xref: /btstack/src/ble/att_db.h (revision d58a1b5f11ada8ddf896c41fff5a35e7f140c37e)
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 
39 #ifndef ATT_DB_H
40 #define ATT_DB_H
41 
42 #include <stdint.h>
43 #include "bluetooth.h"
44 #include "btstack_linked_list.h"
45 #include "btstack_defines.h"
46 
47 #if defined __cplusplus
48 extern "C" {
49 #endif
50 
51 // MARK: Attribute PDU Opcodes
52 #define ATT_ERROR_RESPONSE              0x01
53 
54 #define ATT_EXCHANGE_MTU_REQUEST        0x02
55 #define ATT_EXCHANGE_MTU_RESPONSE       0x03
56 
57 #define ATT_FIND_INFORMATION_REQUEST    0x04
58 #define ATT_FIND_INFORMATION_REPLY      0x05
59 #define ATT_FIND_BY_TYPE_VALUE_REQUEST  0x06
60 #define ATT_FIND_BY_TYPE_VALUE_RESPONSE 0x07
61 
62 #define ATT_READ_BY_TYPE_REQUEST        0x08
63 #define ATT_READ_BY_TYPE_RESPONSE       0x09
64 #define ATT_READ_REQUEST                0x0a
65 #define ATT_READ_RESPONSE               0x0b
66 #define ATT_READ_BLOB_REQUEST           0x0c
67 #define ATT_READ_BLOB_RESPONSE          0x0d
68 #define ATT_READ_MULTIPLE_REQUEST       0x0e
69 #define ATT_READ_MULTIPLE_RESPONSE      0x0f
70 #define ATT_READ_BY_GROUP_TYPE_REQUEST  0x10
71 #define ATT_READ_BY_GROUP_TYPE_RESPONSE 0x11
72 
73 #define ATT_WRITE_REQUEST               0x12
74 #define ATT_WRITE_RESPONSE              0x13
75 
76 #define ATT_PREPARE_WRITE_REQUEST       0x16
77 #define ATT_PREPARE_WRITE_RESPONSE      0x17
78 #define ATT_EXECUTE_WRITE_REQUEST       0x18
79 #define ATT_EXECUTE_WRITE_RESPONSE      0x19
80 
81 #define ATT_HANDLE_VALUE_NOTIFICATION   0x1b
82 #define ATT_HANDLE_VALUE_INDICATION     0x1d
83 #define ATT_HANDLE_VALUE_CONFIRMATION   0x1e
84 
85 
86 #define ATT_WRITE_COMMAND                0x52
87 #define ATT_SIGNED_WRITE_COMMAND         0xD2
88 
89 // custom BTstack ATT Response Pending for att_read_callback
90 #define ATT_READ_RESPONSE_PENDING                 0xffff
91 
92 // internally used to signal write response pending
93 #define ATT_INTERNAL_WRITE_RESPONSE_PENDING       0xfffe
94 
95 // internal additions
96 // 128 bit UUID used
97 #define ATT_PROPERTY_UUID128             0x200
98 // Read/Write Permission bits
99 #define ATT_PROPERTY_READ_PERMISSION_BIT_0  0x0400
100 #define ATT_PROPERTY_READ_PERMISSION_BIT_1  0x0800
101 #define ATT_PROPERTY_WRITE_PERMISSION_BIT_0 0x0001
102 #define ATT_PROPERTY_WRITE_PERMISSION_BIT_1 0x0010
103 #define ATT_PROPERTY_READ_PERMISSION_SC     0x0020
104 #define ATT_PROPERTY_WRITE_PERMISSION_SC    0x0080
105 
106 
107 typedef struct att_connection {
108     hci_con_handle_t con_handle;
109     uint16_t mtu;       // initialized to ATT_DEFAULT_MTU (23), negotiated during MTU exchange
110     uint16_t max_mtu;   // local maximal L2CAP_MTU, set to l2cap_max_le_mtu()
111     uint8_t  encryption_key_size;
112     uint8_t  authenticated;
113     uint8_t  authorized;
114     uint8_t  secure_connection;
115 } att_connection_t;
116 
117 // ATT Client Read Callback for Dynamic Data
118 // - if buffer == NULL, don't copy data, just return size of value
119 // - if buffer != NULL, copy data and return number bytes copied
120 // If ENABLE_ATT_DELAYED_READ_RESPONSE is defined, you may return ATT_READ_RESPONSE_PENDING if data isn't available yet
121 // @param con_handle of hci le connection
122 // @param attribute_handle to be read
123 // @param offset defines start of attribute value
124 // @param buffer
125 // @param buffer_size
126 typedef uint16_t (*att_read_callback_t)(hci_con_handle_t con_handle, uint16_t attribute_handle, uint16_t offset, uint8_t * buffer, uint16_t buffer_size);
127 
128 // ATT Client Write Callback for Dynamic Data
129 // @param con_handle of hci le connection
130 // @param attribute_handle to be written
131 // @param transaction - ATT_TRANSACTION_MODE_NONE for regular writes. For prepared writes: ATT_TRANSACTION_MODE_ACTIVE, ATT_TRANSACTION_MODE_VALIDATE, ATT_TRANSACTION_MODE_EXECUTE, ATT_TRANSACTION_MODE_CANCEL
132 // @param offset into the value - used for queued writes and long attributes
133 // @param buffer
134 // @param buffer_size
135 // @param signature used for signed write commmands
136 // @returns 0 if write was ok, ATT_ERROR_PREPARE_QUEUE_FULL if no space in queue, ATT_ERROR_INVALID_OFFSET if offset is larger than max buffer
137 //
138 // Each Prepared Write Request triggers a callback with transaction mode ATT_TRANSACTION_MODE_ACTIVE.
139 // On Execute Write, the callback will be called with ATT_TRANSACTION_MODE_VALIDATE and allows to validate all queued writes and return an application error.
140 // If none of the registered callbacks return an error for ATT_TRANSACTION_MODE_VALIDATE and the callback will be called with ATT_TRANSACTION_MODE_EXECUTE.
141 // Otherwise, all callbacks will be called with ATT_TRANSACTION_MODE_CANCEL.
142 //
143 // If the additional validation step is not needed, just return 0 for all callbacks with transaction mode ATT_TRANSACTION_MODE_VALIDATE.
144 //
145 typedef int (*att_write_callback_t)(hci_con_handle_t con_handle, uint16_t attribute_handle, uint16_t transaction_mode, uint16_t offset, uint8_t *buffer, uint16_t buffer_size);
146 
147 // Read & Write Callbacks for handle range
148 typedef struct att_service_handler {
149     btstack_linked_item_t * item;
150     uint16_t start_handle;
151     uint16_t end_handle;
152     att_read_callback_t read_callback;
153     att_write_callback_t write_callback;
154     btstack_packet_handler_t packet_handler;
155 } att_service_handler_t;
156 
157 // MARK: ATT Operations
158 
159 /*
160  * @brief setup ATT database
161  */
162 void att_set_db(uint8_t const * db);
163 
164 /*
165  * @brief set callback for read of dynamic attributes
166  * @param callback
167  */
168 void att_set_read_callback(att_read_callback_t callback);
169 
170 /*
171  * @brief set callback for write of dynamic attributes
172  * @param callback
173  */
174 void att_set_write_callback(att_write_callback_t callback);
175 
176 /*
177  * @brief debug helper, dump ATT database to stdout using log_info
178  */
179 void att_dump_attributes(void);
180 
181 /*
182  * @brief process ATT request against database and put response into response buffer
183  * @param att_connection used for mtu and security properties
184  * @param request_buffer, request_len: ATT request from clinet
185  * @param response_buffer for result
186  * @returns len of data in response buffer. 0 = no response,
187  *          ATT_READ_RESPONSE_PENDING if it was returned at least once for dynamic data (requires ENABLE_ATT_DELAYED_READ_RESPONSE)
188  */
189 uint16_t att_handle_request(att_connection_t * att_connection,
190                             uint8_t * request_buffer,
191                             uint16_t request_len,
192                             uint8_t * response_buffer);
193 
194 /*
195  * @brief setup value notification in response buffer for a given handle and value
196  * @param att_connection
197  * @param attribute_handle
198  * @param value
199  * @param value_len
200  * @param response_buffer for notification
201  */
202 uint16_t att_prepare_handle_value_notification(att_connection_t * att_connection,
203                                                uint16_t attribute_handle,
204                                                const uint8_t *value,
205                                                uint16_t value_len,
206                                                uint8_t * response_buffer);
207 
208 /*
209  * @brief setup value indication in response buffer for a given handle and value
210  * @param att_connection
211  * @param attribute_handle
212  * @param value
213  * @param value_len
214  * @param response_buffer for indication
215  */
216 uint16_t att_prepare_handle_value_indication(att_connection_t * att_connection,
217                                              uint16_t attribute_handle,
218                                              const uint8_t *value,
219                                              uint16_t value_len,
220                                              uint8_t * response_buffer);
221 
222 /*
223  * @brief transcation queue of prepared writes, e.g., after disconnect
224  */
225 void att_clear_transaction_queue(att_connection_t * att_connection);
226 
227 // att_read_callback helpers for a various data types
228 
229 /*
230  * @brief Handle read of blob like data for att_read_callback
231  * @param blob of data
232  * @param blob_size of blob
233  * @param offset from att_read_callback
234  * @param buffer from att_read_callback
235  * @param buffer_size from att_read_callback
236  * @returns value size for buffer == 0 and num bytes copied otherwise
237  */
238 uint16_t att_read_callback_handle_blob(const uint8_t * blob, uint16_t blob_size, uint16_t offset, uint8_t * buffer, uint16_t buffer_size);
239 
240 /*
241  * @brief Handle read of little endian unsigned 32 bit value for att_read_callback
242  * @param value
243  * @param offset from att_read_callback
244  * @param buffer from att_read_callback
245  * @param buffer_size from att_read_callback
246  * @returns value size for buffer == 0 and num bytes copied otherwise
247  */
248 uint16_t att_read_callback_handle_little_endian_32(uint32_t value, uint16_t offset, uint8_t * buffer, uint16_t buffer_size);
249 
250 /*
251  * @brief Handle read of little endian unsigned 16 bit value for att_read_callback
252  * @param value
253  * @param offset from att_read_callback
254  * @param buffer from att_read_callback
255  * @param buffer_size from att_read_callback
256  * @returns value size for buffer == 0 and num bytes copied otherwise
257  */
258 uint16_t att_read_callback_handle_little_endian_16(uint16_t value, uint16_t offset, uint8_t * buffer, uint16_t buffer_size);
259 
260 /*
261  * @brief Handle read of single byte for att_read_callback
262  * @param blob of data
263  * @param blob_size of blob
264  * @param offset from att_read_callback
265  * @param buffer from att_read_callback
266  * @param buffer_size from att_read_callback
267  * @returns value size for buffer == 0 and num bytes copied otherwise
268  */
269 uint16_t att_read_callback_handle_byte(uint8_t value, uint16_t offset, uint8_t * buffer, uint16_t buffer_size);
270 
271 
272 // experimental client API
273 uint16_t att_uuid_for_handle(uint16_t attribute_handle);
274 
275 
276 // experimental GATT Server API
277 
278 // returns 1 if service found. only primary service.
279 int gatt_server_get_get_handle_range_for_service_with_uuid16(uint16_t uuid16, uint16_t * start_handle, uint16_t * end_handle);
280 
281 // returns 0 if not found
282 uint16_t gatt_server_get_value_handle_for_characteristic_with_uuid16(uint16_t start_handle, uint16_t end_handle, uint16_t uuid16);
283 
284 // returns 0 if not found
285 uint16_t gatt_server_get_descriptor_handle_for_characteristic_with_uuid16(uint16_t start_handle, uint16_t end_handle, uint16_t characteristic_uuid16, uint16_t descriptor_uuid16);
286 uint16_t gatt_server_get_client_configuration_handle_for_characteristic_with_uuid16(uint16_t start_handle, uint16_t end_handle, uint16_t characteristic_uuid16);
287 uint16_t gatt_server_get_server_configuration_handle_for_characteristic_with_uuid16(uint16_t start_handle, uint16_t end_handle, uint16_t characteristic_uuid16);
288 
289 
290 // returns 1 if service found. only primary service.
291 int gatt_server_get_get_handle_range_for_service_with_uuid128(const uint8_t * uuid128, uint16_t * start_handle, uint16_t * end_handle);
292 
293 // returns 0 if not found
294 uint16_t gatt_server_get_value_handle_for_characteristic_with_uuid128(uint16_t start_handle, uint16_t end_handle, const uint8_t * uuid128);
295 
296 // returns 0 if not found
297 uint16_t gatt_server_get_client_configuration_handle_for_characteristic_with_uuid128(uint16_t start_handle, uint16_t end_handle, const uint8_t * uuid128);
298 
299 // non-user functionality for att_server
300 
301 /*
302  * @brief Check if writes to handle should be persistent
303  * @param handle
304  * @returns 1 if persistent
305  */
306 int att_is_persistent_ccc(uint16_t handle);
307 
308 
309 #if defined __cplusplus
310 }
311 #endif
312 
313 #endif // ATT_H
314