? "to" : "from");
230 	}
231 }
232 
gatt_discover(void)233 void gatt_discover(void)
234 {
235 	static struct bt_gatt_discover_params discover_params;
236 	int err;
237 
238 	printk("Discovering services and characteristics\n");
239 	UNSET_FLAG(flag_discovered);
240 
241 	discover_params.uuid = NULL;
242 	discover_params.func = discover_func;
243 	discover_params.start_handle = BT_ATT_FIRST_ATTRIBUTE_HANDLE;
244 	discover_params.end_handle = BT_ATT_LAST_ATTRIBUTE_HANDLE;
245 	discover_params.type = BT_GATT_DISCOVER_CHARACTERISTIC;
246 
247 	err = bt_gatt_discover(get_conn(), &discover_params);
248 	if (err != 0) {
249 		FAIL("Discover failed(err %d)\n", err);
250 	}
251 
252 	WAIT_FOR_FLAG(flag_discovered);
253 	printk("Discover complete\n");
254 }
255 
256 DEFINE_FLAG(flag_written);
257 
write_cb(struct bt_conn * conn,uint8_t err,struct bt_gatt_write_params * params)258 static void write_cb(struct bt_conn *conn, uint8_t err, struct bt_gatt_write_params *params)
259 {
260 	if (err != BT_ATT_ERR_SUCCESS) {
261 		FAIL("Write failed: 0x%02X\n", err);
262 	}
263 
264 	SET_FLAG(flag_written);
265 }
266 
267 #define CF_BIT_ROBUST_CACHING 0
activate_robust_caching(void)268 void activate_robust_caching(void)
269 {
270 	int err;
271 
272 	static const uint8_t csf = BIT(CF_BIT_ROBUST_CACHING);
273 	static struct bt_gatt_write_params write_params = {
274 		.func = write_cb,
275 		.offset = 0,
276 		.data = &csf,
277 		.length = sizeof(csf),
278 	};
279 
280 	write_params.handle = gatt_handles[CLIENT_FEATURES];
281 
282 	UNSET_FLAG(flag_written);
283 	err = bt_gatt_write(get_conn(), &write_params);
284 
285 	__ASSERT(!err, "Failed to enable robust caching\n");
286 
287 	WAIT_FOR_FLAG(flag_written);
288 	printk("Robust caching enabled\n");
289 }
290 
291 DEFINE_FLAG(flag_read);
292 
_expect_success(struct bt_conn * conn,uint8_t err,struct bt_gatt_read_params * params,const void * data,uint16_t length)293 static uint8_t _expect_success(struct bt_conn *conn, uint8_t err,
294 			       struct bt_gatt_read_params *params,
295 			       const void *data, uint16_t length)
296 {
297 	/* printk("GATT read cb: err 0x%02X\n", err); */
298 	__ASSERT(err == 0, "Failed to read: err 0x%x\n", err);
299 
300 	SET_FLAG(flag_read);
301 
302 	return 0;
303 }
304 
_expect_out_of_sync_cb(struct bt_conn * conn,uint8_t err,struct bt_gatt_read_params * params,const void * data,uint16_t length)305 static uint8_t _expect_out_of_sync_cb(struct bt_conn *conn, uint8_t err,
306 				     struct bt_gatt_read_params *params,
307 				     const void *data, uint16_t length)
308 {
309 	/* printk("GATT read cb: err 0x%02X\n", err); */
310 	__ASSERT(err == BT_ATT_ERR_DB_OUT_OF_SYNC,
311 		 "Didn't get expected error code: err 0x%x\n", err);
312 
313 	SET_FLAG(flag_read);
314 
315 	return 0;
316 }
317 
read_char(uint16_t handle,bool expect_success)318 static void read_char(uint16_t handle, bool expect_success)
319 {
320 	int err;
321 
322 	struct bt_gatt_read_params read_params = {
323 		.handle_count = 1,
324 		.single = {
325 			.handle = handle,
326 			.offset = 0,
327 		},
328 	};
329 
330 	if (expect_success) {
331 		read_params.func = _expect_success;
332 	} else {
333 		read_params.func = _expect_out_of_sync_cb;
334 	}
335 
336 	UNSET_FLAG(flag_read);
337 
338 	err = bt_gatt_read(get_conn(), &read_params);
339 	__ASSERT(!err, "Failed to read char\n");
340 
341 	WAIT_FOR_FLAG(flag_read);
342 }
343 
read_test_char(bool expect_success)344 void read_test_char(bool expect_success)
345 {
346 	read_char(gatt_handles[TEST_CHAR], expect_success);
347 }
348 
gatt_clear_flags(void)349 void gatt_clear_flags(void)
350 {
351 	UNSET_FLAG(flag_client_read);
352 	UNSET_FLAG(flag_discovered);
353 	UNSET_FLAG(flag_sc_indicated);
354 	UNSET_FLAG(flag_sc_subscribed);
355 	UNSET_FLAG(flag_written);
356 	UNSET_FLAG(flag_read);
357 }
358